Sample records for joysticks computers

  1. The nature of arm movement in children with cerebral palsy when using computer-generated exercise games.

    PubMed

    Weightman, Andrew; Preston, Nick; Levesley, Martin; Bhakta, Bipin; Holt, Raymond; Mon-Williams, Mark

    2014-05-01

    To compare upper limb kinematics of children with spastic cerebral palsy (CP) using a passive rehabilitation joystick with those of adults and able-bodied children, to better understand the design requirements of computer-based rehabilitation devices. A blocked comparative study involving seven children with spastic CP, nine able-bodied adults and nine able-bodied children, using a joystick system to play a computer game whilst the kinematics of their upper limb were recorded. The translational kinematics of the joystick's end point and the participant's shoulder movement (protraction/retraction) and elbow rotational kinematics (flexion/extension) were analysed for each group. Children with spastic CP matched their able-bodied peers in the time taken to complete the computer task, but this was due to a failure to adhere to the task instructions of travelling along a prescribed straight line when moving between targets. The spastic CP group took longer to initiate the first movement, which showed jerkier trajectories and demonstrated qualitatively different movement patterns when using the joystick, with shoulder movements that were significantly of greater magnitude than the able-bodied participants. Children with spastic CP generate large shoulder and hence trunk movements when using a joystick to undertake computer-generated arm exercises. This finding has implications for the development and use of assistive technologies to encourage exercise and the instructions given to users of such systems. A kinematic analysis of upper limb function of children with CP when using joystick devices is presented. Children with CP may use upper body movements to compensate for limitations in voluntary shoulder and elbow movements when undertaking computer games designed to encourage the practice of arm movement. The design of rehabilitative computer exercise systems should consider movement of the torso/shoulder as it may have implications for the quality of therapy in the rehabilitation of the upper limb in children with CP.

  2. Generating Control Commands From Gestures Sensed by EMG

    NASA Technical Reports Server (NTRS)

    Wheeler, Kevin R.; Jorgensen, Charles

    2006-01-01

    An effort is under way to develop noninvasive neuro-electric interfaces through which human operators could control systems as diverse as simple mechanical devices, computers, aircraft, and even spacecraft. The basic idea is to use electrodes on the surface of the skin to acquire electromyographic (EMG) signals associated with gestures, digitize and process the EMG signals to recognize the gestures, and generate digital commands to perform the actions signified by the gestures. In an experimental prototype of such an interface, the EMG signals associated with hand gestures are acquired by use of several pairs of electrodes mounted in sleeves on a subject s forearm (see figure). The EMG signals are sampled and digitized. The resulting time-series data are fed as input to pattern-recognition software that has been trained to distinguish gestures from a given gesture set. The software implements, among other things, hidden Markov models, which are used to recognize the gestures as they are being performed in real time. Thus far, two experiments have been performed on the prototype interface to demonstrate feasibility: an experiment in synthesizing the output of a joystick and an experiment in synthesizing the output of a computer or typewriter keyboard. In the joystick experiment, the EMG signals were processed into joystick commands for a realistic flight simulator for an airplane. The acting pilot reached out into the air, grabbed an imaginary joystick, and pretended to manipulate the joystick to achieve left and right banks and up and down pitches of the simulated airplane. In the keyboard experiment, the subject pretended to type on a numerical keypad, and the EMG signals were processed into keystrokes. The results of the experiments demonstrate the basic feasibility of this method while indicating the need for further research to reduce the incidence of errors (including confusion among gestures). Topics that must be addressed include the numbers and arrangements of electrodes needed to acquire sufficient data; refinements in the acquisition, filtering, and digitization of EMG signals; and methods of training the pattern- recognition software. The joystick and keyboard simulations were chosen for the initial experiments because they are familiar to many computer users. It is anticipated that, ultimately, interfaces would utilize EMG signals associated with movements more nearly natural than those associated with joysticks or keyboards. Future versions of the pattern-recognition software are planned to be capable of adapting to the preferences and day-today variations in EMG outputs of individual users; this capability for adaptation would also make it possible to select gestures that, to a given user, feel the most nearly natural for generating control signals for a given task (provided that there are enough properly positioned electrodes to acquire the EMG signals from the muscles involved in the gestures).

  3. Design and Application of a Novel Virtual Reality Navigational Technology (VRNChair).

    PubMed

    Byagowi, Ahmad; Mohaddes, Danyal; Moussavi, Zahra

    2014-01-01

    This paper presents a novel virtual reality navigation (VRN) input device, called the VRNChair, offering an intuitive and natural way to interact with virtual reality (VR) environments. Traditionally, VR navigation tests are performed using stationary input devices such as keyboards or joysticks. However, in case of immersive VR environment experiments, such as our recent VRN assessment, the user may feel kinetosis (motion sickness) as a result of the disagreement between vestibular response and the optical flow. In addition, experience in using a joystick or any of the existing computer input devices may cause a bias in the accuracy of participant performance in VR environment experiments. Therefore, we have designed a VR navigational environment that is operated using a wheelchair (VRNChair). The VRNChair translates the movement of a manual wheelchair to feed any VR environment. We evaluated the VRNChair by testing on 34 young individuals in two groups performing the same navigational task with either the VRNChair or a joystick; also one older individual (55 years) performed the same experiment with both a joystick and the VRNChair. The results indicate that the VRNChair does not change the accuracy of the performance; thus removing the plausible bias of having experience using a joystick. More importantly, it significantly reduces the effect of kinetosis. While we developed VRNChair for our spatial cognition study, its application can be in many other studies involving neuroscience, neurorehabilitation, physiotherapy, and/or simply the gaming industry.

  4. 3D joystick for robotic arm control by individuals with high level spinal cord injuries.

    PubMed

    Jiang, Hairong; Wachs, Juan P; Pendergast, Martin; Duerstock, Bradley S

    2013-06-01

    An innovative 3D joystick was developed to enable quadriplegics due to spinal cord injuries (SCIs) to more independently and efficiently operate a robotic arm as an assistive device. The 3D joystick was compared to two different manual input modalities, a keyboard control and a traditional joystick, in performing experimental robotic arm tasks by both subjects without disabilities and those with upper extremity mobility impairments. Fitts's Law targeting and practical pouring tests were conducted to compare the performance and accuracy of the proposed 3D joystick. The Fitts's law measurements showed that the 3D joystick had the best index of performance (IP), though it required an equivalent number of operations and errors as the standard robotic arm joystick. The pouring task demonstrated that the 3D joystick took significantly less task completion time and was more accurate than keyboard control. The 3D joystick also showed a decreased learning curve to the other modalities.

  5. Increasing patient engagement in rehabilitation exercises using computer-based citizen science.

    PubMed

    Laut, Jeffrey; Cappa, Francesco; Nov, Oded; Porfiri, Maurizio

    2015-01-01

    Patient motivation is an important factor to consider when developing rehabilitation programs. Here, we explore the effectiveness of active participation in web-based citizen science activities as a means of increasing participant engagement in rehabilitation exercises, through the use of a low-cost haptic joystick interfaced with a laptop computer. Using the joystick, patients navigate a virtual environment representing the site of a citizen science project situated in a polluted canal. Participants are tasked with following a path on a laptop screen representing the canal. The experiment consists of two conditions: in one condition, a citizen science component where participants classify images from the canal is included; and in the other, the citizen science component is absent. Both conditions are tested on a group of young patients undergoing rehabilitation treatments and a group of healthy subjects. A survey administered at the end of both tasks reveals that participants prefer performing the scientific task, and are more likely to choose to repeat it, even at the cost of increasing the time of their rehabilitation exercise. Furthermore, performance indices based on data collected from the joystick indicate significant differences in the trajectories created by patients and healthy subjects, suggesting that the low-cost device can be used in a rehabilitation setting for gauging patient recovery.

  6. Direct surgeon control of the computer in the operating room.

    PubMed

    Onceanu, Dumitru; Stewart, A James

    2011-01-01

    This paper describes the design and evaluation of a joystick-like device that allows direct surgeon control of the computer in the operating room. The device contains no electronic parts, is easy to use, is unobtrusive, has no physical connection to the computer, and makes use of an existing surgical tool. The device was tested in comparison to a mouse and to verbal dictation.

  7. Ocular attention-sensing interface system

    NASA Technical Reports Server (NTRS)

    Zaklad, Allen; Glenn, Floyd A., III; Iavecchia, Helene P.; Stokes, James M.

    1986-01-01

    The purpose of the research was to develop an innovative human-computer interface based on eye movement and voice control. By eliminating a manual interface (keyboard, joystick, etc.), OASIS provides a control mechanism that is natural, efficient, accurate, and low in workload.

  8. Force Feedback Joystick

    NASA Technical Reports Server (NTRS)

    1997-01-01

    I-FORCE, a computer peripheral from Immersion Corporation, was derived from virtual environment and human factors research at the Advanced Displays and Spatial Perception Laboratory at Ames Research Center in collaboration with Stanford University Center for Design Research. Entrepreneur Louis Rosenberg, a former Stanford researcher, now president of Immersion, collaborated with Dr. Bernard Adelstein at Ames on studies of perception in virtual reality. The result was an inexpensive way to incorporate motors and a sophisticated microprocessor into joysticks and other game controllers. These devices can emulate the feel of a car on the skid, a crashing plane, the bounce of a ball, compressed springs, or other physical phenomenon. The first products incorporating I-FORCE technology include CH- Products' line of FlightStick and CombatStick controllers.

  9. Effects of directional uncertainty on visually-guided joystick pointing.

    PubMed

    Berryhill, Marian; Kveraga, Kestutis; Hughes, Howard C

    2005-02-01

    Reaction times generally follow the predictions of Hick's law as stimulus-response uncertainty increases, although notable exceptions include the oculomotor system. Saccadic and smooth pursuit eye movement reaction times are independent of stimulus-response uncertainty. Previous research showed that joystick pointing to targets, a motor analog of saccadic eye movements, is only modestly affected by increased stimulus-response uncertainty; however, a no-uncertainty condition (simple reaction time to 1 possible target) was not included. Here, we re-evaluate manual joystick pointing including a no-uncertainty condition. Analysis indicated simple joystick pointing reaction times were significantly faster than choice reaction times. Choice reaction times (2, 4, or 8 possible target locations) only slightly increased as the number of possible targets increased. These data suggest that, as with joystick tracking (a motor analog of smooth pursuit eye movements), joystick pointing is more closely approximated by a simple/choice step function than the log function predicted by Hick's law.

  10. Improving Control of Two Motor Controllers

    NASA Technical Reports Server (NTRS)

    Toland, Ronald W.

    2004-01-01

    A computer program controls motors that drive translation stages in a metrology system that consists of a pair of two-axis cathetometers. This program is specific to Compumotor Gemini (or equivalent) motors and the Compumotor 6K-series (or equivalent) motor controller. Relative to the software supplied with the controller, this program affords more capabilities and is easier to use. Written as a Virtual Instrument in the LabVIEW software system, the program presents an imitation control panel that the user can manipulate by use of a keyboard and mouse. There are three modes of operation: command, movement, and joystick. In command mode, single commands are sent to the controller for troubleshooting. In movement mode, distance, speed, and/or acceleration commands are sent to the controller. Position readouts from the motors and from position encoders on the translation stages are displayed in marked fields. At any time, the position readouts can be recorded in a file named by the user. In joystick mode, the program yields control of the motors to a joystick. The program sends commands to, and receives data from, the controller via a serial cable connection, using the serial-communication portion of the software supplied with the controller.

  11. Assessment of Joystick control during the performance of powered wheelchair driving tasks

    PubMed Central

    2011-01-01

    Background Powered wheelchairs are essential for many individuals who have mobility impairments. Nevertheless, if operated improperly, the powered wheelchair poses dangers to both the user and to those in its vicinity. Thus, operating a powered wheelchair with some degree of proficiency is important for safety, and measuring driving skills becomes an important issue to address. The objective of this study was to explore the discriminate validity of outcome measures of driving skills based on joystick control strategies and performance recorded using a data logging system. Methods We compared joystick control strategies and performance during standardized driving tasks between a group of 10 expert and 13 novice powered wheelchair users. Driving tasks were drawn from the Wheelchair Skills Test (v. 4.1). Data from the joystick controller were collected on a data logging system. Joystick control strategies and performance outcome measures included the mean number of joystick movements, time required to complete tasks, as well as variability of joystick direction. Results In simpler tasks, the expert group's driving skills were comparable to those of the novice group. Yet, in more difficult and spatially confined tasks, the expert group required fewer joystick movements for task completion. In some cases, experts also completed tasks in approximately half the time with respect to the novice group. Conclusions The analysis of joystick control made it possible to discriminate between novice and expert powered wheelchair users in a variety of driving tasks. These results imply that in spatially confined areas, a greater powered wheelchair driving skill level is required to complete tasks efficiently. Based on these findings, it would appear that the use of joystick signal analysis constitutes an objective tool for the measurement of powered wheelchair driving skills. This tool may be useful for the clinical assessment and training of powered wheelchair skills. PMID:21609435

  12. Fault tolerant attitude sensing and force feedback control for unmanned aerial vehicles

    NASA Astrophysics Data System (ADS)

    Jagadish, Chirag

    Two aspects of an unmanned aerial vehicle are studied in this work. One is fault tolerant attitude determination and the other is to provide force feedback to the joy-stick of the UAV so as to prevent faulty inputs from the pilot. Determination of attitude plays an important role in control of aerial vehicles. One way of defining the attitude is through Euler angles. These angles can be determined based on the measurements of the projections of the gravity and earth magnetic fields on the three body axes of the vehicle. Attitude determination in unmanned aerial vehicles poses additional challenges due to limitations of space, payload, power and cost. Therefore it provides for almost no room for any bulky sensors or extra sensor hardware for backup and as such leaves no room for sensor fault issues either. In the face of these limitations, this study proposes a fault tolerant computing of Euler angles by utilizing multiple different computation methods, with each method utilizing a different subset of the available sensor measurement data. Twenty-five such methods have been presented in this document. The capability of computing the Euler angles in multiple ways provides a diversified redundancy required for fault tolerance. The proposed approach can identify certain sets of sensor failures and even separate the reference fields from the disturbances. A bank-to-turn maneuver of the NASA GTM UAV is used to demonstrate the fault tolerance provided by the proposed method as well as to demonstrate the method of determining the correct Euler angles despite interferences by inertial acceleration disturbances. Attitude computation is essential for stability. But as of today most UAVs are commanded remotely by human pilots. While basic stability control is entrusted to machine or the on-board automatic controller, overall guidance is usually with humans. It is therefore the pilot who sets the command/references through a joy-stick. While this is a good compromise between complete automation and complete human control, it still poses some unique challenges. Pilots of manned aircraft are present inside the cockpit of the aircraft they fly and thus have a better feel of the flying environment and also the limitations of the flight. The same might not be true for UAV pilots stationed on the ground. A major handicap is that visual feedback is the only one available for the UAV pilot. An additional parameter like force feedback on the remote control joy-stick can help the UAV pilot to physically feel the limitation of the safe flight envelope. This can make the flying itself easier and safer. A method proposed here is to design a joy-stick assembly with an additional actuator. This actuator is controlled so as to generate a force feedback on the joy-stick. The control developed for this system is such that the actuator allows free movement for the pilot as long as the UAV is within the safe flight envelope. On the other hand, if it is outside this safe range, the actuator opposes the pilot's applied torque and prevents him/her from giving erroneous commands to the UAV.

  13. Learning Dynamic Control of Body Roll Orientation

    PubMed Central

    Vimal, Vivekanand Pandey; Lackner, James R.; DiZio, Paul

    2016-01-01

    Our objective was to examine how the control of orientation is learned in a task involving dynamically balancing about an unstable equilibrium point, the gravitational vertical, in the absence of leg reflexes and muscle stiffness. Subjects (n=10) used a joystick to set themselves to the gravitational vertical while seated in a multi-axis rotation system device (MARS) programmed with inverted pendulum dynamics. The MARS is driven by powerful servomotors and can faithfully follow joystick commands up to 2.5 Hz with a 30 ms latency. To make the task extremely difficult, the pendulum constant was set to 600°/sec2. Each subject participated in 5 blocks of 4 trials, with a trial ending after a cumulative 100 s of balancing, excluding reset times when a subject lost control. To characterize performance and learning, we used metrics derived from joystick movements, phase portraits (joystick deflections vs MARS position and MARS velocity vs angular position), and stabilogram diffusion functions. We found that as subjects improved their balancing performance they did so by making fewer destabilizing joystick movements and reducing the number and duration of joystick commands. The control strategy they acquired involved making more persistent short-term joystick movements, waiting longer before making changes to ongoing motion, and only intervening intermittently. PMID:26525709

  14. Augmented Reality Imaging System: 3D Viewing of a Breast Cancer.

    PubMed

    Douglas, David B; Boone, John M; Petricoin, Emanuel; Liotta, Lance; Wilson, Eugene

    2016-01-01

    To display images of breast cancer from a dedicated breast CT using Depth 3-Dimensional (D3D) augmented reality. A case of breast cancer imaged using contrast-enhanced breast CT (Computed Tomography) was viewed with the augmented reality imaging, which uses a head display unit (HDU) and joystick control interface. The augmented reality system demonstrated 3D viewing of the breast mass with head position tracking, stereoscopic depth perception, focal point convergence and the use of a 3D cursor and joy-stick enabled fly through with visualization of the spiculations extending from the breast cancer. The augmented reality system provided 3D visualization of the breast cancer with depth perception and visualization of the mass's spiculations. The augmented reality system should be further researched to determine the utility in clinical practice.

  15. Cost effective patient location monitoring system using webcams.

    PubMed

    Logeswaran, Rajasvaran

    2009-10-01

    This paper details the development of a simple webcam joystick, a wireless, or rather cableless, and contactless pointing device by using a webcam and a simple flexible non-electronic joystick. Such a system requires no power source on the joystick, allows for light, robust and very mobile joysticks, and can be extended into a large array of applications. This paper proposes the use of small webcam joysticks as sensors for recording movement, the way wireless sensors are used. Specifically, it could be used as a simple navigation and monitoring system for patient movement in medical wards, where knowledge of patient location and movement could provide instant assistance, pre-emptive action and also hinder untoward patient mix-ups. Experiments and discussions in this paper highlight how a successful implementation is possible, and emphasize the flexibility of such an implementation in a low cost medical environment.

  16. D3D augmented reality imaging system: proof of concept in mammography.

    PubMed

    Douglas, David B; Petricoin, Emanuel F; Liotta, Lance; Wilson, Eugene

    2016-01-01

    The purpose of this article is to present images from simulated breast microcalcifications and assess the pattern of the microcalcifications with a technical development called "depth 3-dimensional (D3D) augmented reality". A computer, head display unit, joystick, D3D augmented reality software, and an in-house script of simulated data of breast microcalcifications in a ductal distribution were used. No patient data was used and no statistical analysis was performed. The D3D augmented reality system demonstrated stereoscopic depth perception by presenting a unique image to each eye, focal point convergence, head position tracking, 3D cursor, and joystick fly-through. The D3D augmented reality imaging system offers image viewing with depth perception and focal point convergence. The D3D augmented reality system should be tested to determine its utility in clinical practice.

  17. Rhesus monkeys (Macaca mulatta), video tasks, and implications for stimulus-response spatial contiguity

    NASA Technical Reports Server (NTRS)

    Rumbaugh, Duane M.; Richardson, W. Kirk; Washburn, David A.; Hopkins, William D.; Savage-Rumbaugh, E. Sue

    1989-01-01

    Recent reports support the argument that the efficiency of primate learning is compromised to the degree that there is spatial discontiguity between discriminands and the locus of response. Experiments are reported here in which two rhesus monkeys easily mastered precise control of a joystick to respond to a variety of computer-generated targets despite the fact that the joystick was located 9 to 18 cm from the video screen. It is argued that stimulus-response contiguity is a significant parameter of learning only to the degree that the monkey visually attends to the directional movements of its hand in order to displace discriminands. If attention is focused on the effects of the hand's movement rather than on the hand itself, stimulus-response contiguity is no longer a primary parameter of learning. The implications of these results for mirror-guided studies are discussed.

  18. Development of a New Intelligent Joystick for People with Reduced Mobility.

    PubMed

    Mrabet, Makrem; Rabhi, Yassine; Fnaiech, Farhat

    2018-01-01

    Despite the diversity of electric wheelchairs, many people with physical limitations and seniors have difficulty using their standard joystick. As a result, they cannot meet their needs or ensure safe travel. Recent assistive technologies can help to give them autonomy and independence. This work deals with the real-time implementation of an artificial intelligence device to overcome these problems. Following a review of the literature from previous work, we present the methodology and process for implementing our intelligent control system on an electric wheelchair. The system is based on a neural algorithm that overcomes problems with standard joystick maneuvers such as the inability to move correctly in one direction. However, this implies the need for an appropriate methodology to map the position of the joystick handle. Experiments on a real wheelchair are carried out with real patients of the Mohamed Kassab National Institute Orthopedic, Physical and Functional Rehabilitation Hospital of Tunis. The proposed intelligent system gives good results compared to the use of a standard joystick.

  19. Development of a New Intelligent Joystick for People with Reduced Mobility

    PubMed Central

    Mrabet, Makrem; Fnaiech, Farhat

    2018-01-01

    Despite the diversity of electric wheelchairs, many people with physical limitations and seniors have difficulty using their standard joystick. As a result, they cannot meet their needs or ensure safe travel. Recent assistive technologies can help to give them autonomy and independence. This work deals with the real-time implementation of an artificial intelligence device to overcome these problems. Following a review of the literature from previous work, we present the methodology and process for implementing our intelligent control system on an electric wheelchair. The system is based on a neural algorithm that overcomes problems with standard joystick maneuvers such as the inability to move correctly in one direction. However, this implies the need for an appropriate methodology to map the position of the joystick handle. Experiments on a real wheelchair are carried out with real patients of the Mohamed Kassab National Institute Orthopedic, Physical and Functional Rehabilitation Hospital of Tunis. The proposed intelligent system gives good results compared to the use of a standard joystick. PMID:29765462

  20. Training Toddlers Seated on Mobile Robots to Steer Using Force-Feedback Joystick.

    PubMed

    Agrawal, S K; Xi Chen; Ragonesi, C; Galloway, J C

    2012-01-01

    The broader goal of our research is to train infants with special needs to safely and purposefully drive a mobile robot to explore the environment. The hypothesis is that these impaired infants will benefit from mobility in their early years and attain childhood milestones, similar to their healthy peers. In this paper, we present an algorithm and training method using a force-feedback joystick with an "assist-as-needed" paradigm for driving training. In this "assist-as-needed" approach, if the child steers the joystick outside a force tunnel centered on the desired direction, the driver experiences a bias force on the hand. We show results with a group study on typically developing toddlers that such a haptic guidance algorithm is superior to training with a conventional joystick. We also provide a case study on two special needs children, under three years old, who learn to make sharp turns during driving, when trained over a five-day period with the force-feedback joystick using the algorithm.

  1. Assessing mouse alternatives to access to computer: a case study of a user with cerebral palsy.

    PubMed

    Pousada, Thais; Pareira, Javier; Groba, Betania; Nieto, Laura; Pazos, Alejandro

    2014-01-01

    The purpose of this study is to describe the process of assessment of three assistive devices to meet the needs of a woman with cerebral palsy (CP) in order to provide her with computer access and use. The user has quadriplegic CP, with anarthria, using a syllabic keyboard. Devices were evaluated through a three-step approach: (a) use of a questionnaire to preselect potential assistive technologies, (b) use of an eTAO tool to determine the effectiveness of each devised, and (c) a conducting semi-structured interview to obtain qualitative data. Touch screen, joystick, and trackball were the preselected devices. The best device that met the user's needs and priorities was joystick. The finding was corroborated by both the eTAO tool and the semi-structured interview. Computers are a basic form of social participation. It is important to consider the special needs and priorities of users and to try different devices when undertaking a device-selection process. Environmental and personal factors have to be considered, as well. This leads to a need to evaluate new tools in order to provide the appropriate support. The eTAO could be a suitable instrument for this purpose. Additional research is also needed to understand how to better match devices with different user populations and how to comprehensively evaluate emerging technologies relative to users with disabilities.

  2. Cardiopulmonary Response to Videogaming: Slaying Monsters Using Motion Sensor Versus Joystick Devices.

    PubMed

    Sherman, Jeffrey D; Sherman, Michael S; Heiman-Patterson, Terry

    2014-10-01

    Replacing physical activity with videogaming has been implicated in causing obesity. Studies have shown that using motion-sensing controllers with activity-promoting videogames expends energy comparable to aerobic exercise; however, effects of motion-sensing controllers have not been examined with traditional (non-exercise-promoting) videogames. We measured indirect calorimetry and heart rate in 14 subjects during rest and traditional videogaming using motion sensor and joystick controllers. Energy expenditure was higher while subjects were playing with the motion sensor (1.30±0.32 kcal/kg/hour) than with the joystick (1.07±0.26 kcal/kg/hour; P<0.01) or resting (0.91±0.24 kcal/kg/hour; P<0.01). Oxygen consumption during videogaming averaged 15.7 percent of predicted maximum for the motion sensor and 11.8 percent of maximum for the joystick. Minute ventilation was higher playing with the motion sensor (10.7±3.5 L/minute) than with the joystick (8.6±1.8 L/minute; P<0.02) or resting (6.7±1.4 L/minute; P<0.001), predominantly because of higher respiratory rates (15.2±4.3 versus 20.3±2.8 versus 20.4±4.2 beats/minute for resting, the joystick, and the motion sensor, respectively; P<0.001); tidal volume did not change significantly. Peak heart rate during gaming was 16.4 percent higher than resting (78.0±12.0) for joystick (90.1±15.0; P=0.002) and 17.4 percent higher for the motion sensor (91.6±14.1; P=0.002); mean heart rate did not differ significantly. Playing with a motion sensor burned significantly more calories than with a joystick, but the energy expended was modest. With both consoles, the increased respiratory rate without increasing tidal volume and the increased peak heart rate without increasing mean heart rate are consistent with psychological stimulation from videogaming, rather than a result of exercise. We conclude that using a motion sensor with traditional videogames does not provide adequate energy expenditure to provide cardiovascular conditioning.

  3. Youth with cerebral palsy with differing upper limb abilities: how do they access computers?

    PubMed

    Davies, T Claire; Chau, Tom; Fehlings, Darcy L; Ameratunga, Shanthi; Stott, N Susan

    2010-12-01

    To identify the current level of awareness of different computer access technologies and the choices made regarding mode of access by youth with cerebral palsy (CP) and their families. Survey. Two tertiary-level rehabilitation centers in New Zealand and Canada. Youth (N=60) with CP, Manual Ability Classification Scale (MACS) levels I to V, age 13 to 25 years. Not applicable. Questionnaire. Fifty (83%) of the 60 youth were aware of at least 1 available assistive technology (AT), such as touch screens and joysticks. However, only 34 youth (57%) were familiar with the accessibility options currently available in the most common operating systems. Thirty-three (94%) of 35 youth who were MACS I and II used a standard mouse and keyboard, while few chose to use assistive technology or accessibility options. In contrast, 10 (40%) of 25 youth who were MACS III to V used a variety of assistive technologies such as touch screens, joysticks, trackballs, and scanning technologies. This group also had the highest use of accessibility options, although only 15 (60%) of the 25 were aware of them. Most youth with CP were aware of, and used, assistive technologies to enhance their computer access but were less knowledgeable about accessibility options. Accessibility options allow users to modify their own computer interface and can thus enhance computer access for youth with CP. Clinicians should be knowledgeable enough to give informed advice in this area of computer access, thus ensuring that all youth with CP can benefit from both AT and accessibility options, as required. Copyright © 2010 American Congress of Rehabilitation Medicine. Published by Elsevier Inc. All rights reserved.

  4. Calibration of a Hall effect displacement measurement system for complex motion analysis using a neural network.

    PubMed

    Northey, G W; Oliver, M L; Rittenhouse, D M

    2006-01-01

    Biomechanics studies often require the analysis of position and orientation. Although a variety of transducer and camera systems can be utilized, a common inexpensive alternative is the Hall effect sensor. Hall effect sensors have been used extensively for one-dimensional position analysis but their non-linear behavior and cross-talk effects make them difficult to calibrate for effective and accurate two- and three-dimensional position and orientation analysis. The aim of this study was to develop and calibrate a displacement measurement system for a hydraulic-actuation joystick used for repetitive motion analysis of heavy equipment operators. The system utilizes an array of four Hall effect sensors that are all active during any joystick movement. This built-in redundancy allows the calibration to utilize fully connected feed forward neural networks in conjunction with a Microscribe 3D digitizer. A fully connected feed forward neural network with one hidden layer containing five neurons was developed. Results indicate that the ability of the neural network to accurately predict the x, y and z coordinates of the joystick handle was good with r(2) values of 0.98 and higher. The calibration technique was found to be equally as accurate when used on data collected 5 days after the initial calibration, indicating the system is robust and stable enough to not require calibration every time the joystick is used. This calibration system allowed an infinite number of joystick orientations and positions to be found within the range of joystick motion.

  5. Interacting with notebook input devices: an analysis of motor performance and users' expertise.

    PubMed

    Sutter, Christine; Ziefle, Martina

    2005-01-01

    In the present study the usability of two different types of notebook input devices was examined. The independent variables were input device (touchpad vs. mini-joystick) and user expertise (expert vs. novice state). There were 30 participants, of whom 15 were touchpad experts and the other 15 were mini-joystick experts. The experimental tasks were a point-click task (Experiment 1) and a point-drag-drop task (Experiment 2). Dependent variables were the time and accuracy of cursor control. To assess carryover effects, we had the participants complete both experiments, using not only the input device for which they were experts but also the device for which they were novices. Results showed the touchpad performance to be clearly superior to mini-joystick performance. Overall, experts showed better performance than did novices. The significant interaction of input device and expertise showed that the use of an unknown device is difficult, but only for touchpad experts, who were remarkably slower and less accurate when using a mini-joystick. Actual and potential applications of this research include an evaluation of current notebook input devices. The outcomes allow ergonomic guidelines to be derived for optimized usage and design of the mini-joystick and touchpad devices.

  6. Haptic augmentation of science instruction: Does touch matter?

    NASA Astrophysics Data System (ADS)

    Jones, M. Gail; Minogue, James; Tretter, Thomas R.; Negishi, Atsuko; Taylor, Russell

    2006-01-01

    This study investigated the impact of haptic augmentation of a science inquiry program on students' learning about viruses and nanoscale science. The study assessed how the addition of different types of haptic feedback (active touch and kinesthetic feedback) combined with computer visualizations influenced middle and high school students' experiences. The influences of a PHANToM (a sophisticated haptic desktop device), a Sidewinder (a haptic gaming joystick), and a mouse (no haptic feedback) interface were compared. The levels of engagement in the instruction and students' attitudes about the instructional program were assessed using a combination of constructed response and Likert scale items. Potential cognitive differences were examined through an analysis of spontaneously generated analogies that appeared during student discourse. Results showed that the addition of haptic feedback from the haptic-gaming joystick and the PHANToM provided a more immersive learning environment that not only made the instruction more engaging but may also influence the way in which the students construct their understandings about abstract science concepts.

  7. A robotic wheelchair trainer: design overview and a feasibility study

    PubMed Central

    2010-01-01

    Background Experiencing independent mobility is important for children with a severe movement disability, but learning to drive a powered wheelchair can be labor intensive, requiring hand-over-hand assistance from a skilled therapist. Methods To improve accessibility to training, we developed a robotic wheelchair trainer that steers itself along a course marked by a line on the floor using computer vision, haptically guiding the driver's hand in appropriate steering motions using a force feedback joystick, as the driver tries to catch a mobile robot in a game of "robot tag". This paper provides a detailed design description of the computer vision and control system. In addition, we present data from a pilot study in which we used the chair to teach children without motor impairment aged 4-9 (n = 22) to drive the wheelchair in a single training session, in order to verify that the wheelchair could enable learning by the non-impaired motor system, and to establish normative values of learning rates. Results and Discussion Training with haptic guidance from the robotic wheelchair trainer improved the steering ability of children without motor impairment significantly more than training without guidance. We also report the results of a case study with one 8-year-old child with a severe motor impairment due to cerebral palsy, who replicated the single-session training protocol that the non-disabled children participated in. This child also improved steering ability after training with guidance from the joystick by an amount even greater than the children without motor impairment. Conclusions The system not only provided a safe, fun context for automating driver's training, but also enhanced motor learning by the non-impaired motor system, presumably by demonstrating through intuitive movement and force of the joystick itself exemplary control to follow the course. The case study indicates that a child with a motor system impaired by CP can also gain a short-term benefit from driver's training with haptic guidance. PMID:20707886

  8. A robotic wheelchair trainer: design overview and a feasibility study.

    PubMed

    Marchal-Crespo, Laura; Furumasu, Jan; Reinkensmeyer, David J

    2010-08-13

    Experiencing independent mobility is important for children with a severe movement disability, but learning to drive a powered wheelchair can be labor intensive, requiring hand-over-hand assistance from a skilled therapist. To improve accessibility to training, we developed a robotic wheelchair trainer that steers itself along a course marked by a line on the floor using computer vision, haptically guiding the driver's hand in appropriate steering motions using a force feedback joystick, as the driver tries to catch a mobile robot in a game of "robot tag". This paper provides a detailed design description of the computer vision and control system. In addition, we present data from a pilot study in which we used the chair to teach children without motor impairment aged 4-9 (n = 22) to drive the wheelchair in a single training session, in order to verify that the wheelchair could enable learning by the non-impaired motor system, and to establish normative values of learning rates. Training with haptic guidance from the robotic wheelchair trainer improved the steering ability of children without motor impairment significantly more than training without guidance. We also report the results of a case study with one 8-year-old child with a severe motor impairment due to cerebral palsy, who replicated the single-session training protocol that the non-disabled children participated in. This child also improved steering ability after training with guidance from the joystick by an amount even greater than the children without motor impairment. The system not only provided a safe, fun context for automating driver's training, but also enhanced motor learning by the non-impaired motor system, presumably by demonstrating through intuitive movement and force of the joystick itself exemplary control to follow the course. The case study indicates that a child with a motor system impaired by CP can also gain a short-term benefit from driver's training with haptic guidance.

  9. Note on hand use in the manipulation of joysticks by rhesus monkeys (Macaca mulatta) and chimpanzees (Pan troglodytes)

    NASA Technical Reports Server (NTRS)

    Hopkins, William D.; Washburn, David A.; Rumbaugh, Duane M.

    1989-01-01

    MacNeilage et al. (1987) have proposed that nonhuman primate handedness may be contingent on the specific task requirements, with visual-spatial tasks yielding left-hand preferences and fine-motor tasks producing right-hand preferences. This study reports hand preferences in the manipulation of joysticks by 2 rhesus monkeys and 3 chimpanzees. Reach data were also collected for comparison with preference data for manipulation of the joystick. The data indicated that all 5 subjects demonstrated significant right-hand preferences in manipulating the joystick. In contrast, no significant hand preferences were found for the reach data. Reaction-time data also indicated that the right hand could perform a perceptual-motor task better than the left hand in all 5 subjects. Overall, the data indicate that reach tasks may not be sensitive enough measures to produce reliable hand preferences, whereas tasks that assess fine-motor control produce significant hand preferences.

  10. Investigations of rhesus monkey video-task performance: evidence for enrichment

    NASA Technical Reports Server (NTRS)

    Washburn, D. A.; Rumbaugh, D. M.

    1992-01-01

    We have developed the Language Research Center's Computerized Test System (LRC-CTS) for psychological research. Basically, the LRC-CTS is a battery of software tasks--computerized versions of many of the classic testing paradigms of cognitive and comparative psychology--and the hardware required to administer them. An XT- or 386-compatible computer is connected to a color monitor, onto which computer-generated stimuli are presented. Sound feedback is delivered through an external speaker/amplifier, and a joystick is used as an input device. The animals reach through the mesh of their home cages to manipulate the joystick, which causes isomorphic movements of a cursor on the screen thereby allowing animals to respond according to the varied demands of the tasks. Correct responses are rewarded with a fruit-flavored chow pellet. Using this technology, we have trained and tested rhesus monkeys, a variety of apes, human adults, and normally developing or mentally retarded human children. Other labs using the LRC-CTS are beginning to report encouraging results with other monkey species as well. From this research, a number of interesting and important psychological findings have resulted. In the present paper, however, evidence will be reviewed which suggests that the LRC-CTS is an effective means of providing environmental enrichment to singly housed rhesus monkeys.

  11. Wearable wireless User Interface Cursor-Controller (UIC-C).

    PubMed

    Marjanovic, Nicholas; Kerr, Kevin; Aranda, Ricardo; Hickey, Richard; Esmailbeigi, Hananeh

    2017-07-01

    Controlling a computer or a smartphone's cursor allows the user to access a world full of information. For millions of people with limited upper extremities motor function, controlling the cursor becomes profoundly difficult. Our team has developed the User Interface Cursor-Controller (UIC-C) to assist the impaired individuals in regaining control over the cursor. The UIC-C is a hands-free device that utilizes the tongue muscle to control the cursor movements. The entire device is housed inside a subject specific retainer. The user maneuvers the cursor by manipulating a joystick imbedded inside the retainer via their tongue. The joystick movement commands are sent to an electronic device via a Bluetooth connection. The device is readily recognizable as a cursor controller by any Bluetooth enabled electronic device. The device testing results have shown that the time it takes the user to control the cursor accurately via the UIC-C is about three times longer than a standard computer mouse controlled via the hand. The device does not require any permanent modifications to the body; therefore, it could be used during the period of acute rehabilitation of the hands. With the development of modern smart homes, and enhancement electronics controlled by the computer, UIC-C could be integrated into a system that enables individuals with permanent impairment, the ability to control the cursor. In conclusion, the UIC-C device is designed with the goal of allowing the user to accurately control a cursor during the periods of either acute or permanent upper extremities impairment.

  12. Development of a dual joystick-controlled laser trapping and cutting system for optical micromanipulation of chromosomes inside living cells.

    PubMed

    Harsono, Marcellinus S; Zhu, Qingyuan; Shi, Linda Z; Duquette, Michelle; Berns, Michael W

    2013-02-01

    A multi-joystick robotic laser microscope system used to control two optical traps (tweezers) and one laser scissors has been developed for subcellular organelle manipulation. The use of joysticks has provided a "user-friendly" method for both trapping and cutting of organelles such as chromosomes in live cells. This innovative design has enabled the clean severing of chromosome arms using the laser scissors as well as the ability to easily hold and pull the severed arm using the laser tweezers. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  13. Hand controller commonality evaluation process

    NASA Technical Reports Server (NTRS)

    Stuart, Mark A.; Bierschwale, John M.; Wilmington, Robert P.; Adam, Susan C.; Diaz, Manuel F.; Jensen, Dean G.

    1990-01-01

    A hand controller evaluation process has been developed to determine the appropriate hand controller configurations for supporting remotely controlled devices. These devices include remote manipulator systems (RMS), dexterous robots, and remotely-piloted free flyers. Standard interfaces were developed to evaluate six different hand controllers in three test facilities including dynamic computer simulations, kinematic computer simulations, and physical simulations. The hand controllers under consideration were six degree-of-freedom (DOF) position and rate minimaster and joystick controllers, and three-DOF rate controllers. Task performance data, subjective comments, and anthropometric data obtained during tests were used for controller configuration recommendations to the SSF Program.

  14. Training toddlers seated on mobile robots to drive indoors amidst obstacles.

    PubMed

    Chen, Xi; Ragonesi, Christina; Galloway, James C; Agrawal, Sunil K

    2011-06-01

    Mobility is a causal factor in development. Children with mobility impairments may rely upon power mobility for independence and thus require advanced driving skills to function independently. Our previous studies show that while infants can learn to drive directly to a goal using conventional joysticks in several months of training, they are unable in this timeframe to acquire the advanced skill to avoid obstacles while driving. Without adequate driving training, children are unable to explore the environment safely, the consequences of which may in turn increase their risk for developmental delay. The goal of this research therefore is to train children seated on mobile robots to purposefully and safely drive indoors. In this paper, we present results where ten typically-developing toddlers are trained to drive a robot within an obstacle course. We also report a case study with a toddler with spina-bifida who cannot independently walk. Using algorithms based on artificial potential fields to avoid obstacles, we create force field on the joystick that trains the children to navigate while avoiding obstacles. In this "assist-as-needed" approach, if the child steers the joystick outside a force tunnel centered on the desired direction, the driver experiences a bias force on the hand. Our results suggest that the use of a force-feedback joystick may yield faster learning than the use of a conventional joystick.

  15. The Influence of Depression on Cognitive Control: Disambiguating Approach and Avoidance Tendencies.

    PubMed

    Huang, He; Movellan, Javier; Paulus, Martin P; Harlé, Katia M

    2015-01-01

    Dysfunctions of approach and avoidance motivation play an important role in depression, which in turn may affect cognitive control, i.e., the ability to regulate thoughts and action to achieve internal goals. We use a novel experimental paradigm, i.e. a computer simulated driving-task, to study the impact of depression on cognitive control by measuring approach and avoidance actions in continuous time. In this task, 39 subjects with minimal to severe depression symptoms were instructed to use a joystick to move a virtual car as quickly as possible to a target point without crossing a stop-sign or crashing into a wall. We recorded their continuous actions on a joystick and found that depression 1) leads to further stopping distance to task target; and 2) increases the magnitude of late deceleration (avoidance) but not early acceleration (approach), which was only observed in the stop-sign condition. Taken together, these results are consistent with the hypothesis that depressed individuals have greater avoidance motivation near stopping target, but are minimally affected by approach motivation.

  16. View of Commander (CDR) Scott Altman working on the Flight Deck

    NASA Image and Video Library

    2009-05-21

    S125-E-013081 (21 May 2009) --- Occupying the commander?s station, astronaut Scott Altman, STS-125 commander, uses the Portable In-Flight Landing Operations Trainer (PILOT) on the flight deck of the Earth-orbiting Space Shuttle Atlantis. PILOT consists of a laptop computer and a joystick system, which helps to maintain a high level of proficiency for the end-of-mission approach and landing tasks required to bring the shuttle safely back to Earth.

  17. View of STS-125 Crew Members working on the Flight Deck

    NASA Image and Video Library

    2009-05-21

    S125-E-013050 (21 May 2009) --- Occupying the commander?s station, astronaut Gregory C. Johnson, STS-125 pilot, uses the Portable In-Flight Landing Operations Trainer (PILOT) on the flight deck of the Earth-orbiting Space Shuttle Atlantis. PILOT consists of a laptop computer and a joystick system, which helps to maintain a high level of proficiency for the end-of-mission approach and landing tasks required to bring the shuttle safely back to Earth.

  18. View of Pilot Gregory Johnson working on the Flight Deck

    NASA Image and Video Library

    2009-05-21

    S125-E-013040 (21 May 2009) --- Occupying the commander?s station, astronaut Gregory C. Johnson, STS-125 pilot, uses the Portable In-Flight Landing Operations Trainer (PILOT) on the flight deck of the Earth-orbiting Space Shuttle Atlantis. PILOT consists of a laptop computer and a joystick system, which helps to maintain a high level of proficiency for the end-of-mission approach and landing tasks required to bring the shuttle safely back to Earth.

  19. Optimal digital filtering for tremor suppression.

    PubMed

    Gonzalez, J G; Heredia, E A; Rahman, T; Barner, K E; Arce, G R

    2000-05-01

    Remote manually operated tasks such as those found in teleoperation, virtual reality, or joystick-based computer access, require the generation of an intermediate electrical signal which is transmitted to the controlled subsystem (robot arm, virtual environment, or a cursor in a computer screen). When human movements are distorted, for instance, by tremor, performance can be improved by digitally filtering the intermediate signal before it reaches the controlled device. This paper introduces a novel tremor filtering framework in which digital equalizers are optimally designed through pursuit tracking task experiments. Due to inherent properties of the man-machine system, the design of tremor suppression equalizers presents two serious problems: 1) performance criteria leading to optimizations that minimize mean-squared error are not efficient for tremor elimination and 2) movement signals show ill-conditioned autocorrelation matrices, which often result in useless or unstable solutions. To address these problems, a new performance indicator in the context of tremor is introduced, and the optimal equalizer according to this new criterion is developed. Ill-conditioning of the autocorrelation matrix is overcome using a novel method which we call pulled-optimization. Experiments performed with artificially induced vibrations and a subject with Parkinson's disease show significant improvement in performance. Additional results, along with MATLAB source code of the algorithms, and a customizable demo for PC joysticks, are available on the Internet at http:¿tremor-suppression.com.

  20. The 3D Human Motion Control Through Refined Video Gesture Annotation

    NASA Astrophysics Data System (ADS)

    Jin, Yohan; Suk, Myunghoon; Prabhakaran, B.

    In the beginning of computer and video game industry, simple game controllers consisting of buttons and joysticks were employed, but recently game consoles are replacing joystick buttons with novel interfaces such as the remote controllers with motion sensing technology on the Nintendo Wii [1] Especially video-based human computer interaction (HCI) technique has been applied to games, and the representative game is 'Eyetoy' on the Sony PlayStation 2. Video-based HCI technique has great benefit to release players from the intractable game controller. Moreover, in order to communicate between humans and computers, video-based HCI is very crucial since it is intuitive, easy to get, and inexpensive. On the one hand, extracting semantic low-level features from video human motion data is still a major challenge. The level of accuracy is really dependent on each subject's characteristic and environmental noises. Of late, people have been using 3D motion-capture data for visualizing real human motions in 3D space (e.g, 'Tiger Woods' in EA Sports, 'Angelina Jolie' in Bear-Wolf movie) and analyzing motions for specific performance (e.g, 'golf swing' and 'walking'). 3D motion-capture system ('VICON') generates a matrix for each motion clip. Here, a column is corresponding to a human's sub-body part and row represents time frames of data capture. Thus, we can extract sub-body part's motion only by selecting specific columns. Different from low-level feature values of video human motion, 3D human motion-capture data matrix are not pixel values, but is closer to human level of semantics.

  1. Human behavior and human performance: Psychomotor demands

    NASA Technical Reports Server (NTRS)

    1992-01-01

    The results of several experiments are presented in abstract form. These studies are critical for the interpretation and acceptance of flight based science to be conducted by the Behavior and Performance project. Some representative titles are as follow: External audio for IBM/PC compatible computers; A comparative assessment of psychomotor performance (target prediction by humans and macaques); Response path (a dependent measure for computer maze solving and other tasks); Behavioral asymmetries of psychomotor performance in Rhesus monkey (a dissociation between hand preference and skill); Testing primates with joystick based automated apparatus; and Environmental enrichment and performance assessment for ground or flight based research with primates;

  2. View of Pilot Gregory Johnson working on the Flight Deck

    NASA Image and Video Library

    2009-05-21

    S125-E-013042 (21 May 2009) --- Occupying the commander?s station, astronaut Gregory C. Johnson, STS-125 pilot, uses the Portable In-Flight Landing Operations Trainer (PILOT) on the flight deck of the Earth-orbiting Space Shuttle Atlantis. PILOT consists of a laptop computer and a joystick system, which helps to maintain a high level of proficiency for the end-of-mission approach and landing tasks required to bring the shuttle safely back to Earth. Astronaut Scott Altman, commander, looks on.

  3. Behavioral asymmetries of psychomotor performance in rhesus monkeys (Macaca mulatta) - A dissociation between hand preference and skill

    NASA Technical Reports Server (NTRS)

    Hopkins, William D.; Washburn, David A.; Berke, Leslie; Williams, Mary

    1992-01-01

    Hand preferences were recorded for 35 rhesus monkeys (Macaca mulatta) as they manipulated a joystick in response to 2 computerized tasks. These preferences were then used to contrast 8 left- and 10 right-handed subjects on performance measures of hand skill. Individual hand preferences were found, but no significant population asymmetry was observed across the sample. However, the performance data reveal substantial benefits of right-handedness for joystick manipulation, as this group of monkeys mastered the 2 psychomotor tasks significantly faster than did their left-handed counterparts. The data support earlier reports of a right-hand advantage for joystick manipulation and also support the importance of distinguishing between hand preference and manual performance in research on functional asymmetries.

  4. Joystick With Cable Springs Offers Better Feel

    NASA Technical Reports Server (NTRS)

    Kerley, James; Ecklund, Wayne

    1992-01-01

    Improved joystick allows motion in 6 degrees of freedom, biased toward central position and orientation by 16 segments of cable serving as springs. Improvement in feel and control results from nonlinear compliance of cable-spring assembly. Nonlinear variations accommodate natural reactions of hand and brain. Operator functions as part of feedback control loop. More comfortable, increases ability to exert control and reduces fatigue.

  5. Joystick-controlled video console game practice for developing power wheelchairs users' indoor driving skills.

    PubMed

    Huang, Wei Pin; Wang, Chia Cheng; Hung, Jo Hua; Chien, Kai Chun; Liu, Wen-Yu; Cheng, Chih-Hsiu; Ng, How-Hing; Lin, Yang-Hua

    2015-02-01

    [Purpose] This study aimed to determine the effectiveness of joystick-controlled video console games in enhancing subjects' ability to control power wheelchairs. [Subjects and Methods] Twenty healthy young adults without prior experience of driving power wheelchairs were recruited. Four commercially available video games were used as training programs to practice joystick control in catching falling objects, crossing a river, tracing the route while floating on a river, and navigating through a garden maze. An indoor power wheelchair driving test, including straight lines, and right and left turns, was completed before and after the video game practice, during which electromyographic signals of the upper limbs were recorded. The paired t-test was used to compare the differences in driving performance and muscle activities before and after the intervention. [Results] Following the video game intervention, participants took significantly less time to complete the course, with less lateral deviation when turning the indoor power wheelchair. However, muscle activation in the upper limbs was not significantly affected. [Conclusion] This study demonstrates the feasibility of using joystick-controlled commercial video games to train individuals in the control of indoor power wheelchairs.

  6. Potential of a suite of robot/computer-assisted motivating systems for personalized, home-based, stroke rehabilitation.

    PubMed

    Johnson, Michelle J; Feng, Xin; Johnson, Laura M; Winters, Jack M

    2007-03-01

    There is a need to improve semi-autonomous stroke therapy in home environments often characterized by low supervision of clinical experts and low extrinsic motivation. Our distributed device approach to this problem consists of an integrated suite of low-cost robotic/computer-assistive technologies driven by a novel universal access software framework called UniTherapy. Our design strategy for personalizing the therapy, providing extrinsic motivation and outcome assessment is presented and evaluated. Three studies were conducted to evaluate the potential of the suite. A conventional force-reflecting joystick, a modified joystick therapy platform (TheraJoy), and a steering wheel platform (TheraDrive) were tested separately with the UniTherapy software. Stroke subjects with hemiparesis and able-bodied subjects completed tracking activities with the devices in different positions. We quantify motor performance across subject groups and across device platforms and muscle activation across devices at two positions in the arm workspace. Trends in the assessment metrics were consistent across devices with able-bodied and high functioning strokes subjects being significantly more accurate and quicker in their motor performance than low functioning subjects. Muscle activation patterns were different for shoulder and elbow across different devices and locations. The Robot/CAMR suite has potential for stroke rehabilitation. By manipulating hardware and software variables, we can create personalized therapy environments that engage patients, address their therapy need, and track their progress. A larger longitudinal study is still needed to evaluate these systems in under-supervised environments such as the home.

  7. Neuroelectric Virtual Devices

    NASA Technical Reports Server (NTRS)

    Wheeler, Kevin; Jorgensen, Charles

    2000-01-01

    This paper presents recent results in neuroelectric pattern recognition of electromyographic (EMG) signals used to control virtual computer input devices. The devices are designed to substitute for the functions of both a traditional joystick and keyboard entry method. We demonstrate recognition accuracy through neuroelectric control of a 757 class simulation aircraft landing at San Francisco International Airport using a virtual joystick as shown. This is accomplished by a pilot closing his fist in empty air and performing control movements that are captured by a dry electrode array on the arm which are then analyzed and routed through a flight director permitting full pilot outer loop control of the simulation. We then demonstrate finer grain motor pattern recognition through a virtual keyboard by having a typist tap his traders on a typical desk in a touch typist position. The EMG signals are then translated to keyboard presses and displayed. The paper describes the bioelectric pattern recognition methodology common to both examples. Figure 2 depicts raw EMG data from typing, the numeral '8' and the numeral '9'. These two gestures are very close in appearance and statistical properties yet are distinguishable by our hidden Kharkov model algorithms. Extensions of this work to NASA emissions and robotic control are considered.

  8. Dismounted Warrior Network Experiments

    DTIC Science & Technology

    2000-11-01

    Foxtrot Locomotion Human Joystick ODT Joystick Foot Pedal + Head Orientation Visual Display Wireless HMD 4 Projection Desktop Single Screens (WISE... Biomechanics DI-Guy JackML DI-Guy Table 1. VICs Comparison Matrix VIC Alpha is the Dismounted Soldier Simulation (DSS) system developed by Veda, Inc. under a...using a pressure sensitive foot pedal . The user’s head is tracked with a magnetic sensor and is used to control steering through the environment. A

  9. STS-42 Commander Grabe works with MWPE at IML-1 Rack 8 aboard OV-103

    NASA Technical Reports Server (NTRS)

    1992-01-01

    STS-42 Commander Ronald J. Grabe works with the Mental Workload and Performance Evaluation Experiment (MWPE) (portable laptop computer, keyboard cursor keys, a two-axis joystick, and a track ball) at Rack 8 in the International Microgravity Laboratory 1 (IML-1) module. The test was designed as a result of difficulty experienced by crewmembers working at a computer station on a previous Space Shuttle mission. The problem was due to the workstation's design being based on Earth-bound conditions with the operator in a typical one-G standing position. For STS-42, the workstation was redesigned to evaluate the effects of microgravity on the ability of crewmembers to interact with a computer workstation. Information gained from this experiment will be used to design workstations for future Spacelab missions and Space Station Freedom (SSF).

  10. Computer-task testing of rhesus monkeys (Macaca mulatta) in the social milieu.

    PubMed

    Washburn, D A; Harper, S; Rumbaugh, D M

    1994-07-01

    Previous research has demonstrated that a behavior and performance testing paradigm, in which rhesus monkeys (Macaca mulatta) manipulate a joystick to respond to computer-generated stimuli, provides environmental enrichment and supports the psychological well-being of captive research animals. The present study was designed to determine whether computer-task activity would be affected by pair-housing animals that had previously been tested only in their single-animal home cages. No differences were observed in productivity or performance levels as a function of housing condition, even when the animals were required to "self-identify" prior to performing each trial. The data indicate that cognitive challenge and control are as preferred by the animals as social opportunities, and that, together with comfort/health considerations, each must be addressed for the assurance of psychological well-being.

  11. Feedback Control for a Smart Wheelchair Trainer Based on the Kinect Sensor

    NASA Astrophysics Data System (ADS)

    Darling, Aurelia McLaughlin

    This thesis describes a Microsoft Kinect-based feedback controller for a robot-assisted powered wheelchair trainer for children with a severe motor and/or cognitive disability. In one training mode, "computer gaming" mode, the wheelchair is allowed to rotate left and right while the children use a joystick to play video games shown on a screen in front of them. This enables them to learn the use of the joystick in a motivating environment, while experiencing the sensation and dynamics of turning in a safe setting. During initial pilot testing of the device, it was found that the wheelchair would creep forward while children were playing the games. This thesis presents a mathematical model of the wheelchair dynamics that explains the origin of the creep as a center of gravity offset from the wheel axis or a mismatch of the torques applied to the chair. Given these possible random perturbations, a feedback controller was developed to cancel these effects, correcting the system creep. The controller uses a Microsoft Kinect sensor to detect the distance to the screen displaying the computer game, as well as the left-right position (parallel parking concept) with respect to the screen, and then adjusts the wheel torque commands based on this measurement. We show through experimental testing that this controller effectively stops the creep. An added benefit of the feedback controller is that it approximates a washout filter, such as those used in aircraft simulators, to convey a more realistic sense of forward/backward motion during game play.

  12. Potential of a suite of robot/computer-assisted motivating systems for personalized, home-based, stroke rehabilitation

    PubMed Central

    Johnson, Michelle J; Feng, Xin; Johnson, Laura M; Winters, Jack M

    2007-01-01

    Background There is a need to improve semi-autonomous stroke therapy in home environments often characterized by low supervision of clinical experts and low extrinsic motivation. Our distributed device approach to this problem consists of an integrated suite of low-cost robotic/computer-assistive technologies driven by a novel universal access software framework called UniTherapy. Our design strategy for personalizing the therapy, providing extrinsic motivation and outcome assessment is presented and evaluated. Methods Three studies were conducted to evaluate the potential of the suite. A conventional force-reflecting joystick, a modified joystick therapy platform (TheraJoy), and a steering wheel platform (TheraDrive) were tested separately with the UniTherapy software. Stroke subjects with hemiparesis and able-bodied subjects completed tracking activities with the devices in different positions. We quantify motor performance across subject groups and across device platforms and muscle activation across devices at two positions in the arm workspace. Results Trends in the assessment metrics were consistent across devices with able-bodied and high functioning strokes subjects being significantly more accurate and quicker in their motor performance than low functioning subjects. Muscle activation patterns were different for shoulder and elbow across different devices and locations. Conclusion The Robot/CAMR suite has potential for stroke rehabilitation. By manipulating hardware and software variables, we can create personalized therapy environments that engage patients, address their therapy need, and track their progress. A larger longitudinal study is still needed to evaluate these systems in under-supervised environments such as the home. PMID:17331243

  13. Control order and visuomotor strategy development for joystick-steered underground shuttle cars.

    PubMed

    Cloete, Steven; Zupanc, Christine; Burgess-Limerick, Robin; Wallis, Guy

    2014-09-01

    In this simulator-based study, we aimed to quantify performance differences between joystick steering systems using first-order and second-order control, which are used in underground coal mining shuttle cars. In addition, we conducted an exploratory analysis of how users of the more difficult, second-order system changed their behavior over time. Evidence from the visuomotor control literature suggests that higher-order control devices are not intuitive, which could pose a significant risk to underground mine personnel, equipment, and infrastructure. Thirty-six naive participants were randomly assigned to first- and second-order conditions and completed three experimental trials comprising sequences of 90 degrees turns in a virtual underground mine environment, with velocity held constant at 9 km/h(-1). Performance measures were lateral deviation, steering angle variability, high-frequency steering content, joystick activity, and cumulative time in collision with the virtual mine wall. The second-order control group exhibited significantly poorer performance for all outcome measures. In addition, a series of correlation analyses revealed that changes in strategy were evident in the second-order group but not the first-order group. Results were consistent with previous literature indicating poorer performance with higher-order control devices and caution against the adoption of the second-order joystick system for underground shuttle cars. Low-cost, portable simulation platforms may provide an effective basis for operator training and recruitment.

  14. Testing primates with joystick-based automated apparatus - Lessons from the Language Research Center's Computerized Test System

    NASA Technical Reports Server (NTRS)

    Washburn, David A.; Rumbaugh, Duane M.

    1992-01-01

    Nonhuman primates provide useful models for studying a variety of medical, biological, and behavioral topics. Four years of joystick-based automated testing of monkeys using the Language Research Center's Computerized Test System (LRC-CTS) are examined to derive hints and principles for comparable testing with other species - including humans. The results of multiple parametric studies are reviewed, and reliability data are presented to reveal the surprises and pitfalls associated with video-task testing of performance.

  15. Teaching Surgical Hysteroscopy with a Computer

    PubMed

    Lefebvre; Cote; Lefebvre

    1996-08-01

    Using a hysteroscope can be simulated on a computer. It will improve physician training by measuring basic knowledge and abilities, allow different interventions and anatomic variations, minimize the trauma of surgical intervention, and reduce operative casualties. An integrated questionnaire covers instrumentation, fluid infusion, power source, indications and preparation for endometrial ablation, surgical techniques, and complications to evaluate the user's knowledge. The operation simulation then proceeds. In the endometrial cavity, by virtual simulation, the operating field should appear in real time to allow physicians to adapt the trajectory of the instruments. The computer is an IBM PC compatible. We use a modified joystick with optical encoders to know the instrument position. The simulation can be repeated as desired. An evaluation system is integrated in the software to keep the user informed on the amount of burn area(s) that have been completed. This prototype model is available.

  16. A comparison of position and rate control for telemanipulations with consideration of manipulator system dynamics

    NASA Technical Reports Server (NTRS)

    Kim, Won S.; Tendick, Frank; Stark, Lawrence W.; Ellis, Stephen R.

    1987-01-01

    Position and rate control are the two common manual control modes in teleoperations. Human operator performance using the two modes is evaluated and compared. Simulated three-axis pick-and-place operations are used as the primary task for evaluation. First, ideal position and rate control are compared by considering several factors, such as joystick gain, joystick type, display mode, task, and manipulator work space size. Then the effects of the manipulator system dynamics are investigated by varying the natural frequency and speed limit. Experimental results show that ideal position control is superior to ideal rate control, regardless of joystick type or display mode, when the manipulation work space is small or comparable to the human operator's control space. Results also show that when the manipulator system is slow, the superiority of position control disappears. Position control is recommended for small-work-space telemanipulation tasks, while rate control is recommended for slow wide-work-space telemanipulation tasks.

  17. Method and Apparatus for Encouraging Physiological Self-Regulation Through Modulation of an Operator's Control Input to a Video Game or Training Simulator

    NASA Technical Reports Server (NTRS)

    Palsson, Olafur S. (Inventor); Harris, Randall L., Sr. (Inventor); Pope, Alan T. (Inventor)

    2002-01-01

    Apparatus and methods for modulating the control authority (i.e., control function) of a computer simulation or game input device (e.g., joystick, button control) using physiological information so as to affect the user's ability to impact or control the simulation or game with the input device. One aspect is to use the present invention, along with a computer simulation or game, to affect physiological state or physiological self-regulation according to some programmed criterion (e.g., increase, decrease, or maintain) in order to perform better at the game task. When the affected physiological state or physiological self-regulation is the target of self-regulation or biofeedback training, the simulation or game play reinforces therapeutic changes in the physiological signal(s).

  18. Off-road machine controls: investigating the risk of carpal tunnel syndrome.

    PubMed

    Oliver, M; Rickards, J; Biden, E

    2000-11-01

    Occupationally induced hand and wrist repetitive strain injuries (RSI) such as carpal tunnel syndrome (CTS) are a growing problem in North America. The purpose of this investigation was to apply a modification of the wrist flexion/ extension models of Armstrong and Chaffin (1978, 1979) to determine if joystick controller use in off-road machines could contribute to the development of CTS. A construction equipment cab in the laboratory was instrumented to allow force, displacement and angle measurements from 10 operators while they completed an approximately 30-min joystick motion protocol. The investigation revealed that both the external fingertip and predicted internal wrist forces resulting from the use of these joysticks were very low, indicating that the CTS risk associated with this factor was slight. However, the results also indicated that, particularly for the 'forward' and 'left' right side motions and for all left side motions, force was exerted by other portions of the fingers and hand, thereby under-predicting the tendon tension and internal wrist forces. Wrist angles observed were highest for motions that moved the joysticks to the sides rather than front to back. Thus, the 'right' and 'left' motions for both hands posed a higher risk for CTS development. When the right hand moved into the 'right' position and the left hand moved into the 'left' position, the wrist went into extension in both cases. Results indicate that neither learning nor fatigue affected the results.

  19. A university teaching simulation facility

    NASA Technical Reports Server (NTRS)

    Stark, Lawrence; Kim, Won-Soo; Tendick, Frank; Tyler, Mitchell; Hannaford, Blake; Barakat, Wissam; Bergengruen, Olaf; Braddi, Louis; Eisenberg, Joseph; Ellis, Stephen

    1987-01-01

    An experimental telerobotics (TR) simulation is described suitable for studying human operator (HO) performance. Simple manipulator pick-and-place and tracking tasks allowed quantitative comparison of a number of calligraphic display viewing conditions. A number of control modes could be compared in this TR simulation, including displacement, rate, and acceleratory control using position and force joysticks. A homeomorphic controller turned out to be no better than joysticks; the adaptive properties of the HO can apparently permit quite good control over a variety of controller configurations and control modes. Training by optimal control example seemed helpful in preliminary experiments.

  20. Virtual reality body motion induced navigational controllers and their effects on simulator sickness and pathfinding.

    PubMed

    Aldaba, Cassandra N; White, Paul J; Byagowi, Ahmad; Moussavi, Zahra

    2017-07-01

    Virtual reality (VR) navigation is usually constrained by plausible simulator sickness (SS) and intuitive user interaction. The paper reports on the use of four different degrees of body motion induced navigational VR controllers, a TiltChair, omni-directional treadmill, a manual wheelchair joystick (VRNChair), and a joystick in relation to a participant's SS occurrence and a controller's intuitive utilization. Twenty young adult participants utilized all controllers to navigate through the same VR task environment in separate sessions. Throughout the sessions, SS occurrence was measured from a severity score by a standard SS questionnaire and from body sway by a center of pressure path length with eyes opened and closed. SS occurrence did not significantly differ among the controllers. However, time spent in VR significantly contributed to SS occurrence; hence, a few breaks to minimize SS should be interjected throughout a VR task. For all task trials, we recorded the participant's travel trajectories to investigate each controller's intuitive utilization from a computed traversed distance. Shorter traversed distances indicated that participants intuitively utilized the TiltChair with a slower speed; while longer traversed distances indicated participants struggled to utilize the omni-directional treadmill with a unnaturalistic stimulation of gait. Therefore, VR navigation should use technologies best suited for the intended age group that minimizes SS, and produces intuitive interactions for the participants.

  1. Effects of training pre-movement sensorimotor rhythms on behavioral performance

    NASA Astrophysics Data System (ADS)

    McFarland, Dennis J.; Sarnacki, William A.; Wolpaw, Jonathan R.

    2015-12-01

    Objective. Brain-computer interface (BCI) technology might contribute to rehabilitation of motor function. This speculation is based on the premise that modifying the electroencephalographic (EEG) activity will modify behavior, a proposition for which there is limited empirical data. The present study asked whether learned modulation of pre-movement sensorimotor rhythm (SMR) activity can affect motor performance in normal human subjects. Approach. Eight individuals first performed a joystick-based cursor-movement task with variable warning periods. Targets appeared randomly on a video monitor and subjects moved the cursor to the target and pressed a select button within 2 s. SMR features in the pre-movement EEG that correlated with performance speed and accuracy were identified. The subjects then learned to increase or decrease these features to control a two-target BCI task. Following successful BCI training, they were asked to increase or decrease SMR amplitude in order to initiate the joystick task. Main results. After BCI training, pre-movement SMR amplitude was correlated with performance in subjects with initial poor performance: lower amplitude was associated with faster and more accurate movement. The beneficial effect on performance of lower SMR amplitude was greater in subjects with lower initial performance levels. Significance. These results indicate that BCI-based SMR training can affect a standard motor behavior. They provide a rationale for studies that integrate such training into rehabilitation protocols and examine its capacity to enhance restoration of useful motor function.

  2. Circling motion and screen edges as an alternative input method for on-screen target manipulation.

    PubMed

    Ka, Hyun W; Simpson, Richard C

    2017-04-01

    To investigate a new alternative interaction method, called circling interface, for manipulating on-screen objects. To specify a target, the user makes a circling motion around the target. To specify a desired pointing command with the circling interface, each edge of the screen is used. The user selects a command before circling the target. To evaluate the circling interface, we conducted an experiment with 16 participants, comparing the performance on pointing tasks with different combinations of selection method (circling interface, physical mouse and dwelling interface) and input device (normal computer mouse, head pointer and joystick mouse emulator). A circling interface is compatible with many types of pointing devices, not requiring physical activation of mouse buttons, and is more efficient than dwell-clicking. Across all common pointing operations, the circling interface had a tendency to produce faster performance with a head-mounted mouse emulator than with a joystick mouse. The performance accuracy of the circling interface outperformed the dwelling interface. It was demonstrated that the circling interface has the potential as another alternative pointing method for selecting and manipulating objects in a graphical user interface. Implications for Rehabilitation A circling interface will improve clinical practice by providing an alternative pointing method that does not require physically activating mouse buttons and is more efficient than dwell-clicking. The Circling interface can also work with AAC devices.

  3. Portable Dextrous Force Feedback Master for robot telemanipulation (PDMFF)

    NASA Technical Reports Server (NTRS)

    Burdea, Grigore C.; Speeter, Thomas H.

    1989-01-01

    A major drawback of open loop masters is a lack of force feedback, limiting their ability to perform complex tasks such as assembly and repair. Researchers present a simple dextrous force feedback master for computer assisted telemanipulation. The device is compact, portable and can be held in the operator hand, without the need for a special joystick or console. The system is capable of both position feed forward and force feedback, using electronic position sensors and a pneumatic micro-actuator. The level of forces exercised by the pneumatic actuator is such that near rigidity may be attained. Experimental results showing good system linearity and small time lag are given.

  4. Talking Wheelchair

    NASA Technical Reports Server (NTRS)

    1981-01-01

    Communication is made possible for disabled individuals by means of an electronic system, developed at Stanford University's School of Medicine, which produces highly intelligible synthesized speech. Familiarly known as the "talking wheelchair" and formally as the Versatile Portable Speech Prosthesis (VPSP). Wheelchair mounted system consists of a word processor, a video screen, a voice synthesizer and a computer program which instructs the synthesizer how to produce intelligible sounds in response to user commands. Computer's memory contains 925 words plus a number of common phrases and questions. Memory can also store several thousand other words of the user's choice. Message units are selected by operating a simple switch, joystick or keyboard. Completed message appears on the video screen, then user activates speech synthesizer, which generates a voice with a somewhat mechanical tone. With the keyboard, an experienced user can construct messages as rapidly as 30 words per minute.

  5. Intelligent Control Wheelchair Using a New Visual Joystick.

    PubMed

    Rabhi, Yassine; Mrabet, Makrem; Fnaiech, Farhat

    2018-01-01

    A new control system of a hand gesture-controlled wheelchair (EWC) is proposed. This smart control device is suitable for a large number of patients who cannot manipulate a standard joystick wheelchair. The movement control system uses a camera fixed on the wheelchair. The patient's hand movements are recognized using a visual recognition algorithm and artificial intelligence software; the derived corresponding signals are thus used to control the EWC in real time. One of the main features of this control technique is that it allows the patient to drive the wheelchair with a variable speed similar to that of a standard joystick. The designed device "hand gesture-controlled wheelchair" is performed at low cost and has been tested on real patients and exhibits good results. Before testing the proposed control device, we have created a three-dimensional environment simulator to test its performances with extreme security. These tests were performed on real patients with diverse hand pathologies in Mohamed Kassab National Institute of Orthopedics, Physical and Functional Rehabilitation Hospital of Tunis, and the validity of this intelligent control system had been proved.

  6. Intelligent Control Wheelchair Using a New Visual Joystick

    PubMed Central

    Mrabet, Makrem; Fnaiech, Farhat

    2018-01-01

    A new control system of a hand gesture-controlled wheelchair (EWC) is proposed. This smart control device is suitable for a large number of patients who cannot manipulate a standard joystick wheelchair. The movement control system uses a camera fixed on the wheelchair. The patient's hand movements are recognized using a visual recognition algorithm and artificial intelligence software; the derived corresponding signals are thus used to control the EWC in real time. One of the main features of this control technique is that it allows the patient to drive the wheelchair with a variable speed similar to that of a standard joystick. The designed device “hand gesture-controlled wheelchair” is performed at low cost and has been tested on real patients and exhibits good results. Before testing the proposed control device, we have created a three-dimensional environment simulator to test its performances with extreme security. These tests were performed on real patients with diverse hand pathologies in Mohamed Kassab National Institute of Orthopedics, Physical and Functional Rehabilitation Hospital of Tunis, and the validity of this intelligent control system had been proved. PMID:29599953

  7. Skills based evaluation of alternative input methods to command a semi-autonomous electric wheelchair.

    PubMed

    Rojas, Mario; Ponce, Pedro; Molina, Arturo

    2016-08-01

    This paper presents the evaluation, under standardized metrics, of alternative input methods to steer and maneuver a semi-autonomous electric wheelchair. The Human-Machine Interface (HMI), which includes a virtual joystick, head movements and speech recognition controls, was designed to facilitate mobility skills for severely disabled people. Thirteen tasks, which are common to all the wheelchair users, were attempted five times by controlling it with the virtual joystick and the hands-free interfaces in different areas for disabled and non-disabled people. Even though the prototype has an intelligent navigation control, based on fuzzy logic and ultrasonic sensors, the evaluation was done without assistance. The scored values showed that both controls, the head movements and the virtual joystick have similar capabilities, 92.3% and 100%, respectively. However, the 54.6% capacity score obtained for the speech control interface indicates the needs of the navigation assistance to accomplish some of the goals. Furthermore, the evaluation time indicates those skills which require more user's training with the interface and specifications to improve the total performance of the wheelchair.

  8. Roughness Perception of Haptically Displayed Fractal Surfaces

    NASA Technical Reports Server (NTRS)

    Costa, Michael A.; Cutkosky, Mark R.; Lau, Sonie (Technical Monitor)

    2000-01-01

    Surface profiles were generated by a fractal algorithm and haptically rendered on a force feedback joystick, Subjects were asked to use the joystick to explore pairs of surfaces and report to the experimenter which of the surfaces they felt was rougher. Surfaces were characterized by their root mean square (RMS) amplitude and their fractal dimension. The most important factor affecting the perceived roughness of the fractal surfaces was the RMS amplitude of the surface. When comparing surfaces of fractal dimension 1.2-1.35 it was found that the fractal dimension was negatively correlated with perceived roughness.

  9. Ordinal judgments of numerical symbols by macaques (Macaca mulatta)

    NASA Technical Reports Server (NTRS)

    Washburn, David A.; Rumbaugh, Duane M.

    1991-01-01

    Two rhesus monkeys (Macaca mulatta) learned that the arabic numerals 0 through 9 represented corresponding quantities of food pellets. By manipulating a joystick, the monkeys were able to make a selection of paired numerals presented on a computer screen. Although the monkeys received a corresponding number of pellets even if the lesser of the two numerals was selected, they learned generally to choose the numeral of greatest value even when pellet delivery was made arrhythmic. In subsequent tests, they chose the numerals of greater value when presented in novel combinations or in random arrays of up to five numerals. Thus, the monkeys made ordinal judgments of numerical symbols in accordance with their absolute or relative values.

  10. Automation of learning-set testing - The video-task paradigm

    NASA Technical Reports Server (NTRS)

    Washburn, David A.; Hopkins, William D.; Rumbaugh, Duane M.

