Applicability Of The Law Of Requisite Variety In Major Military System Acquisition

DTIC Science & Technology

2017-06-01

Iraq. As the insurgency adapted to American tactics, the high mobility multipurpose wheeled vehicle (HMMWV) became a target of the insurgency because...tactics, the high mobility multipurpose wheeled vehicle (HMMWV) became a target of the insurgency because of its lack of armor, which led to significant... high mobility multipurpose wheeled vehicle ICD initial capabilities document IED improvised explosive device IOC initial operating capability JCB

The Design and Development of an Omni-Directional Mobile Robot Oriented to an Intelligent Manufacturing System

PubMed Central

Qian, Jun; Zi, Bin; Ma, Yangang; Zhang, Dan

2017-01-01

In order to transport materials flexibly and smoothly in a tight plant environment, an omni-directional mobile robot based on four Mecanum wheels was designed. The mechanical system of the mobile robot is made up of three separable layers so as to simplify its combination and reorganization. Each modularized wheel was installed on a vertical suspension mechanism, which ensures the moving stability and keeps the distances of four wheels invariable. The control system consists of two-level controllers that implement motion control and multi-sensor data processing, respectively. In order to make the mobile robot navigate in an unknown semi-structured indoor environment, the data from a Kinect visual sensor and four wheel encoders were fused to localize the mobile robot using an extended Kalman filter with specific processing. Finally, the mobile robot was integrated in an intelligent manufacturing system for material conveying. Experimental results show that the omni-directional mobile robot can move stably and autonomously in an indoor environment and in industrial fields. PMID:28891964

The Design and Development of an Omni-Directional Mobile Robot Oriented to an Intelligent Manufacturing System.

PubMed

Qian, Jun; Zi, Bin; Wang, Daoming; Ma, Yangang; Zhang, Dan

2017-09-10

In order to transport materials flexibly and smoothly in a tight plant environment, an omni-directional mobile robot based on four Mecanum wheels was designed. The mechanical system of the mobile robot is made up of three separable layers so as to simplify its combination and reorganization. Each modularized wheel was installed on a vertical suspension mechanism, which ensures the moving stability and keeps the distances of four wheels invariable. The control system consists of two-level controllers that implement motion control and multi-sensor data processing, respectively. In order to make the mobile robot navigate in an unknown semi-structured indoor environment, the data from a Kinect visual sensor and four wheel encoders were fused to localize the mobile robot using an extended Kalman filter with specific processing. Finally, the mobile robot was integrated in an intelligent manufacturing system for material conveying. Experimental results show that the omni-directional mobile robot can move stably and autonomously in an indoor environment and in industrial fields.

Effect of wheelchair design on wheeled mobility and propulsion efficiency in less-resourced settings

PubMed Central

2017-01-01

Background Wheelchair research includes both qualitative and quantitative approaches, primarily focuses on functionality and skill performance and is often limited to short testing periods. This is the first study to use the combination of a performance test (i.e. wheelchair propulsion test) and a multiple-day mobility assessment to evaluate wheelchair designs in rural areas of a developing country. Objectives Test the feasibility of using wheel-mounted accelerometers to document bouts of wheeled mobility data in rural settings and use these data to compare how patients respond to different wheelchair designs. Methods A quasi-experimental, pre- and post-test design was used to test the differences between locally manufactured wheelchairs (push rim and tricycle) and an imported intervention product (dual-lever propulsion wheelchair). A one-way repeated measures analysis of variance was used to interpret propulsion and wheeled mobility data. Results There were no statistical differences in bouts of mobility between the locally manufactured and intervention product, which was explained by high amounts of variability within the data. With regard to the propulsion test, push rim users were significantly more efficient when using the intervention product compared with tricycle users. Conclusion Use of wheel-mounted accelerometers as a means to test user mobility proved to be a feasible methodology in rural settings. Variability in wheeled mobility data could be decreased with longer acclimatisation periods. The data suggest that push rim users experience an easier transition to a dual-lever propulsion system. PMID:28936416

Effect of wheelchair design on wheeled mobility and propulsion efficiency in less-resourced settings.

PubMed

Stanfill, Christopher J; Jensen, Jody L

2017-01-01

Wheelchair research includes both qualitative and quantitative approaches, primarily focuses on functionality and skill performance and is often limited to short testing periods. This is the first study to use the combination of a performance test (i.e. wheelchair propulsion test) and a multiple-day mobility assessment to evaluate wheelchair designs in rural areas of a developing country. Test the feasibility of using wheel-mounted accelerometers to document bouts of wheeled mobility data in rural settings and use these data to compare how patients respond to different wheelchair designs. A quasi-experimental, pre- and post-test design was used to test the differences between locally manufactured wheelchairs (push rim and tricycle) and an imported intervention product (dual-lever propulsion wheelchair). A one-way repeated measures analysis of variance was used to interpret propulsion and wheeled mobility data. There were no statistical differences in bouts of mobility between the locally manufactured and intervention product, which was explained by high amounts of variability within the data. With regard to the propulsion test, push rim users were significantly more efficient when using the intervention product compared with tricycle users. Use of wheel-mounted accelerometers as a means to test user mobility proved to be a feasible methodology in rural settings. Variability in wheeled mobility data could be decreased with longer acclimatisation periods. The data suggest that push rim users experience an easier transition to a dual-lever propulsion system.

A Null Space Control of Two Wheels Driven Mobile Manipulator Using Passivity Theory

NASA Astrophysics Data System (ADS)

Shibata, Tsuyoshi; Murakami, Toshiyuki

This paper describes a control strategy of null space motion of a two wheels driven mobile manipulator. Recently, robot is utilized in various industrial fields and it is preferable for the robot manipulator to have multiple degrees of freedom motion. Several studies of kinematics for null space motion have been proposed. However stability analysis of null space motion is not enough. Furthermore, these approaches apply to stable systems, but they do not apply unstable systems. Then, in this research, base of manipulator equips with two wheels driven mobile robot. This robot is called two wheels driven mobile manipulator, which becomes unstable system. In the proposed approach, a control design of null space uses passivity based stabilizing. A proposed controller is decided so that closed-loop system of robot dynamics satisfies passivity. This is passivity based control. Then, control strategy is that stabilizing of the robot system applies to work space observer based approach and null space control while keeping end-effector position. The validity of the proposed approach is verified by simulations and experiments of two wheels driven mobile manipulator.

Origami Wheel Transformer: A Variable-Diameter Wheel Drive Robot Using an Origami Structure.

PubMed

Lee, Dae-Young; Kim, Sa-Reum; Kim, Ji-Suk; Park, Jae-Jun; Cho, Kyu-Jin

2017-06-01

A wheel drive mechanism is simple, stable, and efficient, but its mobility in unstructured terrain is seriously limited. Using a deformable wheel is one of the ways to increase the mobility of a wheel drive robot. By changing the radius of its wheels, the robot becomes able to pass over not only high steps but also narrow gaps. In this article, we propose a novel design for a variable-diameter wheel using an origami-based soft robotics design approach. By simply folding a patterned sheet into a wheel shape, a variable-diameter wheel was built without requiring lots of mechanical parts and a complex assembly process. The wheel's diameter can change from 30 to 68 mm, and it is light in weight at about 9.7 g. Although composed of soft materials (fabrics and films), the wheel can bear more than 400 times its weight. The robot was able to change the wheel's radius in response to terrain conditions, allowing it to pass over a 50-mm gap when the wheel is shrunk and a 50-mm step when the wheel is enlarged.

Mechanical Design and Testing of an Instrumented Rocker-Bogie Mobility System for the Kapvik Micro-Rover

NASA Astrophysics Data System (ADS)

Setterfield, T.

The rocker-bogie mobility system is a six-wheeled mobility system with the ability to equilibrate ground pressure amongst its wheels and traverse obstacles up to one wheel diameter in height; it has been used previously on NASA's Sojourner, Spirit, Opportunity and Curiosity rovers. This paper presents the mechanical design of an instrumented rocker-bogie mobility system for Kapvik, a 30 kg planetary micro-rover prototype developed for the Canadian Space Agency. The design of the wheel drive system is presented, including: motor selection, gear train selection, and performance limits. The design of a differential mechanism, which minimizes the pitch angle of the rover body, is provided. Design considerations for the integration of single-axis force sensors above the wheel hubs are presented. Structural analysis of the rocker and bogie links is outlined. The cross-hill and uphill-downhill static stability of Kapvik is investigated. Load cell and joint position data from testing during obstacle negotiation and uphill operation are presented.

Hopper on wheels: evolving the hopping robot concept

NASA Technical Reports Server (NTRS)

Schell, S.; Tretten, A.; Burdick, J.; Fuller, S. B.; Fiorini, P.

2001-01-01

This paper describes the evolution of our concept of hopping robot for planetary exploration, that combines coarse long range mobility achieved by hopping, with short range wheeled mobility for precision target acquisition.

Coordinated Control of Slip Ratio for Wheeled Mobile Robots Climbing Loose Sloped Terrain

PubMed Central

Li, Zhengcai; Wang, Yang

2014-01-01

A challenging problem faced by wheeled mobile robots (WMRs) such as planetary rovers traversing loose sloped terrain is the inevitable longitudinal slip suffered by the wheels, which often leads to their deviation from the predetermined trajectory, reduced drive efficiency, and possible failures. This study investigates this problem using terramechanics analysis of the wheel-soil interaction. First, a slope-based wheel-soil interaction terramechanics model is built, and an online slip coordinated algorithm is designed based on the goal of optimal drive efficiency. An equation of state is established using the coordinated slip as the desired input and the actual slip as a state variable. To improve the robustness and adaptability of the control system, an adaptive neural network is designed. Analytical results and those of a simulation using Vortex demonstrate the significantly improved mobile performance of the WMR using the proposed control system. PMID:25276849

Coordinated control of slip ratio for wheeled mobile robots climbing loose sloped terrain.

PubMed

Li, Zhengcai; Wang, Yang

2014-01-01

A challenging problem faced by wheeled mobile robots (WMRs) such as planetary rovers traversing loose sloped terrain is the inevitable longitudinal slip suffered by the wheels, which often leads to their deviation from the predetermined trajectory, reduced drive efficiency, and possible failures. This study investigates this problem using terramechanics analysis of the wheel-soil interaction. First, a slope-based wheel-soil interaction terramechanics model is built, and an online slip coordinated algorithm is designed based on the goal of optimal drive efficiency. An equation of state is established using the coordinated slip as the desired input and the actual slip as a state variable. To improve the robustness and adaptability of the control system, an adaptive neural network is designed. Analytical results and those of a simulation using Vortex demonstrate the significantly improved mobile performance of the WMR using the proposed control system.

A Study on Wheel Sinkage and Rolling Resistance with variations in wheel geometry for Plain and Lugged wheels on TRI -1 Soil Simulant

NASA Astrophysics Data System (ADS)

Gireesh Kumar, Pala; Jayalekshmi, S.

2018-03-01

Wheel-soil Interaction studies are gaining momentum in the field of Terramechanics, but the basis is Terzaghi’s bearing capacity equation. For the current study, on a lunar soil simulant TRI – 1, two plain rigid wheels are considered, i.e., small wheel (dia. of 210 mm and width of 50 mm) and large wheel (dia. 160 mm and width 32 mm). Also, different number of lugs (N = 8, 12, 16) with various lug heights (h = 5 mm, 10 mm, 15 mm) are used. In this paper, the variation of wheel sinkages from experiments obtained for various wheel weights are examined and presented. The parameter, Coefficient of rolling resistance (CRR) is determined for various cases. Hence, rolling resistance was determined and examined from the obtained CRR for all cases. Among the cases examined, the large wheel with weight 67.44 N for plain wheels and weight 67.85 N for lugged wheel (no. of lugs = 16, and height of lugs = 5 mm) registered better mobility. Similarly, for small wheel with weight 52.189 N for plain wheel and weight 52.481 N for lugged wheel (no. of lugs = 16, and height of lugs = 5 mm) registered better mobility, a lesser rolling resistance for these cases.

Wheeled hopping robot

DOEpatents

Fischer, Gary J [Albuquerque, NM

2010-08-17

The present invention provides robotic vehicles having wheeled and hopping mobilities that are capable of traversing (e.g. by hopping over) obstacles that are large in size relative to the robot and, are capable of operation in unpredictable terrain over long range. The present invention further provides combustion powered linear actuators, which can include latching mechanisms to facilitate pressurized fueling of the actuators, as can be used to provide wheeled vehicles with a hopping mobility.