    1989-01-01

    Researchers interested in studying discrimination learning in primates have typically utilized variations in the Wisconsin General Test Apparatus (WGTA). In the present experiment, a new testing apparatus for the study of primate learning is proposed. In the video-task paradigm, rhesus monkeys (Macaca mulatta) respond to computer-generated stimuli by manipulating a joystick. Using this apparatus, discrimination learning-set data for 2 monkeys were obtained. Performance on Trial 2 exceeded 80 percent within 200 discrimination learning problems. These data illustrate the utility of the video-task paradigm in comparative research. Additionally, the efficient learning and rich data that were characteristic of this study suggest several advantages of the present testing paradigm over traditional WGTA testing.

  11. The specificity of memory enhancement during interaction with a virtual environment.

    PubMed

    Brooks, B M; Attree, E A; Rose, F D; Clifford, B R; Leadbetter, A G

    1999-01-01

    Two experiments investigated differences between active and passive participation in a computer-generated virtual environment in terms of spatial memory, object memory, and object location memory. It was found that active participants, who controlled their movements in the virtual environment using a joystick, recalled the spatial layout of the virtual environment better than passive participants, who merely watched the active participants' progress. Conversely, there were no significant differences between the active and passive participants' recall or recognition of the virtual objects, nor in their recall of the correct locations of objects in the virtual environment. These findings are discussed in terms of subject-performed task research and the specificity of memory enhancement in virtual environments.

  12. Driving performance in a power wheelchair simulator.

    PubMed

    Archambault, Philippe S; Tremblay, Stéphanie; Cachecho, Sarah; Routhier, François; Boissy, Patrick

    2012-05-01

    A power wheelchair simulator can allow users to safely experience various driving tasks. For such training to be efficient, it is important that driving performance be equivalent to that in a real wheelchair. This study aimed at comparing driving performance in a real and in a simulated environment. Two groups of healthy young adults performed different driving tasks, either in a real power wheelchair or in a simulator. Smoothness of joystick control as well as the time necessary to complete each task were recorded and compared between the two groups. Driving strategies were analysed from video recordings. The sense of presence, of really being in the virtual environment, was assessed through a questionnaire. Smoothness of joystick control was the same in the real and virtual groups. Task completion time was higher in the simulator for the more difficult tasks. Both groups showed similar strategies and difficulties. The simulator generated a good sense of presence, which is important for motivation. Performance was very similar for power wheelchair driving in the simulator or in real life. Thus, the simulator could potentially be used to complement training of individuals who require a power wheelchair and use a regular joystick. [Box: see text].

  13. Investigation on sense of control parameters for joystick interface in remote operated container crane application

    NASA Astrophysics Data System (ADS)

    Abdullah, U. N. N.; Handroos, H.

    2017-09-01

    Introduction: This paper presents the study of sense of control parameters to improve the lack of direct motion feeling through remote operated container crane station (ROCCS) joystick interface. The investigations of the parameters in this study are important to develop the engineering parameters related to the sense of control goal in the next design process. Methodology: Structured interviews and observations were conducted to obtain the user experience data from thirteen remote container crane operators from two international terminals. Then, interview analysis, task analysis, activity analysis and time line analysis were conducted to compare and contrast the results from interviews and observations. Results: Four experience parameters were identified to support the sense of control goal in the later design improvement of the ROCC joystick interface. The significance of difficulties to control, unsynchronized movements, facilitate in control and decision making in unexpected situation as parameters to the sense of control goal were validated by' feedbacks from operators as well as analysis. Contribution: This study provides feedback directly from end users towards developing a sustainable control interface for ROCCS in specific and remote operated off-road vehicles in general.

  14. Implicit and Explicit Motivational Tendencies to Faces Varying in Trustworthiness and Dominance in Men

    PubMed Central

    Radke, Sina; Kalt, Theresa; Wagels, Lisa; Derntl, Birgit

    2018-01-01

    Motivational tendencies to happy and angry faces are well-established, e.g., in the form of aggression. Approach-avoidance reactions are not only elicited by emotional expressions, but also linked to the evaluation of stable, social characteristics of faces. Grounded in the two fundamental dimensions of face-based evaluations proposed by Oosterhof and Todorov (2008), the current study tested whether emotionally neutral faces varying in trustworthiness and dominance potentiate approach-avoidance in 50 healthy male participants. Given that evaluations of social traits are influenced by testosterone, we further tested for associations of approach-avoidance tendencies with endogenous and prenatal indicators of testosterone. Computer-generated faces signaling high and low trustworthiness and dominance were used to elicit motivational reactions in three approach-avoidance tasks, i.e., one implicit and one explicit joystick-based paradigm, and an additional rating task. When participants rated their behavioral tendencies, highly trustworthy faces evoked approach, and highly dominant faces evoked avoidance. This pattern, however, did not translate to faster initiation times of corresponding approach-avoidance movements. Instead, the joystick tasks revealed general effects, such as faster reactions to faces signaling high trustworthiness or high dominance. These findings partially support the framework of Oosterhof and Todorov (2008) in guiding approach-avoidance decisions, but not behavioral tendencies. Contrary to our expectations, neither endogenous nor prenatal indicators of testosterone were associated with motivational tendencies. Future studies should investigate the contexts in which testosterone influences social motivation. PMID:29410619

  15. Cumulative trauma disorder risk for children using computer products: results of a pilot investigation with a student convenience sample.

    PubMed

    Burke, Adam; Peper, Erik

    2002-01-01

    Cumulative trauma disorder is a major health problem for adults. Despite a growing understanding of adult cumulative trauma disorder, however, little is known about the risks for younger populations. This investigation examined issues related to child/adolescent computer product use and upper body physical discomfort. A convenience sample of 212 students, grades 1-12, was interviewed at their homes by a college-age sibling or relative. One of the child's parents was also interviewed. A 22-item questionnaire was used for data-gathering. Questionnaire items included frequency and duration of use, type of computer products/games and input devices used, presence of physical discomfort, and parental concerns related to the child's computer use. Many students experienced physical discomfort attributed to computer use, such as wrist pain (30%) and back pain (15%). Specific computer activities-such as using a joystick or playing noneducational games-were significantly predictive of physical discomfort using logistic multiple regression. Many parents reported difficulty getting their children off the computer (46%) and that their children spent less time outdoors (35%). Computer product use within this cohort was associated with self-reported physical discomfort. Results suggest a need for more extensive study, including multiyear longitudinal surveys.

  16. Comparison of three different techniques for camera and motion control of a teleoperated robot.

    PubMed

    Doisy, Guillaume; Ronen, Adi; Edan, Yael

    2017-01-01

    This research aims to evaluate new methods for robot motion control and camera orientation control through the operator's head orientation in robot teleoperation tasks. Specifically, the use of head-tracking in a non-invasive way, without immersive virtual reality devices was combined and compared with classical control modes for robot movements and camera control. Three control conditions were tested: 1) a condition with classical joystick control of both the movements of the robot and the robot camera, 2) a condition where the robot movements were controlled by a joystick and the robot camera was controlled by the user head orientation, and 3) a condition where the movements of the robot were controlled by hand gestures and the robot camera was controlled by the user head orientation. Performance, workload metrics and their evolution as the participants gained experience with the system were evaluated in a series of experiments: for each participant, the metrics were recorded during four successive similar trials. Results shows that the concept of robot camera control by user head orientation has the potential of improving the intuitiveness of robot teleoperation interfaces, specifically for novice users. However, more development is needed to reach a margin of progression comparable to a classical joystick interface. Copyright © 2016 Elsevier Ltd. All rights reserved.

  17. Control devices and steering strategies in pathway surgery.

    PubMed

    Fan, Chunman; Jelínek, Filip; Dodou, Dimitra; Breedveld, Paul

    2015-02-01

    For pathway surgery, that is, minimally invasive procedures carried out transluminally or through instrument-created pathways, handheld maneuverable instruments are being developed. As the accompanying control interfaces of such instruments have not been optimized for intuitive manipulation, we investigated the effect of control mode (1DoF or 2DoF), and control device (joystick or handgrip) on human performance in a navigation task. The experiments were conducted using the Endo-PaC (Endoscopic-Path Controller), a simulator that emulates the shaft and handle of a maneuverable instrument, combined with custom-developed software animating pathway surgical scenarios. Participants were asked to guide a virtual instrument without collisions toward a target located at the end of a virtual curved tunnel. The performance was assessed in terms of task completion time, path length traveled by the virtual instrument, motion smoothness, collision metrics, subjective workload, and personal preference. The results indicate that 2DoF control leads to faster task completion and fewer collisions with the tunnel wall combined with a strong subjective preference compared with 1DoF control. Handgrip control appeared to be more intuitive to master than joystick control. However, the participants experienced greater physical demand and had longer path lengths with handgrip than joystick control. Copyright © 2015 Elsevier Inc. All rights reserved.

  18. Directional control-response compatibility of joystick steered shuttle cars.

    PubMed

    Burgess-Limerick, Robin; Zupanc, Christine M; Wallis, Guy

    2012-01-01

    Shuttle cars are an unusual class of vehicle operated in underground coal mines, sometimes in close proximity to pedestrians and steering errors may have very serious consequences. A directional control-response incompatibility has previously been described in shuttle cars which are controlled using a steering wheel oriented perpendicular to the direction of travel. Some other shuttle car operators are seated perpendicular to the direction of travel and steer the car via a seat mounted joystick. A virtual simulation was utilised to determine whether the steering arrangement in these vehicles maintains directional control-response compatibility. Twenty-four participants were randomly assigned to either a condition corresponding to this design (consistent direction), or a condition in which the directional steering response was reversed while driving in-bye (visual field compatible). Significantly less accurate steering performance was exhibited by the consistent direction group during the in-bye trials only. Shuttle cars which provide the joystick steering mechanism described here require operators to accommodate alternating compatible and incompatible directional control-response relationships with each change of car direction. A virtual simulation of an underground coal shuttle car demonstrates that the design incorporates a directional control-response incompatibility when driving the vehicle in one direction. This design increases the probability of operator error, with potential adverse safety and productivity consequences.

  19. The design of mobile robot control system for the aged and the disabled

    NASA Astrophysics Data System (ADS)

    Qiang, Wang; Lei, Shi; Xiang, Gao; Jin, Zhang

    2017-01-01

    This paper designs a control system of mobile robot for the aged and the disabled, which consists of two main parts: human-computer interaction and drive control module. The data of the two parts is transferred via universal asynchronous receiver/transmitter. In the former part, the speed and direction information of the mobile robot is obtained by hall joystick. In the latter part, the electronic differential algorithm is developed to implement the robot mobile function by driving two-wheel motors. In order to improve the comfort of the robot when speed or direction is changed, the least squares algorithm is used to optimize the speed characteristic curves of the two motors. Experimental results have verified the effectiveness of the designed system.

  20. The heuristic and motivational value of video reinforcement

    NASA Technical Reports Server (NTRS)

    Washburn, D. A.; Gulledge, J. P.; Rumbaugh, D. M.

    1997-01-01

    Four rhesus monkeys (Macaca mulatta) were tested on joystick-based computer tasks in which they could choose to be reinforced either with pellets-only or with pellets + video. A variety of videotapes were used to reinforce task performance. The monkeys significantly preferred to be rewarded with a pellet and 10 s of a blank screen than a pellet plus 10 s of videotape. When they did choose to see videotaped images, however, they were significantly more likely to view video of themselves than video of their roommate or of unfamiliar conspecifics. These data support earlier findings of individual differences in preference for video reinforcement, and have clear implications for the study of face-recognition and self-recognition by nonhuman primates.

  1. Dynamic Neural Correlates of Motor Error Monitoring and Adaptation during Trial-to-Trial Learning

    PubMed Central

    Tan, Huiling; Jenkinson, Ned

    2014-01-01

    A basic EEG feature upon voluntary movements in healthy human subjects is a β (13–30 Hz) band desynchronization followed by a postmovement event-related synchronization (ERS) over contralateral sensorimotor cortex. The functional implications of these changes remain unclear. We hypothesized that, because β ERS follows movement, it may reflect the degree of error in that movement, and the salience of that error to the task at hand. As such, the signal might underpin trial-to-trial modifications of the internal model that informs future movements. To test this hypothesis, EEG was recorded in healthy subjects while they moved a joystick-controlled cursor to visual targets on a computer screen, with different rotational perturbations applied between the joystick and cursor. We observed consistently lower β ERS in trials with large error, even when other possible motor confounds, such as reaction time, movement duration, and path length, were controlled, regardless of whether the perturbation was random or constant. There was a negative trial-to-trial correlation between the size of the absolute initial angular error and the amplitude of the β ERS, and this negative correlation was enhanced when other contextual information about the behavioral salience of the angular error, namely, the bias and variance of errors in previous trials, was additionally considered. These same features also had an impact on the behavioral performance. The findings suggest that the β ERS reflects neural processes that evaluate motor error and do so in the context of the prior history of errors. PMID:24741058

  2. Human Subthalamic Nucleus in Movement Error Detection and Its Evaluation during Visuomotor Adaptation

    PubMed Central

    Zavala, Baltazar; Pogosyan, Alek; Ashkan, Keyoumars; Zrinzo, Ludvic; Foltynie, Thomas; Limousin, Patricia; Brown, Peter

    2014-01-01

    Monitoring and evaluating movement errors to guide subsequent movements is a critical feature of normal motor control. Previously, we showed that the postmovement increase in electroencephalographic (EEG) beta power over the sensorimotor cortex reflects neural processes that evaluate motor errors consistent with Bayesian inference (Tan et al., 2014). Whether such neural processes are limited to this cortical region or involve the basal ganglia is unclear. Here, we recorded EEG over the cortex and local field potential (LFP) activity in the subthalamic nucleus (STN) from electrodes implanted in patients with Parkinson's disease, while they moved a joystick-controlled cursor to visual targets displayed on a computer screen. After movement offsets, we found increased beta activity in both local STN LFP and sensorimotor cortical EEG and in the coupling between the two, which was affected by both error magnitude and its contextual saliency. The postmovement increase in the coupling between STN and cortex was dominated by information flow from sensorimotor cortex to STN. However, an information drive appeared from STN to sensorimotor cortex in the first phase of the adaptation, when a constant rotation was applied between joystick inputs and cursor outputs. The strength of the STN to cortex drive correlated with the degree of adaption achieved across subjects. These results suggest that oscillatory activity in the beta band may dynamically couple the sensorimotor cortex and basal ganglia after movements. In particular, beta activity driven from the STN to cortex indicates task-relevant movement errors, information that may be important in modifying subsequent motor responses. PMID:25505327

  3. Development of a Field-Deployable Psychomotor Vigilance Test to Monitor Helicopter Pilot Performance.

    PubMed

    McMahon, Terry W; Newman, David G

    2016-04-01

    Flying a helicopter is a complex psychomotor skill. Fatigue is a serious threat to operational safety, particularly for sustained helicopter operations involving high levels of cognitive information processing and sustained time on task. As part of ongoing research into this issue, the object of this study was to develop a field-deployable helicopter-specific psychomotor vigilance test (PVT) for the purpose of daily performance monitoring of pilots. The PVT consists of a laptop computer, a hand-operated joystick, and a set of rudder pedals. Screen-based compensatory tracking task software includes a tracking ball (operated by the joystick) which moves randomly in all directions, and a second tracking ball which moves horizontally (operated by the rudder pedals). The 5-min test requires the pilot to keep both tracking balls centered. This helicopter-specific PVT's portability and integrated data acquisition and storage system enables daily field monitoring of the performance of individual helicopter pilots. The inclusion of a simultaneous foot-operated tracking task ensures divided attention for helicopter pilots as the movement of both tracking balls requires simultaneous inputs. This PVT is quick, economical, easy to use, and specific to the operational flying task. It can be used for performance monitoring purposes, and as a general research tool for investigating the psychomotor demands of helicopter operations. While reliability and validity testing is warranted, data acquired from this test could help further our understanding of the effect of various factors (such as fatigue) on helicopter pilot performance, with the potential of contributing to helicopter operational safety.

  4. Momentary assessment of interpersonal process in psychotherapy.

    PubMed

    Thomas, Katherine M; Hopwood, Christopher J; Woody, Erik; Ethier, Nicole; Sadler, Pamela

    2014-01-01

    To demonstrate how a novel computer joystick coding method can illuminate the study of interpersonal processes in psychotherapy sessions, we applied it to Shostrom's (1966) well-known films in which a client, Gloria, had sessions with 3 prominent psychotherapists. The joystick method, which records interpersonal behavior as nearly continuous flows on the plane defined by the interpersonal dimensions of control and affiliation, provides an excellent sampling of variability in each person's interpersonal behavior across the session. More important, it yields extensive information about the temporal dynamics that interrelate clients' and therapists' behaviors. Gloria's 3 psychotherapy sessions were characterized using time-series statistical indices and graphical representations. Results demonstrated that patterns of within-person variability tended to be markedly asymmetric, with a predominant, set-point-like interpersonal style from which deviations mostly occurred in just 1 direction (e.g., occasional submissive departures from a modal dominant style). In addition, across each session, the therapist and client showed strongly cyclical variations in both control and affiliation, and these oscillations were entrained to different extents depending on the therapist. We interpreted different patterns of moment-to-moment complementarity of interpersonal behavior in terms of different therapeutic goals, such as fostering a positive alliance versus disconfirming the client's interpersonal expectations. We also showed how this method can be used to provide a more detailed analysis of specific shorter segments from each of the sessions. Finally, we compared our approach to alternative techniques, such as act-to-act lagged relations and dynamic systems and pointed to a variety of possible research and training applications. (PsycINFO Database Record (c) 2014 APA, all rights reserved).

  5. Efforts toward an autonomous wheelchair - biomed 2011.

    PubMed

    Barrett, Steven; Streeter, Robert

    2011-01-01

    An autonomous wheelchair is in development to provide mobility to those with significant physical challenges. The overall goal of the project is to develop a wheelchair that is fully autonomous with the ability to navigate about an environment and negotiate obstacles. As a starting point for the project, we have reversed engineered the joystick control system of an off-the-shelf commercially available wheelchair. The joystick control has been replaced with a microcontroller based system. The microcontroller has the capability to interface with a number of subsystems currently under development including wheel odometers, obstacle avoidance sensors, and ultrasonic-based wall sensors. This paper will discuss the microcontroller based system and provide a detailed system description. Results of this study may be adapted to commercial or military robot control.

  6. PandaEPL: a library for programming spatial navigation experiments.

    PubMed

    Solway, Alec; Miller, Jonathan F; Kahana, Michael J

    2013-12-01

    Recent advances in neuroimaging and neural recording techniques have enabled researchers to make significant progress in understanding the neural mechanisms underlying human spatial navigation. Because these techniques generally require participants to remain stationary, computer-generated virtual environments are used. We introduce PandaEPL, a programming library for the Python language designed to simplify the creation of computer-controlled spatial-navigation experiments. PandaEPL is built on top of Panda3D, a modern open-source game engine. It allows users to construct three-dimensional environments that participants can navigate from a first-person perspective. Sound playback and recording and also joystick support are provided through the use of additional optional libraries. PandaEPL also handles many tasks common to all cognitive experiments, including managing configuration files, logging all internal and participant-generated events, and keeping track of the experiment state. We describe how PandaEPL compares with other software for building spatial-navigation experiments and walk the reader through the process of creating a fully functional experiment.

  7. PandaEPL: A library for programming spatial navigation experiments

    PubMed Central

    Solway, Alec; Miller, Jonathan F.

    2013-01-01

    Recent advances in neuroimaging and neural recording techniques have enabled researchers to make significant progress in understanding the neural mechanisms underlying human spatial navigation. Because these techniques generally require participants to remain stationary, computer-generated virtual environments are used. We introduce PandaEPL, a programming library for the Python language designed to simplify the creation of computer-controlled spatial-navigation experiments. PandaEPL is built on top of Panda3D, a modern open-source game engine. It allows users to construct three-dimensional environments that participants can navigate from a first-person perspective. Sound playback and recording and also joystick support are provided through the use of additional optional libraries. PandaEPL also handles many tasks common to all cognitive experiments, including managing configuration files, logging all internal and participant-generated events, and keeping track of the experiment state. We describe how PandaEPL compares with other software for building spatial-navigation experiments and walk the reader through the process of creating a fully functional experiment. PMID:23549683

  8. Evaluation of a modified Fitts law brain-computer interface target acquisition task in able and motor disabled individuals

    NASA Astrophysics Data System (ADS)

    Felton, E. A.; Radwin, R. G.; Wilson, J. A.; Williams, J. C.

    2009-10-01

    A brain-computer interface (BCI) is a communication system that takes recorded brain signals and translates them into real-time actions, in this case movement of a cursor on a computer screen. This work applied Fitts' law to the evaluation of performance on a target acquisition task during sensorimotor rhythm-based BCI training. Fitts' law, which has been used as a predictor of movement time in studies of human movement, was used here to determine the information transfer rate, which was based on target acquisition time and target difficulty. The information transfer rate was used to make comparisons between control modalities and subject groups on the same task. Data were analyzed from eight able-bodied and five motor disabled participants who wore an electrode cap that recorded and translated their electroencephalogram (EEG) signals into computer cursor movements. Direct comparisons were made between able-bodied and disabled subjects, and between EEG and joystick cursor control in able-bodied subjects. Fitts' law aptly described the relationship between movement time and index of difficulty for each task movement direction when evaluated separately and averaged together. This study showed that Fitts' law can be successfully applied to computer cursor movement controlled by neural signals.

  9. Partial camera automation in an unmanned air vehicle.

    PubMed

    Korteling, J E; van der Borg, W

    1997-03-01

    The present study focused on an intelligent, semiautonomous, interface for a camera operator of a simulated unmanned air vehicle (UAV). This interface used system "knowledge" concerning UAV motion in order to assist a camera operator in tracking an object moving through the landscape below. The semiautomated system compensated for the translations of the UAV relative to the earth. This compensation was accompanied by the appropriate joystick movements ensuring tactile (haptic) feedback of these system interventions. The operator had to superimpose self-initiated joystick manipulations over these system-initiated joystick motions in order to track the motion of a target (a driving truck) relative to the terrain. Tracking data showed that subjects performed substantially better with the active system. Apparently, the subjects had no difficulty in maintaining control, i.e., "following" the active stick while superimposing self-initiated control movements over the system-interventions. Furthermore, tracking performance with an active interface was clearly superior relative to the passive system. The magnitude of this effect was equal to the effect of update-frequency (2-5 Hz) of the monitor image. The benefits of update frequency enhancement and semiautomated tracking were the greatest under difficult steering conditions. Mental workload scores indicated that, for the difficult tracking-dynamics condition, both semiautomation and update frequency increase resulted in less experienced mental effort. For the easier dynamics this effect was only seen for update frequency.

  10. "Yummy" versus "Yucky"! Explicit and implicit approach-avoidance motivations towards appealing and disgusting foods.

    PubMed

    Piqueras-Fiszman, Betina; Kraus, Alexandra A; Spence, Charles

    2014-07-01

    Wanting and rejecting food are natural reactions that we humans all experience, often unconsciously, on a daily basis. However, in the food domain, the focus to date has primarily been on the approach tendency, and researchers have tended not to study the two opposing tendencies in a balanced manner. Here, we develop a methodology with which to understand people's implicit and explicit reactions to both positive (appealing) and negative (disgusting) foods. It consists of a combination of direct and indirect computer-based tasks, as well as a validated food image stimulus set, specifically designed to investigate motivational approach and avoidance responses towards foods. Fifty non-dieting participants varying in terms of their hunger state (hungry vs. not hungry) reported their explicit evaluations of pleasantness, wanting, and disgust towards the idea of tasting each of the food images that were shown. Their motivational tendencies towards those food items were assessed indirectly using a joystick-based approach-avoidance procedure. For each of the food images that were presented, the participants had to move the joystick either towards or away from themselves (approach and avoidance movements, respectively) according to some unrelated instructions, while their reaction times were recorded. Our findings demonstrated the hypothesised approach-avoidance compatibility effect: a significant interaction of food valence and direction of movement. Furthermore, differences between the experimental groups were observed. The participants in the no-hunger group performed avoidance (vs. approach) movements significantly faster; and their approach movements towards positive (vs. negative) foods were significantly faster. As expected, the self-report measures revealed a strong effect of the food category on the three dependent variables and a strong main effect of the hunger state on wanting and to a lesser extent on pleasantness. Copyright © 2014 Elsevier Ltd. All rights reserved.

  11. Affective Synchrony in Dual- and Single-Smoker Couples: Further Evidence of “Symptom-System Fit”?

    PubMed Central

    ROHRBAUGH, MICHAEL J.; SHOHAM, VARDA; BUTLER, EMILYA.; HASLER, BRANT P.; BERMAN, JEFFREY S.

    2009-01-01

    Couples in which one or both partners smoked despite one of them having a heart or lung problem discussed a health-related disagreement before and during a period of laboratory smoking. Immediately afterwards, the partners in these 25 couples used independent joysticks to recall their continuous emotional experience during the interaction while watching themselves on video. A couple-level index of affective synchrony, reflecting correlated moment-to-moment change in the two partners’ joystick ratings, tended to increase from baseline to smoking for 9 dual-smoker couples but decrease for 16 single-smoker couples. Results suggest that coregulation of shared emotional experience could be a factor in smoking persistence, particularly when both partners in a couple smoke. Relationship-focused interventions addressing this fit between symptom and system may help smokers achieve stable cessation. PMID:19378645

  12. Direction of balance and perception of the upright are perceptually dissociable

    PubMed Central

    Panic, Alexander Sacha; DiZio, Paul; Lackner, James R.

    2015-01-01

    We examined whether the direction of balance rather than an otolith reference determines the perceived upright. Participants seated in a device that rotated around the roll axis used a joystick to control its motion. The direction of balance of the device, the location where it would not be accelerated to either side, could be offset from the gravitational vertical, a technique introduced by Riccio, Martin, and Stoffregen (J Exp Psychol Hum Percept Perform 18: 624–644, 1992). Participants used the joystick to align themselves in different trials with the gravitational vertical, the direction of balance, the upright, or the direction that minimized oscillations. They pressed the joystick trigger whenever they thought they were at the instructed orientation. Achieved angles for the “align with gravity” and “align with the upright” conditions were not different from each other and were significantly displaced past the gravitational vertical opposite from the direction of balance. Mean indicated angles for align with gravity and align with the upright coincided with the gravitational vertical. Both mean achieved and indicated angles for the “minimize oscillations” and “align with the direction of balance” conditions were significantly deviated toward the gravitational vertical. Three control experiments requiring self-settings to instructed orientations only, perceptual judgments only, and perceptual judgments during passive exposure to dynamic roll profiles confirmed that perception of the upright is determined by gravity, not by the direction of balance. PMID:25761954

  13. A user's guide for DTIZE an interactive digitizing and graphical editing computer program

    NASA Technical Reports Server (NTRS)

    Thomas, C. C.

    1981-01-01

    A guide for DTIZE, a two dimensional digitizing program with graphical editing capability, is presented. DTIZE provides the capability to simultaneously create and display a picture on the display screen. Data descriptions may be permanently saved in three different formats. DTIZE creates the picture graphics in the locator mode, thus inputting one coordinate each time the terminator button is pushed. Graphic input devices (GIN) are also used to select function command menu. These menu commands and the program's interactive prompting sequences provide a complete capability for creating, editing, and permanently recording a graphical picture file. DTIZE is written in FORTRAN IV language for the Tektronix 4081 graphic system utilizing the Plot 80 Distributed Graphics Library (DGL) subroutines. The Tektronix 4953/3954 Graphic Tablet with mouse, pen, or joystick are used as graphics input devices to create picture graphics.

  14. Design of an autonomous lunar construction utility vehicle

    NASA Technical Reports Server (NTRS)

    1990-01-01

    In order to prepare a site for a lunar base, an autonomously operated construction vehicle is necessary. Discussed here is a Lunar Construction Utility Vehicle (LCUV), which uses interchangeable construction implements. Design of an elastic loop track system has advanced to the testing stage. A standard coupling device has been designed to insure a proper connection between the different construction tools and the LCUV. Autonomous control of the track drive motors was simulated successfully through the use of a joystick and a computer interface. A study of hydrogen-oxygen fuel cells produced estimates of reactant and product requirements and identified multilayer insulation needs. Research on the 100-kW heat rejection system determined that it is necessary to transport the radiator panel on a utility trailer. Extensive logistical support for the 720 hour use cycle requires further study.

  15. Simulation of Physical Experiments in Immersive Virtual Environments

    NASA Technical Reports Server (NTRS)

    Noor, Ahmed K.; Wasfy, Tamer M.

    2001-01-01

    An object-oriented event-driven immersive Virtual environment is described for the creation of virtual labs (VLs) for simulating physical experiments. Discussion focuses on a number of aspects of the VLs, including interface devices, software objects, and various applications. The VLs interface with output devices, including immersive stereoscopic screed(s) and stereo speakers; and a variety of input devices, including body tracking (head and hands), haptic gloves, wand, joystick, mouse, microphone, and keyboard. The VL incorporates the following types of primitive software objects: interface objects, support objects, geometric entities, and finite elements. Each object encapsulates a set of properties, methods, and events that define its behavior, appearance, and functions. A container object allows grouping of several objects. Applications of the VLs include viewing the results of the physical experiment, viewing a computer simulation of the physical experiment, simulation of the experiments procedure, computational steering, and remote control of the physical experiment. In addition, the VL can be used as a risk-free (safe) environment for training. The implementation of virtual structures testing machines, virtual wind tunnels, and a virtual acoustic testing facility is described.

  16. Autonomous assistance navigation for robotic wheelchairs in confined spaces.

    PubMed

    Cheein, Fernando Auat; Carelli, Ricardo; De la Cruz, Celso; Muller, Sandra; Bastos Filho, Teodiano F

    2010-01-01

    In this work, a visual interface for the assistance of a robotic wheelchair's navigation is presented. The visual interface is developed for the navigation in confined spaces such as narrows corridors or corridor-ends. The interface performs two navigation modus: non-autonomous and autonomous. The non-autonomous driving of the robotic wheelchair is made by means of a hand-joystick. The joystick directs the motion of the vehicle within the environment. The autonomous driving is performed when the user of the wheelchair has to turn (90, 90 or 180 degrees) within the environment. The turning strategy is performed by a maneuverability algorithm compatible with the kinematics of the wheelchair and by the SLAM (Simultaneous Localization and Mapping) algorithm. The SLAM algorithm provides the interface with the information concerning the environment disposition and the pose -position and orientation-of the wheelchair within the environment. Experimental and statistical results of the interface are also shown in this work.

  17. Development of non-keyboard input device checklists through assessments.

    PubMed

    Woods, Valerie; Hastings, Sarah; Buckle, Peter; Haslam, Roger

    2003-11-01

    An assessment of non-keyboard input devices (NKID) was conducted to identify factors for good design in relation to operation, performance and comfort. Twenty-seven NKID users, working in health and safety, evaluated eight devices that included mice, trackballs and a joystick mouse. The factors considered important for good design were: (1) comfortable hand and finger position, (2) adequate control, (3) intuitive and easy to use, (4) ease of device, button and trackball movement, (5) good interaction with software, (6) provision of suitable accessories. Mice were rated more favourably than trackballs or the joystick mouse. The design of the standard 2-button mouse (D4) was considered most desirable to use; the 3-button mouse (D1) and 3-button curved mouse (D8) were also favoured. Assessment data and comments were drawn together with previously published research to produce useful tools for NKID purchasing (i.e. Device Purchasing Checklist) and assessment (i.e. Device Assessment Checklist).

  18. A graphics-oriented personal computer-based microscope charting system for neuroanatomical and neurochemical studies.

    PubMed

    Tourtellotte, W G; Lawrence, D T; Getting, P A; Van Hoesen, G W

    1989-07-01

    This report describes a computerized microscope charting system based on the IBM personal computer or compatible. Stepping motors are used to control the movement of the microscope stage and to encode its position by hand manipulation of a joystick. Tissue section contours and the location of cells labeled with various compounds are stored by the computer, plotted at any magnification and manipulated into composites created from several charted sections. The system has many advantages: (1) it is based on an industry standardized computer that is affordable and familiar; (2) compact and commercially available stepping motor microprocessors control the stage movement. These controllers increase reliability, simplify implementation, and increase efficiency by relieving the computer of time consuming control tasks; (3) the system has an interactive graphics interface allowing the operator to view the image during data collection. Regions of the graphics display can be enlarged during the charting process to provide higher resolution and increased accuracy; (4) finally, the digitized data are stored at 0.5 micron resolution and can be routed directly to a multi-pen plotter or exported to a computer-aided design (CAD) program to generate a publication-quality montage composed of several computerized chartings. The system provides a useful tool for the acquisition and qualitative analysis of data representing stained cells or chemical markers in tissue. The modular design, together with data storage at high resolution, allows for potential analytical enhancements involving planimetric, stereologic and 3-D serial section reconstruction.

  19. Wireless sEMG-Based Body-Machine Interface for Assistive Technology Devices.

    PubMed

    Fall, Cheikh Latyr; Gagnon-Turcotte, Gabriel; Dube, Jean-Francois; Gagne, Jean Simon; Delisle, Yanick; Campeau-Lecours, Alexandre; Gosselin, Clement; Gosselin, Benoit

    2017-07-01

    Assistive technology (AT) tools and appliances are being more and more widely used and developed worldwide to improve the autonomy of people living with disabilities and ease the interaction with their environment. This paper describes an intuitive and wireless surface electromyography (sEMG) based body-machine interface for AT tools. Spinal cord injuries at C5-C8 levels affect patients' arms, forearms, hands, and fingers control. Thus, using classical AT control interfaces (keypads, joysticks, etc.) is often difficult or impossible. The proposed system reads the AT users' residual functional capacities through their sEMG activity, and converts them into appropriate commands using a threshold-based control algorithm. It has proven to be suitable as a control alternative for assistive devices and has been tested with the JACO arm, an articulated assistive device of which the vocation is to help people living with upper-body disabilities in their daily life activities. The wireless prototype, the architecture of which is based on a 3-channel sEMG measurement system and a 915-MHz wireless transceiver built around a low-power microcontroller, uses low-cost off-the-shelf commercial components. The embedded controller is compared with JACO's regular joystick-based interface, using combinations of forearm, pectoral, masseter, and trapeze muscles. The measured index of performance values is 0.88, 0.51, and 0.41 bits/s, respectively, for correlation coefficients with the Fitt's model of 0.75, 0.85, and 0.67. These results demonstrate that the proposed controller offers an attractive alternative to conventional interfaces, such as joystick devices, for upper-body disabled people using ATs such as JACO.

  20. Video-task assessment of learning and memory in Macaques (Macaca mulatta) - Effects of stimulus movement on performance

    NASA Technical Reports Server (NTRS)

    Washburn, David A.; Hopkins, William D.; Rumbaugh, Duane M.

    1989-01-01

    Effects of stimulus movement on learning, transfer, matching, and short-term memory performance were assessed with 2 monkeys using a video-task paradigm in which the animals responded to computer-generated images by manipulating a joystick. Performance on tests of learning set, transfer index, matching to sample, and delayed matching to sample in the video-task paradigm was comparable to that obtained in previous investigations using the Wisconsin General Testing Apparatus. Additionally, learning, transfer, and matching were reliably and significantly better when the stimuli or discriminanda moved than when the stimuli were stationary. External manipulations such as stimulus movement may increase attention to the demands of a task, which in turn should increase the efficiency of learning. These findings have implications for the investigation of learning in other populations, as well as for the application of the video-task paradigm to comparative study.

  1. Effects of competition on video-task performance in monkeys (Macaca mulatta)

    NASA Technical Reports Server (NTRS)

    Washburn, David A.; Hopkins, William D.; Rumbaugh, Duane M.

    1990-01-01

    The effects of competition on performance of a video-formatted task were examined in a series of experiments. Two rhesus monkeys (Macaca mulatta) were trained to manipulate a joystick to shoot at moving targets on a computer screen. The task was made competitive by requiring both animals to shoot at the same target and by rewarding only the animal that hit the target first each trial. The competitive task produced a significant and robust speed-accuracy trade-off in performance. The monkeys hit the target in significantly less time on contested than on uncontested trials. However, they required significantly more shots to hit the target on contested trials in relation to uncontested trials. This effect was unchanged when various schedules of reinforcement were introduced in the uncontested trials. This supports the influence of competition qua competition on performance, a point further bolstered by other findings of behavioral contrast presented here.

  2. Effects of Long-Duration Microgravity on Fine Motor Skills: ISS One-Year Mission

    NASA Technical Reports Server (NTRS)

    Holden, Kritina; Greene, Maya; Cross, Ernest

    2017-01-01

    Fine motor skills will be critical in future long-duration missions, particularly those skills needed to interact with advanced technologies in next-generation vehicles, spacesuits, and habitats. Studies to date on the effects of microgravity and gravitational transitions on fine motor performance have not yielded conclusive results. Datasets are incomplete-timeline gaps in the microgravity data sessions. Studies have not focused on the fine motor actions that are likely to be required for interacting with software displays and controls (pointing, clicking, dragging, multi-touch/pinching). The majority of studies have used a joystick or arm reaching task. Touchscreen tablets are already in use on ISS, and at least one commercial partner is already planning a cockpit with touchscreens as the primary means of input. We must ensure that crewmembers are ready to perform with computer-based devices after a long-duration voyage and transition to surface operations.

  3. Design of an autonomous Lunar construction utility vehicle

    NASA Technical Reports Server (NTRS)

    Ash, Robert L.; Chew, Mason; Dixon, Iain (Editor)

    1990-01-01

    In order to prepare a site for a manned lunar base, an autonomously operated construction vehicle is necessary. A Lunar Construction Utility Vehicle (LCUV), which utilizes interchangeable construction implements, was designed conceptually. Some elements of the machine were studied in greater detail. Design of an elastic loop track system has advanced to the testing stage. A standard coupling device was designed to insure a proper connection between the different construction tools and the LCUV. Autonomous control of the track drive motors was simulated successfully through the use of a joystick and computer interface. A study of hydrogen-oxygen fuel cells has produced estimates of reactant and product size requirements and identified multi-layer insulation techniques. Research on a 100 kW heat rejection system has determined that it is necessary to house a radiator panel on a utility trailer. The impact of a 720 hr use cycle has produced a very large logistical support lien which requires further study.

  4. Video-task acquisition in rhesus monkeys (Macaca mulatta) and chimpanzees (Pan troglodytes): a comparative analysis

    NASA Technical Reports Server (NTRS)

    Hopkins, W. D.; Washburn, D. A.; Hyatt, C. W.; Rumbaugh, D. M. (Principal Investigator)

    1996-01-01

    This study describes video-task acquisition in two nonhuman primate species. The subjects were seven rhesus monkeys (Macaca mulatta) and seven chimpanzees (Pan troglodytes). All subjects were trained to manipulate a joystick which controlled a cursor displayed on a computer monitor. Two criterion levels were used: one based on conceptual knowledge of the task and one based on motor performance. Chimpanzees and rhesus monkeys attained criterion in a comparable number of trials using a conceptually based criterion. However, using a criterion based on motor performance, chimpanzees reached criterion significantly faster than rhesus monkeys. Analysis of error patterns and latency indicated that the rhesus monkeys had a larger asymmetry in response bias and were significantly slower in responding than the chimpanzees. The results are discussed in terms of the relation between object manipulation skills and video-task acquisition.

  5. Advanced display object selection methods for enhancing user-computer productivity

    NASA Technical Reports Server (NTRS)

    Osga, Glenn A.

    1993-01-01

    The User-Interface Technology Branch at NCCOSC RDT&E Division has been conducting a series of studies to address the suitability of commercial off-the-shelf (COTS) graphic user-interface (GUI) methods for efficiency and performance in critical naval combat systems. This paper presents an advanced selection algorithm and method developed to increase user performance when making selections on tactical displays. The method has also been applied with considerable success to a variety of cursor and pointing tasks. Typical GUI's allow user selection by: (1) moving a cursor with a pointing device such as a mouse, trackball, joystick, touchscreen; and (2) placing the cursor on the object. Examples of GUI objects are the buttons, icons, folders, scroll bars, etc. used in many personal computer and workstation applications. This paper presents an improved method of selection and the theoretical basis for the significant performance gains achieved with various input devices tested. The method is applicable to all GUI styles and display sizes, and is particularly useful for selections on small screens such as notebook computers. Considering the amount of work-hours spent pointing and clicking across all styles of available graphic user-interfaces, the cost/benefit in applying this method to graphic user-interfaces is substantial, with the potential for increasing productivity across thousands of users and applications.

  6. A brain computer interface using electrocorticographic signals in humans

    NASA Astrophysics Data System (ADS)

    Leuthardt, Eric C.; Schalk, Gerwin; Wolpaw, Jonathan R.; Ojemann, Jeffrey G.; Moran, Daniel W.

    2004-06-01

    Brain-computer interfaces (BCIs) enable users to control devices with electroencephalographic (EEG) activity from the scalp or with single-neuron activity from within the brain. Both methods have disadvantages: EEG has limited resolution and requires extensive training, while single-neuron recording entails significant clinical risks and has limited stability. We demonstrate here for the first time that electrocorticographic (ECoG) activity recorded from the surface of the brain can enable users to control a one-dimensional computer cursor rapidly and accurately. We first identified ECoG signals that were associated with different types of motor and speech imagery. Over brief training periods of 3-24 min, four patients then used these signals to master closed-loop control and to achieve success rates of 74-100% in a one-dimensional binary task. In additional open-loop experiments, we found that ECoG signals at frequencies up to 180 Hz encoded substantial information about the direction of two-dimensional joystick movements. Our results suggest that an ECoG-based BCI could provide for people with severe motor disabilities a non-muscular communication and control option that is more powerful than EEG-based BCIs and is potentially more stable and less traumatic than BCIs that use electrodes penetrating the brain. The authors declare that they have no competing financial interests.

  7. MARTI: man-machine animation real-time interface

    NASA Astrophysics Data System (ADS)

    Jones, Christian M.; Dlay, Satnam S.

    1997-05-01

    The research introduces MARTI (man-machine animation real-time interface) for the realization of natural human-machine interfacing. The system uses simple vocal sound-tracks of human speakers to provide lip synchronization of computer graphical facial models. We present novel research in a number of engineering disciplines, which include speech recognition, facial modeling, and computer animation. This interdisciplinary research utilizes the latest, hybrid connectionist/hidden Markov model, speech recognition system to provide very accurate phone recognition and timing for speaker independent continuous speech, and expands on knowledge from the animation industry in the development of accurate facial models and automated animation. The research has many real-world applications which include the provision of a highly accurate and 'natural' man-machine interface to assist user interactions with computer systems and communication with one other using human idiosyncrasies; a complete special effects and animation toolbox providing automatic lip synchronization without the normal constraints of head-sets, joysticks, and skilled animators; compression of video data to well below standard telecommunication channel bandwidth for video communications and multi-media systems; assisting speech training and aids for the handicapped; and facilitating player interaction for 'video gaming' and 'virtual worlds.' MARTI has introduced a new level of realism to man-machine interfacing and special effect animation which has been previously unseen.

  8. NASA biomedical Applications Team Advisory Center for Medical Technology and Systems

    NASA Technical Reports Server (NTRS)

    Siedband, M. P.

    1981-01-01

    Projects carried out by the UW-BATeam are reported. The following subjects were investigated: clinical opthalmic ultrasound improvements, magnetic cell sorters, hyperthermia treatment for cancer, joystick driving control for the handicapped, qualitative coronary artery imaging (MIPS), and speech autocuers.

  9. An fMRI study of joint action–varying levels of cooperation correlates with activity in control networks

    PubMed Central

    Chaminade, Thierry; Marchant, Jennifer L.; Kilner, James; Frith, Christopher D.

    2012-01-01

    As social agents, humans continually interact with the people around them. Here, motor cooperation was investigated using a paradigm in which pairs of participants, one being scanned with fMRI, jointly controlled a visually presented object with joystick movements. The object oscillated dynamically along two dimensions, color and width of gratings, corresponding to the two cardinal directions of joystick movements. While the overall control of each participant on the object was kept constant, the amount of cooperation along the two dimensions varied along four levels, from no (each participant controlled one dimension exclusively) to full (each participant controlled half of each dimension) cooperation. Increasing cooperation correlated with BOLD signal in the left parietal operculum and anterior cingulate cortex (ACC), while decreasing cooperation correlated with activity in the right inferior frontal and superior temporal gyri, the intraparietal sulci and inferior temporal gyri bilaterally, and the dorsomedial prefrontal cortex. As joint performance improved with the level of cooperation, we assessed the brain responses correlating with behavior, and found that activity in most of the areas associated with levels of cooperation also correlated with the joint performance. The only brain area found exclusively in the negative correlation with cooperation was in the dorso medial frontal cortex, involved in monitoring action outcome. Given the cluster location and condition-related signal change, we propose that this region monitored actions to extract the level of cooperation in order to optimize the joint response. Our results, therefore, indicate that, in the current experimental paradigm involving joint control of a visually presented object with joystick movements, the level of cooperation affected brain networks involved in action control, but not mentalizing. PMID:22715326

  10. Telerobotics: A simulation facility for university research

    NASA Technical Reports Server (NTRS)

    Stark, L.; Kim, W.; Tendick, F.; Tyler, M.; Hannaford, B.; Barakat, W.; Bergengruen, O.; Braddi, L.; Eisenberg, J.; Ellis, S.

    1987-01-01

    An experimental telerobotics (TR) simulation suitable for studying human operator (H.O.) performance is described. Simple manipulator pick-and-place and tracking tasks allowed quantitative comparison of a number of calligraphic display viewing conditions. A number of control modes could be compared in this TR simulation, including displacement, rate and acceleratory control using position and force joysticks. A homeomorphic controller turned out to be no better than joysticks; the adaptive properties of the H.O. can apparently permit quite good control over a variety of controller configurations and control modes. Training by optimal control example seemed helpful in preliminary experiments. An introduced communication delay was found to produce decrease in performance. In considerable part, this difficulty could be compensated for by preview control information. That neurological control of normal human movement contains a data period of 0.2 second may relate to this robustness of H.O. control to delay. The Ames-Berkeley enhanced perspective display was utilized in conjunction with an experimental helmet mounted display system (HMD) that provided stereoscopic enhanced views.

  11. Fuzzy Inference Based Obstacle Avoidance Control of Electric Powered Wheelchair Considering Driving Risk

    NASA Astrophysics Data System (ADS)

    Kiso, Atsushi; Murakami, Hiroki; Seki, Hirokazu

    This paper describes a novel obstacle avoidance control scheme of electric powered wheelchairs for realizing the safe driving in various environments. The “electric powered wheelchair” which generates the driving force by electric motors is expected to be widely used as a mobility support system for elderly people and disabled people; however, the driving performance must be further improved because the number of driving accidents caused by elderly operator's narrow sight and joystick operation errors is increasing. This paper proposes a novel obstacle avoidance control scheme based on fuzzy algorithm to prevent driving accidents. The proposed control system determines the driving direction by fuzzy algorithm based on the information of the joystick operation and distance to obstacles measured by ultrasonic sensors. Fuzzy rules to determine the driving direction are designed surely to avoid passers-by and walls considering the human's intent and driving environments. Some driving experiments on the practical situations show the effectiveness of the proposed control system.

  12. Moving Evidence into Practice: Cost Analysis and Assessment of Macaques’ Sustained Behavioral Engagement with Videogames and Foraging Devices

    PubMed Central

    Bennett, Allyson J.; Perkins, Chaney M.; Tenpas, Parker D.; Reinebach, Alma L.; Pierre, Peter J.

    2017-01-01

    Environmental enrichment plans for captive nonhuman primates often include provision of foraging devices. The rationale for using foraging devices is to promote species-typical activity patterns that encourage physical engagement and provide multi-sensory stimulation. However, these devices have been shown to be ineffective at sustaining manipulation over long periods of time, and often produce minimal cognitive engagement. Here we use an evidence-based approach to directly compare the amount of object-directed behavior with a foraging device and a computer-based videogame system. We recorded 11adult male rhesus monkeys’ interactions with a foraging device and two tasks within a joystick videogame cognitive test battery. Both techniques successfully produced high levels of engagement during the initial 20-min of observation. After 1-hr the monkeys manipulated the foraging device significantly less than the joystick, F(2,10)= 43.93, p < .0001. Subsequent testing showed that the monkeys engaged in videogame play for the majority of a 5-hr period, provided that they received a 94mg chow pellet upon successful completion of trials. Using a model approach we developed previously as a basis for standardized cost:benefit analysis to inform facility decisions, we calculated the comprehensive cost of incorporating a videogame system as an enrichment strategy. The videogame system has a higher initial cost compared to widely-used foraging devices however, the ongoing labor and supply costs are relatively low. Our findings add to two decades of empirical studies by a number of laboratories that have demonstrated the successful use of videogame-based systems to promote sustained non-social cognitive engagement for macaques. The broader significance of the work lies in the application of a systematic approach to compare and contrast enrichment strategies and encourage evidence-based decision making when choosing an enrichment strategy in a manner that promotes meaningful cognitive enrichment to the animals. PMID:27404766

  13. Moving evidence into practice: cost analysis and assessment of macaques' sustained behavioral engagement with videogames and foraging devices.

    PubMed

    Bennett, Allyson J; Perkins, Chaney M; Tenpas, Parker D; Reinebach, Alma L; Pierre, Peter J

    2016-12-01

    Environmental enrichment plans for captive nonhuman primates often include provision of foraging devices. The rationale for using foraging devices is to promote species-typical activity patterns that encourage physical engagement and provide multi-sensory stimulation. However, these devices have been shown to be ineffective at sustaining manipulation over long periods of time, and often produce minimal cognitive engagement. Here we use an evidence-based approach to directly compare the amount of object-directed behavior with a foraging device and a computer-based videogame system. We recorded 11 adult male rhesus monkeys' interactions with a foraging device and two tasks within a joystick videogame cognitive test battery. Both techniques successfully produced high levels of engagement during the initial 20 min of observation. After 1 hr the monkeys manipulated the foraging device significantly less than the joystick, F(2,10) = 43.93, P < 0.0001. Subsequent testing showed that the monkeys engaged in videogame play for the majority of a 5 hr period, provided that they received a 94 mg chow pellet upon successful completion of trials. Using a model approach, we developed previously as a basis for standardized cost:benefit analysis to inform facility decisions, we calculated the comprehensive cost of incorporating a videogame system as an enrichment strategy. The videogame system has a higher initial cost compared to widely-used foraging devices, however, the ongoing labor and supply costs are relatively low. Our findings add to two decades of empirical studies by a number of laboratories that have demonstrated the successful use of videogame-based systems to promote sustained non-social cognitive engagement for macaques. The broader significance of the work lies in the application of a systematic approach to compare and contrast enrichment strategies and encourage evidence-based decision making when choosing an enrichment strategy in a manner that promotes meaningful cognitive enrichment to the animals. © 2016 Wiley Periodicals, Inc.

  14. Clinical evaluation of wireless inductive tongue computer interface for control of computers and assistive devices.

    PubMed

    Lontis, Eugen R; Lund, Morten E; Christensen, Henrik V; Bentsen, Bo; Gaihede, Michael; Caltenco, Hector A; Andreasen Struijk, Lotte N S

    2010-01-01

    Typing performance of a full alphabet keyboard and a joystick type of mouse (with on-screen keyboard) provided by a wireless integrated tongue control system (TCS) has been investigated. The speed and accuracy have been measured in a form of a throughput defining the true correct words per minute [cwpm]. Training character sequences were typed in a dedicated interface that provided visual feedback of activated sensors, a map of the alphabet associated, and the task character. Testing sentences were typed in Word, with limited visual feedback, using non-predictive typing (map of characters in alphabetic order associated to sensors) and predictive typing (LetterWise) for TCS keyboard, and non-predictive typing for TCS mouse. Two subjects participated for four and three consecutive days, respectively, two sessions per day. Maximal throughput of 2.94, 2.46, and 2.06, 1.68 [cwpm] were obtained with TCS keyboard by subject 1 and 2 with predictive and non-predictive typing respectively. Maximal throughput of 2.09 and 1.71 [cwpm] was obtained with TCS mouse by subject 1 and 2, respectively. Same experimental protocol has been planned for a larger number of subjects.

  15. Adding tactile realism to a virtual reality laparoscopic surgical simulator with a cost-effective human interface device

    NASA Astrophysics Data System (ADS)

    Mack, Ian W.; Potts, Stephen; McMenemy, Karen R.; Ferguson, R. S.

    2006-02-01

    The laparoscopic technique for performing abdominal surgery requires a very high degree of skill in the medical practitioner. Much interest has been focused on using computer graphics to provide simulators for training surgeons. Unfortunately, these tend to be complex and have a very high cost, which limits availability and restricts the length of time over which individuals can practice their skills. With computer game technology able to provide the graphics required for a surgical simulator, the cost does not have to be high. However, graphics alone cannot serve as a training simulator. Human interface hardware, the equivalent of the force feedback joystick for a flight simulator game, is required to complete the system. This paper presents a design for a very low cost device to address this vital issue. The design encompasses: the mechanical construction, the electronic interfaces and the software protocols to mimic a laparoscopic surgical set-up. Thus the surgeon has the capability of practicing two-handed procedures with the possibility of force feedback. The force feedback and collision detection algorithms allow surgeons to practice realistic operating theatre procedures with a good degree of authenticity.

  16. 42 CFR 410.38 - Durable medical equipment: Scope and conditions.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... vehicle whose steering is operated by an electronic device or a joystick to control direction and turning) or a power-operated vehicle (a three or four-wheeled motorized scooter that is operated by a tiller..., physical examination, diagnostic tests, summary of findings, diagnoses, treatment plans and/or other...

  17. 42 CFR 410.38 - Durable medical equipment: Scope and conditions.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... vehicle whose steering is operated by an electronic device or a joystick to control direction and turning) or a power-operated vehicle (a three or four-wheeled motorized scooter that is operated by a tiller..., physical examination, diagnostic tests, summary of findings, diagnoses, treatment plans and/or other...

  18. 42 CFR 410.38 - Durable medical equipment: Scope and conditions.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... vehicle whose steering is operated by an electronic device or a joystick to control direction and turning) or a power-operated vehicle (a three or four-wheeled motorized scooter that is operated by a tiller..., physical examination, diagnostic tests, summary of findings, diagnoses, treatment plans and/or other...

  19. Performance effects of alcohol intoxication and hangover at ground level and at simulated altitude.

    DOT National Transportation Integrated Search

    1979-10-01

    Eight private pilots (four men, four women) were trained to perform on a two-dimensional tracking task (joystick control of a localizer/glideslope instrument) and a respond as quickly as possible to the onset of a red pinlight, appended to the tracki...

  20. Rhesus Monkeys (Macaca Mulatta) Maintain Learning Set Despite Second-Order Stimulus-Response Spatial Discontiguity

    ERIC Educational Resources Information Center

    Beran, Michael J.; Washburn, David A.; Rumbaugh, Duane M.

    2007-01-01

    In many discrimination-learning tests, spatial separation between stimuli and response loci disrupts performance in rhesus macaques. However, monkeys are unaffected by such stimulus-response spatial discontiguity when responses occur through joystick-based computerized movement of a cursor. To examine this discrepancy, five monkeys were tested on…

  1. Driving Interface Based on Tactile Sensors for Electric Wheelchairs or Trolleys

    PubMed Central

    Trujillo-León, Andrés; Vidal-Verdú, Fernando

    2014-01-01

    This paper introduces a novel device based on a tactile interface to replace the attendant joystick in electric wheelchairs. It can also be used in other vehicles such as shopping trolleys. Its use allows intuitive driving that requires little or no training, so its usability is high. This is achieved by a tactile sensor located on the handlebar of the chair or trolley and the processing of the information provided by it. When the user interacts with the handle of the chair or trolley, he or she exerts a pressure pattern that depends on the intention to accelerate, brake or turn to the left or right. The electronics within the device then perform the signal conditioning and processing of the information received, identifying the intention of the user on the basis of this pattern using an algorithm, and translating it into control signals for the control module of the wheelchair. These signals are equivalent to those provided by a joystick. This proposal aims to help disabled people and their attendees and prolong the personal autonomy in a context of aging populations. PMID:24518892

  2. The Design and Evaluation of a Large-Scale Real-Walking Locomotion Interface

    PubMed Central

    Peck, Tabitha C.; Fuchs, Henry; Whitton, Mary C.

    2014-01-01

    Redirected Free Exploration with Distractors (RFED) is a large-scale real-walking locomotion interface developed to enable people to walk freely in virtual environments that are larger than the tracked space in their facility. This paper describes the RFED system in detail and reports on a user study that evaluated RFED by comparing it to walking-in-place and joystick interfaces. The RFED system is composed of two major components, redirection and distractors. This paper discusses design challenges, implementation details, and lessons learned during the development of two working RFED systems. The evaluation study examined the effect of the locomotion interface on users’ cognitive performance on navigation and wayfinding measures. The results suggest that participants using RFED were significantly better at navigating and wayfinding through virtual mazes than participants using walking-in-place and joystick interfaces. Participants traveled shorter distances, made fewer wrong turns, pointed to hidden targets more accurately and more quickly, and were able to place and label targets on maps more accurately, and more accurately estimate the virtual environment size. PMID:22184262

  3. Conditions for Interference Versus Facilitation During Sequential Sensorimotor Adaptation

    NASA Technical Reports Server (NTRS)

    Bock, Otmar; Schneider, Stefan; Bloomberg, Jacob

    2001-01-01

    We investigated how sensorimotor adaptation acquired during one experimental session influenced the adaptation in a subsequent session. The subjects' task was to track a visual target using a joystick-controlled cursor, while the relationship between joystick and cursor position was manipulated to introduce a sensorimotor discordance. Each subject participated in two sessions, separated by a pause of 2 min to 1 month duration. We found that adaptation was achieved within minutes, and persisted in the memory for at least a month, with only a small decay (experiment A). When the discordances administered in the two sessions were in mutual conflict, we found evidence for task interference (experiment B). However, when the discordances were independent, we found facilitation rather than interference (experiment C); the latter finding could not be explained by the use of an "easier" discordance in the second session (experiment D). We conclude that interference is due to an incompatibility between task requirements, and not to a competition of tasks for short-term memory. We further conclude that the ability to adapt to a sensorimotor discordance.

  4. Differential transfer processes in incremental visuomotor adaptation.

    PubMed

    Seidler, Rachel D

    2005-01-01

    Visuomotor adaptive processes were examined by testing transfer of adaptation between similar conditions. Participants made manual aiming movements with a joystick to hit targets on a computer screen, with real-time feedback display of their movement. They adapted to three different rotations of the display in a sequential fashion, with a return to baseline display conditions between rotations. Adaptation was better when participants had prior adaptive experiences. When performance was assessed using direction error (calculated at the time of peak velocity) and initial endpoint error (error before any overt corrective actions), transfer was greater when the final rotation reflected an addition of previously experienced rotations (adaptation order 30 degrees rotation, 15 degrees, 45 degrees) than when it was a subtraction of previously experienced conditions (adaptation order 45 degrees rotation, 15 degrees, 30 degrees). Transfer was equal regardless of adaptation order when performance was assessed with final endpoint error (error following any discrete, corrective actions). These results imply the existence of multiple independent processes in visuomotor adaptation.

  5. Design of inductive sensors for tongue control system for computers and assistive devices.

    PubMed

    Lontis, Eugen R; Struijk, Lotte N S A

    2010-07-01

    The paper introduces a novel design of air-core inductive sensors in printed circuit board (PCB) technology for a tongue control system. The tongue control system provides a quadriplegic person with a keyboard and a joystick type of mouse for interaction with a computer or for control of an assistive device. Activation of inductive sensors was performed with a cylindrical, soft ferromagnetic material (activation unit). Comparative analysis of inductive sensors in PCB technology with existing hand-made inductive sensors was performed with respect to inductance, resistance, and sensitivity to activation when the activation unit was placed in the center of the sensor. Optimisation of the activation unit was performed in a finite element model. PCBs with air-core inductive sensors were manufactured in a 10 layers, 100 microm and 120 microm line width technology. These sensors provided quality signals that could drive the electronics of the hand-made sensors. Furthermore, changing the geometry of the sensors allowed generation of variable signals correlated with the 2D movement of the activation unit at the sensors' surface. PCB technology for inductive sensors allows flexibility in design, automation of production and ease of possible integration with supplying electronics. The basic switch function of the inductive sensor can be extended to two-dimensional movement detection for pointing devices.

  6. Compendium of Abstracts. Volume 2

    DTIC Science & Technology

    2010-08-01

    researched for various applications such as self - healing and fluid transport. One method of creating these vascular systems is through a process called...Daniel J. Dexterous robotic manipulators that rely on joystick type interfaces for teleoperation require considerable time and effort to master...and lack an intuitive basis for human- robot interaction. This hampers operator performance, increases cognitive workload, and limits overall

  7. Assessing Constraints on Soldier Cognitive and Perceptual Motor Performance During Vehicle Motion

    DTIC Science & Technology

    2008-05-01

    vehicle systems are biomechanical (Sirouspour & Salcudean, 2003; Sövényi & Gillespie, 2007), cognitive (Parasuraman & Riley, 1997), and psychomotor...vs. velocity), pedals for braking/acceleration Environmental constraints associated with the support surface (Seat): Damping, inclination...steering and secondarily, performance differences between a joystick and pedals for throttle and brake control. Eleven participants com- pleted three

  8. A Virtual Joy-Stick Study of Emotional Responses and Social Motivation in Children with Autism Spectrum Disorder

    ERIC Educational Resources Information Center

    Kim, Kwanguk; Rosenthal, M. Zachary; Gwaltney, Mary; Jarrold, William; Hatt, Naomi; McIntyre, Nancy; Swain, Lindsay; Solomon, Marjorie; Mundy, Peter

    2015-01-01

    A new virtual reality task was employed which uses preference for interpersonal distance to social stimuli to examine social motivation and emotion perception in children with Autism Spectrum Disorders. Nineteen high function children with higher functioning Autism Spectrum Disorder (HFASD) and 23 age, gender, and IQ matched children with typical…

  9. A Virtual Joy-Stick Study of Emotional Responses and Social Motivation in Children with Autism Spectrum Disorder

    ERIC Educational Resources Information Center

    Kim, Kwanguk; Rosenthal, Zachary; Gwaltney, Mary; Jarrold, William; Lerro, Lindsay; Mundy, Peter

    2015-01-01

    A new virtual reality task was employed which uses preference for interpersonal distance to social stimuli to examine social motivation and emotion perception in children with Autism Spectrum Disorders. Nineteen children with higher functioning Autism Spectrum Disorder (HFA SD) and 23 age, gender, and IQ matched children with typical development…

  10. Vehicle Controller

    NASA Technical Reports Server (NTRS)

    1985-01-01

    UNISTICK is an airplane-like joystick being developed by Johnson Engineering under NASA and VA sponsorship. It allows a driver to control a vehicle with one hand, and is based upon technology developed for the Apollo Lunar Landings of the 1970's. It allows severely handicapped drivers to operate an automobile or van easily. The system is expected to be in production by March 1986.

  11. Home based computer-assisted upper limb exercise for young children with cerebral palsy: a feasibility study investigating impact on motor control and functional outcome.

    PubMed

    Weightman, Andrew; Preston, Nick; Levesley, Martin; Holt, Raymond; Mon-Williams, Mark; Clarke, Mike; Cozens, Alastair J; Bhakta, Bipin

    2011-03-01

    We developed a home-based rehabilitation exercise system incorporating a powered joystick linked to a computer game, to enable children with arm paresis to participate in independent home exercise. We investigated the feasibility and impact of using the system in the home setting. Eighteen children with cerebral palsy (median age 7.5 years, age range 5-16 years) were recruited from local National Health Service and the exercise system was installed in their home for approximately 4 weeks. Baseline and post-intervention assessments were taken: Canadian Occupational Performance Measure (COPM); kinematic measurement of movement quality (indexed by duration and smoothness) measured using a motion tracking system when performing a standardized computer task. The system was used for a median time of 75 min (interquartile range (IQR) 17-271), equating to 606 outward and 734 inward movements. Pre-COPM, (median 4.2); post-COPM (median 6.0); obs=34; z=3.62, p<0.01). Kinematic analysis of pre- and post-intervention movements on the standardized task showed decreased duration and increased smoothness. Some improvements in self-reported function and quality of movement are observed. This pilot study suggests that the system could be used to augment home-based arm exercise in an engaging way for children with cerebral palsy, although a controlled clinical trial is required to establish clinical efficacy. The feasibility of this technology has been demonstrated.

  12. Miniature Two-Axis Joystick Controller

    NASA Technical Reports Server (NTRS)

    Hollow, R.

    1983-01-01

    Novel movable-button-actuated self-centering controller uses optoelectronics to produce X and Y signals for aircraft control. In addition to be extremely compact, device puts our voltages having high signal-to-noise ratio, especially at critical center position where in many controllers this ratio is poorest. Combination of new saddle-shaped button and positive centering gives "feel" and "breakout" met with pilot approval.

  13. Games for Traffic Education: An Experimental Study of a Game-Based Driving Simulator

    ERIC Educational Resources Information Center

    Backlund, Per; Engstrom, Henrik; Johannesson, Mikael; Lebram, Mikael

    2010-01-01

    In this article, the authors report on the construction and evaluation of a game-based driving simulator using a real car as a joystick. The simulator is constructed from off-the-shelf hardware and the simulation runs on open-source software. The feasibility of the simulator as a learning tool has been experimentally evaluated. Results are…

  14. Haptic Paddle Enhancements and a Formal Assessment of Student Learning in System Dynamics

    ERIC Educational Resources Information Center

    Gorlewicz, Jenna L.; Kratchman, Louis B.; Webster, Robert J., III

    2014-01-01

    The haptic paddle is a force-feedback joystick used at several universities in teaching System Dynamics, a core mechanical engineering undergraduate course where students learn to model dynamic systems in several domains. A second goal of the haptic paddle is to increase the accessibility of robotics and haptics by providing a low-cost device for…

  15. Comparing two types of navigational interfaces for Virtual Reality.

    PubMed

    Teixeira, Luís; Vilar, Elisângela; Duarte, Emília; Rebelo, Francisco; da Silva, Fernando Moreira

    2012-01-01

    Previous studies suggest significant differences between navigating virtual environments in a life-like walking manner (i.e., using treadmills or walk-in-place techniques) and virtual navigation (i.e., flying while really standing). The latter option, which usually involves hand-centric devices (e.g., joysticks), is the most common in Virtual Reality-based studies, mostly due to low costs, less space and technology demands. However, recently, new interaction devices, originally conceived for videogames have become available offering interesting potentialities for research. This study aimed to explore the potentialities of the Nintendo Wii Balance Board as a navigation interface in a Virtual Environment presented in an immersive Virtual Reality system. Comparing participants' performance while engaged in a simulated emergency egress allows determining the adequacy of such alternative navigation interface on the basis of empirical results. Forty university students participated in this study. Results show that participants were more efficient when performing navigation tasks using the Joystick than with the Balance Board. However there were no significantly differences in the behavioral compliance with exit signs. Therefore, this study suggests that, at least for tasks similar to the studied, the Balance Board have good potentiality to be used as a navigation interface for Virtual Reality systems.

  16. Security Engineering Project

    DTIC Science & Technology

    2015-01-31

    from a wireless joystick console broadcasting at 2.4 GHz. Figure 6. GTRI Airborne Unmanned Sensor System As shown in Figure 7 the autopilot has a...generating wind turbines , and video reconnaissance systems on unmanned aerial vehicles (UAVs). The most basic decision problem in designing a...chosen test UAV case was the GTRI Aerial Unmanned Sensor System (GAUSS) aircraft. The GAUSS platform is a small research UAV with a widely used

  17. Synergistic Effects on the Elderly People's Motor Control by Wearable Skin-Stretch Device Combined with Haptic Joystick

    PubMed Central

    Yoon, Han U.; Anil Kumar, Namita; Hur, Pilwon

    2017-01-01

    Cutaneous sensory feedback can be used to provide additional sensory cues to a person performing a motor task where vision is a dominant feedback signal. A haptic joystick has been widely used to guide a user by providing force feedback. However, the benefit of providing force feedback is still debatable due to performance dependency on factors such as the user's skill-level, task difficulty. Meanwhile, recent studies have shown the feasibility of improving a motor task performance by providing skin-stretch feedback. Therefore, a combination of two aforementioned feedback types is deemed to be promising to promote synergistic effects to consistently improve the person's motor performance. In this study, we aimed at identifying the effect of the combined haptic and skin-stretch feedbacks on the aged person's driving motor performance. For the experiment, 15 healthy elderly subjects (age 72.8 ± 6.6 years) were recruited and were instructed to drive a virtual power-wheelchair through four different courses with obstacles. Four augmented sensory feedback conditions were tested: no feedback, force feedback, skin-stretch feedback, and a combination of both force and skin-stretch feedbacks. While the haptic force was provided to the hand by the joystick, the skin-stretch was provided to the steering forearm by a custom-designed wearable skin-stretch device. We tested two hypotheses: (i) an elderly individual's motor control would benefit from receiving information about a desired trajectory from multiple sensory feedback sources, and (ii) the benefit does not depend on task difficulty. Various metrics related to skills and safety were used to evaluate the control performance. Repeated measure ANOVA was performed for those metrics with two factors: task scenario and the type of the augmented sensory feedback. The results revealed that elderly subjects' control performance significantly improved when the combined feedback of both haptic force and skin-stretch feedback was applied. The proposed approach suggest the feasibility to improve people's task performance by the synergistic effects of multiple augmented sensory feedback modalities. PMID:28690514

  18. A Multimodal Adaptive Wireless Control Interface for People With Upper-Body Disabilities.

    PubMed

    Fall, Cheikh Latyr; Quevillon, Francis; Blouin, Martine; Latour, Simon; Campeau-Lecours, Alexandre; Gosselin, Clement; Gosselin, Benoit

    2018-06-01

    This paper describes a multimodal body-machine interface (BoMI) to help individuals with upper-limb disabilities using advanced assistive technologies, such as robotic arms. The proposed system uses a wearable and wireless body sensor network (WBSN) supporting up to six sensor nodes to measure the natural upper-body gesture of the users and translate it into control commands. Natural gesture of the head and upper-body parts, as well as muscular activity, are measured using inertial measurement units (IMUs) and surface electromyography (sEMG) using custom-designed multimodal wireless sensor nodes. An IMU sensing node is attached to a headset worn by the user. It has a size of 2.9 cm 2.9 cm, a maximum power consumption of 31 mW, and provides angular precision of 1. Multimodal patch sensor nodes, including both IMU and sEMG sensing modalities are placed over the user able-body parts to measure the motion and muscular activity. These nodes have a size of 2.5 cm 4.0 cm and a maximum power consumption of 11 mW. The proposed BoMI runs on a Raspberry Pi. It can adapt to several types of users through different control scenarios using the head and shoulder motion, as well as muscular activity, and provides a power autonomy of up to 24 h. JACO, a 6-DoF assistive robotic arm, is used as a testbed to evaluate the performance of the proposed BoMI. Ten able-bodied subjects performed ADLs while operating the AT device, using the Test d'Évaluation des Membres Supérieurs de Personnes Âgées to evaluate and compare the proposed BoMI with the conventional joystick controller. It is shown that the users can perform all tasks with the proposed BoMI, almost as fast as with the joystick controller, with only 30% time overhead on average, while being potentially more accessible to the upper-body disabled who cannot use the conventional joystick controller. Tests show that control performance with the proposed BoMI improved by up to 17% on average, after three trials.

  19. Tilt and Translation Motion Perception during Off Vertical Axis Rotation

    NASA Technical Reports Server (NTRS)

    Wood, Scott J.; Reschke, Millard F.; Clement, Gilles

    2006-01-01

    The effect of stimulus frequency on tilt and translation motion perception was studied during constant velocity off-vertical axis rotation (OVAR), and compared to the effect of stimulus frequency on eye movements. Fourteen healthy subjects were rotated in darkness about their longitudinal axis 10deg and 20deg off-vertical at 0.125 Hz, and 20deg offvertical at 0.5 Hz. Oculomotor responses were recorded using videography, and perceived motion was evaluated using verbal reports and a joystick with four degrees of freedom (pitch and roll tilt, mediallateral and anteriorposterior translation). During the lower frequency OVAR, subjects reported the perception of progressing along the edge of a cone. During higher frequency OVAR, subjects reported the perception of progressing along the edge of an upright cylinder. The modulation of both tilt recorded from the joystick and ocular torsion significantly increased as the tilt angle increased from 10deg to 20deg at 0.125 Hz, and then decreased at 0.5 Hz. Both tilt perception and torsion slightly lagged head orientation at 0.125 Hz. The phase lag of torsion increased at 0.5 Hz, while the phase of tilt perception did not change as a function of frequency. The amplitude of both translation perception recorded from the joystick and horizontal eye movements was negligible at 0.125 Hz and increased as a function of stimulus frequency. While the phase lead of horizontal eye movements decreased at 0.5 Hz, the phase of translation perception did not vary with stimulus frequency and was similar to the phase of tilt perception during all conditions. During dynamic linear acceleration in the absence of other sensory input (canal, vision) a change in stimulus frequency alone elicits similar changes in the amplitude of both self motion perception and eye movements. However, in contrast to the eye movements, the phase of both perceived tilt and translation motion is not altered by stimulus frequency. We conclude that the neural processing to distinguish tilt and translation linear acceleration stimuli differs between eye movements and motion perception.

  20. Helping Video Games Rewire "Our Minds"

    NASA Technical Reports Server (NTRS)

    Pope, Alan T.; Palsson, Olafur S.

    2001-01-01

    Biofeedback-modulated video games are games that respond to physiological signals as well as mouse, joystick or game controller input; they embody the concept of improving physiological functioning by rewarding specific healthy body signals with success at playing a video game. The NASA patented biofeedback-modulated game method blends biofeedback into popular off-the- shelf video games in such a way that the games do not lose their entertainment value. This method uses physiological signals (e.g., electroencephalogram frequency band ratio) not simply to drive a biofeedback display directly, or periodically modify a task as in other systems, but to continuously modulate parameters (e.g., game character speed and mobility) of a game task in real time while the game task is being performed by other means (e.g., a game controller). Biofeedback-modulated video games represent a new generation of computer and video game environments that train valuable mental skills beyond eye-hand coordination. These psychophysiological training technologies are poised to exploit the revolution in interactive multimedia home entertainment for the personal improvement, not just the diversion, of the user.

  1. Design of a solar tracking interactive kiosk

    NASA Astrophysics Data System (ADS)

    Greene, Nathaniel R.; Brunskill, Jeffrey C.