Stair-climbing capabilities of USU's T3 ODV mobile robot

NASA Astrophysics Data System (ADS)

Robinson, D. Reed; Wood, Carl G.

2001-09-01

A six-wheeled autonomous omni-directional vehicle (ODV) called T3 has been developed at Utah State University's (USU) Center for Self-Organizing and Intelligent Systems (CSOIS). This paper focuses on T3's ability to climb stairs using its unique configuration of 6 independently driven and steered wheels and active suspension height control. The ability of T3, or any similar vehicle, to climb stairs is greatly dependent on the chassis orientation relative to the stairs. Stability criteria is developed for any vehicle dimensions and orientation, on any staircase. All possible yaw and pitch angles on various staircases are evaluated to find vehicle orientations that will allow T3 to climb with the largest margin of stability. Different controller types are investigated for controlling vertical wheel movement with the objective of keeping all wheels in contact with the stairs, providing smooth load transfer between loaded and unloaded wheels, and maintaining optimum chassis pitch and roll angles. A controller is presented that uses feedback from wheel loading, vertical wheel position, and chassis orientation sensors. The implementation of the controller is described, and T3's stair climbing performance is presented and evaluated.

A predictive wheel-soil interaction model for planetary rovers validated in testbeds and against MER Mars rover performance data

NASA Astrophysics Data System (ADS)

Richter, L.; Ellery, A.; Gao, Y.; Michaud, S.; Schmitz, N.; Weiss, S.

Successful designs of vehicles intended for operations on planetary objects outside the Earth demand, just as for terrestrial off-the-road vehicles, a careful assessment of the terrain relevant for the vehicle mission and predictions of the mobility performance to allow rational trade-off's to be made for the choice of the locomotion concept and sizing. Principal issues driving the chassis design for rovers are the stress-strain properties of the planetary surface soil, the distribution of rocks in the terrain representing potential obstacles to movement, and the gravity level on the celestial object in question. Thus far, planetary rovers have been successfully designed and operated for missions to the Earth's moon and to the planet Mars, including NASA's Mars Exploration Rovers (MER's) `Spirit' and `Opportunity' being in operation on Mars since their landings in January 2004. Here we report on the development of a wheel-soil interaction model with application to wheel sizes and wheel loads relevant to current and near-term robotic planetary rovers, i.e. wheel diameters being between about 200 and 500 mm and vertical quasistatic wheel loads in operation of roughly 100 to 200 N. Such a model clearly is indispensable for sizings of future rovers to analyse the aspect of rover mobility concerned with motion across soils. This work is presently funded by the European Space Agency (ESA) as part of the `Rover Chassis Evaluation Tools' (RCET) effort which has developed a set of S/W-implemented models for predictive mobility analysis of rovers in terms of movement on soils and across obstacles, coupled with dedicated testbeds to validate the wheel-soil models. In this paper, we outline the details of the wheel-soil modelling performed within the RCET work and present comparisons of predictions of wheel performance (motion resistance, torque vs. slip and drawbar pull vs. slip) for specific test cases with the corresponding measurements performed in the RCET single wheel testbed and in the RCET system-level testbed, the latter permitting drawbar pull vs. slip measurements for complete rover development vehicles under controlled and homogeneous soil conditions. Required modifications of the wheel-soil model, in particular related to modelling the effect of wheel slip, are discussed. To strengthen the model validation base, we have run single wheel measurements using a spare MER Mars rover wheel and have performed comparisons with MER actual mobility performance data, available through one of us (LR) who is a member of the MER Athena science team. Corresponding results will be presented. Keywords: rovers, wheel, soil, mobility, vehicle performance, RCET (Rover Chassis Evaluation Tools), MER (Mars Exploration Rover mission) 2

Study on general theory of kinematics and dynamics of wheeled mobile robots

NASA Astrophysics Data System (ADS)

Tsukishima, Takahiro; Sasaki, Ken; Takano, Masaharu; Inoue, Kenji

1992-03-01

This paper proposes a general theory of kinematics and dynamics of wheeled mobile robots (WMRs). Unlike robotic manipulators which are modeled as 3-dimensional serial link mechanism, WMRs will be modeled as planar linkage mechanism with multiple links branching out from the base and/or another link. Since this model resembles a tree with branches, it will be called 'tree-structured-link'. The end of each link corresponds to the wheel which is in contact with the floor. In dynamics of WMR, equation of motion of a WMR is derived from joint input torques incorporating wheel dynamics. The wheel dynamics determines forces and moments acting on wheels as a function of slip velocity. This slippage of wheels is essential in dynamics of WMR. It will also be shown that the dynamics of WMR reduces to kinematics when slippage of wheels is neglected. Furthermore, the equation of dynamics is rewritten in velocity input form, since most of industrial motors are velocity controlled.

An overview on real-time control schemes for wheeled mobile robot

NASA Astrophysics Data System (ADS)

Radzak, M. S. A.; Ali, M. A. H.; Sha’amri, S.; Azwan, A. R.

2018-04-01

The purpose of this paper is to review real-time control motion algorithms for wheeled mobile robot (WMR) when navigating in environment such as road. Its need a good controller to avoid collision with any disturbance and maintain a track error at zero level. The controllers are used with other aiding sensors to measure the WMR’s velocities, posture, and interference to estimate the required torque to be applied on the wheels of mobile robot. Four main categories for wheeled mobile robot control systems have been found in literature which are namely: Kinematic based controller, Dynamic based controllers, artificial intelligence based control system, and Active Force control. A MATLAB/Simulink software is the main software to simulate and implement the control system. The real-time toolbox in MATLAB/SIMULINK are used to receive/send data from sensors/to actuator with presence of disturbances, however others software such C, C++ and visual basic are rare to be used.

Investigation of the Feasibility of an Intervention to Manage Fall Risk in Wheeled Mobility Device Users with Multiple Sclerosis.

PubMed

Rice, Laura A; Isaacs, Zadok; Ousley, Cherita; Sosnoff, Jacob

2018-01-01

Falls are a common concern for wheeled mobility device users with multiple sclerosis (MS); however, no evidence-based fall prevention programs have been developed to meet the specific needs of the population. We examine the preliminary feasibility of a fall management intervention in wheeled mobility device users with MS. Study participants were exposed to an intervention program targeting risk factors for falls, including transfer skills and seated postural control. The feasibility of the program was evaluated by assessing participant perspectives, cost, recruitment rates, study adherence, participant retention, safety, and the ability to collect primary and secondary outcomes, including fall frequency, concerns about falling, transfer quality, and seated postural control. 16 wheeled mobility device users completed the program, which was found to be feasible and was positively evaluated by participants. No adverse events were experienced. After exposure to the intervention, fall frequency significantly decreased (P < .001) and transfer quality (P = .001) and seated postural control (P = .002) significantly improved. No significant differences were found regarding concerns about falling (P = .728). This study examined the feasibility of an intervention program to manage fall risk in wheeled mobility device users with MS. The program was found to be feasible, and preliminary results showed the intervention to be effective in decreasing fall frequency. Additional testing is needed to further examine the efficacy and long-term impact of the intervention.

Leg pairs as virtual wheels

NASA Astrophysics Data System (ADS)

Howe, Russel; Duttweiler, Mark; Khanlian, Luke; Setrakian, Mark

2005-05-01

We propose the use of virtual wheels as the starting point of a new vehicle design. Each virtual wheel incorporates a pair of simple legs that, by simulating the rotary motion and ground contact of a traditional wheel, combine many of the benefits of legged and wheeled motion. We describe the use of virtual wheels in the design of a robotic mule, presenting an analysis of the mule's mobility the results of our efforts to model and build such a device.

Design of a wheeled articulating land rover

NASA Technical Reports Server (NTRS)

Stauffer, Larry; Dilorenzo, Mathew; Yandle, Barbara

1994-01-01

The WALRUS is a wheeled articulating land rover that will provide Ames Research Center with a reliable, autonomous vehicle for demonstrating and evaluating advanced technologies. The vehicle is one component of the Ames Research Center's on-going Human Exploration Demonstration Project. Ames Research Center requested a system capable of traversing a broad spectrum of surface types and obstacles. In addition, this vehicle must have an autonomous navigation and control system on board and its own source of power. The resulting design is a rover that articulates in two planes of motion to allow for increased mobility and stability. The rover is driven by six conical shaped aluminum wheels, each with an independent, internally coupled motor. Mounted on the rover are two housings and a removable remote control system. In the housings, the motor controller board, tilt sensor, navigation circuitry, and QED board are mounted. Finally, the rover's motors and electronics are powered by thirty C-cell rechargeable batteries, which are located in the rover wheels and recharged by a specially designed battery charger.

Speed Daemon: Experience-Based Mobile Robot Speed Scheduling

DTIC Science & Technology

2014-10-01

a wheeled mobile robot. Robotica , 20(2): 181–193, 2002. [7] O. Purwin and R. D‘Andrea. Trajectory generation and control for four wheeled...robot on an uneven surface. Robotica , 27(4):481–498, 2009. [9] S. Thrun, M. Montemerlo, H. Dahlkamp, D. Stavens, A. Aron, J. Diebel, P. Fong, J. Gale

Global Output-Feedback Control for Simultaneous Tracking and Stabilization of Wheeled Mobile Robots

NASA Astrophysics Data System (ADS)

Chang, J.; Zhang, L. J.; Xue, D.

A time-varying global output-feedback controller is presented that solves both tracking and stabilization for wheeled mobile robots simultaneously at the torque level. The controller synthesis is based on a coordinate transformation, Lyapunov direct method and backstepping technique. The performance of the proposed controller is demonstrated by simulation.

Guide To Mobile Aircraft Arresting System Installation - Air Force Handbook 10-222, Volume 8

DTIC Science & Technology

2000-03-01

38. Anchor Connection at Right Rear Wheel .................................................66 39. Store Tire Away from Runway – Right MAAS Trailer...MAAS Trailer .......68 42. Right Rear Wheel Anchor Point – Right MAAS Trailer.......................68 43. Right Rear Wheel Anchor Point Using...Rear Wheel .......................................73 47. Store Tire Away from Runway – Both MAAS Trailers ........................74 48. Left Rear

29 CFR 1910.211 - Definitions.

Code of Federal Regulations, 2011 CFR

2011-07-01

... having a diameter, thickness and wall—wheel is mounted on the diameter. (3) Type 6 straight cup wheels...—Type 6 Straight Cup Wheels EC27OC91.054 Type 6—Straight-cup Wheel Side grinding wheel having a diameter... describe this shape type. (4) Type 11 flaring cup wheels mean wheels having double diameter dimensions D...

Applicability of the Remote Mobile Emplacement Package (RMEP) design as a mobility aid for proposed post-84 Mars missions, phase O

NASA Technical Reports Server (NTRS)

1978-01-01

The results of study to determine the applicability of the Remote Mobile Emplacement Package (RMEP) design concept as a mobility aid for the proposed post-'84 Mars missions are presented. The RMEP wheel and mobility subsystem parameters: wheel tire size, weight, stowed volume, and environmental effects; obstacle negotiation; reliability and wear; motor and drive train; and electrical power demand were reviewed. Results indicated that: (1) the basic RMEP wheel design would be satisfactory, with additional attention to heating, side loading, tread wear and ultraviolet radiation protection; (2) motor and drive train power requirements on Mars would be less than on Earth; and (3) the mobility electrical power requirements would be small enough to offer the option of operating the Mars mini rover untethered. Payload power required for certain sampling functions would preclude the use of battery power for these missions. Hazard avoidance and reverse direction maneuvers are discussed. Limited examination of vehicle payload integration and thermal design was made, pending establishment of a baseline vehicle/payload design.

[Active and safe with wheeled walkers : Pilot study on feasibility of mobility exercises for wheeled walker users].