    2017-01-01

    A two-axis solar tracker and its interactive kiosk were designed by an interdisciplinary team of students and faculty. The objective was to develop a publicly accessible kiosk that would facilitate the study of energy usage and production on campus. Tracking is accomplished by an open-loop algorithm, microcontroller, and ham radio rotator. Solar panel output is monitored in real time and displayed to the public with lights and digits that can be read by the casual passersby. While maximum power point tracking is the most accurate means of quantifying the output power of a photovoltaic panel, simplicity and design constraints dictated the use of short-circuit current as a proxy for power. A touchscreen display allows kiosk visitors to compare two solar panels, an automatic tracker that faces the sun, and an identical panel whose elevation and azimuth can be controlled with a virtual joystick. This project was a capstone experience for students in physics/engineering, computer science, and instructional technology. We discuss technical challenges and design choices, as well as the educational goals of the kiosk.

  2. Toward brain-computer interface based wheelchair control utilizing tactually-evoked event-related potentials

    PubMed Central

    2014-01-01

    Background People with severe disabilities, e.g. due to neurodegenerative disease, depend on technology that allows for accurate wheelchair control. For those who cannot operate a wheelchair with a joystick, brain-computer interfaces (BCI) may offer a valuable option. Technology depending on visual or auditory input may not be feasible as these modalities are dedicated to processing of environmental stimuli (e.g. recognition of obstacles, ambient noise). Herein we thus validated the feasibility of a BCI based on tactually-evoked event-related potentials (ERP) for wheelchair control. Furthermore, we investigated use of a dynamic stopping method to improve speed of the tactile BCI system. Methods Positions of four tactile stimulators represented navigation directions (left thigh: move left; right thigh: move right; abdomen: move forward; lower neck: move backward) and N = 15 participants delivered navigation commands by focusing their attention on the desired tactile stimulus in an oddball-paradigm. Results Participants navigated a virtual wheelchair through a building and eleven participants successfully completed the task of reaching 4 checkpoints in the building. The virtual wheelchair was equipped with simulated shared-control sensors (collision avoidance), yet these sensors were rarely needed. Conclusion We conclude that most participants achieved tactile ERP-BCI control sufficient to reliably operate a wheelchair and dynamic stopping was of high value for tactile ERP classification. Finally, this paper discusses feasibility of tactile ERPs for BCI based wheelchair control. PMID:24428900

  3. Method and apparatus for providing high bandwidth, low noise mechanical I/O for computer systems

    DOEpatents

    Rosenberg, Louis B.

    1998-01-01

    A method and apparatus for providing high bandwidth and low noise mechanical input and output for computer systems. A gimbal mechanism provides two revolute degrees of freedom to an object about two axes of rotation. A linear axis member is coupled to the gimbal mechanism at the intersection of the two axes of rotation. The linear axis member is capable of being translated along a third axis to provide a third degree of freedom. The user object is coupled to the linear axis member and is thus translatable along the third axis so that the object can be moved along all three degrees of freedom. Transducers associated with the provided degrees of freedom include sensors and actuators and provide an electromechanical interface between the object and a digital processing system. Capstan drive mechanisms transmit forces between the transducers and the object. The linear axis member can also be rotated about its lengthwise axis to provide a fourth degree of freedom, and, optionally, a floating gimbal mechanism is coupled to the linear axis member to provide fifth and sixth degrees of freedom to an object. Transducer sensors are associated with the fourth, fifth, and sixth degrees of freedom. The interface is well suited for simulations of medical procedures and simulations in which an object such as a stylus or a joystick is moved and manipulated by the user.

  4. Multiple degree-of-freedom mechanical interface to a computer system

    DOEpatents

    Rosenberg, Louis B.

    2001-01-01

    A method and apparatus for providing high bandwidth and low noise mechanical input and output for computer systems. A gimbal mechanism provides two revolute degrees of freedom to an object about two axes of rotation. A linear axis member is coupled to the gimbal mechanism at the intersection of the two axes of rotation. The linear axis member is capable of being translated along a third axis to provide a third degree of freedom. The user object is coupled to the linear axis member and is thus translatable along the third axis so that the object can be moved along all three degrees of freedom. Transducers associated with the provided degrees of freedom include sensors and actuators and provide an electromechanical interface between the object and a digital processing system. Capstan drive mechanisms transmit forces between the transducers and the object. The linear axis member can also be rotated about its lengthwise axis to provide a fourth degree of freedom, and, optionally, a floating gimbal mechanism is coupled to the linear axis member to provide fifth and sixth degrees of freedom to an object. Transducer sensors are associated with the fourth, fifth, and sixth degrees of freedom. The interface is well suited for simulations of medical procedures and simulations in which an object such as a stylus or a joystick is moved and manipulated by the user.

  5. Study to design and develop remote manipulator systems

    NASA Technical Reports Server (NTRS)

    Hill, J. W.; Salisbury, J. K., Jr.

    1977-01-01

    A description is given of part of a continuing effort both to develop models for and to augment the performance of humans controlling remote manipulators. The project plan calls for the performance of several standard tasks with a number of different manipulators, controls, and viewing conditions, using an automated performance measuring system; in addition, the project plan calls for the development of a force-reflecting joystick and supervisory display system.

  6. Human-Robot Interface: Issues in Operator Performance, Interface Design, and Technologies

    DTIC Science & Technology

    2006-07-01

    and the use of lightweight portable robotic sensor platforms. 5 robotics has reached a point where some generalities of HRI transcend specific...displays with control devices such as joysticks, wheels, and pedals (Kamsickas, 2003). Typical control stations include panels displaying (a) sensor ...tasks that do not involve mobility and usually involve camera control or data fusion from sensors Active search: Search tasks that involve mobility

  7. Play in America from Pilgrims and Patriots to Kid Jocks and Joystick Jockeys: Or How Play Mirrors Social Change

    ERIC Educational Resources Information Center

    Cross, Gary

    2008-01-01

    Drawing on a range of sources in the history of play, this article discusses how play for all ages mirrors social change, especially but not exclusively in America. The article explores three broad themes from colonial times to the present: first, how play was shaped by changes in work and time at work; second, how play activities were transformed…

  8. Robotic Camera Assistance and Its Benefit in 1033 Traditional Laparoscopic Procedures: Prospective Clinical Trial Using a Joystick-guided Camera Holder.

    PubMed

    Holländer, Sebastian W; Klingen, Hans Joachim; Fritz, Marliese; Djalali, Peter; Birk, Dieter

    2014-11-01

    Despite advances in instruments and techniques in laparoscopic surgery, one thing remains uncomfortable: the camera assistance. The aim of this study was to investigate the benefit of a joystick-guided camera holder (SoloAssist®, Aktormed, Barbing, Germany) for laparoscopic surgery and to compare the robotic assistance to human assistance. 1033 consecutive laparoscopic procedures were performed assisted by the SoloAssist®. Failures and aborts were documented and nine surgeons were interviewed by questionnaire regarding their experiences. In 71 of 1033 procedures, robotic assistance was aborted and the procedure was continued manually, mostly because of frequent changes of position, narrow spaces, and adverse angular degrees. One case of short circuit was reported. Emergency stop was necessary in three cases due to uncontrolled movement into the abdominal cavity. Eight of nine surgeons prefer robotic to human assistance, mostly because of a steady image and self-control. The SoloAssist® robot is a reliable system for laparoscopic procedures. Emergency shutdown was necessary in only three cases. Some minor weak spots could have been identified. Most surgeons prefer robotic assistance to human assistance. We feel that the SoloAssist® makes standard laparoscopic surgery more comfortable and further development is desirable, but it cannot fully replace a human assistant.

  9. The Effectiveness of Simulator Motion in the Transfer of Performance on a Tracking Task Is Influenced by Vision and Motion Disturbance Cues.

    PubMed

    Grundy, John G; Nazar, Stefan; O'Malley, Shannon; Mohrenshildt, Martin V; Shedden, Judith M

    2016-06-01

    To examine the importance of platform motion to the transfer of performance in motion simulators. The importance of platform motion in simulators for pilot training is strongly debated. We hypothesized that the type of motion (e.g., disturbance) contributes significantly to performance differences. Participants used a joystick to perform a target tracking task in a pod on top of a MOOG Stewart motion platform. Five conditions compared training without motion, with correlated motion, with disturbance motion, with disturbance motion isolated to the visual display, and with both correlated and disturbance motion. The test condition involved the full motion model with both correlated and disturbance motion. We analyzed speed and accuracy across training and test as well as strategic differences in joystick control. Training with disturbance cues produced critical behavioral differences compared to training without disturbance; motion itself was less important. Incorporation of disturbance cues is a potentially important source of variance between studies that do or do not show a benefit of motion platforms in the transfer of performance in simulators. Potential applications of this research include the assessment of the importance of motion platforms in flight simulators, with a focus on the efficacy of incorporating disturbance cues during training. © 2016, Human Factors and Ergonomics Society.

  10. Learning dynamic control of body yaw orientation.

    PubMed

    Vimal, Vivekanand Pandey; Lackner, James R; DiZio, Paul

    2018-05-01

    To investigate the role of gravitational cues in the learning of a dynamic balancing task, we placed blindfolded subjects in a device programmed with inverted pendulum dynamics about the yaw axis. Subjects used a joystick to try and maintain a stable orientation at the direction of balance during 20 100 s-long trials. They pressed a trigger button on the joystick to indicate whenever they felt at the direction of balance. Three groups of ten subjects each participated. One group balanced with their body and the yaw axis vertical, and thus did not have gravitational cues to help them to determine their angular position. They showed minimal learning, inaccurate indications of the direction of balance, and a characteristic pattern of positional drifting away from the balance point. A second group balanced with the yaw axis pitched 45° from the gravitational vertical and had gravity relevant position cues. The third group balanced with their yaw axis horizontal where they had gravity-dependent cues about body position in yaw. Groups 2 and 3 showed better initial balancing performance and more learning across trials than Group 1. These results indicate that in the absence of vision, the integration of transient semicircular canal and somatosensory signals about angular acceleration is insufficient for determining angular position during dynamic balancing; direct position-dependent gravity cues are necessary.

  11. A behavioral task for investigating action discovery, selection and switching: comparison between types of reinforcer

    PubMed Central

    Fisher, Simon D.; Gray, Jason P.; Black, Melony J.; Davies, Jennifer R.; Bednark, Jeffery G.; Redgrave, Peter; Franz, Elizabeth A.; Abraham, Wickliffe C.; Reynolds, John N. J.

    2014-01-01

    Action discovery and selection are critical cognitive processes that are understudied at the cellular and systems neuroscience levels. Presented here is a new rodent joystick task suitable to test these processes due to the range of action possibilities that can be learnt while performing the task. Rats learned to manipulate a joystick while progressing through task milestones that required increasing degrees of movement accuracy. In a switching phase designed to measure action discovery, rats were repeatedly required to discover new target positions to meet changing task demands. Behavior was compared using both food and electrical brain stimulation reward (BSR) of the substantia nigra as reinforcement. Rats reinforced with food and those with BSR performed similarly overall, although BSR-treated rats exhibited greater vigor in responding. In the switching phase, rats learnt new actions to adapt to changing task demands, reflecting action discovery processes. Because subjects are required to learn different goal-directed actions, this task could be employed in further investigations of the cellular mechanisms of action discovery and selection. Additionally, this task could be used to assess the behavioral flexibility impairments seen in conditions such as Parkinson's disease and obsessive-compulsive disorder. The versatility of the task will enable cross-species investigations of these impairments. PMID:25477795

  12. A simple, inexpensive, and effective implementation of a vision-guided autonomous robot

    NASA Astrophysics Data System (ADS)

    Tippetts, Beau; Lillywhite, Kirt; Fowers, Spencer; Dennis, Aaron; Lee, Dah-Jye; Archibald, James

    2006-10-01

    This paper discusses a simple, inexpensive, and effective implementation of a vision-guided autonomous robot. This implementation is a second year entrance for Brigham Young University students to the Intelligent Ground Vehicle Competition. The objective of the robot was to navigate a course constructed of white boundary lines and orange obstacles for the autonomous competition. A used electric wheelchair was used as the robot base. The wheelchair was purchased from a local thrift store for $28. The base was modified to include Kegresse tracks using a friction drum system. This modification allowed the robot to perform better on a variety of terrains, resolving issues with last year's design. In order to control the wheelchair and retain the robust motor controls already on the wheelchair the wheelchair joystick was simply removed and replaced with a printed circuit board that emulated joystick operation and was capable of receiving commands through a serial port connection. Three different algorithms were implemented and compared: a purely reactive approach, a potential fields approach, and a machine learning approach. Each of the algorithms used color segmentation methods to interpret data from a digital camera in order to identify the features of the course. This paper will be useful to those interested in implementing an inexpensive vision-based autonomous robot.

  13. The International Ultraviolet Explorer: Case study in spacecraft design

    NASA Technical Reports Server (NTRS)

    Freeman, H. R.; Longanecker, G. W.

    1979-01-01

    The International Ultraviolet Explorer (IUE) is a geosynchronous scientific satellite that was conceived as an international space observatory capable of measuring UV spectra of faint celestial bodies. Simple operational procedures allow the astronomers to joystick the spaceborne telescope about the sky, using familiar ground-based observatory techniques. The present paper deals with the IUE project objectives, the technical problems, constraints, trade-offs, and the problem solving techniques used in the IUE program.

  14. Fully Three-Dimensional Virtual-Reality System

    NASA Technical Reports Server (NTRS)

    Beckman, Brian C.

    1994-01-01

    Proposed virtual-reality system presents visual displays to simulate free flight in three-dimensional space. System, virtual space pod, is testbed for control and navigation schemes. Unlike most virtual-reality systems, virtual space pod would not depend for orientation on ground plane, which hinders free flight in three dimensions. Space pod provides comfortable seating, convenient controls, and dynamic virtual-space images for virtual traveler. Controls include buttons plus joysticks with six degrees of freedom.

  15. Dive and Explore: An Interactive Exhibit That Simulates Making an ROV Dive to a Submarine Volcano, Hatfield Marine Science Visitor Center, Newport, Oregon

    NASA Astrophysics Data System (ADS)

    Weiland, C.; Chadwick, W. W.; Hanshumaker, W.; Osis, V.; Hamilton, C.

    2002-12-01

    We have created a new interactive exhibit in which the user can sit down and simulate that they are making a dive to the seafloor with the remotely operated vehicle (ROV) named ROPOS. The exhibit immerses the user in an interactive experience that is naturally fun but also educational. This new public display is located at the Hatfield Marine Science Visitor Center in Newport, Oregon. The exhibit is designed to look like the real ROPOS control console and includes three video monitors, a PC, a DVD player, an overhead speaker, graphic panels, buttons, lights, dials, and a seat in front of a joystick. The dives are based on real seafloor settings at Axial seamount, an active submarine volcano on the Juan de Fuca Ridge (NE Pacific) that is also the location of a seafloor observatory called NeMO. The user can choose between 1 of 3 different dives sites in the caldera of Axial Volcano. Once a dive is chosen, then the user watches ROPOS being deployed and then arrives into a 3-D computer-generated seafloor environment that is based on the real world but is easier to visualize and navigate. Once on the bottom, the user is placed within a 360 degree panorama and can look in all directions by manipulating the joystick. By clicking on markers embedded in the scene, the user can then either move to other panorama locations via movies that travel through the 3-D virtual environment, or they can play video clips from actual ROPOS dives specifically related to that scene. Audio accompanying the video clips informs the user where they are going or what they are looking at. After the user is finished exploring the dive site they end the dive by leaving the bottom and watching the ROV being recovered onto the ship at the surface. The user can then choose a different dive or make the same dive again. Within the three simulated dives there are a total of 6 arrival and departure movies, 7 seafloor panoramas, 12 travel movies, and 23 ROPOS video clips. The exhibit software was created with Macromedia Director using Apple Quicktime and Quicktime VR. The exhibit is based on the NeMO Explorer web site (http://www.pmel.noaa.gov/vents/nemo/explorer.html).

  16. Decentralized real-time simulation of forest machines

    NASA Astrophysics Data System (ADS)

    Freund, Eckhard; Adam, Frank; Hoffmann, Katharina; Rossmann, Juergen; Kraemer, Michael; Schluse, Michael

    2000-10-01

    To develop realistic forest machine simulators is a demanding task. A useful simulator has to provide a close- to-reality simulation of the forest environment as well as the simulation of the physics of the vehicle. Customers demand a highly realistic three dimensional forestry landscape and the realistic simulation of the complex motion of the vehicle even in rough terrain in order to be able to use the simulator for operator training under close-to- reality conditions. The realistic simulation of the vehicle, especially with the driver's seat mounted on a motion platform, greatly improves the effect of immersion into the virtual reality of a simulated forest and the achievable level of education of the driver. Thus, the connection of the real control devices of forest machines to the simulation system has to be supported, i.e. the real control devices like the joysticks or the board computer system to control the crane, the aggregate etc. Beyond, the fusion of the board computer system and the simulation system is realized by means of sensors, i.e. digital and analog signals. The decentralized system structure allows several virtual reality systems to evaluate and visualize the information of the control devices and the sensors. So, while the driver is practicing, the instructor can immerse into the same virtual forest to monitor the session from his own viewpoint. In this paper, we are describing the realized structure as well as the necessary software and hardware components and application experiences.

  17. Augmented reality to the rescue of the minimally invasive surgeon. The usefulness of the interposition of stereoscopic images in the Da Vinci™ robotic console.

    PubMed

    Volonté, Francesco; Buchs, Nicolas C; Pugin, François; Spaltenstein, Joël; Schiltz, Boris; Jung, Minoa; Hagen, Monika; Ratib, Osman; Morel, Philippe

    2013-09-01

    Computerized management of medical information and 3D imaging has become the norm in everyday medical practice. Surgeons exploit these emerging technologies and bring information previously confined to the radiology rooms into the operating theatre. The paper reports the authors' experience with integrated stereoscopic 3D-rendered images in the da Vinci surgeon console. Volume-rendered images were obtained from a standard computed tomography dataset using the OsiriX DICOM workstation. A custom OsiriX plugin was created that permitted the 3D-rendered images to be displayed in the da Vinci surgeon console and to appear stereoscopic. These rendered images were displayed in the robotic console using the TilePro multi-input display. The upper part of the screen shows the real endoscopic surgical field and the bottom shows the stereoscopic 3D-rendered images. These are controlled by a 3D joystick installed on the console, and are updated in real time. Five patients underwent a robotic augmented reality-enhanced procedure. The surgeon was able to switch between the classical endoscopic view and a combined virtual view during the procedure. Subjectively, the addition of the rendered images was considered to be an undeniable help during the dissection phase. With the rapid evolution of robotics, computer-aided surgery is receiving increasing interest. This paper details the authors' experience with 3D-rendered images projected inside the surgical console. The use of this intra-operative mixed reality technology is considered very useful by the surgeon. It has been shown that the usefulness of this technique is a step toward computer-aided surgery that will progress very quickly over the next few years. Copyright © 2012 John Wiley & Sons, Ltd.

  18. Serious Gaming Technologies Support Human Factors Investigations of Advanced Interfaces for Semi-Autonomous Vehicles

    DTIC Science & Technology

    2006-06-01

    conventional camera vs. thermal imager vs. night vision; camera field of view (narrow, wide, panoramic); keyboard + mouse vs. joystick control vs...motorised platform which could scan the immediate area, producing a 360o panorama of “stitched-together” digital pictures. The picture file, together with...VBS was used to automate the process of creating a QuickTime panorama (.mov or .qt), which includes the initial retrieval of the images, the

  19. Variable-Reluctance Motor For Electric Vehicles

    NASA Technical Reports Server (NTRS)

    Lang, Jeffrey H.

    1987-01-01

    Report describes research on variable-reluctance electric-motor drive for eventual use in electric-vehicle propulsion. Primary design and performance criteria were torque and power output per unit mass of motor, cost, and drive efficiency. For each criterion, optimized drive design developed, and designs unified to yield single electric-vehicle drive. Scaled-down motor performed as expected. Prototype of paraplegic lift operated by toggle switch and joystick. Lift plugs into household electrical outlet for recharging when not in use.

  20. Communications Modeling of Training and Simulation Traffic in a Tactical Internet

    DTIC Science & Technology

    2006-08-01

    Florida. VIDEO GAME TRAINING Eric Minton Today’s Officer January 24, 2005 Here is something parents everywhere won’t want to read: video ...experience, video games make for a wiser and more adaptable individual and team player. That is what the U.S. military is discovering as each branch...embraces video games and gaming technology in their training regimens. This is more just catering to a generation that knew the joy of joysticks while

  1. Performance Evaluation of a Mobile Touchscreen Interface for Assistive Robotic Manipulators: A Pilot Study.

    PubMed

    Chung, Cheng-Shiu; Ka, Hyun W; Wang, Hongu; Ding, Dan; Kelleher, Annmarie; Cooper, Rory A

    2017-01-01

    Background: Assistive robotic manipulators (ARMs) have been developed to provide enhanced assistance and independence in performance of daily activities among people with spinal cord injury when a caregiver is not on site. However, the current commercial ARM user interfaces (UIs) may be difficult to learn and control. A touchscreen mobile UI was developed to overcome these challenges. Objective: The object of this study was to evaluate the performance between 2 ARM UIs, touchscreen and the original joystick, using an ARM evaluation tool (ARMET). Methods: This is a pilot study of people with upper extremity impairments ( N = 8). Participants were trained on 2 UIs, and then they chose one to use when performing 3 tasks on the ARMET: flipping a toggle switch, pushing down a door handle, and turning a knob. Task completion time, mean velocity, and open interviews were the main outcome measurements. Results: Among 8 novice participants, 7 chose the touchscreen UI and 1 chose the joystick UI. All participants could complete the ARMET tasks independently. Use of the touchscreen UI resulted in enhanced ARMET performance (higher mean moving speed and faster task completion). Conclusions: Mobile ARM UIs demonstrated easier learning experience, less physical effort, and better ARMET performance. The improved performance, the accessibility, and lower physical effort suggested that the touchscreen UI might be an efficient tool for the ARM users.

  2. Automatic Avoidance Tendencies in Individuals with Contamination-Related Obsessive-Compulsive Symptoms

    PubMed Central

    Najmi, Sadia; Kuckertz, Jennie M.; Amir, Nader

    2010-01-01

    We used an Approach-Avoidance Task (AAT) to examine response to threatening stimuli in 20 individuals high in contamination-related obsessive-compulsive symptoms (HCs) and 21 individuals low in contamination-related obsessive-compulsive symptoms (LCs). Participants were instructed to respond to contamination-related and neutral pictures by pulling a joystick towards themselves or by pushing it away from themselves. Moving the joystick changed the size of the image to simulate approaching or distancing oneself from the object. Consistent with our hypothesis, the HC group was significantly slower in pulling contamination-related pictures than in pulling neutral pictures, whereas in the LC group there was no difference between speed of pulling contamination-related pictures and neutral pictures. Contrary to our hypothesis, we did not find support for faster pushing away of contamination-related pictures than neutral pictures by the HC group. Moreover, the degree of avoidance of contamination-related stimuli when pulling – but not when pushing – was significantly correlated with self-reported contamination-related obsessive-compulsive symptoms. These results suggest a biased behavioral response for threatening objects in individuals high in contamination fears only when inhibiting the prepotent response to avoid threatening stimuli and not when performing a practiced avoidance response. Thus, our results validate the use of the AAT as a measure of inhibited and uninhibited automatic avoidance reactions to emotional information in individuals with contamination-related obsessive-compulsive symptoms. PMID:20650448

  3. Words putting pain in motion: the generalization of pain-related fear within an artificial stimulus category

    PubMed Central

    Bennett, Marc P.; Meulders, Ann; Baeyens, Frank; Vlaeyen, Johan W. S.

    2015-01-01

    Patients with chronic pain are often fearful of movements that never featured in painful episodes. This study examined whether a neutral movement’s conceptual relationship with pain-relevant stimuli could precipitate pain-related fear; a process known as symbolic generalization. As a secondary objective, we also compared experiential and verbal fear learning in the generalization of pain-related fear. We conducted an experimental study with 80 healthy participants who were recruited through an online experimental management system (Mage = 23.04 years, SD = 6.80 years). First, two artificial categories were established wherein nonsense words and joystick arm movements were equivalent. Using a between-groups design, nonsense words from one category were paired with either an electrocutaneous stimulus (pain-US) or threatening information, while nonsense words from the other category were paired with no pain-US or safety information. During a final testing phase, participants were prompted to perform specific joystick arm movements that were never followed by a pain-US, although they were informed that it could occur. The results showed that movements equivalent to the pain-relevant nonsense words evoked heightened pain-related fear as measured by pain-US expectancy, fear of pain, and unpleasantness ratings. Also, experience with the pain-US evinced stronger acquisition and generalization compared to experience with threatening information. The clinical importance and theoretical implications of these findings are discussed. PMID:25983704

  4. Comparison of gesture and conventional interaction techniques for interventional neuroradiology.

    PubMed

    Hettig, Julian; Saalfeld, Patrick; Luz, Maria; Becker, Mathias; Skalej, Martin; Hansen, Christian

    2017-09-01

    Interaction with radiological image data and volume renderings within a sterile environment is a challenging task. Clinically established methods such as joystick control and task delegation can be time-consuming and error-prone and interrupt the workflow. New touchless input modalities may have the potential to overcome these limitations, but their value compared to established methods is unclear. We present a comparative evaluation to analyze the value of two gesture input modalities (Myo Gesture Control Armband and Leap Motion Controller) versus two clinically established methods (task delegation and joystick control). A user study was conducted with ten experienced radiologists by simulating a diagnostic neuroradiological vascular treatment with two frequently used interaction tasks in an experimental operating room. The input modalities were assessed using task completion time, perceived task difficulty, and subjective workload. Overall, the clinically established method of task delegation performed best under the study conditions. In general, gesture control failed to exceed the clinical input approach. However, the Myo Gesture Control Armband showed a potential for simple image selection task. Novel input modalities have the potential to take over single tasks more efficiently than clinically established methods. The results of our user study show the relevance of task characteristics such as task complexity on performance with specific input modalities. Accordingly, future work should consider task characteristics to provide a useful gesture interface for a specific use case instead of an all-in-one solution.

  5. An egocentric vision based assistive co-robot.

    PubMed

    Zhang, Jingzhe; Zhuang, Lishuo; Wang, Yang; Zhou, Yameng; Meng, Yan; Hua, Gang

    2013-06-01

    We present the prototype of an egocentric vision based assistive co-robot system. In this co-robot system, the user is wearing a pair of glasses with a forward looking camera, and is actively engaged in the control loop of the robot in navigational tasks. The egocentric vision glasses serve for two purposes. First, it serves as a source of visual input to request the robot to find a certain object in the environment. Second, the motion patterns computed from the egocentric video associated with a specific set of head movements are exploited to guide the robot to find the object. These are especially helpful for quadriplegic individuals who do not have needed hand functionality for interaction and control with other modalities (e.g., joystick). In our co-robot system, when the robot does not fulfill the object finding task in a pre-specified time window, it would actively solicit user controls for guidance. Then the users can use the egocentric vision based gesture interface to orient the robot towards the direction of the object. After that the robot will automatically navigate towards the object until it finds it. Our experiments validated the efficacy of the closed-loop design to engage the human in the loop.

  6. An assisted navigation training framework based on judgment theory using sparse and discrete human-machine interfaces.

    PubMed

    Lopes, Ana C; Nunes, Urbano

    2009-01-01

    This paper aims to present a new framework to train people with severe motor disabilities steering an assisted mobile robot (AMR), such as a powered wheelchair. Users with high level of motor disabilities are not able to use standard HMIs, which provide a continuous command signal (e. g. standard joystick). For this reason HMIs providing a small set of simple commands, which are sparse and discrete in time must be used (e. g. scanning interface, or brain computer interface), making very difficult to steer the AMR. In this sense, the assisted navigation training framework (ANTF) is designed to train users driving the AMR, in indoor structured environments, using this type of HMIs. Additionally it provides user characterization on steering the robot, which will later be used to adapt the AMR navigation system to human competence steering the AMR. A rule-based lens (RBL) model is used to characterize users on driving the AMR. Individual judgment performance choosing the best manoeuvres is modeled using a genetic-based policy capturing (GBPC) technique characterized to infer non-compensatory judgment strategies from human decision data. Three user models, at three different learning stages, using the RBL paradigm, are presented.

  7. Cursor control by Kalman filter with a non-invasive body–machine interface

    PubMed Central

    Seáñez-González, Ismael; Mussa-Ivaldi, Ferdinando A

    2015-01-01

    Objective We describe a novel human–machine interface for the control of a two-dimensional (2D) computer cursor using four inertial measurement units (IMUs) placed on the user’s upper-body. Approach A calibration paradigm where human subjects follow a cursor with their body as if they were controlling it with their shoulders generates a map between shoulder motions and cursor kinematics. This map is used in a Kalman filter to estimate the desired cursor coordinates from upper-body motions. We compared cursor control performance in a centre-out reaching task performed by subjects using different amounts of information from the IMUs to control the 2D cursor. Main results Our results indicate that taking advantage of the redundancy of the signals from the IMUs improved overall performance. Our work also demonstrates the potential of non-invasive IMU-based body–machine interface systems as an alternative or complement to brain–machine interfaces for accomplishing cursor control in 2D space. Significance The present study may serve as a platform for people with high-tetraplegia to control assistive devices such as powered wheelchairs using a joystick. PMID:25242561

  8. Experimental evaluation of the concept of supevisory manipulation

    NASA Technical Reports Server (NTRS)

    Brooks, T. L.; Sheridan, T. B.

    1982-01-01

    A computer-controlled teleoperator system which is based on task-referenced sensor-aided control has been developed to study supervisory manipulation. This system, called SUPERMAN, is capable of performing complicated tasks in real-time by utilizing the operator for high-level functions related to the unpredictable portions of a task, while the subordinate machine performs the more well-defined subtasks under human supervison. To determine whether supervisory control schemes such as these offer any advantage over manual control under real-time conditions, a number of experiments involving both simple and complicated tasks were performed. Six representative tasks were chosen for the study: (1) obtaining a tool from a rack, (2) returning the tool to the rack, (3) removing a nut, (4) placing samples in a storage bin, (5) opening and closing a valve, and (6) digging with a shovel. The experiments were performed under simulated conditions using four forms of manual control (i.e., switch rate, joystick rate, master-slave position control, and master-slave with force feedback), as well as supervisory control. Through these experiments the effectiveness and quality of control were evaluated on the basis of the time required to complete each portion of the task and the type and number of errors which occurred.

  9. Extending human proprioception to cyber-physical systems

    NASA Astrophysics Data System (ADS)

    Keller, Kevin; Robinson, Ethan; Dickstein, Leah; Hahn, Heidi A.; Cattaneo, Alessandro; Mascareñas, David

    2016-04-01

    Despite advances in computational cognition, there are many cyber-physical systems where human supervision and control is desirable. One pertinent example is the control of a robot arm, which can be found in both humanoid and commercial ground robots. Current control mechanisms require the user to look at several screens of varying perspective on the robot, then give commands through a joystick-like mechanism. This control paradigm fails to provide the human operator with an intuitive state feedback, resulting in awkward and slow behavior and underutilization of the robot's physical capabilities. To overcome this bottleneck, we introduce a new human-machine interface that extends the operator's proprioception by exploiting sensory substitution. Humans have a proprioceptive sense that provides us information on how our bodies are configured in space without having to directly observe our appendages. We constructed a wearable device with vibrating actuators on the forearm, where frequency of vibration corresponds to the spatial configuration of a robotic arm. The goal of this interface is to provide a means to communicate proprioceptive information to the teleoperator. Ultimately we will measure the change in performance (time taken to complete the task) achieved by the use of this interface.

  10. Semi-Autonomous Vehicle Project

    NASA Technical Reports Server (NTRS)

    Stewart, Christopher

    2016-01-01

    The primary objective this summer is "evaluating standards for wireless architecture for the internet of things". The Internet of Things is the network of physical objects or "things" embedded with electronics, software, sensors and network connectivity which enables these objects to collect and exchange data and make decisions based on said data. This was accomplished by creating a semi-autonomous vehicle that takes advantage of multiple sensors, cameras, and onboard computers and combined them with a mesh network which enabled communication across large distances with little to no interruption. The mesh network took advantage of what is known as DTN - Disruption Tolerant Networking which according to NASA is the new communications protocol that is "the first step towards interplanetary internet." The use of DTN comes from the fact that it will store information if an interruption in communications is detected and even forward that information via other relays within range so that the data is not lost. This translates well into the project because as the car moves further away from whatever is sending it commands (in this case a joystick), the information can still be forwarded to the car with little to no loss of information thanks to the mesh nodes around the driving area.

  11. Upper Body-Based Power Wheelchair Control Interface for Individuals With Tetraplegia.

    PubMed

    Thorp, Elias B; Abdollahi, Farnaz; Chen, David; Farshchiansadegh, Ali; Lee, Mei-Hua; Pedersen, Jessica P; Pierella, Camilla; Roth, Elliot J; Seanez Gonzalez, Ismael; Mussa-Ivaldi, Ferdinando A

    2016-02-01

    Many power wheelchair control interfaces are not sufficient for individuals with severely limited upper limb mobility. The majority of controllers that do not rely on coordinated arm and hand movements provide users a limited vocabulary of commands and often do not take advantage of the user's residual motion. We developed a body-machine interface (BMI) that leverages the flexibility and customizability of redundant control by using high dimensional changes in shoulder kinematics to generate proportional control commands for a power wheelchair. In this study, three individuals with cervical spinal cord injuries were able to control a power wheelchair safely and accurately using only small shoulder movements. With the BMI, participants were able to achieve their desired trajectories and, after five sessions driving, were able to achieve smoothness that was similar to the smoothness with their current joystick. All participants were twice as slow using the BMI however improved with practice. Importantly, users were able to generalize training controlling a computer to driving a power wheelchair, and employed similar strategies when controlling both devices. Overall, this work suggests that the BMI can be an effective wheelchair control interface for individuals with high-level spinal cord injuries who have limited arm and hand control.

  12. Prototype of an auto-calibrating, context-aware, hybrid brain-computer interface.

    PubMed

    Faller, J; Torrellas, S; Miralles, F; Holzner, C; Kapeller, C; Guger, C; Bund, J; Müller-Putz, G R; Scherer, R

    2012-01-01

    We present the prototype of a context-aware framework that allows users to control smart home devices and to access internet services via a Hybrid BCI system of an auto-calibrating sensorimotor rhythm (SMR) based BCI and another assistive device (Integra Mouse mouth joystick). While there is extensive literature that describes the merit of Hybrid BCIs, auto-calibrating and co-adaptive ERD BCI training paradigms, specialized BCI user interfaces, context-awareness and smart home control, there is up to now, no system that includes all these concepts in one integrated easy-to-use framework that can truly benefit individuals with severe functional disabilities by increasing independence and social inclusion. Here we integrate all these technologies in a prototype framework that does not require expert knowledge or excess time for calibration. In a first pilot-study, 3 healthy volunteers successfully operated the system using input signals from an ERD BCI and an Integra Mouse and reached average positive predictive values (PPV) of 72 and 98% respectively. Based on what we learned here we are planning to improve the system for a test with a larger number of healthy volunteers so we can soon bring the system to benefit individuals with severe functional disability.

  13. A learning controller for nonrepetitive robotic operation

    NASA Technical Reports Server (NTRS)

    Miller, W. T., III

    1987-01-01

    A practical learning control system is described which is applicable to complex robotic and telerobotic systems involving multiple feedback sensors and multiple command variables. In the controller, the learning algorithm is used to learn to reproduce the nonlinear relationship between the sensor outputs and the system command variables over particular regions of the system state space, rather than learning the actuator commands required to perform a specific task. The learned information is used to predict the command signals required to produce desired changes in the sensor outputs. The desired sensor output changes may result from automatic trajectory planning or may be derived from interactive input from a human operator. The learning controller requires no a priori knowledge of the relationships between the sensor outputs and the command variables. The algorithm is well suited for real time implementation, requiring only fixed point addition and logical operations. The results of learning experiments using a General Electric P-5 manipulator interfaced to a VAX-11/730 computer are presented. These experiments involved interactive operator control, via joysticks, of the position and orientation of an object in the field of view of a video camera mounted on the end of the robot arm.

  14. Optimal Stimulus Amplitude for Vestibular Stochastic Stimulation to Improve Sensorimotor Function

    NASA Technical Reports Server (NTRS)

    Goel, R.; Kofman, I.; DeDios, Y. E.; Jeevarajan, J.; Stepanyan, V.; Nair, M.; Congdon, S.; Fregia, M.; Cohen, H.; Bloomberg, J. J.; hide

    2014-01-01

    Sensorimotor changes such as postural and gait instabilities can affect the functional performance of astronauts when they transition across different gravity environments. We are developing a method, based on stochastic resonance (SR), to enhance information transfer by applying non-zero levels of external noise on the vestibular system (vestibular stochastic resonance, VSR). Our previous work has shown the advantageous effects of VSR in a balance task of standing on an unstable surface. This technique to improve detection of vestibular signals uses a stimulus delivery system that is wearable or portable and provides imperceptibly low levels of white noise-based binaural bipolar electrical stimulation of the vestibular system. The goal of this project is to determine optimal levels of stimulation for SR applications by using a defined vestibular threshold of motion detection. A series of experiments were carried out to determine a robust paradigm to identify a vestibular threshold that can then be used to recommend optimal stimulation levels for SR training applications customized to each crewmember. Customizing stimulus intensity can maximize treatment effects. The amplitude of stimulation to be used in the VSR application has varied across studies in the literature such as 60% of nociceptive stimulus thresholds. We compared subjects' perceptual threshold with that obtained from two measures of body sway. Each test session was 463s long and consisted of several 15s sinusoidal stimuli, at different current amplitudes (0-2 mA), interspersed with 20-20.5s periods of no stimulation. Subjects sat on a chair with their eyes closed and had to report their perception of motion through a joystick. A force plate underneath the chair recorded medio-lateral shear forces and roll moments. First we determined the percent time during stimulation periods for which perception of motion (activity above a pre-defined threshold) was reported using the joystick, and body sway (two standard deviation of the noise level in the baseline measurement) was detected by the sensors. The percentage time at each stimulation level for motion detection was normalized with respect to the largest value and a logistic regression curve fit was applied to these data. The threshold was defined at the 50% probability of motion detection. Comparison of threshold of motion detection obtained from joystick data versus body sway suggests that perceptual thresholds were significantly lower, and were not impacted by system noise. Further, in order to determine optimal stimulation amplitude to improve balance, two sets of experiments were carried out. In the first set of experiments, all subjects received the same level of stimuli and the intensity of optimal performance was projected back on subjects' vestibular threshold curve. In the second set of experiments, on different subjects, stimulation was administered from 20-400% of subjects' vestibular threshold obtained from joystick data. Preliminary results of our study show that, in general, using stimulation amplitudes at 40-60% of perceptual motion threshold improved balance performance significantly compared to control (no stimulation). The amplitude of vestibular stimulation that improved balance function was predominantly in the range of +/- 100 to +/- 400 micro A. We hypothesize that VSR stimulation will act synergistically with sensorimotor adaptability (SA) training to improve adaptability by increasing utilization of vestibular information and therefore will help us to optimize and personalize a SA countermeasure prescription. This combination will help to significantly reduce the number of days required to recover functional performance to preflight levels after long-duration spaceflight.

  15. Design Handbook for Imagery Interpretation Equipment

    DTIC Science & Technology

    1975-12-01

    Two other sections contain information of a more sections listod. general nature : 0 Cheklists for Specific Displays Section 0 Section 6.0 Workstation...control settings is difficult and for controls (such a fair appraisal of the display. as joysticks and track balls) whose nature prevents the use of scales...RETINALILLUMINANCE3.110 cd/m2 or 0.07 to 33 fL, viewed with a natural N’ (trolands-see Figure 3.2-14)pupil) 0.3 0 30-degree equiluminous surround * Single eye, 2

  16. The Effects of Enhanced Disparity on Manual Control Stereopsis and Tracking Performance.

    DTIC Science & Technology

    1981-06-22

    Modestino for her help in drawing the figures, and Margaret Armour for typing the manuscript. This research was supported by the U.S. Air Force Office of...had both eyes open, but only one of the optical channels transmitted an image. ------- DRAPE 4’ 4-1 Go, IPD JOYSTICK Figure 1. Diagram of the...eliminated. To enhance target detectability, a dark blue cloth was draped behind the targets. This dark background spanned ± 50 and had a luminance of

  17. Human Factors Research Task 2006-8722;111: AIMSsim Feature Development II

    DTIC Science & Technology

    2008-01-01

    originally scheduled to end in May 2007. The SOW was amended in May to set the target end date to August 31st, 2007, without any change to the budget...work task identified in the SOW is described below. More details can be found in the User and System manuals. 1. Multiple USB joysticks: This consisted...machine for changing the course of the experiment or saving responses/data. 9. SGE cleanup: This was originally included in the SOW to allow for

  18. Color-Change Detection Activity in the Primate Superior Colliculus.

    PubMed

    Herman, James P; Krauzlis, Richard J

    2017-01-01

    The primate superior colliculus (SC) is a midbrain structure that participates in the control of spatial attention. Previous studies examining the role of the SC in attention have mostly used luminance-based visual features (e.g., motion, contrast) as the stimuli and saccadic eye movements as the behavioral response, both of which are known to modulate the activity of SC neurons. To explore the limits of the SC's involvement in the control of spatial attention, we recorded SC neuronal activity during a task using color, a visual feature dimension not traditionally associated with the SC, and required monkeys to detect threshold-level changes in the saturation of a cued stimulus by releasing a joystick during maintained fixation. Using this color-based spatial attention task, we found substantial cue-related modulation in all categories of visually responsive neurons in the intermediate layers of the SC. Notably, near-threshold changes in color saturation, both increases and decreases, evoked phasic bursts of activity with magnitudes as large as those evoked by stimulus onset. This change-detection activity had two distinctive features: activity for hits was larger than for misses, and the timing of change-detection activity accounted for 67% of joystick release latency, even though it preceded the release by at least 200 ms. We conclude that during attention tasks, SC activity denotes the behavioral relevance of the stimulus regardless of feature dimension and that phasic event-related SC activity is suitable to guide the selection of manual responses as well as saccadic eye movements.

  19. SpaceDock: A Performance Task Platform for Spaceflight Operations

    NASA Technical Reports Server (NTRS)

    Marshburn, Thomas H.; Strangman, Gary E.; Strauss, Monica S.; Sutton, Jeffrey P.

    2003-01-01

    Preliminary evidence during both short- and long-duration spaceflight indicates that perceptual-motor coordination changes occur and persist in-flight. However, there is presently no in-flight method for evaluating astronaut performance on mission-critical tasks such as docking. We present a portable platform we have developed for attempting and evaluating docking, and describe the results of a pilot study wherein flight novices learned the docking task. Methods: A dual-joystick, six degrees of freedom platform-called SpaceDock-was developed to enable portable, adaptable performance testing in a spaceflight operations setting. Upon this platform, a simplified docking task was created, involving a constant rate of approach towards a docking target and requiring the user to correct translation in two dimensions and attitude orientation along one dimension (either pitch or roll). Ten flight naive subjects performed the task over a 45 min period and all joystick inputs and timings were collected, from which we could successfully reconstruct travel paths, input profiles and relative target displacements. Results: Subjects exhibited significant improvements in docking over the course of the experiment. Learning to compensate for roll-alterations was robust, whereas compensation for pitch-alterations was not in evidence in this population and relatively short training period. Conclusion: The SpaceDock platform can provide a novel method for training and testing subjects, on a spaceflight-relevant task, and can be used to examine behavioral learning, strategy use, and has been adapted for use in brain imaging experiments.

  20. Interface evaluation for soft robotic manipulators

    NASA Astrophysics Data System (ADS)

    Moore, Kristin S.; Rodes, William M.; Csencsits, Matthew A.; Kwoka, Martha J.; Gomer, Joshua A.; Pagano, Christopher C.

    2006-05-01

    The results of two usability experiments evaluating an interface for the operation of OctArm, a biologically inspired robotic arm modeled after an octopus tentacle, are reported. Due to the many degrees-of-freedom (DOF) for the operator to control, such 'continuum' robotic limbs provide unique challenges for human operators because they do not map intuitively. Two modes have been developed to control the arm and reduce the DOF under the explicit direction of the operator. In coupled velocity (CV) mode, a joystick controls changes in arm curvature. In end-effector (EE) mode, a joystick controls the arm by moving the position of an endpoint along a straight line. In Experiment 1, participants used the two modes to grasp objects placed at different locations in a virtual reality modeling language (VRML). Objective measures of performance and subjective preferences were recorded. Results revealed lower grasp times and a subjective preference for the CV mode. Recommendations for improving the interface included providing additional feedback and implementation of an error recovery function. In Experiment 2, only the CV mode was tested with improved training of participants and several changes to the interface. The error recovery function was implemented, allowing participants to reverse through previously attained positions. The mean time to complete the trials in the second usability test was reduced by more than 4 minutes compared with the first usability test, confirming the interface changes improved performance. The results of these tests will be incorporated into future versions of the arm and improve future usability tests.

  1. Earth orbital teleoperator manipulator system evaluation program

    NASA Technical Reports Server (NTRS)

    Brye, R. G.; Frederick, P. N.; Kirkpatrick, M., III; Shields, N. L., Jr.

    1977-01-01

    The operator's ability to perform five manipulator tip movements while using monoptic and stereoptic video systems was assessed. Test data obtained were compared with previous results to determine the impact of camera placement and stereoptic viewing on manipulator system performance. The tests were performed using the NASA MSFC extendible stiff arm Manipulator and an analog joystick controller. Two basic manipulator tasks were utilized. The minimum position change test required the operator to move the manipulator arm to touch a target contract. The dexterity test required removal and replacement of pegs.

  2. Adaptive displays and controllers using alternative feedback.

    PubMed

    Repperger, D W

    2004-12-01

    Investigations on the design of haptic (force reflecting joystick or force display) controllers were conducted by viewing the display of force information within the context of several different paradigms. First, using analogies from electrical and mechanical systems, certain schemes of the haptic interface were hypothesized which may improve the human-machine interaction with respect to various criteria. A discussion is given on how this interaction benefits the electrical and mechanical system. To generalize this concept to the design of human-machine interfaces, three studies with haptic mechanisms were then synthesized and analyzed.

  3. Visual Inference Programming

    NASA Technical Reports Server (NTRS)

    Wheeler, Kevin; Timucin, Dogan; Rabbette, Maura; Curry, Charles; Allan, Mark; Lvov, Nikolay; Clanton, Sam; Pilewskie, Peter

    2002-01-01

    The goal of visual inference programming is to develop a software framework data analysis and to provide machine learning algorithms for inter-active data exploration and visualization. The topics include: 1) Intelligent Data Understanding (IDU) framework; 2) Challenge problems; 3) What's new here; 4) Framework features; 5) Wiring diagram; 6) Generated script; 7) Results of script; 8) Initial algorithms; 9) Independent Component Analysis for instrument diagnosis; 10) Output sensory mapping virtual joystick; 11) Output sensory mapping typing; 12) Closed-loop feedback mu-rhythm control; 13) Closed-loop training; 14) Data sources; and 15) Algorithms. This paper is in viewgraph form.

  4. Lightweight Towed Howitzer Demonstrator. Phase 1 and Partial Phase 2. Volume D3. Part 1. Structural Analysis of System.

    DTIC Science & Technology

    1987-04-01

    Volume D3 - Part I Structural Analysis of System DTIC ELECTE a MApril 1987 SE 03 O0 Contract Number DAAA21-86-C-0047 FMC CORPORATION Northern Ordnance... system , In turn. facilitated crew reductilon via hydraulic emplacement, .four-way Joystick tube- lay, and _power ralming. . MC completed C;oncep)t...D3 Structural Analysis of System PART I D3/050 Table of Contents D3/100 Structural Analysis of SystemUD3/110 CXL Memo: October 3, 1986 D3/120 o

  5. Device Control Using Gestures Sensed from EMG

    NASA Technical Reports Server (NTRS)

    Wheeler, Kevin R.

    2003-01-01

    In this paper we present neuro-electric interfaces for virtual device control. The examples presented rely upon sampling Electromyogram data from a participants forearm. This data is then fed into pattern recognition software that has been trained to distinguish gestures from a given gesture set. The pattern recognition software consists of hidden Markov models which are used to recognize the gestures as they are being performed in real-time. Two experiments were conducted to examine the feasibility of this interface technology. The first replicated a virtual joystick interface, and the second replicated a keyboard.

  6. Laparoscopic simulation interface

    DOEpatents

    Rosenberg, Louis B.

    2006-04-04

    A method and apparatus for providing high bandwidth and low noise mechanical input and output for computer systems. A gimbal mechanism provides two revolute degrees of freedom to an object about two axes of rotation. A linear axis member is coupled to the gimbal mechanism at the intersection of the two axes of rotation. The linear axis member is capable of being translated along a third axis to provide a third degree of freedom. The user object is coupled to the linear axis member and is thus translatable along the third axis so that the object can be moved along all three degrees of freedom. Transducers associated with the provided degrees of freedom include sensors and actuators and provide an electromechanical interface between the object and a digital processing system. Capstan drive mechanisms transmit forces between the transducers and the object. The linear axis member can also be rotated about its lengthwise axis to provide a fourth degree of freedom, and, optionally, a floating gimbal mechanism is coupled to the linear axis member to provide fifth and sixth degrees of freedom to an object. Transducer sensors are associated with the fourth, fifth, and sixth degrees of freedom. The interface is well suited for simulations of medical procedures and simulations in which an object such as a stylus or a joystick is moved and manipulated by the user.

  7. Virtual reality interface devices in the reorganization of neural networks in the brain of patients with neurological diseases.

    PubMed

    Gatica-Rojas, Valeska; Méndez-Rebolledo, Guillermo

    2014-04-15

    Two key characteristics of all virtual reality applications are interaction and immersion. Systemic interaction is achieved through a variety of multisensory channels (hearing, sight, touch, and smell), permitting the user to interact with the virtual world in real time. Immersion is the degree to which a person can feel wrapped in the virtual world through a defined interface. Virtual reality interface devices such as the Nintendo® Wii and its peripheral nunchuks-balance board, head mounted displays and joystick allow interaction and immersion in unreal environments created from computer software. Virtual environments are highly interactive, generating great activation of visual, vestibular and proprioceptive systems during the execution of a video game. In addition, they are entertaining and safe for the user. Recently, incorporating therapeutic purposes in virtual reality interface devices has allowed them to be used for the rehabilitation of neurological patients, e.g., balance training in older adults and dynamic stability in healthy participants. The improvements observed in neurological diseases (chronic stroke and cerebral palsy) have been shown by changes in the reorganization of neural networks in patients' brain, along with better hand function and other skills, contributing to their quality of life. The data generated by such studies could substantially contribute to physical rehabilitation strategies.

  8. Assessment of wheelchair driving performance in a virtual reality-based simulator

    PubMed Central

    Mahajan, Harshal P.; Dicianno, Brad E.; Cooper, Rory A.; Ding, Dan

    2013-01-01

    Objective To develop a virtual reality (VR)-based simulator that can assist clinicians in performing standardized wheelchair driving assessments. Design A completely within-subjects repeated measures design. Methods Participants drove their wheelchairs along a virtual driving circuit modeled after the Power Mobility Road Test (PMRT) and in a hallway with decreasing width. The virtual simulator was displayed on computer screen and VR screens and participants interacted with it using a set of instrumented rollers and a wheelchair joystick. Driving performances of participants were estimated and compared using quantitative metrics from the simulator. Qualitative ratings from two experienced clinicians were used to estimate intra- and inter-rater reliability. Results Ten regular wheelchair users (seven men, three women; mean age ± SD, 39.5 ± 15.39 years) participated. The virtual PMRT scores from the two clinicians show high inter-rater reliability (78–90%) and high intra-rater reliability (71–90%) for all test conditions. More research is required to explore user preferences and effectiveness of the two control methods (rollers and mathematical model) and the display screens. Conclusions The virtual driving simulator seems to be a promising tool for wheelchair driving assessment that clinicians can use to supplement their real-world evaluations. PMID:23820148

  9. A standard set of upper extremity tasks for evaluating rehabilitation interventions for individuals with complete arm paralysis

    PubMed Central

    Cornwell, Andrew S.; Liao, James Y.; Bryden, Anne M.; Kirsch, Robert F.

    2013-01-01

    We have developed a set of upper extremity functional tasks to guide the design and test the performance of rehabilitation technologies that restore arm motion in people with high tetraplegia. Our goal was to develop a short set of tasks that would be representative of a much larger set of activities of daily living while also being feasible for a unilateral user of an implanted Functional Electrical Stimulation (FES) system. To compile this list of tasks, we reviewed existing clinical outcome measures related to arm and hand function, and were further informed by surveys of patient desires. We ultimately selected a set of five tasks that captured the most common components of movement seen in these tasks, making them highly relevant for assessing FES-restored unilateral arm function in individuals with high cervical spinal cord injury (SCI). The tasks are intended to be used when setting design specifications and for evaluation and standardization of rehabilitation technologies under development. While not unique, this set of tasks will provide a common basis for comparing different interventions (e.g., FES, powered orthoses, robotic assistants) and testing different user command interfaces (e.g., sip-and-puff, head joysticks, brain-computer interfaces). PMID:22773199

  10. Influence of visual path information on human heading perception during rotation.

    PubMed

    Li, Li; Chen, Jing; Peng, Xiaozhe

    2009-03-31

    How does visual path information influence people's perception of their instantaneous direction of self-motion (heading)? We have previously shown that humans can perceive heading without direct access to visual path information. Here we vary two key parameters for estimating heading from optic flow, the field of view (FOV) and the depth range of environmental points, to investigate the conditions under which visual path information influences human heading perception. The display simulated an observer traveling on a circular path. Observers used a joystick to rotate their line of sight until deemed aligned with true heading. Four FOV sizes (110 x 94 degrees, 48 x 41 degrees, 16 x 14 degrees, 8 x 7 degrees) and depth ranges (6-50 m, 6-25 m, 6-12.5 m, 6-9 m) were tested. Consistent with our computational modeling results, heading bias increased with the reduction of FOV or depth range when the display provided a sequence of velocity fields but no direct path information. When the display provided path information, heading bias was not influenced as much by the reduction of FOV or depth range. We conclude that human heading and path perception involve separate visual processes. Path helps heading perception when the display does not contain enough optic-flow information for heading estimation during rotation.

  11. Virtual reality interface devices in the reorganization of neural networks in the brain of patients with neurological diseases

    PubMed Central

    Gatica-Rojas, Valeska; Méndez-Rebolledo, Guillermo

    2014-01-01

    Two key characteristics of all virtual reality applications are interaction and immersion. Systemic interaction is achieved through a variety of multisensory channels (hearing, sight, touch, and smell), permitting the user to interact with the virtual world in real time. Immersion is the degree to which a person can feel wrapped in the virtual world through a defined interface. Virtual reality interface devices such as the Nintendo® Wii and its peripheral nunchuks-balance board, head mounted displays and joystick allow interaction and immersion in unreal environments created from computer software. Virtual environments are highly interactive, generating great activation of visual, vestibular and proprioceptive systems during the execution of a video game. In addition, they are entertaining and safe for the user. Recently, incorporating therapeutic purposes in virtual reality interface devices has allowed them to be used for the rehabilitation of neurological patients, e.g., balance training in older adults and dynamic stability in healthy participants. The improvements observed in neurological diseases (chronic stroke and cerebral palsy) have been shown by changes in the reorganization of neural networks in patients’ brain, along with better hand function and other skills, contributing to their quality of life. The data generated by such studies could substantially contribute to physical rehabilitation strategies. PMID:25206907

  12. Cortical Correlates of Fitts’ Law

    PubMed Central

    Ifft, Peter J.; Lebedev, Mikhail A.; Nicolelis, Miguel A. L.

    2011-01-01

    Fitts’ law describes the fundamental trade-off between movement accuracy and speed: it states that the duration of reaching movements is a function of target size (TS) and distance. While Fitts’ law has been extensively studied in ergonomics and has guided the design of human–computer interfaces, there have been few studies on its neuronal correlates. To elucidate sensorimotor cortical activity underlying Fitts’ law, we implanted two monkeys with multielectrode arrays in the primary motor (M1) and primary somatosensory (S1) cortices. The monkeys performed reaches with a joystick-controlled cursor toward targets of different size. The reaction time (RT), movement time, and movement velocity changed with TS, and M1 and S1 activity reflected these changes. Moreover, modifications of cortical activity could not be explained by changes of movement parameters alone, but required TS as an additional parameter. Neuronal representation of TS was especially prominent during the early RT period where it influenced the slope of the firing rate rise preceding movement initiation. During the movement period, cortical activity was correlated with movement velocity. Neural decoders were applied to simultaneously decode TS and motor parameters from cortical modulations. We suggest that sensorimotor cortex activity reflects the characteristics of both the movement and the target. Classifiers that extract these parameters from cortical ensembles could improve neuroprosthetic control. PMID:22275888

  13. Object-based task-level control: A hierarchical control architecture for remote operation of space robots

    NASA Technical Reports Server (NTRS)

    Stevens, H. D.; Miles, E. S.; Rock, S. J.; Cannon, R. H.

    1994-01-01

    Expanding man's presence in space requires capable, dexterous robots capable of being controlled from the Earth. Traditional 'hand-in-glove' control paradigms require the human operator to directly control virtually every aspect of the robot's operation. While the human provides excellent judgment and perception, human interaction is limited by low bandwidth, delayed communications. These delays make 'hand-in-glove' operation from Earth impractical. In order to alleviate many of the problems inherent to remote operation, Stanford University's Aerospace Robotics Laboratory (ARL) has developed the Object-Based Task-Level Control architecture. Object-Based Task-Level Control (OBTLC) removes the burden of teleoperation from the human operator and enables execution of tasks not possible with current techniques. OBTLC is a hierarchical approach to control where the human operator is able to specify high-level, object-related tasks through an intuitive graphical user interface. Infrequent task-level command replace constant joystick operations, eliminating communications bandwidth and time delay problems. The details of robot control and task execution are handled entirely by the robot and computer control system. The ARL has implemented the OBTLC architecture on a set of Free-Flying Space Robots. The capability of the OBTLC architecture has been demonstrated by controlling the ARL Free-Flying Space Robots from NASA Ames Research Center.

  14. Inquiry style interactive virtual experiments: a case on circular motion

    NASA Astrophysics Data System (ADS)

    Zhou, Shaona; Han, Jing; Pelz, Nathaniel; Wang, Xiaojun; Peng, Liangyu; Xiao, Hua; Bao, Lei

    2011-11-01

    Interest in computer-based learning, especially in the use of virtual reality simulations is increasing rapidly. While there are good reasons to believe that technologies have the potential to improve teaching and learning, how to utilize the technology effectively in teaching specific content difficulties is challenging. To help students develop robust understandings of correct physics concepts, we have developed interactive virtual experiment simulations that have the unique feature of enabling students to experience force and motion via an analogue joystick, allowing them to feel the applied force and simultaneously see its effects. The simulations provide students learning experiences that integrate both scientific representations and low-level sensory cues such as haptic cues under a single setting. In this paper, we introduce a virtual experiment module on circular motion. A controlled study has been conducted to evaluate the impact of using this virtual experiment on students' learning of force and motion in the context of circular motion. The results show that the interactive virtual experiment method is preferred by students and is more effective in helping students grasp the physics concepts than the traditional education method such as problem-solving practices. Our research suggests that well-developed interactive virtual experiments can be useful tools in teaching difficult concepts in science.

  15. Upper Body-Based Power Wheelchair Control Interface for Individuals with Tetraplegia

    PubMed Central

    Thorp, Elias B.; Abdollahi, Farnaz; Chen, David; Farshchiansadegh, Ali; Lee, Mei-Hua; Pedersen, Jessica; Pierella, Camilla; Roth, Elliot J.; Gonzalez, Ismael Seanez; Mussa-Ivaldi, Ferdinando A.

    2016-01-01

    Many power wheelchair control interfaces are not sufficient for individuals with severely limited upper limb mobility. The majority of controllers that do not rely on coordinated arm and hand movements provide users a limited vocabulary of commands and often do not take advantage of the user’s residual motion. We developed a body-machine interface (BMI) that leverages the flexibility and customizability of redundant control by using high dimensional changes in shoulder kinematics to generate proportional controls commands for a power wheelchair. In this study, three individuals with cervical spinal cord injuries were able to control the power wheelchair safely and accurately using only small shoulder movements. With the BMI, participants were able to achieve their desired trajectories and, after five sessions driving, were able to achieve smoothness that was similar to the smoothness with their current joystick. All participants were twice as slow using the BMI however improved with practice. Importantly, users were able to generalize training controlling a computer to driving a power wheelchair, and employed similar strategies when controlling both devices. Overall, this work suggests that the BMI can be an effective wheelchair control interface for individuals with high-level spinal cord injuries who have limited arm and hand control. PMID:26054071

  16. Effects of kinesthetic and cutaneous stimulation during the learning of a viscous force field.

    PubMed

    Rosati, Giulio; Oscari, Fabio; Pacchierotti, Claudio; Prattichizzo, Domenico

    2014-01-01

    Haptic stimulation can help humans learn perceptual motor skills, but the precise way in which it influences the learning process has not yet been clarified. This study investigates the role of the kinesthetic and cutaneous components of haptic feedback during the learning of a viscous curl field, taking also into account the influence of visual feedback. We present the results of an experiment in which 17 subjects were asked to make reaching movements while grasping a joystick and wearing a pair of cutaneous devices. Each device was able to provide cutaneous contact forces through a moving platform. The subjects received visual feedback about joystick's position. During the experiment, the system delivered a perturbation through (1) full haptic stimulation, (2) kinesthetic stimulation alone, (3) cutaneous stimulation alone, (4) altered visual feedback, or (5) altered visual feedback plus cutaneous stimulation. Conditions 1, 2, and 3 were also tested with the cancellation of the visual feedback of position error. Results indicate that kinesthetic stimuli played a primary role during motor adaptation to the viscous field, which is a fundamental premise to motor learning and rehabilitation. On the other hand, cutaneous stimulation alone appeared not to bring significant direct or adaptation effects, although it helped in reducing direct effects when used in addition to kinesthetic stimulation. The experimental conditions with visual cancellation of position error showed slower adaptation rates, indicating that visual feedback actively contributes to the formation of internal models. However, modest learning effects were detected when the visual information was used to render the viscous field.

  17. Evaluation of X-38 Crew Return Vehicle Input Control Devices in a Microgravity Environment

    NASA Technical Reports Server (NTRS)

    Welge, Kirsten; Moore, Alicia; Pope, Ruth Ann; Shivers, Suzette; Fox, Jeffrey

    2000-01-01

    This report was created by students from Longview High School, Longview, Texas. Longview High School was selected from a group of Texas high schools to participate in the 1999 Texas Fly High Program. This program gives Texas high school students a chance to work with NASA engineers to design and fly a real-world experiment aboard the KC-135 during zero-g parabolas. Jeffrey Fox's role was to provide a concept for the experiment and to mentor the students in its design and testing. The students were responsible for executing all phases of the project. The X-38 Project Office at the Lyndon B. Johnson Space Center Johnson Space is designing a crew return vehicle (CRV) to be docked at the International Space Station for crew rescue in an emergency. Vehicle controls will be almost completely automated, but a few functions will be manually controlled. Four crew input control devices were selected for evaluation by Longview High School students as part of the 1999 Texas Fly High program. These were (1) Logitech Trackman Marble (optical trackball), (2) Smart Cat Touchpad. (3) Microsoft SideWinder 3D-Pro Joystick, and (4) Microsoft SideWinder Gamepad. In two flight tests in the KC-135 aircraft and a series of ground tests, the devices were evaluated for ability to maneuver an on-screen cursor, level of accuracy, ease of handling blind operations, and level of user comfort in microgravity. The tests results led to recommendation of further tests with the Joystick and the Trackman by astronauts and actual space station residents.

  18. Landmark-based robust navigation for tactical UGV control in GPS-denied communication-degraded environments

    NASA Astrophysics Data System (ADS)

    Endo, Yoichiro; Balloch, Jonathan C.; Grushin, Alexander; Lee, Mun Wai; Handelman, David

    2016-05-01

    Control of current tactical unmanned ground vehicles (UGVs) is typically accomplished through two alternative modes of operation, namely, low-level manual control using joysticks and high-level planning-based autonomous control. Each mode has its own merits as well as inherent mission-critical disadvantages. Low-level joystick control is vulnerable to communication delay and degradation, and high-level navigation often depends on uninterrupted GPS signals and/or energy-emissive (non-stealth) range sensors such as LIDAR for localization and mapping. To address these problems, we have developed a mid-level control technique where the operator semi-autonomously drives the robot relative to visible landmarks that are commonly recognizable by both humans and machines such as closed contours and structured lines. Our novel solution relies solely on optical and non-optical passive sensors and can be operated under GPS-denied, communication-degraded environments. To control the robot using these landmarks, we developed an interactive graphical user interface (GUI) that allows the operator to select landmarks in the robot's view and direct the robot relative to one or more of the landmarks. The integrated UGV control system was evaluated based on its ability to robustly navigate through indoor environments. The system was successfully field tested with QinetiQ North America's TALON UGV and Tactical Robot Controller (TRC), a ruggedized operator control unit (OCU). We found that the proposed system is indeed robust against communication delay and degradation, and provides the operator with steady and reliable control of the UGV in realistic tactical scenarios.

  19. Sensory feedback in prosthetics: a standardized test bench for closed-loop control.

    PubMed

    Dosen, Strahinja; Markovic, Marko; Hartmann, Cornelia; Farina, Dario

    2015-03-01

    Closing the control loop by providing sensory feedback to the user of a prosthesis is an important challenge, with major impact on the future of prosthetics. Developing and comparing closed-loop systems is a difficult task, since there are many different methods and technologies that can be used to implement each component of the system. Here, we present a test bench developed in Matlab Simulink for configuring and testing the closed-loop human control system in standardized settings. The framework comprises a set of connected generic blocks with normalized inputs and outputs, which can be customized by selecting specific implementations from a library of predefined components. The framework is modular and extensible and it can be used to configure, compare and test different closed-loop system prototypes, thereby guiding the development towards an optimal system configuration. The use of the test bench was demonstrated by investigating two important aspects of closed-loop control: performance of different electrotactile feedback interfaces (spatial versus intensity coding) during a pendulum stabilization task and feedforward methods (joystick versus myocontrol) for force control. The first experiment demonstrated that in the case of trained subjects the intensity coding might be superior to spatial coding. In the second experiment, the control of force was rather poor even with a stable and precise control interface (joystick), demonstrating that inherent characteristics of the prosthesis can be an important limiting factor when considering the overall effectiveness of the closed-loop control. The presented test bench is an important instrument for investigating different aspects of human manual control with sensory feedback.

  20. DOE Office of Scientific and Technical Information (OSTI.GOV)

    Kring, C.T.; Varma, V.K.; Jatko, W.B.

    The US Army and Team Crusader (United Defense, Lockheed Martin Armament Systems, etc.) are developing the next generation howitzer, the Crusader. The development program includes an advanced, self-propelled liquid propellant howitzer and a companion resupply vehicle. The resupply vehicle is intended to rendezvous with the howitzer near the battlefront and replenish ammunition, fuel, and other material. The Army has recommended that Crusader incorporate new and innovative technologies to improve performance and safety. One conceptual design proposes a robotic resupply boom on the resupply vehicle to upload supplies to the howitzer. The resupply boom would normally be retracted inside the resupplymore » vehicle during transit. When the two vehicles are within range of the resupply boom, the boom would be extended to a receiving port on the howitzer. In order to reduce exposure to small arms fire or nuclear, biological, and chemical hazards, the crew would remain inside the resupply vehicle during the resupply operation. The process of extending the boom and linking with the receiving port is called docking. A boom operator would be designated to maneuver the boom into contact with the receiving port using a mechanical joystick. The docking operation depends greatly upon the skill of the boom operator to manipulate the boom into docking position. Computer simulations at the National Aeronautics and Space Administration have shown that computer-assisted or autonomous docking can improve the ability of the operator to dock safely and quickly. This document describes the present status of the Crusader Autonomous Docking System (CADS) implemented at Oak Ridge National laboratory (ORNL). The purpose of the CADS project is to determine the feasibility and performance limitations of vision systems to satisfy the autonomous docking requirements for Crusader and conduct a demonstration under controlled conditions.« less

  1. Immersive Earth: Teaching Earth and Space with inexpensive immersive technology

    NASA Astrophysics Data System (ADS)

    Reiff, P. H.; Sumners, C.; Law, C. C.; Handron, K.

    2003-12-01

    In 1995 we pioneered "Space Update", the Digital Library for the rest of us", software that was so simple that a child could use it without a keyboard and yet would allow one-click updating of the daily earth and space science images without the dangers of having an open web browser on display. Thanks to NASA support, it allowed museums and schools to have a powerful exhibit for a tiny price. Over 40,000 disks in our series have been distributed so far to educators and the public. In 2003, with our partners we are again revolutionizing educational technology with a low-cost hardware and software solution to creating and displaying immersive content. Recently selected for funding as part of the REASoN competition, Immersive Earth is a partnership of scientists, museums, educators, and content providers. The hardware consists of a modest projector with a special fisheye lens to be used in an inflatable dome which many schools already have. This, coupled with a modest personal computer, can now easily project images and movies of earth and space, allows training students in 3-D content at a tiny fraction of the cost of a cave or fullscale dome theater. Another low-cost solution is the "Imove" system, where spherical movies can play on a personal computer, with the user changing the viewing direction with a joystick. We were the first to create immersive earth science shows, remain the leader in creating educational content that people want to see. We encourage people with "allsky" images or movies to bring it and see what it looks like inside a dome! Your content could be in our next show!

  2. Comparison of three control methods for an autonomous vehicle

    NASA Astrophysics Data System (ADS)

    Deshpande, Anup; Mathur, Kovid; Hall, Ernest

    2010-01-01

    The desirability and challenge of developing a completely autonomous vehicle and the rising need for more efficient use of energy by automobiles motivate this research- a study for an optimum solution to computer control of energy efficient vehicles. The purpose of this paper is to compare three control methods - mechanical, hydraulic and electric that have been used to convert an experimental all terrain vehicle to drive by wire which would eventually act as a test bed for conducting research on various technologies for autonomous operation. Computer control of basic operations in a vehicle namely steering, braking and speed control have been implemented and will be described in this paper. The output from a 3 axis motion controller is used for this purpose. The motion controller is interfaced with a software program using WSDK (Windows Servo Design Kit) as an intermediate tuning layer for tuning and parameter settings in autonomous operation. The software program is developed in C++. The voltage signal sent to the motion controller can be varied through the control program for desired results in controlling the steering motor, activating the hydraulic brakes and varying the vehicle's speed. The vehicle has been tested for its basic functionality which includes testing of street legal operations and also a 1000 mile test while running in a hybrid mode. The vehicle has also been tested for control when it is interfaced with devices such as a keyboard, joystick and sensors under full autonomous operation. The vehicle is currently being tested in various safety studies and is being used as a test bed for experiments in control courses and research studies. The significance of this research is in providing a greater understanding of conventional driving controls and the possibility of improving automobile safety by removing human error in control of a motor vehicle.

  3. Analysis and prediction of meal motion by EMG signals

    NASA Astrophysics Data System (ADS)

    Horihata, S.; Iwahara, H.; Yano, K.

    2007-12-01

    The lack of carers for senior citizens and physically handicapped persons in our country has now become a huge issue and has created a great need for carer robots. The usual carer robots (many of which have switches or joysticks for their interfaces), however, are neither easy to use it nor very popular. Therefore, haptic devices have been adopted for a human-machine interface that will enable an intuitive operation. At this point, a method is being tested that seeks to prevent a wrong operation from occurring from the user's signals. This method matches motions with EMG signals.

  4. Multimode Radar Signal Processor Integration Facility.

    DTIC Science & Technology

    1983-05-01

    ADDRESS I - T ADDRESS j S DATA BYTE COUNT LEGEND IX ADDRESSING MODE (0 ABSOLUTE I INDEX 1 2 INDEX 2 3 RELATIVE) AD ADDITIVE WRITE (0 REPLACEMENT 1...r I 20 29 2 28 42 62 EE.E70nBE 28 59 2B 2C S D SE 2F 30 31 32 ~~3 0 43 63 9. T U AFWAL-TR-83-1045 data file. To enter a message from the keyboard the...position. In the ENTER mode, interrupts are only generated when the joystick operator depresses a momentary action switch. Each interrupt generated

  5. Development of robotic mobility for infants: rationale and outcomes.

    PubMed

    Larin, Hélène M; Dennis, Carole W; Stansfield, Sharon

    2012-09-01

    To assess the feasibility of a robotic mobility device for infants using alternative control interfaces aimed at promoting early self-initiated mobility, and to assess the effects of a training protocol and robot experience. Observational and pre-post quantitative case studies. Standardised, research laboratory and day-care centres with toys and individuals familiar to infants. Children with and without disabilities, aged 5 months to 3 years. In each study, infants were seated over a Pioneer™ 3-DX mobile robot. Some infants controlled the directional movement of the robot by weight shifting their body on a Nintendo® Wii™ Balance Board (the WeeBot), while others used a modified joystick. Infants participated in five sessions over 2 to 5 weeks. Sessions consisted of administering a 10-minute training protocol preceded and followed by 2 to 3 minutes of free play. One child with motor impairment used a button switch array and a different experimental design. From the videotaped free-play periods, goal-directed behaviours were coded and time in motion was measured. In the training period, a scoring system was developed to measure the infants' driving performance. Preliminary outcomes indicate that infants without disabilities, aged 5 to 10 months, demonstrated significant improvement in driving performance and goal-directed movement using the WeeBot. Infants who used the joystick were less successful on all measures. Results for infants with disabilities using the WeeBot were mixed. Mobile robots offer promise to enhance the development of early self-mobility. Novel types of interfaces, such as the WeeBot, warrant further investigation. Copyright © 2012 Chartered Society of Physiotherapy. Published by Elsevier Ltd. All rights reserved.

  6. Multipurpose surgical robot as a laparoscope assistant.

    PubMed

    Nelson, Carl A; Zhang, Xiaoli; Shah, Bhavin C; Goede, Matthew R; Oleynikov, Dmitry

    2010-07-01

    This study demonstrates the effectiveness of a new, compact surgical robot at improving laparoscope guidance. Currently, the assistant guiding the laparoscope camera tends to be less experienced and requires physical and verbal direction from the surgeon. Human guidance has disadvantages of fatigue and shakiness leading to inconsistency in the field of view. This study investigates whether replacing the assistant with a compact robot can improve the stability of the surgeon's field of view and also reduce crowding at the operating table. A compact robot based on a bevel-geared "spherical mechanism" with 4 degrees of freedom and capable of full dexterity through a 15-mm port was designed and built. The robot was mounted on the standard railing of the operating table and used to manipulate a laparoscope through a supraumbilical port in a porcine model via a joystick controlled externally by a surgeon. The process was videotaped externally via digital video recorder and internally via laparoscope. Robot position data were also recorded within the robot's motion control software. The robot effectively manipulated the laparoscope in all directions to provide a clear and consistent view of liver, small intestine, and spleen. Its range of motion was commensurate with typical motions executed by a human assistant and was well controlled with the joystick. Qualitative analysis of the video suggested that this method of laparoscope guidance provides highly stable imaging during laparoscopic surgery, which was confirmed by robot position data. Because the robot was table-mounted and compact in design, it increased standing room around the operation table and did not interfere with the workspace of other surgical instruments. The study results also suggest that this robotic method may be combined with flexible endoscopes for highly dexterous visualization with more degrees of freedom.

  7. Reaching out towards cannabis: approach-bias in heavy cannabis users predicts changes in cannabis use

    PubMed Central

    Cousijn, Janna; Goudriaan, Anna E; Wiers, Reinout W

    2011-01-01

    Aims Repeated drug exposure can lead to an approach-bias, i.e. the relatively automatically triggered tendencies to approach rather that avoid drug-related stimuli. Our main aim was to study this approach-bias in heavy cannabis users with the newly developed cannabis Approach Avoidance Task (cannabis-AAT) and to investigate the predictive relationship between an approach-bias for cannabis-related materials and levels of cannabis use, craving, and the course of cannabis use. Design, settings and participants Cross-sectional assessment and six-month follow-up in 32 heavy cannabis users and 39 non-using controls. Measurements Approach and avoidance action-tendencies towards cannabis and neutral images were assessed with the cannabis AAT. During the AAT, participants pulled or pushed a joystick in response to image orientation. To generate additional sense of approach or avoidance, pulling the joystick increased picture size while pushing decreased it. Craving was measured pre- and post-test with the multi-factorial Marijuana Craving Questionnaire (MCQ). Cannabis use frequencies and levels of dependence were measured at baseline and after a six-month follow-up. Findings Heavy cannabis users demonstrated an approach-bias for cannabis images, as compared to controls. The approach-bias predicted changes in cannabis use at six-month follow-up. The pre-test MCQ emotionality and expectancy factor were associated negatively with the approach-bias. No effects were found on levels of cannabis dependence. Conclusions Heavy cannabis users with a strong approach-bias for cannabis are more likely to increase their cannabis use. This approach-bias could be used as a predictor of the course of cannabis use to identify individuals at risk from increasing cannabis use. PMID:21518067

  8. Remote atomic force microscopy of microscopic organisms: Technological innovations for hands-on science with middle and high school students

    NASA Astrophysics Data System (ADS)

    Jones, M. G.; Andre, T.; Kubasko, D.; Bokinsky, A.; Tretter, T.; Negishi, A.; Taylor, R.; Superfine, R.

    2004-01-01

    This study examined hands-on experiences in the context of an investigation of viruses and explored how and why hands-on experiences may be effective. We sought to understand whether or not touching and manipulating materials and objects could lead to a deeper, more effective type of knowing than that we obtain from sight or sound alone. Four classes of high school biology students and four classes of seventh graders participated in the study that examined students' use of remote microscopy with a new scientific tool called the nanoManipulator, which enabled them to reach out and touch live viruses inside an atomic force microscope. Half of the students received full haptic (tactile and kinesthetic) feedback from a haptic joystick, whereas half of the students were able to use the haptic joystick to manipulate viruses but the tactile feedback was blocked. Results showed that there were significant gains from pre- to postinstruction across treatment groups for knowledge and attitudes. Students in both treatment groups developed conceptual models of viruses that were more consistent with current scientific research, including a move from a two-dimensional to a three-dimensional understanding of virus morphology. There were significant changes in students' understandings of scale; after instruction, students were more likely to identify examples of nanosized objects and be able to describe the degree to which a human would have to be shrunk to reach the size of a virus. Students who received full-haptic feedback had significantly better attitudes suggesting that the increased sensory feedback and stimulation may have made the experience more engaging and motivating to students.

  9. Strategic Adaptation to Task Characteristics, Incentives, and Individual Differences in Dual-Tasking

    PubMed Central

    Janssen, Christian P.; Brumby, Duncan P.

    2015-01-01

    We investigate how good people are at multitasking by comparing behavior to a prediction of the optimal strategy for dividing attention between two concurrent tasks. In our experiment, 24 participants had to interleave entering digits on a keyboard with controlling a randomly moving cursor with a joystick. The difficulty of the tracking task was systematically varied as a within-subjects factor. Participants were also exposed to different explicit reward functions that varied the relative importance of the tracking task relative to the typing task (between-subjects). Results demonstrate that these changes in task characteristics and monetary incentives, together with individual differences in typing ability, influenced how participants choose to interleave tasks. This change in strategy then affected their performance on each task. A computational cognitive model was used to predict performance for a wide set of alternative strategies for how participants might have possibly interleaved tasks. This allowed for predictions of optimal performance to be derived, given the constraints placed on performance by the task and cognition. A comparison of human behavior with the predicted optimal strategy shows that participants behaved near optimally. Our findings have implications for the design and evaluation of technology for multitasking situations, as consideration should be given to the characteristics of the task, but also to how different users might use technology depending on their individual characteristics and their priorities. PMID:26161851

  10. Evocative gene–environment correlation in the mother–child relationship: A twin study of interpersonal processes

    PubMed Central

    KLAHR, ASHLEA M.; THOMAS, KATHERINE M.; HOPWOOD, CHRISTOPHER J.; KLUMP, KELLY L.; BURT, S. ALEXANDRA

    2014-01-01

    The behavior genetic literature suggests that genetically influenced characteristics of the child elicit specific behaviors from the parent. However, little is known about the processes by which genetically influenced child characteristics evoke parental responses. Interpersonal theory provides a useful framework for identifying reciprocal behavioral processes between children and mothers. The theory posits that, at any given moment, interpersonal behavior varies along the orthogonal dimensions of warmth and control and that the interpersonal behavior of one individual tends to elicit corresponding or contrasting behavior from the other (i.e., warmth elicits warmth, whereas control elicits submission). The current study thus examined these dimensions of interpersonal behavior as they relate to the parent–child relationship in 546 twin families. A computer joystick was used to rate videos of mother–child interactions in real time, yielding information on mother and child levels of warmth and control throughout the interaction. Analyses indicated that maternal control, but not maternal warmth, was influenced by evocative gene–environment correlational processes, such that genetic influences on maternal control and child control were largely overlapping. Moreover, these common genetic influences were present both cross-sectionally and over the course of the interaction. Such findings not only confirm the presence of evocative gene–environment correlational processes in the mother–child relationship but also illuminate at least one of the specific interpersonal behaviors that underlie this evocative process. PMID:23398756

  11. Dynamic clearance measure to evaluate locomotor and perceptuo-motor strategies used for obstacle circumvention in a virtual environment.

    PubMed

    Darekar, Anuja; Lamontagne, Anouk; Fung, Joyce

    2015-04-01

    Circumvention around an obstacle entails a dynamic interaction with the obstacle to maintain a safe clearance. We used a novel mathematical interpolation method based on the modified Shepard's method of Inverse Distance Weighting to compute dynamic clearance that reflected this interaction as well as minimal clearance. This proof-of-principle study included seven young healthy, four post-stroke and four healthy age-matched individuals. A virtual environment designed to assess obstacle circumvention was used to administer a locomotor (walking) and a perceptuo-motor (navigation with a joystick) task. In both tasks, participants were asked to navigate towards a target while avoiding collision with a moving obstacle that approached from either head-on, or 30° left or right. Among young individuals, dynamic clearance did not differ significantly between obstacle approach directions in both tasks. Post-stroke individuals maintained larger and smaller dynamic clearance during the locomotor and the perceptuo-motor task respectively as compared to age-matched controls. Dynamic clearance was larger than minimal distance from the obstacle irrespective of the group, task and obstacle approach direction. Also, in contrast to minimal distance, dynamic clearance can respond differently to different avoidance behaviors. Such a measure can be beneficial in contrasting obstacle avoidance behaviors in different populations with mobility problems. Copyright © 2015 Elsevier B.V. All rights reserved.

  12. Possible End to an Endless Quest? Cognitive Bias Modification for Excessive Multiplayer Online Gamers.

    PubMed

    Rabinovitz, Sharon; Nagar, Maayan

    2015-10-01

    Cognitive biases have previously been recognized as key mechanisms that contribute to the development, maintenance, and relapse of addictive behaviors. The same mechanisms have been recently found in problematic computer gaming. The present study aims to investigate whether excessive massively multiplayer online role-playing gamers (EG) demonstrate an approach bias toward game-related cues compared to neutral stimuli; to test whether these automatic action tendencies can be implicitly modified in a single session training; and to test whether this training affects game urges and game-seeking behavior. EG (n=38) were randomly assigned to a condition in which they were implicitly trained to avoid or to approach gaming cues by pushing or pulling a joystick, using a computerized intervention (cognitive bias modification via the Approach Avoidance Task). EG demonstrated an approach bias for gaming cues compared with neutral, movie cues. Single session training significantly decreased automatic action tendencies to approach gaming cues. These effects occurred outside subjective awareness. Furthermore, approach bias retraining reduced subjective urges and intentions to play, as well as decreased game-seeking behavior. Retraining automatic processes may be beneficial in changing addictive impulses in EG. Yet, large-scale trials and long-term follow-up are warranted. The results extend the application of cognitive bias modification from substance use disorders to behavioral addictions, and specifically to Internet gaming disorder. Theoretical implications are discussed.

  13. Visual enhancements in pick-and-place tasks: Human operators controlling a simulated cylindrical manipulator

    NASA Technical Reports Server (NTRS)

    Kim, Won S.; Tendick, Frank; Stark, Lawrence

    1989-01-01

    A teleoperation simulator was constructed with vector display system, joysticks, and a simulated cylindrical manipulator, in order to quantitatively evaluate various display conditions. The first of two experiments conducted investigated the effects of perspective parameter variations on human operators' pick-and-place performance, using a monoscopic perspective display. The second experiment involved visual enhancements of the monoscopic perspective display, by adding a grid and reference lines, by comparison with visual enhancements of a stereoscopic display; results indicate that stereoscopy generally permits superior pick-and-place performance, but that monoscopy nevertheless allows equivalent performance when defined with appropriate perspective parameter values and adequate visual enhancements.

  14. The efficacy of using human myoelectric signals to control the limbs of robots in space

    NASA Technical Reports Server (NTRS)

    Clark, Jane E.; Phillips, Sally J.

    1988-01-01

    This project was designed to investigate the usefulness of the myoelectric signal as a control in robotics applications. More specifically, the neural patterns associated with human arm and hand actions were studied to determine the efficacy of using these myoelectric signals to control the manipulator arm of a robot. The advantage of this approach to robotic control was the use of well-defined and well-practiced neural patterns already available to the system, as opposed to requiring the human operator to learn new tasks and establish new neural patterns in learning to control a joystick or mechanical coupling device.

  15. Design and implementation of a simple nuclear power plant simulator

    NASA Astrophysics Data System (ADS)

    Miller, William H.

    1983-02-01

    A simple PWR nuclear power plant simulator has been designed and implemented on a minicomputer system. The system is intended for students use in understanding the power operation of a nuclear power plant. A PDP-11 minicomputer calculates reactor parameters in real time, uses a graphics terminal to display the results and a keyboard and joystick for control functions. Plant parameters calculated by the model include the core reactivity (based upon control rod positions, soluble boron concentration and reactivity feedback effects), the total core power, the axial core power distribution, the temperature and pressure in the primary and secondary coolant loops, etc.

  16. Human machine interface to manually drive rhombic like vehicles such as transport casks in ITER

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Lopes, Pedro; Vale, Alberto; Ventura, Rodrigo

    2015-07-01

    The Cask and Plug Remote Handling System (CPRHS) and the respective Cask Transfer System (CTS) are designed to transport activated components between the reactor and the hot cell buildings of ITER during maintenance operations. In nominal operation, the CPRHS/CTS shall operate autonomously under human supervision. However, in some unexpected situations, the automatic mode must be overridden and the vehicle must be remotely guided by a human operator due to the harsh conditions of the environment. The CPRHS/CTS is a rhombic-like vehicle with two independent steerable and drivable wheels along its longitudinal axis, giving it omni-directional capabilities. During manual guidance, themore » human operator has to deal with four degrees of freedom, namely the orientations and speeds of two wheels. This work proposes a Human Machine Interface (HMI) to manage the degrees of freedom and to remotely guide the CPRHS/CTS in ITER taking the most advantages of rhombic like capabilities. Previous work was done to drive each wheel independently, i.e., control the orientation and speed of each wheel independently. The results have shown that the proposed solution is inefficient. The attention of the human operator becomes focused in a single wheel. In addition, the proposed solution cannot assure that the commands accomplish the physical constrains of the vehicle, resulting in slippage or even in clashes. This work proposes a solution that consists in the control of the vehicle looking at the position of its center of mass and its heading in the world frame. The solution is implemented using a rotational disk to control the vehicle heading and a common analogue joystick to control the vector speed of the center of the mass of the vehicle. The number of degrees of freedom reduces to three, i.e., two angles (vehicle heading and the orientation of the vector speed) and a scalar (the magnitude of the speed vector). This is possible using a kinematic model based on the vehicle Instantaneous Center of Rotation (ICR): a geometric approach where, at each time instant, the vehicle describes a circumference (either with a finite or infinite radius). The inverse of the kinematic model transforms the three input parameters of the center of mass into the four parameters for the wheels, preserving the omni-directional capabilities. The solution is implemented and tested using a HMI with a control disk and an analog joystick with two axis. The control disk was specially designed for this solution and implemented using a programmable micro-controller. In the first set of experiments, the HMI communicates with a computer running a simulator of the CPRHS/CTS, with the vehicle kinematics and dynamics, moving in a map of the ITER buildings. In the second set of experiments, the HMI communicates with a scaled prototype of the CPRHS running in a mock-up scenario to obtain more realistic results. Several type of tests were performed to evaluate the usability of the HMI. Different human operators without knowledge neither experience with this interface were invited to test the HMI. The operators had to drive the vehicle from an initial place to a final destination under the following conditions: with a pre-computed path to help guidance, without any path, with the information of the closest obstacles and without any help. The performance was evaluated using the time duration of the operation, the energy required to perform the described path, the risk of collision and, in case of a pre-computed path, the comparison between paths. In addition, each operator tested the HMI several times to evaluate the performance along consecutive trials. (authors)« less

  17. Real-Time Hand Posture Recognition Using a Range Camera

    NASA Astrophysics Data System (ADS)

    Lahamy, Herve

    The basic goal of human computer interaction is to improve the interaction between users and computers by making computers more usable and receptive to the user's needs. Within this context, the use of hand postures in replacement of traditional devices such as keyboards, mice and joysticks is being explored by many researchers. The goal is to interpret human postures via mathematical algorithms. Hand posture recognition has gained popularity in recent years, and could become the future tool for humans to interact with computers or virtual environments. An exhaustive description of the frequently used methods available in literature for hand posture recognition is provided. It focuses on the different types of sensors and data used, the segmentation and tracking methods, the features used to represent the hand postures as well as the classifiers considered in the recognition process. Those methods are usually presented as highly robust with a recognition rate close to 100%. However, a couple of critical points necessary for a successful real-time hand posture recognition system require major improvement. Those points include the features used to represent the hand segment, the number of postures simultaneously recognizable, the invariance of the features with respect to rotation, translation and scale and also the behavior of the classifiers against non-perfect hand segments for example segments including part of the arm or missing part of the palm. A 3D time-of-flight camera named SR4000 has been chosen to develop a new methodology because of its capability to provide in real-time and at high frame rate 3D information on the scene imaged. This sensor has been described and evaluated for its capability for capturing in real-time a moving hand. A new recognition method that uses the 3D information provided by the range camera to recognize hand postures has been proposed. The different steps of this methodology including the segmentation, the tracking, the hand modeling and finally the recognition process have been described and evaluated extensively. In addition, the performance of this method has been analyzed against several existing hand posture recognition techniques found in literature. The proposed system is able to recognize with an overall recognition rate of 98% and in real-time 18 out the 33 postures of the American sign language alphabet. This recognition is translation, rotation and scale invariant.

  18. Structural Differences in Gray Matter between Glider Pilots and Non-Pilots. A Voxel-Based Morphometry Study

    PubMed Central

    Ahamed, Tosif; Kawanabe, Motoaki; Ishii, Shin; Callan, Daniel E.

    2014-01-01

    Glider flying is a unique skill that requires pilots to control an aircraft at high speeds in three dimensions and amidst frequent full-body rotations. In the present study, we investigated the neural correlates of flying a glider using voxel-based morphometry. The comparison between gray matter densities of 15 glider pilots and a control group of 15 non-pilots exhibited significant gray matter density increases in left ventral premotor cortex, anterior cingulate cortex, and the supplementary eye field. We posit that the identified regions might be associated with cognitive and motor processes related to flying, such as joystick control, visuo-vestibular interaction, and oculomotor control. PMID:25506339

  19. Education Outreach at M.I.T. Plasma Science and Fusion Center

    NASA Astrophysics Data System (ADS)

    Rivenberg, P.; Censabella, V.

    2000-10-01

    At the MIT PSFC student and staff volunteers work together to increase the public's knowledge of fusion and plasma-related experiments. Seeking to generate excitement about science, engineering and mathematics, the PSFC holds a number of outreach activities throughout the year, including Middle and High School Outreach Days and the Mr. Magnet program. During the past year, in collaboration with the MIT Museum, the PSFC reprogrammed their C-Mod, Jr Video Game to be operated via the keyboard instead of joysticks. The game will eventually be available on the web and on disc. The PSFC maintains a Home Page on the World Wide Web, which can be reached at http://www.psfc.mit.edu.

  20. Widened photonic functionality of asymmetric high-index contrast/photonic crystal gratings

    NASA Astrophysics Data System (ADS)

    Nguyen, Hai Son; Dubois, Florian; Letartre, Xavier; Leclercq, Jean-Louis; Seassal, Christian; Viktorovitch, Pierre

    2016-03-01

    In this presentation we emphasize that, within the variety of parameters usable for the design of HCGs, the transverse (vertical) symmetry properties of HCGs provide a power-full joystick for the dispersion engineering of guided mode resonances. We concentrate on asymmetric HCGs designed to accommodate guided mode resonances with ultra-flat zero-curvature dispersion characteristics (or photons with ultra-heavy effective mass), as well as with Dirac cone shaped linear dispersion characteristics. Examples of the great potential of this family of asymmetric HCGs will include the development of a platform for polaritonic devices and the production of micro-lasers particularly suited for hybrid III-V / silicon heterogeneous photonic integration, along CMOS compatible technological schemes.

  1. Real-time head movement system and embedded Linux implementation for the control of power wheelchairs.

    PubMed

    Nguyen, H T; King, L M; Knight, G

    2004-01-01

    Mobility has become very important for our quality of life. A loss of mobility due to an injury is usually accompanied by a loss of self-confidence. For many individuals, independent mobility is an important aspect of self-esteem. Head movement is a natural form of pointing and can be used to directly replace the joystick whilst still allowing for similar control. Through the use of embedded LINUX and artificial intelligence, a hands-free head movement wheelchair controller has been designed and implemented successfully. This system provides for severely disabled users an effective power wheelchair control method with improved posture, ease of use and attractiveness.

  2. Use of force feedback to enhance graphical user interfaces

    NASA Astrophysics Data System (ADS)

    Rosenberg, Louis B.; Brave, Scott

    1996-04-01

    This project focuses on the use of force feedback sensations to enhance user interaction with standard graphical user interface paradigms. While typical joystick and mouse devices are input-only, force feedback controllers allow physical sensations to be reflected to a user. Tasks that require users to position a cursor on a given target can be enhanced by applying physical forces to the user that aid in targeting. For example, an attractive force field implemented at the location of a graphical icon can greatly facilitate target acquisition and selection of the icon. It has been shown that force feedback can enhance a users ability to perform basic functions within graphical user interfaces.

  3. Lana chimpanzee learns to count by 'numath' - A summary of a videotaped experimental report

    NASA Technical Reports Server (NTRS)

    Rumbaugh, Duane M.; Hopkins, William D.; Washburn, David A.; Savage-Rumbaugh, E. Sue

    1989-01-01

    Computerized training programs whereby an adult female chimpanzee learned to use a joystick to remove from a screen the number of boxes appropriate to the value of a randomly selected Arabic numeral 1, 2, or 3, are studied. Initial training provided a variety of cues, both numeric and otherwise, to support correct performance. In the final test, the ape was correct on over 80 percent of trials in which there was no residual feedback of intratrial events and where only her memory of those events could provide the cue to indicate that she had removed boxes in accordance with the value of the target numbers and should terminate the trial.

  4. Structural Differences in Gray Matter between Glider Pilots and Non-Pilots. A Voxel-Based Morphometry Study.

    PubMed

    Ahamed, Tosif; Kawanabe, Motoaki; Ishii, Shin; Callan, Daniel E

    2014-01-01

    Glider flying is a unique skill that requires pilots to control an aircraft at high speeds in three dimensions and amidst frequent full-body rotations. In the present study, we investigated the neural correlates of flying a glider using voxel-based morphometry. The comparison between gray matter densities of 15 glider pilots and a control group of 15 non-pilots exhibited significant gray matter density increases in left ventral premotor cortex, anterior cingulate cortex, and the supplementary eye field. We posit that the identified regions might be associated with cognitive and motor processes related to flying, such as joystick control, visuo-vestibular interaction, and oculomotor control.

  5. Sensing interactions in the microworld with optical tweezers

    NASA Astrophysics Data System (ADS)

    Pacoret, Cécile; Bowman, Richard; Gibson, Graham; Sinan, Haliyo D.; Bergander, Arvid; Carberry, David; Régnier, Stéphane; Padgett, Miles

    2009-08-01

    Optical Tweezers have become a widespread tool in Cell Biology, microengineering and other fields requiring delicate micromanipulation. But for those sensitive tasks, it remains difficult to handle objects without damaging them. As the precision in position and force measurement increase, the richness of information cannot be fully exploited with simple interfaces such as a mouse or a common joystick. For this reason, we propose a haptic force-feedback optical tweezer command and a force-feedback system controlled by one hand. The system combines accurate force measurement using a fast camera and the coupling of these measured forces with a human operator. The overall transparency allows even the feeling of the Brownian motion.

  6. Feedback from video for virtual reality Navigation

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Tsap, L V

    2000-10-27

    Important preconditions for wide acceptance of virtual reality (VR) systems include their comfort, ease and naturalness to use. Most existing trackers super from discomfort-related issues. For example, body-based trackers (hand controllers, joysticks, helmet attachments, etc.) restrict spontaneity and naturalness of motion, while ground-based devices (e.g., hand controllers) limit the workspace by literally binding an operator to the ground. There are similar problems with controls. This paper describes using real-time video with registered depth information (from a commercially available camera) for virtual reality navigation. Camera-based setup can replace cumbersome trackers. The method includes selective depth processing for increased speed, and amore » robust skin-color segmentation for accounting illumination variations.« less

  7. The push and pull of grief: Approach and avoidance in bereavement.

    PubMed

    Maccallum, Fiona; Sawday, Simon; Rinck, Mike; Bryant, Richard A

    2015-09-01

    Prolonged Grief (PG) is recognized as a post-bereavement syndrome that is associated with significant impairment. Although approach and avoidance tendencies have both been hypothesized to play key roles in maintaining PG symptoms, understanding of these relationships has been limited by a reliance on self-report methodology. This study applies an experimental paradigm to simultaneously investigate the relationship between PG severity and approach-avoidance behavioral tendencies. Fifty-five bereaved individuals with and without PG completed a behavioral measure of approach and avoidance responding in which they pulled or pushed a joystick in response to grief-related, positive, negative and neutral images that appeared on a computer screen. Concurrent visual feedback created the illusion that the images were either approaching or receding from the participant. Half of the participants also received a prime designed to activate their grief prior to the task. Irrespective of prime condition, PG participants pulled grief-related images more quickly than they pushed them. This difference was not observed in response to non-grief related images. Non PG participants showed no difference in their reaction times to grief-stimuli. This study was undertaken in a nonclinical setting and the majority of participants had lost a loved one due to chronic illness. Future research with treatment-seeking populations and sudden loss will be needed to explore the generalizability of the findings. The findings from this study provide preliminary evidence supporting models of PG that integrate approach and avoidance tendencies. Copyright © 2015 Elsevier Ltd. All rights reserved.

  8. Decoding Trajectories from Posterior Parietal Cortex Ensembles

    PubMed Central

    Mulliken, Grant H.; Musallam, Sam; Andersen, Richard A.

    2009-01-01

    High-level cognitive signals in the posterior parietal cortex (PPC) have previously been used to decode the intended endpoint of a reach, providing the first evidence that PPC can be used for direct control of a neural prosthesis (Musallam et al., 2004). Here we expand on this work by showing that PPC neural activity can be harnessed to estimate not only the endpoint but also to continuously control the trajectory of an end effector. Specifically, we trained two monkeys to use a joystick to guide a cursor on a computer screen to peripheral target locations while maintaining central ocular fixation. We found that we could accurately reconstruct the trajectory of the cursor using a relatively small ensemble of simultaneously recorded PPC neurons. Using a goal-based Kalman filter that incorporates target information into the state-space, we showed that the decoded estimate of cursor position could be significantly improved. Finally, we tested whether we could decode trajectories during closed-loop brain control sessions, in which the real-time position of the cursor was determined solely by a monkey’s neural activity in PPC. The monkey learned to perform brain control trajectories at 80% success rate(for 8 targets) after just 4–5 sessions. This improvement in behavioral performance was accompanied by a corresponding enhancement in neural tuning properties (i.e., increased tuning depth and coverage of encoding parameter space) as well as an increase in off-line decoding performance of the PPC ensemble. PMID:19036985

  9. Testing geoscience data visualization systems for geological mapping and training

    NASA Astrophysics Data System (ADS)

    Head, J. W.; Huffman, J. N.; Forsberg, A. S.; Hurwitz, D. M.; Basilevsky, A. T.; Ivanov, M. A.; Dickson, J. L.; Senthil Kumar, P.

    2008-09-01

    Traditional methods of planetary geological mapping have relied on photographic hard copy and light-table tracing and mapping. In the last several decades this has given way to the availability and analysis of multiple digital data sets, and programs and platforms that permit the viewing and manipulation of multiple annotated layers of relevant information. This has revolutionized the ability to incorporate important new data into the planetary mapping process at all scales. Information on these developments and approaches can be obtained at http://astrogeology.usgs. gov/ Technology/. The processes is aided by Geographic Information Systems (GIS) (see http://astrogeology. usgs.gov/Technology/) and excellent analysis packages (such as ArcGIS) that permit co-registration, rapid viewing, and analysis of multiple data sets on desktop displays (see http://astrogeology.usgs.gov/Projects/ webgis/). We are currently investigating new technological developments in computer visualization and analysis in order to assess their importance and utility in planetary geological analysis and mapping. Last year we reported on the range of technologies available and on our application of these to various problems in planetary mapping. In this contribution we focus on the application of these techniques and tools to Venus geological mapping at the 1:5M quadrangle scale. In our current Venus mapping projects we have utilized and tested the various platforms to understand their capabilities and assess their usefulness in defining units, establishing stratigraphic relationships, mapping structures, reaching consensus on interpretations and producing map products. We are specifically assessing how computer visualization display qualities (e.g., level of immersion, stereoscopic vs. monoscopic viewing, field of view, large vs. small display size, etc.) influence performance on scientific analysis and geological mapping. We have been exploring four different environments: 1) conventional desktops (DT), 2) semi-immersive Fishtank VR (FT) (i.e., a conventional desktop with head-tracked stereo and 6DOF input), 3) tiled wall displays (TW), and 4) fully immersive virtual reality (IVR) (e.g., "Cave Automatic Virtual Environment", or Cave system). Formal studies demonstrate that fully immersive Cave environments are superior to desktop systems for many tasks. There is still much to learn and understand, however, about how the varying degrees of immersive displays affect task performance. For example, in using a 1280x1024 desktop monitor to explore an image, the mapper wastes a lot of time in image zooming/panning to balance the analysis-driven need for both detail as well as context. Therefore, we have spent a considerable amount of time exploring higher-resolution media, such as an IBM Bertha display 3840x2400 or a tiled wall with multiple projectors. We have found through over a year of weekly meetings and assessment that they definitely improve the efficiency of analysis and mapping. Here we outline briefly the nature of the major systems and our initial assessment of these in 1:5M Scale NASA-USGS Venus Geological Mapping Program (http://astrogeology.usgs. gov/Projects/PlanetaryMapping/MapStatus/VenusStatus/V enus_Status.html). 1. Immersive Virtual Reality (Cave): ADVISER System Description: Our Cave system is an 8'x8'x8' cube with four projection surfaces (three walls and the floor). Four linux machines (identical in performance to the desktop machine) provide data for the Cave. Users utilize a handheld 3D tracked input device to navigate. Our 3D input device has a joystick and is simple to use. To navigate, the user simply points in the direction he/she wants to fly and pushes the joystick forward or backward to move relative to that direction. The user can push the joystick to the left and right to rotate his/her position in the virtual world. A collision detection algorithm is used to prevent the user from going underneath the surface. We have developed ADVISER (ADvanced VIsualization for Solar system Exploration) [1,2] as a tool for taking planetary geologists virtually "into the field" in the IVR Cave environment in support of several scientific themes and have assessed its application to geological mapping of Venus. ADVISER aims to create a field experience by integrating multiple data sources and presenting them as a unified environment to the scientist. Additionally, we have developed a virtual field kit, tailored to supporting research tasks dictated by scientific and mapping themes. Technically, ADVISER renders high-resolution topographic and image datasets (8192x8192 samples) in stereo at interactive frame-rates (25+ frames-per-second). The system is based on a state-of-the-art terrain rendering system and is highly interactive; for example, vertical exaggeration, lighting geometry, image contrast, and contour lines can be modified by the user in real time. High-resolution image data can be overlaid on the terrain and other data can be rendered in this context. A detailed description and case studies of ADVISER are available.

  10. MAT - MULTI-ATTRIBUTE TASK BATTERY FOR HUMAN OPERATOR WORKLOAD AND STRATEGIC BEHAVIOR RESEARCH

    NASA Technical Reports Server (NTRS)

    Comstock, J. R.

    1994-01-01

    MAT, a Multi-Attribute Task battery, gives the researcher the capability of performing multi-task workload and performance experiments. The battery provides a benchmark set of tasks for use in a wide range of laboratory studies of operator performance and workload. MAT incorporates tasks analogous to activities that aircraft crew members perform in flight, while providing a high degree of experiment control, performance data on each subtask, and freedom to use non-pilot test subjects. The MAT battery primary display is composed of four separate task windows which are as follows: a monitoring task window which includes gauges and warning lights, a tracking task window for the demands of manual control, a communication task window to simulate air traffic control communications, and a resource management task window which permits maintaining target levels on a fuel management task. In addition, a scheduling task window gives the researcher information about future task demands. The battery also provides the option of manual or automated control of tasks. The task generates performance data for each subtask. The task battery may be paused and onscreen workload rating scales presented to the subject. The MAT battery was designed to use a serially linked second computer to generate the voice messages for the Communications task. The MATREMX program and support files, which are included in the MAT package, were designed to work with the Heath Voice Card (Model HV-2000, available through the Heath Company, Benton Harbor, Michigan 49022); however, the MATREMX program and support files may easily be modified to work with other voice synthesizer or digitizer cards. The MAT battery task computer may also be used independent of the voice computer if no computer synthesized voice messages are desired or if some other method of presenting auditory messages is devised. MAT is written in QuickBasic and assembly language for IBM PC series and compatible computers running MS-DOS. The code in MAT is written for Microsoft QuickBasic 4.5 and Microsoft Macro Assembler 5.1. This package requires a joystick and EGA or VGA color graphics. An 80286, 386, or 486 processor machine is highly recommended. The standard distribution medium for MAT is a 5.25 inch 360K MS-DOS format diskette. The files are compressed using the PKZIP file compression utility. PKUNZIP is included on the distribution diskette. MAT was developed in 1992. IBM PC is a registered trademark of International Business Machines. MS-DOS, Microsoft QuickBasic, and Microsoft Macro Assembler are registered trademarks of Microsoft Corporation. PKZIP and PKUNZIP are registered trademarks of PKWare, Inc.

  11. Post-stroke unilateral spatial neglect: virtual reality-based navigation and detection tasks reveal lateralized and non-lateralized deficits in tasks of varying perceptual and cognitive demands.

    PubMed

    Ogourtsova, Tatiana; Archambault, Philippe S; Lamontagne, Anouk

    2018-04-23

    Unilateral spatial neglect (USN), a highly prevalent and disabling post-stroke impairment, has been shown to affect the recovery of locomotor and navigation skills needed for community mobility. We recently found that USN alters goal-directed locomotion in conditions of different cognitive/perceptual demands. However, sensorimotor post-stroke dysfunction (e.g. decreased walking speed) could have influenced the results. Analogous to a previously used goal-directed locomotor paradigm, a seated, joystick-driven navigation experiment, minimizing locomotor demands, was employed in individuals with and without post-stroke USN (USN+ and USN-, respectively) and healthy controls (HC). Participants (n = 15 per group) performed a seated, joystick-driven navigation and detection time task to targets 7 m away at 0°, ±15°/30° in actual (visually-guided), remembered (memory-guided) and shifting (visually-guided with representational updating component) conditions while immersed in a 3D virtual reality environment. Greater end-point mediolateral errors to left-sided targets (remembered and shifting conditions) and overall lengthier onsets in reorientation strategy (shifting condition) were found for USN+ vs. USN- and vs. HC (p < 0.05). USN+ individuals mostly overshot left targets (- 15°/- 30°). Greater delays in detection time for target locations across the visual spectrum (left, middle and right) were found in USN+ vs. USN- and HC groups (p < 0.05). USN-related attentional-perceptual deficits alter navigation abilities in memory-guided and shifting conditions, independently of post-stroke locomotor deficits. Lateralized and non-lateralized deficits in object detection are found. The employed paradigm could be considered in the design and development of sensitive and functional assessment methods for neglect; thereby addressing the drawbacks of currently used traditional paper-and-pencil tools.

  12. Motion-Capture-Enabled Software for Gestural Control of 3D Models

    NASA Technical Reports Server (NTRS)

    Norris, Jeffrey S.; Luo, Victor; Crockett, Thomas M.; Shams, Khawaja S.; Powell, Mark W.; Valderrama, Anthony

    2012-01-01

    Current state-of-the-art systems use general-purpose input devices such as a keyboard, mouse, or joystick that map to tasks in unintuitive ways. This software enables a person to control intuitively the position, size, and orientation of synthetic objects in a 3D virtual environment. It makes possible the simultaneous control of the 3D position, scale, and orientation of 3D objects using natural gestures. Enabling the control of 3D objects using a commercial motion-capture system allows for natural mapping of the many degrees of freedom of the human body to the manipulation of the 3D objects. It reduces training time for this kind of task, and eliminates the need to create an expensive, special-purpose controller.

  13. Curiosity: How to Boldly Go...

    NASA Technical Reports Server (NTRS)

    Pyrzak, Guy

    2013-01-01

    Operating a one-ton rover on the surface of Mars requires more than just a joystick and an experiment. With 10 science instruments, 17 cameras, a radioisotope thermoelectric generator and lasers, Curiosity is the largest and most complex rover NASA has sent to Mars. Combined with a 1 way light time of 4 to 20 minutes and a distributed international science and engineering team, it takes a lot of work to operate this mega-rover. The Mars Science Lab's operations team has developed an organization and process that maximizes science return and safety of the spacecraft. These are the voyages of the rover Curiosity, its 2 year mission, to determine the habitability of Gale Crater, to understand the role of water, to study the climate and geology of Mars.

  14. Dual arm coordination and control

    NASA Technical Reports Server (NTRS)

    Hayati, Samad; Tso, Kam; Lee, Thomas

    1989-01-01

    A generalized master/slave technique and experimental results for coordinated control of two arms rigidly grasping an object is described. An interactive program has been developed to allow a user the flexibility to select appropriate control modes for a given experiment. This interface allows for control gain adjustments. The results of several experiments performed on this system to demonstrate its capabilities such as transporting an object with or without induced internal forces and movement of a constrained object are offered. The system is further developed to achieve a so-called shared control mode in which an operator specifies the free motion trajectory for a point on the object of manipulation via a joystick while the autonomous control system is used for coordination and control of the arms.

  15. Thumb-actuated two-axis controller

    NASA Technical Reports Server (NTRS)

    Hollow, R. H. (Inventor)

    1986-01-01

    A two axis joystick controller is described. It produces at least one output signal in relation to pivotal displacement of a member with respect to an intersection of the two axes. The member is pivotally movable on a support with respect to the two axes. The support has a centrally disposed aperture. A light source is mounted on the pivotally movable member above the aperture to direct light through the aperture. A light sensor is mounted below the aperture in the support at the intersection of the two axes to receive the light from the light source directed through the aperture. The light sensor produces at least one output signal related to a location on the sensor at which the light from the light source strikes the sensor.

  16. Web-based telerehabilitation for the upper extremity after stroke.

    PubMed

    Reinkensmeyer, David J; Pang, Clifton T; Nessler, Jeff A; Painter, Christopher C

    2002-06-01

    Stroke is a leading cause of disability in the United States and yet little technology is currently available for individuals with stroke to practice and monitor rehabilitation therapy on their own. This paper provides a detailed design description of a telerehabilitation system for arm and hand therapy following stroke. The system consists of a Web-based library of status tests, therapy games, and progress charts, and can be used with a variety of input devices, including a low-cost force-feedback joystick capable of assisting or resisting in movement. Data from home-based usage by a chronic stroke subject are presented that demonstrate the feasibility of using the system to direct a therapy program, mechanically assist in movement, and track improvements in movement ability.

  17. Development of a multipurpose hand controller for JEMRMS

    NASA Technical Reports Server (NTRS)

    Matsuhira, Nobuto; Iikura, Shoichi; Asakura, Makoto; Shinomiya, Yasuo

    1990-01-01

    A prototype multipurpose hand controller for the JEMRMS (Japanese Experiment Module Remote Manipulator System) was developed. The hand controller (H/C) is an orthogonal type, with 6 degrees of freedom (DOF) and small size. The orthogonal type H/C is very simple for coordinate transformations and can easily control any type of manipulators. In fact, the JEMRMS is planned to have two manipulators controlled by a common H/C at this stage. The H/C was able to be used as a rate control joystick and a force reflection master arm, using an experimental 6 DOF manipulator. Good maneuverability was confirmed in the verification test. The orthogonal type H/C is suitable for use as a common H/C for the two manipulators of the JEMRMS.

  18. Coordinated joint motion control system with position error correction

    DOEpatents

    Danko, George [Reno, NV

    2011-11-22

    Disclosed are an articulated hydraulic machine supporting, control system and control method for same. The articulated hydraulic machine has an end effector for performing useful work. The control system is capable of controlling the end effector for automated movement along a preselected trajectory. The control system has a position error correction system to correct discrepancies between an actual end effector trajectory and a desired end effector trajectory. The correction system can employ one or more absolute position signals provided by one or more acceleration sensors supported by one or more movable machine elements. Good trajectory positioning and repeatability can be obtained. A two-joystick controller system is enabled, which can in some cases facilitate the operator's task and enhance their work quality and productivity.

  19. Multi-degree of freedom joystick for virtual reality simulation.

    PubMed

    Head, M J; Nelson, C A; Siu, K C

    2013-11-01

    A modular control interface and simulated virtual reality environment were designed and created in order to determine how the kinematic architecture of a control interface affects minimally invasive surgery training. A user is able to selectively determine the kinematic configuration of an input device (number, type and location of degrees of freedom) for a specific surgical simulation through the use of modular joints and constraint components. Furthermore, passive locking was designed and implemented through the use of inflated latex tubing around rotational joints in order to allow a user to step away from a simulation without unwanted tool motion. It is believed that these features will facilitate improved simulation of a variety of surgical procedures and, thus, improve surgical skills training.

  20. Using Self-Reliance Factors to Decide How to Share Control Between Human Powered Wheelchair Drivers and Ultrasonic Sensors.

    PubMed

    Sanders, David A

    2017-08-01

    A shared-control scheme for a powered wheelchair is presented. The wheelchair can be operated by a wheelchair driver using a joystick, or directed by a sensor system, or control can be combined between them. The wheelchair system can modify direction depending on the local environment. Sharing the control allows a disabled wheelchair driver to drive safely and efficiently. The controller automatically establishes the control gains for the sensor system and the human driver by calculating a self-reliance factor for the wheelchair driver. The sensor system can influence the motion of the wheelchair to compensate for some deficiency in a disabled driver. Practical tests validate the proposed techniques and designs.

  1. Using a smart wheelchair as a gaming device for floor-projected games: a mixed-reality environment for training powered-wheelchair driving skills.

    PubMed

    Secoli, R; Zondervan, D; Reinkensmeyer, D

    2012-01-01

    For children with a severe disability, such as can arise from cerebral palsy, becoming independent in mobility is a critical goal. Currently, however, driver's training for powered wheelchair use is labor intensive, requiring hand-over-hand assistance from a skilled therapist to keep the trainee safe. This paper describes the design of a mixed reality environment for semi-autonomous training of wheelchair driving skills. In this system, the wheelchair is used as the gaming input device, and users train driving skills by maneuvering through floor-projected games created with a multi-projector system and a multi-camera tracking system. A force feedback joystick assists in steering and enhances safety.

  2. Coordinated joint motion control system with position error correction

    DOEpatents

    Danko, George L.

    2016-04-05

    Disclosed are an articulated hydraulic machine supporting, control system and control method for same. The articulated hydraulic machine has an end effector for performing useful work. The control system is capable of controlling the end effector for automated movement along a preselected trajectory. The control system has a position error correction system to correct discrepancies between an actual end effector trajectory and a desired end effector trajectory. The correction system can employ one or more absolute position signals provided by one or more acceleration sensors supported by one or more movable machine elements. Good trajectory positioning and repeatability can be obtained. A two joystick controller system is enabled, which can in some cases facilitate the operator's task and enhance their work quality and productivity.

  3. The embodiment of success and failure as forward versus backward movements.

    PubMed

    Robinson, Michael D; Fetterman, Adam K

    2015-01-01

    People often speak of success (e.g., "advance") and failure (e.g., "setback") as if they were forward versus backward movements through space. Two experiments sought to examine whether grounded associations of this type influence motor behavior. In Experiment 1, participants categorized success versus failure words by moving a joystick forward or backward. Failure categorizations were faster when moving backward, whereas success categorizations were faster when moving forward. Experiment 2 removed the requirement to categorize stimuli and used a word rehearsal task instead. Even without Experiment 1's response procedures, a similar cross-over interaction was obtained (e.g., failure memorizations sped backward movements relative to forward ones). The findings are novel yet consistent with theories of embodied cognition and self-regulation.

  4. A physical control interface with proprioceptive feedback and multiple degrees of freedom

    NASA Technical Reports Server (NTRS)

    Creasey, G. H.; Gow, D.; Sloan, Y.; Meadows, B.

    1991-01-01

    The use of the drug thalidomide by pregnant mothers in Britain resulted in a variety of deformities including the birth of children having no arms. Such children were provided with powered artificial arms with up to five degrees of freedom simultaneously controlled in real time by shoulder movement. The physiological sense of proprioception was extended from the user into the device, reducing the need for visual feedback and conscious control. With the banning of thalidomide, this technique fell into disuse but it is now being re-examined as a control mechanism for other artificial limbs and it may have other medical applications to allow patients to control formerly paralyzed limbs moved by electrical stimulation. It may also have commercial applications in robotic manipulation or physical interaction with virtual environments. To allow it to be investigated further, the original pneumatic control system has recently been converted to an electrical analogue to allow interfacing to electronic and computer-assisted systems. A harness incorporates force-sensitive resistors and linear potentiomenters for sensing position and force at the interface with the skin, and miniature electric motors and lead screws for feeding back to the user the position of the robotic arm and the forces applied to it. In the present system, control is applied to four degrees of freedom using elevation/depression and protraction/reaction of each shoulder so that each collar bone emulates a joystick. However, both electrical and mechanical components have been built in modular form to allow rapid replication and testing of a variety of force and position control strategies.

  5. Nintendo related injuries and other problems: review.

    PubMed

    Jalink, Maarten B; Heineman, Erik; Pierie, Jean-Pierre E N; ten Cate Hoedemaker, Henk O

    2014-12-16

    To identify all reported cases of injury and other problems caused by using a Nintendo video gaming system. Review. Search of PubMed and Embase in June 2014 for reports on injuries and other problems caused by using a Nintendo gaming system. Most of the 38 articles identified were case reports or case series. Injuries and problems ranged from neurological and psychological to surgical. Traditional controllers with buttons were associated with tendinitis of the extensor of the thumb. The joystick on the Nintendo 64 controller was linked to palmar ulceration. The motion sensitive Wii remote was associated with musculoskeletal problems and various traumas. Most problems are mild and prevalence is low. The described injuries were related to the way the games are controlled, which varies according to the video game console. © Jalink et al 2014.

  6. Considerations for human-machine interfaces in tele-operations

    NASA Technical Reports Server (NTRS)

    Newport, Curt

    1991-01-01

    Numerous factors impact on the efficiency of tele-operative manipulative work. Generally, these are related to the physical environment of the tele-operator and how he interfaces with robotic control consoles. The capabilities of the operator can be influenced by considerations such as temperature, eye strain, body fatigue, and boredom created by repetitive work tasks. In addition, the successful combination of man and machine will, in part, be determined by the configuration of the visual and physical interfaces available to the teleoperator. The design and operation of system components such as full-scale and mini-master manipulator controllers, servo joysticks, and video monitors will have a direct impact on operational efficiency. As a result, the local environment and the interaction of the operator with the robotic control console have a substantial effect on mission productivity.

  7. Hitts Law? A test of the relationship between information load and movement precision

    NASA Technical Reports Server (NTRS)

    Zaleski, M.; Moray, N.

    1986-01-01

    Recent technological developments have made viable a man-machine interface heavily dependent on graphics and pointing devices. This has led to new interest in classical reaction and movement time work by Human Factors specialists. Two experiments were designed and run to test the dependence of target capture time on information load (Hitt's Law) and movement precision (Fitts' Law). The proposed model linearly combines Hitt's and Fitts' results into a combination law which then might be called Hitts' Law. Subjects were required to react to stimuli by manipulating a joystick so as to cause a cursor to capture a target on a CRT screen. Response entropy and the relative precision of the capture movement were crossed in a factorial design and data obtained that were found to support the model.

  8. Development of real-time motion capture system for 3D on-line games linked with virtual character

    NASA Astrophysics Data System (ADS)

    Kim, Jong Hyeong; Ryu, Young Kee; Cho, Hyung Suck

    2004-10-01

    Motion tracking method is being issued as essential part of the entertainment, medical, sports, education and industry with the development of 3-D virtual reality. Virtual human character in the digital animation and game application has been controlled by interfacing devices; mouse, joysticks, midi-slider, and so on. Those devices could not enable virtual human character to move smoothly and naturally. Furthermore, high-end human motion capture systems in commercial market are expensive and complicated. In this paper, we proposed a practical and fast motion capturing system consisting of optic sensors, and linked the data with 3-D game character with real time. The prototype experiment setup is successfully applied to a boxing game which requires very fast movement of human character.

  9. The Embodiment of Success and Failure as Forward versus Backward Movements

    PubMed Central

    Robinson, Michael D.; Fetterman, Adam K.

    2015-01-01

    People often speak of success (e.g., “advance”) and failure (e.g., “setback”) as if they were forward versus backward movements through space. Two experiments sought to examine whether grounded associations of this type influence motor behavior. In Experiment 1, participants categorized success versus failure words by moving a joystick forward or backward. Failure categorizations were faster when moving backward, whereas success categorizations were faster when moving forward. Experiment 2 removed the requirement to categorize stimuli and used a word rehearsal task instead. Even without Experiment 1’s response procedures, a similar cross-over interaction was obtained (e.g., failure memorizations sped backward movements relative to forward ones). The findings are novel yet consistent with theories of embodied cognition and self-regulation. PMID:25658923

  10. Home-based Computer Assisted Arm Rehabilitation (hCAAR) robotic device for upper limb exercise after stroke: results of a feasibility study in home setting.

    PubMed

    Sivan, Manoj; Gallagher, Justin; Makower, Sophie; Keeling, David; Bhakta, Bipin; O'Connor, Rory J; Levesley, Martin

    2014-12-12

    Home-based robotic technologies may offer the possibility of self-directed upper limb exercise after stroke as a means of increasing the intensity of rehabilitation treatment. The current literature has a paucity of robotic devices that have been tested in a home environment. The aim of this research project was to evaluate a robotic device Home-based Computer Assisted Arm Rehabilitation (hCAAR) that can be used independently at home by stroke survivors with upper limb weakness. hCAAR device comprises of a joystick handle moved by the weak upper limb to perform tasks on the computer screen. The device provides assistance to the movements depending on users ability. Nineteen participants (stroke survivors with upper limb weakness) were recruited. Outcome measures performed at baseline (A0), at end of 8-weeks of hCAAR use (A1) and 1 month after end of hCAAR use (A2) were: Optotrak kinematic variables, Fugl Meyer Upper Extremity motor subscale (FM-UE), Action Research Arm Test (ARAT), Medical Research Council (MRC) and Modified Ashworth Scale (MAS), Chedoke Arm and Hand Activity Inventory (CAHAI) and ABILHAND. Two participants were unable to use hCAAR: one due to severe paresis and the other due to personal problems. The remaining 17 participants were able to use the device independently in their home setting. No serious adverse events were reported. The median usage time was 433 minutes (IQR 250 - 791 min). A statistically significant improvement was observed in the kinematic and clinical outcomes at A1. The median gain in the scores at A1 were by: movement time 19%, path length 15% and jerk 19%, FM-UE 1 point, total MAS 1.5 point, total MRC 2 points, ARAT 3 points, CAHAI 5.5 points and ABILHAND 3 points. Three participants showed clinically significant improvement in all the clinical outcomes. The hCAAR feasibility study is the first clinical study of its kind reported in the current literature; in this study, 17 participants used the robotic device independently for eight weeks in their own homes with minimal supervision from healthcare professionals. Statistically significant improvements were observed in the kinematic and clinical outcomes in the study.

  11. Evaluation of head orientation and neck muscle EMG signals as three-dimensional command sources.

    PubMed

    Williams, Matthew R; Kirsch, Robert F

    2015-03-05

    High cervical spinal cord injuries result in significant functional impairments and affect both the injured individual as well as their family and care givers. To help restore function to these individuals, multiple user interfaces are available to enable command and control of external devices. However, little work has been performed to assess the 3D performance of these interfaces. We investigated the performance of eight human subjects in using three user interfaces (head orientation, EMG from muscles of the head and neck, and a three-axis joystick) to command the endpoint position of a multi-axis robotic arm within a 3D workspace to perform a novel out-to-center 3D Fitts' Law style task. Two of these interfaces (head orientation, EMG from muscles of the head and neck) could realistically be used by individuals with high tetraplegia, while the joystick was evaluated as a standard of high performance. Performance metrics were developed to assess the aspects of command source performance. Data were analyzed using a mixed model design ANOVA. Fixed effects were investigated between sources as well as for interactions between index of difficulty, command source, and the five performance measures used. A 5% threshold for statistical significance was used in the analysis. The performances of the three command interfaces were rather similar, though significant differences between command sources were observed. The apparent similarity is due in large part to the sequential command strategy (i.e., one dimension of movement at a time) typically adopted by the subjects. EMG-based commands were particularly pulsatile in nature. The use of sequential commands had a significant impact on each command source's performance for movements in two or three dimensions. While the sequential nature of the commands produced by the user did not fit with Fitts' Law, the other performance measures used were able to illustrate the properties of each command source. Though pulsatile, given the overall similarity between head orientation and the EMG interface, (which also could be readily included in a future implanted neuroprosthesis) the use of EMG as a command source for controlling an arm in 3D space is an attractive choice.

  12. From Antarctica to space: Use of telepresence and virtual reality in control of remote vehicles

    NASA Technical Reports Server (NTRS)

    Stoker, Carol; Hine, Butler P., III; Sims, Michael; Rasmussen, Daryl; Hontalas, Phil; Fong, Terrence W.; Steele, Jay; Barch, Don; Andersen, Dale; Miles, Eric

    1994-01-01

    In the Fall of 1993, NASA Ames deployed a modified Phantom S2 Remotely-Operated underwater Vehicle (ROV) into an ice-covered sea environment near McMurdo Science Station, Antarctica. This deployment was part of the antarctic Space Analog Program, a joint program between NASA and the National Science Foundation to demonstrate technologies relevant for space exploration in realistic field setting in the Antarctic. The goal of the mission was to operationally test the use of telepresence and virtual reality technology in the operator interface to a remote vehicle, while performing a benthic ecology study. The vehicle was operated both locally, from above a dive hole in the ice through which it was launched, and remotely over a satellite communications link from a control room at NASA's Ames Research Center. Local control of the vehicle was accomplished using the standard Phantom control box containing joysticks and switches, with the operator viewing stereo video camera images on a stereo display monitor. Remote control of the vehicle over the satellite link was accomplished using the Virtual Environment Vehicle Interface (VEVI) control software developed at NASA Ames. The remote operator interface included either a stereo display monitor similar to that used locally or a stereo head-mounted head-tracked display. The compressed video signal from the vehicle was transmitted to NASA Ames over a 768 Kbps satellite channel. Another channel was used to provide a bi-directional Internet link to the vehicle control computer through which the command and telemetry signals traveled, along with a bi-directional telephone service. In addition to the live stereo video from the satellite link, the operator could view a computer-generated graphic representation of the underwater terrain, modeled from the vehicle's sensors. The virtual environment contained an animate graphic model of the vehicle which reflected the state of the actual vehicle, along with ancillary information such as the vehicle track, science markers, and locations of video snapshots. The actual vehicle was driven either from within the virtual environment or through a telepresence interface. All vehicle functions could be controlled remotely over the satellite link.

  13. Implementation of a three degree of freedom, motor/brake hybrid force output device for virtual environment control tasks

    NASA Technical Reports Server (NTRS)

    Russo, Massimo; Tadros, Alfred; Flowers, Woodie; Zeltzer, David

    1991-01-01

    The advent of high resolution, physical model based computer graphics has left a gap in the design of input/output technology appropriate for interacting with such complex virtual world models. Since virtual worlds consist of physical models, it is appropriate to output the inherent force information necessary for the simulation to the user. The detailed design, construction, and control of a three degree freedom force output joystick will be presented. A novel kinematic design allows all three axes to be uncoupled, so that the system inertia matrix is diagonal. The two planar axes are actuated through an offset gimbal, and the third through a sleeved cable. To compensate for friction and inertia effects, this transmission is controlled by a force feedforward and a closed force feedback proportional loop. Workspace volume is a cone of 512 cubic inches, and the device bandwidth is maximized at 60 Hz for the two planar and 30 Hz for the third axis. Each axis is controlled by a motor/proportional magnetic particle brake combination fixed to the base. The innovative use of motors and brakes allows objects with high resistive torque requirements to be simulated without the stability and related safety issues involved with high torque, energy storing motors alone. Position, velocity, and applied endpoint force are sensed directly. Different control strategies are discussed and implemented, with an emphasis on how virtual environment force information, generated by the MIT Media Lab Computer Graphics and Animation Group BOLIO system, is transmitted to the device controller. The design constraints for a kinesthetic force feedback device can be summarized as: How can the symbiosis between the sense of presence in the virtual environment be maximized without compromising the interaction task under the constraints of the mechanical device limitations? Research in this field will yield insights to the optimal human sensory feedback mix for a wide spectrum of control and interaction problems. A flexible research tool that is designed as an easily reproducible product prototype has been constructed to explore the variety of possible force interaction.

  14. Interaction in planning movement direction for articulatory gestures and manual actions.

    PubMed

    Vainio, Lari; Tiainen, Mikko; Tiippana, Kaisa; Komeilipoor, Naeem; Vainio, Martti

    2015-10-01

    Some theories concerning speech mechanisms assume that overlapping representations are involved in programming certain articulatory gestures and hand actions. The present study investigated whether planning of movement direction for articulatory gestures and manual actions could interact. The participants were presented with written vowels (Experiment 1) or syllables (Experiment 2) that were associated with forward or backward movement of tongue (e.g., [i] vs. [ɑ] or [te] vs. [ke], respectively). They were required to pronounce the speech unit and simultaneously move the joystick forward or backward according to the color of the stimulus. Manual and vocal responses were performed relatively rapidly when the articulation and the hand action required movement into the same direction. The study suggests that planning horizontal tongue movements for articulation shares overlapping neural mechanisms with planning horizontal movement direction of hand actions.

  15. Remote control for motor vehicle

    NASA Technical Reports Server (NTRS)

    Johnson, Dale R. (Inventor); Ciciora, John A. (Inventor)

    1984-01-01

    A remote controller is disclosed for controlling the throttle, brake and steering mechanism of a conventional motor vehicle, with the remote controller being particularly advantageous for use by severely handicapped individuals. The controller includes a remote manipulator which controls a plurality of actuators through interfacing electronics. The remote manipulator is a two-axis joystick which controls a pair of linear actuators and a rotary actuator, with the actuators being powered by electric motors to effect throttle, brake and steering control of a motor vehicle adapted to include the controller. The controller enables the driver to control the adapted vehicle from anywhere in the vehicle with one hand with minimal control force and range of motion. In addition, even though a conventional vehicle is adapted for use with the remote controller, the vehicle may still be operated in the normal manner.

  16. Nintendo related injuries and other problems: review

    PubMed Central

    Heineman, Erik; Pierie, Jean-Pierre E N; ten Cate Hoedemaker, Henk O

    2014-01-01

    Objective To identify all reported cases of injury and other problems caused by using a Nintendo video gaming system. Design Review. Data sources and review methods Search of PubMed and Embase in June 2014 for reports on injuries and other problems caused by using a Nintendo gaming system. Results Most of the 38 articles identified were case reports or case series. Injuries and problems ranged from neurological and psychological to surgical. Traditional controllers with buttons were associated with tendinitis of the extensor of the thumb. The joystick on the Nintendo 64 controller was linked to palmar ulceration. The motion sensitive Wii remote was associated with musculoskeletal problems and various traumas. Conclusions Most problems are mild and prevalence is low. The described injuries were related to the way the games are controlled, which varies according to the video game console. PMID:25515525

  17. Comparison of manual steering and steering via joystick of a flexible rhino endoscope.

    PubMed

    Eckl, R; Gumprecht, J J; Strauss, G; Hofer, M; Dietz, A; Lueth, T C

    2010-01-01

    Flexible endoscopes are used in ENT surgery for examination tasks in cases wherever rigid endoscopes are unsuitable to reach certain positions in the nasal cavity. Until today they are steered by hand and no robotized system has been put into clinical practice. One qualification a robot manipulator system has to fulfill to be accepted is not to create new disadvantages compared to the conventional method in surgery. An important factor is the time needed to steer the new system compared to the time needed to steer the conventional system. In this article a robot manipulator system and an experiment are presented to compare the particular times test persons need to perform a certain task. This approach offers the possibility to benchmark the developed robot manipulator system and future systems for flexible rhino endoscopes.

  18. PyGaze: an open-source, cross-platform toolbox for minimal-effort programming of eyetracking experiments.

    PubMed

    Dalmaijer, Edwin S; Mathôt, Sebastiaan; Van der Stigchel, Stefan

    2014-12-01

    The PyGaze toolbox is an open-source software package for Python, a high-level programming language. It is designed for creating eyetracking experiments in Python syntax with the least possible effort, and it offers programming ease and script readability without constraining functionality and flexibility. PyGaze can be used for visual and auditory stimulus presentation; for response collection via keyboard, mouse, joystick, and other external hardware; and for the online detection of eye movements using a custom algorithm. A wide range of eyetrackers of different brands (EyeLink, SMI, and Tobii systems) are supported. The novelty of PyGaze lies in providing an easy-to-use layer on top of the many different software libraries that are required for implementing eyetracking experiments. Essentially, PyGaze is a software bridge for eyetracking research.

  19. Evaluating input device usability as a function of task difficulty in a tracking task.

    PubMed

    Rupp, Michael A; Oppold, Paul; McConnell, Daniel S

    2015-01-01

    Game controllers are emerging as a preferred choice for the manual control of unmanned vehicles, but an understanding of their usability characteristics has yet to emerge. We compared the usability of an Xbox 360 game controller in a dual task situation using MATB II to the traditional joystick and keyboard interface in two experiments. In the first experiment, performance with the game controller was associated with fewer tracking errors. In a second experiment, we trained users on the devices, and found that even after training the game controller was still associated with fewer tracking errors as well as higher usability and lower workload ratings. These results are consistent with the idea that game controllers are highly usable input devices and do not require high mental workload to operate, thus making them suitable for complex control tasks.

  20. The neural substrates of driving at a safe distance: a functional MRI study.

    PubMed

    Uchiyama, Yuji; Ebe, Kazutoshi; Kozato, Akio; Okada, Tomohisa; Sadato, Norihiro

    2003-12-11

    An important driving skill is the ability to maintain a safe distance from a preceding car. To determine the neural substrates of this skill we performed functional magnetic resonance imaging of simulated driving in 21 subjects. Subjects used a joystick to adjust their own driving speed in order to maintain a constant distance from a preceding car traveling at varying speeds. The task activated multiple brain regions. Activation of the cerebellum may reflect visual feedback during smooth tracking of the preceding car. Co-activation of the basal ganglia, thalamus and premotor cortex is related to movement selection. Activation of a premotor-parietal network is related to visuo-motor co-ordination. Task performance was negatively correlated with anterior cingulate activity, consistent with the role of this region in error detection and response selection.

  1. Combat PTSD and Implicit Behavioral Tendencies for Positive Affective Stimuli: A Brief Report

    PubMed Central

    Clausen, Ashley N.; Youngren, Westley; Sisante, Jason-Flor V.; Billinger, Sandra A.; Taylor, Charles; Aupperle, Robin L.

    2016-01-01

    Background: Prior cognitive research in posttraumatic stress disorder (PTSD) has focused on automatic responses to negative affective stimuli, including attentional facilitation or disengagement and avoidance action tendencies. More recent research suggests PTSD may also relate to differences in reward processing, which has lead to theories of PTSD relating to approach-avoidance imbalances. The current pilot study assessed how combat-PTSD symptoms relate to automatic behavioral tendencies to both positive and negative affective stimuli. Method: Twenty male combat veterans completed the approach-avoidance task (AAT), Clinician Administered PTSD Scale, Beck Depression Inventory-II, and State-Trait Anger Expression Inventory-II. During the AAT, subjects pulled (approach) or pushed (avoid) a joystick in response to neutral, happy, disgust, and angry faces based on border color. Bias scores were calculated for each emotion type (avoid-approach response latency differences). Main and interaction effects for psychological symptom severity and emotion type on bias score were assessed using linear mixed models. Results: There was a significant interaction between PTSD symptoms and emotion type, driven primarily by worse symptoms relating to a greater bias to avoid happy faces. Post hoc tests revealed that veterans with worse PTSD symptoms were slower to approach as well as quicker to avoid happy faces. Neither depressive nor anger symptoms related to avoid or approach tendencies of emotional stimuli. Conclusion: Posttraumatic stress disorder severity was associated with a bias for avoiding positive affective stimuli. These results provide further evidence that PTSD may relate to aberrant processing of positively valenced, or rewarding stimuli. Implicit responses to rewarding stimuli could be an important factor in PTSD pathology and treatment. Specifically, these findings have implications for recent endeavors in using computer-based interventions to influence automatic approach-avoidance tendencies. PMID:27252673

  2. The use of remote presence for health care delivery in a northern Inuit community: a feasibility study

    PubMed Central

    Mendez, Ivar; Jong, Michael; Keays-White, Debra; Turner, Gail

    2013-01-01

    Objective To evaluate the feasibility of remote presence for improving the health of residents in a remote northern Inuit community. Study design A pilot study assessed patient's, nurse's and physician's satisfaction with and the use of the remote presence technology aiding delivery of health care to a remote community. A preliminary cost analysis of this technology was also performed. Methods This study deployed a remote presence RP-7 robot to the isolated Inuit community of Nain, Newfoundland and Labrador for 15 months. The RP-7 is wirelessly controlled by a laptop computer equipped with audiovisual capability and a joystick to maneuver the robot in real time to aid in the assessing and care of patients from a distant location. Qualitative data on physician's, patient's, caregiver's and staff's satisfaction were collected as well as information on its use and characteristics and the number of air transports required to the referral center and associated costs. Results A total of 252 remote presence sessions occurred during the study period, with 89% of the sessions involving direct patient assessment or monitoring. Air transport was required in only 40% of the cases that would have been otherwise transported normally. Patients and their caregivers, nurses and physicians all expressed a high level of satisfaction with the remote presence technology and deemed it beneficial for improved patient care, workloads and job satisfaction. Conclusions These results show the feasibility of deploying a remote presence robot in a distant northern community and a high degree of satisfaction with the technology. Remote presence in the Canadian North has potential for delivering a cost-effective health care solution to underserviced communities reducing the need for the transport of patients and caregivers to distant referral centers. PMID:23984292

  3. The use of remote presence for health care delivery in a northern Inuit community: a feasibility study.

    PubMed

    Mendez, Ivar; Jong, Michael; Keays-White, Debra; Turner, Gail

    2013-01-01

    To evaluate the feasibility of remote presence for improving the health of residents in a remote northern Inuit community. A pilot study assessed patient's, nurse's and physician's satisfaction with and the use of the remote presence technology aiding delivery of health care to a remote community. A preliminary cost analysis of this technology was also performed. This study deployed a remote presence RP-7 robot to the isolated Inuit community of Nain, Newfoundland and Labrador for 15 months. The RP-7 is wirelessly controlled by a laptop computer equipped with audiovisual capability and a joystick to maneuver the robot in real time to aid in the assessing and care of patients from a distant location. Qualitative data on physician's, patient's, caregiver's and staff's satisfaction were collected as well as information on its use and characteristics and the number of air transports required to the referral center and associated costs. A total of 252 remote presence sessions occurred during the study period, with 89% of the sessions involving direct patient assessment or monitoring. Air transport was required in only 40% of the cases that would have been otherwise transported normally. Patients and their caregivers, nurses and physicians all expressed a high level of satisfaction with the remote presence technology and deemed it beneficial for improved patient care, workloads and job satisfaction. These results show the feasibility of deploying a remote presence robot in a distant northern community and a high degree of satisfaction with the technology. Remote presence in the Canadian North has potential for delivering a cost-effective health care solution to underserviced communities reducing the need for the transport of patients and caregivers to distant referral centers.

  4. The Language Research Center's Computerized Test System for environmental enrichment and psychological assessment

    NASA Technical Reports Server (NTRS)

    Washburn, D. A.; Rumbaugh, D. M.; Richardson, W. K.

    1992-01-01

    In the spring of 1987, we undertook to provide environmental enrichment to nonhuman primate subjects in ways that would complement and even contribute to the bio-behaviorial science that justified the monkeys' captivity. Of course, the psychological well-being of captive primates--and indeed all research species-- has been an area of intense research activity since the 1985 amendment of the Animal Welfare Act. This mandate for researchers to ensure the psychological, as well as physical, fitness of experimental animals catalyzed the humane and scientific interests of the research community. The contemporary literature is replete with proposed means both of assaying and of providing enrichment and well-being. Notwithstanding, consensus on either assessment or intervention has yet to be reached. The paradigm we employed was modelled after successful efforts with chimpanzees. An automated test system was constructed in which subjects responded to computer tasks by manipulating a joystick. The tasks, interactive game-like versions of many of the classic testing paradigms of cognitive and comparative psychology, permitted the controlled presentation of stimuli and demands without the required presence of a human experimenter. Despite significant barriers to the success, rhesus monkeys (Macaca mulatta) and a variety of other primate species (including, of course, humans) have mastered the skills necessary for testing in this paradigm. Previous experiments have illustrated the utility of the test system for addressing questions of learning, memory, attention, perception, and motivation. Additional data have been reported to support the contention that the Language Research Center's Computerized Test System (LRC-CTS) serves its other raison d'etre--providing environmental enrichment and assessing psychological well-being. This paper is designed to augment previous descriptions of the technology and the paradigm for scientists and caretakers interested in environmental enrichment and performance assessment with primates.

  5. Device- and system-independent personal touchless user interface for operating rooms : One personal UI to control all displays in an operating room.

    PubMed

    Ma, Meng; Fallavollita, Pascal; Habert, Séverine; Weidert, Simon; Navab, Nassir

    2016-06-01

    In the modern day operating room, the surgeon performs surgeries with the support of different medical systems that showcase patient information, physiological data, and medical images. It is generally accepted that numerous interactions must be performed by the surgical team to control the corresponding medical system to retrieve the desired information. Joysticks and physical keys are still present in the operating room due to the disadvantages of mouses, and surgeons often communicate instructions to the surgical team when requiring information from a specific medical system. In this paper, a novel user interface is developed that allows the surgeon to personally perform touchless interaction with the various medical systems, switch effortlessly among them, all of this without modifying the systems' software and hardware. To achieve this, a wearable RGB-D sensor is mounted on the surgeon's head for inside-out tracking of his/her finger with any of the medical systems' displays. Android devices with a special application are connected to the computers on which the medical systems are running, simulating a normal USB mouse and keyboard. When the surgeon performs interaction using pointing gestures, the desired cursor position in the targeted medical system display, and gestures, are transformed into general events and then sent to the corresponding Android device. Finally, the application running on the Android devices generates the corresponding mouse or keyboard events according to the targeted medical system. To simulate an operating room setting, our unique user interface was tested by seven medical participants who performed several interactions with the visualization of CT, MRI, and fluoroscopy images at varying distances from them. Results from the system usability scale and NASA-TLX workload index indicated a strong acceptance of our proposed user interface.

  6. Neo-angiogenesis metabolic biomarker of tumor-genesis tracking by infrared joystick contact imaging in personalized homecare system

    NASA Astrophysics Data System (ADS)

    Szu, Harold; Hoekstra, Philip; Landa, Joseph; Vydelingum, Nadarajen A.

    2014-05-01

    We describe an affordable, harmless, and administrative (AHA) metabolic biomarker (MBM) for homecare cancer screening. It may save hundreds of thousands of women's and thousands of men's lives every year from breast cancer and melanoma. The goal is to increase the specificity of infrared (IR) imagery to reduce the false alarm rate (FAR). The patient's hands are immersed in icy cold water, about 11oC, for 30 seconds. We then compare two IR images, taken before and after the cold stimulus, and the difference reveals an enhanced signal and noise ratio (SNR) at tumorigenesis sites since the contraction of capillaries under cold challenge is natural to healthy capillaries, except those newly built capillaries during angiogenesis (Folkman, Nature 1995). Concomitant with the genome and the phenome (molecular signaling by phosphor-mediate protein causing inflammation by platelet activating factor (PAF) that transform cells from benign to malignant is the amplification of nitric oxide (NO) syntheses, a short-lived reactive oxygen species (ROS) that dilates regional blood vessels; superseding normal autonomic nervous system regulation. A rapidly growing tumor site might implicate accumulation of ROS, for which NO can rapidly stretch the capillary bed system usually having thinning muscular lining known as Neo-Angiogenesis (NA) that could behave like Leaky In-situ Faucet Effect (LIFE) in response to cold challenge. To emphasize the state of art knowledge of NA, we mentioned in passing the first generation of an anticapillary growth drug, Avastin by Genetech; it is an antibody protein that is injected for metastasis, while the second generation drug; Sorafenib by Bayers (2001) and Sutent by Pfizer (2000) both target molecular signaling loci to block receptor associated tyrosine kinase induced protein phosphorylation in order to reverse the angiogenesis. Differentiating benign from malignant in a straightforward manner is required to achieve the wellness protocol, yet would become prohibitively expensive and impossible to follow through. For example, given the probability of detection (PD) about 0.1% over unspecified number of years (e.g. menopause years for breast cancer), one might need hundred thousand volunteers. We suggested a Time Reversal Invariant Paradigm (TRIP) (a private communication with Vatican) for gathering equivalent cancer symptom imagery from recovery histories of dozens of patients. We further mixed it with few % of recovered/non-sick cases for negative controls. Creating Virtual images and running videos of these, frame by frame, in two directions (forward and backward in time) resulted in identical Receiver Operation Characteristics (ROC) for both the computer Aided Target Recognition (AiTR) algorithm and the human radiological experts; namely PD versus FAR within the standard deviation; even though the physiology could be entirely different. Such a TRIP would be true taken by any memory-less instantaneous imagery devices (IR, ultrasound, X-rays, MRI excluding magnetic hysteresis memory). In summary, such an affordable, harmless, and administrative, neo-angiogenesis metabolic biomarker can help monitor the transitioning from benign to malignant states of high-risk home alone seniors and also monitor the progress of home alone seniors treatment at home. Therefore, Smartphone equipped with a day camera having IR spectral filtering for a contact self imaging called joystick, when augmented with AHA NA MBM, may be suited for HAS homecare.

  7. An advanced programmable/reconfigurable color graphics display system for crew station technology research

    NASA Technical Reports Server (NTRS)

    Montoya, R. J.; England, J. N.; Hatfield, J. J.; Rajala, S. A.

    1981-01-01

    The hardware configuration, software organization, and applications software for the NASA IKONAS color graphics display system are described. The systems were created at the Langley Research Center Display Device Laboratory to develop, evaluate, and demonstrate advanced generic concepts, technology, and systems integration techniques for electronic crew station systems of future civil aircraft. A minicomputer with 64K core memory acts as a host for a raster scan graphics display generator. The architectures of the hardware system and the graphics display system are provided. The applications software features a FORTRAN-based model of an aircraft, a display system, and the utility program for real-time communications. The model accepts inputs from a two-dimensional joystick and outputs a set of aircraft states. Ongoing and planned work for image segmentation/generation, specialized graphics procedures, and higher level language user interface are discussed.