PubMed

Pflaum, Marina; Lang, Frieder R; Freiberger, Ellen

2016-07-01

The number of older people with mobility impairments using wheeled walkers is increasing; however, the handling of these walking aids is often ineffective. Moreover, age-associated functional loss, environmental demands and fear of falling may additionally challenge mobility. The new training program "Active and safe with wheeled walkers" aims to enhance skills and to improve mobility. The present pilot study was carried out to assess the feasibility of the training as well as to identify training effects and methodological insights for further research. The study was carried out with 28 wheeled walker users (age 68-91 years) in assisted living facilities using a pre-post design. Of the participants 13 persons were trained for 10 weeks (90 min, twice a week) and 15 persons served as a control group. Data were collected on functional mobility, hand strength, leg strength, balance, walker handling and fear of falling. The drop-out rate for the training was 38 % due to health concerns (n = 2), lack of time (n = 1) and changes in health status independent of training (n = 3). Medium to large effects were detected. Data regarding the recruitment strategy and the acceptance of individual exercises are available. The results indicate a good feasibility and effectiveness of the training. The simple accessibility of the training was conducive for the regular participation. The everyday relevance of the results and the lack of comparable interventions suggest that further research efforts be carried out. Recruitment strategies, training requirements and data collection methods need to be optimized.

Design features that affect the maneuverability of wheelchairs and scooters.

PubMed

Koontz, Alicia M; Brindle, Eric D; Kankipati, Padmaja; Feathers, David; Cooper, Rory A

2010-05-01

To determine the minimum space required for wheeled mobility device users to perform 4 maneuverability tasks and to investigate the impact of selected design attributes on space. Case series. University laboratory, Veterans Affairs research facility, vocational training center, and a national wheelchair sport event. The sample of convenience included manual wheelchair (MWC; n=109), power wheelchair (PWC; n=100), and scooter users (n=14). A mock environment was constructed to create passageways to form an L-turn, 360 degrees -turn in place, and a U-turn with and without a barrier. Passageway openings were increased in 5-cm increments until the user could successfully perform each task without hitting the walls. Structural dimensions of the device and user were collected using an electromechanical probe. Mobility devices were grouped into categories based on design features and compared using 1-way analysis of variance and post hoc pairwise Bonferroni-corrected tests. Minimum passageway widths for the 4 maneuverability tasks. Ultralight MWCs with rear axles posterior to the shoulder had the shortest lengths and required the least amount of space compared with all other types of MWCs (P<.05). Mid-wheel-drive PWCs required the least space for the 360 degrees -turn in place compared with front-wheel-drive and rear-wheel-drive PWCs (P<.01) but performed equally as well as front-wheel-drive models on all other turning tasks. PWCs with seat functions required more space to perform the tasks. Between 10% and 100% of users would not be able to maneuver in spaces that meet current Accessibility Guidelines for Buildings and Facilities specifications. This study provides data that can be used to support wheelchair prescription and home modifications and to update standards to improve the accessibility of public areas.

An Innovative Running Wheel-based Mechanism for Improved Rat Training Performance.

PubMed

Chen, Chi-Chun; Yang, Chin-Lung; Chang, Ching-Ping

2016-09-19

This study presents an animal mobility system, equipped with a positioning running wheel (PRW), as a way to quantify the efficacy of an exercise activity for reducing the severity of the effects of the stroke in rats. This system provides more effective animal exercise training than commercially available systems such as treadmills and motorized running wheels (MRWs). In contrast to an MRW that can only achieve speeds below 20 m/min, rats are permitted to run at a stable speed of 30 m/min on a more spacious and high-density rubber running track supported by a 15 cm wide acrylic wheel with a diameter of 55 cm in this work. Using a predefined adaptive acceleration curve, the system not only reduces the operator error but also trains the rats to run persistently until a specified intensity is reached. As a way to evaluate the exercise effectiveness, real-time position of a rat is detected by four pairs of infrared sensors deployed on the running wheel. Once an adaptive acceleration curve is initiated using a microcontroller, the data obtained by the infrared sensors are automatically recorded and analyzed in a computer. For comparison purposes, 3 week training is conducted on rats using a treadmill, an MRW and a PRW. After surgically inducing middle cerebral artery occlusion (MCAo), modified neurological severity scores (mNSS) and an inclined plane test were conducted to assess the neurological damages to the rats. PRW is experimentally validated as the most effective among such animal mobility systems. Furthermore, an exercise effectiveness measure, based on rat position analysis, showed that there is a high negative correlation between the effective exercise and the infarct volume, and can be employed to quantify a rat training in any type of brain damage reduction experiments.

Demographics and Trends in Wheeled Mobility Equipment Use and Accessibility in the Community

ERIC Educational Resources Information Center

LaPlante, Mitchell P.; Kaye, H. Stephen

2010-01-01

This article presents a profile of household-resident U.S. adults using wheeled mobility equipment (WME) in 2005, trends in WME use from 1990 to 2005, and data on accessibility features and problems from 1994-97. Data were obtained from the Survey of Income and Program Participation (SIPP) and the National Health Interview Survey on Disability…

Wheeled mobility device transportation safety in fixed route and demand-responsive public transit vehicles within the United States.

PubMed

Frost, Karen L; van Roosmalen, Linda; Bertocci, Gina; Cross, Douglas J

2012-01-01

An overview of the current status of wheelchair transportation safety in fixed route and demand-responsive, non-rail, public transportation vehicles within the US is presented. A description of each mode of transportation is provided, followed by a discussion of the primary issues affecting safety, accessibility, and usability. Technologies such as lifts, ramps, securement systems, and occupant restraint systems, along with regulations and voluntary industry standards have been implemented with the intent of improving safety and accessibility for individuals who travel while seated in their wheeled mobility device (e.g., wheelchair or scooter). However, across both fixed route and demand-responsive transit systems a myriad of factors such as nonuse and misuse of safety systems, oversized wheeled mobility devices, vehicle space constraints, and inadequate vehicle operator training may place wheeled mobility device (WhMD) users at risk of injury even under non-impact driving conditions. Since WhMD-related incidents also often occur during the boarding and alighting process, the frequency of these events, along with factors associated with these events are described for each transit mode. Recommendations for improving WhMD transportation are discussed given the current state of

Walk and roll robot

NASA Technical Reports Server (NTRS)

Wilson, Andrew (Inventor); Punnoose, Andrew (Inventor); Strausser, Katherine (Inventor); Parikh, Neil (Inventor)

2011-01-01

A mobile robotic unit features a main body, a plurality of legs for supporting the main body on and moving the main body in forward and reverse directions about a base surface, and a drive assembly. According to an exemplary embodiment each leg includes a respective pivotal hip joint, a pivotal knee joint, and a wheeled foot adapted to roll along the base surface. Also according to an exemplary embodiments the drive assembly includes a motor operatively associated with the hip and knee joints and the wheeled foot for independently driving pivotal movement of the hip joint and the knee joint and rolling motion of the wheeled foot. The hip joint may include a ball-and-socket-type joint interconnecting top portion of the leg to the main body, such that the hip joint is adapted to pivot said leg in a direction transverse to a forward-and-reverse direction.

mobilityRERC state of the science conference: Considerations for developing an evidence base for wheeled mobility and seating service delivery.

PubMed

Cohen, Laura; Greer, Nancy; Berliner, Elise; Sprigle, Stephen

2013-11-01

This article, developed as background content for discussion during the Mobility Rehabilitation Engineering Research Center State of the Science Conference, reviews research surrounding wheeled mobility and seating (WMS) service delivery, discusses the challenges of improving clinical decision-making, and discusses research approaches used to study and improve health services in other practice areas that might be leveraged to develop the evidence base for WMS. Narrative literature review. An overview of existing research found general agreement across models of WMS service delivery but little high quality evidence to support the recommended approaches and few studies of the relationship between service delivery steps and individual patient outcomes. The definition of successful clinical decision-making is different for different stakeholders. Clinical decision-making should incorporate the best available evidence along with patient values, preferences, circumstances, and clinical expertise. To advance the evidence base for WMS service delivery, alternatives to randomized controlled trials should be considered and reliable and valid outcome measures developed. Technological advances offer tremendous opportunities for individuals with complex rehabilitation technology needs. However, with ongoing scrutiny of WMS service delivery there is an increased need for evidence to support the clinical decision-making process and to support evidence-based coverage policies for WMS services and technologies. An evidence base for wheeled mobility and seating services is an important component of the clinical decision-making process. At present, there is little evidence regarding essential components of the wheeled mobility and seating evaluation or the relationship between the evaluation process and patient outcomes. Many factors can confound this relationship and present challenges to research in this area. All stakeholders (i.e. clinicians, rehabilitation technology suppliers, manufacturers, researchers, payers, policy makers, and wheelchair users) need to work together to develop and support an evidence base for wheeled mobility and seating service delivery.

Characterization Parameters for a Three Degree of Freedom Mobile Robot

DTIC Science & Technology

2013-12-01

DARc’s dimensions which contributed to the inertia, force, torque and position equa- tions. We calculated body inertia as 1.93kg·m2 and wheel inertia...separation .316 Wheel Radius Outer/Inner .127 m .085cm Wheel Mass .7055 kg Body Mass 13.542 kg Table 4.1: DAR-C Dimensions The force on each wheel...which used ackeman steering, a technique where wheels are able to rotate relative the robot body . The easiest example of a differentially steered

Effects of transit bus interior configuration on performance of wheeled mobility users during simulated boarding and disembarking.

PubMed

D'Souza, Clive; Paquet, Victor; Lenker, James A; Steinfeld, Edward

2017-07-01

The emergence of low-floor bus designs and related regulatory standards in the U.S. have resulted in substantial improvements in public transit accessibility. However, passengers using wheeled mobility devices still experience safety concerns and inefficiencies in boarding, disembarking, and interior circulation on low-floor buses. This study investigates effects of low-floor bus interior configuration and passenger crowding on boarding and disembarking efficiency and safety. Users of manual wheelchairs (n = 18), powered wheelchairs (n = 21) and electric scooters (n = 9) simulated boarding and disembarking in three interior layout configurations at low and high passenger crowding conditions on a full-scale laboratory mock-up of a low-floor bus. Dependent measures comprised task times and critical incidents during access ramp use, fare payment, and movement to and from the doorway and wheeled mobility securement area. Individual times for unassisted boarding ranged from 15.2 to 245.3 s and for disembarking ranged from 9.1 to 164.6 s across layout and passenger crowding conditions. Nonparametric analysis of variance showed significant differences and interactions across vehicle design conditions, passenger load and mobility device type on user performance. The configuration having electronic on-board fare payment, rear-bus entrance doorways and adjacent device securement areas demonstrated greatest efficiency and safety. High passenger load adversely impacted efficiency and frequency of critical incidents during on-board circulation across all three layouts. Findings have broader implications for improving transit system efficiency and quality of service across the spectrum of transit users. Copyright © 2017 Elsevier Ltd. All rights reserved.

Suspension Parameter Measurements of Wheeled Military Vehicles

DTIC Science & Technology

2012-08-01

suspension through the wheel pads. The SPIdER was designed so that in the future, with a modest amount of modification , it can be upgraded to include the...AND MOBILITY (P&M) MINI-SYMPOSIUM AUGUST 14-16, MICHIGAN SUSPENSION PARAMETER MEASUREMENTS OF WHEELED MILITARY VEHICLES Dale Andreatta Gary...was built to measure the suspension parameters of any military wheeled vehicle. This is part of an ongoing effort to model and predict vehicle

Wheeled-mobility correlates of life-space and social participation in adult manual wheelchair users aged 50 and older.

PubMed

Sakakibara, Brodie M; Routhier, François; Miller, William C

2017-08-01

To characterize the life-space mobility and social participation of manual wheelchair users using objective measures of wheeled mobility. Individuals (n = 49) were included in this cross-sectional study if they were aged 50 or older, community-dwelling and used their wheelchair on a daily basis for the past 6 months. Life-space mobility and social participation were measured using the life-space assessment and late-life disability instrument. The wheeled mobility variables (distance travelled, occupancy time, number of bouts) were captured using a custom-built data logger. After controlling for age and sex, multivariate regression analyses revealed that the wheeled mobility variables accounted for 24% of the life-space variance. The number of bouts variable, however, did not account for any appreciable variance above and beyond the occupancy time and distance travelled. Occupancy time and number of bouts were significant predictors of social participation and accounted for 23% of the variance after controlling for age and sex. Occupancy time and distance travelled are statistically significant predictors of life-space mobility. Lower occupancy time may be an indicative of travel to more distant life-spaces, whereas the distance travelled is likely a better reflection of mobility within each life-space. Occupancy time and number of bouts are significant predictors of participation frequency. Implications for rehabilitation Component measures of wheelchair mobility, such as distance travelled, occupancy time and number of bouts, are important predictors of life-space mobility and social participation in adult manual wheelchair users. Lower occupancy time is an indication of travel to more distant life-spaces, whereas distance travelled is likely a better reflection of mobility within each life-space. That lower occupancy time and greater number of bouts are associated with more frequent participation raises accessibility and safety issues for manual wheelchair users.