  8. X-33 Flight Visualization

    NASA Technical Reports Server (NTRS)

    Laue, Jay H.

    1998-01-01

    The X-33 flight visualization effort has resulted in the integration of high-resolution terrain data with vehicle position and attitude data for planned flights of the X-33 vehicle from its launch site at Edwards AFB, California, to landings at Michael Army Air Field, Utah, and Maelstrom AFB, Montana. Video and Web Site representations of these flight visualizations were produced. In addition, a totally new module was developed to control viewpoints in real-time using a joystick input. Efforts have been initiated, and are presently being continued, for real-time flight coverage visualizations using the data streams from the X-33 vehicle flights. The flight visualizations that have resulted thus far give convincing support to the expectation that the flights of the X-33 will be exciting and significant space flight milestones... flights of this nation's one-half scale predecessor to its first single-stage-to-orbit, fully-reusable launch vehicle system.

  9. Intolerance for approach of ambiguity in social anxiety disorder.

    PubMed

    Kuckertz, Jennie M; Strege, Marlene V; Amir, Nader

    2017-06-01

    Previous research has utilised the approach-avoidance task (AAT) to measure approach and avoidance action tendencies in socially anxious individuals. "Neutral" social stimuli may be perceived as ambiguous and hence threatening to socially anxious individuals, however it is unclear whether this results in difficulty approaching ambiguous ("neutral") versus unambiguous threat (e.g. disgust) faces (i.e. intolerance of ambiguity). Thirty participants with social anxiety disorder (SADs) and 29 non-anxious controls completed an implicit AAT in which they were instructed to approach or avoid neutral and disgust faces (i.e. pull or push a joystick) based on colour of the picture border. Results indicated that SADs demonstrated greater difficulty approaching neutral relative to disgust faces. Moreover, intolerance for approach of ambiguity predicted social anxiety severity while controlling for the effects of trait anxiety and depression. Our results provide further support for the role of intolerance of ambiguity in SAD.

  10. Alternative input medium development for wheelchair user with severe spinal cord injury

    NASA Astrophysics Data System (ADS)

    Ihsan, Izzat Aqmar; Tomari, Razali; Zakaria, Wan Nurshazwani Wan; Othman, Nurmiza

    2017-09-01

    Quadriplegia or tetraplegia patients have restricted four limbs as well as torso movement caused by severe spinal cord injury. Undoubtedly, these patients face difficulties when operating their powered electric wheelchair since they are unable to control the wheelchair by means of a standard joystick. Due to total loss of both sensory and motor function of the four limbs and torso, an alternative input medium for the wheelchair will be developed to assist the user in operating the wheelchair. In this framework, the direction of the wheelchair movement is determined by the user's conscious intent through a brain control interface (BCI) based on Electroencephalogram (EEG) signal. A laser range finder (LFR) is used to perceive environment information for determining a safety distance of the wheelchair's surrounding. Local path planning algorithm will be developed to provide navigation planner along with user's input to prevent collision during control operation.

  11. Robot Teleoperation and Perception Assistance with a Virtual Holographic Display

    NASA Technical Reports Server (NTRS)

    Goddard, Charles O.

    2012-01-01

    Teleoperation of robots in space from Earth has historically been dfficult. Speed of light delays make direct joystick-type control infeasible, so it is desirable to command a robot in a very high-level fashion. However, in order to provide such an interface, knowledge of what objects are in the robot's environment and how they can be interacted with is required. In addition, many tasks that would be desirable to perform are highly spatial, requiring some form of six degree of freedom input. These two issues can be combined, allowing the user to assist the robot's perception by identifying the locations of objects in the scene. The zSpace system, a virtual holographic environment, provides a virtual three-dimensional space superimposed over real space and a stylus tracking position and rotation inside of it. Using this system, a possible interface for this sort of robot control is proposed.

  12. Transfer of learning in choice reactions: The roles of stimulus type, response mode, and set-level compatibility.

    PubMed

    Yamaguchi, Motonori; Chen, Jing; Proctor, Robert W

    2015-08-01

    The Simon effect refers to the advantage of responding to spatially compatible stimuli. This effect can be eliminated or even reversed to favor spatially incompatible stimuli after participants practice a choice-reaction task with spatially incompatible mappings (e.g., pressing left and right keys to stimuli on the right and left, respectively). This transfer of incompatible spatial associations has been observed under conditions in which responses were made manually (e.g., keypresses, moving a joystick). The present study used vocal responses to reveal the primary determinants of the transfer effect, dissociating the influences of stimulus type, response mode, and their interaction (set-level compatibility). The results suggest that contextual match between the practice and transfer tasks with respect to stimulus type and response mode determined transfer of incompatible associations to the Simon task, and stimulus type determined the efficiency of acquiring new associations. However, there was little evidence that set-level compatibility plays any major role in either acquisition or transfer of spatial associations.

  13. Retraining automatic action tendencies changes alcoholic patients' approach bias for alcohol and improves treatment outcome.

    PubMed

    Wiers, Reinout W; Eberl, Carolin; Rinck, Mike; Becker, Eni S; Lindenmeyer, Johannes

    2011-04-01

    This study tested the effects of a new cognitive-bias modification (CBM) intervention that targeted an approach bias for alcohol in 214 alcoholic inpatients. Patients were assigned to one of two experimental conditions, in which they were explicitly or implicitly trained to make avoidance movements (pushing a joystick) in response to alcohol pictures, or to one of two control conditions, in which they received no training or sham training. Four brief sessions of experimental CBM preceded regular inpatient treatment. In the experimental conditions only, patients' approach bias changed into an avoidance bias for alcohol. This effect generalized to untrained pictures in the task used in the CBM and to an Implicit Association Test, in which alcohol and soft-drink words were categorized with approach and avoidance words. Patients in the experimental conditions showed better treatment outcomes a year later. These findings indicate that a short intervention can change alcoholics' automatic approach bias for alcohol and may improve treatment outcome.

  14. Investigation of automatic avoidance in displaced individuals with chronic Posttraumatic Stress Disorder (PTSD).

    PubMed

    Wittekind, Charlotte E; Behmer, Friederike; Muhtz, Christoph; Fritzsche, Anja; Moritz, Steffen; Jelinek, Lena

    2015-08-30

    Avoidance of trauma-related stimuli is a key feature of Posttraumatic Stress Disorder (PTSD). However, avoidance has almost exclusively been investigated with explicit measures targeting more strategic aspects of behavior. The aim of the present study was to examine automatic avoidance in older individuals displaced as children at the end of World War II with (n=22) and without PTSD (n=26) and in non-traumatized control participants (n=23) with an Approach-Avoidance Task (AAT). Participants were instructed to respond to the color (gray, brown) of trauma-related, neutral, and control pictures by pushing or pulling a joystick. Groups did not differ significantly as to their behavioral tendencies towards trauma-related pictures. Thus, there was no evidence for automatic avoidance in individuals with PTSD. However, high vigilance was associated with stronger implicit avoidance towards trauma-related pictures in the PTSD group. Several explanations for the non-significant results as well as implications and limitations of the present findings are discussed. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  15. Direct interaction with an assistive robot for individuals with chronic stroke.

    PubMed

    Kmetz, Brandon; Markham, Heather; Brewer, Bambi R

    2011-01-01

    Many robotic systems have been developed to provide assistance to individuals with disabilities. Most of these systems require the individual to interact with the robot via a joystick or keypad, though some utilize techniques such as speech recognition or selection of objects with a laser pointer. In this paper, we describe a prototype system using a novel method of interaction with an assistive robot. A touch-sensitive skin enables the user to directly guide a robotic arm to a desired position. When the skin is released, the robot remains fixed in position. The target population for this system is individuals with hemiparesis due to chronic stroke. The system can be used as a substitute for the paretic arm and hand in bimanual tasks such as holding a jar while removing the lid. This paper describes the hardware and software of the prototype system, which includes a robotic arm, the touch-sensitive skin, a hook-style prehensor, and weight compensation and speech recognition software.

  16. Acute effects of intoxication and arousal on approach / avoidance biases toward sexual risk stimuli in heterosexual men

    PubMed Central

    Simons, Jeffrey S.; Maisto, Stephen A.; Wray, Tyler B.; Emery, Noah N.

    2015-01-01

    This study tested the effects of alcohol intoxication and physiological arousal on cognitive biases toward erotic stimuli and condoms. Ninety-seven heterosexual men were randomized to 1 of 6 independent conditions in a 2 (high arousal or control) × 3 (alcohol target BAC = 0.08), placebo, or juice control) design and then completed a variant of the Approach Avoidance Task (AAT). The AAT assessed reaction times toward approaching and avoiding erotic stimuli and condoms with a joystick. Consistent with hypotheses, the alcohol condition exhibited an approach bias toward erotic stimuli, whereas the control and placebo groups exhibited an approach bias toward condom stimuli. Similarly, the participants in the high arousal condition exhibited an approach bias toward erotic stimuli and the low arousal control condition exhibited an approach bias toward condoms. The results suggest that acute changes in intoxication and physiological arousal independently foster biased responding towards sexual stimuli and these biases are associated with sexual risk intentions. PMID:25808719

  17. Task relevance predicts gaze in videos of real moving scenes.

    PubMed

    Howard, Christina J; Gilchrist, Iain D; Troscianko, Tom; Behera, Ardhendu; Hogg, David C

    2011-09-01

    Low-level stimulus salience and task relevance together determine the human fixation priority assigned to scene locations (Fecteau and Munoz in Trends Cogn Sci 10(8):382-390, 2006). However, surprisingly little is known about the contribution of task relevance to eye movements during real-world visual search where stimuli are in constant motion and where the 'target' for the visual search is abstract and semantic in nature. Here, we investigate this issue when participants continuously search an array of four closed-circuit television (CCTV) screens for suspicious events. We recorded eye movements whilst participants watched real CCTV footage and moved a joystick to continuously indicate perceived suspiciousness. We find that when multiple areas of a display compete for attention, gaze is allocated according to relative levels of reported suspiciousness. Furthermore, this measure of task relevance accounted for twice the amount of variance in gaze likelihood as the amount of low-level visual changes over time in the video stimuli.

  18. Evaluation of the cognitive effects of travel technique in complex real and virtual environments.

    PubMed

    Suma, Evan A; Finkelstein, Samantha L; Reid, Myra; V Babu, Sabarish; Ulinski, Amy C; Hodges, Larry F

    2010-01-01

    We report a series of experiments conducted to investigate the effects of travel technique on information gathering and cognition in complex virtual environments. In the first experiment, participants completed a non-branching multilevel 3D maze at their own pace using either real walking or one of two virtual travel techniques. In the second experiment, we constructed a real-world maze with branching pathways and modeled an identical virtual environment. Participants explored either the real or virtual maze for a predetermined amount of time using real walking or a virtual travel technique. Our results across experiments suggest that for complex environments requiring a large number of turns, virtual travel is an acceptable substitute for real walking if the goal of the application involves learning or reasoning based on information presented in the virtual world. However, for applications that require fast, efficient navigation or travel that closely resembles real-world behavior, real walking has advantages over common joystick-based virtual travel techniques.

  19. Emotional expressions in voice and music: same code, same effect?

    PubMed

    Escoffier, Nicolas; Zhong, Jidan; Schirmer, Annett; Qiu, Anqi

    2013-08-01

    Scholars have documented similarities in the way voice and music convey emotions. By using functional magnetic resonance imaging (fMRI) we explored whether these similarities imply overlapping processing substrates. We asked participants to trace changes in either the emotion or pitch of vocalizations and music using a joystick. Compared to music, vocalizations more strongly activated superior and middle temporal cortex, cuneus, and precuneus. However, despite these differences, overlapping rather than differing regions emerged when comparing emotion with pitch tracing for music and vocalizations, respectively. Relative to pitch tracing, emotion tracing activated medial superior frontal and anterior cingulate cortex regardless of stimulus type. Additionally, we observed emotion specific effects in primary and secondary auditory cortex as well as in medial frontal cortex that were comparable for voice and music. Together these results indicate that similar mechanisms support emotional inferences from vocalizations and music and that these mechanisms tap on a general system involved in social cognition. Copyright © 2011 Wiley Periodicals, Inc.

  20. Experimental setup for evaluating an adaptive user interface for teleoperation control

    NASA Astrophysics Data System (ADS)

    Wijayasinghe, Indika B.; Peetha, Srikanth; Abubakar, Shamsudeen; Saadatzi, Mohammad Nasser; Cremer, Sven; Popa, Dan O.

    2017-05-01

    A vital part of human interactions with a machine is the control interface, which single-handedly could define the user satisfaction and the efficiency of performing a task. This paper elaborates the implementation of an experimental setup to study an adaptive algorithm that can help the user better tele-operate the robot. The formulation of the adaptive interface and associate learning algorithms are general enough to apply when the mapping between the user controls and the robot actuators is complex and/or ambiguous. The method uses a genetic algorithm to find the optimal parameters that produce the input-output mapping for teleoperation control. In this paper, we describe the experimental setup and associated results that was used to validate the adaptive interface to a differential drive robot from two different input devices; a joystick, and a Myo gesture control armband. Results show that after the learning phase, the interface converges to an intuitive mapping that can help even inexperienced users drive the system to a goal location.

  1. The impact of facial emotional expressions on behavioral tendencies in females and males

    PubMed Central

    Seidel, Eva-Maria; Habel, Ute; Kirschner, Michaela; Gur, Ruben C.; Derntl, Birgit

    2010-01-01

    Emotional faces communicate both the emotional state and behavioral intentions of an individual. They also activate behavioral tendencies in the perceiver, namely approach or avoidance. Here, we compared more automatic motor to more conscious rating responses to happy, sad, angry and disgusted faces in a healthy student sample. Happiness was associated with approach and anger with avoidance. However, behavioral tendencies in response to sadness and disgust were more complex. Sadness produced automatic approach but conscious withdrawal, probably influenced by interpersonal relations or personality. Disgust elicited withdrawal in the rating task whereas no significant tendency emerged in the joystick task, probably driven by expression style. Based on our results it is highly relevant to further explore actual reactions to emotional expressions and to differentiate between automatic and controlled processes since emotional faces are used in various kinds of studies. Moreover, our results highlight the importance of gender of poser effects when applying emotional expressions as stimuli. PMID:20364933

  2. Finite State Machine with Adaptive Electromyogram (EMG) Feature Extraction to Drive Meal Assistance Robot

    NASA Astrophysics Data System (ADS)

    Zhang, Xiu; Wang, Xingyu; Wang, Bei; Sugi, Takenao; Nakamura, Masatoshi

    Surface electromyogram (EMG) from elbow, wrist and hand has been widely used as an input of multifunction prostheses for many years. However, for patients with high-level limb deficiencies, muscle activities in upper-limbs are not strong enough to be used as control signals. In this paper, EMG from lower-limbs is acquired and applied to drive a meal assistance robot. An onset detection method with adaptive threshold based on EMG power is proposed to recognize different muscle contractions. Predefined control commands are output by finite state machine (FSM), and applied to operate the robot. The performance of EMG control is compared with joystick control by both objective and subjective indices. The results show that FSM provides the user with an easy-performing control strategy, which successfully operates robots with complicated control commands by limited muscle motions. The high accuracy and comfortableness of the EMG-control meal assistance robot make it feasible for users with upper limbs motor disabilities.

  3. Binocular Perception of 2D Lateral Motion and Guidance of Coordinated Motor Behavior.

    PubMed

    Fath, Aaron J; Snapp-Childs, Winona; Kountouriotis, Georgios K; Bingham, Geoffrey P

    2016-04-01

    Zannoli, Cass, Alais, and Mamassian (2012) found greater audiovisual lag between a tone and disparity-defined stimuli moving laterally (90-170 ms) than for disparity-defined stimuli moving in depth or luminance-defined stimuli moving laterally or in depth (50-60 ms). We tested if this increased lag presents an impediment to visually guided coordination with laterally moving objects. Participants used a joystick to move a virtual object in several constant relative phases with a laterally oscillating stimulus. Both the participant-controlled object and the target object were presented using a disparity-defined display that yielded information through changes in disparity over time (CDOT) or using a luminance-defined display that additionally provided information through monocular motion and interocular velocity differences (IOVD). Performance was comparable for both disparity-defined and luminance-defined displays in all relative phases. This suggests that, despite lag, perception of lateral motion through CDOT is generally sufficient to guide coordinated motor behavior.

  4. Innovative Power Wheelchair Control Interface: A Proof-of-Concept Study

    PubMed Central

    Romero, Sergio; Prather, Emily; Ramroop, Marisa; Slaibe, Emmy; Christensen, Matthew

    2016-01-01

    Some people without independent mobility are candidates for powered mobility but are unable to use a traditional power wheelchair joystick. This proof-of-concept study tested and further developed an innovative method of driving power wheelchairs for people whose impairments prevent them from operating commercial wheelchair controls. Our concept, Self-referenced Personal Orthotic Omni-purpose Control Interface (SPOOCI), is distinguished by referencing the control sensor not to the wheelchair frame but instead to the adjacent proximal lower-extremity segment via a custom-formed orthosis. Using a descriptive case-series design, we compared the pre–post functional power wheelchair driving skill data of 4 participants, measured by the Power Mobility Program, using descriptive analyses. The intervention consisted of standard-care power wheelchair training during 12 outpatient occupational or physical therapy sessions. All 4 participants who completed the 12-wk intervention improved their functional power wheelchair driving skills using SPOOCI, but only 3 were deemed safe to continue with power wheelchair driving. PMID:26943118

  5. A biotic video game smart phone kit for formal and informal biophysics education

    NASA Astrophysics Data System (ADS)

    Kim, Honesty; Lee, Seung Ah; Riedel-Kruse, Ingmar

    2015-03-01

    Novel ways for formal and informal biophysics education are important. We present a low-cost biotic game design kit that incorporates microbial organisms into an interactive gaming experience: A 3D-printable microscope containing four LEDs controlled by a joystick enable human players to provide directional light stimuli to the motile single-celled organism Euglena gracilis. These cellular behaviors are displayed on the integrated smart phone. Real time cell-tracking couples these cells into interactive biotic video game play, i.e., the human player steers Euglena to play soccer with virtual balls and goals. The player's learning curve in mastering this fun game is intrinsically coupled to develop a deeper knowledge about Euglena's cell morphology and the biophysics of its phototactic behavior. This kit is dual educational - via construction and via play - and it provides an engaging theme for a formal biophysics devices class as well as to be presented in informal outreach activities; its low cost and open soft- and hardware should enable wide adoption.

  6. Collocation and Pattern Recognition Effects on System Failure Remediation

    NASA Technical Reports Server (NTRS)

    Trujillo, Anna C.; Press, Hayes N.

    2007-01-01

    Previous research found that operators prefer to have status, alerts, and controls located on the same screen. Unfortunately, that research was done with displays that were not designed specifically for collocation. In this experiment, twelve subjects evaluated two displays specifically designed for collocating system information against a baseline that consisted of dial status displays, a separate alert area, and a controls panel. These displays differed in the amount of collocation, pattern matching, and parameter movement compared to display size. During the data runs, subjects kept a randomly moving target centered on a display using a left-handed joystick and they scanned system displays to find a problem in order to correct it using the provided checklist. Results indicate that large parameter movement aided detection and then pattern recognition is needed for diagnosis but the collocated displays centralized all the information subjects needed, which reduced workload. Therefore, the collocated display with large parameter movement may be an acceptable display after familiarization because of the possible pattern recognition developed with training and its use.

  7. Remote presence proctoring by using a wireless remote-control videoconferencing system.

    PubMed

    Smith, C Daniel; Skandalakis, John E

    2005-06-01

    Remote presence in an operating room to allow an experienced surgeon to proctor a surgeon has been promised through robotics and telesurgery solutions. Although several such systems have been developed and commercialized, little progress has been made using telesurgery for anything more than live demonstrations of surgery. This pilot project explored the use of a new videoconferencing capability to determine if it offers advantages over existing systems. The video conferencing system used is a PC-based system with a flat screen monitor and an attached camera that is then mounted on a remotely controlled platform. This device is controlled from a remotely placed PC-based videoconferencing system computer outfitted with a joystick. Using the public Internet and a wireless router at the client site, a surgeon at the control station can manipulate the videoconferencing system. Controls include navigating the unit around the room and moving the flat screen/camera portion like a head looking up/down and right/left. This system (InTouch Medical, Santa Barbara, CA) was used to proctor medical students during an anatomy class cadaver dissection. The ability of the remote surgeon to effectively monitor the students' dissections and direct their activities was assessed subjectively by students and surgeon. This device was very effective at providing a controllable and interactive presence in the anatomy lab. Students felt they were interacting with a person rather than a video screen and quickly forgot that the surgeon was not in the room. The ability to move the device within the environment rather than just observe the environment from multiple fixed camera angles gave the surgeon a similar feel of true presence. A remote-controlled videoconferencing system provides a more real experience for both student and proctor. Future development of such a device could greatly facilitate progress in implementation of remote presence proctoring.

  8. The 50s cliff: a decline in perceptuo-motor learning, not a deficit in visual motion perception.

    PubMed

    Ren, Jie; Huang, Shaochen; Zhang, Jiancheng; Zhu, Qin; Wilson, Andrew D; Snapp-Childs, Winona; Bingham, Geoffrey P

    2015-01-01

    Previously, we measured perceptuo-motor learning rates across the lifespan and found a sudden drop in learning rates between ages 50 and 60, called the "50s cliff." The task was a unimanual visual rhythmic coordination task in which participants used a joystick to oscillate one dot in a display in coordination with another dot oscillated by a computer. Participants learned to produce a coordination with a 90° relative phase relation between the dots. Learning rates for participants over 60 were half those of younger participants. Given existing evidence for visual motion perception deficits in people over 60 and the role of visual motion perception in the coordination task, it remained unclear whether the 50s cliff reflected onset of this deficit or a genuine decline in perceptuo-motor learning. The current work addressed this question. Two groups of 12 participants in each of four age ranges (20s, 50s, 60s, 70s) learned to perform a bimanual coordination of 90° relative phase. One group trained with only haptic information and the other group with both haptic and visual information about relative phase. Both groups were tested in both information conditions at baseline and post-test. If the 50s cliff was caused by an age dependent deficit in visual motion perception, then older participants in the visual group should have exhibited less learning than those in the haptic group, which should not exhibit the 50s cliff, and older participants in both groups should have performed less well when tested with visual information. Neither of these expectations was confirmed by the results, so we concluded that the 50s cliff reflects a genuine decline in perceptuo-motor learning with aging, not the onset of a deficit in visual motion perception.

  9. Translational Vestibulo-Ocular Reflex and Motion Perception During Interaural Linear Acceleration: Comparison of Different Motion Paradigms

    NASA Technical Reports Server (NTRS)

    Beaton, K. H.; Holly, J. E.; Clement, G. R.; Wood, S. J.

    2011-01-01

    The neural mechanisms to resolve ambiguous tilt-translation motion have been hypothesized to be different for motion perception and eye movements. Previous studies have demonstrated differences in ocular and perceptual responses using a variety of motion paradigms, including Off-Vertical Axis Rotation (OVAR), Variable Radius Centrifugation (VRC), translation along a linear track, and tilt about an Earth-horizontal axis. While the linear acceleration across these motion paradigms is presumably equivalent, there are important differences in semicircular canal cues. The purpose of this study was to compare translation motion perception and horizontal slow phase velocity to quantify consistencies, or lack thereof, across four different motion paradigms. Twelve healthy subjects were exposed to sinusoidal interaural linear acceleration between 0.01 and 0.6 Hz at 1.7 m/s/s (equivalent to 10 tilt) using OVAR, VRC, roll tilt, and lateral translation. During each trial, subjects verbally reported the amount of perceived peak-to-peak lateral translation and indicated the direction of motion with a joystick. Binocular eye movements were recorded using video-oculography. In general, the gain of translation perception (ratio of reported linear displacement to equivalent linear stimulus displacement) increased with stimulus frequency, while the phase did not significantly vary. However, translation perception was more pronounced during both VRC and lateral translation involving actual translation, whereas perceptions were less consistent and more variable during OVAR and roll tilt which did not involve actual translation. For each motion paradigm, horizontal eye movements were negligible at low frequencies and showed phase lead relative to the linear stimulus. At higher frequencies, the gain of the eye movements increased and became more inphase with the acceleration stimulus. While these results are consistent with the hypothesis that the neural computational strategies for motion perception and eye movements differ, they also indicate that the specific motion platform employed can have a significant effect on both the amplitude and phase of each.

  10. Masked and unmasked error-related potentials during continuous control and feedback

    NASA Astrophysics Data System (ADS)

    Lopes Dias, Catarina; Sburlea, Andreea I.; Müller-Putz, Gernot R.

    2018-06-01

    The detection of error-related potentials (ErrPs) in tasks with discrete feedback is well established in the brain–computer interface (BCI) field. However, the decoding of ErrPs in tasks with continuous feedback is still in its early stages. Objective. We developed a task in which subjects have continuous control of a cursor’s position by means of a joystick. The cursor’s position was shown to the participants in two different modalities of continuous feedback: normal and jittered. The jittered feedback was created to mimic the instability that could exist if participants controlled the trajectory directly with brain signals. Approach. This paper studies the electroencephalographic (EEG)—measurable signatures caused by a loss of control over the cursor’s trajectory, causing a target miss. Main results. In both feedback modalities, time-locked potentials revealed the typical frontal-central components of error-related potentials. Errors occurring during the jittered feedback (masked errors) were delayed in comparison to errors occurring during normal feedback (unmasked errors). Masked errors displayed lower peak amplitudes than unmasked errors. Time-locked classification analysis allowed a good distinction between correct and error classes (average Cohen-, average TPR  =  81.8% and average TNR  =  96.4%). Time-locked classification analysis between masked error and unmasked error classes revealed results at chance level (average Cohen-, average TPR  =  60.9% and average TNR  =  58.3%). Afterwards, we performed asynchronous detection of ErrPs, combining both masked and unmasked trials. The asynchronous detection of ErrPs in a simulated online scenario resulted in an average TNR of 84.0% and in an average TPR of 64.9%. Significance. The time-locked classification results suggest that the masked and unmasked errors were indistinguishable in terms of classification. The asynchronous classification results suggest that the feedback modality did not hinder the asynchronous detection of ErrPs.

  11. Effect of Target Location on Dynamic Visual Acuity During Passive Horizontal Rotation

    NASA Technical Reports Server (NTRS)

    Appelbaum, Meghan; DeDios, Yiri; Kulecz, Walter; Peters, Brian; Wood, Scott

    2010-01-01

    The vestibulo-ocular reflex (VOR) generates eye rotation to compensate for potential retinal slip in the specific plane of head movement. Dynamic visual acuity (DVA) has been utilized as a functional measure of the VOR. The purpose of this study was to examine changes in accuracy and reaction time when performing a DVA task with targets offset from the plane of rotation, e.g. offset vertically during horizontal rotation. Visual acuity was measured in 12 healthy subjects as they moved a hand-held joystick to indicate the orientation of a computer-generated Landolt C "as quickly and accurately as possible." Acuity thresholds were established with optotypes presented centrally on a wall-mounted LCD screen at 1.3 m distance, first without motion (static condition) and then while oscillating at 0.8 Hz (DVA, peak velocity 60 deg/s). The effect of target location was then measured during horizontal rotation with the optotypes randomly presented in one of nine different locations on the screen (offset up to 10 deg). The optotype size (logMar 0, 0.2 or 0.4, corresponding to Snellen range 20/20 to 20/50) and presentation duration (150, 300 and 450 ms) were counter-balanced across five trials, each utilizing horizontal rotation at 0.8 Hz. Dynamic acuity was reduced relative to static acuity in 7 of 12 subjects by one step size. During the random target trials, both accuracy and reaction time improved proportional to optotype size. Accuracy and reaction time also improved between 150 ms and 300 ms presentation durations. The main finding was that both accuracy and reaction time varied as a function of target location, with greater performance decrements when acquiring vertical targets. We conclude that dynamic visual acuity varies with target location, with acuity optimized for targets in the plane of motion. Both reaction time and accuracy are functionally relevant DVA parameters of VOR function.

  12. [Visual–manual tracking after long spaceflight].

    PubMed

    2016-01-01

    This study presents the results of the pre- and postflight clinical and physiological examination (CPE) and scientific experiment “Sensory Adaptation-2” carried out in Yu.A. Gagarin Research & Test Cosmonaut Training Center. There were examined 14 Russian cosmonauts, crewmembers of long-term international spaceflights ISS-28/29 to ISS 36/37, who were in microgravity from 159 to 195 days. Age of the cosmonauts was 35–50 years. Studies were conducted twice before space flight (baseline), and on days R+1(2), R+4(5), and R+8(9) after landing. In the study of visual–manual tracking (VMT), eye movements were recorded by the electrooculography method (EOG), hand movements - by a joystick using biological visual feedback (on the screen represented the current angle/position of a joystick). Examinations were conducted using computerized stimulation programs, which were presented on the screen of the hardware-software complex "Sensomotor". Examinations of the VMT took place in the dialog mode and included the following sections: a) EOG-calibration; b) visual-manual tracking within ±10° on the screen with blank background (smooth linear and sinusoidal movement of a point target with a frequency of 0.16 Hz in the vertical and horizontal directions). There were evaluated time, amplitude, and velocity characteristics of visual and manual tracking (VT and MT), including the effectiveness (EC) and gain (GC) coefficients which were calculated respectively, as the ratio of amplitude and velocity of the visual stimulus (target). A study of the vestibular function (VF) was performed before and after space flight using videooculography. There were assessed static torsion otolith–cervical–ocular reflex, dynamic vestibular–cervical–ocular reactions, vestibular reactivity, spontaneous eye movements. Study of VF in the first postflight has shown a sharp decrease (up to its complete absence) of static vestibular excitability (otolith reflex) accompanied by the increased dynamic reactivity of the vestibular system. Study of VTM has shown a significant decrease of gain and effectiveness/amplitud of VT in the first days postflight, as well as correlation between the parameters of VF and MT, between the VF and VT, and no found correlation between parameters of VF and MT. It was found that the conditions of space flight (microgravity) have a greater impact on the accuracy of the VT than the accuracy of MT. Full return of characteristics of the VMT and VF to the baseline was observed on R+8(9) days after space flight.

  13. Determine Optimal Stimulus Amplitude for Using Vestibular Stochastic Stimulation to Improve Balance Function

    NASA Technical Reports Server (NTRS)

    Goel, R.; Kofman, I.; DeDios, Y. E.; Jeevarajan, J.; Stepanyan, V.; Nair, M.; Congdon, S.; Fregia, M.; Cohen, H.; Bloomberg, J.J.; hide

    2015-01-01

    Sensorimotor changes such as postural and gait instabilities can affect the functional performance of astronauts when they transition across different gravity environments. We are developing a method, based on stochastic resonance (SR), to enhance information transfer by applying non-zero levels of external noise on the vestibular system (vestibular stochastic resonance, VSR). Our previous work has shown the advantageous effects of VSR in a balance task of standing on an unstable surface [1]. This technique to improve detection of vestibular signals uses a stimulus delivery system that provides imperceptibly low levels of white noise-based binaural bipolar electrical stimulation of the vestibular system. The goal of this project is to determine optimal levels of stimulation for SR applications by using a defined vestibular threshold of motion detection. A series of experiments were carried out to determine a robust paradigm to identify a vestibular threshold that can then be used to recommend optimal stimulation levels for sensorimotor adaptability (SA) training applications customized to each crewmember. The amplitude of stimulation to be used in the VSR application has varied across studies in the literature such as 60% of nociceptive stimulus thresholds [2]. We compared subjects' perceptual threshold with that obtained from two measures of body sway. Each test session was 463s long and consisted of several 15s long sinusoidal stimuli, at different current amplitudes (0-2 mA), interspersed with 20-20.5s periods of no stimulation. Subjects sat on a chair with their eyes closed and had to report their perception of motion through a joystick. A force plate underneath the chair recorded medio-lateral shear forces and roll moments. Comparison of threshold of motion detection obtained from joystick data versus body sway suggests that perceptual thresholds were significantly lower. In the balance task, subjects stood on an unstable surface and had to maintain balance, and the stimulation was administered from 20-400% of subjects' vestibular threshold. Optimal stimulation amplitude was determined at which the balance performance was best compared to control (no stimulation). Preliminary results show that, in general, using stimulation amplitudes at 40-60% of perceptual motion threshold significantly improved the balance performance. We hypothesize that VSR stimulation will act synergistically with SA training to improve adaptability by increasing utilization of vestibular information and therefore will help us to optimize and personalize a SA countermeasure prescription. This combination may help to significantly reduce the number of days required to recover functional performance to preflight levels after long-duration spaceflight.

  14. A decade of telerobotics in rehabilitation: Demonstrated utility blocked by the high cost of manipulation and the complexity of the user interface

    NASA Technical Reports Server (NTRS)

    Leifer, Larry; Michalowski, Stefan; Vanderloos, Machiel

    1991-01-01

    The Stanford/VA Interactive Robotics Laboratory set out in 1978 to test the hypothesis that industrial robotics technology could be applied to serve the manipulation needs of severely impaired individuals. Five generations of hardware, three generations of system software, and over 125 experimental subjects later, we believe that genuine utility is achievable. The experience includes development of over 65 task applications using voiced command, joystick control, natural language command and 3D object designation technology. A brief foray into virtual environments, using flight simulator technology, was instructive. If reality and virtuality come for comparable prices, you cannot beat reality. A detailed review of assistive robot anatomy and the performance specifications needed to achieve cost/beneficial utility will be used to support discussion of the future of rehabilitation telerobotics. Poised on the threshold of commercial viability, but constrained by the high cost of technically adequate manipulators, this worthy application domain flounders temporarily. In the long run, it will be the user interface that governs utility.

  15. Rapid social perception is flexible: approach and avoidance motivational states shape P100 responses to other-race faces

    PubMed Central

    Cunningham, William A.; Van Bavel, Jay J.; Arbuckle, Nathan L.; Packer, Dominic J.; Waggoner, Ashley S.

    2012-01-01

    Research on person categorization suggests that people automatically and inflexibly categorize others according to group memberships, such as race. Consistent with this view, research using electroencephalography (EEG) has found that White participants tend to show an early difference in processing Black versus White faces. Yet, new research has shown that these ostensibly automatic biases may not be as inevitable as once thought and that motivational influences may be able to eliminate these biases. It is unclear, however, whether motivational influences shape the initial biases or whether these biases can only be modulated by later, controlled processes. Using EEG to examine the time course of biased processing, we manipulated approach and avoidance motivational states by having participants pull or push a joystick, respectively, while viewing White or Black faces. Consistent with previous work on own-race bias, we observed a greater P100 response to White than Black faces; however, this racial bias was attenuated in the approach condition. These data suggest that rapid social perception may be flexible and can be modulated by motivational states. PMID:22661937

  16. Can Force Feedback and Science Learning Enhance the Effectiveness of Neuro-Rehabilitation? An Experimental Study on Using a Low-Cost 3D Joystick and a Virtual Visit to a Zoo

    PubMed Central

    Cappa, Paolo; Clerico, Andrea; Nov, Oded; Porfiri, Maurizio

    2013-01-01

    In this paper, we demonstrate that healthy adults respond differentially to the administration of force feedback and the presentation of scientific content in a virtual environment, where they interact with a low-cost haptic device. Subjects are tasked with controlling the movement of a cursor on a predefined trajectory that is superimposed on a map of New York City’s Bronx Zoo. The system is characterized in terms of a suite of objective indices quantifying the subjects’ dexterity in planning and generating the multijoint visuomotor tasks. We find that force feedback regulates the smoothness, accuracy, and duration of the subject’s movement, whereby converging or diverging force fields influence the range of variations of the hand speed. Finally, our findings provide preliminary evidence that using educational content increases subjects’ satisfaction. Improving the level of interest through the inclusion of learning elements can increase the time spent performing rehabilitation tasks and promote learning in a new context. PMID:24349562

  17. Teleoperation of Robonaut Using Finger Tracking

    NASA Technical Reports Server (NTRS)

    Champoux, Rachel G.; Luo, Victor

    2012-01-01

    With the advent of new finger tracking systems, the idea of a more expressive and intuitive user interface is being explored and implemented. One practical application for this new kind of interface is that of teleoperating a robot. For humanoid robots, a finger tracking interface is required due to the level of complexity in a human-like hand, where a joystick isn't accurate. Moreover, for some tasks, using one's own hands allows the user to communicate their intentions more effectively than other input. The purpose of this project was to develop a natural user interface for someone to teleoperate a robot that is elsewhere. Specifically, this was designed to control Robonaut on the international space station to do tasks too dangerous and/or too trivial for human astronauts. This interface was developed by integrating and modifying 3Gear's software, which includes a library of gestures and the ability to track hands. The end result is an interface in which the user can manipulate objects in real time in the user interface. then, the information is relayed to a simulator, the stand in for Robonaut, at a slight delay.

  18. An evaluation of the documented requirements of the SSP UIL and a review of commercial software packages for the development and testing of UIL prototypes

    NASA Technical Reports Server (NTRS)

    Gill, Esther Naomi

    1986-01-01

    A review was conducted of software packages currently on the market which might be integrated with the interface language and aid in reaching the objectives of customization, standardization, transparency, reliability, maintainability, language substitutions, expandability, portability, and flexibility. Recommendations are given for best choices in hardware and software acquisition for inhouse testing of these possible integrations. Software acquisition in the line of tools to aid expert-system development and/or novice program development, artificial intelligent voice technology and touch screen or joystick or mouse utilization as well as networking were recommended. Other recommendations concerned using the language Ada for the user interface language shell because of its high level of standardization, structure, and ability to accept and execute programs written in other programming languages, its DOD ownership and control, and keeping the user interface language simple so that multiples of users will find the commercialization of space within their realm of possibility which is, after all, the purpose of the Space Station.

  19. LudusScope: Accessible Interactive Smartphone Microscopy for Life-Science Education.

    PubMed

    Kim, Honesty; Gerber, Lukas Cyrill; Chiu, Daniel; Lee, Seung Ah; Cira, Nate J; Xia, Sherwin Yuyang; Riedel-Kruse, Ingmar H

    2016-01-01

    For centuries, observational microscopy has greatly facilitated biology education, but we still cannot easily and playfully interact with the microscopic world we see. We therefore developed the LudusScope, an accessible, interactive do-it-yourself smartphone microscopy platform that promotes exploratory stimulation and observation of microscopic organisms, in a design that combines the educational modalities of build, play, and inquire. The LudusScope's touchscreen and joystick allow the selection and stimulation of phototactic microorganisms such as Euglena gracilis with light. Organismal behavior is tracked and displayed in real time, enabling open and structured game play as well as scientific inquiry via quantitative experimentation. Furthermore, we used the Scratch programming language to incorporate biophysical modeling. This platform is designed as an accessible, low-cost educational kit for easy construction and expansion. User testing with both teachers and students demonstrates the educational potential of the LudusScope, and we anticipate additional synergy with the maker movement. Transforming observational microscopy into an interactive experience will make microbiology more tangible to society, and effectively support the interdisciplinary learning required by the Next Generation Science Standards.

  20. LudusScope: Accessible Interactive Smartphone Microscopy for Life-Science Education

    PubMed Central

    Kim, Honesty; Gerber, Lukas Cyrill; Chiu, Daniel; Lee, Seung Ah; Cira, Nate J.; Xia, Sherwin Yuyang; Riedel-Kruse, Ingmar H.

    2016-01-01

    For centuries, observational microscopy has greatly facilitated biology education, but we still cannot easily and playfully interact with the microscopic world we see. We therefore developed the LudusScope, an accessible, interactive do-it-yourself smartphone microscopy platform that promotes exploratory stimulation and observation of microscopic organisms, in a design that combines the educational modalities of build, play, and inquire. The LudusScope’s touchscreen and joystick allow the selection and stimulation of phototactic microorganisms such as Euglena gracilis with light. Organismal behavior is tracked and displayed in real time, enabling open and structured game play as well as scientific inquiry via quantitative experimentation. Furthermore, we used the Scratch programming language to incorporate biophysical modeling. This platform is designed as an accessible, low-cost educational kit for easy construction and expansion. User testing with both teachers and students demonstrates the educational potential of the LudusScope, and we anticipate additional synergy with the maker movement. Transforming observational microscopy into an interactive experience will make microbiology more tangible to society, and effectively support the interdisciplinary learning required by the Next Generation Science Standards. PMID:27706189

  1. Human machine interface to manually drive rhombic like vehicles in remote handling operations

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Lopes, Pedro; Vale, Alberto; Ventura, Rodrigo

    2015-07-01

    In the thermonuclear experimental reactor ITER, a vehicle named CTS is designed to transport a container with activated components inside the buildings. In nominal operations, the CTS is autonomously guided under supervision. However, in some unexpected situations, such as in rescue and recovery operations, the autonomous mode must be overridden and the CTS must be remotely guided by an operator. The CTS is a rhombic-like vehicle, with two drivable and steerable wheels along its longitudinal axis, providing omni-directional capabilities. The rhombic kinematics correspond to four control variables, which are difficult to manage in manual mode operation. This paper proposes amore » Human Machine Interface (HMI) to remotely guide the vehicle in manual mode. The proposed solution is implemented using a HMI with an encoder connected to a micro-controller and an analog 2-axis joystick. Experimental results were obtained comparing the proposed solution with other controller devices in different scenarios and using a software platform that simulates the kinematics and dynamics of the vehicle. (authors)« less

  2. Psychopaths lack the automatic avoidance of social threat: relation to instrumental aggression.

    PubMed

    Louise von Borries, Anna Katinka; Volman, Inge; de Bruijn, Ellen Rosalia Aloïs; Bulten, Berend Hendrik; Verkes, Robbert Jan; Roelofs, Karin

    2012-12-30

    Psychopathy (PP) is associated with marked abnormalities in social emotional behaviour, such as high instrumental aggression (IA). A crucial but largely ignored question is whether automatic social approach-avoidance tendencies may underlie this condition. We tested whether offenders with PP show lack of automatic avoidance tendencies, usually activated when (healthy) individuals are confronted with social threat stimuli (angry faces). We applied a computerized approach-avoidance task (AAT), where participants pushed or pulled pictures of emotional faces using a joystick, upon which the faces decreased or increased in size, respectively. Furthermore, participants completed an emotion recognition task which was used to control for differences in recognition of facial emotions. In contrast to healthy controls (HC), PP patients showed total absence of avoidance tendencies towards angry faces. Interestingly, those responses were related to levels of instrumental aggression and the (in)ability to experience personal distress (PD). These findings suggest that social performance in psychopaths is disturbed on a basic level of automatic action tendencies. The lack of implicit threat avoidance tendencies may underlie their aggressive behaviour. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

  3. On the role of exchange of power and information signals in control and stability of the human-robot interaction

    NASA Technical Reports Server (NTRS)

    Kazerooni, H.

    1991-01-01

    A human's ability to perform physical tasks is limited, not only by his intelligence, but by his physical strength. If, in an appropriate environment, a machine's mechanical power is closely integrated with a human arm's mechanical power under the control of the human intellect, the resulting system will be superior to a loosely integrated combination of a human and a fully automated robot. Therefore, we must develop a fundamental solution to the problem of 'extending' human mechanical power. The work presented here defines 'extenders' as a class of robot manipulators worn by humans to increase human mechanical strength, while the wearer's intellect remains the central control system for manipulating the extender. The human, in physical contact with the extender, exchanges power and information signals with the extender. The aim is to determine the fundamental building blocks of an intelligent controller, a controller which allows interaction between humans and a broad class of computer-controlled machines via simultaneous exchange of both power and information signals. The prevalent trend in automation has been to physically separate the human from the machine so the human must always send information signals via an intermediary device (e.g., joystick, pushbutton, light switch). Extenders, however are perfect examples of self-powered machines that are built and controlled for the optimal exchange of power and information signals with humans. The human wearing the extender is in physical contact with the machine, so power transfer is unavoidable and information signals from the human help to control the machine. Commands are transferred to the extender via the contact forces and the EMG signals between the wearer and the extender. The extender augments human motor ability without accepting any explicit commands: it accepts the EMG signals and the contact force between the person's arm and the extender, and the extender 'translates' them into a desired position. In this unique configuration, mechanical power transfer between the human and the extender occurs because the human is pushing against the extender. The extender transfers to the human's hand, in feedback fashion, a scaled-down version of the actual external load which the extender is manipulating. This natural feedback force on the human's hand allows him to 'feel' a modified version of the external forces on the extender. The information signals from the human (e.g., EMG signals) to the computer reflect human cognitive ability, and the power transfer between the human and the machine (e.g., physical interaction) reflects human physical ability. Thus the information transfer to the machine augments cognitive ability, and the power transfer augments motor ability. These two actions are coupled through the human cognitive/motor dynamic behavior. The goal is to derive the control rules for a class of computer-controlled machines that augment human physical and cognitive abilities in certain manipulative tasks.

  4. Motorized fusion guided prostate biopsy: phantom study

    NASA Astrophysics Data System (ADS)

    Seifabadi, Reza; Xu, Sheng; Aalamifar, Fereshteh; Pinto, Peter; Wood, Bradford J.

    2017-03-01

    Purpose: Fusion of Magnetic Resonance Imaging (MRI) with intraoperative real-time Ultrasound (US) during prostate biopsy has significantly improved the sensitivity of transrectal ultrasound (TRUS) guided cancer detection. Currently, sweeping of the TRUS probe to build a 3D volume as part of the fusion process and the TRUS probe manipulation for needle guidance are both done manually. A motorized, joystick controlled, probe holder was custom fabricated that can potentially reduce inter-operator variability, provide standardization of needle placement, improve repeatability and uniformity of needle placement, which may have impacts upon the learning curve after clinical deployment of this emerging approach. Method: a 2DOF motorized probe holder was designed to provide translation and rotation of a triplane TRUS end firing probe for prostate biopsy. The probe holder was joystick controlled and can assist manipulation of the probe during needle insertion as well as in acquiring a smoother US 2D to 3D sweep in which the 3D US volume for fusion is built. A commercial MRI-US fusion platform was used. Three targets were specified on MR image of a commercial prostate phantom. After performing the registration, two operators performed targeting, once manually and once with the assistance of the motorized probe holder. They repeated these tasks 5 times resulting in a total of 30 targeting events. Time of completion and mechanical error i.e. distance of the target from the needle trajectory in the software user interface were measured. Repeatability in reaching a given target in a systematic and consistent way was measured using a scatter plot showing all targets in the US coordinate system. Pearson product-moment correlation coefficient (PPMCC) was used to demonstrate the probe steadiness during targeting. Results: the completion time was 25+/-17 sec, 25+/-24 sec, and 27+/-15 sec for free hand and 24+/-10 sec, 22.5+/-10 sec, and 37+/-10 sec for motorized insertion, for target 1, 2, and 3, respectively. The mechanical error was 0.75+/-0.4 mm, 0.45+/-0.4 mm, and 0.55+/-0.4 mm, for free hand approach while it was 1.0+/-0.57 mm, 0.45+/-0.4 mm, and 0.35+/-0.25 mm, for motorized approach, for target 1, 2, and 3, respectively. PPMCC remained almost at 1.0 for the motorized approach while having a variation between 0.9 and 1.0 for the free hand approach. Conclusions: motorized fusion guided prostate biopsy in a phantom study was feasible and non-inferior or comparable to the free hand manual approach in terms of accuracy and speed of targeting, while being superior in terms of repeatability and steadiness.

  5. Improving land vehicle situational awareness using a distributed aperture system

    NASA Astrophysics Data System (ADS)

    Fortin, Jean; Bias, Jason; Wells, Ashley; Riddle, Larry; van der Wal, Gooitzen; Piacentino, Mike; Mandelbaum, Robert

    2005-05-01

    U.S. Army Research, Development, and Engineering Command (RDECOM) Communications Electronics Research, Development and Engineering Center (CERDEC) Night Vision and Electronic Sensors Directorate (NVESD) has performed early work to develop a Distributed Aperture System (DAS). The DAS aims at improving the situational awareness of armored fighting vehicle crews under closed-hatch conditions. The concept is based on a plurality of sensors configured to create a day and night dome of surveillance coupled with heads up displays slaved to the operator's head to give a "glass turret" feel. State-of-the-art image processing is used to produce multiple seamless hemispherical views simultaneously available to the vehicle commander, crew members and dismounting infantry. On-the-move automatic cueing of multiple moving/pop-up low silhouette threats is also done with the possibility to save/revisit/share past events. As a first step in this development program, a contract was awarded to United Defense to further develop the Eagle VisionTM system. The second-generation prototype features two camera heads, each comprising four high-resolution (2048x1536) color sensors, and each covering a field of view of 270°hx150°v. High-bandwidth digital links interface the camera heads with a field programmable gate array (FPGA) based custom processor developed by Sarnoff Corporation. The processor computes the hemispherical stitch and warp functions required for real-time, low latency, immersive viewing (360°hx120°v, 30° down) and generates up to six simultaneous extended graphics array (XGA) video outputs for independent display either on a helmet-mounted display (with associated head tracking device) or a flat panel display (and joystick). The prototype is currently in its last stage of development and will be integrated on a vehicle for user evaluation and testing. Near-term improvements include the replacement of the color camera heads with a pixel-level fused combination of uncooled long wave infrared (LWIR) and low light level intensified imagery. It is believed that the DAS will significantly increase situational awareness by providing the users with a day and night, wide area coverage, immersive visualization capability.

  6. Two-Armed, Mobile, Sensate Research Robot

    NASA Technical Reports Server (NTRS)

    Engelberger, J. F.; Roberts, W. Nelson; Ryan, David J.; Silverthorne, Andrew

    2004-01-01

    The Anthropomorphic Robotic Testbed (ART) is an experimental prototype of a partly anthropomorphic, humanoid-size, mobile robot. The basic ART design concept provides for a combination of two-armed coordination, tactility, stereoscopic vision, mobility with navigation and avoidance of obstacles, and natural-language communication, so that the ART could emulate humans in many activities. The ART could be developed into a variety of highly capable robotic assistants for general or specific applications. There is especially great potential for the development of ART-based robots as substitutes for live-in health-care aides for home-bound persons who are aged, infirm, or physically handicapped; these robots could greatly reduce the cost of home health care and extend the term of independent living. The ART is a fully autonomous and untethered system. It includes a mobile base on which is mounted an extensible torso topped by a head, shoulders, and two arms. All subsystems of the ART are powered by a rechargeable, removable battery pack. The mobile base is a differentially- driven, nonholonomic vehicle capable of a speed >1 m/s and can handle a payload >100 kg. The base can be controlled manually, in forward/backward and/or simultaneous rotational motion, by use of a joystick. Alternatively, the motion of the base can be controlled autonomously by an onboard navigational computer. By retraction or extension of the torso, the head height of the ART can be adjusted from 5 ft (1.5 m) to 6 1/2 ft (2 m), so that the arms can reach either the floor or high shelves, or some ceilings. The arms are symmetrical. Each arm (including the wrist) has a total of six rotary axes like those of the human shoulder, elbow, and wrist joints. The arms are actuated by electric motors in combination with brakes and gas-spring assists on the shoulder and elbow joints. The arms are operated under closed-loop digital control. A receptacle for an end effector is mounted on the tip of the wrist and contains a force-and-torque sensor that provides feedback for force (compliance) control of the arm. The end effector could be a tool or a robot hand, depending on the application.

  7. A Transfer of Training Study of Control Loader Dynamics

    NASA Technical Reports Server (NTRS)

    Cardullo, Frank M.; Stanco, Anthony A.; Kelly, Lon C.; Houck, Jacob A.; Grube, Richard C.

    2011-01-01

    The control inceptor used in a simulated vehicle is an important part in maintaining the fidelity of a simulation. The force feedback provided by the control inceptor gives the operator important cues to maintain adequate performance. The dynamics of a control inceptor are typically based on a second order spring mass damper system with damping, force gradient, breakout force, and natural frequency parameters. Changing these parameters can have a great effect on pilot or driver control of the vehicle. The neuromuscular system has a very important role in manipulating the control inceptor within a vehicle. Many studies by McRuer, Aponso, and Hess have dealt with modeling the neuromuscular system and quantifying the effects of a high fidelity control loader as compared to a low fidelity control loader. Humans are adaptive in nature and their control behavior changes based on different control loader dynamics. Humans will change their control behavior to maintain tracking bandwidth and minimize tracking error. This paper reports on a quasi-transfer of training experiment which was performed at the NASA Langley Research Center. The quasi transfer of training study used a high fidelity control loader and a low fidelity control loader. Subjects trained in both simulations and then were transferred to the high fidelity control loader simulation. The parameters for the high fidelity control loader were determined from the literature. The low fidelity control loader parameters were found through testing of a simple computer joystick. A disturbance compensatory task is employed. The compensatory task involves implementing a simple horizon out the window display. A disturbance consisting of a sum of sines is used. The task consists of the subject compensating for the disturbance on the roll angle of the aircraft. The vehicle dynamics are represented as 1/s and 1/s2. The subject will try to maintain level flight throughout the experiment. The subjects consist of non-pilots to remove any effects of pilot experience. First, this paper discusses the implementation of the disturbance compensation task. Second, the high and low fidelity parameters used within the experiment are presented. Finally, an explanation of results from the experiments is presented.

  8. Evaluation of the JACO robotic arm: clinico-economic study for powered wheelchair users with upper-extremity disabilities.

    PubMed

    Maheu, Veronique; Frappier, Julie; Archambault, Philippe S; Routhier, François

    2011-01-01

    Many activities of daily living, such as picking up glasses, holding a fork or opening a door, which most people do without thinking, can become insurmountable for people who have upper extremity disabilities. The alternative to asking for human help is to use some assistive devices to compensate their loss of mobility; however, many of those devices are limited in terms of functionality. Robotics may provide a better approach for the development of assistive devices, by allowing greater functionality. In this paper, we present results of a study (n=31) which objectives were to evaluate the efficacy of a new joystick-controlled seven-degree of freedom robotic manipulator and assess its potential economic benefits. Results show that JACO is easy to use as the majority of the participants were able to accomplish the testing tasks on their first attempt. The economic model results inferred that the use of the JACO arm system could potentially reduce caregiving time by 41%. These study results are expected to provide valuable data for interested parties, such as individuals with disabilities, their family or caregivers. © 2011 IEEE

  9. Modifying Automatic Approach Action Tendencies in Individuals with Elevated Social Anxiety Symptoms

    PubMed Central

    Taylor, Charles T.; Amir, Nader

    2012-01-01

    Research suggests that social anxiety is associated with a reduced approach orientation for positive social cues. In the current study we examined the effect of experimentally manipulating automatic approach action tendencies on the social behavior of individuals with elevated social anxiety symptoms. The experimental paradigm comprised a computerized Approach Avoidance Task (AAT) in which participants responded to pictures of faces conveying positive or neutral emotional expressions by pulling a joystick toward themselves (approach) or by moving it to the right (sideways control). Participants were randomly assigned to complete an AAT designed to increase approach tendencies for positive social cues by pulling these cues toward themselves on the majority of trials, or to a control condition in which there was no contingency between the arm movement direction and picture type. Following the manipulation, participants took part in a relationship-building task with a trained confederate. Results revealed that participants trained to approach positive stimuli displayed greater social approach behaviors during the social interaction and elicited more positive reactions from their partner compared to participants in the control group. These findings suggest that modifying automatic approach tendencies may facilitate engagement in the types of social approach behaviors that are important for relationship development. PMID:22728645

  10. Decoding position, velocity, or goal: does it matter for brain-machine interfaces?

    PubMed

    Marathe, A R; Taylor, D M

    2011-04-01

    Arm end-point position, end-point velocity, and the intended final location or 'goal' of a reach have all been decoded from cortical signals for use in brain-machine interface (BMI) applications. These different aspects of arm movement can be decoded from the brain and used directly to control the position, velocity, or movement goal of a device. However, these decoded parameters can also be remapped to control different aspects of movement, such as using the decoded position of the hand to control the velocity of a device. People easily learn to use the position of a joystick to control the velocity of an object in a videogame. Similarly, in BMI systems, the position, velocity, or goal of a movement could be decoded from the brain and remapped to control some other aspect of device movement. This study evaluates how easily people make transformations between position, velocity, and reach goal in BMI systems. It also evaluates how different amounts of decoding error impact on device control with and without these transformations. Results suggest some remapping options can significantly improve BMI control. This study provides guidance on what remapping options to use when various amounts of decoding error are present.

  11. A novel training approach to activate alternative behaviors for smoking in depressed smokers.

    PubMed

    Kopetz, Catalina; MacPherson, Laura; Mitchell, Avery D; Houston-Ludlam, Alexandra N; Wiers, Reinout W

    2017-02-01

    The current research developed and tested a novel training strategy to alter the implicit associations between alternative behaviors to smoking and negative affect, and explored its effects on depressive symptoms and on smoking behavior as part of a quit attempt. Using a joystick, participants identified as smokers with depressive symptoms were trained to approach alternative behaviors to smoking in the context of negative affect. Specifically, in the experimental condition, participants were trained to avoid smoking-related targets and to approach alternative activities. In the control condition, participants pushed and pulled an equal amount of smoking and alternative activity-related targets. Compared with the participants in the control condition, those in the experimental condition showed an increase in the accessibility of the alternative activity relative to smoking and a decrease in depressive symptoms. Smoking outcomes did not differ significantly across the 2 conditions. Taken together these results indicate that the value of alternative behaviors to smoking can be modified in the lab without participants' conscious intentions with implications for depressive symptomatology. Future research is required to explore the impact of such training on smoking outcomes. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

  12. Comparative evaluation of user interfaces for robot-assisted laser phonomicrosurgery.

    PubMed

    Dagnino, Giulio; Mattos, Leonardo S; Becattini, Gabriele; Dellepiane, Massimo; Caldwell, Darwin G

    2011-01-01

    This research investigates the impact of three different control devices and two visualization methods on the precision, safety and ergonomics of a new medical robotic system prototype for assistive laser phonomicrosurgery. This system allows the user to remotely control the surgical laser beam using either a flight simulator type joystick, a joypad, or a pen display system in order to improve the traditional surgical setup composed by a mechanical micromanipulator coupled with a surgical microscope. The experimental setup and protocol followed to obtain quantitative performance data from the control devices tested are fully described here. This includes sets of path following evaluation experiments conducted with ten subjects with different skills, for a total of 700 trials. The data analysis method and experimental results are also presented, demonstrating an average 45% error reduction when using the joypad and up to 60% error reduction when using the pen display system versus the standard phonomicrosurgery setup. These results demonstrate the new system can provide important improvements in terms of surgical precision, ergonomics and safety. In addition, the evaluation method presented here is shown to support an objective selection of control devices for this application.

  13. Dividing Attention Between Tasks: Testing Whether Explicit Payoff Functions Elicit Optimal Dual-Task Performance.

    PubMed

    Farmer, George D; Janssen, Christian P; Nguyen, Anh T; Brumby, Duncan P

    2018-04-01

    We test people's ability to optimize performance across two concurrent tasks. Participants performed a number entry task while controlling a randomly moving cursor with a joystick. Participants received explicit feedback on their performance on these tasks in the form of a single combined score. This payoff function was varied between conditions to change the value of one task relative to the other. We found that participants adapted their strategy for interleaving the two tasks, by varying how long they spent on one task before switching to the other, in order to achieve the near maximum payoff available in each condition. In a second experiment, we show that this behavior is learned quickly (within 2-3 min over several discrete trials) and remained stable for as long as the payoff function did not change. The results of this work show that people are adaptive and flexible in how they prioritize and allocate attention in a dual-task setting. However, it also demonstrates some of the limits regarding people's ability to optimize payoff functions. Copyright © 2017 The Authors. Cognitive Science published by Wiley Periodicals, Inc. on behalf of Cognitive Science Society.

  14. BRIDGE - Behavioural reaching interfaces during daily antigravity activities through upper limb exoskeleton: Preliminary results.

    PubMed

    Gandolla, Marta; Costa, Andrea; Aquilante, Lorenzo; Gfoehler, Margit; Puchinger, Markus; Braghin, Francesco; Pedrocchi, Alessandra

    2017-07-01

    People with neuromuscular diseases such as muscular dystrophy experience a distributed and evolutive weakness in the whole body. Recent technological developments have changed the daily life of disabled people strongly improving the perceived quality of life, mostly concentrating on powered wheelchairs, so to assure autonomous mobility and respiratory assistance, essential for survival. The key concept of the BRIDGE project is to contrast the everyday experience of losing functions by providing them of a system able to exploit the best their own residual capabilities in arm movements so to keep them functional and autonomous as much as possible. BRIDGE is composed by a light, wearable and powered five degrees of freedom upper limb exoskeleton under the direct control of the user through a joystick or gaze control. An inverse kinematic model allows to determine joints position so to track patient desired hand position. BRIDGE prototype has been successfully tested in simulation environment, and by a small group of healthy volunteers. Preliminary results show a good tracking performance of the implemented control scheme. The interaction procedure was easy to understand, and the interaction with the system was successful.

  15. Augmented reality for breast imaging.

    PubMed

    Rancati, Alberto; Angrigiani, Claudio; Nava, Maurizio B; Catanuto, Giuseppe; Rocco, Nicola; Ventrice, Fernando; Dorr, Julio

    2018-06-01

    Augmented reality (AR) enables the superimposition of virtual reality reconstructions onto clinical images of a real patient, in real time. This allows visualization of internal structures through overlying tissues, thereby providing a virtual transparency vision of surgical anatomy. AR has been applied to neurosurgery, which utilizes a relatively fixed space, frames, and bony references; the application of AR facilitates the relationship between virtual and real data. Augmented breast imaging (ABI) is described. Breast MRI studies for breast implant patients with seroma were performed using a Siemens 3T system with a body coil and a four-channel bilateral phased-array breast coil as the transmitter and receiver, respectively. Gadolinium was injected as a contrast agent (0.1 mmol/kg at 2 mL/s) using a programmable power injector. Dicom formatted images data from 10 MRI cases of breast implant seroma and 10 MRI cases with T1-2 N0 M0 breast cancer, were imported and transformed into augmented reality images. ABI demonstrated stereoscopic depth perception, focal point convergence, 3D cursor use, and joystick fly-through. ABI can improve clinical outcomes, providing an enhanced view of the structures to work on. It should be further studied to determine its utility in clinical practice.

  16. Production of isometric forces during sustained acceleration.

    PubMed

    Sand, D P; Girgenrath, M; Bock, O; Pongratz, H

    2003-06-01

    The operation of high-performance aircraft requires pilots to apply finely graded forces on controls. Since they are often exposed to high levels of acceleration in flight, we investigated to what extent this ability is degraded in such an environment. Twelve healthy non-pilot volunteers were seated in the gondola of a centrifuge and their performance was tested at normal gravity (1 G) and while exposed to sustained forces of 1.5 G and 3 G oriented from head to foot (+Gz). Using an isometric joystick, they attempted to produce force vectors with specific lengths and directions commanded in random order by a visual display. Acceleration had substantial effects on the magnitude of produced force. Compared with 1 G, maximum produced force was about 2 N higher at 1.5 G and about 10 N higher at 3 G. The size of this effect was constant across the different magnitudes, but varied with the direction of the prescribed force. Acceleration degrades control of force production. This finding may indicate that the motor system misinterprets the unusual gravitoinertial environment and/or that proprioceptive feedback is degraded due to increased muscle tone. The production of excessive isometric force could affect the safe operation of high-performance aircraft.

  17. An autonomous sensor module based on a legacy CCTV camera

    NASA Astrophysics Data System (ADS)

    Kent, P. J.; Faulkner, D. A. A.; Marshall, G. F.

    2016-10-01

    A UK MoD funded programme into autonomous sensors arrays (SAPIENT) has been developing new, highly capable sensor modules together with a scalable modular architecture for control and communication. As part of this system there is a desire to also utilise existing legacy sensors. The paper reports upon the development of a SAPIENT-compliant sensor module using a legacy Close-Circuit Television (CCTV) pan-tilt-zoom (PTZ) camera. The PTZ camera sensor provides three modes of operation. In the first mode, the camera is automatically slewed to acquire imagery of a specified scene area, e.g. to provide "eyes-on" confirmation for a human operator or for forensic purposes. In the second mode, the camera is directed to monitor an area of interest, with zoom level automatically optimized for human detection at the appropriate range. Open source algorithms (using OpenCV) are used to automatically detect pedestrians; their real world positions are estimated and communicated back to the SAPIENT central fusion system. In the third mode of operation a "follow" mode is implemented where the camera maintains the detected person within the camera field-of-view without requiring an end-user to directly control the camera with a joystick.

  18. Decoding position, velocity, or goal: Does it matter for brain-machine interfaces?

    NASA Astrophysics Data System (ADS)

    Marathe, A. R.; Taylor, D. M.

    2011-04-01

    Arm end-point position, end-point velocity, and the intended final location or 'goal' of a reach have all been decoded from cortical signals for use in brain-machine interface (BMI) applications. These different aspects of arm movement can be decoded from the brain and used directly to control the position, velocity, or movement goal of a device. However, these decoded parameters can also be remapped to control different aspects of movement, such as using the decoded position of the hand to control the velocity of a device. People easily learn to use the position of a joystick to control the velocity of an object in a videogame. Similarly, in BMI systems, the position, velocity, or goal of a movement could be decoded from the brain and remapped to control some other aspect of device movement. This study evaluates how easily people make transformations between position, velocity, and reach goal in BMI systems. It also evaluates how different amounts of decoding error impact on device control with and without these transformations. Results suggest some remapping options can significantly improve BMI control. This study provides guidance on what remapping options to use when various amounts of decoding error are present.

  19. Design considerations to improve cognitive ergonomic issues of unmanned vehicle interfaces utilizing video game controllers.

    PubMed

    Oppold, P; Rupp, M; Mouloua, M; Hancock, P A; Martin, J

    2012-01-01

    Unmanned (UAVs, UCAVs, and UGVs) systems still have major human factors and ergonomic challenges related to the effective design of their control interface systems, crucial to their efficient operation, maintenance, and safety. Unmanned system interfaces with a human centered approach promote intuitive interfaces that are easier to learn, and reduce human errors and other cognitive ergonomic issues with interface design. Automation has shifted workload from physical to cognitive, thus control interfaces for unmanned systems need to reduce mental workload on the operators and facilitate the interaction between vehicle and operator. Two-handed video game controllers provide wide usability within the overall population, prior exposure for new operators, and a variety of interface complexity levels to match the complexity level of the task and reduce cognitive load. This paper categorizes and provides taxonomy for 121 haptic interfaces from the entertainment industry that can be utilized as control interfaces for unmanned systems. Five categories of controllers were based on the complexity of the buttons, control pads, joysticks, and switches on the controller. This allows the selection of the level of complexity needed for a specific task without creating an entirely new design or utilizing an overly complex design.

  20. Using Unconstrained Tongue Motion as an Alternative Control Mechanism for Wheeled Mobility

    PubMed Central

    Huo, Xueliang; Ghovanloo, Maysam

    2015-01-01

    Tongue drive system (TDS) is a tongue-operated, minimally invasive, unobtrusive, noncontact, and wireless assistive technology that infers users’ intentions by detecting and classifying their voluntary tongue motions, and translating them to user-defined commands. We have developed customized interface circuitry between an external TDS (eTDS) prototype and a commercial powered wheelchair (PWC) as well as three control strategies to evaluate the tongue motion as an alternative control input for wheeled mobility. We tested the eTDS performance in driving PWCs on 12 able-bodied human subjects, of which 11 were novice. The results showed that all subjects could complete navigation tasks by operating the PWC using their tongue motions. Despite little prior experience, the average time using the eTDS and the tongue was only approximately three times longer than using a joystick and the fingers. Navigation time was strongly dependant on the number of issued commands, which reduced by gaining experience. Particularly, the unintended issued commands (the Midas touch problem) were rare, demonstrating the effectiveness of the tongue tracking and external magnetic field cancellation algorithms as well as the safety of the TDS for wheeled mobility. PMID:19362901

  1. Using unconstrained tongue motion as an alternative control mechanism for wheeled mobility.

    PubMed

    Huo, Xueliang; Ghovanloo, Maysam

    2009-06-01

    Tongue drive system (TDS) is a tongue-operated, minimally invasive, unobtrusive, noncontact, and wireless assistive technology that infers users' intentions by detecting and classifying their voluntary tongue motions, and translating them to user-defined commands. We have developed customized interface circuitry between an external TDS (eTDS) prototype and a commercial powered wheelchair (PWC) as well as three control strategies to evaluate the tongue motion as an alternative control input for wheeled mobility. We tested the eTDS performance in driving PWCs on 12 able-bodied human subjects, of which 11 were novice. The results showed that all subjects could complete navigation tasks by operating the PWC using their tongue motions. Despite little prior experience, the average time using the eTDS and the tongue was only approximately three times longer than using a joystick and the fingers. Navigation time was strongly dependant on the number of issued commands, which reduced by gaining experience. Particularly, the unintended issued commands (the Midas touch problem) were rare, demonstrating the effectiveness of the tongue tracking and external magnetic field cancellation algorithms as well as the safety of the TDS for wheeled mobility.

  2. Gesture-Based Robot Control with Variable Autonomy from the JPL Biosleeve

    NASA Technical Reports Server (NTRS)

    Wolf, Michael T.; Assad, Christopher; Vernacchia, Matthew T.; Fromm, Joshua; Jethani, Henna L.

    2013-01-01

    This paper presents a new gesture-based human interface for natural robot control. Detailed activity of the user's hand and arm is acquired via a novel device, called the BioSleeve, which packages dry-contact surface electromyography (EMG) and an inertial measurement unit (IMU) into a sleeve worn on the forearm. The BioSleeve's accompanying algorithms can reliably decode as many as sixteen discrete hand gestures and estimate the continuous orientation of the forearm. These gestures and positions are mapped to robot commands that, to varying degrees, integrate with the robot's perception of its environment and its ability to complete tasks autonomously. This flexible approach enables, for example, supervisory point-to-goal commands, virtual joystick for guarded teleoperation, and high degree of freedom mimicked manipulation, all from a single device. The BioSleeve is meant for portable field use; unlike other gesture recognition systems, use of the BioSleeve for robot control is invariant to lighting conditions, occlusions, and the human-robot spatial relationship and does not encumber the user's hands. The BioSleeve control approach has been implemented on three robot types, and we present proof-of-principle demonstrations with mobile ground robots, manipulation robots, and prosthetic hands.

  3. Simultaneous refraction measurement and OCT axial biometry of the eye during accommodation (Conference Presentation)

    NASA Astrophysics Data System (ADS)

    De Freitas, Carolina; Hernandez, Victor M.; Ruggeri, Marco; Durkee, Heather A.; Williams, Siobhan; Gregori, Giovanni; Ho, Arthur; Manns, Fabrice; Parel, Jean-Marie

    2016-03-01

    The purpose of this project is to design and evaluate a system that will enable objective assessment of the optical accommodative response in real-time while acquiring axial biometric information. The system combines three sub-systems which were integrated and mounted on a joystick x-y-z adjustable modified slit-lamp base to facilitate alignment and data acquisition: (1) a Shack-Hartmann wavefront sensor for dynamic refraction measurement, provided software calculates sphere, cylinder and axis values, (2) an extended-depth Optical Coherence Tomography (OCT) system using an optical switch records high-resolution cross-sectional images across the length of the eye, from which, dynamic axial biometry (corneal thickness, anterior chamber depth, crystalline lens thickness and vitreous depth) can be extracted, and (3) a modified dual-channel accommodation stimulus unit based on the Badal optometer for providing a step change in accommodative stimulus. The prototypal system is capable of taking simultaneous measurements of both the optical and the mechanical response of lens accommodation. These measurements can provide insight into correlating changes in lens shape with changes in lens power and ocular refraction and ultimately provide a more comprehensive understanding of accommodation, presbyopia and an objective assessment of presbyopia correction techniques.

  4. Social approach and avoidance behaviour for negative emotions is modulated by endogenous oxytocin and paranoia in schizophrenia.

    PubMed

    Brown, Elliot C; Tas, Cumhur; Kuzu, Duygu; Esen-Danaci, Aysen; Roelofs, Karin; Brüne, Martin

    2014-11-30

    Patients with schizophrenia suffer from dysfunctional social behaviour. Social approach and avoidance (AA) has been associated with motor responses, as the affective valence and gaze direction of facial stimuli can bias push and pull motor tendencies. The aim of this study was to investigate the role of endogenous oxytocin in social AA behaviour in schizophrenia. Basal plasma oxytocin levels were collected from 28 patients who were then given a joystick-based Approach-Avoidance Task (AAT). Reaction times were recorded and AAT effect scores calculated for responses to happy and angry faces, which either had direct or averted gaze. Individual differences in basal oxytocin had a significant relationship with AAT responses, and patients with higher levels of oxytocin tended to avoid angry faces more. Furthermore, greater avoidance of angry faces was correlated with more severe psychotic (positive and general) symptoms and greater paranoia. This suggests that the endogenous effects of oxytocin may be specific to the interpretation of negative threatening emotions in schizophrenia patients, and also provides evidence that psychotic symptoms and paranoia can impact on social AA behaviour by heightening threat avoidance. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

  5. Neural correlates of social approach and withdrawal in patients with major depression.

    PubMed

    Derntl, Birgit; Seidel, Eva-Maria; Eickhoff, Simon B; Kellermann, Thilo; Gur, Ruben C; Schneider, Frank; Habel, Ute

    2011-01-01

    Successful human interaction is based on correct recognition, interpretation, and appropriate reaction to facial affect. In depression, social skill deficits are among the most restraining symptoms leading to social withdrawal, thereby aggravating social isolation and depressive affect. Dysfunctional approach and withdrawal tendencies to emotional stimuli have been documented, but the investigation of their neural underpinnings has received limited attention. We performed an fMRI study including 15 depressive patients and 15 matched, healthy controls. All subjects performed two tasks, an implicit joystick task as well as an explicit rating task, both using happy, neutral, and angry facial expressions. Behavioral data analysis indicated a significant group effect, with depressed patients showing more withdrawal than controls. Analysis of the functional data revealed significant group effects for both tasks. Among other regions, we observed significant group differences in amygdala activation, with patients showing less response particularly during approach to happy faces. Additionally, significant correlations of amygdala activation with psychopathology emerged, suggesting that more pronounced symptoms are accompanied by stronger decreases of amygdala activation. Hence, our results demonstrate that depressed patients show dysfunctional social approach and withdrawal behavior, which in turn may aggravate the disorder by negative social interactions contributing to isolation and reinforcing cognitive biases.

  6. The development of a test system for investigating the performances of personal aerosol samplers under actual workplace conditions.