Hopping Robot with Wheels

NASA Technical Reports Server (NTRS)

Barlow, Edward; Marzwell, Nevellie; Fuller, Sawyer; Fionni, Paolo; Tretton, Andy; Burdick, Joel; Schell, Steve

2003-01-01

A small prototype mobile robot is capable of (1) hopping to move rapidly or avoid obstacles and then (2) moving relatively slowly and precisely on the ground by use of wheels in the manner of previously reported exploratory robots of the "rover" type. This robot is a descendant of a more primitive hopping robot described in "Minimally Actuated Hopping Robot" (NPO- 20911), NASA Tech Briefs, Vol. 26, No. 11 (November 2002), page 50. There are many potential applications for robots with hopping and wheeled-locomotion (roving) capabilities in diverse fields of endeavor, including agriculture, search-and-rescue operations, general military operations, removal or safe detonation of land mines, inspection, law enforcement, and scientific exploration on Earth and remote planets. The combination of hopping and roving enables this robot to move rapidly over very rugged terrain, to overcome obstacles several times its height, and then to position itself precisely next to a desired target. Before a long hop, the robot aims itself in the desired hopping azimuth and at a desired takeoff angle above horizontal. The robot approaches the target through a series of hops and short driving operations utilizing the steering wheels for precise positioning.

In-situ soil sensing for planetary micro-rovers with hybrid wheel-leg systems

NASA Astrophysics Data System (ADS)

Comin Cabrera, Francisco Jose

Rover missions exploring other planets are tightly constrained regarding the trade-off between safety and traversal speed. Detecting and avoiding hazards during navigation is capital to preserve the mobility of a rover. Low traversal speeds are often enforced to assure that wheeled rovers do not become stuck in challenging terrain, hindering the performance and scientific return of the mission. Even such precautions do not guarantee safe navigation due to non-geometric hazards hidden in the terrain, such as sand traps beneath thin duricrusts. These issues motivate the research of the interaction with rough and sandy planetary terrains of conventional and innovative robot locomotion concepts. Hybrid wheel-legs combine the mechanical and control simplicity of wheeled locomotion with the enhanced mobility of legged locomotion. This concept has been rarely proposed for planetary exploration and the study of its interaction with granular terrains is at a very early stage. This research focuses on advancing the state-of-the-art of wheel-leg-soil interaction analysis and applying it through in-situ sensing to simultaneously improve the speed and safety of planetary rover missions. The semi-empirical approach used combines both theoretical modelling and experimental analysis of data obtained in laboratory and field analogues. A novel light-weight, low-power sensor system, capable of reliably detecting wheel-leg sinkage and slippage phenomena on-the-fly, is designed, implemented and tested both as part of a simplified single-wheel-leg test bed and integrated in a fully mobile micro-rover. Moreover, existing analytical models for the interaction between deformable terrain and heavily-loaded wheels or lightly-loaded legs are adapted to the generalised medium-loaded multi-legged wheel-leg case and combined into hybrid approaches for better accuracy, as validated against experimental data. Finally, the soil sensor system and analytical models proposed are used to develop and prove the effectiveness of different solutions for soil characterisation, trafficability assessment and terrain classification based on non-geometric physical properties.

Verification hybrid control of a wheeled mobile robot and manipulator

NASA Astrophysics Data System (ADS)

Muszynska, Magdalena; Burghardt, Andrzej; Kurc, Krzysztof; Szybicki, Dariusz

2016-04-01

In this article, innovative approaches to realization of the wheeled mobile robots and manipulator tracking are presented. Conceptions include application of the neural-fuzzy systems to compensation of the controlled system's nonlinearities in the tracking control task. Proposed control algorithms work on-line, contain structure, that adapt to the changeable work conditions of the controlled systems, and do not require the preliminary learning. The algorithm was verification on the real object which was a Scorbot - ER 4pc robotic manipulator and a Pioneer - 2DX mobile robot.

A multi-mode real-time terrain parameter estimation method for wheeled motion control of mobile robots

NASA Astrophysics Data System (ADS)

Li, Yuankai; Ding, Liang; Zheng, Zhizhong; Yang, Qizhi; Zhao, Xingang; Liu, Guangjun

2018-05-01

For motion control of wheeled planetary rovers traversing on deformable terrain, real-time terrain parameter estimation is critical in modeling the wheel-terrain interaction and compensating the effect of wheel slipping. A multi-mode real-time estimation method is proposed in this paper to achieve accurate terrain parameter estimation. The proposed method is composed of an inner layer for real-time filtering and an outer layer for online update. In the inner layer, sinkage exponent and internal frictional angle, which have higher sensitivity than that of the other terrain parameters to wheel-terrain interaction forces, are estimated in real time by using an adaptive robust extended Kalman filter (AREKF), whereas the other parameters are fixed with nominal values. The inner layer result can help synthesize the current wheel-terrain contact forces with adequate precision, but has limited prediction capability for time-variable wheel slipping. To improve estimation accuracy of the result from the inner layer, an outer layer based on recursive Gauss-Newton (RGN) algorithm is introduced to refine the result of real-time filtering according to the innovation contained in the history data. With the two-layer structure, the proposed method can work in three fundamental estimation modes: EKF, REKF and RGN, making the method applicable for flat, rough and non-uniform terrains. Simulations have demonstrated the effectiveness of the proposed method under three terrain types, showing the advantages of introducing the two-layer structure.

Combustion powered linear actuator

DOEpatents

Fischer, Gary J.

2007-09-04

The present invention provides robotic vehicles having wheeled and hopping mobilities that are capable of traversing (e.g. by hopping over) obstacles that are large in size relative to the robot and, are capable of operation in unpredictable terrain over long range. The present invention further provides combustion powered linear actuators, which can include latching mechanisms to facilitate pressurized fueling of the actuators, as can be used to provide wheeled vehicles with a hopping mobility.

A new family of omnidirectional and holonomic wheeled platforms for mobile robots

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

Pin, F.G.; Killough, S.M.

1994-08-01

This paper presents the concepts for a new family of holonomic wheeled platforms that feature full omnidirectionality with simultaneous and independently controlled rotational and translational motion capabilities. The authors first present the orthogonal-wheels'' concept and the two major wheel assemblies on which these platforms are based. The authors then describe how a combination of these assemblies with appropriate control can be used to generate an omnidirectional capability for mobile robot platforms. Several alternative designs are considered, and their respective characteristics with respect to rotational and translational motion control are discussed. The design and control of a prototype platform developed tomore » test and demonstrate the proposed concepts is then described, and experimental results illustrating the full omnidirectionality of the platforms with decoupled rotational and translational degrees of freedom are presented.« less

Micro unattended mobility system (MUMS)

NASA Astrophysics Data System (ADS)

Rudakevych, Pavlo; Greiner, Helen; Pletta, Bryan

1999-07-01

This report covers work under phase one of the Micro Unattended Mobility System project investigating the addition of a mobile sensor components to existing and future ground penetrator delivered unattended sensor systems. A typical unattended sensor strategy consists of air-dropping sensor packages into a target terrain for remote observation and intelligence gathering. Existing and planned unattended systems have no control over their location after the drop is complete. We propose to augment the capability of these sensing packages by giving them a degree of local mobility. From an assumed operational scenario, vehicle design specifications are identified that would be required for mission success. Three basic mobility concepts are presented and evaluated for their strengths and weaknesses in the proposed mission. The mobility concepts are grouped into wheeled, jumping, and crawling systems. Of the three mobility concepts discussed, the system that shows the most promise is presented in a more detailed design. This design consists of two side by side wheels which drag a reaction tail behind them. The control electronics, batteries, and drive motors are housed in a central body connected to the tail and two sensor payloads can be placed in the wheel hubs. This design is proposed for further development and testing in the second phase of this project.

ATHLETE: A Limbed Vehicle for Solar System Exploration

NASA Technical Reports Server (NTRS)

Wilcox, Brian H.

2012-01-01

As part of the Human-Robot Systems project funded by NASA, the Jet Propulsion Laboratory has developed a vehicle called ATHLETE: the All-Terrain Hex-Limbed Extra-Terrestrial Explorer. Each vehicle is based on six wheels at the ends of six multi-degree-of-freedom limbs. Because each limb has enough degrees of freedom for use as a general-purpose leg, the wheels can be locked and used as feet to walk out of excessively soft or other extreme terrain. Since the vehicle has this alternative mode of traversing through or at least out of extreme terrain, the wheels and wheel actuators can be sized for nominal terrain. There are substantial mass savings in the wheel and wheel actuators associated with designing for nominal instead of extreme terrain. These mass savings are comparable-to or larger-than the extra mass associated with the articulated limbs. As a result, the entire mobility system, including wheels and limbs, can be about 25% lighter than a conventional mobility chassis. A side benefit of this approach is that each limb has sufficient degrees-of-freedom to use as a general-purpose manipulator (hence the name "limb" instead of "leg"). Our prototype ATHLETE vehicles have quick-disconnect tool adapters on the limbs that allow tools to be drawn out of a "tool belt" and maneuvered by the limb.

Adaptive tracking control of a wheeled mobile robot via an uncalibrated camera system.

PubMed

Dixon, W E; Dawson, D M; Zergeroglu, E; Behal, A

2001-01-01

This paper considers the problem of position/orientation tracking control of wheeled mobile robots via visual servoing in the presence of parametric uncertainty associated with the mechanical dynamics and the camera system. Specifically, we design an adaptive controller that compensates for uncertain camera and mechanical parameters and ensures global asymptotic position/orientation tracking. Simulation and experimental results are included to illustrate the performance of the control law.

Sensor deployment on unmanned ground vehicles

NASA Astrophysics Data System (ADS)

Gerhart, Grant R.; Witus, Gary

2007-10-01

TARDEC has been developing payloads for small robots as part of its unmanned ground vehicle (UGV) development programs. These platforms typically weigh less than 100 lbs and are used for various physical security and force protection applications. This paper will address a number of technical issues including platform mobility, payload positioning, sensor configuration and operational tradeoffs. TARDEC has developed a number of robots with different mobility mechanisms including track, wheel and hybrid track/wheel running gear configurations. An extensive discussion will focus upon omni-directional vehicle (ODV) platforms with enhanced intrinsic mobility for positioning sensor payloads. This paper also discusses tradeoffs between intrinsic platform mobility and articulated arm complexity for end point positioning of modular sensor packages.

Lyapunov vector function method in the motion stabilisation problem for nonholonomic mobile robot

NASA Astrophysics Data System (ADS)

Andreev, Aleksandr; Peregudova, Olga

2017-07-01

In this paper we propose a sampled-data control law in the stabilisation problem of nonstationary motion of nonholonomic mobile robot. We assume that the robot moves on a horizontal surface without slipping. The dynamical model of a mobile robot is considered. The robot has one front free wheel and two rear wheels which are controlled by two independent electric motors. We assume that the controls are piecewise constant signals. Controller design relies on the backstepping procedure with the use of Lyapunov vector-function method. Theoretical considerations are verified by numerical simulation.

Dollar Summary of Federal Supply Classification and Service Category by Company, FY84, Part 1 (1005-2610).

DTIC Science & Technology

1984-01-01

350 STATE TOTAL 377 NEBRASKA ARMY TRACTORS WHEELED 111 CONTRACTOR TOTAL 488 PINE BUSH EQUIPMENT CO INC NEW YORK ARMY TRACTORS WHEELED 49 PSI MOBILE...ARMY VEHICULAR FURNITURE AND ACCESSORIES 48- AURORA CORD a CABLE CO INC ILLINOIS ARMY VEHICULAR FURNITURE AND ACCESSORIES 211 BARREN RV MTL HTH/MTL...MICHIGAN ARMY VEHICULAR BRAKE STEERING AXLE WHEEL COMP 702 PENN ARMY VEHICULAR BRAKE STEERING AXLE WHEEL COMP 32 CONTRACTOR TOTAL 734 RYAN CHRYSLER PLYMOUTH

Utah State University's T2 ODV mobility analysis

NASA Astrophysics Data System (ADS)

Davidson, Morgan E.; Bahl, Vikas; Wood, Carl G.