    PubMed

    Botham, R A; Hughson, G W; Vincent, J H; Mark, D

    1991-10-01

    The performances of new "total" aerosol samplers for use in workplaces are required to match the inhalability criteria as contained in the latest recommendations of the International Standards Organization (ISO) and the American Conference of Governmental Industrial Hygienists (ACGIH). In the past, practical evaluations have been carried out under idealized conditions in wind tunnels, and there is now the need to extend these to more realistic workplace conditions. This paper describes a new test system that was designed and built for this purpose. It consisted of a life-size mannequin mounted on a trolley so that it can be taken to and wheeled around in workplaces. The mannequin itself incorporated a robotic arm so that, under joystick control, it can be made to simulate a range of worker movements, orientations, and attitudes. An electronically controlled, compact breathing machine provided a range of typical breathing parameters for the mannequin. The pump also provided air movement for a number of personal samplers that were mounted on the torso of the mannequin and tested in that position. Sampler performance should be assessed by comparing directly the aerosol collected by the sampler with that inhaled by the mannequin (and collected on filters inside the head).

  7. Multi-limbed locomotion systems for space construction and maintenance

    NASA Technical Reports Server (NTRS)

    Waldron, K. J.; Klein, C. A.

    1987-01-01

    A well developed technology of coordination of multi-limbed locomotory systems is now available. Results from a NASA sponsored study of several years ago are presented. This was a simulation study of a three-limbed locomotion/manipulation system. Each limb had six degrees of freedom and could be used either as a locomotory grasping hand-holds, or as a manipulator. The focus of the study was kinematic coordination algorithms. The presentation will also include very recent results from the Adaptive Suspension Vehicle Project. The Adaptive Suspension Vehicle (ASV) is a legged locomotion system designed for terrestrial use which is capable of operating in completely unstructured terrain in either a teleoperated or operator-on-board mode. Future development may include autonomous operation. The ASV features a very advanced coordination and control system which could readily be adapted to operation in space. An inertial package with a vertical gyro, and rate gyros and accelerometers on three orthogonal axes provides body position information at high bandwidth. This is compared to the operator's commands, injected via a joystick to provide a commanded force system on the vehicle's body. This system is, in turn, decomposed by a coordination algorithm into force commands to those legs which are in contact with the ground.

  8. Design, Prototyping and Control of a Flexible Cystoscope for Biomedical Applications

    NASA Astrophysics Data System (ADS)

    Sozer, Canberk; Ghorbani, Morteza; Alcan, Gokhan; Uvet, Huseyin; Unel, Mustafa; Kosar, Ali

    2017-07-01

    Kidney stone and prostate hyperplasia are very common urogenital diseases all over the world. To treat these diseases, one of the ESWL (Extracorporeal Shock Wave Lithotripsy), PCNL (Percutaneous Nephrolithotomy), cystoscopes or open surgery techniques can be used. Cystoscopes named devices are used for in-vivo intervention. A flexible or rigid cystoscope device is inserted into human body and operates on interested area. In this study, a flexible cystoscope prototype has been developed. The prototype is able to bend up to ±40°in X and Y axes, has a hydrodynamic cavitation probe for rounding sharp edges of kidney stone or resection of the filled prostate with hydrodynamic cavitation method and contains a waterproof medical camera to give visual feedback to the operator. The operator steers the flexible end-effector via joystick toward target region. This paper presents design, manufacturing, control and experimental setup of the tendon driven flexible cystoscope prototype. The prototype is 10 mm in outer diameter, 70 mm in flexible part only and 120 mm in total length with flexible part and rigid tube. The experimental results show that the prototype bending mechanism, control system, manufactured prototype parts and experimental setup function properly. A small piece of real kidney stone was broken in targeted area.

  9. Anxiety provocation and measurement using virtual reality in patients with obsessive-compulsive disorder.

    PubMed

    Kim, Kwanguk; Kim, Chan-Hyung; Cha, Kyung Ryeol; Park, Junyoung; Han, Kiwan; Kim, Yun Ki; Kim, Jae-Jin; Kim, In Young; Kim, Sun I

    2008-12-01

    The current study is a preliminary test of a virtual reality (VR) anxiety-provoking tool using a sample of participants with obsessive-compulsive disorder (OCD). The tasks were administrated to 33 participants with OCD and 30 healthy control participants. In the VR task, participants navigated through a virtual environment using a joystick and head-mounted display. The virtual environment consisted of three phases: training, distraction, and the main task. After the training and distraction phases, participants were allowed to check (a common OCD behavior) freely, as they would in the real world, and a visual analogy scale of anxiety was recorded during VR. Participants' anxiety in the virtual environment was measured with a validated measure of psychiatric symptoms and functions and analyzed with a VR questionnaire. Results revealed that those with OCD had significantly higher anxiety in the virtual environment than did healthy controls, and the decreased ratio of anxiety in participants with OCD was also higher than that of healthy controls. Moreover, the degree of anxiety of an individual with OCD was positively correlated with a his or her symptom score and immersive tendency score. These results suggest the possibility that VR technology has a value as an anxiety-provoking or treatment tool for OCD.

  10. Approach and avoidance towards aggressive stimuli and its relation to reactive and proactive aggression.

    PubMed

    Lobbestael, Jill; Cousijn, Janna; Brugman, Suzanne; Wiers, Reinout W

    2016-06-30

    This study assessed the association between indirectly measured behavioural approach- and avoidance-related tendencies on the one hand, and reactive versus proactive aggression on the other hand. Reactive aggression (i.e. the impulsive, anger-driven aggression expressed in response to threatening stimuli) was differentiated from proactive aggression (i.e. the more controlled aggression motivated towards obtaining specific goals). A mixed sample of 118 patients and healthy controls filled out a self-report measure to assess their degree of reactive and proactive aggression, and then performed an Approach Avoidance Task in which they were asked to pull or push a joystick in response to a format-feature of a series of pictures, irrespective of their contents. The pictorial stimuli used in this task included attack-related scenes and angry faces, along with neutral, positive and negative control stimuli. The results were controlled for the level of personality disorder pathology, gender, and age. The findings indicated that reactive but not proactive aggression was related to the relative behavioural tendency to approach attack-related scenes, along with positive stimuli. These findings reflect the hyper-reactivity of the approach-related reward system in reactive aggression, and further our knowledge into the distinct correlates and precursors of reactive and proactive aggression. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  11. Altered interaction with environmental reinforcers in major depressive disorder: Relationship to anhedonia.

    PubMed

    Szczepanik, Joanna E; Furey, Maura L; Nugent, Allison C; Henter, Ioline D; Zarate, Carlos A; Lejuez, Carl W

    2017-10-01

    Anhedonia-defined as loss of interest or pleasure-is one of two core symptoms of major depressive disorder (MDD). Anhedonia may involve decreased enjoyment of potentially rewarding activities and decreased motivation to engage in such activities. Increased engagement with reinforcers-activities with the potential to be positive experiences-is a frequent target of cognitive-behavioral therapies. Nevertheless, how environmental reinforcers are perceived, and how decisions to approach or avoid them are made by individuals with MDD, is largely unknown. We developed an experimental Behavioral Approach Motivation Paradigm to study how activities are evaluated and approached in MDD. Twenty-one MDD participants and 23 healthy controls performed an experimental task that rated activity words for their hedonic value, then engaged in an approach-avoidance joystick task with each individual's unique set of 'liked' and 'disliked' activity words. A negative correlation was observed between anhedonia and the number of 'liked' activities across participants. No significant difference between approach and avoidance behavior was found in direct comparisons between healthy controls and MDD participants; however, weaker avoidance and greater approach toward 'disliked' activities was found in MDD participants. This suggests negative bias in selecting environmental opportunities, potentially further compromising access to hedonic experiences in MDD. Copyright © 2017. Published by Elsevier Ltd.

  12. Training wheelchair navigation in immersive virtual environments for patients with spinal cord injury - end-user input to design an effective system.

    PubMed

    Nunnerley, Joanne; Gupta, Swati; Snell, Deborah; King, Marcus

    2017-05-01

    A user-centred design was used to develop and test the feasibility of an immersive 3D virtual reality wheelchair training tool for people with spinal cord injury (SCI). A Wheelchair Training System was designed and modelled using the Oculus Rift headset and a Dynamic Control wheelchair joystick. The system was tested by clinicians and expert wheelchair users with SCI. Data from focus groups and individual interviews were analysed using a general inductive approach to thematic analysis. Four themes emerged: Realistic System, which described the advantages of a realistic virtual environment; a Wheelchair Training System, which described participants' thoughts on the wheelchair training applications; Overcoming Resistance to Technology, the obstacles to introducing technology within the clinical setting; and Working outside the Rehabilitation Bubble which described the protective hospital environment. The Oculus Rift Wheelchair Training System has the potential to provide a virtual rehabilitation setting which could allow wheelchair users to learn valuable community wheelchair use in a safe environment. Nausea appears to be a side effect of the system, which will need to be resolved before this can be a viable clinical tool. Implications for Rehabilitation Immersive virtual reality shows promising benefit for wheelchair training in a rehabilitation setting. Early engagement with consumers can improve product development.

  13. An unmanned ground vehicle for landmine remediation

    NASA Astrophysics Data System (ADS)

    Wasson, Steven R.; Guilberto, Jose; Ogg, Wade; Wedeward, Kevin; Bruder, Stephen; El-Osery, Aly

    2004-09-01

    Anti-tank (AT) landmines slow down and endanger military advances and present sizeable humanitarian problems. The remediation of these mines by direct human intervention is both dangerous and costly. The Intelligent Systems & Robotics Group (ISRG) at New Mexico Tech has provided a partial solution to this problem by developing an Unmanned Ground Vehicle (UGV) to remediate these mines without endangering human lives. This paper presents an overview of the design and operation of this UGV. Current results and future work are also described herein. To initiate the remediation process the UGV is given the GPS coordinates of previously detected landmines. Once the UGV autonomously navigates to an acceptable proximity of the landmine, a remote operator acquires control over a wireless network link using a joystick on a base station. Utilizing two cameras mounted on the UGV, the operator is able to accurately position the UGV directly over the landmine. The UGV houses a self-contained drill system equipped with its own processing resources, sensors, and actuators. The drill system deploys a neutralizing device over the landmine to neutralize it. One such device, developed by Science Applications International Corporation (SAIC), employs incendiary materials to melt through the container of the landmine and slowly burn the explosive material, thereby safely and remotely disabling the landmine.

  14. Development and human factors analysis of an augmented reality interface for multi-robot tele-operation and control

    NASA Astrophysics Data System (ADS)

    Lee, Sam; Lucas, Nathan P.; Ellis, R. Darin; Pandya, Abhilash

    2012-06-01

    This paper presents a seamlessly controlled human multi-robot system comprised of ground and aerial robots of semiautonomous nature for source localization tasks. The system combines augmented reality interfaces capabilities with human supervisor's ability to control multiple robots. The role of this human multi-robot interface is to allow an operator to control groups of heterogeneous robots in real time in a collaborative manner. It used advanced path planning algorithms to ensure obstacles are avoided and that the operators are free for higher-level tasks. Each robot knows the environment and obstacles and can automatically generate a collision-free path to any user-selected target. It displayed sensor information from each individual robot directly on the robot in the video view. In addition, a sensor data fused AR view is displayed which helped the users pin point source information or help the operator with the goals of the mission. The paper studies a preliminary Human Factors evaluation of this system in which several interface conditions are tested for source detection tasks. Results show that the novel Augmented Reality multi-robot control (Point-and-Go and Path Planning) reduced mission completion times compared to the traditional joystick control for target detection missions. Usability tests and operator workload analysis are also investigated.

  15. On the neural control of social emotional behavior

    PubMed Central

    Roelofs, Karin; Minelli, Alessandra; Mars, Rogier B.; van Peer, Jacobien; Toni, Ivan

    2009-01-01

    It is known that the orbitofrontal cortex (OFC) is crucially involved in emotion regulation. However, the specific role of the OFC in controlling the behavior evoked by these emotions, such as approach–avoidance (AA) responses, remains largely unexplored. We measured behavioral and neural responses (using fMRI) during the performance of a social task, a reaction time (RT) task where subjects approached or avoided visually presented emotional faces by pulling or pushing a joystick, respectively. RTs were longer for affect-incongruent responses (approach angry faces and avoid happy faces) as compared to affect-congruent responses (approach–happy; avoid–angry). Moreover, affect-incongruent responses recruited increased activity in the left lateral OFC. These behavioral and neural effects emerged only when the subjects responded explicitly to the emotional value of the faces (AA-task) and largely disappeared when subjects responded to an affectively irrelevant feature of the faces during a control (gender evaluation: GE) task. Most crucially, the size of the OFC-effect correlated positively with the size of the behavioral costs of approaching angry faces. These findings qualify the role of the lateral OFC in the voluntary control of social–motivational behavior, emphasizing the relevance of this region for selecting rule-driven stimulus–response associations, while overriding automatic (affect-congruent) stimulus–response mappings. PMID:19047074

  16. Wireless powering for a self-propelled and steerable endoscopic capsule for stomach inspection.

    PubMed

    Carta, R; Tortora, G; Thoné, J; Lenaerts, B; Valdastri, P; Menciassi, A; Dario, P; Puers, R

    2009-12-15

    This paper describes the integration of an active locomotion module in a wirelessly powered endoscopic capsule. The device is a submersible capsule optimized to operate in a fluid environment in a liquid-distended stomach. A 3D inductive link is used to supply up to 400mW to the embedded electronics and a set of 4 radio-controlled motor propellers. The design takes advantage of a ferrite-core in the receiving coil-set. This approach significantly improves the coupling with the external field source with respect to earlier work by the group. It doubles the power that can be received with a coreless coil-set under identical external conditions. The upper limit of the received power was achieved complying with the strict regulations for safe exposure of biological tissue to variable magnetic fields. The wireless transferred power was proven to be sufficient to achieve the speed of 7cm/s in any directions. An optimized locomotion strategy was defined which limits the power consumption by running only 2 motors at a time. A user interface and a joystick controller allow to fully drive the capsule in an intuitive manner. The device functionalities were successfully tested in a dry and a wet environment in a laboratory set-up.

  17. Teleoperation of an experimental mobile vehicle via a free-space optical laser line-of-sight communication link for use in nuclear power plant environments

    NASA Astrophysics Data System (ADS)

    Girach, Khalid; Bouazza-Marouf, K.; Kerr, David; Hewit, Jim

    1994-11-01

    The paper describes the investigations carried out to implement a line of sight control and communication link for a mobile robot vehicle for use in structured nuclear semi-hazardous environments. Line of sight free space optical laser communication links for remote teleoperation have important applications in hazardous environments. They have certain advantages over radio/microwave links and umbilical control such as greater protection against generation of and susceptance to electro-magnetic fields. The cable-less environment provides increased integrity and mechanical freedom to the mobile robot. However, to maintain the communication link, continuous point and tracking is required between the base station and the mobile vehicle. This paper presents a novel two ended optical tracking system utilizing the communication laser beams and photodetectors. The mobile robot is a six wheel drive vehicle with a manipulator arm which can operate in a variety of terrain. The operator obtains visual feedback information from cameras placed on the vehicle. From this information, the speed and direction of the vehicle can be controlled from a joystick panel. We describe the investigations carried out for the communication of analogue video and digital data signals over the laser link for speed and direction control.

  18. A multi-segment soft actuator for biomedical applications based on IPMCs

    NASA Astrophysics Data System (ADS)

    Zhao, Dongxu; Wang, Yanjie; Liu, Jiayu; Luo, Meng; Li, Dichen; Chen, Hualing

    2015-04-01

    With rapid progress of biomedical devices towards miniaturization, flexibility, multifunction and low cost, the restrictions of traditional mechanical structures become particularly apparent, while soft materials become research focus in broad fields. As one of the most attractive soft materials, Ionic Polymer-Metal Composite (IPMC) is widely used as artificial muscles and actuators, with the advantages of low driving-voltage, high efficiency of electromechanical transduction and functional stabilization. In this paper, a new intuitive control method was presented to achieve the omnidirectional bending movements and was applied on a representative actuation structure of a multi-degree-offreedom soft actuator composed of two segments bar-shaped IPMC with a square cross section. Firstly, the bar-shaped IPMCs were fabricated by the solution casting method, reducing plating, autocatalytic plating method and cut into shapes successively. The connectors of the multi-segment IPMC actuator were fabricated by 3D printing. Then, a new control method was introduced to realize the intuitive mapping relationship between the actuator and the joystick manipulator. The control circuit was designed and tested. Finally, the multi-degree-of-freedom actuator of 2 segments bar-shaped IPMCs was implemented and omnidirectional bending movements were achieved, which could be a promising actuator for biomedical applications, such as endoscope, catheterism, laparoscopy and the surgical resection of tumors.

  19. Altered interaction with environmental reinforcers in major depressive disorder: Relationship to anhedonia

    PubMed Central

    Szczepanik, Joanna E.; Furey, Maura L.; Nugent, Allison C.; Henter, Ioline D.; Zarate, Carlos A.; Lejuez, Carl W.

    2017-01-01

    Anhedonia—defined as loss of interest or pleasure—is one of two core symptoms of major depressive disorder (MDD). Anhedonia may involve decreased enjoyment of potentially rewarding activities and decreased motivation to engage in such activities. Increased engagement with reinforcers—activities with the potential to be positive experiences—is a frequent target of cognitive-behavioral therapies. Nevertheless, how environmental reinforcers are perceived, and how decisions to approach or avoid them are made by individuals with MDD, is largely unknown. We developed an experimental Behavioral Approach Motivation Paradigm to study how activities are evaluated and approached in MDD. Twenty-one MDD participants and 23 healthy controls performed an experimental task that rated activity words for their hedonic value, then engaged in an approach-avoidance joystick task with each individual’s unique set of ‘liked’ and ‘disliked’ activity words. A negative correlation was observed between anhedonia and the number of ‘liked’ activities across participants. No significant difference between approach and avoidance behavior was found in direct comparisons between healthy controls and MDD participants; however, weaker avoidance and greater approach toward ‘disliked’ activities was found in MDD participants. This suggests negative bias in selecting environmental opportunities, potentially further compromising access to hedonic experiences in MDD. PMID:28806614

  20. Virtual reality-based navigation task to reveal obstacle avoidance performance in individuals with visuospatial neglect.

    PubMed

    Aravind, Gayatri; Darekar, Anuja; Fung, Joyce; Lamontagne, Anouk

    2015-03-01

    Persons with post-stroke visuospatial neglect (VSN) often collide with moving obstacles while walking. It is not well understood whether the collisions occur as a result of attentional-perceptual deficits caused by VSN or due to post-stroke locomotor deficits. We assessed individuals with VSN on a seated, joystick-driven obstacle avoidance task, thus eliminating the influence of locomotion. Twelve participants with VSN were tested on obstacle detection and obstacle avoidance tasks in a virtual environment that included three obstacles approaching head-on or 30 (°) contralesionally/ipsilesionally. Our results indicate that in the detection task, the contralesional and head-on obstacles were detected at closer proximities compared to the ipsilesional obstacle. For the avoidance task collisions were observed only for the contralesional and head-on obstacle approaches. For the contralesional obstacle approach, participants initiated their avoidance strategies at smaller distances from the obstacle and maintained smaller minimum distances from the obstacles. The distance at detection showed a negative association with the distance at the onset of avoidance strategy for all three obstacle approaches. We conclusion the observation of collisions with contralesional and head-on obstacles, in the absence of locomotor burden, provides evidence that attentional-perceptual deficits due to VSN, independent of post-stroke locomotor deficits, alter obstacle avoidance abilities.

  1. Multi-step routes of capuchin monkeys in a laser pointer traveling salesman task.

    PubMed

    Howard, Allison M; Fragaszy, Dorothy M

    2014-09-01

    Prior studies have claimed that nonhuman primates plan their routes multiple steps in advance. However, a recent reexamination of multi-step route planning in nonhuman primates indicated that there is no evidence for planning more than one step ahead. We tested multi-step route planning in capuchin monkeys using a pointing device to "travel" to distal targets while stationary. This device enabled us to determine whether capuchins distinguish the spatial relationship between goals and themselves and spatial relationships between goals and the laser dot, allocentrically. In Experiment 1, two subjects were presented with identical food items in Near-Far (one item nearer to subject) and Equidistant (both items equidistant from subject) conditions with a laser dot visible between the items. Subjects moved the laser dot to the items using a joystick. In the Near-Far condition, one subject demonstrated a bias for items closest to self but the other subject chose efficiently. In the second experiment, subjects retrieved three food items in similar Near-Far and Equidistant arrangements. Both subjects preferred food items nearest the laser dot and showed no evidence of multi-step route planning. We conclude that these capuchins do not make choices on the basis of multi-step look ahead strategies. © 2014 Wiley Periodicals, Inc.

  2. Natural user interface as a supplement of the holographic Raman tweezers

    NASA Astrophysics Data System (ADS)

    Tomori, Zoltan; Kanka, Jan; Kesa, Peter; Jakl, Petr; Sery, Mojmir; Bernatova, Silvie; Antalik, Marian; Zemánek, Pavel

    2014-09-01

    Holographic Raman tweezers (HRT) manipulates with microobjects by controlling the positions of multiple optical traps via the mouse or joystick. Several attempts have appeared recently to exploit touch tablets, 2D cameras or Kinect game console instead. We proposed a multimodal "Natural User Interface" (NUI) approach integrating hands tracking, gestures recognition, eye tracking and speech recognition. For this purpose we exploited "Leap Motion" and "MyGaze" low-cost sensors and a simple speech recognition program "Tazti". We developed own NUI software which processes signals from the sensors and sends the control commands to HRT which subsequently controls the positions of trapping beams, micropositioning stage and the acquisition system of Raman spectra. System allows various modes of operation proper for specific tasks. Virtual tools (called "pin" and "tweezers") serving for the manipulation with particles are displayed on the transparent "overlay" window above the live camera image. Eye tracker identifies the position of the observed particle and uses it for the autofocus. Laser trap manipulation navigated by the dominant hand can be combined with the gestures recognition of the secondary hand. Speech commands recognition is useful if both hands are busy. Proposed methods make manual control of HRT more efficient and they are also a good platform for its future semi-automated and fully automated work.

  3. A simple integrative method for presenting head-contingent motion parallax and disparity cues on intel x86 processor-based machines.

    PubMed

    Szatmary, J; Hadani, I; Julesz, B

    1997-01-01

    Rogers and Graham (1979) developed a system to show that head-movement-contingent motion parallax produces monocular depth perception in random dot patterns. Their display system comprised an oscilloscope driven by function generators or a special graphics board that triggered the X and Y deflection of the raster scan signal. Replication of this system required costly hardware that is no longer on the market. In this paper the Rogers-Graham method is reproduced with an Intel processor based IBM PC compatible machine with no additional hardware cost. An adapted joystick sampled through the standard game-port can serve as a provisional head-movement sensor. Monitor resolution for displaying motion is effectively enhanced 16 times by the use of anti-aliasing, enabling the display of thousands of random dots in real-time with a refresh rate of 60 Hz or above. A color monitor enables the use of the anaglyph method, thus combining stereoscopic and monocular parallax on a single display without the loss of speed. The power of this system is demonstrated by a psychophysical measurement in which subjects nulled head-movement-contingent illusory parallax, evoked by a static stereogram, with real parallax. The amount of real parallax required to null the illusory stereoscopic parallax monotonically increased with disparity.

  4. In action or inaction? Social approach-avoidance tendencies in major depression.

    PubMed

    Radke, Sina; Güths, Franziska; André, Julia A; Müller, Bernhard W; de Bruijn, Ellen R A

    2014-11-30

    In depression, approach deficits often impair everyday social functioning, but empirical findings on performance-based measurements of approach-avoidance behavior remain conflicting. To investigate action tendencies in patients with depression, the current study used an explicit version of the Approach-Avoidance Task (AAT). In this task, participants responded to emotional faces by either pulling a joystick toward (approach) or pushing it away from themselves (avoid). Reaction times to happy and angry expressions with direct and averted gaze were assessed in 30 patients with major depressive disorder and 20 matched healthy controls. In contrast to healthy individuals, depressed patients did not show approach-avoidance tendencies, i.e., there was no dominant behavioral tendency and they reacted to happy and angry expressions likewise. These results indicate that behavioral adjustments to different emotional expressions, gaze directions or motivational demands were lacking in depression. Crucially, this distinguishes depressed patients not only from healthy individuals, but also from other clinical populations that demonstrate aberrant approach-avoidance tendencies, e.g., patients with social anxiety or psychopathy. As responding flexibly to different social signals is integral to social interactions, the absence of any social motivational tendencies seems maladaptive, but may also provide opportunities for modifying action tendencies in a therapeutic context. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

  5. User Friendly Real Time Display

    NASA Astrophysics Data System (ADS)

    McCarthy, Denise M.; McCracken, Bill

    1989-02-01

    Real-time viewing of high resolution infrared line scan reconnaissance imagery is greatly facilitated using Honeywell's Real Time Display in conjunction with a D-500 Infrared Reconnaissance System. The Real-Time Display (RTD) provides the capability of on-board review of high resolution infrared imagery using the wide infrared dynamic range of the D-500 infrared receiver to maximum advantage. The scan converter accepts, processes, and displays imagery from four channels of the IR Receiver after formatting by a multiplexer. The scan converter interfaces with a standard RS-170 video monitor. Detailed review and on-board analysis of infrared reconnaissance imagery stored on a videotape is easily accomplished using the many user-friendly features of the RTD. Using a convenient joystick controller, on-screen mode menus, and a moveable cursor, the operator can examine scenes of interest at four different display magnifications using a four step bidirectional zoom. Imagery areas of interest are first noted using the scrolling wide field display mode at 8x reduced display resolution. On noting an area of interest, the imagery can be marked on the tape record for future recovery and a freeze frame mode can be initiated. The operator can then move the cursor to the area of interest and zoom to higher display magnification for 4x, 2x, and lx display resolutions so that the full 4096 x 4096 pixel infrared frame can be matched to the 512 x 512 pixel display frame. At 8x wide field display magnification the full line scanner field of view is displayed at 8x reduced resolution. There are two selectable modes of obtaining this reduced resolution. The operator can use the default method, which averages the signal from an 8 x 8 pixel group, or it is also possible to select the peak signal of the 8 x 8 pixel block to represent the entire block on the display. In this alternate peak-signal display the wide field can be effectively scanned for hot objects which are more likely to be candidate targets. The intermediate 4x and 2x zoom steps are very useful in maintaining operator orientation in examining target clusters and industrial complexes. The four operating modes of the RTD are described and their use to the operator on a typical mission is outlined. Some installation details are given. The RTD as part of a complete D-500 Infrared Linescan Reconnaissance System is now being installed on a Beech 1900 Environmental Control Aircraft to monitor pollution in very sensitive and commercially important marine ecologies. Its application on military reconnaissance missions will allow the normal review of recorded videotape imagery at a ground station immediately after return of the aircraft to base. The areas of highest interest will have been previously marked during the airborne real-time review by the operator. The RTD packages into only two Line Replaceable Units (LRUs), a Scan Converter, and a Control Unit which includes a joystick hand controller. The CRT display is assumed to be part of the aircraft.

  6. Dynamics and Embedded Internet of Things Input Shaping Control for Overhead Cranes Transporting Multibody Payloads.

    PubMed

    Peláez, Gerardo; Vaugan, Joshua; Izquierdo, Pablo; Rubio, Higinio; García-Prada, Juan Carlos

    2018-06-04

    Input shaping is an Optimal Control feedforward strategy whose ability to define how and when a flexible dynamical system defined by Ordinary Differential Equations (ODEs) and computer controlled would move into its operative space, without command induced unwanted dynamics, has been exhaustively demonstrated. This work examines the issue of Embedded Internet of Things (IoT) Input Shaping with regard to real time control of multibody oscillatory systems whose dynamics are better described by differential algebraic equations (DAEs). An overhead crane hanging a double link multibody payload has been appointed as a benchmark case; it is a multibody, multimode system. This might be worst scenario to implement Input Shaping. The reasons can be found in the wide array of constraints that arise. Firstly, the reliability of the multibody model was tested on a Functional Mock-Up Interface (FMI) with the two link payload suspended from the trolley by comparing the experimental video tapping signals in time domain faced with the signals extracted from the multibody model. The FFTs of the simulated and the experimental signal contain the same frequency harmonics only with somewhat different power due to the real world light damping in the joints. The application of this approach may be extended to other cases i.e., the usefulness of mobile hydraulic cranes is limited because the payload is supported by an overhead cable under tension that allows oscillation to occur during crane motion. If the payload size is not negligible small when compared with the cable length may introduce an additional oscillatory mode that creates a multibody double pendulum. To give the insight into the double pendulum dynamics by Lagrangian methods two slender rods as payloads are analyzed dealing with the overhead crane and a composite revolute-revolute joint is proposed to model the cable of the hydraulic crane, both assumptions facilitates an affordable analysis. This allows developing a general study of this type of multibody payloads dynamics including its normal modes, modes ratios plus ranges of frequencies expected. Input Shapers were calculated for those multimodes of vibration by convolving Specified Insensitivity (SI) shapers for each mode plus a novel Direct SI-SI shaper well suited to reduce the computational requirements, i.e., the number of the shaper taps, to carry out the convolution sum in real time by the IoT device based on a single microcontroller working as the command generator. Several comparisons are presented for the shaped and unshaped responses using both the multibody model, the experimental FMI set-up and finally a real world hydraulic crane under slewing motion commanded by an analog Joystick connected by two RF modules 802.15.4 to the IoT device that carry out the convolution sum in real time. Input Shaping improves the performances for all the cases.

  7. Gaze direction differentially affects avoidance tendencies to happy and angry faces in socially anxious individuals.

    PubMed

    Roelofs, Karin; Putman, Peter; Schouten, Sonja; Lange, Wolf-Gero; Volman, Inge; Rinck, Mike

    2010-04-01

    Increasing evidence indicates that eye gaze direction affects the processing of emotional faces in anxious individuals. However, the effects of eye gaze direction on the behavioral responses elicited by emotional faces, such as avoidance behavior, remain largely unexplored. We administered an Approach-Avoidance Task (AAT) in high (HSA) and low socially anxious (LSA) individuals. All participants responded to photographs of angry, happy and neutral faces (presented with direct and averted gaze), by either pushing a joystick away from them (avoidance) or pulling it towards them (approach). Compared to LSA, HSA were faster in avoiding than approaching angry faces. Most crucially, this avoidance tendency was only present when the perceived anger was directed towards the subject (direct gaze) and not when the gaze of the face-stimulus was averted. In contrast, HSA individuals tended to avoid happy faces irrespectively of gaze direction. Neutral faces elicited no approach-avoidance tendencies. Thus avoidance of angry faces in social anxiety as measured by AA-tasks reflects avoidance of subject-directed anger and not of negative stimuli in general. In addition, although both anger and joy are considered to reflect approach-related emotions, gaze direction did not affect HSA's avoidance of happy faces, suggesting differential mechanisms affecting responses to happy and angry faces in social anxiety. 2009 Elsevier Ltd. All rights reserved.

  8. ARENA - A Collaborative Immersive Environment for Virtual Fieldwork

    NASA Astrophysics Data System (ADS)

    Kwasnitschka, T.

    2012-12-01

    Whenever a geoscientific study area is not readily accessible, as is the case on the deep seafloor, it is difficult to apply traditional but effective methods of fieldwork, which often require physical presence of the observer. The Artificial Research Environment for Networked Analysis (ARENA), developed at GEOMAR | Helmholtz Centre for Ocean Research Kiel within the Cluster of Excellence "The Future Ocean", provides a backend solution to robotic research on the seafloor by means of an immersive simulation environment for marine research: A hemispherical screen of 6m diameter covering the entire lower hemisphere surrounds a group of up to four researchers at once. A variety of open source (e.g. Microsoft Research World Wide Telescope) and commercial software platforms allow the interaction with e.g. in-situ recorded video, vector maps, terrain, textured geometry, point cloud and volumetric data in four dimensions. Data can be put into a holistic, georeferenced context and viewed on scales stretching from centimeters to global. Several input devices from joysticks to gestures and vocalized commands allow interaction with the simulation, depending on individual preference. Annotations added to the dataset during the simulation session catalyze the following quantitative evaluation. Both the special simulator design, making data perception a group experience, and the ability to connect remote instances or scaled down versions of ARENA over the Internet are significant advantages over established immersive simulation environments.

  9. On the relationship between human search strategies, conspicuity, and search performance

    NASA Astrophysics Data System (ADS)

    Hogervorst, Maarten A.; Bijl, Piet; Toet, Alexander

    2005-05-01

    We determined the relationship between search performance with a limited field of view (FOV) and several scanning- and scene parameters in human observer experiments. The observers (38 trained army scouts) searched through a large search sector for a target (a camouflaged person) on a heath. From trial to trial the target appeared at a different location. With a joystick the observers scanned through a panoramic image (displayed on a PC-monitor) while the scan path was registered. Four conditions were run differing in sensor type (visual or thermal infrared) and window size (large or small). In conditions with a small window size the zoom option could be used. Detection performance was highly dependent on zoom factor and deteriorated when scan speed increased beyond a threshold value. Moreover, the distribution of scan speeds scales with the threshold speed. This indicates that the observers are aware of their limitations and choose a (near) optimal search strategy. We found no correlation between the fraction of detected targets and overall search time for the individual observers, indicating that both are independent measures of individual search performance. Search performance (fraction detected, total search time, time in view for detection) was found to be strongly related to target conspicuity. Moreover, we found the same relationship between search performance and conspicuity for visual and thermal targets. This indicates that search performance can be predicted directly by conspicuity regardless of the sensor type.

  10. A Virtual Joy-Stick Study of Emotional Responses and Social Motivation in Children with Autism Spectrum Disorder

    PubMed Central

    Kim, Kwanguk; Rosenthal, M. Zachary; Gwaltney, Mary; Jarrold, William; Hatt, Naomi; McIntyre, Nancy; Swain, Lindsay; Solomon, Marjorie

    2017-01-01

    A new virtual reality task was employed which uses preference for interpersonal distance to social stimuli to examine social motivation and emotion perception in children with Autism Spectrum Disorders. Nineteen high function children with higher functioning Autism Spectrum Disorder (HFASD) and 23 age, gender, and IQ matched children with typical development (TD) used a joy stick to position themselves closer or further from virtual avatars while attempting to identify six emotions expressed by the avatars, happiness, fear, anger, disgust, sadness, and surprise that were expressed at different levels of intensity. The results indicated that children with HFASD displayed significantly less approach behavior to the positive happy expression than did children with TD, who displayed increases in approach behavior to higher intensities of happy expressions. Alternatively, all groups tended to withdraw from negative emotions to the same extent and there were no diagnostic group differences in accuracy of recognition of any of the six emotions. This pattern of results is consistent with theory that suggests that some children with HFASD display atypical social-approach motivation, or sensitivity to the positive reward value of positive social–emotional events. Conversely, there was little evidence that a tendency to withdraw from social–emotional stimuli, or a failure to process social emotional stimuli, was a component of social behavior task performance in this sample of children with HFASD. PMID:24435405

  11. A Virtual Joy-Stick Study of Emotional Responses and Social Motivation in Children with Autism Spectrum Disorder.

    PubMed

    Kim, Kwanguk; Rosenthal, M Zachary; Gwaltney, Mary; Jarrold, William; Hatt, Naomi; McIntyre, Nancy; Swain, Lindsay; Solomon, Marjorie; Mundy, Peter

    2015-12-01

    A new virtual reality task was employed which uses preference for interpersonal distance to social stimuli to examine social motivation and emotion perception in children with Autism Spectrum Disorders. Nineteen high function children with higher functioning Autism Spectrum Disorder (HFASD) and 23 age, gender, and IQ matched children with typical development (TD) used a joy stick to position themselves closer or further from virtual avatars while attempting to identify six emotions expressed by the avatars, happiness, fear, anger, disgust, sadness, and surprise that were expressed at different levels of intensity. The results indicated that children with HFASD displayed significantly less approach behavior to the positive happy expression than did children with TD, who displayed increases in approach behavior to higher intensities of happy expressions. Alternatively, all groups tended to withdraw from negative emotions to the same extent and there were no diagnostic group differences in accuracy of recognition of any of the six emotions. This pattern of results is consistent with theory that suggests that some children with HFASD display atypical social-approach motivation, or sensitivity to the positive reward value of positive social-emotional events. Conversely, there was little evidence that a tendency to withdraw from social-emotional stimuli, or a failure to process social emotional stimuli, was a component of social behavior task performance in this sample of children with HFASD.

  12. Graph analysis of functional brain networks for cognitive control of action in traumatic brain injury.

    PubMed

    Caeyenberghs, Karen; Leemans, Alexander; Heitger, Marcus H; Leunissen, Inge; Dhollander, Thijs; Sunaert, Stefan; Dupont, Patrick; Swinnen, Stephan P

    2012-04-01

    Patients with traumatic brain injury show clear impairments in behavioural flexibility and inhibition that often persist beyond the time of injury, affecting independent living and psychosocial functioning. Functional magnetic resonance imaging studies have shown that patients with traumatic brain injury typically show increased and more broadly dispersed frontal and parietal activity during performance of cognitive control tasks. We constructed binary and weighted functional networks and calculated their topological properties using a graph theoretical approach. Twenty-three adults with traumatic brain injury and 26 age-matched controls were instructed to switch between coordination modes while making spatially and temporally coupled circular motions with joysticks during event-related functional magnetic resonance imaging. Results demonstrated that switching performance was significantly lower in patients with traumatic brain injury compared with control subjects. Furthermore, although brain networks of both groups exhibited economical small-world topology, altered functional connectivity was demonstrated in patients with traumatic brain injury. In particular, compared with controls, patients with traumatic brain injury showed increased connectivity degree and strength, and higher values of local efficiency, suggesting adaptive mechanisms in this group. Finally, the degree of increased connectivity was significantly correlated with poorer switching task performance and more severe brain injury. We conclude that analysing the functional brain network connectivity provides new insights into understanding cognitive control changes following brain injury.

  13. Robotically assisted ureteroscopy for kidney exploration.

    PubMed

    Talari, Hadi F; Monfaredi, Reza; Wilson, Emmanuel; Blum, Emily; Bayne, Christopher; Peters, Craig; Zhang, Anlin; Cleary, Kevin

    2017-02-01

    Ureteroscopy is a minimally invasive procedure for diagnosis and treatment of a wide range of urinary tract pathologies. It is most commonly performed in the diagnostic work-up of hematuria and the diagnosis and treatment of upper urinary tract malignancies and calculi. Ergonomic and visualization challenges as well as radiation exposure are limitations to conventional ureteroscopy. For example, for diagnostic tumor inspection, the urologist has to maneuver the ureteroscope through each of the 6 to 12 calyces in the kidney under fluoroscopy to ensure complete surveillance. Therefore, we have been developing a robotic system to "power drive" a flexible fiber-optic ureteroscope with 3D tip tracking and pre-operative image overlay. Our goal is to provide the urologist precise control of the ureteroscope tip with less radiation exposure. Our prototype system allows control of the three degrees of freedom of the ureteroscope via brushless motors and a joystick interface. The robot provides a steady platform for controlling the ureteroscope. Furthermore, the robot design facilitates a quick "snap-in" of the ureteroscope, thus allowing the ureteroscope to be mounted midway through the procedure. We have completed the mechanical system and the controlling software and begun evaluation using a kidney phantom. We put MRI-compatible fiducials on the phantom and obtained MR images. We registered these images with the robot using an electromagnetic tracking system and paired-point registration. The system is described and initial evaluation results are given in this paper.

  14. VIRTUAL FRAME BUFFER INTERFACE

    NASA Technical Reports Server (NTRS)

    Wolfe, T. L.

    1994-01-01

    Large image processing systems use multiple frame buffers with differing architectures and vendor supplied user interfaces. This variety of architectures and interfaces creates software development, maintenance, and portability problems for application programs. The Virtual Frame Buffer Interface program makes all frame buffers appear as a generic frame buffer with a specified set of characteristics, allowing programmers to write code which will run unmodified on all supported hardware. The Virtual Frame Buffer Interface converts generic commands to actual device commands. The virtual frame buffer consists of a definition of capabilities and FORTRAN subroutines that are called by application programs. The virtual frame buffer routines may be treated as subroutines, logical functions, or integer functions by the application program. Routines are included that allocate and manage hardware resources such as frame buffers, monitors, video switches, trackballs, tablets and joysticks; access image memory planes; and perform alphanumeric font or text generation. The subroutines for the various "real" frame buffers are in separate VAX/VMS shared libraries allowing modification, correction or enhancement of the virtual interface without affecting application programs. The Virtual Frame Buffer Interface program was developed in FORTRAN 77 for a DEC VAX 11/780 or a DEC VAX 11/750 under VMS 4.X. It supports ADAGE IK3000, DEANZA IP8500, Low Resolution RAMTEK 9460, and High Resolution RAMTEK 9460 Frame Buffers. It has a central memory requirement of approximately 150K. This program was developed in 1985.

  15. Low-cost real-time 3D PC distributed-interactive-simulation (DIS) application for C4I

    NASA Astrophysics Data System (ADS)

    Gonthier, David L.; Veron, Harry

    1998-04-01

    A 3D Distributed Interactive Simulation (DIS) application was developed and demonstrated in a PC environment. The application is capable of running in the stealth mode or as a player which includes battlefield simulations, such as ModSAF. PCs can be clustered together, but not necessarily collocated, to run a simulation or training exercise on their own. A 3D perspective view of the battlefield is displayed that includes terrain, trees, buildings and other objects supported by the DIS application. Screen update rates of 15 to 20 frames per second have been achieved with fully lit and textured scenes thus providing high quality and fast graphics. A complete PC system can be configured for under $2,500. The software runs under Windows95 and WindowsNT. It is written in C++ and uses a commercial API called RenderWare for 3D rendering. The software uses Microsoft Foundation classes and Microsoft DirectPlay for joystick input. The RenderWare libraries enhance the performance through optimization for MMX and the Pentium Pro processor. The RenderWare and the Righteous 3D graphics board from Orchid Technologies with an advertised rendering rate of up to 2 million texture mapped triangles per second. A low-cost PC DIS simulator that can partake in a real-time collaborative simulation with other platforms is thus achieved.

  16. Pain in context: Cues predicting a reward decrease fear of movement related pain and avoidance behavior.

    PubMed

    Claes, Nathalie; Vlaeyen, Johan W S; Crombez, Geert

    2016-09-01

    Previous research shows that goal-directed behavior might be modulated by cues that predict (dis)similar outcomes. However, the literature investigating this modulation with pain outcomes is scarce. Therefore, this experiment investigated whether environmental cues predicting pain or reward modulate defensive pain responding. Forty-eight healthy participants completed a joystick movement task with two different movement orientations. Performing one movement was associated with a painful stimulus, whereas performance of another movement was associated with reward, i.e. lottery tickets. In a subsequent task, participants learned to associate three different cues withpain, reward, or neither of the two. Next, these cues were integrated in the movement task. This study demonstrates that in general, aversive cues enhance and appetitive cues reduce pain-related fear. Furthermore, we found that incongruence between the outcomes predicted by the movement and the cue results in more oscillatory behavior, i.e., participants were more willing to perform a painful movement when a cue predicting reward was simultaneously presented, and vice versa. Similarly, when given a choice, participants preferred to perform the reward movement, unless there was an incongruence between the outcomes predicted by the movements and cues. Taken together, these results provide experimental evidence that environmental cues are capable of modulating pain-related fear and avoidance behavior. Copyright © 2016 Elsevier Ltd. All rights reserved.

  17. Interface for Physics Simulation Engines

    NASA Technical Reports Server (NTRS)

    Damer, Bruce

    2007-01-01

    DSS-Prototyper is an open-source, realtime 3D virtual environment software that supports design simulation for the new Vision for Space Exploration (VSE). This is a simulation of NASA's proposed Robotic Lunar Exploration Program, second mission (RLEP2). It simulates the Lunar Surface Access Module (LSAM), which is designed to carry up to four astronauts to the lunar surface for durations of a week or longer. This simulation shows the virtual vehicle making approaches and landings on a variety of lunar terrains. The physics of the descent engine thrust vector, production of dust, and the dynamics of the suspension are all modeled in this set of simulations. The RLEP2 simulations are drivable (by keyboard or joystick) virtual rovers with controls for speed and motor torque, and can be articulated into higher or lower centers of gravity (depending on driving hazards) to enable drill placement. Gravity also can be set to lunar, terrestrial, or zero-g. This software has been used to support NASA's Marshall Space Flight Center in simulations of proposed vehicles for robotically exploring the lunar surface for water ice, and could be used to model all other aspects of the VSE from the Ares launch vehicles and Crew Exploration Vehicle (CEV) to the International Space Station (ISS). This simulator may be installed and operated on any Windows PC with an installed 3D graphics card.

  18. An experimental test of the role of control in spider fear.

    PubMed

    Healey, Andrew; Mansell, Warren; Tai, Sara

    2017-06-01

    It is well established that uncontrollable adverse experiences lead to increased distress, but the role of client control during psychological interventions such as exposure is less clear. Earlier studies reported inconsistent findings, most likely owing to variations in the way client control was manipulated, degree of exposure, the outcome variables chosen and the follow-up periods used. Importantly, studies to date had suggested to participants that approaching their fears was beneficial thereby biasing their choices and these studies had not measured change beyond the laboratory. We recruited 96 spider-fearful student participants (mean age=22; SD=5.9; Range=18-45; 86 female). The experimental design allowed full choice over their degree of exposure, and manipulated the degree of control as the extent to which their movement of a joystick influenced their virtual distance from a moving spider image. Those with high control were yoked with a low control counterpart to ensure equal amounts of exposure. Measures were elicited at baseline, post-exposure, and at follow-up. As predicted, compared to low control participants, those with high control over exposure approached closer toward a spider post-exposure and reported less spider avoidance after an average of 17days. No group differences were found in physiological or subjective distress during the task, nor in distress and dysfunction. Copyright © 2017 Elsevier Ltd. All rights reserved.

  19. An Intention-Driven Semi-autonomous Intelligent Robotic System for Drinking.

    PubMed

    Zhang, Zhijun; Huang, Yongqian; Chen, Siyuan; Qu, Jun; Pan, Xin; Yu, Tianyou; Li, Yuanqing

    2017-01-01

    In this study, an intention-driven semi-autonomous intelligent robotic (ID-SIR) system is designed and developed to assist the severely disabled patients to live independently. The system mainly consists of a non-invasive brain-machine interface (BMI) subsystem, a robot manipulator and a visual detection and localization subsystem. Different from most of the existing systems remotely controlled by joystick, head- or eye tracking, the proposed ID-SIR system directly acquires the intention from users' brain. Compared with the state-of-art system only working for a specific object in a fixed place, the designed ID-SIR system can grasp any desired object in a random place chosen by a user and deliver it to his/her mouth automatically. As one of the main advantages of the ID-SIR system, the patient is only required to send one intention command for one drinking task and the autonomous robot would finish the rest of specific controlling tasks, which greatly eases the burden on patients. Eight healthy subjects attended our experiment, which contained 10 tasks for each subject. In each task, the proposed ID-SIR system delivered the desired beverage container to the mouth of the subject and then put it back to the original position. The mean accuracy of the eight subjects was 97.5%, which demonstrated the effectiveness of the ID-SIR system.

  20. How to avoid simulation sickness in virtual environments during user displacement

    NASA Astrophysics Data System (ADS)

    Kemeny, A.; Colombet, F.; Denoual, T.

    2015-03-01

    Driving simulation (DS) and Virtual Reality (VR) share the same technologies for visualization and 3D vision and may use the same technics for head movement tracking. They experience also similar difficulties when rendering the displacements of the observer in virtual environments, especially when these displacements are carried out using driver commands, including steering wheels, joysticks and nomad devices. High values for transport delay, the time lag between the action and the corresponding rendering cues and/or visual-vestibular conflict, due to the discrepancies perceived by the human visual and vestibular systems when driving or displacing using a control device, induces the so-called simulation sickness. While the visual transport delay can be efficiently reduced using high frequency frame rate, the visual-vestibular conflict is inherent to VR, when not using motion platforms. In order to study the impact of displacements on simulation sickness, we have tested various driving scenarios in Renault's 5-sided ultra-high resolution CAVE. First results indicate that low speed displacements with longitudinal and lateral accelerations under a given perception thresholds are well accepted by a large number of users and relatively high values are only accepted by experienced users and induce VR induced symptoms and effects (VRISE) for novice users, with a worst case scenario corresponding to rotational displacements. These results will be used for optimization technics at Arts et Métiers ParisTech for motion sickness reduction in virtual environments for industrial, research, educational or gaming applications.

  1. Design and Performance Evaluation of Real-time Endovascular Interventional Surgical Robotic System with High Accuracy.

    PubMed

    Wang, Kundong; Chen, Bing; Lu, Qingsheng; Li, Hongbing; Liu, Manhua; Shen, Yu; Xu, Zhuoyan

    2018-05-15

    Endovascular interventional surgery (EIS) is performed under a high radiation environment at the sacrifice of surgeons' health. This paper introduces a novel endovascular interventional surgical robot that aims to reduce radiation to surgeons and physical stress imposed by lead aprons during fluoroscopic X-ray guided catheter intervention. The unique mechanical structure allowed the surgeon to manipulate the axial and radial motion of the catheter and guide wire. Four catheter manipulators (to manipulate the catheter and guide wire), and a control console which consists of four joysticks, several buttons and two twist switches (to control the catheter manipulators) were presented. The entire robotic system was established on a master-slave control structure through CAN (Controller Area Network) bus communication, meanwhile, the slave side of this robotic system showed highly accurate control over velocity and displacement with PID controlling method. The robotic system was tested and passed in vitro and animal experiments. Through functionality evaluation, the manipulators were able to complete interventional surgical motion both independently and cooperatively. The robotic surgery was performed successfully in an adult female pig and demonstrated the feasibility of superior mesenteric and common iliac artery stent implantation. The entire robotic system met the clinical requirements of EIS. The results show that the system has the ability to imitate the movements of surgeons and to accomplish the axial and radial motions with consistency and high-accuracy. Copyright © 2018 John Wiley & Sons, Ltd.

  2. Looking behind the score: Skill structure explains sex differences in skilled video game performance

    PubMed Central

    Boot, Walter R.; Ericsson, K. Anders

    2018-01-01

    Some have explained large sex differences in visuospatial abilities by genetic adaptations to different roles in primitive hunter-gatherer societies and the interaction of innate biological differences and environmental factors. We explored the extent to which variations in behavior and acquired skills can provide alternative accounts for sex differences in the performance of a complex spatially-demanding video game (Space Fortress). Men and women with limited video game experience were given 30 hours of training, and latent curve analyses examined the development of their ship control performance and behavior. Men had significantly better control performance than women before and after training, but differences diminished substantially over the training period. An analysis of participants’ joystick behaviors revealed that initially men and women relied on different patterns of control behaviors, but changes in these behaviors over time accounted for the reduced sex differences in performance. When we controlled for these differences in behavior, sex effects after training were no longer significant. Finally, examining the development of control performance and control behaviors of men and women categorized as initially high and low performers revealed the lower-performing women may have been controlling their ship using an approach that was very different from the men and higher-performing women. The potential problems of analyzing men and women’s spatial performance as homogenous groups are discussed, as well as how these issues may account for sex differences in skilled video game performance and perhaps other domains involving spatial abilities. PMID:29847565

  3. Simulation Exploration through Immersive Parallel Planes

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Brunhart-Lupo, Nicholas J; Bush, Brian W; Gruchalla, Kenny M

    We present a visualization-driven simulation system that tightly couples systems dynamics simulations with an immersive virtual environment to allow analysts to rapidly develop and test hypotheses in a high-dimensional parameter space. To accomplish this, we generalize the two-dimensional parallel-coordinates statistical graphic as an immersive 'parallel-planes' visualization for multivariate time series emitted by simulations running in parallel with the visualization. In contrast to traditional parallel coordinate's mapping the multivariate dimensions onto coordinate axes represented by a series of parallel lines, we map pairs of the multivariate dimensions onto a series of parallel rectangles. As in the case of parallel coordinates, eachmore » individual observation in the dataset is mapped to a polyline whose vertices coincide with its coordinate values. Regions of the rectangles can be 'brushed' to highlight and select observations of interest: a 'slider' control allows the user to filter the observations by their time coordinate. In an immersive virtual environment, users interact with the parallel planes using a joystick that can select regions on the planes, manipulate selection, and filter time. The brushing and selection actions are used to both explore existing data as well as to launch additional simulations corresponding to the visually selected portions of the input parameter space. As soon as the new simulations complete, their resulting observations are displayed in the virtual environment. This tight feedback loop between simulation and immersive analytics accelerates users' realization of insights about the simulation and its output.« less

  4. Design and Evaluation of a Stand-Up Motorized Prone Cart

    PubMed Central

    Harrow, Jeffrey J; Malassigné, Pascal; Nelson, Audrey L; Jensen, Robert P; Amato, Margaret; Palacios, Polly L

    2007-01-01

    Background/Objective: Prone carts are used for mobility by individuals with spinal cord injury in whom seated mobility (wheelchair) is contraindicated due to ischial or sacral pressure ulcers. Currently available prone carts are uncomfortable, subjecting the user to neck and shoulder strain, and make social interaction and performing activities of daily living difficult. A better design of prone carts is needed. In addition, standing devices have shown some medical benefits. The objective was to design and evaluate an improved prone cart that facilitates standing. Design: Engineering development project with user feedback through questionnaire. Users selected by convenience sampling. Methods: A marketing survey was performed of nurse managers of spinal cord injury units. Then 2 prototype carts were designed and built. These carts are able to tilt up to 45° and have a joystick-controlled motor for propulsion and other design features, including a workspace storage shelf and rearview mirrors. The carts were evaluated by both patients and caregivers at 2 Veteran's Administration hospitals. Outcome Measures: Questionnaire of subjects, both patients and caregivers, who used the cart. Findings: Both patients and caregivers liked the carts and the ability to assume a nonhorizontal body angle. The major complaint about the cart was that it seemed too long when it came to making turns. Conclusion: This prone cart design is an improvement over the standard, flat variety. However, further design changes will be necessary. This study provided valuable information that will be useful in the next-generation prone cart design project. PMID:17385270

  5. Novel Technique for Rebubbling DMEK Grafts at the Slit Lamp Using Intravenous Extension Tubing.

    PubMed

    Sáles, Christopher S; Straiko, Michael D; Terry, Mark A

    2016-04-01

    To describe a novel technique for rebubbling DMEK grafts at the slit lamp using a cannula coupled to a syringe with intravenous (IV) extension tubing. We present a retrospective case series of eyes that underwent rebubbling using a novel technique at the slit lamp. The rebubbling apparatus is assembled using a standard 43-inch IV extension tube, a 5-cc luer lock syringe, and a 27-gauge cannula. The cannula is screwed onto one end of the extension tubing, and a 5-cc syringe that has been filled with air is screwed onto the opposite end. With the patient seated at the slit lamp, the cannula is positioned in the anterior chamber by the surgeon with one hand while the other hand operates the syringe and the joystick. We performed 5 rebubbling procedures at the slit lamp using a standard syringe and cannula. Despite suboptimal ergonomics with this approach, all of these cases achieved sufficient air fills without any complications. Four rebubbling procedures were subsequently performed at the slit lamp using our novel rebubbling technique. All of these cases also attained sufficient air fills without complications, but they were noted to be much easier to perform by the surgeon. Using IV extension tubing to couple a syringe to a cannula for rebubbling DMEK grafts at the slit lamp is ergonomically superior to the conventional alternative of using a standard cannula on a syringe. The technique is also simple and inexpensive to adopt.

  6. Robotically assisted ureteroscopy for kidney exploration

    PubMed Central

    Talari, Hadi F.; Monfaredi, Reza; Wilson, Emmanuel; Blum, Emily; Bayne, Christopher; Peters, Craig; Zhang, Anlin; Cleary, Kevin

    2018-01-01

    Ureteroscopy is a minimally invasive procedure for diagnosis and treatment of a wide range of urinary tract pathologies. It is most commonly performed in the diagnostic work-up of hematuria and the diagnosis and treatment of upper urinary tract malignancies and calculi. Ergonomic and visualization challenges as well as radiation exposure are limitations to conventional ureteroscopy. For example, for diagnostic tumor inspection, the urologist has to maneuver the ureteroscope through each of the 6 to 12 calyces in the kidney under fluoroscopy to ensure complete surveillance. Therefore, we have been developing a robotic system to “power drive” a flexible fiber-optic ureteroscope with 3D tip tracking and pre-operative image overlay. Our goal is to provide the urologist precise control of the ureteroscope tip with less radiation exposure. Our prototype system allows control of the three degrees of freedom of the ureteroscope via brushless motors and a joystick interface. The robot provides a steady platform for controlling the ureteroscope. Furthermore, the robot design facilitates a quick “snap-in” of the ureteroscope, thus allowing the ureteroscope to be mounted midway through the procedure. We have completed the mechanical system and the controlling software and begun evaluation using a kidney phantom. We put MRI-compatible fiducials on the phantom and obtained MR images. We registered these images with the robot using an electromagnetic tracking system and paired-point registration. The system is described and initial evaluation results are given in this paper. PMID:29731536

  7. Surgical bedside master console for neurosurgical robotic system.

    PubMed

    Arata, Jumpei; Kenmotsu, Hajime; Takagi, Motoki; Hori, Tatsuya; Miyagi, Takahiro; Fujimoto, Hideo; Kajita, Yasukazu; Hayashi, Yuichiro; Chinzei, Kiyoyuki; Hashizume, Makoto

    2013-01-01

    We are currently developing a neurosurgical robotic system that facilitates access to residual tumors and improves brain tumor removal surgical outcomes. The system combines conventional and robotic surgery allowing for a quick conversion between the procedures. This concept requires a new master console that can be positioned at the surgical bedside and be sterilized. The master console was developed using new technologies, such as a parallel mechanism and pneumatic sensors. The parallel mechanism is a purely passive 5-DOF (degrees of freedom) joystick based on the author's haptic research. The parallel mechanism enables motion input of conventional brain tumor removal surgery with a compact, intuitive interface that can be used in a conventional surgical environment. In addition, the pneumatic sensors implemented on the mechanism provide an intuitive interface and electrically isolate the tool parts from the mechanism so they can be easily sterilized. The 5-DOF parallel mechanism is compact (17 cm width, 19cm depth, and 15cm height), provides a 505,050 mm and 90° workspace and is highly backdrivable (0.27N of resistance force representing the surgical motion). The evaluation tests revealed that the pneumatic sensors can properly measure the suction strength, grasping force, and hand contact. In addition, an installability test showed that the master console can be used in a conventional surgical environment. The proposed master console design was shown to be feasible for operative neurosurgery based on comprehensive testing. This master console is currently being tested for master-slave control with a surgical robotic system.

  8. The effect of withdrawal of visual presentation of errors upon the frequency spectrum of tremor in a manual task

    PubMed Central

    Sutton, G. G.; Sykes, K.

    1967-01-01

    1. When a subject attempts to exert a steady pressure on a joystick he makes small unavoidable errors which, irrespective of their origin or frequency, may be called tremor. 2. Frequency analysis shows that low frequencies always contribute much more to the total error than high frequencies. If the subject is not allowed to check his performance visually, but has to rely on sensations of pressure in the finger tips, etc., the error power spectrum plotted on logarithmic co-ordinates approximates to a straight line falling at 6 db/octave from 0·4 to 9 c/s. In other words the amplitude of the tremor component at each frequency is inversely proportional to frequency. 3. When the subject is given a visual indication of his errors on an oscilloscope the shape of the tremor spectrum alters. The most striking change is the appearance of a tremor peak at about 9 c/s, but there is also a significant increase of error in the range 1-4 c/s. The extent of these changes varies from subject to subject. 4. If the 9 c/s peak represents oscillation of a muscle length-servo it would appear that greater use is made of this servo when positional information is available from the eyes than when proprioceptive impulses from the limbs have to be relied on. ImagesFig. 2 PMID:6048997

  9. Effect of Achilles tendon vibration on postural orientation.

    PubMed

    Ceyte, Hadrien; Cian, Corinne; Zory, Raphael; Barraud, Pierre-Alain; Roux, Alain; Guerraz, Michel

    2007-04-06

    Vibration applied to the Achilles tendon is well known to induce in freely standing subjects a backward body displacement and in restrained subjects an illusory forward body tilt. The purpose of the present experiment was to evaluate the effect of Achilles tendon vibration (90Hz) on postural orientation in subjects free of equilibrium constraints. Subjects (n=12) were strapped on a backboard that could be rotated in the antero-posterior direction with the axis of rotation at the level of the ankles. They stood on a rigid horizontal floor with the soles of their feet parallel to the ground. They were initially positioned 7 degrees backward or forward or vertical and were required to adjust their body (the backboard) to the vertical orientation via a joystick. Firstly, results showed that in response to Achilles tendon vibration, subjects adjusted their body backward compared to the condition without vibration. This backward body adjustment likely cancel the appearance of an illusory forward body tilt. It was also observed that the vibratory stimulus applied to the Achilles tendon elicited in restrained standing subjects an increased EMG activity in both the gastrocnemius lateralis and the soleus muscles. Secondly, this vibration effect was more pronounced when passive displacement during the adjustment phase was congruent with the simulated elongation of calf muscles. These results indicated that the perception of body orientation is coherent with the postural response classically observed in freely standing subjects although the relationship between these two responses remains to be elucidated.

  10. Evaluation of navigation interfaces in virtual environments

    NASA Astrophysics Data System (ADS)

    Mestre, Daniel R.

    2014-02-01

    When users are immersed in cave-like virtual reality systems, navigational interfaces have to be used when the size of the virtual environment becomes larger than the physical extent of the cave floor. However, using navigation interfaces, physically static users experience self-motion (visually-induced vection). As a consequence, sensorial incoherence between vision (indicating self-motion) and other proprioceptive inputs (indicating immobility) can make them feel dizzy and disoriented. We tested, in two experimental studies, different locomotion interfaces. The objective was twofold: testing spatial learning and cybersickness. In a first experiment, using first-person navigation with a flystick ®, we tested the effect of sensorial aids, a spatialized sound or guiding arrows on the ground, attracting the user toward the goal of the navigation task. Results revealed that sensorial aids tended to impact negatively spatial learning. Moreover, subjects reported significant levels of cybersickness. In a second experiment, we tested whether such negative effects could be due to poorly controlled rotational motion during simulated self-motion. Subjects used a gamepad, in which rotational and translational displacements were independently controlled by two joysticks. Furthermore, we tested first- versus third-person navigation. No significant difference was observed between these two conditions. Overall, cybersickness tended to be lower, as compared to experiment 1, but the difference was not significant. Future research should evaluate further the hypothesis of the role of passively perceived optical flow in cybersickness, but manipulating the virtual environment'sperrot structure. It also seems that video-gaming experience might be involved in the user's sensitivity to cybersickness.

  11. Looking behind the score: Skill structure explains sex differences in skilled video game performance.

    PubMed

    Harwell, Kyle W; Boot, Walter R; Ericsson, K Anders

    2018-01-01

    Some have explained large sex differences in visuospatial abilities by genetic adaptations to different roles in primitive hunter-gatherer societies and the interaction of innate biological differences and environmental factors. We explored the extent to which variations in behavior and acquired skills can provide alternative accounts for sex differences in the performance of a complex spatially-demanding video game (Space Fortress). Men and women with limited video game experience were given 30 hours of training, and latent curve analyses examined the development of their ship control performance and behavior. Men had significantly better control performance than women before and after training, but differences diminished substantially over the training period. An analysis of participants' joystick behaviors revealed that initially men and women relied on different patterns of control behaviors, but changes in these behaviors over time accounted for the reduced sex differences in performance. When we controlled for these differences in behavior, sex effects after training were no longer significant. Finally, examining the development of control performance and control behaviors of men and women categorized as initially high and low performers revealed the lower-performing women may have been controlling their ship using an approach that was very different from the men and higher-performing women. The potential problems of analyzing men and women's spatial performance as homogenous groups are discussed, as well as how these issues may account for sex differences in skilled video game performance and perhaps other domains involving spatial abilities.

  12. Symptoms of cybersex addiction can be linked to both approaching and avoiding pornographic stimuli: results from an analog sample of regular cybersex users.

    PubMed

    Snagowski, Jan; Brand, Matthias

    2015-01-01

    There is no consensus regarding the phenomenology, classification, and diagnostic criteria of cybersex addiction. Some approaches point toward similarities to substance dependencies for which approach/avoidance tendencies are crucial mechanisms. Several researchers have argued that within an addiction-related decision situation, individuals might either show tendencies to approach or avoid addiction-related stimuli. In the current study 123 heterosexual males completed an Approach-Avoidance-Task (AAT; Rinck and Becker, 2007) modified with pornographic pictures. During the AAT participants either had to push pornographic stimuli away or pull them toward themselves with a joystick. Sensitivity toward sexual excitation, problematic sexual behavior, and tendencies toward cybersex addiction were assessed with questionnaires. Results showed that individuals with tendencies toward cybersex addiction tended to either approach or avoid pornographic stimuli. Additionally, moderated regression analyses revealed that individuals with high sexual excitation and problematic sexual behavior who showed high approach/avoidance tendencies, reported higher symptoms of cybersex addiction. Analogous to substance dependencies, results suggest that both approach and avoidance tendencies might play a role in cybersex addiction. Moreover, an interaction with sensitivity toward sexual excitation and problematic sexual behavior could have an accumulating effect on the severity of subjective complaints in everyday life due to cybersex use. The findings provide further empirical evidence for similarities between cybersex addiction and substance dependencies. Such similarities could be retraced to a comparable neural processing of cybersex- and drug-related cues.

  13. Visual areas become less engaged in associative recall following memory stabilization.

    PubMed

    Nieuwenhuis, Ingrid L C; Takashima, Atsuko; Oostenveld, Robert; Fernández, Guillén; Jensen, Ole

    2008-04-15

    Numerous studies have focused on changes in the activity in the hippocampus and higher association areas with consolidation and memory stabilization. Even though perceptual areas are engaged in memory recall, little is known about how memory stabilization is reflected in those areas. Using magnetoencephalography (MEG) we investigated changes in visual areas with memory stabilization. Subjects were trained on associating a face to one of eight locations. The first set of associations ('stabilized') was learned in three sessions distributed over a week. The second set ('labile') was learned in one session just prior to the MEG measurement. In the recall session only the face was presented and subjects had to indicate the correct location using a joystick. The MEG data revealed robust gamma activity during recall, which started in early visual cortex and propagated to higher visual and parietal brain areas. The occipital gamma power was higher for the labile than the stabilized condition (time=0.65-0.9 s). Also the event-related field strength was higher during recall of labile than stabilized associations (time=0.59-1.5 s). We propose that recall of the spatial associations prior to memory stabilization involves a top-down process relying on reconstructing learned representations in visual areas. This process is reflected in gamma band activity consistent with the notion that neuronal synchronization in the gamma band is required for visual representations. More direct synaptic connections are formed with memory stabilization, thus decreasing the dependence on visual areas.

  14. Keyboard before Head Tracking Depresses User Success in Remote Camera Control

    NASA Astrophysics Data System (ADS)

    Zhu, Dingyun; Gedeon, Tom; Taylor, Ken

    In remote mining, operators of complex machinery have more tasks or devices to control than they have hands. For example, operating a rock breaker requires two handed joystick control to position and fire the jackhammer, leaving the camera control to either automatic control or require the operator to switch between controls. We modelled such a teleoperated setting by performing experiments using a simple physical game analogue, being a half size table soccer game with two handles. The complex camera angles of the mining application were modelled by obscuring the direct view of the play area and the use of a Pan-Tilt-Zoom (PTZ) camera. The camera control was via either a keyboard or via head tracking using two different sets of head gestures called “head motion” and “head flicking” for turning camera motion on/off. Our results show that the head motion control was able to provide a comparable performance to using a keyboard, while head flicking was significantly worse. In addition, the sequence of use of the three control methods is highly significant. It appears that use of the keyboard first depresses successful use of the head tracking methods, with significantly better results when one of the head tracking methods was used first. Analysis of the qualitative survey data collected supports that the worst (by performance) method was disliked by participants. Surprisingly, use of that worst method as the first control method significantly enhanced performance using the other two control methods.

  15. Brain-Machine Interface Enables Bimanual Arm Movements in Monkeys

    PubMed Central

    Ifft, Peter J.; Shokur, Solaiman; Li, Zheng; Lebedev, Mikhail A.; Nicolelis, Miguel A. L.

    2014-01-01

    Brain-machine interfaces (BMIs) are artificial systems that aim to restore sensation and movement to severely paralyzed patients. However, previous BMIs enabled only single arm functionality, and control of bimanual movements was a major challenge. Here, we developed and tested a bimanual BMI that enabled rhesus monkeys to control two avatar arms simultaneously. The bimanual BMI was based on the extracellular activity of 374–497 neurons recorded from several frontal and parietal cortical areas of both cerebral hemispheres. Cortical activity was transformed into movements of the two arms with a decoding algorithm called a 5th order unscented Kalman filter (UKF). The UKF is well-suited for BMI decoding because it accounts for both characteristics of reaching movements and their representation by cortical neurons. The UKF was trained either during a manual task performed with two joysticks or by having the monkeys passively observe the movements of avatar arms. Most cortical neurons changed their modulation patterns when both arms were engaged simultaneously. Representing the two arms jointly in a single UKF decoder resulted in improved decoding performance compared with using separate decoders for each arm. As the animals’ performance in bimanual BMI control improved over time, we observed widespread plasticity in frontal and parietal cortical areas. Neuronal representation of the avatar and reach targets was enhanced with learning, whereas pairwise correlations between neurons initially increased and then decreased. These results suggest that cortical networks may assimilate the two avatar arms through BMI control. PMID:24197735

  16. Simulation Exploration through Immersive Parallel Planes: Preprint

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Brunhart-Lupo, Nicholas; Bush, Brian W.; Gruchalla, Kenny

    We present a visualization-driven simulation system that tightly couples systems dynamics simulations with an immersive virtual environment to allow analysts to rapidly develop and test hypotheses in a high-dimensional parameter space. To accomplish this, we generalize the two-dimensional parallel-coordinates statistical graphic as an immersive 'parallel-planes' visualization for multivariate time series emitted by simulations running in parallel with the visualization. In contrast to traditional parallel coordinate's mapping the multivariate dimensions onto coordinate axes represented by a series of parallel lines, we map pairs of the multivariate dimensions onto a series of parallel rectangles. As in the case of parallel coordinates, eachmore » individual observation in the dataset is mapped to a polyline whose vertices coincide with its coordinate values. Regions of the rectangles can be 'brushed' to highlight and select observations of interest: a 'slider' control allows the user to filter the observations by their time coordinate. In an immersive virtual environment, users interact with the parallel planes using a joystick that can select regions on the planes, manipulate selection, and filter time. The brushing and selection actions are used to both explore existing data as well as to launch additional simulations corresponding to the visually selected portions of the input parameter space. As soon as the new simulations complete, their resulting observations are displayed in the virtual environment. This tight feedback loop between simulation and immersive analytics accelerates users' realization of insights about the simulation and its output.« less

  17. A brain-machine interface enables bimanual arm movements in monkeys.

    PubMed

    Ifft, Peter J; Shokur, Solaiman; Li, Zheng; Lebedev, Mikhail A; Nicolelis, Miguel A L

    2013-11-06

    Brain-machine interfaces (BMIs) are artificial systems that aim to restore sensation and movement to paralyzed patients. So far, BMIs have enabled only one arm to be moved at a time. Control of bimanual arm movements remains a major challenge. We have developed and tested a bimanual BMI that enables rhesus monkeys to control two avatar arms simultaneously. The bimanual BMI was based on the extracellular activity of 374 to 497 neurons recorded from several frontal and parietal cortical areas of both cerebral hemispheres. Cortical activity was transformed into movements of the two arms with a decoding algorithm called a fifth-order unscented Kalman filter (UKF). The UKF was trained either during a manual task performed with two joysticks or by having the monkeys passively observe the movements of avatar arms. Most cortical neurons changed their modulation patterns when both arms were engaged simultaneously. Representing the two arms jointly in a single UKF decoder resulted in improved decoding performance compared with using separate decoders for each arm. As the animals' performance in bimanual BMI control improved over time, we observed widespread plasticity in frontal and parietal cortical areas. Neuronal representation of the avatar and reach targets was enhanced with learning, whereas pairwise correlations between neurons initially increased and then decreased. These results suggest that cortical networks may assimilate the two avatar arms through BMI control. These findings should help in the design of more sophisticated BMIs capable of enabling bimanual motor control in human patients.

  18. Ecological Virtual Reality Evaluation of Neglect Symptoms (EVENS): Effects of Virtual Scene Complexity in the Assessment of Poststroke Unilateral Spatial Neglect.

    PubMed

    Ogourtsova, Tatiana; Archambault, Philippe; Sangani, Samir; Lamontagne, Anouk

    2018-01-01

    Unilateral spatial neglect (USN) is a highly prevalent and disabling poststroke impairment. USN is traditionally assessed with paper-and-pencil tests that lack ecological validity, generalization to real-life situations and are easily compensated for in chronic stages. Virtual reality (VR) can, however, counteract these limitations. We aimed to examine the feasibility of a novel assessment of USN symptoms in a functional shopping activity, the Ecological VR-based Evaluation of Neglect Symptoms (EVENS). EVENS is immersive and consists of simple and complex 3-dimensional scenes depicting grocery shopping shelves, where joystick-based object detection and navigation tasks are performed while seated. Effects of virtual scene complexity on navigational and detection abilities in patients with (USN+, n = 12) and without (USN-, n = 15) USN following a right hemisphere stroke and in age-matched healthy controls (HC, n = 9) were determined. Longer detection times, larger mediolateral deviations from ideal paths and longer navigation times were found in USN+ versus USN- and HC groups, particularly in the complex scene. EVENS detected lateralized and nonlateralized USN-related deficits, performance alterations that were dependent or independent of USN severity, and performance alterations in 3 USN- subjects versus HC. EVENS' environmental changing complexity, along with the functional tasks of far space detection and navigation can potentially be clinically relevant and warrant further empirical investigation. Findings are discussed in terms of attentional models, lateralized versus nonlateralized deficits in USN, and tasks-specific mechanisms.