2000-07-01

In response to ultra-high maneuverability vehicle requirements, Utah State University (USU) has developed an autonomous vehicle with unique mobility and maneuverability capabilities. This paper describes a study of the mobility of the USU T2 Omni-Directional Vehicle (ODV). The T2 vehicle is a mid-scale (625 kg), second-generation ODV mobile robot with six independently driven and steered wheel assemblies. The six wheel, independent steering system is capable of unlimited steering rotation, presenting a unique solution to enhanced vehicle mobility requirements. This mobility study focuses on energy consumption in three basic experiments, comparing two modes of steering: Ackerman and ODV. The experiments are all performed on the same vehicle without any physical changes to the vehicle itself, providing a direct comparison these two steering methodologies. A computer simulation of the T2 mechanical and control system dynamics is described.

Biomechanical effects of mobile computer location in a vehicle cab.

PubMed

Saginus, Kyle A; Marklin, Richard W; Seeley, Patricia; Simoneau, Guy G; Freier, Stephen

2011-10-01

The objective of this research is to determine the best location to place a conventional mobile computer supported by a commercially available mount in a light truck cab. U.S. and Canadian electric utility companies are in the process of integrating mobile computers into their fleet vehicle cabs. There are no publications on the effect of mobile computer location in a vehicle cab on biomechanical loading, performance, and subjective assessment. The authors tested four locations of mobile computers in a light truck cab in a laboratory study to determine how location affected muscle activity of the lower back and shoulders; joint angles of the shoulders, elbows, and wrist; user performance; and subjective assessment. A total of 22 participants were tested in this study. Placing the mobile computer closer to the steering wheel reduced low back and shoulder muscle activity. Joint angles of the shoulders, elbows, and wrists were also closer to neutral angle. Biomechanical modeling revealed substantially less spinal compression and trunk muscle force. In general, there were no practical differences in performance between the locations. Subjective assessment indicated that users preferred the mobile computer to be as close as possible to the steering wheel. Locating the mobile computer close to the steering wheel reduces risk of injuries, such as low back pain and shoulder tendonitis. Results from the study can guide electric utility companies in the installation of mobile computers into vehicle cabs. Results may also be generalized to other industries that use trucklike vehicles, such as construction.

ATHLETE: Lunar Cargo Unloading from a High Deck

NASA Technical Reports Server (NTRS)

Wilcox, Brian H.

2010-01-01

As part of the NASA Exploration Technology Development Program, the Jet Propulsion Laboratory is developing a vehicle called ATHLETE: the All-Terrain Hex-Limbed Extra-Terrestrial Explorer. Each vehicle is based on six wheels at the ends of six multi-degree-of freedom limbs. Because each limb has enough degrees of freedom for use as a general-purpose leg, the wheels can be locked and used as feet to walk out of excessively soft or other extreme terrain. Since the vehicle has this alternative mode of traversing through or at least out of extreme terrain, the wheels and wheel actuators can be sized for nominal terrain. There are substantial mass savings in the wheel and wheel actuators associated with designing for nominal instead of extreme terrain. These mass savings are at least comparable-to or larger-than the extra mass associated with the articulated limbs. As a result, the entire mobility system, including wheels and limbs, can be lighter than a conventional all-terrain mobility chassis. A side benefit of this approach is that each limb has sufficient degrees-of freedom to be used as a general-purpose manipulator (hence the name "limb" instead of "leg"). Our prototype ATHLETE vehicles have quick-disconnect tool adapters on the limbs that allow tools to be drawn out of a "tool belt" and maneuvered by the limb. A power-take-off from the wheel actuates the tools, so that they can take advantage of the 1+ horsepower motor in each wheel to enable drilling, gripping or other power-tool functions.

ATHLETE: a Cargo and Habitat Transporter for the Moon

NASA Technical Reports Server (NTRS)

Wilcox, Brian H.

2009-01-01

As part of the NASA Exploration Technology Development Program, the Jet Propulsion Laboratory is developing a vehicle called ATHLETE: the All-Terrain Hex-Limbed Extra-Terrestrial Explorer. The vehicle concept is based on six wheels at the ends of six multi-degree-of-freedom limbs. Because each limb has enough degrees of freedom for use as a general-purpose leg, the wheels can be locked and used as feet to walk out of excessively soft or other extreme terrain. Since the vehicle has this alternative mode of traversing through (or at least out of) extreme terrain, the wheels and wheel actuators can be sized only for nominal terrain. There are substantial mass savings in the wheels and wheel actuators associated with designing for nominal instead of extreme terrain. These mass savings are comparable-to or larger-than the extra mass associated with the articulated limbs. As a result, the entire mobility system, including wheels and limbs, can be about 25 percent lighter than a conventional mobility chassis for planetary exploration. A side benefit of this approach is that each limb has sufficient degrees-of-freedom for use as a general-purpose manipulator (hence the name "limb" instead of "leg"). Our prototype ATHLETE vehicles have quick-disconnect tool adapters on the limbs that allow tools to be drawn out of a "tool belt" and maneuvered by the limb. A rotating power-take-off from the wheel actuates the tools, so that they can take advantage of the 1-plus-horsepower motor in each wheel to enable drilling, gripping or other power-tool functions.

Increasing the Mobility of Dismounted Marines. Small Unit Mobility Enhancement Technologies: Unmanned Ground Vehicles Market Survey

DTIC Science & Technology

2009-10-01

DARPA) Legged Squad Support System (LS3) Program. DARPA’s LS3 Program is an effort to develop a walking platform, preferably a quadruped, which...top-scoring UGV’s are track- or wheel-based; only the BigDog is a leg -based system. This presented BigDog with certain advantages (particularly...Technologies, Inc.’s ( DTI ) first location in Ranlo, North Carolina) – is a system capable of wheeled or tracked locomotion and was recently

mobilityRERC state of the science: How science influences public policy in seating and mobility.

PubMed

Hostak, Rita S; Edwards, Doran; Sprigle, Stephen

2013-11-01

In the United States (US), wheeled mobility and seating equipment is classified as Durable Medical Equipment (DME). DME includes a wide array of devices including canes, walkers, home oxygen equipment, hospital beds, and wheelchairs. Seating and mobility devices reflect a wide range of DME, from relatively simple standard manual wheelchairs and cushions to highly complex manual and power wheelchairs and custom seating systems. This wide range of complexity results in a wide range of policies that govern the provision of seating and mobility equipment. This article results from a presentation during the Wheeled Mobility Rehabilitation Engineering Research Center's (RERC's) State of the Science Conference in 2012. The presentation was designed to proffer key concepts related to coverage policies and policy decision-making. Topics covered include an introduction to key policy issues impacting seating and mobility equipment, a description of the barriers that prevent or hinder research being used to inform coverage policy decisions, discussion of the challenges surrounding evidence-based policy decisions regarding seating and mobility, and suggestions of strategies for including policy makers and other stakeholders in setting research priorities and in reporting research findings. In the United States, wheeled mobility and seating equipment are classified as Durable Medical Equipments which are governed by a wide range of policies. Researchers should be encouraged to supplement research articles with articles that explicitly address clinical and policy implications of the work. Policy-makers should be encouraged to engage researchers to insure the breadth of knowledge and evidence is represented and understood.

Tri-wheeled scooters transported on buses and vans : assessment of securement restraint issues

DOT National Transportation Integrated Search

2005-10-01

Under the Americans with Disabilities Act (ADA) of 1990, all "common wheelchairs and mobility aids", including tri-wheeled scooters, must be accommodated on buses and vans used in public transit service. Several transit systems have recently expresse...

29 CFR 1910.241 - Definitions.

Code of Federal Regulations, 2011 CFR

2011-07-01

... reinforced does not cover wheels using such mechanical additions as steel rings, steel cup backs or wire or tape winding. (8) Type 11 flaring cup wheels. Type 11 flaring cup wheels have double diameter... mounting listed for Type 6 straight sided cup wheels definition in subparagraph (9) of this paragraph. Type...

29 CFR 1910.241 - Definitions.

Code of Federal Regulations, 2010 CFR

2010-07-01

... reinforced does not cover wheels using such mechanical additions as steel rings, steel cup backs or wire or tape winding. (8) Type 11 flaring cup wheels. Type 11 flaring cup wheels have double diameter... mounting listed for Type 6 straight sided cup wheels definition in subparagraph (9) of this paragraph. Type...

A mechanical model for deformable and mesh pattern wheel of lunar roving vehicle

NASA Astrophysics Data System (ADS)

Liang, Zhongchao; Wang, Yongfu; Chen, Gang (Sheng); Gao, Haibo

2015-12-01

As an indispensable tool for astronauts on lunar surface, the lunar roving vehicle (LRV) is of great significance for manned lunar exploration. An LRV moves on loose and soft lunar soil, so the mechanical property of its wheels directly affects the mobility performance. The wheels used for LRV have deformable and mesh pattern, therefore, the existing mechanical theory of vehicle wheel cannot be used directly for analyzing the property of LRV wheels. In this paper, a new mechanical model for LRV wheel is proposed. At first, a mechanical model for a rigid normal wheel is presented, which involves in multiple conventional parameters such as vertical load, tangential traction force, lateral force, and slip ratio. Secondly, six equivalent coefficients are introduced to amend the rigid normal wheel model to fit for the wheels with deformable and mesh-pattern in LRV application. Thirdly, the values of the six equivalent coefficients are identified by using experimental data obtained in an LRV's single wheel testing. Finally, the identified mechanical model for LRV's wheel with deformable and mesh pattern are further verified and validated by using additional experimental results.

Analysis of the individual factors affecting mobile phone use while driving in France: socio-demographic characteristics, car and phone use in professional and private contexts.

PubMed

Brusque, Corinne; Alauzet, Aline

2008-01-01

In France, as in many other countries, phoning while driving is legally restricted because of its negative impact on driving performance which increases accident risk. Nevertheless, it is still a frequently observed practice and one which has not been analyzed in detail. This study attempts to identify the profiles of those who use mobile phones while at the wheel and determine the forms taken by this use. A representative sample of 1973 French people was interviewed by phone on their driving practices and mobile phone use in everyday life and their mobile phone use while driving. Logistics regressions have been conducted to highlight the explanatory factors of phoning while driving. Strong differences between males and females have been shown. For the male population, age is the main explanatory factor of phoning while driving, followed by phone use for work-related reasons and extensive mobile phone use in everyday life. For females, high mileage and intensive use of mobile phone are the only two explanatory factors. We defined the intensive phone use at the wheel group as drivers who receive or send at least five or more calls per day while driving. There is no socio-demographic variable related to this practice. Car and phone uses in everyday life are the only explanatory factors for this intensive mobile use of the phone at the wheel.

Formation tracker design of multiple mobile robots with wheel perturbations: adaptive output-feedback approach

NASA Astrophysics Data System (ADS)

Yoo, Sung Jin

2016-11-01

This paper presents a theoretical design approach for output-feedback formation tracking of multiple mobile robots under wheel perturbations. It is assumed that these perturbations are unknown and the linear and angular velocities of the robots are unmeasurable. First, adaptive state observers for estimating unmeasurable velocities of the robots are developed under the robots' kinematics and dynamics including wheel perturbation effects. Then, we derive a virtual-structure-based formation tracker scheme according to the observer dynamic surface design procedure. The main difficulty of the output-feedback control design is to manage the coupling problems between unmeasurable velocities and unknown wheel perturbation effects. These problems are avoided by using the adaptive technique and the function approximation property based on fuzzy logic systems. From the Lyapunov stability analysis, it is shown that point tracking errors of each robot and synchronisation errors for the desired formation converge to an adjustable neighbourhood of the origin, while all signals in the controlled closed-loop system are semiglobally uniformly ultimately bounded.

Portable haptic interface with omni-directional movement and force capability.

PubMed

Avizzano, Carlo Alberto; Satler, Massimo; Ruffaldi, Emanuele

2014-01-01

We describe the design of a new mobile haptic interface that employs wheels for force rendering. The interface, consisting of an omni-directional Killough type platform, provides 2DOF force feedback with different control modalities. The system autonomously performs sensor fusion for localization and force rendering. This paper explains the relevant choices concerning the functional aspects, the control design, the mechanical and electronic solution. Experimental results for force feedback characterization are reported.

Modeling and Simulation of Two Wheelchair Accessories for Pushing Doors.

PubMed

Abdullah, Soran Jalal; Shaikh Mohammed, Javeed

2017-03-27

Independent mobility is vital to individuals of all ages, and wheelchairs have proven to be great personal mobility devices. The tasks of opening and navigating through a door are trivial for healthy people, while the same tasks could be difficult for some wheelchair users. A wide range of intelligent wheelchair controllers and systems, robotic arms, or manipulator attachments integrated with wheelchairs have been developed for various applications, including manipulating door knobs. Unfortunately, the intelligent wheelchairs and robotic attachments are not widely available as commercial products. Therefore, the current manuscript presents the modeling and simulation of a novel but simple technology in the form of a passive wheelchair accessory (straight, arm-like with a single wheel, and arc-shaped with multiple wheels) for pushing doors open from a wheelchair. From the simulations using different wheel shapes and sizes, it was found that the arc-shaped accessory could push open the doors faster and with almost half the required force as compared to the arm-like accessory. Also, smaller spherical wheels were found to be best in terms of reaction forces on the wheels. Prototypes based on the arc-shaped accessory design will be manufactured and evaluated for pushing doors open and dodging or gliding other obstacles.

Design and evaluation of a toroidal wheel for planetary rovers

NASA Technical Reports Server (NTRS)

Koskol, J.; Yerazunis, S. W.

1977-01-01

The inverted toroidal wheel concept was perceived, mathematically quantified, and experimentally verified. The wheel design has a number of important characteristics, namely; (1) the low footprint pressures required for Mars exploration (0.5 to 1.0 psi); (2) high vehicle weight to wheel weight ratios capable of exceeding 10:1; (3) extremely long cyclic endurances tending towards infinite life; and (4) simplicity of design. The concept, in combination with appropriate materials such as titanium or composites, provides a planetary roving vehicle with a very high degree of exploratory mobility, a substantial savings in weight and a high assurity of mission success. Design equations and computation procedures necessary to formulate an inverted wheel are described in detail.

Mobile Business Retailing: Driving Experiential Learning on Campus

ERIC Educational Resources Information Center

Fischbach, Sarah; Guerrero, Veronica

2018-01-01

Engaging students in the classroom is a struggle all faculty face especially in the age of modern technology. This article proposes a novel approach to engage and motivate students through the mobile business "on wheels" marketing concept. The growth in mobile business retailing (e.g., food trucks, mobile dog groomers, etc.) is an…

46 CFR 108.643 - Rudder orders.

Code of Federal Regulations, 2010 CFR

2010-10-01

... GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) A-MOBILE OFFSHORE DRILLING UNITS DESIGN AND EQUIPMENT... the wheel or steering device must be moved for right rudder or left rudder must be marked in letters of contrasting color to the background on the wheel or steering device or in a place that is directly...

A comparison of two types of running wheel in terms of mouse preference, health, and welfare.

PubMed

Walker, Michael; Mason, Georgia

2018-07-01

Voluntary wheel running occurs in mice of all strains, sexes, and ages. Mice find voluntary wheel running rewarding, and it leads to numerous health benefits. For this reason wheels are used both to enhance welfare and to create models of exercise. However, many designs of running wheel are used. This makes between-study comparisons difficult, as this variability could potentially affect the amount, pattern, and/or intensity of running behaviour, and thence the wheels' effects on welfare and exercise-related changes in anatomy and physiology. This study therefore evaluated two commercially available models, chosen because safe for group-housed mice: Bio Serv®'s "fast-trac" wheel combo and Ware Manufacturing Inc.'s stainless steel mesh 5″ upright wheel. Working with a total of three hundred and fifty one female C57BL/6, DBA/2 and BALB/c mice, we assessed these wheels' relative utilization by mice when access was free; the strength of motivation for each wheel-type when access required crossing an electrified grid; and the impact each wheel had on mouse well-being (inferred from acoustic startle responses and neophobia) and exercise-related anatomical changes (BMI; heart and hind limb masses). Mice ran more on the "fast-trac" wheel regardless of whether both wheel-types were available at once, or only if one was present. In terms of motivation, subjects required to work to access a single wheel worked equally hard for both wheel-types (even if locked and thus not useable for running), but if provided with one working wheel for free and the other type of wheel (again unlocked) accessible via crossing the electrified grid, the "fast-trac" wheel emerged as more motivating, as the Maximum Price Paid for the Ware metal wheel was lower than that paid for the "fast-trac" plastic wheel, at least for C57BL/6s and DBA/2s. No deleterious consequences were noted with either wheel in terms of health and welfare, but only mice with plastic wheels developed significantly larger hearts and hind limbs than control animals with locked wheels. Thus, where differences emerged, Bio Serv®'s "fast-trac" wheel combos appeared to better meet the aims of exercise provision than Ware Manufacturing's steel upright wheels. Copyright © 2018 Elsevier Inc. All rights reserved.

NASA Planetary Rover Program

NASA Technical Reports Server (NTRS)

Lavery, David; Bedard, Roger J., Jr.

1991-01-01

The NASA Planetary Rover Project was initiated in 1989. The emphasis of the work to date has been on development of autonomous navigation technology within the context of a high mobility wheeled vehicle at the JPL and an innovative legged locomotion concept at Carnegie Mellon University. The status and accomplishments of these two efforts are discussed. First, however, background information is given on the three rover types required for the Space Exploration Initiative (SEI) whose objective is a manned mission to Mars.

Assistive devices alter gait patterns in Parkinson disease: advantages of the four-wheeled walker.

PubMed

Kegelmeyer, Deb A; Parthasarathy, Sowmya; Kostyk, Sandra K; White, Susan E; Kloos, Anne D

2013-05-01

Gait abnormalities are a hallmark of Parkinson's disease (PD) and contribute to fall risk. Therapy and exercise are often encouraged to increase mobility and decrease falls. As disease symptoms progress, assistive devices are often prescribed. There are no guidelines for choosing appropriate ambulatory devices. This unique study systematically examined the impact of a broad range of assistive devices on gait measures during walking in both a straight path and around obstacles in individuals with PD. Quantitative gait measures, including velocity, stride length, percent swing and double support time, and coefficients of variation were assessed in 27 individuals with PD with or without one of six different devices including canes, standard and wheeled walkers (two, four or U-Step). Data were collected using the GAITRite and on a figure-of-eight course. All devices, with the exception of four-wheeled and U-Step walkers significantly decreased gait velocity. The four-wheeled walker resulted in less variability in gait measures and had less impact on spontaneous unassisted gait patterns. The U-Step walker exhibited the highest variability across all parameters followed by the two-wheeled and standard walkers. Higher variability has been correlated with increased falls. Though subjects performed better on a figure-of-eight course using either the four-wheeled or the U-Step walker, the four-wheeled walker resulted in the most consistent improvement in overall gait variables. Laser light use on a U-Step walker did not improve gait measures or safety in figure-of-eight compared to other devices. Of the devices tested, the four-wheeled-walker offered the most consistent advantages for improving mobility and safety. Copyright © 2012 Elsevier B.V. All rights reserved.

UT Biomedical Informatics Lab (BMIL) probability wheel

NASA Astrophysics Data System (ADS)

Huang, Sheng-Cheng; Lee, Sara; Wang, Allen; Cantor, Scott B.; Sun, Clement; Fan, Kaili; Reece, Gregory P.; Kim, Min Soon; Markey, Mia K.

A probability wheel app is intended to facilitate communication between two people, an "investigator" and a "participant", about uncertainties inherent in decision-making. Traditionally, a probability wheel is a mechanical prop with two colored slices. A user adjusts the sizes of the slices to indicate the relative value of the probabilities assigned to them. A probability wheel can improve the adjustment process and attenuate the effect of anchoring bias when it is used to estimate or communicate probabilities of outcomes. The goal of this work was to develop a mobile application of the probability wheel that is portable, easily available, and more versatile. We provide a motivating example from medical decision-making, but the tool is widely applicable for researchers in the decision sciences.

Behavior generation strategy of artificial behavioral system by self-learning paradigm for autonomous robot tasks

NASA Astrophysics Data System (ADS)

Dağlarli, Evren; Temeltaş, Hakan

2008-04-01

In this study, behavior generation and self-learning paradigms are investigated for the real-time applications of multi-goal mobile robot tasks. The method is capable to generate new behaviors and it combines them in order to achieve multi goal tasks. The proposed method is composed from three layers: Behavior Generating Module, Coordination Level and Emotion -Motivation Level. Last two levels use Hidden Markov models to manage dynamical structure of behaviors. The kinematics and dynamic model of the mobile robot with non-holonomic constraints are considered in the behavior based control architecture. The proposed method is tested on a four-wheel driven and four-wheel steered mobile robot with constraints in simulation environment and results are obtained successfully.

Design of a high-mobility multi-terrain robot based on eccentric paddle mechanism.

PubMed

Sun, Yi; Yang, Yang; Ma, Shugen; Pu, Huayan

Gaining high mobility on versatile terrains is a crucial target for designing a mobile robot toward tasks such as search and rescue, scientific exploration, and environment monitoring. Inspired by dextrous limb motion of animals, a novel form of locomotion has been established in our previous study, by proposing an eccentric paddle mechanism (ePaddle) for integrating paddling motion into a traditional wheeled mechanism. In this paper, prototypes of an ePaddle mechanism and an ePaddle-based quadruped robot are presented. Several locomotion modes, including wheeled rolling, legged crawling, legged race-walking, rotational paddling, oscillating paddling, and paddle-aided rolling, are experimentally verified on testbeds with fabricated prototypes. Experimental results confirm that paddle's motion is useful in all the locomotion modes.

Compliant-linkage kinematic design for multi-degree-of-freedom mobile robots

NASA Astrophysics Data System (ADS)

Borenstein, Johann

1993-05-01

Multi-degree-of-freedom (MDOF) vehicles have many potential advantages over conventional (i.e., 2-DOF) vehicles. For example, MDOF vehicles can travel sideways and they can negotiate tight turns more easily. In addition, some MDOF designs provide better payload capability, better traction, and improved static and dynamic stability. However, MDOF vehicles with more than three degrees-of-freedom are difficult to control because of their overconstrained nature. These difficulties translate into severe wheel slippage or jerky motion under certain driving conditions. In the past, these problems limited the use of MDOF vehicles to applications where the vehicle would follow a guide-wire, which would correct wheel slippage and control errors. By contrast, autonomous or semi-autonomous mobile robots usually rely on dead-reckoning between periodic absolute position updates and their performance is diminished by excessive wheel slippage. This paper introduces a new concept in the kinematic design of MDOF vehicles. This concept is based on the provision of a compliant linkage between drive wheels or drive axles. Simulation results indicate that compliant linkage allows to overcome the control problems found in conventional MDOF vehicles and reduces the amount of wheel slippage to the same level (or less) than the amount of slippage found on a comparable 2-DOF vehicle.

The meaning ascribed to wheeled mobility devices by individuals who use wheelchairs and scooters: a metasynthesis.

PubMed

Ripat, Jacquie; Verdonck, Michele; Carter, Roger Jaffrey

2018-04-01

To synthesize qualitative study findings on the meaning ascribed to wheelchairs and wheeled mobility devices (WMD) by WMD users. Bibliographic databases were systematically searched up to January 2015 to identify relevant papers. Reviewers selected studies, assessed methodological quality and thematically synthesized findings using a metasynthesis process described by Thomas and Harden (2008). Twenty articles were included. Four descriptive themes emerged: physical environment interaction; sociocultural experiences; participation in activities and occupations; and WMD-self relationship. WMD use was found to be a complex experience that can fluctuate through interaction with aspects of the environment and opportunities for participation. The analytic theme, dynamic duality of WMD experience, addressed the simultaneous enabling and disabling aspects of WMD use. Metasyntheses enable researchers to gain a deeper understanding of issues by examining findings across studies. Findings of this study provide a framework for understanding the complexity of WMD use. The framework has practical applications for clinicians and users of WMD in understanding the experience of WMD to be neither singular nor static. Implications for Rehabilitation The meaning of wheeled mobility device (WMD) use is dynamically influenced by the environment and opportunities afforded for occupational and social participation. A duality of experiences can emerge for WMD users, where wheeled mobility use can be at the same time positive and negative, based on the interaction with the environment. Clinicians need to determine the meaning that each individual user ascribes to the WMD, and to consider how that meaning may change over time. By understanding the meaning ascribed to WMD use by individuals, clinicians can be better prepared to work with the WMD users to address negative reinforcers of the experience in physical and sociocultural environments as well as highlighting the positive experiences.