  19. Symptoms of cybersex addiction can be linked to both approaching and avoiding pornographic stimuli: results from an analog sample of regular cybersex users

    PubMed Central

    Snagowski, Jan; Brand, Matthias

    2015-01-01

    There is no consensus regarding the phenomenology, classification, and diagnostic criteria of cybersex addiction. Some approaches point toward similarities to substance dependencies for which approach/avoidance tendencies are crucial mechanisms. Several researchers have argued that within an addiction-related decision situation, individuals might either show tendencies to approach or avoid addiction-related stimuli. In the current study 123 heterosexual males completed an Approach-Avoidance-Task (AAT; Rinck and Becker, 2007) modified with pornographic pictures. During the AAT participants either had to push pornographic stimuli away or pull them toward themselves with a joystick. Sensitivity toward sexual excitation, problematic sexual behavior, and tendencies toward cybersex addiction were assessed with questionnaires. Results showed that individuals with tendencies toward cybersex addiction tended to either approach or avoid pornographic stimuli. Additionally, moderated regression analyses revealed that individuals with high sexual excitation and problematic sexual behavior who showed high approach/avoidance tendencies, reported higher symptoms of cybersex addiction. Analogous to substance dependencies, results suggest that both approach and avoidance tendencies might play a role in cybersex addiction. Moreover, an interaction with sensitivity toward sexual excitation and problematic sexual behavior could have an accumulating effect on the severity of subjective complaints in everyday life due to cybersex use. The findings provide further empirical evidence for similarities between cybersex addiction and substance dependencies. Such similarities could be retraced to a comparable neural processing of cybersex- and drug-related cues. PMID:26052292

  20. Using a Low Cost Flight Simulation Environment for Interdisciplinary Education

    NASA Technical Reports Server (NTRS)

    Khan, M. Javed; Rossi, Marcia; ALi, Syed F.

    2004-01-01

    A multi-disciplinary and inter-disciplinary education is increasingly being emphasized for engineering undergraduates. However, often the focus is on interaction between engineering disciplines. This paper discusses the experience at Tuskegee University in providing interdisciplinary research experiences for undergraduate students in both Aerospace Engineering and Psychology through the utilization of a low cost flight simulation environment. The environment, which is pc-based, runs a low-cost of-the-shelf software and is configured for multiple out-of-the-window views and a synthetic heads down display with joystick, rudder and throttle controls. While the environment is being utilized to investigate and evaluate various strategies for training novice pilots, students were involved to provide them with experience in conducting such interdisciplinary research. On the global inter-disciplinary level these experiences included developing experimental designs and research protocols, consideration of human participant ethical issues, and planning and executing the research studies. During the planning phase students were apprised of the limitations of the software in its basic form and the enhancements desired to investigate human factors issues. A number of enhancements to the flight environment were then undertaken, from creating Excel macros for determining the performance of the 'pilots', to interacting with the software to provide various audio/video cues based on the experimental protocol. These enhancements involved understanding the flight model and performance, stability & control issues. Throughout this process, discussions of data analysis included a focus from a human factors perspective as well as an engineering point of view.

  1. Attentional Modulation of Eye Torsion Responses

    NASA Technical Reports Server (NTRS)

    Stevenson, Scott B.; Mahadevan, Madhumitha S.; Mulligan, Jeffrey B.

    2016-01-01

    Eye movements generally have both reflexive and voluntary aspects, but torsional eye movements are usually thought of as a reflexive response to image rotation around the line of sight (torsional OKN) or to head roll (torsional VOR). In this study we asked whether torsional responses could be modulated by attention in a case where two stimuli rotated independently, and whether attention would influence the latency of responses. The display consisted of rear-projected radial "pinwheel" gratings, with an inner annulus segment extending from the center to 22 degrees eccentricity, and an outer annulus segment extending from 22 degrees out to 45 degrees eccentricity. The two segments rotated around the center in independent random walks, stepping randomly 4 degrees clockwise or counterclockwise at 60 Hz. Subjects were asked to attend to one or the other while keeping fixation steady at the center of the display. To encourage attention on one or the other segment of the display, subjects were asked to move a joystick in synchrony with the back and forth rotations of one part of the image while ignoring the other. Eye torsion was recorded with the scleral search coil technique, sampled at 500 Hz. All four subjects showed roughly 50% stronger torsion responses to the attended compared to unattended segments. Latency varied from 100 to 150 msec across subjects and was unchanged by attention. These findings suggest that attention can influence eye movement responses that are not typically under voluntary control.

  2. Intuitive wireless control of a robotic arm for people living with an upper body disability.

    PubMed

    Fall, C L; Turgeon, P; Campeau-Lecours, A; Maheu, V; Boukadoum, M; Roy, S; Massicotte, D; Gosselin, C; Gosselin, B

    2015-08-01

    Assistive Technologies (ATs) also called extrinsic enablers are useful tools for people living with various disabilities. The key points when designing such useful devices not only concern their intended goal, but also the most suitable human-machine interface (HMI) that should be provided to users. This paper describes the design of a highly intuitive wireless controller for people living with upper body disabilities with a residual or complete control of their neck and their shoulders. Tested with JACO, a six-degree-of-freedom (6-DOF) assistive robotic arm with 3 flexible fingers on its end-effector, the system described in this article is made of low-cost commercial off-the-shelf components and allows a full emulation of JACO's standard controller, a 3 axis joystick with 7 user buttons. To do so, three nine-degree-of-freedom (9-DOF) inertial measurement units (IMUs) are connected to a microcontroller and help measuring the user's head and shoulders position, using a complementary filter approach. The results are then transmitted to a base-station via a 2.4-GHz low-power wireless transceiver and interpreted by the control algorithm running on a PC host. A dedicated software interface allows the user to quickly calibrate the controller, and translates the information into suitable commands for JACO. The proposed controller is thoroughly described, from the electronic design to implemented algorithms and user interfaces. Its performance and future improvements are discussed as well.

  3. Motor demand-dependent activation of ipsilateral motor cortex.

    PubMed

    Buetefisch, Cathrin M; Revill, Kate Pirog; Shuster, Linda; Hines, Benjamin; Parsons, Michael

    2014-08-15

    The role of ipsilateral primary motor cortex (M1) in hand motor control during complex task performance remains controversial. Bilateral M1 activation is inconsistently observed in functional (f)MRI studies of unilateral hand performance. Two factors limit the interpretation of these data. As the motor tasks differ qualitatively in these studies, it is conceivable that M1 contributions differ with the demand on skillfulness. Second, most studies lack the verification of a strictly unilateral execution of the motor task during the acquisition of imaging data. Here, we use fMRI to determine whether ipsilateral M1 activity depends on the demand for precision in a pointing task where precision varied quantitatively while movement trajectories remained equal. Thirteen healthy participants used an MRI-compatible joystick to point to targets of four different sizes in a block design. A clustered acquisition technique allowed simultaneous fMRI/EMG data collection and confirmed that movements were strictly unilateral. Accuracy of performance increased with target size. Overall, the pointing task revealed activation in contralateral and ipsilateral M1, extending into contralateral somatosensory and parietal areas. Target size-dependent activation differences were found in ipsilateral M1 extending into the temporal/parietal junction, where activation increased with increasing demand on accuracy. The results suggest that ipsilateral M1 is active during the execution of a unilateral motor task and that its activity is modulated by the demand on precision. Copyright © 2014 the American Physiological Society.

  4. Evaluation of smartphone-based interaction techniques in a CAVE in the context of immersive digital project review

    NASA Astrophysics Data System (ADS)

    George, Paul; Kemeny, Andras; Colombet, Florent; Merienne, Frédéric; Chardonnet, Jean-Rémy; Thouvenin, Indira Mouttapa

    2014-02-01

    Immersive digital project reviews consist in using virtual reality (VR) as a tool for discussion between various stakeholders of a project. In the automotive industry, the digital car prototype model is the common thread that binds them. It is used during immersive digital project reviews between designers, engineers, ergonomists, etc. The digital mockup is also used to assess future car architecture, habitability or perceived quality requirements with the aim to reduce using physical mockups for optimized cost, delay and quality efficiency. Among the difficulties identified by the users, handling the mockup is a major one. Inspired by current uses of nomad devices (multi-touch gestures, IPhone UI look'n'feel and AR applications), we designed a navigation technique taking advantage of these popular input devices: Space scrolling allows moving around the mockup. In this paper, we present the results of a study we conducted on the usability and acceptability of the proposed smartphone-based interaction metaphor compared to traditional technique and we provide indications of the most efficient choices for different use-cases accordingly. It was carried out in a traditional 4-sided CAVE and its purpose is to assess a chosen set of interaction techniques to be implemented in Renault's new 5-sides 4K x 4K wall high performance CAVE. The proposed new metaphor using nomad devices is well accepted by novice VR users and future implementation should allow an efficient industrial use. Their use is an easy and user friendly alternative of the existing traditional control devices such as a joystick.

  5. Health interest modulates brain reward responses to a perceived low-caloric beverage in females.

    PubMed

    van Rijn, Inge; Wegman, Joost; Aarts, Esther; de Graaf, Cees; Smeets, Paul A M

    2017-01-01

    Health labels are omnipresent in the supermarket. Such labels give rise to expectations about the product experience and may change flavor perception and perceived reward value. Consumers vary in their degree of health interest and may be differentially affected by such labels. However, how health interest influences neural reward responses to anticipation and receipt of heath-labeled foods is not known. This study assessed to what extent brain responses induced by anticipation and receipt of a beverage with different levels of perceived caloric content are associated with health interest. Twenty-five females completed an fMRI motivational taste-task in which they were presented with a low-caloric cue or a high-caloric cue and subsequently worked for sips of lemonade by moving a joystick. If they responded correctly and in time, they received the lemonade as a reward. Because of the 2 cue types, participants believed they were receiving 2 different lemonades, a high-caloric (HC-receipt) and a low-caloric (LC-receipt) one. Health interest was assessed with the General health interest subscale of the Health and Taste Attitude Scales. Health interest scores correlated significantly (r = .65) with LC-versus HC-receipt activation in the dorsal striatum (putamen), a region involved in encoding food reward. These findings suggest that the reward value of a healthy product compared to its unhealthy counterpart increases with health interest. This provides more insight into the working mechanism of government campaigns that focus on increasing health interest to encourage the formation of healthy eating habits. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

  6. Flight display dynamics and compensatory head movements in pilots.

    PubMed

    Beer, Jeremy; Freeman, David

    2007-06-01

    Experiments measured the optokinetic cervical reflex (OKCR), wherein the banking pilot aligns the head with the horizon. In a synthetic cockpit, the flight display was manipulated to test whether changing the visual reference frame would alter OKCR. Eight subjects (five rated pilots) flew a route in simulated visual meteorological conditions that required them to bank the aircraft frequently. Pilots' head tilt was characterized using both the conventional method of regressing against simultaneous aircraft bank, and also an event-based analysis, which identified head movements before, during, and after each turn. Three display configurations were compared to determine whether pilots' orientation would ever migrate from the horizon to the aircraft symbol. The first was a conventional "Inside-Out" condition. A "Frequency-Separated" condition combined Inside-Out horizon geometry with Outside-In dynamics for the aircraft symbol, which depicted joystick bank inputs. In the "Outside-In" condition, the aircraft symbol rolled against a static horizon. Regressions identified an interaction (p < 0.001) between display condition and aircraft bank: head tilt followed horizon tilt in Inside-Out and Frequency-Separated conditions, while remaining mostly level in the Outside-In condition. The event-based analysis identified anticipatory head movements in Inside-Out and Frequency-Separated conditions: 95% CI indicated that before each turn, head tilt favored the direction of the imminent bank. While the conventional analysis confirmed that the horizon comprises a primary spatial reference, the finer-grained event-based analysis indicated that pilots' reference can migrate at least temporarily to the vehicle, and that OKCR can be preceded by anticipatory head movements in the opposite direction.

  7. The frequency of human, manual adjustments in balancing an inverted pendulum is constrained by intrinsic physiological factors

    PubMed Central

    Loram, Ian D; Gawthrop, Peter J; Lakie, Martin

    2006-01-01

    While standing naturally and when manually or pedally balancing an equivalent inverted pendulum, the load sways slowly (characteristic unidirectional duration ∼1 s) and the controller, calf muscles or hand, makes more frequent adjustments (characteristic unidirectional duration 400 ms). Here we test the hypothesis that these durations reflect load properties rather than some intrinsic property of the human neuromuscular system. Using a specialized set-up mechanically analogous to real standing, subjects manually balanced inverted pendulums with different moments of inertia through a compliant spring representing the Achilles tendon. The spring bias was controlled by a sensitive joystick via a servo motor and accurate visual feedback was provided on an oscilloscope. As moment of inertia decreased, inverted pendulum sway size increased and it became difficult to sustain successful balance. The mean duration of unidirectional balance adjustments did not change. Moreover, the mean duration of unidirectional inverted pendulum sway reduced only slightly, remaining around 1 s. The simplest explanation is that balance was maintained by a process of manual adjustments intrinsically limited to a mean frequency of two to three unidirectional adjustments per second corresponding to intermittent control observed in manual tracking experiments. Consequently the inverted pendulum sway duration, mechanically related to the bias duration, reflects an intrinsic constraint of the neuromuscular control system. Given the similar durations of sway and muscle adjustments observed in real standing, we postulate that the characteristic duration of unidirectional standing sway reflects intrinsic intermittent control rather than the inertial properties of the body. PMID:16973712

  8. Intelligent lead: a novel HRI sensor for guide robots.

    PubMed

    Cho, Keum-Bae; Lee, Beom-Hee

    2012-01-01

    This paper addresses the introduction of a new Human Robot Interaction (HRI) sensor for guide robots. Guide robots for geriatric patients or the visually impaired should follow user's control command, keeping a certain desired distance allowing the user to work freely. Therefore, it is necessary to acquire control commands and a user's position on a real-time basis. We suggest a new sensor fusion system to achieve this objective and we will call this sensor the "intelligent lead". The objective of the intelligent lead is to acquire a stable distance from the user to the robot, speed-control volume and turn-control volume, even when the robot platform with the intelligent lead is shaken on uneven ground. In this paper we explain a precise Extended Kalman Filter (EKF) procedure for this. The intelligent lead physically consists of a Kinect sensor, the serial linkage attached with eight rotary encoders, and an IMU (Inertial Measurement Unit) and their measurements are fused by the EKF. A mobile robot was designed to test the performance of the proposed sensor system. After installing the intelligent lead in the mobile robot, several tests are conducted to verify that the mobile robot with the intelligent lead is capable of achieving its goal points while maintaining the appropriate distance between the robot and the user. The results show that we can use the intelligent lead proposed in this paper as a new HRI sensor joined a joystick and a distance measure in the mobile environments such as the robot and the user are moving at the same time.

  9. Fine-grained versus categorical: Pupil size differentiates between strategies for spatial working memory performance.

    PubMed

    Starc, Martina; Anticevic, Alan; Repovš, Grega

    2017-05-01

    Pupillometry provides an accessible option to track working memory processes with high temporal resolution. Several studies showed that pupil size increases with the number of items held in working memory; however, no study has explored whether pupil size also reflects the quality of working memory representations. To address this question, we used a spatial working memory task to investigate the relationship of pupil size with spatial precision of responses and indicators of reliance on generalized spatial categories. We asked 30 participants (15 female, aged 19-31) to remember the position of targets presented at various locations along a hidden radial grid. After a delay, participants indicated the remembered location with a high-precision joystick providing a parametric measure of trial-to-trial accuracy. We recorded participants' pupil dilations continuously during task performance. Results showed a significant relation between pupil dilation during preparation/early encoding and the precision of responses, possibly reflecting the attentional resources devoted to memory encoding. In contrast, pupil dilation at late maintenance and response predicted larger shifts of responses toward prototypical locations, possibly reflecting larger reliance on categorical representation. On an intraindividual level, smaller pupil dilations during encoding predicted larger dilations during late maintenance and response. On an interindividual level, participants relying more on categorical representation also produced larger precision errors. The results confirm the link between pupil size and the quality of spatial working memory representation. They suggest compensatory strategies of spatial working memory performance-loss of precise spatial representation likely increases reliance on generalized spatial categories. © 2017 Society for Psychophysiological Research.

  10. Cue avoidance training and inhibitory control training for the reduction of alcohol consumption: a comparison of effectiveness and investigation of their mechanisms of action.

    PubMed

    Di Lemma, Lisa C G; Field, Matt

    2017-08-01

    Both cue avoidance training (CAT) and inhibitory control training (ICT) reduce alcohol consumption in the laboratory. However, these interventions have never been directly compared and their mechanisms of action are poorly understood. We compared the effects of both types of training on alcohol consumption and investigated if they led to theoretically predicted changes in alcohol avoidance (CAT) or alcohol inhibition (ICT) associations and changes in evaluation of alcohol cues. Heavy drinking young adults (N = 120) were randomly assigned to one of four groups: (1) CAT (repeatedly pushing alcohol cues away with a joystick), (2) sham (control) CAT; (3) ICT (repeatedly inhibiting behaviour in response to alcohol cues); or (4) sham (control) ICT. Changes in reaction times and automatic evaluations of alcohol cues were assessed before and after training using assessment versions of tasks used in training and the implicit association test (IAT), respectively. Finally, participants completed a bogus taste test as a measure of ad libitum alcohol consumption. Compared to sham conditions, CAT and ICT both led to reduced alcohol consumption although there was no difference between the two. Neither intervention affected performance on the IAT, and changes in reaction time did not suggest the formation of robust alcohol avoidance (CAT) or alcohol inhibition (ICT) associations after training. CAT and ICT yielded equivalent reductions in alcohol consumption in the laboratory. However, these behavioural effects were not accompanied by devaluation of stimuli or the formation of alcohol avoidance or alcohol inhibition associations.

  11. Mind the movement: Frontal asymmetry stands for behavioral motivation, bilateral frontal activation for behavior.

    PubMed

    Rodrigues, Johannes; Müller, Mathias; Mühlberger, Andreas; Hewig, Johannes

    2018-01-01

    Frontal asymmetry has been investigated over the past 30 years, and several theories have been developed about its meaning. The original theory of Davidson and its diversification by Harmon-Jones & Allen allocated approach motivation to relative left frontal brain activity and withdrawal motivation to relative right frontal brain activity. Hewig and colleagues extended this theory by adding bilateral frontal activation representing a biological correlate of the behavioral activation system if actual behavior is shown. Wacker and colleagues formulated a theory related to the revised reinforcement sensitivity theory by Gray & McNaughton. Here, relative left frontal brain activation represents the revised behavioral activation system and behavior, while relative right frontal brain activation represents the revised behavioral inhibition system, representing the experience of conflict. These theories were investigated with a newly developed paradigm where participants were able to move around freely in a virtual T maze via joystick while having their EEG recorded. Analyzing the influence of frontal brain activation during this virtual reality task on observable behavior for 30 participants, we found more relative left frontal brain activation during approach behavior and more relative right brain activation for withdrawal behavior of any kind. Additionally, there was more bilateral frontal brain activation when participants were engaged in behavior compared to doing nothing. Hence, this study provides evidence for the idea that frontal asymmetry stands for behavioral approach or avoidance motivation, and bilateral frontal activation stands for behavior. Additionally, observable behavior is not only determined by frontal asymmetry, but also by relevant traits. © 2017 Society for Psychophysiological Research.

  12. The Effect of Approach/Avoidance Training on Alcohol Consumption Is Mediated by Change in Alcohol Action Tendency

    PubMed Central

    Sharbanee, Jason M.; Hu, Litje; Stritzke, Werner G. K.; Wiers, Reinout W.; Rinck, Mike; MacLeod, Colin

    2014-01-01

    Training people to respond to alcohol images by making avoidance joystick movements can affect subsequent alcohol consumption, and has shown initial efficacy as a treatment adjunct. However, the mechanisms that underlie the training’s efficacy are unknown. The present study aimed to determine 1) whether the training’s effect is mediated by a change in action tendency or a change in selective attention, and 2) whether the training’s effect is moderated by individual differences in working memory capacity (WMC). Three groups of social drinkers (total N = 74) completed either approach-alcohol training, avoid-alcohol training or a sham-training on the Approach-Avoidance Task (AAT). Participants’ WMC was assessed prior to training, while their alcohol-related action tendency and selective attention were assessed before and after the training on the recently developed Selective-Attention/Action Tendency Task (SA/ATT), before finally completing an alcohol taste-test. There was no significant main effect of approach/avoidance training on alcohol consumption during the taste-test. However, there was a significant indirect effect of training on alcohol consumption mediated by a change in action tendency, but no indirect effect mediated by a change in selective attention. There was inconsistent evidence of WMC moderating training efficacy, with moderation found only for the effect of approach-alcohol training on the AAT but not on the SA/ATT. Thus approach/avoidance training affects alcohol consumption specifically by changing the underlying action tendency. Multiple training sessions may be required in order to observe more substantive changes in drinking behaviour. PMID:24465750

  13. Threatening social context facilitates pain-related fear learning.

    PubMed

    Karos, Kai; Meulders, Ann; Vlaeyen, Johan W S

    2015-03-01

    This study investigated the effects of a threatening and a safe social context on learning pain-related fear, a key factor in the development and maintenance of chronic pain. We measured self-reported pain intensity, pain expectancy, pain-related fear (verbal ratings and eyeblink startle responses), and behavioral measures of avoidance (movement-onset latency and duration) using an established differential voluntary movement fear conditioning paradigm. Participants (N = 42) performed different movements with a joystick: during fear acquisition, movement in one direction (CS+) was followed by a painful stimulus (pain-US) whereas movement in another direction (CS-) was not. For participants in the threat group, an angry face was continuously presented in the background during the task, whereas in the safe group, a happy face was presented. During the extinction phase the pain-US was omitted. As compared to the safe social context, a threatening social context led to increased contextual fear and facilitated differentiation between CS+ and CS- movements regarding self-reported pain expectancy, fear of pain, eyeblink startle responses, and movement-onset latency. In contrast, self-reported pain intensity was not affected by social context. These data support the modulation of pain-related fear by social context. A threatening social context leads to stronger acquisition of (pain-related) fear and simultaneous contextual fear but does not affect pain intensity ratings. This knowledge may aid in the prevention of chronic pain and anxiety disorders and shows that social context might modulate pain-related fear without immediately affecting pain intensity itself. Copyright © 2015 American Pain Society. Published by Elsevier Inc. All rights reserved.

  14. Exoskeletal meal assistance system (EMAS II) for progressive muscle dystrophy patient.

    PubMed

    Hasegawa, Yasuhisa; Oura, Saori

    2011-01-01

    This paper introduces a 4-DOFs exoskeletal meal assistance system (EMAS II) for progressive muscle dystrophy patient. It is generally better for the patient to use his/her hands by himself in daily life because active works maintain level of residual functions, health and initiative of him/her. The EMAS II that has a new joystick-type user interface device and three-DOFs on a shoulder part is enhanced for an easier operation and more comfortable support on eating, as the succeeding model of the previous system that has two-DOFs on a shoulder. In order to control the 4-DOFs system by the simple user interface device, the EMAS II simulates upper limb motion patterns of a healthy person. The motion patterns are modeled by extracting correlations between the height of a user's wrist joint and that of the user's elbow joint at the table. Moreover, the EMAS II automatically brings user's hand up to his/her mouth or back to a table when he/she pushes a preset switch on the interface device. Therefore a user has only to control a position of his/her wrist to pick or scoop foods and then flip the switch to start automatic mode, while a height of the elbow joint is automatically controlled by the EMAS II itself. The results of experiments, where a healthy subject regarded as a muscle dystrophy patient eats a meal with EMAS II, show that the subject finished her meal in a natural way in 18 minutes 40 seconds which was within a recommended time of 30 minutes. © 2011 IEEE

  15. Development of a Rover Simulation to Assess Operational Proficiency Following Long Duration Spaceflights

    NASA Technical Reports Server (NTRS)

    DeDios, Y. E.; Dean, S. L.; Rpsemtja (. K/); < acdpig (as/ J/ G/); Moore, S. T.; Wood, S. J.

    2011-01-01

    Following long-duration space transits, adaptive changes in sensorimotor and cognitive function may impair the crew s ability to safely control pressurized rovers designed to explore the new environment. We describe a rover simulation developed to quantify post-flight decrements in operational proficiency following International Space Station expeditions. The rover simulation consists of a serial presentation of discrete tasks to be completed as quickly and accurately as possible. Each task consists of 1) perspective taking using a map that defines a docking target, 2) navigation toward the target around a Martian outpost, and 3) docking a side hatch of the rover to a visually guided target. The simulator utilizes a Stewart-type motion base (CKAS, Australia), single seat cabin with triple scene projection covering approximately 150 horizontal by 40 vertical, and joystick controller. The software was implemented using Unity3 with next-gen PhysX engine to tightly synchronize simulation and motion platform commands. Separate C# applications allow investigators to customize session sequences with different lighting and gravitational conditions, and then execute tasks to be performed as well as record performance data. Preliminary tests resulted in low incidence of motion sickness (<15% unable to complete first session), with only negligible after effects and symptoms after familiarization sessions. Functionally relevant testing early post-flight will develop evidence regarding the limitations to early surface operations and what countermeasures are needed. This approach can be easily adapted to other vehicle designs to provide a platform to safely assess how sensorimotor and cognitive function impact manual control performance.

  16. Measurement of food-related approach-avoidance biases: Larger biases when food stimuli are task relevant.

    PubMed

    Lender, Anja; Meule, Adrian; Rinck, Mike; Brockmeyer, Timo; Blechert, Jens

    2018-06-01

    Strong implicit responses to food have evolved to avoid energy depletion but contribute to overeating in today's affluent environments. The Approach-Avoidance Task (AAT) supposedly assesses implicit biases in response to food stimuli: Participants push pictures on a monitor "away" or pull them "near" with a joystick that controls a corresponding image zoom. One version of the task couples movement direction with image content-independent features, for example, pulling blue-framed images and pushing green-framed images regardless of content ('irrelevant feature version'). However, participants might selectively attend to this feature and ignore image content and, thus, such a task setup might underestimate existing biases. The present study tested this attention account by comparing two irrelevant feature versions of the task with either a more peripheral (image frame color: green vs. blue) or central (small circle vs. cross overlaid over the image content) image feature as response instruction to a 'relevant feature version', in which participants responded to the image content, thus making it impossible to ignore that content. Images of chocolate-containing foods and of objects were used, and several trait and state measures were acquired to validate the obtained biases. Results revealed a robust approach bias towards food only in the relevant feature condition. Interestingly, a positive correlation with state chocolate craving during the task was found when all three conditions were combined, indicative of criterion validity of all three versions. However, no correlations were found with trait chocolate craving. Results provide a strong case for the relevant feature version of the AAT for bias measurement. They also point to several methodological avenues for future research around selective attention in the irrelevant versions and task validity regarding trait vs. state variables. Copyright © 2018 Elsevier Ltd. All rights reserved.

  17. Comparison of the metabolic demands of dance performance using three mobility devices for a dancer with spinal cord injury and an able-bodied dancer.

    PubMed

    Mengelkoch, Larry J; Highsmith, M Jason; Morris, Merry L

    2014-09-01

    Mobility devices for dancers with physical mobility impairments have previously been limited to traditional manual or power wheelchairs. The hands-free torso-controlled mobility chair is a unique powered mobility device which allows greater freedom and expression of movement of the trunk and upper extremities. This study compared differences in energy expenditure during a standardized dance activity using three mobility devices: the hands-free torso-controlled mobility chair, a manual sports wheelchair with hand-arm control, and an electric power chair with hand-joystick control. An experienced dancer with C7 incomplete spinal cord injury (SCI) and an experienced able-bodied dancer were recruited for testing. Three measurement trials were obtained for each chair per subject. Oxygen uptake (VO2) and heart rate (HR) were measured continuously during the dance activity. Immediately following the dance activity, subjects rated perceived exertion. Significant differences (p ≤ 0.05) and similar linear patterns in VO2 and HR responses were observed between chairs for both dancers. When the hands-free mobility chair was used, the dance activity required a moderate level of energy expenditure compared to the manual sports chair or electric power chair for both dancers. Higher ratings of perceived exertion were observed in the manual chair compared to the other chairs for the dancer with SCI, but were similar between chairs for the able-bodied dancer. These results suggest that for a dancer with high-level SCI, the hands-free torso-controlled mobility chair may offer improved freedom and expressive movement possibilities and is an energy-efficient mobility device.

  18. The effect of a concurrent cognitive task on cortical potentials evoked by unpredictable balance perturbations

    PubMed Central

    Quant, Sylvia; Adkin, Allan L; Staines, W Richard; Maki, Brian E; McIlroy, William E

    2004-01-01

    Background Although previous studies suggest that postural control requires attention and other cognitive resources, the central mechanisms responsible for this relationship remain unclear. To address this issue, we examined the effects of altered attention on cortical activity and postural responses following mechanical perturbations to upright stance. We hypothesized that cortical activity would be attenuated but not delayed when mechanical perturbations were applied during a concurrent performance of a cognitive task (i.e. when attention was directed away from the perturbation). We also hypothesized that these cortical changes would be accompanied by alterations in the postural response, as evidenced by increases in the magnitude of anteroposterior (AP) centre of pressure (COP) peak displacements and tibialis anterior (TA) muscle activity. Healthy young adults (n = 7) were instructed to continuously track (cognitive task) or not track (control task) a randomly moving visual target using a hand-held joystick. During each of these conditions, unpredictable translations of a moving floor evoked cortical and postural responses. Scalp-recorded cortical activity, COP, and TA electromyographic (EMG) measures were collected. Results Results revealed a significant decrease in the magnitude of early cortical activity (the N1 response, the first negative peak after perturbation onset) during the tracking task compared to the control condition. More pronounced AP COP peak displacements and EMG magnitudes were also observed for the tracking task and were possibly related to changes in the N1 response. Conclusion Based on previous notions that the N1 response represents sensory processing of the balance disturbance, we suggest that the attenuation of the N1 response is an important central mechanism that may provide insight into the relationship between attention and postural control. PMID:15147586

  19. The effect of a concurrent cognitive task on cortical potentials evoked by unpredictable balance perturbations.

    PubMed

    Quant, Sylvia; Adkin, Allan L; Staines, W Richard; Maki, Brian E; McIlroy, William E

    2004-05-17

    Although previous studies suggest that postural control requires attention and other cognitive resources, the central mechanisms responsible for this relationship remain unclear. To address this issue, we examined the effects of altered attention on cortical activity and postural responses following mechanical perturbations to upright stance. We hypothesized that cortical activity would be attenuated but not delayed when mechanical perturbations were applied during a concurrent performance of a cognitive task (i.e. when attention was directed away from the perturbation). We also hypothesized that these cortical changes would be accompanied by alterations in the postural response, as evidenced by increases in the magnitude of anteroposterior (AP) centre of pressure (COP) peak displacements and tibialis anterior (TA) muscle activity. Healthy young adults (n = 7) were instructed to continuously track (cognitive task) or not track (control task) a randomly moving visual target using a hand-held joystick. During each of these conditions, unpredictable translations of a moving floor evoked cortical and postural responses. Scalp-recorded cortical activity, COP, and TA electromyographic (EMG) measures were collected. Results revealed a significant decrease in the magnitude of early cortical activity (the N1 response, the first negative peak after perturbation onset) during the tracking task compared to the control condition. More pronounced AP COP peak displacements and EMG magnitudes were also observed for the tracking task and were possibly related to changes in the N1 response. Based on previous notions that the N1 response represents sensory processing of the balance disturbance, we suggest that the attenuation of the N1 response is an important central mechanism that may provide insight into the relationship between attention and postural control.

  20. Robotics and systems technology for advanced endoscopic procedures: experiences in general surgery.

    PubMed

    Schurr, M O; Arezzo, A; Buess, G F

    1999-11-01

    The advent of endoscopic techniques changed surgery in many regards. This paper intends to describe an overview about technologies to facilitate endoscopic surgery. The systems described have been developed for the use in general surgery, but an easy application also in the field of cardiac surgery seems realistic. The introduction of system technology and robotic technology enables today to design a highly ergonomic solo-surgery platform. To relief the surgeon from fatigue we developed a new chair dedicated to the functional needs of endoscopic surgery. The foot pedals for high frequency, suction and irrigation are integrated into the basis of the chair. The chair is driven by electric motors controlled with an additional foot pedal joystick to achieve the desired position in the OR. A major enhancement for endoscopic technology is the introduction of robotic technology to design assisting devices for solo-surgery and manipulators for microsurgical instrumentation. A further step in the employment of robotic technology is the design of 'master-slave manipulators' to provide the surgeon with additional degrees of freedom of instrumentation. In 1996 a first prototype of an endoscopic manipulator system. named ARTEMIS, could be used in experimental applications. The system consists of a user station (master) and an instrument station (slave). The surgeon sits at a console which integrates endoscopic monitors, communication facilities and two master devices to control the two slave arms which are mounted to the operating table. Clinical use of the system, however, will require further development in the area of slave mechanics and the control system. Finally the implementation of telecommunication technology in combination with robotic instruments will open new frontiers, such as teleconsulting, teleassistance and telemanipulation.

  1. Slit lamps and lenses: a potential source of nosocomial infections?

    PubMed

    Sobolewska, Bianka; Buhl, Michael; Liese, Jan; Ziemssen, Focke

    2018-01-30

    The aim of the study was to evaluate the bacterial contamination level of contact surfaces on slit lamps and the grip areas of lenses. Within unannounced audits, two regions of the slit lamps (headrest and joystick), indirect ophthalmoscopy devices, and ultrasound probes were obtained with rayon-tipped swab. Non-contact lenses used for indirect fundoscopy were pressed on RODAC (Replicate Organism Detection and Counting) plates. One hundred and eighty-one surfaces were sampled. The total number of colony-forming units was assessed and bacterial species were identified. Spa-typing and antimicrobial susceptibility testing were performed from Staphylococcus aureus isolates. Among the total bacterial isolates from ophthalmological equipment (lenses: 51 of 78, slit lamps: 43 of 88, ophthalmoscopy helmets: 3 of 8, ultrasound probes: 2 of 7), coagulase-negative staphylococci (CNS) was most frequently found, followed by Micrococcus spp. (lenses vs. slit lamps: P < 0.001 and P = 0.01, respectively). The bacterial contamination of lenses (76%) was significantly higher than that of slit lamps (54%) (P < 0.003). A significantly higher contamination with CNS was observed on lenses from residents vs. from consultants (78% vs. 35%, P = 0.01). A total of seven different spa-types of S. aureus were isolated. No correlation was found between S. aureus contamination of different ophthalmological equipments (Spearman's rank correlation coefficient, ρ = 0.04, P = 0.75). Methicillin-resistant S. aureus was not detected. Bacterial species of the normal skin flora were isolated from the ophthalmological equipment. The bacterial contamination of the portable devices was significantly higher than that of slit lamps. Therefore, proper hygiene of the mobile instruments should be monitored in order to prevent transmission of bacteria in residents and consultants.

  2. First experience with THE AUTOLAP™ SYSTEM: an image-based robotic camera steering device.

    PubMed

    Wijsman, Paul J M; Broeders, Ivo A M J; Brenkman, Hylke J; Szold, Amir; Forgione, Antonello; Schreuder, Henk W R; Consten, Esther C J; Draaisma, Werner A; Verheijen, Paul M; Ruurda, Jelle P; Kaufman, Yuval

    2018-05-01

    Robotic camera holders for endoscopic surgery have been available for 20 years but market penetration is low. The current camera holders are controlled by voice, joystick, eyeball tracking, or head movements, and this type of steering has proven to be successful but excessive disturbance of surgical workflow has blocked widespread introduction. The Autolap™ system (MST, Israel) uses a radically different steering concept based on image analysis. This may improve acceptance by smooth, interactive, and fast steering. These two studies were conducted to prove safe and efficient performance of the core technology. A total of 66 various laparoscopic procedures were performed with the AutoLap™ by nine experienced surgeons, in two multi-center studies; 41 cholecystectomies, 13 fundoplications including hiatal hernia repair, 4 endometriosis surgeries, 2 inguinal hernia repairs, and 6 (bilateral) salpingo-oophorectomies. The use of the AutoLap™ system was evaluated in terms of safety, image stability, setup and procedural time, accuracy of imaged-based movements, and user satisfaction. Surgical procedures were completed with the AutoLap™ system in 64 cases (97%). The mean overall setup time of the AutoLap™ system was 4 min (04:08 ± 0.10). Procedure times were not prolonged due to the use of the system when compared to literature average. The reported user satisfaction was 3.85 and 3.96 on a scale of 1 to 5 in two studies. More than 90% of the image-based movements were accurate. No system-related adverse events were recorded while using the system. Safe and efficient use of the core technology of the AutoLap™ system was demonstrated with high image stability and good surgeon satisfaction. The results support further clinical studies that will focus on usability, improved ergonomics and additional image-based features.

  3. Extinction of Fear Generalization: A Comparison Between Fibromyalgia Patients and Healthy Control Participants.

    PubMed

    Meulders, Ann; Meulders, Michel; Stouten, Iris; De Bie, Jozef; Vlaeyen, Johan W S

    2017-01-01

    Fear learning deficiencies might contribute to the development and maintenance of chronic pain disability. Fear is often not restricted to movements (conditioned stimulus [CS+]) originally associated with pain (unconditioned stimulus), but expands to similar movements (generalization stimuli [GSs]). This spreading of fear becomes dysfunctional when overgeneralization to safe stimuli occurs. More importantly, persistence of pain-related fear to GSs despite corrective feedback might even be more debilitating and maintain long-term chronic pain disability. Yet, research on this topic is lacking. Using a voluntary joystick movement paradigm, we examined (extinction of) pain-related fear generalization in fibromyalgia patients (FM) and healthy control participants (HC). During acquisition, one movement (CS+) predicted pain; another did not (CS-). We tested (extinction of) fear generalization to 5 GSs varying in similarity with the CS+ and CS-. Results revealed flatter pain expectancy generalization gradients in FM than in HC due to elevated responses to GSs more similar to the CS-; the fear generalization gradients did not differ. Although pain-related fear and expectancy to the GSs decreased during extinction, responses to the GSs remained higher for FM than HC, suggesting that extinction of generalization is impaired in chronic pain patients. Persistence of excessive protective responses may contribute to maintaining long-term chronic pain disability. Pain-related fear and expectancy to movements-varying in similarity with the original painful and nonpainful movement-decrease during extinction in HC and FM. Yet, conditioned responses remain elevated in patients despite corrective feedback, indicating impaired extinction of generalization. Persistent excessive protective responses may contribute to preserving pain disability. Copyright © 2016 American Pain Society. Published by Elsevier Inc. All rights reserved.

  4. Advanced Parkinson's disease effect on goal-directed and habitual processes involved in visuomotor associative learning

    PubMed Central

    Hadj-Bouziane, Fadila; Benatru, Isabelle; Brovelli, Andrea; Klinger, Hélène; Thobois, Stéphane; Broussolle, Emmanuel; Boussaoud, Driss; Meunier, Martine

    2013-01-01

    The present behavioral study re-addresses the question of habit learning in Parkinson's disease (PD). Patients were early onset, non-demented, dopa-responsive, candidates for surgical treatment, similar to those we found earlier as suffering greater dopamine depletion in the putamen than in the caudate nucleus. The task was the same conditional associative learning task as that used previously in monkeys and healthy humans to unveil the striatum involvement in habit learning. Sixteen patients and 20 age- and education-matched healthy control subjects learned sets of 3 visuo-motor associations between complex patterns and joystick displacements during two testing sessions separated by a few hours. We distinguished errors preceding vs. following the first correct response to compare patients' performance during the earliest phase of learning dominated by goal-directed actions with that observed later on, when responses start to become habitual. The disease significantly retarded both learning phases, especially in patients under 60 years of age. However, only the late phase deficit was disease severity-dependent and persisted on the second testing session. These findings provide the first corroboration in Parkinson patients of two ideas well-established in the animal literature. The first is the idea that associating visual stimuli to motor acts is a form of habit learning that engages the striatum. It is confirmed here by the global impairment in visuo-motor learning induced by PD. The second idea is that goal-directed behaviors are predominantly caudate-dependent whereas habitual responses are primarily putamen-dependent. At the advanced PD stages tested here, dopamine depletion is greater in the putamen than in the caudate nucleus. Accordingly, the late phase of learning corresponding to the emergence of habitual responses was more vulnerable to the disease than the early phase dominated by goal-directed actions. PMID:23386815

  5. Democratizing Neurorehabilitation: How Accessible are Low-Cost Mobile-Gaming Technologies for Self-Rehabilitation of Arm Disability in Stroke?

    PubMed Central

    Rinne, Paul; Mace, Michael; Nakornchai, Tagore; Zimmerman, Karl; Fayer, Susannah; Sharma, Pankaj; Liardon, Jean-Luc; Burdet, Etienne; Bentley, Paul

    2016-01-01

    Motor-training software on tablets or smartphones (Apps) offer a low-cost, widely-available solution to supplement arm physiotherapy after stroke. We assessed the proportions of hemiplegic stroke patients who, with their plegic hand, could meaningfully engage with mobile-gaming devices using a range of standard control-methods, as well as by using a novel wireless grip-controller, adapted for neurodisability. We screened all newly-diagnosed hemiplegic stroke patients presenting to a stroke centre over 6 months. Subjects were compared on their ability to control a tablet or smartphone cursor using: finger-swipe, tap, joystick, screen-tilt, and an adapted handgrip. Cursor control was graded as: no movement (0); less than full-range movement (1); full-range movement (2); directed movement (3). In total, we screened 345 patients, of which 87 satisfied recruitment criteria and completed testing. The commonest reason for exclusion was cognitive impairment. Using conventional controls, the proportion of patients able to direct cursor movement was 38–48%; and to move it full-range was 55–67% (controller comparison: p>0.1). By comparison, handgrip enabled directed control in 75%, and full-range movement in 93% (controller comparison: p<0.001). This difference between controllers was most apparent amongst severely-disabled subjects, with 0% achieving directed or full-range control with conventional controls, compared to 58% and 83% achieving these two levels of movement, respectively, with handgrip. In conclusion, hand, or arm, training Apps played on conventional mobile devices are likely to be accessible only to mildly-disabled stroke patients. Technological adaptations such as grip-control can enable more severely affected subjects to engage with self-training software. PMID:27706248

  6. Implicit sequence-specific motor learning after sub-cortical stroke is associated with increased prefrontal brain activations: An fMRI study

    PubMed Central

    Meehan, Sean K.; Randhawa, Bubblepreet; Wessel, Brenda; Boyd, Lara A.

    2010-01-01

    Implicit motor learning is preserved after stroke, but how the brain compensates for damage to facilitate learning is unclear. We used a random effects analysis to determine how stroke alters patterns of brain activity during implicit sequence-specific motor learning as compared to general improvements in motor control. Nine healthy participants and 9 individuals with chronic, right focal sub-cortical stroke performed a continuous joystick-based tracking task during an initial fMRI session, over 5 days of practice, and a retention test during a separate fMRI session. Sequence-specific implicit motor learning was differentiated from general improvements in motor control by comparing tracking performance on a novel, repeated tracking sequences during early practice and again at the retention test. Both groups demonstrated implicit sequence-specific motor learning at the retention test, yet substantial differences were apparent. At retention, healthy control participants demonstrated increased BOLD response in left dorsal premotor cortex (BA 6) but decreased BOLD response left dorsolateral prefrontal cortex (DLPFC; BA 9) during repeated sequence tracking. In contrast, at retention individuals with stroke did not show this reduction in DLPFC during repeated tracking. Instead implicit sequence-specific motor learning and general improvements in motor control were associated with increased BOLD response in the left middle frontal gyrus BA 8, regardless of sequence type after stroke. These data emphasize the potential importance of a prefrontal-based attentional network for implicit motor learning after stroke. The present study is the first to highlight the importance of the prefrontal cortex for implicit sequence-specific motor learning after stroke. PMID:20725908

  7. Refractoriness in Sustained Visuo-Manual Control: Is the Refractory Duration Intrinsic or Does It Depend on External System Properties?

    PubMed Central

    van de Kamp, Cornelis; Gawthrop, Peter J.; Gollee, Henrik; Loram, Ian D.

    2013-01-01

    Researchers have previously adopted the double stimulus paradigm to study refractoriness in human neuromotor control. Currently, refractoriness, such as the Psychological Refractory Period (PRP) has only been quantified in discrete movement conditions. Whether refractoriness and the associated serial ballistic hypothesis generalises to sustained control tasks has remained open for more than sixty years. Recently, a method of analysis has been presented that quantifies refractoriness in sustained control tasks and discriminates intermittent (serial ballistic) from continuous control. Following our recent demonstration that continuous control of an unstable second order system (i.e. balancing a ‘virtual’ inverted pendulum through a joystick interface) is unnecessary, we ask whether refractoriness of substantial duration (∼200 ms) is evident in sustained visual-manual control of external systems. We ask whether the refractory duration (i) is physiologically intrinsic, (ii) depends upon system properties like the order (0, 1st, and 2nd) or stability, (iii) depends upon target jump direction (reversal, same direction). Thirteen participants used discrete movements (zero order system) as well as more sustained control activity (1st and 2nd order systems) to track unpredictable step-sequence targets. Results show a substantial refractory duration that depends upon system order (250, 350 and 550 ms for 0, 1st and 2nd order respectively, n = 13, p<0.05), but not stability. In sustained control refractoriness was only found when the target reverses direction. In the presence of time varying actuators, systems and constraints, we propose that central refractoriness is an appropriate control mechanism for accommodating online optimization delays within the neural circuitry including the more variable processing times of higher order (complex) input-output relations. PMID:23300430

  8. Development and content validation of the power mobility training tool.

    PubMed

    Kenyon, Lisa K; Farris, John P; Cain, Brett; King, Emily; VandenBerg, Ashley

    2018-01-01

    This paper outlines the development and content validation of the power mobility training tool (PMTT), an observational tool designed to assist therapists in developing power mobility training programs for children who have multiple, severe impairments. Initial items on the PMTT were developed based on a literature review and in consultation with therapists experienced in the use of power mobility. Items were trialled in clinical settings, reviewed, and refined. Items were then operationalized and an administration manual detailing scoring for each item was created. Qualitative and quantitative methods were used to establish content validity via a 15 member, international expert panel. The content validity ratio (CVR) was determined for each possible item. Of the 19 original items, 10 achieved minimum required CVR values and were included in the final version of the PMTT. Items related to manoeuvring a power mobility device were merged and an item related to the number of switches used concurrently to operate a power mobility device were added to the PMTT. The PMTT may assist therapists in developing training programs that facilitate the acquisition of beginning power mobility skills in children who have multiple, severe impairments. Implications for Rehabilitation The Power Mobility Training Tool (PMTT) was developed to help guide the development of power mobility intervention programs for children who have multiple, severe impairments. The PMTT can be used with children who access a power mobility device using either a joystick or a switch. Therapists who have limited experience with power mobility may find the PMTT to be helpful in setting up and conducting power mobility training interventions as a feasible aspect of a plan of care for children who have multiple, severe impairments.

  9. Interrater Reliability of the Power Mobility Road Test in the Virtual Reality-Based Simulator-2.

    PubMed

    Kamaraj, Deepan C; Dicianno, Brad E; Mahajan, Harshal P; Buhari, Alhaji M; Cooper, Rory A

    2016-07-01

    To assess interrater reliability of the Power Mobility Road Test (PMRT) when administered through the Virtual Reality-based SIMulator-version 2 (VRSIM-2). Within-subjects repeated-measures design. Participants interacted with VRSIM-2 through 2 display options (desktop monitor vs immersive virtual reality screens) using 2 control interfaces (roller system vs conventional movement-sensing joystick), providing 4 different driving scenarios (driving conditions 1-4). Participants performed 3 virtual driving sessions for each of the 2 display screens and 1 session through a real-world driving course (driving condition 5). The virtual PMRT was conducted in a simulated indoor office space, and an equivalent course was charted in an open space for the real-world assessment. After every change in driving condition, participants completed a self-reported workload assessment questionnaire, the Task Load Index, developed by the National Aeronautics and Space Administration. A convenience sample of electric-powered wheelchair (EPW) athletes (N=21) recruited at the 31st National Veterans Wheelchair Games. Not applicable. Total composite PMRT score. The PMRT had high interrater reliability (intraclass correlation coefficient [ICC]>.75) between the 2 raters in all 5 driving conditions. Post hoc analyses revealed that the reliability analyses had >80% power to detect high ICCs in driving conditions 1 and 4. The PMRT has high interrater reliability in conditions 1 and 4 and could be used to assess EPW driving performance virtually in VRSIM-2. However, further psychometric assessment is necessary to assess the feasibility of administering the PMRT using the different interfaces of VRSIM-2. Copyright © 2016 American Congress of Rehabilitation Medicine. Published by Elsevier Inc. All rights reserved.

  10. Gesture Based Control and EMG Decomposition

    NASA Technical Reports Server (NTRS)

    Wheeler, Kevin R.; Chang, Mindy H.; Knuth, Kevin H.

    2005-01-01

    This paper presents two probabilistic developments for use with Electromyograms (EMG). First described is a new-electric interface for virtual device control based on gesture recognition. The second development is a Bayesian method for decomposing EMG into individual motor unit action potentials. This more complex technique will then allow for higher resolution in separating muscle groups for gesture recognition. All examples presented rely upon sampling EMG data from a subject's forearm. The gesture based recognition uses pattern recognition software that has been trained to identify gestures from among a given set of gestures. The pattern recognition software consists of hidden Markov models which are used to recognize the gestures as they are being performed in real-time from moving averages of EMG. Two experiments were conducted to examine the feasibility of this interface technology. The first replicated a virtual joystick interface, and the second replicated a keyboard. Moving averages of EMG do not provide easy distinction between fine muscle groups. To better distinguish between different fine motor skill muscle groups we present a Bayesian algorithm to separate surface EMG into representative motor unit action potentials. The algorithm is based upon differential Variable Component Analysis (dVCA) [l], [2] which was originally developed for Electroencephalograms. The algorithm uses a simple forward model representing a mixture of motor unit action potentials as seen across multiple channels. The parameters of this model are iteratively optimized for each component. Results are presented on both synthetic and experimental EMG data. The synthetic case has additive white noise and is compared with known components. The experimental EMG data was obtained using a custom linear electrode array designed for this study.

  11. Just watching the game ain't enough: striatal fMRI reward responses to successes and failures in a video game during active and vicarious playing

    PubMed Central

    Kätsyri, Jari; Hari, Riitta; Ravaja, Niklas; Nummenmaa, Lauri

    2013-01-01

    Although the multimodal stimulation provided by modern audiovisual video games is pleasing by itself, the rewarding nature of video game playing depends critically also on the players' active engagement in the gameplay. The extent to which active engagement influences dopaminergic brain reward circuit responses remains unsettled. Here we show that striatal reward circuit responses elicited by successes (wins) and failures (losses) in a video game are stronger during active than vicarious gameplay. Eleven healthy males both played a competitive first-person tank shooter game (active playing) and watched a pre-recorded gameplay video (vicarious playing) while their hemodynamic brain activation was measured with 3-tesla functional magnetic resonance imaging (fMRI). Wins and losses were paired with symmetrical monetary rewards and punishments during active and vicarious playing so that the external reward context remained identical during both conditions. Brain activation was stronger in the orbitomedial prefrontal cortex (omPFC) during winning than losing, both during active and vicarious playing. In contrast, both wins and losses suppressed activations in the midbrain and striatum during active playing; however, the striatal suppression, particularly in the anterior putamen, was more pronounced during loss than win events. Sensorimotor confounds related to joystick movements did not account for the results. Self-ratings indicated losing to be more unpleasant during active than vicarious playing. Our findings demonstrate striatum to be selectively sensitive to self-acquired rewards, in contrast to frontal components of the reward circuit that process both self-acquired and passively received rewards. We propose that the striatal responses to repeated acquisition of rewards that are contingent on game related successes contribute to the motivational pull of video-game playing. PMID:23781195

  12. Just watching the game ain't enough: striatal fMRI reward responses to successes and failures in a video game during active and vicarious playing.

    PubMed

    Kätsyri, Jari; Hari, Riitta; Ravaja, Niklas; Nummenmaa, Lauri

    2013-01-01

    Although the multimodal stimulation provided by modern audiovisual video games is pleasing by itself, the rewarding nature of video game playing depends critically also on the players' active engagement in the gameplay. The extent to which active engagement influences dopaminergic brain reward circuit responses remains unsettled. Here we show that striatal reward circuit responses elicited by successes (wins) and failures (losses) in a video game are stronger during active than vicarious gameplay. Eleven healthy males both played a competitive first-person tank shooter game (active playing) and watched a pre-recorded gameplay video (vicarious playing) while their hemodynamic brain activation was measured with 3-tesla functional magnetic resonance imaging (fMRI). Wins and losses were paired with symmetrical monetary rewards and punishments during active and vicarious playing so that the external reward context remained identical during both conditions. Brain activation was stronger in the orbitomedial prefrontal cortex (omPFC) during winning than losing, both during active and vicarious playing. In contrast, both wins and losses suppressed activations in the midbrain and striatum during active playing; however, the striatal suppression, particularly in the anterior putamen, was more pronounced during loss than win events. Sensorimotor confounds related to joystick movements did not account for the results. Self-ratings indicated losing to be more unpleasant during active than vicarious playing. Our findings demonstrate striatum to be selectively sensitive to self-acquired rewards, in contrast to frontal components of the reward circuit that process both self-acquired and passively received rewards. We propose that the striatal responses to repeated acquisition of rewards that are contingent on game related successes contribute to the motivational pull of video-game playing.

  13. A motorized ultrasound system for MRI-ultrasound fusion guided prostatectomy

    NASA Astrophysics Data System (ADS)

    Seifabadi, Reza; Xu, Sheng; Pinto, Peter; Wood, Bradford J.

    2016-03-01

    Purpose: This study presents MoTRUS, a motorized transrectal ultrasound system, to enable remote navigation of a transrectal ultrasound (TRUS) probe during da Vinci assisted prostatectomy. MoTRUS not only provides a stable platform to the ultrasound probe, but also allows the physician to navigate it remotely while sitting on the da Vinci console. This study also presents phantom feasibility study with the goal being intraoperative MRI-US image fusion capability to bring preoperative MR images to the operating room for the best visualization of the gland, boundaries, nerves, etc. Method: A two degree-of-freedom probe holder is developed to insert and rotate a bi-plane transrectal ultrasound transducer. A custom joystick is made to enable remote navigation of MoTRUS. Safety features have been considered to avoid inadvertent risks (if any) to the patient. Custom design software has been developed to fuse pre-operative MR images to intraoperative ultrasound images acquired by MoTRUS. Results: Remote TRUS probe navigation was evaluated on a patient after taking required consents during prostatectomy using MoTRUS. It took 10 min to setup the system in OR. MoTRUS provided similar capability in addition to remote navigation and stable imaging. No complications were observed. Image fusion was evaluated on a commercial prostate phantom. Electromagnetic tracking was used for the fusion. Conclusions: Motorized navigation of the TRUS probe during prostatectomy is safe and feasible. Remote navigation provides physician with a more precise and easier control of the ultrasound image while removing the burden of manual manipulation of the probe. Image fusion improved visualization of the prostate and boundaries in a phantom study.

  14. A compact and versatile microfluidic probe for local processing of tissue sections and biological specimens

    NASA Astrophysics Data System (ADS)

    Cors, J. F.; Lovchik, R. D.; Delamarche, E.; Kaigala, G. V.

    2014-03-01

    The microfluidic probe (MFP) is a non-contact, scanning microfluidic technology for local (bio)chemical processing of surfaces based on hydrodynamically confining nanoliter volumes of liquids over tens of micrometers. We present here a compact MFP (cMFP) that can be used on a standard inverted microscope and assist in the local processing of tissue sections and biological specimens. The cMFP has a footprint of 175 × 100 × 140 mm3 and can scan an area of 45 × 45 mm2 on a surface with an accuracy of ±15 μm. The cMFP is compatible with standard surfaces used in life science laboratories such as microscope slides and Petri dishes. For ease of use, we developed self-aligned mounted MFP heads with standardized "chip-to-world" and "chip-to-platform" interfaces. Switching the processing liquid in the flow confinement is performed within 90 s using a selector valve with a dead-volume of approximately 5 μl. We further implemented height-compensation that allows a cMFP head to follow non-planar surfaces common in tissue and cellular ensembles. This was shown by patterning different macroscopic copper-coated topographies with height differences up to 750 μm. To illustrate the applicability to tissue processing, 5 μm thick M000921 BRAF V600E+ melanoma cell blocks were stained with hematoxylin to create contours, lines, spots, gradients of the chemicals, and multiple spots over larger areas. The local staining was performed in an interactive manner using a joystick and a scripting module. The compactness, user-friendliness, and functionality of the cMFP will enable it to be adapted as a standard tool in research, development and diagnostic laboratories, particularly for the interaction with tissues and cells.

  15. Social conditioning and extinction paradigm: a translational study in virtual reality.

    PubMed

    Shiban, Youssef; Reichenberger, Jonas; Neumann, Inga D; Mühlberger, Andreas

    2015-01-01

    In human beings, experiments investigating fear conditioning with social stimuli are rare. The current study aims at translating an animal model for social fear conditioning (SFC) to a human sample using an operant SFC paradigm in virtual reality. Forty participants actively (using a joystick) approached virtual male agents that served as conditioned stimuli (CS). During the acquisition phase, unconditioned stimuli (US), a combination of an air blast (5 bar, 10 ms) and a female scream (95 dB, 40 ms), were presented when participants reached a defined proximity to the agent with a contingency of 75% for CS+ agents and never for CS- agents. During the extinction and the test phases, no US was delivered. Outcome variables were pleasantness ratings and physiological reactions in heart rate (HR) and fear-potentiated startle. Additionally, the influence of social anxiety, which was measured with the Social Phobia Inventory scale, was evaluated. As expected after the acquisition phase the CS+ was rated clearly less pleasant than the CS-. This difference vanished during extinction. Furthermore, the HR remained high for the CS+, while the HR for the CS- was clearly lower after than before the acquisition. Furthermore, a clear difference between CS+ and CS- after the acquisition indicated successful conditioning on this translational measure. Contrariwise no CS+/CS- differences were observed in the physiological variables during extinction. Importantly, at the generalization test, higher socially fearful participants rated pleasantness of all agents as low whereas the lower socially fearful participants rated pleasantness as low only for the CS+. SFC was successfully induced and extinguished confirming operant conditioning in this SFC paradigm. These findings suggest that the paradigm is suitable to expand the knowledge about the learning and unlearning of social fears. Further studies should investigate the operant mechanisms of development and treatment of social anxiety disorder.

  16. sLORETA current source density analysis of evoked potentials for spatial updating in a virtual navigation task

    PubMed Central

    Nguyen, Hai M.; Matsumoto, Jumpei; Tran, Anh H.; Ono, Taketoshi; Nishijo, Hisao

    2014-01-01

    Previous studies have reported that multiple brain regions are activated during spatial navigation. However, it is unclear whether these activated brain regions are specifically associated with spatial updating or whether some regions are recruited for parallel cognitive processes. The present study aimed to localize current sources of event related potentials (ERPs) associated with spatial updating specifically. In the control phase of the experiment, electroencephalograms (EEGs) were recorded while subjects sequentially traced 10 blue checkpoints on the streets of a virtual town, which were sequentially connected by a green line, by manipulating a joystick. In the test phase of the experiment, the checkpoints and green line were not indicated. Instead, a tone was presented when the subjects entered the reference points where they were then required to trace the 10 invisible spatial reference points corresponding to the checkpoints. The vertex-positive ERPs with latencies of approximately 340 ms from the moment when the subjects entered the unmarked reference points were significantly larger in the test than in the control phases. Current source density analysis of the ERPs by standardized low-resolution brain electromagnetic tomography (sLORETA) indicated activation of brain regions in the test phase that are associated with place and landmark recognition (entorhinal cortex/hippocampus, parahippocampal and retrosplenial cortices, fusiform, and lingual gyri), detecting self-motion (posterior cingulate and posterior insular cortices), motor planning (superior frontal gyrus, including the medial frontal cortex), and regions that process spatial attention (inferior parietal lobule). The present results provide the first identification of the current sources of ERPs associated with spatial updating, and suggest that multiple systems are active in parallel during spatial updating. PMID:24624067

  17. Impact of age-related macular degeneration on object searches in realistic panoramic scenes.

    PubMed

    Thibaut, Miguel; Tran, Thi-Ha-Chau; Szaffarczyk, Sebastien; Boucart, Muriel

    2018-05-01

    This study investigated whether realistic immersive conditions with dynamic indoor scenes presented on a large, hemispheric panoramic screen covering 180° of the visual field improved the visual search abilities of participants with age-related macular degeneration (AMD). Twenty-one participants with AMD, 16 age-matched controls and 16 young observers were included. Realistic indoor scenes were presented on a panoramic five metre diameter screen. Twelve different objects were used as targets. The participants were asked to search for a target object, shown on paper before each trial, within a room composed of various objects. A joystick was used for navigation within the scene views. A target object was present in 24 trials and absent in 24 trials. The percentage of correct detection of the target, the percentage of false alarms (that is, the detection of the target when it was absent), the number of scene views explored and the search time were measured. The search time was slower for participants with AMD than for the age-matched controls, who in turn were slower than the young participants. The participants with AMD were able to accomplish the task with a performance of 75 per cent correct detections. This was slightly lower than older controls (79.2 per cent) while young controls were at ceiling (91.7 per cent). Errors were mainly due to false alarms resulting from confusion between the target object and another object present in the scene in the target-absent trials. The outcomes of the present study indicate that, under realistic conditions, although slower than age-matched, normally sighted controls, participants with AMD were able to accomplish visual searches of objects with high accuracy. © 2017 Optometry Australia.

  18. Functional brain imaging of a complex navigation task following one night of total sleep deprivation

    NASA Technical Reports Server (NTRS)

    Strangman, Gary; Thompson, John H.; Strauss, Monica M.; Marshburn, Thomas H.; Sutton, Jeffrey P.

    2006-01-01

    Study Objectives: To assess the cerebral effects associated with sleep deprivation in a simulation of a complex, real-world, high-risk task. Design and Interventions: A two-week, repeated measures, cross-over experimental protocol, with counterbalanced orders of normal sleep (NS) and total sleep deprivation (TSD). Setting: Each subject underwent functional magnetic resonance imaging (fMRI) while performing a dual-joystick, 3D sensorimotor navigation task (simulated orbital docking). Scanning was performed twice per subject, once following a night of normal sleep (NS), and once following a single night of total sleep deprivation (TSD). Five runs (eight 24s docking trials each) were performed during each scanning session. Participants: Six healthy, young, right-handed volunteers (2 women; mean age 20) participated. Measurements and Results: Behavioral performance on multiple measures was comparable in the two sleep conditions. Neuroimaging results within sleep conditions revealed similar locations of peak activity for NS and TSD, including left sensorimotor cortex, left precuneus (BA 7), and right visual areas (BA 18/19). However, cerebral activation following TSD was substantially larger and exhibited higher amplitude modulations from baseline. When directly comparing NS and TSD, most regions exhibited TSD>NS activity, including multiple prefrontal cortical areas (BA 8/9,44/45,47), lateral parieto-occipital areas (BA 19/39, 40), superior temporal cortex (BA 22), and bilateral thalamus and amygdala. Only left parietal cortex (BA 7) demonstrated NS>TSD activity. Conclusions: The large network of cerebral differences between the two conditions, even with comparable behavioral performance, suggests the possibility of detecting TSD-induced stress via functional brain imaging techniques on complex tasks before stress-induced failures.

  19. Operating Small Sat Swarms as a Single Entity: Introducing SODA

    NASA Technical Reports Server (NTRS)

    Conn, Tracie; Dono Perez, Andres

    2017-01-01

    Swarm concepts are a growing topic of interest in the small satellite community. Compared to a small satellite constellation, a swarm has the distinction of being multiple spacecraft in close proximity, in approximately the same orbit. Furthermore, we envision swarms to have capabilities for cross-link communication and station-keeping. Of particular interest is a means to maintain operator-specified geometry, alignment, and/or separation.From NASA's decadal survey, it is clear that simultaneous measurements from a 3D volume of space are desired for a variety of Earth scientific studies. As this mission concept is ultimately extended to deep space, some degree of local control for the swarm to self-correct its configuration is required. We claim that the practicality of ground commanding each individual satellite in the swarm is simply not a feasible concept of operations. In other words, the current state-of-practice does not scale to very large swarms (e.g. 100 spacecraft or more) without becoming cost prohibitive. To contain the operations costs and complexity, a new approach is required: the swarm must be operated as a unit, responding to high-level specifications for relative position and velocity.The Mission Design Division at NASA Ames Research Center is looking to the near future for opportunities to develop satellite swarm technology. As part of this effort, we are developing SODA (Swarm Orbital Dynamics Advisor), a tool that provides the orbital maneuvers required to achieve a desired type of relative swarm motion. The purpose of SODA is two-fold. First, it encompasses the algorithms and orbital dynamics model to enable the desired relative motion of the swarm satellites. The process starts with the user specifying the properties of a swarm configuration. This could be as simple as varying in-track spacing of the swarm in one orbit, or as complex as maintaining a specified 3D geometrical orientation. We presume that science objectives will drive this choice. Given these inputs, the tool provides the most efficient maneuver(s) to achieve the objective.Second, SODA provides a variety of visualization tools. We acknowledge that the relationship between a desired relative motion amongst the swarm, and the corresponding orbital parameters for each individual satellite may not be immediately apparent for ground controllers and mission planners. The purpose of SODA's visualization tools is to illustrate this concept clearly with a variety of graphics and animations. After computing the optimal orbital maneuvers to modify the swarm, these results are simulated to demonstrate successful swarm control.Our emphasis in this paper is on the importance of relating the desired motion of the swarm satellites relative to one another with the required orbital element changes. One cannot joystick a drifting swarm satellite back into position; the underlying orbital mechanics dictate the most efficient recovery maneuvers. To illustrate this point, results from several case study simulations are presented. We conclude with our forward work for ongoing SODA development and potential science applications.

  20. NPLOT - NASTRAN PLOT

    NASA Technical Reports Server (NTRS)

    Mcentire, K.

    1994-01-01

    NPLOT is an interactive computer graphics program for plotting undeformed and deformed NASTRAN finite element models (FEMs). Although there are many commercial codes already available for plotting FEMs, these have limited use due to their cost, speed, and lack of features to view BAR elements. NPLOT was specifically developed to overcome these limitations. On a vector type graphics device the two best ways to show depth are by hidden line plotting or haloed line plotting. A hidden line algorithm generates views of models with all hidden lines removed, and a haloed line algorithm displays views with aft lines broken in order to show depth while keeping the entire model visible. A haloed line algorithm is especially useful for plotting models composed of many line elements and few surface elements. The most important feature of NPLOT is its ability to create both hidden line and haloed line views accurately and much more quickly than with any other existing hidden or haloed line algorithms. NPLOT is also capable of plotting a normal wire frame view to display all lines of a model. NPLOT is able to aid in viewing all elements, but it has special features not generally available for plotting BAR elements. These features include plotting of TRUE LENGTH and NORMALIZED offset vectors and orientation vectors. Standard display operations such as rotation and perspective are possible, but different view planes such as X-Y, Y-Z, and X-Z may also be selected. Another display option is the Z-axis cut which allows a portion of the fore part of the model to be cut away to reveal details of the inside of the model. A zoom function is available to terminals with a locator (graphics cursor, joystick, etc.). The user interface of NPLOT is designed to make the program quick and easy to use. A combination of menus and commands with help menus for detailed information about each command allows experienced users greater speed and efficiency. Once a plot is on the screen the interface becomes command driven, enabling the user to manipulate the display or execute a command without having to return to the menu. NPLOT is also able to plot deformed shapes allowing it to perform post-processing. The program can read displacements, either static displacements or eigenvectors, from a MSC/NASTRAN F06 file or a UAI/NASTRAN PRT file. The displacements are written into a unformatted scratch file where they are available for rapid access when the user wishes to display a deformed shape. All subcases or mode shapes can be read in at once. Then it is easy to enable the deformed shape, to change subcases or mode shapes and to change the scale factor for subsequent plots. NPLOT is written in VAX FORTRAN for DEC VAX series computers running VMS. As distributed, the NPLOT source code makes calls to the DI3000 graphics package from Precision Visuals; however, a set of interface routines is provided to translate the DI3000 calls into Tektronix PLOT10/TCS graphics library calls so that NPLOT can use the standard Tektronix 4010 which many PC terminal emulation software programs support. NPLOT is available in VAX BACKUP format on a 9-track 1600 BPI DEC VAX BACKUP format magnetic tape (standard media) or a TK50 tape cartridge. This program was developed in 1991. DEC, VAX, VMS, and TK50 are trademarks of Digital Equipment Corporation. Tektronix, PLOT10, and TCS are trademarks of Tektronix, Inc. DI3000 is a registered trademark of Precision Visuals, Inc. NASTRAN is a registered trademark of the National Aeronautics and Space Administration. MSC/ is a trademark of MacNeal-Schwendler Corporation. UAI is a trademark of Universal Analytics, Inc.

  1. Should surgical novices trade their retractors for joysticks? Videogame experience decreases the time needed to acquire surgical skills.

    PubMed

    Shane, Matthew D; Pettitt, Barbara J; Morgenthal, Craig B; Smith, C Daniel

    2008-05-01

    Video game experience (VGE) has been identified as a possible predictive factor for surgical skill. We hypothesized that surgical novices with previous VGE would acquire new surgical skills faster than those without. Fourth-year medical students (M4) and first-year surgical residents (PG-1) completed a survey asking about standard demographic data and previous VGE. Gamers had high VGE, defined as more than 3 h per week of videogame playing. Nongamers had little or no VGE. Both groups trained to proficiency on two tasks (AcquirePlace and Traversal) of the MIST-VR simulator, with proficiency defined as meeting previously validated criteria on two consecutive trials. The number of trials required to achieve proficiency for each task was recorded. The 26 participants included 11 M4s and 15 PG-1s: 17 males (8 gamers/9 nongamers) and 9 females (3 gamers/6 nongamers), mean age 27.8 years. There were no differences in time to proficiency between the M4 and PG-1 residents, and there were no significant differences in the relative number of gamers per gender. All participants eventually met proficiency criteria. The 11 gamers reached proficiency more quickly than the 15 nongamers (median 0 trials versus 6 trials, p = 0.01). Gamers scored lower than nongamers on their initial attempts. Women overall took longer to reach proficiency than did men (median 10 trials versus 0 trials, p = 0.002). When stratified according to VGE, female nongamers took longer to reach proficiency than male nongamers (median 11 trials versus 1 trial, p = 0.006) but among gamers, there was no difference between females and males (median 0 trials versus 0.5 trials, NS). Previous VGE shortens time to achieve proficiency on two tasks on a validated surgical simulator. The possibility that VGE may ameliorate gender differences in length of time required to acquire surgical skills should be explored further.

  2. Application of auditory signals to the operation of an agricultural vehicle: results of pilot testing.

    PubMed

    Karimi, D; Mondor, T A; Mann, D D

    2008-01-01

    The operation of agricultural vehicles is a multitask activity that requires proper distribution of attentional resources. Human factors theories suggest that proper utilization of the operator's sensory capacities under such conditions can improve the operator's performance and reduce the operator's workload. Using a tractor driving simulator, this study investigated whether auditory cues can be used to improve performance of the operator of an agricultural vehicle. Steering of a vehicle was simulated in visual mode (where driving error was shown to the subject using a lightbar) and in auditory mode (where a pair of speakers were used to convey the driving error direction and/or magnitude). A secondary task was also introduced in order to simulate the monitoring of an attached machine. This task included monitoring of two identical displays, which were placed behind the simulator, and responding to them, when needed, using a joystick. This task was also implemented in auditory mode (in which a beep signaled the subject to push the proper button when a response was needed) and in visual mode (in which there was no beep and visual, monitoring of the displays was necessary). Two levels of difficulty of the monitoring task were used. Deviation of the simulated vehicle from a desired straight line was used as the measure of performance in the steering task, and reaction time to the displays was used as the measure of performance in the monitoring task. Results of the experiments showed that steering performance was significantly better when steering was a visual task (driving errors were 40% to 60% of the driving errors in auditory mode), although subjective evaluations showed that auditory steering could be easier, depending on the implementation. Performance in the monitoring task was significantly better for auditory implementation (reaction time was approximately 6 times shorter), and this result was strongly supported by subjective ratings. The majority of the subjects preferred the combination of visual mode for the steering task and auditory mode for the monitoring task.

  3. Self-affirmation improves self-control over snacking among participants low in eating self-efficacy.

    PubMed

    Churchill, Susan; Jessop, Donna C; Green, Ricky; Harris, Peter R

    2018-04-01

    Individuals low in eating self-efficacy are at particular risk of engaging in unhealthy eating behaviours, including the consumption of high calorie snacks. The elevated levels of snacking displayed by these individuals can largely be attributed to their experiencing low self-control over the avoidance of such foods (Hankonen, Kinnunen, Absetz, & Jallinoja, 2014). Interventions are thus required to boost self-control over snacking among those low in eating self-efficacy. Self-affirmation has been shown to boost self-control among individuals with depleted resources in other domains (Schmeichel & Vohs, 2009). The purpose of the current study was to test the hypothesis that a self-affirmation manipulation would similarly increase self-control over snacking for individuals low in eating self-efficacy. At baseline, participants (N = 70) completed measures of dietary restraint and eating self-efficacy. In the main study, participants completed either a self-affirmation or a control task immediately before undertaking a joystick category judgment task that assessed self-control over snacking. Hierarchical multiple regression analysis revealed the predicted significant interaction between eating self-efficacy and self-affirmation, demonstrating that self-affirmation moderated the association between eating self-efficacy and self-control over snacking. Johnson-Neyman regions of significance confirmed that for participants low in eating self-efficacy the self-affirmation manipulation resulted in higher levels of self-control. Unexpectedly, however, for participants high in eating self-efficacy the self-affirmation manipulation was found to be associated with lower levels of self-control. Findings supported the hypothesis that a self-affirmation manipulation would boost self-control over snacking among individuals low in eating self-efficacy. Self-affirmation may thus provide a useful technique for strengthening self-control in relation to the avoidance of unhealthy foods among individuals who find it difficult to manage challenging dietary situations. Copyright © 2018 Elsevier Ltd. All rights reserved.

  4. Comparison of seating, powered characteristics and functions and costs of electrically powered wheelchairs in a general population of users.