Application of the Quality Functional Deployment Method in Mobility Aid Securement System Design

DOT National Transportation Integrated Search

1992-12-01

The Independent Locking Securement System Project (ILS System Project) is a : successful attempt to respond to the transportation community's need for a : "universal" securement/restraint system that will accommodate most wheeled : mobility aids, inc...

Control of an automated mobile manipulator using artificial immune system

NASA Astrophysics Data System (ADS)

Deepak, B. B. V. L.; Parhi, Dayal R.

2016-03-01

This paper addresses the coordination and control of a wheeled mobile manipulator (WMM) using artificial immune system. The aim of the developed methodology is to navigate the system autonomously and transport jobs and tools in manufacturing environments. This study integrates the kinematic structures of a four-axis manipulator and a differential wheeled mobile platform. The motion of the developed WMM is controlled by the complete system of parametric equation in terms of joint velocities and makes the robot to follow desired trajectories by the manipulator and platform within its workspace. The developed robot system performs its action intelligently according to the sensed environmental criteria within its search space. To verify the effectiveness of the proposed immune-based motion planner for WMM, simulations as well as experimental results are presented in various unknown environments.

Nuclear Hell On Wheels Examining The Need For A Mobile ICBM

DTIC Science & Technology

2015-02-17

www.defenseone.com/ideas/2014/11/last-thing- us-needs-are-mobile-nuclear-missiles/98828/?oref=d- skybox (accessed 28 Nov 2014) 4 Department of Defense...last-thing-us-needs- are-mobile-nuclear-missiles/98828/?oref=d- skybox (accessed 28 Nov 2014) Craig, Campbell. Destroying the Village: Eisenhower and

Lightweight rovers for Mars science exploration and sample return

NASA Astrophysics Data System (ADS)

Schenker, Paul S.; Sword, Lee F.; Ganino, A. J.; Bickler, Donald B.; Hickey, G. S.; Brown, D. K.; Baumgartner, Eric T.; Matthies, Larry H.; Wilcox, Brian H.; Balch, T.; Aghazarian, H.; Garrett, M. S.

1997-09-01

We report on the development of new mobile robots for Mars exploration missions. These 'lightweight survivable rover (LSR)' systems are of potential interest to both space and terrestrial applications, and are distinguished from more conventional designs by their use of new composite materials, collapsible running gear, integrated thermal-structural chassis, and other mechanical features enabling improved mobility and environmental robustness at reduced mass, volume, and power. Our first demonstrated such rover architecture, LSR-1, introduces running gear based on 2D composite struts and 3D machined composite joints, a novel collapsible hybrid composite-aluminum wheel design, a unit-body structural- thermal chassis with improved internal temperature isolation and stabilization, and a spot-pushbroom laser/CCD sensor enabling accurate, fast hazard detection and terrain mapping. LSR-1 is an approximately .7 $MIL 1.0 meter(Lambda) 2(W X L) footprint six-wheel (20 cm dia.) rocker-bogie geometry vehicle of approximately 30 cm ground clearance, weighing only 7 kilograms with an onboard .3 kilogram multi-spectral imager and spectroscopic photometer. By comparison, NASA/JPL's recently flown Mars Pathfinder rover Sojourner is an 11+ kilogram flight experiment (carrying a 1 kg APXS instrument) having approximately .45 X .6 meter(Lambda) 2(WXL) footprint and 15 cm ground clearance, and about half the warm electronics enclosure (WEE) volume with twice the diurnal temperature swing (-40 to +40 degrees Celsius) of LSR- 1 in nominal Mars environments. We are also developing a new, smaller 5 kilogram class LSR-type vehicle for Mars sample return -- the travel to, localization of, pick-up, and transport back to an Earth return ascent vehicle of a sample cache collected by earlier science missions. This sample retrieval rover R&D prototype has a completely collapsible mobility system enabling rover stowage to approximately 25% operational volume, as well an actively articulated axle, allowing changeable pose of the wheel strut geometry for improved transverse and manipulation characteristics.

29 CFR 1910.211 - Definitions.

Code of Federal Regulations, 2012 CFR

2012-07-01

..., and hole size dimensions. Both types are reinforced, organic bonded wheels having offset hubs which..., thickness, and hole size dimensions. They are reinforced, organic bonded, offset hub type wheels, usually 16... following abrasive wheel machinery terms shall have the meanings prescribed in this paragraph. (1) Type 1...

29 CFR 1910.211 - Definitions.

Code of Federal Regulations, 2013 CFR

2013-07-01

..., and hole size dimensions. Both types are reinforced, organic bonded wheels having offset hubs which..., thickness, and hole size dimensions. They are reinforced, organic bonded, offset hub type wheels, usually 16... following abrasive wheel machinery terms shall have the meanings prescribed in this paragraph. (1) Type 1...

Planter closing wheel effects on cotton emergence in a conservation tillage system

USDA-ARS?s Scientific Manuscript database

Closing wheels on a row crop planter help provide good seed-soil contact during planting and can influence emergence and crop stand. Various types of closing wheels are available to producers for use on planters. Seven closing wheel types were used on a row crop planter planting cotton in a conser...

Development of an Independent Locking Securement System for Mobility Aids on Public Transportation Vehicles

DOT National Transportation Integrated Search

1992-12-01

The Independent Locking Securement System Project (ILS System Project) is a : successful attempt to respond to the transportation community's need for a : "universal" securement/restraint system that will accommodate most wheeled : mobility aids, inc...

Kinematic evaluation of mobile robotic platforms for overground gait neurorehabilitation

NASA Astrophysics Data System (ADS)

Alias, N. Akmal; Huq, M. Saiful; Ibrahim, B. S. K. K.; Omar, Rosli

2017-09-01

Gait assistive devices offer a great solution to the walking re-education which reduce patients theoretical limit by aiding the anatomical joints to be in line with the rehabilitation session. Overground gait training, which is differs significantly from body-weight supported treadmill training in many aspects, essentially consists of a mobile robotic base to support the subject securely (usually with overhead harness) while its motion and orientation is controlled seamlessly to facilitate subjects free movement. In this study, efforts have been made for evaluation of both holonomic and nonholonomic drives, the outcome of which may constitute the primarily results to the effective approach in designing a robotic platform for the mobile rehabilitation robot. The sets of kinematic equations are derived using typical geometries of two different drives. The results indicate that omnidirectional mecanum wheel platform is capable for more sophisticated discipline. Although the differential drive platform happens to be more simple and easy to construct, but it is less desirable as it has limited number of motions applicable to the system. The omnidirectional robot consisting of mecanum wheels, which is classified as holonomic is potentially the best solution in terms of its capability to move in arbitrary direction without concerning the changing of wheel's direction.

A sub-target approach to the kinodynamic motion control of a wheeled mobile robot

NASA Astrophysics Data System (ADS)

Motonaka, Kimiko; Watanabe, Keigo; Maeyama, Shoichi

2018-02-01

A mobile robot with two independently driven wheels is popular, but it is difficult to stabilize it by a continuous controller with a constant gain, due to its nonholonomic property. It is guaranteed that a nonholonomic controlled object can always be converged to an arbitrary point using a switching control method or a quasi-continuous control method based on an invariant manifold in a chained form. From this, the authors already proposed a kinodynamic controller to converge the states of such a two-wheeled mobile robot to the arbitrary target position while avoiding obstacles, by combining the control based on the invariant manifold and the harmonic potential field (HPF). On the other hand, it was confirmed in the previous research that there is a case that the robot cannot avoid the obstacle because there is no enough space to converge the current state to the target state. In this paper, we propose a method that divides the final target position into some sub-target positions and moves the robot step by step, and it is confirmed by the simulation that the robot can converge to the target position while avoiding obstacles using the proposed method.

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

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.

Applied design methodology for lunar rover elastic wheel

NASA Astrophysics Data System (ADS)

Cardile, Diego; Viola, Nicole; Chiesa, Sergio; Rougier, Alessandro

2012-12-01

In recent years an increasing interest in the Moon surface operations has been experienced. In the future robotic and manned missions of Moon surface exploration will be fundamental in order to lay the groundwork for more ambitious space exploration programs. Surface mobility systems will be the key elements to ensure an efficient and safe Moon exploration. Future lunar rovers are likely to be heavier and able to travel longer distances than the previously developed Moon rover systems. The Lunar Roving Vehicle (LRV) is the only manned rover, which has so far been launched and used on the Moon surface. Its mobility system included flexible wheels that cannot be scaled to the heavier and longer range vehicles. Thus the previously developed wheels are likely not to be suitable for the new larger vehicles. Taking all these considerations into account, on the basis of the system requirements and assumptions, several wheel concepts have been discussed and evaluated through a trade-off analysis. Semi-empirical equations have been utilized to predict the wheel geometrical characteristics, as well as to estimate the motion resistances and the ability of the system to generate thrust. A numerical model has also been implemented, in order to define more into the details the whole wheel design, in terms of wheel geometry and physical properties. As a result of the trade-off analysis, the ellipse wheel concept has shown the best behavior in terms of stiffness, mass budget and dynamic performance. The results presented in the paper have been obtained in cooperation with Thales Alenia Space-Italy and Sicme motori, in the framework of a regional program called STEPS . STEPS-Sistemi e Tecnologie per l'EsPlorazione Spaziale is a research project co-financed by Piedmont Region and firms and universities of the Piedmont Aerospace District in the ambit of the P.O.R-F.E.S.R. 2007-2013 program.

Saturn Apollo Program

NASA Image and Video Library

1970-03-20

Under the direction of Marshall Space Flight Center (MSFC), the Lunar Roving Vehicle (LRV) was designed to allow Apollo astronauts a greater range of mobility during lunar exploration missions. During the development process, LRV prototype wheels underwent soil tests in building 4481 at Marshall Space Flight Center (MSFC). Pictured from left to right are the wheels for: LRV, Bendix Corporation, Local Scientific Survey Module (LSSM), and Grumman Industries.

Thermal signature characteristics of vehicle/terrain interaction disturbances: implications for battlefield vehicle classification.

PubMed

Eastes, John W; Mason, George L; Kusinger, Alan E

2004-05-01

Thermal emissivity spectra (8-14 microm) of track impressions/background were determined in conjunction with operation of six military vehicle types, T-72 and M1 Tanks, an M2 Bradley Fighting Vehicle, a 5-ton truck, a D7 tractor, and a High Mobility Multipurpose Wheeled Vehicle (HMMWV), over diverse soil surfaces to determine if vehicle type could be related to track thermal signatures. Results suggest soil compaction and fragmentation/pulverization are primary parameters affecting track signatures and that soil and vehicle/terrain-contact type determine which parameter dominates. Steel-tracked vehicles exert relatively low ground-contact pressure but tend to fragment/pulverize soil more so than do rubber-tired vehicles, which tend mainly to compact. In quartz-rich, lean clay soil tracked vehicles produced impressions with spectral contrast of the quartz reststrahlen features decreased from that of the background. At the same time, 5-ton truck tracks exhibited increased contrast on the same surface, suggesting that steel tracks fragmented soil while rubber tires mainly produced compaction. The structure of materials such as sand and moist clay-rich river sediment makes them less subject to further fragmentation/pulverization; thus, compaction was the main factor affecting signatures in these media, and both tracked and wheeled vehicles created impressions with increased spectral contrast on these surfaces. These results suggest that remotely sensed thermal signatures could differentiate tracked and wheeled vehicles on terrain in many areas of the world of strategic interest. Significant applications include distinguishing visually/spectrally identical lightweight decoys from actual threat vehicles.

Feasibility of the Enhancing Participation In the Community by improving Wheelchair Skills (EPIC Wheels) program: study protocol for a randomized controlled trial.