    PubMed

    Dolan, Michael John; Bolton, Megan Jennifer; Henderson, Graham Iain

    2017-10-26

    To profile and compare the seating and powered characteristics and functions of electrically powered wheelchairs (EPWs) in a general user population including equipment costs. Case notes of adult EPW users of a regional NHS service were reviewed retrospectively. Seating equipment complexity and type were categorized using the Edinburgh classification. Powered characteristics and functions, including control device type, were recorded. 482 cases were included; 53.9% female; mean duration EPW use 8.1 years (SD 7.4); rear wheel drive 88.0%; hand joystick 94.8%. Seating complexity: low 73.2%, medium 18.0%, high 8.7%. Most prevalent diagnoses: multiple sclerosis (MS) 25.3%, cerebral palsy (CP) 18.7%, muscular dystrophy (8.5%). Compared to CP users, MS users were significantly older at first use, less experienced, more likely to have mid-wheel drive and less complex seating. Additional costs for muscular dystrophy and spinal cord injury users were 3-4 times stroke users. This is the first large study of a general EPW user population using a seating classification. Significant differences were found between diagnostic groups; nevertheless, there was also high diversity within each group. The differences in provision and the equipment costs across diagnostic groups can be used to improve service planning. Implications for Rehabilitation At a service planning level, knowledge of a population's diagnostic group and age distribution can be used to inform decisions about the number of required EPWs and equipment costs. At a user level, purchasing decisions about powered characteristics and functions of EPWs and specialised seating equipment need to be taken on a case by case basis because of the diversity of users' needs within diagnostic groups. The additional equipment costs for SCI and MD users are several times those of stroke users and add between 60 and 70% of the cost of basic provision.

  5. Assessment of Spatial Navigation and Docking Performance During Simulated Rover Tasks

    NASA Technical Reports Server (NTRS)

    Wood, S. J.; Dean, S. L.; De Dios, Y. E.; Moore, S. T.

    2010-01-01

    INTRODUCTION: Following long-duration exploration transits, pressurized rovers will enhance surface mobility to explore multiple sites across Mars and other planetary bodies. Multiple rovers with docking capabilities are envisioned to expand the range of exploration. However, adaptive changes in sensorimotor and cognitive function may impair the crew s ability to safely navigate and perform docking tasks shortly after transition to the new gravitoinertial environment. The primary goal of this investigation is to quantify post-flight decrements in spatial navigation and docking performance during a rover simulation. METHODS: Eight crewmembers returning from the International Space Station will be tested on a motion simulator during four pre-flight and three post-flight sessions over the first 8 days following landing. The rover simulation consists of a serial presentation of discrete tasks to be completed within a scheduled 10 min block. The tasks are based on navigating around a Martian outpost spread over a 970 sq m terrain. Each task is subdivided into three components to be performed as quickly and accurately as possible: (1) Perspective taking: Subjects use a joystick to indicate direction of target after presentation of a map detailing current orientation and location of the rover with the task to be performed. (2) Navigation: Subjects drive the rover to the desired location while avoiding obstacles. (3) Docking: Fine positioning of the rover is required to dock with another object or align a camera view. Overall operator proficiency will be based on how many tasks the crewmember can complete during the 10 min time block. EXPECTED RESULTS: Functionally relevant testing early post-flight will develop evidence regarding the limitations to early surface operations and what countermeasures are needed. This approach can be easily adapted to a wide variety of simulated vehicle designs to provide sensorimotor assessments for other operational and civilian populations.

  6. Effects of mediated social touch on affective experiences and trust.

    PubMed

    Erk, Stefanie M; Toet, Alexander; Van Erp, Jan B F

    2015-01-01

    This study investigated whether communication via mediated hand pressure during a remotely shared experience (watching an amusing video) can (1) enhance recovery from sadness, (2) enhance the affective quality of the experience, and (3) increase trust towards the communication partner. Thereto participants first watched a sad movie clip to elicit sadness, followed by a funny one to stimulate recovery from sadness. While watching the funny clip they signaled a hypothetical fellow participant every time they felt amused. In the experimental condition the participants responded by pressing a hand-held two-way mediated touch device (a Frebble), which also provided haptic feedback via simulated hand squeezes. In the control condition they responded by pressing a button and they received abstract visual feedback. Objective (heart rate, galvanic skin conductance, number and duration of joystick or Frebble presses) and subjective (questionnaires) data were collected to assess the emotional reactions of the participants. The subjective measurements confirmed that the sad movie successfully induced sadness while the funny movie indeed evoked more positive feelings. Although their ranking agreed with the subjective measurements, the physiological measurements confirmed this conclusion only for the funny movie. The results show that recovery from movie induced sadness, the affective experience of the amusing movie, and trust towards the communication partner did not differ between both experimental conditions. Hence, feedback via mediated hand touching did not enhance either of these factors compared to visual feedback. Further analysis of the data showed that participants scoring low on Extraversion (i.e., persons that are more introvert) or low on Touch Receptivity (i.e., persons who do not like to be touched by others) felt better understood by their communication partner when receiving mediated touch feedback instead of visual feedback, while the opposite was found for participants scoring high on these factors. The implications of these results for further research are discussed, and some suggestions for follow-up experiments are presented.

  7. Effects of Frequency and Motion Paradigm on Perception of Tilt and Translation During Periodic Linear Acceleration

    NASA Technical Reports Server (NTRS)

    Beaton, K. H.; Holly, J. E.; Clement, G. R.; Wood, Scott J.

    2009-01-01

    Previous studies have demonstrated an effect of frequency on the gain of tilt and translation perception. Results from different motion paradigms are often combined to extend the stimulus frequency range. For example, Off-Vertical Axis Rotation (OVAR) and Variable Radius Centrifugation (VRC) are useful to test low frequencies of linear acceleration at amplitudes that would require impractical sled lengths. The purpose of this study was to compare roll-tilt and lateral translation motion perception in 12 healthy subjects across four paradigms: OVAR, VRC, sled translation and rotation about an earth-horizontal axis. Subjects were oscillated in darkness at six frequencies from 0.01875 to 0.6 Hz (peak acceleration equivalent to 10 deg, less for sled motion below 0.15 Hz). Subjects verbally described the amplitude of perceived tilt and translation, and used a joystick to indicate the direction of motion. Consistent with previous reports, tilt perception gain decreased as a function of stimulus frequency in the motion paradigms without concordant canal tilt cues (OVAR, VRC and Sled). Translation perception gain was negligible at low stimulus frequencies and increased at higher frequencies. There were no significant differences between the phase of tilt and translation, nor did the phase significantly vary across stimulus frequency. There were differences in perception gain across the different paradigms. Paradigms that included actual tilt stimuli had the larger tilt gains, and paradigms that included actual translation stimuli had larger translation gains. In addition, the frequency at which there was a crossover of tilt and translation gains appeared to vary across motion paradigm between 0.15 and 0.3 Hz. Since the linear acceleration in the head lateral plane was equivalent across paradigms, differences in gain may be attributable to the presence of linear accelerations in orthogonal directions and/or cognitive aspects based on the expected motion paths.

  8. Social conditioning and extinction paradigm: a translational study in virtual reality

    PubMed Central

    Shiban, Youssef; Reichenberger, Jonas; Neumann, Inga D.; Mühlberger, Andreas

    2015-01-01

    In human beings, experiments investigating fear conditioning with social stimuli are rare. The current study aims at translating an animal model for social fear conditioning (SFC) to a human sample using an operant SFC paradigm in virtual reality. Forty participants actively (using a joystick) approached virtual male agents that served as conditioned stimuli (CS). During the acquisition phase, unconditioned stimuli (US), a combination of an air blast (5 bar, 10 ms) and a female scream (95 dB, 40 ms), were presented when participants reached a defined proximity to the agent with a contingency of 75% for CS+ agents and never for CS– agents. During the extinction and the test phases, no US was delivered. Outcome variables were pleasantness ratings and physiological reactions in heart rate (HR) and fear-potentiated startle. Additionally, the influence of social anxiety, which was measured with the Social Phobia Inventory scale, was evaluated. As expected after the acquisition phase the CS+ was rated clearly less pleasant than the CS–. This difference vanished during extinction. Furthermore, the HR remained high for the CS+, while the HR for the CS– was clearly lower after than before the acquisition. Furthermore, a clear difference between CS+ and CS– after the acquisition indicated successful conditioning on this translational measure. Contrariwise no CS+/CS– differences were observed in the physiological variables during extinction. Importantly, at the generalization test, higher socially fearful participants rated pleasantness of all agents as low whereas the lower socially fearful participants rated pleasantness as low only for the CS+. SFC was successfully induced and extinguished confirming operant conditioning in this SFC paradigm. These findings suggest that the paradigm is suitable to expand the knowledge about the learning and unlearning of social fears. Further studies should investigate the operant mechanisms of development and treatment of social anxiety disorder. PMID:25904889

  9. Social Fear Conditioning Paradigm in Virtual Reality: Social vs. Electrical Aversive Conditioning

    PubMed Central

    Reichenberger, Jonas; Porsch, Sonja; Wittmann, Jasmin; Zimmermann, Verena; Shiban, Youssef

    2017-01-01

    In a previous study we could show that social fear can be induced and extinguished using virtual reality (VR). In the present study, we aimed to investigate the belongingness effect in an operant social fear conditioning (SFC) paradigm which consisted of an acquisition and an extinction phase. Forty-three participants used a joystick to approach different virtual male agents that served as conditioned stimuli. Participants were randomly allocated to one of two experimental conditions. In the electroshock condition, the unconditioned stimulus (US) used during acquisition was an electric stimulation. In the social threat condition, the US consisted of an offense: a spit in the face, mimicked by a sound and a weak air blast to the participant’s neck combined with an insult. In both groups the US was presented when participants were close to the agent (75% contingency for CS+). Outcome variables included subjective, psychophysiological and behavioral data. As expected, fear and contingency ratings increased significantly during acquisition and the differentiation between CS+ and CS- vanished during extinction. Furthermore, a clear difference in skin conductance between CS+ and CS- at the beginning of the acquisition indicated that SFC had been successful. However, a fast habituation to the US was found toward the end of the acquisition phase for the physiological response. Furthermore, participants showed avoidance behavior toward CS+ in both conditions. The results show that social fear can successfully be induced and extinguished in VR in a human sample. Thus, our paradigm can help to gain insight into learning and unlearning of social fear. Regarding the belongingness effect, the social threat condition benefits from a better differentiation between the aversive and the non-aversive stimuli. As next step we suggest comparing social-phobic patients to healthy controls in order to investigate possible differences in discrimination learning and to foster the development of more efficient treatments for social phobia. PMID:29250000

  10. Import and visualization of clinical medical imagery into multiuser VR environments

    NASA Astrophysics Data System (ADS)

    Mehrle, Andreas H.; Freysinger, Wolfgang; Kikinis, Ron; Gunkel, Andreas; Kral, Florian

    2005-03-01

    The graphical representation of three-dimensional data obtained from tomographic imaging has been the central problem since this technology is available. Neither the representation as a set of two-dimensional slices nor the 2D projection of three-dimensional models yields satisfactory results. In this paper a way is outlined which permits the investigation of volumetric clinical data obtained from standard CT, MR, PET, SPECT or experimental very high resolution CT-scanners in a three dimensional environment within a few worksteps. Volumetric datasets are converted into surface data (segmentation process) using the 3D-Slicer software tool and saved as .vtk files and exported as a collection of primitives in any common file format (.iv, .pfb). Subsequently this files can be displayed and manipulated in the CAVE virtual reality center. The CAVE is a multiuser walkable virtual room consisting of several walls on which stereoscopic images are projected by rear panel beamers. Adequate tracking of the head position and separate image calculation for each eye yields a vivid impression for one or several users. With the use of a seperately tracked 6D joystick manipulations such as rotation, translation, zooming, decomposition or highlighting can be done intuitively. The usage of the CAVE technology opens new possibilities especially in surgical training ("hands-on-effect") and as an educational tool (availability of pathological data). Unlike concurring technologies the CAVE permits a walk-through into the virtual scene but preserves enough physical perception to allow interaction between multiple users, e.g. gestures and movements. By training in a virtual environment on one hand the learning process of students in complex anatomic findings may be improved considerably and on the other hand unaccustomed views such as the one through a microscope or endoscope can be trained in advance. The availability of low-cost PC based CAVE-like systems and the rapidly decreasing price of high-performance video beamers makes the CAVE an affordable alternative to conventional surgical training techniques and without limitations in handling cadavers.

  11. Social Fear Conditioning Paradigm in Virtual Reality: Social vs. Electrical Aversive Conditioning.

    PubMed

    Reichenberger, Jonas; Porsch, Sonja; Wittmann, Jasmin; Zimmermann, Verena; Shiban, Youssef

    2017-01-01

    In a previous study we could show that social fear can be induced and extinguished using virtual reality (VR). In the present study, we aimed to investigate the belongingness effect in an operant social fear conditioning (SFC) paradigm which consisted of an acquisition and an extinction phase. Forty-three participants used a joystick to approach different virtual male agents that served as conditioned stimuli. Participants were randomly allocated to one of two experimental conditions. In the electroshock condition, the unconditioned stimulus (US) used during acquisition was an electric stimulation. In the social threat condition, the US consisted of an offense: a spit in the face, mimicked by a sound and a weak air blast to the participant's neck combined with an insult. In both groups the US was presented when participants were close to the agent (75% contingency for CS+). Outcome variables included subjective, psychophysiological and behavioral data. As expected, fear and contingency ratings increased significantly during acquisition and the differentiation between CS+ and CS- vanished during extinction. Furthermore, a clear difference in skin conductance between CS+ and CS- at the beginning of the acquisition indicated that SFC had been successful. However, a fast habituation to the US was found toward the end of the acquisition phase for the physiological response. Furthermore, participants showed avoidance behavior toward CS+ in both conditions. The results show that social fear can successfully be induced and extinguished in VR in a human sample. Thus, our paradigm can help to gain insight into learning and unlearning of social fear. Regarding the belongingness effect, the social threat condition benefits from a better differentiation between the aversive and the non-aversive stimuli. As next step we suggest comparing social-phobic patients to healthy controls in order to investigate possible differences in discrimination learning and to foster the development of more efficient treatments for social phobia.

  12. Feature determination from powered wheelchair user joystick input characteristics for adapting driving assistance.

    PubMed

    Gillham, Michael; Pepper, Matthew; Kelly, Steve; Howells, Gareth

    2017-01-01

    Background : Many powered wheelchair users find their medical condition and their ability to drive the wheelchair will change over time. In order to maintain their independent mobility, the powered chair will require adjustment over time to suit the user's needs, thus regular input from healthcare professionals is required. These limited resources can result in the user having to wait weeks for appointments, resulting in the user losing independent mobility, consequently affecting their quality of life and that of their family and carers. In order to provide an adaptive assistive driving system, a range of features need to be identified which are suitable for initial system setup and can automatically provide data for re-calibration over the long term. Methods : A questionnaire was designed to collect information from powered wheelchair users with regard to their symptoms and how they changed over time. Another group of volunteer participants were asked to drive a test platform and complete a course which represented manoeuvring in a very confined space as quickly as possible. Two of those participants were also monitored over a longer period in their normal home daily environment. Features, thought to be suitable, were examined using pattern recognition classifiers to determine their suitability for identifying the changing user input over time. Results : The results are not designed to provide absolute insight into the individual user behaviour, as no ground truth of their ability has been determined, they do nevertheless demonstrate the utility of the measured features to provide evidence of the users' changing ability over time whilst driving a powered wheelchair. Conclusions : Determining the driving features and adjustable elements provides the initial step towards developing an adaptable assistive technology for the user when the ground truths of the individual and their machine have been learned by a smart pattern recognition system.

  13. Effects of mediated social touch on affective experiences and trust

    PubMed Central

    Erk, Stefanie M.; Van Erp, Jan B.F.

    2015-01-01

    This study investigated whether communication via mediated hand pressure during a remotely shared experience (watching an amusing video) can (1) enhance recovery from sadness, (2) enhance the affective quality of the experience, and (3) increase trust towards the communication partner. Thereto participants first watched a sad movie clip to elicit sadness, followed by a funny one to stimulate recovery from sadness. While watching the funny clip they signaled a hypothetical fellow participant every time they felt amused. In the experimental condition the participants responded by pressing a hand-held two-way mediated touch device (a Frebble), which also provided haptic feedback via simulated hand squeezes. In the control condition they responded by pressing a button and they received abstract visual feedback. Objective (heart rate, galvanic skin conductance, number and duration of joystick or Frebble presses) and subjective (questionnaires) data were collected to assess the emotional reactions of the participants. The subjective measurements confirmed that the sad movie successfully induced sadness while the funny movie indeed evoked more positive feelings. Although their ranking agreed with the subjective measurements, the physiological measurements confirmed this conclusion only for the funny movie. The results show that recovery from movie induced sadness, the affective experience of the amusing movie, and trust towards the communication partner did not differ between both experimental conditions. Hence, feedback via mediated hand touching did not enhance either of these factors compared to visual feedback. Further analysis of the data showed that participants scoring low on Extraversion (i.e., persons that are more introvert) or low on Touch Receptivity (i.e., persons who do not like to be touched by others) felt better understood by their communication partner when receiving mediated touch feedback instead of visual feedback, while the opposite was found for participants scoring high on these factors. The implications of these results for further research are discussed, and some suggestions for follow-up experiments are presented. PMID:26557429

  14. A Serious Game to Improve Cognitive Functions in Schizophrenia: A Pilot Study

    PubMed Central

    Amado, Isabelle; Brénugat-Herné, Lindsay; Orriols, Eric; Desombre, Colombe; Dos Santos, Maxine; Prost, Zelda; Krebs, Marie-Odile; Piolino, Pascale

    2016-01-01

    Cognitive deficits in schizophrenia impair everyday functioning and instrumental daily living activities. These disabilities can be partly responsible for chronicity and institutionalization. We present here a virtual reality (VR) tool in which patients with schizophrenia performed a virtual game in an imaginary town during a 3-month program. In a pilot study, seven patients with schizophrenia (DSM-5), institutionalized for many years, attended weekly 1-h-and-a-half sessions organized by two clinicians. During the first sessions, they listed together the difficulties they experienced in everyday organization and planning. After being familiarized with the joystick and the VR environment, they navigated in the town, and planned actions that were difficult for them to carry out in their usual life (e.g., shopping, memorizing the way to the supermarket or being on time at a meeting point). They had to look for alternative routes and practice a switch from a 2D Map to the 3D Map. They also gathered their efforts to share strategies for each action, or discussed the action plan they could generate to solve concrete problems. The pre/post-neuropsychological evaluations showed attention, working memory, prospective, and retrospective memory benefits, but no improvement in planning as assessed by the Zoo map test and the action program subtest of Behavioral Assessment of the Dysexecutive Syndrome. Patients also clinically and functionally improved, gaining autonomy. Pragmatically, they reported a strong energy to elaborate concrete plans to search for jobs, or return to activities in the community. Qualitative assessments showed a benefit in sparing time, planning better, enriched relatedness, and better management of their housework. This VR game opens avenue to rehabilitation for patients with schizophrenia experiencing chronicity in their life, less attendance in daycare units, and a better community living. This program might reduce neurocognitive difficulties and might evolve into a true method for cognitive remediation (trial n° 2011-A00988-33). PMID:27148093

  15. Feature determination from powered wheelchair user joystick input characteristics for adapting driving assistance

    PubMed Central

    Gillham, Michael; Pepper, Matthew; Kelly, Steve; Howells, Gareth

    2018-01-01

    Background: Many powered wheelchair users find their medical condition and their ability to drive the wheelchair will change over time. In order to maintain their independent mobility, the powered chair will require adjustment over time to suit the user's needs, thus regular input from healthcare professionals is required. These limited resources can result in the user having to wait weeks for appointments, resulting in the user losing independent mobility, consequently affecting their quality of life and that of their family and carers. In order to provide an adaptive assistive driving system, a range of features need to be identified which are suitable for initial system setup and can automatically provide data for re-calibration over the long term. Methods: A questionnaire was designed to collect information from powered wheelchair users with regard to their symptoms and how they changed over time. Another group of volunteer participants were asked to drive a test platform and complete a course which represented manoeuvring in a very confined space as quickly as possible. Two of those participants were also monitored over a longer period in their normal home daily environment. Features, thought to be suitable, were examined using pattern recognition classifiers to determine their suitability for identifying the changing user input over time. Results: The results are not designed to provide absolute insight into the individual user behaviour, as no ground truth of their ability has been determined, they do nevertheless demonstrate the utility of the measured features to provide evidence of the users’ changing ability over time whilst driving a powered wheelchair. Conclusions: Determining the driving features and adjustable elements provides the initial step towards developing an adaptable assistive technology for the user when the ground truths of the individual and their machine have been learned by a smart pattern recognition system. PMID:29552641

  16. Determining Exercise Strength Requirements for Astronaut Critical Mission Tasks: Reaching Under G-Load

    NASA Technical Reports Server (NTRS)

    Schaffner, Grant; Bentley, Jason

    2008-01-01

    The critical mission tasks assessments effort seeks to determine the physical performance requirements that astronauts must meet in order to safely and successfully accomplish lunar exploration missions. These assessments will determine astronaut preflight strength, fitness, and flexibility requirements, and the extent to which exercise and other countermeasures must prevent the physical deconditioning associated with prolonged weightlessness. The purpose is to determine the flexibility and strength that crewmembers must possess in order to reach Crew Exploration Vehicle controls during maneuvers that result in sustained acceleration levels ranging from 3.7G to 7.8G. An industry standard multibody dynamics application was used to create human models representing a 5th percentile female, a 50th percentile male, and a 95th percentile male. The additional mass of a space suit sleeve was added to the reaching arm to account for the influence of the suit mass on the reaching effort. The human model was merged with computer models of a pilot seat and control panel for the Crew Exploration Vehicle. Three dimensional paths were created that guided the human models hand from a starting position alongside its thigh to three control targets: a joystick, a keyboard, and an overhead switch panel. The reaching motion to each target was repeated under four vehicle acceleration conditions: nominal ascent (3.7G), two ascent aborts (5.5G and 7.8G) and lunar reentry (4.6G). Elbow and shoulder joint angular excursions were analyzed to assess range of motion requirements. Mean and peak elbow and shoulder joint torques were determined and converted to equivalent resistive exercise loads to assess strength requirements. Angular excursions for the 50th and 95th percentile male models remained within joint range of motion limits. For the 5th percentile female, both the elbow and the shoulder exceeded range of motion limits during the overhead reach. Elbow joint torques ranged from 10 N-m (nominal ascent) to 60 N-m (ascent abort). Shoulder joint torques ranged from 65 N-m (nominal ascent) to 280 N-m (ascent abort). Maximal equivalent exercise loads reached 30 lb in tricep extension, 9 lb in bicep curl, 110 lb in unilateral pullover and unilateral bench press for nominal conditions (lunar reentry), and 188 lb in unilateral pullover and unilateral bench press. The location of the pilot seat was found to be inadequately located to allow a 5th percentile female to reach the switches on the overhead panel. Elbow strength requirements were found to be well within population norms. Shoulder strength was found to be a limiting factor. Reaching under nominal ascent and lunar reentry conditions was found to require near maximal shoulder strength. Reaching under ascent abort conditions requires shoulder strength well beyond population norms. Pilot seats must adjust to accomodate a 5th percentile female. Exercise countermeasures must maintain maximal pullover and bench press strength to allow pilots to reach and operate controls during lunar reentry. Reaching will not be possible during ascent abort conditions. Flight controls should be built into armrests or flight control must be accomplished by autonomous systems during acceleration exceeding 4.6G.

  17. Modified anterior-only reduction and fixation for traumatic cervical facet dislocation (AO type C injuries).

    PubMed

    Kanna, Rishi M; Shetty, Ajoy P; Rajasekaran, S

    2018-06-01

    Surgical reduction of uni and bi-facetal dislocations of the cervical spine (AO type C injuries) can be performed by posterior, anterior or combined approaches. Ease of access, low infection rates and less risks of neurological worsening has popularized anterior approach. However, the reduction of locked cervical facets can be intricate through anterior approach. We analyzed the safety, efficacy and outcomes at a minimum 1 year, of a novel anterior reduction technique for consecutively treated cervical facet dislocations. Patients with single level traumatic sub-axial cervical dislocation (n = 39) treated by this modified anterior technique were studied. The technique involved standard Smith-Robinson approach, discectomy beyond PLL, use of inter-laminar distracter to distract while Caspar pins were used as "joysticks" (either flexion-extension or lateral rotation moments are provided), to reduce the sub-luxed facets. Among 51 patients with cervical type C injury treated during the study period, 4 patients who had spontaneous reduction and 8 treated by planned global fusion were excluded. 39 patients of mean age 49.9 years were studied. The levels of injury included (C3-4 = 2, C4-5 = 5, C5-6 = 20, C6-7 = 12). 18 were bi-facetal and 21 were uni-facetal dislocation. One facet was fractured in 17 and both in 5 patients. 30% (n = 13) had a concomitant disc prolapse. The neurological status was as follows: 9 ASIA A, 9 ASIA C, 13 ASIA D and 8 ASIA E. All the patients were successfully reduced by this technique and fixed with anterior locking cervical locking plates. No supplemental posterior surgery was performed. 22 patients with incomplete deficit showed recovery. The mean follow-up was 14.3 months and there was no implant failure except one patient who had partial loss of the reduction. Patients with traumatic sub-axial cervical dislocation (AO type C injuries) can be safely and effectively reduced by this technique. Other advantages include minimal blood loss, less risks of infection, shorted fusion zone, good fusion rate and neurological recovery.

  18. "A cigarette a day keeps the goodies away": smokers show automatic approach tendencies for smoking--but not for food-related stimuli.

    PubMed

    Machulska, Alla; Zlomuzica, Armin; Adolph, Dirk; Rinck, Mike; Margraf, Jürgen

    2015-01-01

    Smoking leads to the development of automatic tendencies that promote approach behavior toward smoking-related stimuli which in turn may maintain addictive behavior. The present study examined whether automatic approach tendencies toward smoking-related stimuli can be measured by using an adapted version of the Approach-Avoidance Task (AAT). Given that progression of addictive behavior has been associated with a decreased reactivity of the brain reward system for stimuli signaling natural rewards, we also used the AAT to measure approach behavior toward natural rewarding stimuli in smokers. During the AAT, 92 smokers and 51 non-smokers viewed smoking-related vs. non-smoking-related pictures and pictures of natural rewards (i.e. highly palatable food) vs. neutral pictures. They were instructed to ignore image content and to respond to picture orientation by either pulling or pushing a joystick. Within-group comparisons revealed that smokers showed an automatic approach bias exclusively for smoking-related pictures. Contrary to our expectations, there was no difference in smokers' and non-smokers' approach bias for nicotine-related stimuli, indicating that non-smokers also showed approach tendencies for this picture category. Yet, in contrast to non-smokers, smokers did not show an approach bias for food-related pictures. Moreover, self-reported smoking attitude could not predict approach-avoidance behavior toward nicotine-related pictures in smokers or non-smokers. Our findings indicate that the AAT is suited for measuring smoking-related approach tendencies in smokers. Furthermore, we provide evidence for a diminished approach tendency toward food-related stimuli in smokers, suggesting a decreased sensitivity to natural rewards in the course of nicotine addiction. Our results indicate that in contrast to similar studies conducted in alcohol, cannabis and heroin users, the AAT might only be partially suited for measuring smoking-related approach tendencies in smokers. Nevertheless, our findings are of special importance for current etiological models and smoking cessation programs aimed at modifying nicotine-related approach tendencies in the context of a nicotine addiction.

  19. Human machine interaction via the transfer of power and information signals

    NASA Technical Reports Server (NTRS)

    Kazerooni, H.; Foslien, W. K.; Anderson, B. J.; Hessburg, T. M.

    1989-01-01

    Robot manipulators are designed to perform tasks which would otherwise be executed by a human operator. No manipulator can even approach the speed and accuracy with which humans execute these tasks. But manipulators have the capability to exceed human ability in one particular area: strength. Through any reasonable observation and experience, the human's ability to perform a variety of physical tasks is limited not by his intelligence, but by his physical strength. If, in the appropriate environment, we can more closely integrate the mechanical power of a machine with intellectually driven human hand under the supervisory control of the human's intellect, we will then have a system which is superior to a loosely-integrated combination of a human and his fully automated robot as in the present day robotic systems. We must therefore develop a fundamental approach to the problem of this extending human mechanical power in certain environments. Extenders will be a class of robots worn by humans to increase human mechanical ability, while the wearer's intellect remains the central intelligent control system for manipulating the extender. The human body, in physical contact with the extender, exchanges information signals and power with the extender. Commands are transferred to the extender via the contact forces between the wearer and the extender as opposed to use of joystick (master arm), push-button or key-board to execute such commands that were used in previous man amplifiers. Instead, the operator becomes an integral part of the extender while executing the task. In this unique configuration the mechanical power transfer between the human and extender occurs in addition to information signal transfer. When the wearer uses the extender to touch and manipulate an object, the extender transfers to the wearer's hand, in feedback fashion, a scaled-down value of the actual external load which the extender is manipulating. This natural feedback force on the wearer's hand allows him to feel the scaled-down value of the external forces in the manipulations. Extenders can be utilized to maneuver very heavy loads in factories, shipyards, airports, and construction sites. In some instances, for example, extenders can replace forklifts. The experimental results for a prototype extender are discussed.

  20. A three-fingered, touch-sensitive, metrological micro-robotic assembly tool

    NASA Astrophysics Data System (ADS)

    Torralba, Marta; Hastings, D. J.; Thousand, Jeffery D.; Nowakowski, Bartosz K.; Smith, Stuart T.

    2015-12-01

    This article describes a metrological, robotic hand to manipulate and measure micrometer size objects. The presented work demonstrates not only assembly operations, but also positioning control and metrology capability. Sample motion is achieved by a commercial positioning stage, which provides XYZ-displacements for assembly of components. A designed and manufactured gripper tool that incorporates 21 degrees-of-freedom for independent alignment of actuators, sensors, and the three fingers of this hand is presented. These fingers can be opened and closed by piezoelectric actuators through levered flexures providing an 80 μm displacement range measured with calibrated opto-interrupter based, knife-edge sensors. The operational ends of the fingers comprise of a quartz tuning fork with a 7 μm diameter 3.2 mm long carbon fiber extending from the end of one tuning fork tine. Finger-tip force-sensing is achieved by the monitoring of individual finger resonances typically at around 32 kHz. Experimental results included are focused on probe performance analysis. Pick and place operation using the three fingers is demonstrated with all fingers being continuously oscillated, a capability not possible with the previous single or two finger tweezer type designs. By monitoring electrical feedback during pick and place operations, changes in the response of the three probes demonstrate the ability to identify both grab and release operations. Component metrology has been assessed by contacting different micro-spheres of diameters 50(±7.5) μm, 135(±20) μm, and 140(±20) μm. These were measured by the micro robot to have diameters of 67, 133, and 126 μm respectively with corresponding deviations of 4.2, 4.9, and 4.3 μm. This deviation in the measured results was primarily due to the manual, joystick-based, contacting of the fingers, difficulties associated with centering the components to the axis of the hand, and lower contact sensitivity for the smallest sphere. Finally, assemblies of spheres onto the edge of a razor blade plus assembly of spherical contact probes for micro-meter scale coordinate measurement applications are presented.

  1. “A Cigarette a Day Keeps the Goodies Away”: Smokers Show Automatic Approach Tendencies for Smoking—But Not for Food-Related Stimuli

    PubMed Central

    Adolph, Dirk; Rinck, Mike; Margraf, Jürgen

    2015-01-01

    Smoking leads to the development of automatic tendencies that promote approach behavior toward smoking-related stimuli which in turn may maintain addictive behavior. The present study examined whether automatic approach tendencies toward smoking-related stimuli can be measured by using an adapted version of the Approach-Avoidance Task (AAT). Given that progression of addictive behavior has been associated with a decreased reactivity of the brain reward system for stimuli signaling natural rewards, we also used the AAT to measure approach behavior toward natural rewarding stimuli in smokers. During the AAT, 92 smokers and 51 non-smokers viewed smoking-related vs. non-smoking-related pictures and pictures of natural rewards (i.e. highly palatable food) vs. neutral pictures. They were instructed to ignore image content and to respond to picture orientation by either pulling or pushing a joystick. Within-group comparisons revealed that smokers showed an automatic approach bias exclusively for smoking-related pictures. Contrary to our expectations, there was no difference in smokers’ and non-smokers’ approach bias for nicotine-related stimuli, indicating that non-smokers also showed approach tendencies for this picture category. Yet, in contrast to non-smokers, smokers did not show an approach bias for food-related pictures. Moreover, self-reported smoking attitude could not predict approach-avoidance behavior toward nicotine-related pictures in smokers or non-smokers. Our findings indicate that the AAT is suited for measuring smoking-related approach tendencies in smokers. Furthermore, we provide evidence for a diminished approach tendency toward food-related stimuli in smokers, suggesting a decreased sensitivity to natural rewards in the course of nicotine addiction. Our results indicate that in contrast to similar studies conducted in alcohol, cannabis and heroin users, the AAT might only be partially suited for measuring smoking-related approach tendencies in smokers. Nevertheless, our findings are of special importance for current etiological models and smoking cessation programs aimed at modifying nicotine-related approach tendencies in the context of a nicotine addiction. PMID:25692468

  2. Male sexual dysfunctions: immersive virtual reality and multimedia therapy.

    PubMed

    Optale, Gabriele; Pastore, Massimiliano; Marin, Silvia; Bordin, Diego; Nasta, Alberto; Pianon, Carlo

    2004-01-01

    The study describes a therapeutic approach using psycho-dynamic psychotherapy integrating virtual environment (VE) for resolving impotence or better erectile dysfunction (ED) of presumably psychological or mixed origin and premature ejaculation (PE). The plan for therapy consists of 12 sessions (15 if a sexual partner was involved) over a 25-week period on the ontogenetic development of male sexual identity, and the methods involved the use of a laptop PC, joystick, Virtual Reality (VR) helmet with miniature television screen showing a new specially-designed CD-ROM programs using Virtools with Windows 2000 and an audio CD. This study was composed of 30 patients, 15 (10 suffering from ED and 5 PE) plus 15 control patients (10 ED and 5 PE), that underwent the same therapeutic protocol but used an old VR helmet to interact with the old VE using a PC Pentium 133 16 Mb RAM. We also compared this study with another study we carried out on 160 men affected by sexual disorders, underwent the same therapeutic protocol, but treated using a VE created (in Superscape VRT 5.6) using always Windows 2000 with portable tools. Comparing the groups of patients affected by ED and PE, there emerged a significant positive results value without any important differences among the different VE used. However, we had a % increase of undesirable physical reactions during the more realistic 15-minute VR experience using Virtools development kit. Psychotherapy alone normally requires long periods of treatment in order to resolve sexual dysfunctions. Considering the particular way in which full-immersion VR involves the subject who experiences it (he is totally unobserved and in complete privacy), we hypothesise that this methodological approach might speed up the therapeutic psycho-dynamic process, which eludes cognitive defences and directly stimulates the subconscious, and that better results could be obtained in the treatment of these sexual disorders. This method can be used by any psychotherapist and it can be used alone or associated with pharmacotherapy prescribed by the urologist/andrologist as part of a therapeutic alliance.

  3. Acquisition of Skill Proficiency Over Multiple Sessions of a Novel Rover Simulation

    NASA Technical Reports Server (NTRS)

    Dean, S. L.; DeDios,Y. E.; MacDougall, H. G.; Moore, S. T.; Wood, S. J.

    2011-01-01

    Following long-duration exploration transits, adaptive changes in sensorimotor function may impair the crew's ability to safely perform manual control tasks such as operating pressurized rovers. Postflight performance will also be influenced by the level of preflight skill proficiency they have attained. The purpose of this study was to characterize the acquisition of skills in a motion-based rover simulation over multiple sessions, and to investigate the effects of varying the simulation scenarios. METHODS: Twenty healthy subjects were tested in 5 sessions, with 1-3 days between sessions. Each session consisted of a serial presentation of 8 discrete tasks to be completed as quickly and accurately as possible. Each task consisted of 1) perspective-taking, using a map that defined a docking target, 2) navigation toward the target around a Martian outpost, and 3) docking a side hatch of the rover to a visually guided target. The simulator utilized a Stewart-type motion base (CKAS, Australia), single-seat cabin with triple scene projection covering 150 deg horizontal by 50 deg vertical, and joystick controller. Subjects were randomly assigned to a control group (tasks identical in the first 4 sessions) or a varied-practice group. The dependent variables for each task included accuracy toward the target and time to completion. RESULTS: The greatest improvements in time to completion occurred during the docking phase. The varied-practice group showed more improvement in perspective-taking accuracy. Perspective-taking accuracy was also affected by the relative orientation of the rover to the docking target. Skill acquisition was correlated with self-ratings of previous gaming experience. DISCUSSION: Varying task selection and difficulty will optimize the preflight acquisition of skills when performing novel operational tasks. Simulation of operational manual control will provide functionally relevant evidence regarding the impact of sensorimotor adaptation on early surface operations and what countermeasures are needed. Learning Objective: The use of a motion-based simulation to investigate decrements in the proficiency to operate pressurized rovers during early surface operations of space exploration missions, along with the acquisition of skill proficiency needed during the preflight phase of the mission.

  4. Relationship Between Psychomotor Efficiency and Sensation Seeking of People Exposed to Noise and Low Frequency Vibration Stimuli

    NASA Astrophysics Data System (ADS)

    Korchut, Aleksander; Kowalska-Koczwara, Alicja; Romanska – Zapała, Anna; Stypula, Krzysztof

    2017-10-01

    At the workplace of the machine operator, low frequency whole body and hand- arm vibrations are observed. They occur together with noise. Whole body vibration in the range of 3-25 Hz are detrimental to the human body due to the location of the resonant frequency of large organs of the human body in this range. It can be assumed that for this reason people working every day in such conditions can have reduced working efficiency. The influence of low frequency vibration and noise on the human body leads to both physiological and functional changes. The result of the impact of noise and vibration stimuli depends largely on the specific characteristics of the objects, which include among other personality traits, temperament and emotional factor. The pilot study conducted in the laboratory was attended by 30 young men. The aim of the study was to look for correlations between the need for stimulation of the objects and their psychomotor efficiency in case of vibration exposure and vibration together with noise exposure in variable conditions task. The need for stimulation of the objects as defined in the study is based on theoretical assumptions of one dimensional model of temperament developed by Marvin Zuckerman. This theory defines the need for stimulation as the search for different, new, complex and intense sensations, as well as the willingness to take risks. The aim of research was to verify if from four factors such as: the search for adventure and horror, sensation seeking, disinhibition and susceptibility to boredom, we can choose the ones that in conjunction with varying operating conditions, may significantly determine the efficiency of the task situation. The objects performed the test evaluation of their motor skills which consisted in keeping the cursor controlled by a joystick through the path. The number of exceeds of the cursor beyond the path and its maximum deviation was recorded. The collected data were used to determine the correlation between the working efficiency and the need for stimulation of the objects under the influence of vibroacoustic factors. The analysis of the results allowed to define a set of criteria that make up the arduous working conditions. The obtained results indicate the need for the continuation of the research.

  5. Three dimensional touch and vision for the micro-world

    NASA Astrophysics Data System (ADS)

    Bowman, Richard W.

    This thesis describes advances in the holographic technology used to control multiple optical traps (and hence many trapped particles), and improved methods for monitoring the positions and forces involved. The speed with which multiple holographic optical traps can be moved has traditionally been limited by the time taken to calculate holograms, but by using consumer graphics cards and high speed Spatial Light Modulators (SLMs) I have implemented holographic systems fast enough to react to the Brownian motion of trapped particles. Brownian motion can, to some extent, be suppressed by this approach, and it also allows the trap's stiffness to be engineered to balance sensitivity against tight constraint of position. Feedback control using an SLM, rather than the other beam steering technologies that have been employed, is able to react to motion in three dimensions. This requires 3D position measurement, which is provided by the stereo microscopy technique described in Chapter 2. By illuminating and viewing the sample from two different angles it is possible to reconstruct the depth of objects. This is accomplished through a single high numerical aperture microscope objective, the same lens used to focus the trapping laser. In conjunction with a fast CMOS camera, it is possible to track particles with an accuracy of 2-3nm at several thousand frames per second. This allows measurement of forces and displacements within the control loop, that can be fed back to influence the position of the optical traps. This force information can also be relayed to the operator using a force-feedback joystick as detailed in Chapter 7. Interface design is an important part of making technology accessible to scientists from other disciplines; to this end I have also developed a multi-touch tablet application to control optical tweezers. By creating simple, reliable systems and coupling them to an intuitive interface, I have endeavoured to produce developments which are of use to the non-specialist as well as to experts in optical tweezers-a number of which are now available commercially (Section 8.7). These technologies form the basis of a toolkit for working with multi-part probes in optical tweezers, and they should bear fruit in the coming years as a new form of scanning-probe microscopy emerges.

  6. Haptic subjective vertical shows context dependence: task and vision play a role during dynamic tilt stimulation.

    PubMed

    Wright, William Geoffrey; Glasauer, Stefan

    2003-10-01

    Perceiving one's vertical is an integral part of efficiently functioning in an environment physically polarized along that dimension. How one determines the direction of gravity is not a task left only to inertial sensors, such as the vestibular organs, rather as numerous studies have shown, this task is influenced visually and somatosensorily. In addition, there is evidence that higher order cognitive effects such as expectancies and context are critical in perception of the vertical. One's ability to integrate these various inputs during normal activity is not generally questioned, one's doubts being satisfied by observing a waiter navigating a crowded restaurant with a tray balanced on one hand, neither tripping or dropping an entree. But how these various sources are integrated is still debated. Most research focuses on subjective vertical perception used visual matching/alignment tasks, verbal reports, or saccadic eye movements as a dependent measure. Although a motor task involving a joystick or indicator to be aligned with gravity without visual feedback is used much less frequently, there is good evidence that individuals easily orient limbs to an external gravity-aligned coordinate axis while being statically tilted. By exposure to a dynamic situation, the central nervous system should be no more challenged by the task of determining the subjective vertical than during static conditions, because our spatial orientation systems were likely selected for just that. In addition, the sensitive calibration between visual and other sensory input also must have been key to its selection. This sensory interaction can be tested by changing the relation between the various sources. With the advent of virtual reality technology, a complex and "natural" visual stimulus is achievable and is easily manipulable. How one tests perception of verticality is also a pertinent question when researching spatial orientation systems. The system's performance may be better indicated by a task of higher relevance to its normal function. In other words, the dependent measure can be made more or less relevant to real-world tasks. With an experimental design that attempts to mimic natural conditions, the current study focuses on two main topics. First, how does manipulation of the visual inputs during passive roll-tilt affect one's sense of body orientation? And second, how does changing the task used to measure subjective vertical affect one's performance?

  7. Cortical Oscillatory Mechanisms Supporting the Control of Human Social-Emotional Actions.

    PubMed

    Bramson, Bob; Jensen, Ole; Toni, Ivan; Roelofs, Karin

    2018-06-20

    The human anterior prefrontal cortex (aPFC) is involved in regulating social-emotional behavior, presumably by modulating effective connectivity with downstream parietal, limbic, and motor cortices. Regulating that connectivity might rely on theta-band oscillations (4-8 Hz), a brain rhythm known to create overlapping periods of excitability between distant regions by temporally releasing neurons from inhibition. Here, we used MEG to understand how aPFC theta-band oscillations implement control over prepotent social-emotional behaviors; that is, the control over automatically elicited approach and avoidance actions. Forty human male participants performed a social approach-avoidance task in which they approached or avoided visually displayed emotional faces (happy or angry) by pulling or pushing a joystick. Approaching angry and avoiding happy faces (incongruent condition) requires rapid application of cognitive control to override prepotent habitual action tendencies to approach appetitive and to avoid aversive situations. In the time window before response delivery, trial-by-trial variations in aPFC theta-band power (6 Hz) predicted reaction time increases during emotional control and were inversely related to beta-band power (14-22 Hz) over parietofrontal cortex. In sensorimotor areas contralateral to the moving hand, premovement gamma-band rhythms (60-90 Hz) were stronger during incongruent than congruent trials, with power increases phase locked to peaks of the aPFC theta-band oscillations. These findings define a mechanistic relation between cortical areas involved in implementing rapid control over human social-emotional behavior. The aPFC may bias neural processing toward rule-driven actions and away from automatic emotional tendencies by coordinating tonic disinhibition and phasic enhancement of parietofrontal circuits involved in action selection. SIGNIFICANCE STATEMENT Being able to control social-emotional behavior is crucial for successful participation in society, as is illustrated by the severe social and occupational difficulties experienced by people suffering from social motivational disorders such as social anxiety. In this study, we show that theta-band oscillations in the anterior prefrontal cortex (aPFC), which are thought to provide temporal organization for neural firing during communication between distant brain areas, facilitate this control by linking aPFC to parietofrontal beta-band and sensorimotor gamma-band oscillations involved in action selection. These results contribute to a mechanistic understanding of cognitive control over automatic social-emotional action and point to frontal theta-band oscillations as a possible target of rhythmic neurostimulation techniques during treatment for social anxiety. Copyright © 2018 the authors 0270-6474/18/385739-11$15.00/0.

  8. The role of vestibular and support-tactile-proprioceptive inputs in visual-manual tracking

    NASA Astrophysics Data System (ADS)

    Kornilova, Ludmila; Naumov, Ivan; Glukhikh, Dmitriy; Khabarova, Ekaterina; Pavlova, Aleksandra; Ekimovskiy, Georgiy; Sagalovitch, Viktor; Smirnov, Yuriy; Kozlovskaya, Inesa

    Sensorimotor disorders in weightlessness are caused by changes of functioning of gravity-dependent systems, first of all - vestibular and support. The question arises, what’s the role and the specific contribution of the support afferentation in the development of observed disorders. To determine the role and effects of vestibular, support, tactile and proprioceptive afferentation on characteristics of visual-manual tracking (VMT) we conducted a comparative analysis of the data obtained after prolonged spaceflight and in a model of weightlessness - horizontal “dry” immersion. Altogether we examined 16 Russian cosmonauts before and after prolonged spaceflights (129-215 days) and 30 subjects who stayed in immersion bath for 5-7 days to evaluate the state of the vestibular function (VF) using videooculography and characteristics of the visual-manual tracking (VMT) using electrooculography & joystick with biological visual feedback. Evaluation of the VF has shown that both after immersion and after prolonged spaceflight there were significant decrease of the static torsional otolith-cervical-ocular reflex (OCOR) and simultaneous significant increase of the dynamic vestibular-cervical-ocular reactions (VCOR) with a revealed negative correlation between parameters of the otoliths and canals reactions, as well as significant changes in accuracy of perception of the subjective visual vertical which correlated with changes in OCOR. Analyze of the VMT has shown that significant disorders of the visual tracking (VT) occurred from the beginning of the immersion up to 3-4 day after while in cosmonauts similar but much more pronounced oculomotor disorders and significant changes from the baseline were observed up to R+9 day postflight. Significant changes of the manual tracking (MT) were revealed only for gain and occurred on 1 and 3 days in immersion while after spaceflight such changes were observed up to R+5 day postflight. We found correlation between characteristics of the VT and MT, between characteristics of the VF and VT and no correlation between VF and MT. It was found that removal of the support and minimization of the proprioceptive afferentation has a greater impact upon accuracy of the VT then accuracy of the MT. Hand tracking accuracy was higher than the eyes for all subjects. The hand’ motor coordination was more stable to changes in support-proprioceptive afferentation then visual tracking. The observed changes in and after immersion are similar but less pronounced with changes observed on cosmonauts after prolonged spaceflight. Keywords: visual-manual tracking, vestibular function, weightlessness, immersion.

  9. Telerobotic Excavator Designed to Compete in NASA's Lunabotics Mining Competition

    NASA Technical Reports Server (NTRS)

    Nash, Rodney; Santin, Cara; Yousef, Ahmed; Nguyen, Thien; Helferty, John; Pillapakkam, Shriram

    2011-01-01

    The second annual NASA Lunabotics Mining competition is to be held in May 23-28, 2011. The goal of the competition is for teams of university level students to design, build, test and compete with a fully integrated lunar excavator on a simulated lunar surface. Our team, named Lunar Solutions I, will be representing Temple University's College of Engineering in the competition. The team's main goal was to build a robot which is able to compete with other teams, and ultimately win the competition. The main challenge of the competition was to build a wireless robot that can excavate and collect a minimum of 10 kilograms of the regolith material within 15 minutes. The robot must also be designed to operate in conditions similar to those found on the lunar surface. The design of the lunar excavator is constrained by a set of requirements determined by NASA and detailed in the competition's rulebook. The excavator must have the ability to communicate with the "main base" wirelessly, and over a Wi-Fi network. Human operators are located at a remote site approximately 60 meters away from the simulated lunar surface upon which the robot must excavate the lunar regolith surface. During the competition, the robot will operate in a separate area from the control room in an area referred to as the "Lunarena." From the control room, the operators will have to control the robot using visual feedback from cameras placed both within the arena and on the robot. Using this visual feedback the human operators control the robots movement using both keyboard and joystick commands. In order to place in the competition, a minimum of 10 kg of regolith material has to be excavated, collected, and dumped into a specific location. For that reason, the robot must be provided with an effective and powerful excavation system. Our excavator uses tracks for the drive system. After performing extensive research and trade studies, we concluded that tracks would be the most effective method for transporting the excavator. When designing the excavation system, we analyzed several design options from the previous year's competition. We decided to use a front loader to collect the material, rather than a conveyer belt system or auger. Many of the designs from last year's competition used a conveyer belt mechanism to mine regolith and dump it into a temporary storage bin place on the robot. Using the front end loader approach allowed us to combine the scooping system and storage unit, which meant that the excavation system required less space.

  10. Collectively loading an application in a parallel computer

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Aho, Michael E.; Attinella, John E.; Gooding, Thomas M.

    Collectively loading an application in a parallel computer, the parallel computer comprising a plurality of compute nodes, including: identifying, by a parallel computer control system, a subset of compute nodes in the parallel computer to execute a job; selecting, by the parallel computer control system, one of the subset of compute nodes in the parallel computer as a job leader compute node; retrieving, by the job leader compute node from computer memory, an application for executing the job; and broadcasting, by the job leader to the subset of compute nodes in the parallel computer, the application for executing the job.

  11. Distributing an executable job load file to compute nodes in a parallel computer

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Gooding, Thomas M.

    Distributing an executable job load file to compute nodes in a parallel computer, the parallel computer comprising a plurality of compute nodes, including: determining, by a compute node in the parallel computer, whether the compute node is participating in a job; determining, by the compute node in the parallel computer, whether a descendant compute node is participating in the job; responsive to determining that the compute node is participating in the job or that the descendant compute node is participating in the job, communicating, by the compute node to a parent compute node, an identification of a data communications linkmore » over which the compute node receives data from the parent compute node; constructing a class route for the job, wherein the class route identifies all compute nodes participating in the job; and broadcasting the executable load file for the job along the class route for the job.« less

  12. Organization of the secure distributed computing based on multi-agent system

    NASA Astrophysics Data System (ADS)

    Khovanskov, Sergey; Rumyantsev, Konstantin; Khovanskova, Vera

    2018-04-01

    Nowadays developing methods for distributed computing is received much attention. One of the methods of distributed computing is using of multi-agent systems. The organization of distributed computing based on the conventional network computers can experience security threats performed by computational processes. Authors have developed the unified agent algorithm of control system of computing network nodes operation. Network PCs is used as computing nodes. The proposed multi-agent control system for the implementation of distributed computing allows in a short time to organize using of the processing power of computers any existing network to solve large-task by creating a distributed computing. Agents based on a computer network can: configure a distributed computing system; to distribute the computational load among computers operated agents; perform optimization distributed computing system according to the computing power of computers on the network. The number of computers connected to the network can be increased by connecting computers to the new computer system, which leads to an increase in overall processing power. Adding multi-agent system in the central agent increases the security of distributed computing. This organization of the distributed computing system reduces the problem solving time and increase fault tolerance (vitality) of computing processes in a changing computing environment (dynamic change of the number of computers on the network). Developed a multi-agent system detects cases of falsification of the results of a distributed system, which may lead to wrong decisions. In addition, the system checks and corrects wrong results.

  13. Aggregating job exit statuses of a plurality of compute nodes executing a parallel application

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Aho, Michael E.; Attinella, John E.; Gooding, Thomas M.

    Aggregating job exit statuses of a plurality of compute nodes executing a parallel application, including: identifying a subset of compute nodes in the parallel computer to execute the parallel application; selecting one compute node in the subset of compute nodes in the parallel computer as a job leader compute node; initiating execution of the parallel application on the subset of compute nodes; receiving an exit status from each compute node in the subset of compute nodes, where the exit status for each compute node includes information describing execution of some portion of the parallel application by the compute node; aggregatingmore » each exit status from each compute node in the subset of compute nodes; and sending an aggregated exit status for the subset of compute nodes in the parallel computer.« less

  14. DOE Office of Scientific and Technical Information (OSTI.GOV)

    Gooding, Thomas M.

    Distributing an executable job load file to compute nodes in a parallel computer, the parallel computer comprising a plurality of compute nodes, including: determining, by a compute node in the parallel computer, whether the compute node is participating in a job; determining, by the compute node in the parallel computer, whether a descendant compute node is participating in the job; responsive to determining that the compute node is participating in the job or that the descendant compute node is participating in the job, communicating, by the compute node to a parent compute node, an identification of a data communications linkmore » over which the compute node receives data from the parent compute node; constructing a class route for the job, wherein the class route identifies all compute nodes participating in the job; and broadcasting the executable load file for the job along the class route for the job.« less

  15. Neural Computation and the Computational Theory of Cognition

    ERIC Educational Resources Information Center

    Piccinini, Gualtiero; Bahar, Sonya

    2013-01-01

    We begin by distinguishing computationalism from a number of other theses that are sometimes conflated with it. We also distinguish between several important kinds of computation: computation in a generic sense, digital computation, and analog computation. Then, we defend a weak version of computationalism--neural processes are computations in the…

  16. Investigation of the computer experiences and attitudes of pre-service mathematics teachers: new evidence from Turkey.

    PubMed

    Birgin, Osman; Catlioğlu, Hakan; Gürbüz, Ramazan; Aydin, Serhat

    2010-10-01

    This study aimed to investigate the experiences of pre-service mathematics (PSM) teachers with computers and their attitudes toward them. The Computer Attitude Scale, Computer Competency Survey, and Computer Use Information Form were administered to 180 Turkish PSM teachers. Results revealed that most PSM teachers used computers at home and at Internet cafes, and that their competency was generally intermediate and upper level. The study concludes that PSM teachers' attitudes about computers differ according to their years of study, computer ownership, level of computer competency, frequency of computer use, computer experience, and whether they had attended a computer-aided instruction course. However, computer attitudes were not affected by gender.

  17. Computer Fear and Anxiety in the United States Army

    DTIC Science & Technology

    1991-03-01

    number) FIELD I GROUP SUBGROUP Computer Fear, Computer Anxiety, Computerphobia, Cyberphobia, Technostress , Computer Aversion, Corn puterphrenia 19...physiological and psychological disorders that impact not only on individuals, but on organizations as well. " Technostress " is a related term which is...computers, technostress , computer anxious, computer resistance, terminal phobia, fear of technology, computer distrust, and computer aversion. Whatever

  18. Cloud@Home: A New Enhanced Computing Paradigm

    NASA Astrophysics Data System (ADS)

    Distefano, Salvatore; Cunsolo, Vincenzo D.; Puliafito, Antonio; Scarpa, Marco

    Cloud computing is a distributed computing paradigm that mixes aspects of Grid computing, ("… hardware and software infrastructure that provides dependable, consistent, pervasive, and inexpensive access to high-end computational capabilities" (Foster, 2002)) Internet Computing ("…a computing platform geographically distributed across the Internet" (Milenkovic et al., 2003)), Utility computing ("a collection of technologies and business practices that enables computing to be delivered seamlessly and reliably across multiple computers, ... available as needed and billed according to usage, much like water and electricity are today" (Ross & Westerman, 2004)) Autonomic computing ("computing systems that can manage themselves given high-level objectives from administrators" (Kephart & Chess, 2003)), Edge computing ("… provides a generic template facility for any type of application to spread its execution across a dedicated grid, balancing the load …" Davis, Parikh, & Weihl, 2004) and Green computing (a new frontier of Ethical computing1 starting from the assumption that in next future energy costs will be related to the environment pollution).

  19. Paper-Based and Computer-Based Concept Mappings: The Effects on Computer Achievement, Computer Anxiety and Computer Attitude

    ERIC Educational Resources Information Center

    Erdogan, Yavuz

    2009-01-01

    The purpose of this paper is to compare the effects of paper-based and computer-based concept mappings on computer hardware achievement, computer anxiety and computer attitude of the eight grade secondary school students. The students were randomly allocated to three groups and were given instruction on computer hardware. The teaching methods used…

  20. When does a physical system compute?

    PubMed

    Horsman, Clare; Stepney, Susan; Wagner, Rob C; Kendon, Viv

    2014-09-08

    Computing is a high-level process of a physical system. Recent interest in non-standard computing systems, including quantum and biological computers, has brought this physical basis of computing to the forefront. There has been, however, no consensus on how to tell if a given physical system is acting as a computer or not; leading to confusion over novel computational devices, and even claims that every physical event is a computation. In this paper, we introduce a formal framework that can be used to determine whether a physical system is performing a computation. We demonstrate how the abstract computational level interacts with the physical device level, in comparison with the use of mathematical models in experimental science. This powerful formulation allows a precise description of experiments, technology, computation and simulation, giving our central conclusion: physical computing is the use of a physical system to predict the outcome of an abstract evolution . We give conditions for computing, illustrated using a range of non-standard computing scenarios. The framework also covers broader computing contexts, where there is no obvious human computer user. We introduce the notion of a 'computational entity', and its critical role in defining when computing is taking place in physical systems.

  1. When does a physical system compute?

    PubMed Central

    Horsman, Clare; Stepney, Susan; Wagner, Rob C.; Kendon, Viv

    2014-01-01

    Computing is a high-level process of a physical system. Recent interest in non-standard computing systems, including quantum and biological computers, has brought this physical basis of computing to the forefront. There has been, however, no consensus on how to tell if a given physical system is acting as a computer or not; leading to confusion over novel computational devices, and even claims that every physical event is a computation. In this paper, we introduce a formal framework that can be used to determine whether a physical system is performing a computation. We demonstrate how the abstract computational level interacts with the physical device level, in comparison with the use of mathematical models in experimental science. This powerful formulation allows a precise description of experiments, technology, computation and simulation, giving our central conclusion: physical computing is the use of a physical system to predict the outcome of an abstract evolution. We give conditions for computing, illustrated using a range of non-standard computing scenarios. The framework also covers broader computing contexts, where there is no obvious human computer user. We introduce the notion of a ‘computational entity’, and its critical role in defining when computing is taking place in physical systems. PMID:25197245

  2. 48 CFR 227.7203-15 - Subcontractor rights in computer software or computer software documentation.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... computer software or computer software documentation. 227.7203-15 Section 227.7203-15 Federal Acquisition... REQUIREMENTS PATENTS, DATA, AND COPYRIGHTS Rights in Computer Software and Computer Software Documentation 227.7203-15 Subcontractor rights in computer software or computer software documentation. (a...

  3. 48 CFR 227.7203-15 - Subcontractor rights in computer software or computer software documentation.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... computer software or computer software documentation. 227.7203-15 Section 227.7203-15 Federal Acquisition... REQUIREMENTS PATENTS, DATA, AND COPYRIGHTS Rights in Computer Software and Computer Software Documentation 227.7203-15 Subcontractor rights in computer software or computer software documentation. (a...

  4. 48 CFR 227.7203-15 - Subcontractor rights in computer software or computer software documentation.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... computer software or computer software documentation. 227.7203-15 Section 227.7203-15 Federal Acquisition... REQUIREMENTS PATENTS, DATA, AND COPYRIGHTS Rights in Computer Software and Computer Software Documentation 227.7203-15 Subcontractor rights in computer software or computer software documentation. (a...

  5. 48 CFR 227.7203-15 - Subcontractor rights in computer software or computer software documentation.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... computer software or computer software documentation. 227.7203-15 Section 227.7203-15 Federal Acquisition... REQUIREMENTS PATENTS, DATA, AND COPYRIGHTS Rights in Computer Software and Computer Software Documentation 227.7203-15 Subcontractor rights in computer software or computer software documentation. (a...

  6. 48 CFR 227.7203-15 - Subcontractor rights in computer software or computer software documentation.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... computer software or computer software documentation. 227.7203-15 Section 227.7203-15 Federal Acquisition... REQUIREMENTS PATENTS, DATA, AND COPYRIGHTS Rights in Computer Software and Computer Software Documentation 227.7203-15 Subcontractor rights in computer software or computer software documentation. (a...

  7. 77 FR 26041 - Certain Computers and Computer Peripheral Devices and Components Thereof and Products Containing...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-05-02

    ... INTERNATIONAL TRADE COMMISSION [Inv. No. 337-TA-841] Certain Computers and Computer Peripheral... after importation of certain computers and computer peripheral devices and components thereof and... computers and computer peripheral devices and components thereof and products containing the same that...

  8. 48 CFR 227.7202-3 - Rights in commercial computer software or commercial computer software documentation.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... computer software or commercial computer software documentation. 227.7202-3 Section 227.7202-3 Federal... CONTRACTING REQUIREMENTS PATENTS, DATA, AND COPYRIGHTS Rights in Computer Software and Computer Software Documentation 227.7202-3 Rights in commercial computer software or commercial computer software documentation...

  9. 48 CFR 227.7202-3 - Rights in commercial computer software or commercial computer software documentation.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... computer software or commercial computer software documentation. 227.7202-3 Section 227.7202-3 Federal... CONTRACTING REQUIREMENTS PATENTS, DATA, AND COPYRIGHTS Rights in Computer Software and Computer Software Documentation 227.7202-3 Rights in commercial computer software or commercial computer software documentation...

  10. 48 CFR 227.7203-2 - Acquisition of noncommercial computer software and computer software documentation.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... noncommercial computer software and computer software documentation. 227.7203-2 Section 227.7203-2 Federal... CONTRACTING REQUIREMENTS PATENTS, DATA, AND COPYRIGHTS Rights in Computer Software and Computer Software Documentation 227.7203-2 Acquisition of noncommercial computer software and computer software documentation. (a...

  11. 48 CFR 227.7203-2 - Acquisition of noncommercial computer software and computer software documentation.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... noncommercial computer software and computer software documentation. 227.7203-2 Section 227.7203-2 Federal... CONTRACTING REQUIREMENTS PATENTS, DATA, AND COPYRIGHTS Rights in Computer Software and Computer Software Documentation 227.7203-2 Acquisition of noncommercial computer software and computer software documentation. (a...

  12. 48 CFR 227.7203-2 - Acquisition of noncommercial computer software and computer software documentation.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... noncommercial computer software and computer software documentation. 227.7203-2 Section 227.7203-2 Federal... CONTRACTING REQUIREMENTS PATENTS, DATA, AND COPYRIGHTS Rights in Computer Software and Computer Software Documentation 227.7203-2 Acquisition of noncommercial computer software and computer software documentation. (a...

  13. 48 CFR 227.7203-10 - Contractor identification and marking of computer software or computer software documentation to...

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... and marking of computer software or computer software documentation to be furnished with restrictive... Rights in Computer Software and Computer Software Documentation 227.7203-10 Contractor identification and marking of computer software or computer software documentation to be furnished with restrictive markings...

  14. 48 CFR 227.7203-2 - Acquisition of noncommercial computer software and computer software documentation.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... noncommercial computer software and computer software documentation. 227.7203-2 Section 227.7203-2 Federal... CONTRACTING REQUIREMENTS PATENTS, DATA, AND COPYRIGHTS Rights in Computer Software and Computer Software Documentation 227.7203-2 Acquisition of noncommercial computer software and computer software documentation. (a...

  15. 48 CFR 227.7202-3 - Rights in commercial computer software or commercial computer software documentation.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... computer software or commercial computer software documentation. 227.7202-3 Section 227.7202-3 Federal... CONTRACTING REQUIREMENTS PATENTS, DATA, AND COPYRIGHTS Rights in Computer Software and Computer Software Documentation 227.7202-3 Rights in commercial computer software or commercial computer software documentation...

  16. 48 CFR 227.7203-14 - Conformity, acceptance, and warranty of computer software and computer software documentation.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ..., and warranty of computer software and computer software documentation. 227.7203-14 Section 227.7203-14... GENERAL CONTRACTING REQUIREMENTS PATENTS, DATA, AND COPYRIGHTS Rights in Computer Software and Computer Software Documentation 227.7203-14 Conformity, acceptance, and warranty of computer software and computer...

  17. 48 CFR 227.7203-10 - Contractor identification and marking of computer software or computer software documentation to...

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... and marking of computer software or computer software documentation to be furnished with restrictive... Rights in Computer Software and Computer Software Documentation 227.7203-10 Contractor identification and marking of computer software or computer software documentation to be furnished with restrictive markings...

  18. 48 CFR 227.7202-3 - Rights in commercial computer software or commercial computer software documentation.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... computer software or commercial computer software documentation. 227.7202-3 Section 227.7202-3 Federal... CONTRACTING REQUIREMENTS PATENTS, DATA, AND COPYRIGHTS Rights in Computer Software and Computer Software Documentation 227.7202-3 Rights in commercial computer software or commercial computer software documentation...

  19. 48 CFR 227.7203-10 - Contractor identification and marking of computer software or computer software documentation to...

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... and marking of computer software or computer software documentation to be furnished with restrictive... Rights in Computer Software and Computer Software Documentation 227.7203-10 Contractor identification and marking of computer software or computer software documentation to be furnished with restrictive markings...

  20. 48 CFR 227.7203-14 - Conformity, acceptance, and warranty of computer software and computer software documentation.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ..., and warranty of computer software and computer software documentation. 227.7203-14 Section 227.7203-14... GENERAL CONTRACTING REQUIREMENTS PATENTS, DATA, AND COPYRIGHTS Rights in Computer Software and Computer Software Documentation 227.7203-14 Conformity, acceptance, and warranty of computer software and computer...

  1. 48 CFR 227.7202-3 - Rights in commercial computer software or commercial computer software documentation.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... computer software or commercial computer software documentation. 227.7202-3 Section 227.7202-3 Federal... CONTRACTING REQUIREMENTS PATENTS, DATA, AND COPYRIGHTS Rights in Computer Software and Computer Software Documentation 227.7202-3 Rights in commercial computer software or commercial computer software documentation...

  2. 48 CFR 227.7203-14 - Conformity, acceptance, and warranty of computer software and computer software documentation.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ..., and warranty of computer software and computer software documentation. 227.7203-14 Section 227.7203-14... GENERAL CONTRACTING REQUIREMENTS PATENTS, DATA, AND COPYRIGHTS Rights in Computer Software and Computer Software Documentation 227.7203-14 Conformity, acceptance, and warranty of computer software and computer...

  3. 48 CFR 227.7203-10 - Contractor identification and marking of computer software or computer software documentation to...

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... and marking of computer software or computer software documentation to be furnished with restrictive... Rights in Computer Software and Computer Software Documentation 227.7203-10 Contractor identification and marking of computer software or computer software documentation to be furnished with restrictive markings...

  4. 48 CFR 227.7203-14 - Conformity, acceptance, and warranty of computer software and computer software documentation.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ..., and warranty of computer software and computer software documentation. 227.7203-14 Section 227.7203-14... GENERAL CONTRACTING REQUIREMENTS PATENTS, DATA, AND COPYRIGHTS Rights in Computer Software and Computer Software Documentation 227.7203-14 Conformity, acceptance, and warranty of computer software and computer...

  5. 48 CFR 227.7203-14 - Conformity, acceptance, and warranty of computer software and computer software documentation.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ..., and warranty of computer software and computer software documentation. 227.7203-14 Section 227.7203-14... GENERAL CONTRACTING REQUIREMENTS PATENTS, DATA, AND COPYRIGHTS Rights in Computer Software and Computer Software Documentation 227.7203-14 Conformity, acceptance, and warranty of computer software and computer...

  6. 48 CFR 227.7203-10 - Contractor identification and marking of computer software or computer software documentation to...

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... and marking of computer software or computer software documentation to be furnished with restrictive... Rights in Computer Software and Computer Software Documentation 227.7203-10 Contractor identification and marking of computer software or computer software documentation to be furnished with restrictive markings...

  7. 48 CFR 227.7203-2 - Acquisition of noncommercial computer software and computer software documentation.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... noncommercial computer software and computer software documentation. 227.7203-2 Section 227.7203-2 Federal... CONTRACTING REQUIREMENTS PATENTS, DATA, AND COPYRIGHTS Rights in Computer Software and Computer Software Documentation 227.7203-2 Acquisition of noncommercial computer software and computer software documentation. (a...

  8. The Research of the Parallel Computing Development from the Angle of Cloud Computing

    NASA Astrophysics Data System (ADS)

    Peng, Zhensheng; Gong, Qingge; Duan, Yanyu; Wang, Yun

    2017-10-01

    Cloud computing is the development of parallel computing, distributed computing and grid computing. The development of cloud computing makes parallel computing come into people’s lives. Firstly, this paper expounds the concept of cloud computing and introduces two several traditional parallel programming model. Secondly, it analyzes and studies the principles, advantages and disadvantages of OpenMP, MPI and Map Reduce respectively. Finally, it takes MPI, OpenMP models compared to Map Reduce from the angle of cloud computing. The results of this paper are intended to provide a reference for the development of parallel computing.

  9. Providing full point-to-point communications among compute nodes of an operational group in a global combining network of a parallel computer

    DOEpatents

    Archer, Charles J; Faraj, Ahmad A; Inglett, Todd A; Ratterman, Joseph D

    2013-04-16

    Methods, apparatus, and products are disclosed for providing full point-to-point communications among compute nodes of an operational group in a global combining network of a parallel computer, each compute node connected to each adjacent compute node in the global combining network through a link, that include: receiving a network packet in a compute node, the network packet specifying a destination compute node; selecting, in dependence upon the destination compute node, at least one of the links for the compute node along which to forward the network packet toward the destination compute node; and forwarding the network packet along the selected link to the adjacent compute node connected to the compute node through the selected link.

  10. Computer Anxiety: How to Measure It?

    ERIC Educational Resources Information Center

    McPherson, Bill

    1997-01-01

    Provides an overview of five scales that are used to measure computer anxiety: Computer Anxiety Index, Computer Anxiety Scale, Computer Attitude Scale, Attitudes toward Computers, and Blombert-Erickson-Lowrey Computer Attitude Task. Includes background information and scale specifics. (JOW)

  11. The roles of 'subjective computer training' and management support in the use of computers in community health centres.

    PubMed

    Yaghmaie, Farideh; Jayasuriya, Rohan

    2004-01-01

    There have been many changes made to information systems in the last decade. Changes in information systems require users constantly to update their computer knowledge and skills. Computer training is a critical issue for any user because it offers them considerable new skills. The purpose of this study was to measure the effects of 'subjective computer training' and management support on attitudes to computers, computer anxiety and subjective norms to use computers. The data were collected from community health centre staff. The results of the study showed that health staff trained in computer use had more favourable attitudes to computers, less computer anxiety and more awareness of others' expectations about computer use than untrained users. However, there was no relationship between management support and computer attitude, computer anxiety or subjective norms. Lack of computer training for the majority of healthcare staff confirmed the need for more attention to this issue, particularly in health centres.

  12. 48 CFR 227.7203-8 - Deferred delivery and deferred ordering of computer software and computer software documentation.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... deferred ordering of computer software and computer software documentation. 227.7203-8 Section 227.7203-8... GENERAL CONTRACTING REQUIREMENTS PATENTS, DATA, AND COPYRIGHTS Rights in Computer Software and Computer Software Documentation 227.7203-8 Deferred delivery and deferred ordering of computer software and computer...

  13. 48 CFR 227.7203-3 - Early identification of computer software or computer software documentation to be furnished to...

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... computer software or computer software documentation to be furnished to the Government with restrictions on..., DATA, AND COPYRIGHTS Rights in Computer Software and Computer Software Documentation 227.7203-3 Early identification of computer software or computer software documentation to be furnished to the Government with...

  14. 48 CFR 227.7203-8 - Deferred delivery and deferred ordering of computer software and computer software documentation.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... deferred ordering of computer software and computer software documentation. 227.7203-8 Section 227.7203-8... GENERAL CONTRACTING REQUIREMENTS PATENTS, DATA, AND COPYRIGHTS Rights in Computer Software and Computer Software Documentation 227.7203-8 Deferred delivery and deferred ordering of computer software and computer...

  15. 48 CFR 227.7203-3 - Early identification of computer software or computer software documentation to be furnished to...

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... computer software or computer software documentation to be furnished to the Government with restrictions on..., DATA, AND COPYRIGHTS Rights in Computer Software and Computer Software Documentation 227.7203-3 Early identification of computer software or computer software documentation to be furnished to the Government with...

  16. 48 CFR 227.7203-3 - Early identification of computer software or computer software documentation to be furnished to...

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... computer software or computer software documentation to be furnished to the Government with restrictions on..., DATA, AND COPYRIGHTS Rights in Computer Software and Computer Software Documentation 227.7203-3 Early identification of computer software or computer software documentation to be furnished to the Government with...

  17. 48 CFR 227.7203-8 - Deferred delivery and deferred ordering of computer software and computer software documentation.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... deferred ordering of computer software and computer software documentation. 227.7203-8 Section 227.7203-8... GENERAL CONTRACTING REQUIREMENTS PATENTS, DATA, AND COPYRIGHTS Rights in Computer Software and Computer Software Documentation 227.7203-8 Deferred delivery and deferred ordering of computer software and computer...

  18. 48 CFR 227.7203-8 - Deferred delivery and deferred ordering of computer software and computer software documentation.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... deferred ordering of computer software and computer software documentation. 227.7203-8 Section 227.7203-8... GENERAL CONTRACTING REQUIREMENTS PATENTS, DATA, AND COPYRIGHTS Rights in Computer Software and Computer Software Documentation 227.7203-8 Deferred delivery and deferred ordering of computer software and computer...

  19. 48 CFR 227.7203-8 - Deferred delivery and deferred ordering of computer software and computer software documentation.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... deferred ordering of computer software and computer software documentation. 227.7203-8 Section 227.7203-8... GENERAL CONTRACTING REQUIREMENTS PATENTS, DATA, AND COPYRIGHTS Rights in Computer Software and Computer Software Documentation 227.7203-8 Deferred delivery and deferred ordering of computer software and computer...

  20. 48 CFR 227.7203-3 - Early identification of computer software or computer software documentation to be furnished to...

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... computer software or computer software documentation to be furnished to the Government with restrictions on..., DATA, AND COPYRIGHTS Rights in Computer Software and Computer Software Documentation 227.7203-3 Early identification of computer software or computer software documentation to be furnished to the Government with...

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