PubMed

Giesbrecht, Edward M; Miller, William C; Eng, Janice J; Mitchell, Ian M; Woodgate, Roberta L; Goldsmith, Charles H

2013-10-24

Many older adults rely on a manual wheelchair for mobility but typically receive little, if any, training on how to use their wheelchair effectively and independently. Standardized skill training is an effective intervention, but limited access to clinician trainers is a substantive barrier. Enhancing Participation in the Community by Improving Wheelchair Skills (EPIC Wheels) is a 1-month monitored home training program for improving mobility skills in older novice manual wheelchair users, integrating principles from andragogy and social cognitive theory. The purpose of this study is to determine whether feasibility indicators and primary clinical outcome measures of the EPIC Wheels program are sufficiently robust to justify conducting a subsequent multi-site randomized controlled trial. A 2 × 2 factorial randomized controlled trial at two sites will compare improvement in wheelchair mobility skills between an EPIC Wheels treatment group and a computer-game control group, with additional wheelchair use introduced as a second factor. A total of 40 community-dwelling manual wheelchair users at least 55 years old and living in two Canadian metropolitan cities (n = 20 × 2) will be recruited. Feasibility indicators related to study process, resources, management, and treatment issues will be collected during data collection and at the end of the study period, and evaluated against proposed criteria. Clinical outcome measures will be collected at baseline (pre-randomization) and post-intervention. The primary clinical outcome measure is wheelchair skill capacity, as determined by the Wheelchair Skills Test, version 4.1. Secondary clinical outcome measures include wheelchair skill safety, satisfaction with performance, wheelchair confidence, life-space mobility, divided-attention, and health-related quality of life. The EPIC Wheels training program offers several innovative features. The convenient, portable, economical, and adaptable tablet-based, home program model for wheelchair skills training has great potential for clinical uptake and opportunity for future enhancements. Theory-driven design can foster learning and adherence for older adults. Establishing the feasibility of the study protocol and estimating effect size for the primary clinical outcome measure will be used to develop a multi-site randomized controlled trial to test the guiding hypotheses. Clinical Trials NCT01740635.

The attentional demands of ambulating with an assistive device in older adults with Alzheimer's disease.

PubMed

Muir-Hunter, S W; Montero-Odasso, M

2017-05-01

Ambulation with a mobility aid is a unique real-life situation of multi-tasking. These simultaneous motor tasks place increased demands on executive function in healthy young and older adults, but the demands have not been evaluated in people with Alzheimer's disease (AD). Mobility problems are common among adults with AD, leading to provision of a mobility aid to optimize independent activity. The study objectives were: (i) to determine the dual-task cost (DTC) associated with the use of a mobility aid in straight and complex path walking, and (ii) to evaluate the association between executive function and ambulation with a mobility aid in older adults with AD and age-sex matched cognitively normal controls. Fourteen people (mean age±SD, 72.6±9.9years) with a diagnosis of probable AD (MMSE range 12-25) and controls (mean age±SD, 72.9±9.5) walked at a self-selected pace and using a 4-wheeled walker in a 6m straight path and a Figure of 8 Test. Ambulation with the walker in a straight path produced a low DTC that was not different between the groups. Ambulation with the 4-wheeled walker in the complex path produced a significantly different DTC in the group with AD at -38.1±23.5% compared to -19.7±21.4% (p=0.041). Lower scores on executive function were associated with longer times across test conditions. Ambulation with a 4-wheeled walker, in particular maneuvering around obstacles, requires greater attentional costs in dementia. Future research should explore the timing for safely introducing mobility aids in AD and the role of improving executive function. Copyright © 2017 Elsevier B.V. All rights reserved.

Mid-sized omnidirectional robot with hydraulic drive and steering

NASA Astrophysics Data System (ADS)

Wood, Carl G.; Perry, Trent; Cook, Douglas; Maxfield, Russell; Davidson, Morgan E.

2003-09-01

Through funding from the US Army-Tank-Automotive and Armaments Command's (TACOM) Intelligent Mobility Program, Utah State University's (USU) Center for Self-Organizing and Intelligent Systems (CSOIS) has developed the T-series of omni-directional robots based on the USU omni-directional vehicle (ODV) technology. The ODV provides independent computer control of steering and drive in a single wheel assembly. By putting multiple omni-directional (OD) wheels on a chassis, a vehicle is capable of uncoupled translational and rotational motion. Previous robots in the series, the T1, T2, T3, ODIS, ODIS-T, and ODIS-S have all used OD wheels based on electric motors. The T4 weighs approximately 1400 lbs and features a 4-wheel drive wheel configuration. Each wheel assembly consists of a hydraulic drive motor and a hydraulic steering motor. A gasoline engine is used to power both the hydraulic and electrical systems. The paper presents an overview of the mechanical design of the vehicle as well as potential uses of this technology in fielded systems.

Design and manufacture of wheels for a dual-mode (manned - automatic) lunar surface roving vehicle. Volume 2: Proposed test plan

NASA Technical Reports Server (NTRS)

1970-01-01

A developmental test plan for the wheel and wheel drive assembly of the dual-mode (manned/automated) lunar surface roving vehicle is presented. The tests cover performance, as well as critical environmental characteristics. Insofar as practical, the environmental conditions imposed will be in the sequence expected during the hardware's life from storage through the lunar mission. Test procedures are described for static load deflection and endurance tests. Soft soil tests to determine mobility characteristics including drawbar-pull and thrust vs slip, and motion resistance for various wheel loads are also discussed. Test designs for both ambient and thermal vacuum conditions are described. Facility, transducer, and instrumentation requirements are outlined.

Dynamic modeling and mobility analysis of the transforming roving-rolling explorer (TRREx) as it Traverses Rugged Martian Terrain

NASA Astrophysics Data System (ADS)

Edwin, Lionel E.; Mazzoleni, Andre P.

2016-03-01

All planetary surface exploration missions thus far have employed traditional rovers with a rocker-bogie suspension. These rovers can navigate moderately rough and flat terrain, but are not designed to traverse rugged terrain with steep slopes. The fact is, however, that the most scientifically interesting missions require exploration platforms with capabilities for navigating such types of rugged terrain. This issue motivates the development of new kinds of rovers that take advantage of the latest advances in robotic technologies to traverse rugged terrain efficiently. This work analyzes one such rover concept called the Transforming Roving-Rolling Explorer (TRREx) that is principally aimed at addressing the above issue. Biologically inspired by the way the armadillo curls up into a ball when threatened, and the way the golden wheel spider uses the dynamic advantages of a sphere to roll down hills when escaping danger, the TRREx rover can traverse like a traditional 6-wheeled rover over conventional terrain, but can also transform itself into a sphere, when necessary, to travel down steep inclines, or navigate rough terrain. This paper investigates the mobility of the TRREx when it is in its rolling mode, i.e. when it is a sphere and can steer itself through actuations that shift its center of mass to achieve the desired direction of roll. A mathematical model describing the dynamics of the rover in this spherical configuration is presented, and actuated rolling is demonstrated through computer simulation. Parametric analyzes that investigate the rover's mobility as a function of its design parameters are also presented. This work highlights the contribution of the spherical rolling mode to the enhanced mobility of the TRREx rover and how it could enable challenging surface exploration missions in the future.

29 CFR 1928.52 - Protective frames for wheel-type agricultural tractors-test procedures and performance requirements.

Code of Federal Regulations, 2011 CFR

2011-07-01

... the same design shall be used during each such test. (iii) Instantaneous deflection shall be measured... 29 Labor 9 2011-07-01 2011-07-01 false Protective frames for wheel-type agricultural tractors-test... for wheel-type agricultural tractors—test procedures and performance requirements. (a) Purpose. The...

29 CFR 1928.52 - Protective frames for wheel-type agricultural tractors-test procedures and performance requirements.

Code of Federal Regulations, 2010 CFR

2010-07-01

... the same design shall be used during each such test. (iii) Instantaneous deflection shall be measured... 29 Labor 9 2010-07-01 2010-07-01 false Protective frames for wheel-type agricultural tractors-test... for wheel-type agricultural tractors—test procedures and performance requirements. (a) Purpose. The...

29 CFR 1928.52 - Protective frames for wheel-type agricultural tractors-test procedures and performance requirements.

Code of Federal Regulations, 2013 CFR

2013-07-01

... the same design shall be used during each such test. (iii) Instantaneous deflection shall be measured... 29 Labor 9 2013-07-01 2013-07-01 false Protective frames for wheel-type agricultural tractors-test... for wheel-type agricultural tractors—test procedures and performance requirements. (a) Purpose. The...

29 CFR 1928.52 - Protective frames for wheel-type agricultural tractors-test procedures and performance requirements.

Code of Federal Regulations, 2012 CFR

2012-07-01

... the same design shall be used during each such test. (iii) Instantaneous deflection shall be measured... 29 Labor 9 2012-07-01 2012-07-01 false Protective frames for wheel-type agricultural tractors-test... for wheel-type agricultural tractors—test procedures and performance requirements. (a) Purpose. The...

29 CFR 1926.303 - Abrasive wheels and tools.

Code of Federal Regulations, 2011 CFR

2011-07-01

... distance not to exceed one-eighth inch from the surface of the wheel. (3) Cup type wheels used for external grinding shall be protected by either a revolving cup guard or a band type guard in accordance with the...

29 CFR 1926.303 - Abrasive wheels and tools.

Code of Federal Regulations, 2010 CFR

2010-07-01

... distance not to exceed one-eighth inch from the surface of the wheel. (3) Cup type wheels used for external grinding shall be protected by either a revolving cup guard or a band type guard in accordance with the...

29 CFR 1915.134 - Abrasive wheels.

Code of Federal Regulations, 2011 CFR

2011-07-01

... shall be kept a distance not to exceed 1/8 inch from the surface of the wheel. (c) Cup type wheels used for external grinding shall be protected by either a revolving cup guard or a band type guard in...

29 CFR 1915.134 - Abrasive wheels.

Code of Federal Regulations, 2010 CFR

2010-07-01

... shall be kept a distance not to exceed 1/8 inch from the surface of the wheel. (c) Cup type wheels used for external grinding shall be protected by either a revolving cup guard or a band type guard in...

Determining Wheel-Soil Interaction Loads Using a Meshfree Finite Element Approach Assisting Future Missions with Rover Wheel Design

NASA Technical Reports Server (NTRS)

Contreras, Michael T.; Peng, Chia-Yen; Wang, Dongdong; Chen, Jiun-Shyan

2012-01-01

A wheel experiencing sinkage and slippage events poses a high risk to rover missions as evidenced by recent mobility challenges on the Mars Exploration Rover (MER) project. Because several factors contribute to wheel sinkage and slippage conditions such as soil composition, large deformation soil behavior, wheel geometry, nonlinear contact forces, terrain irregularity, etc., there are significant benefits to modeling these events to a sufficient degree of complexity. For the purposes of modeling wheel sinkage and slippage at an engineering scale, meshfree finite element approaches enable simulations that capture sufficient detail of wheel-soil interaction while remaining computationally feasible. This study demonstrates some of the large deformation modeling capability of meshfree methods and the realistic solutions obtained by accounting for the soil material properties. A benchmark wheel-soil interaction problem is developed and analyzed using a specific class of meshfree methods called Reproducing Kernel Particle Method (RKPM). The benchmark problem is also analyzed using a commercially available finite element approach with Lagrangian meshing for comparison. RKPM results are comparable to classical pressure-sinkage terramechanics relationships proposed by Bekker-Wong. Pending experimental calibration by future work, the meshfree modeling technique will be a viable simulation tool for trade studies assisting rover wheel design.

Northwest Manufacturing Initiative

DTIC Science & Technology

2013-08-31

to automobiles and wind turbine blades [1-4]. The difficulty with incorporating composites lies in joining material sections together. Composite...marine and wind turbine structures [1, 23]. All the material systems consist of [M/90/0] lamina, which are a combination of one layer of chopped...completely new control system (including software interfaces) were developed and used to build both 2 wheel and 4 wheel driven mobile, wireless robots

Modern mechanisms make manless Martian mission mobile: Spin-off spells stairclimbing self-sufficiency for earthbound handicapped

NASA Technical Reports Server (NTRS)

Sandor, G. N.; Hassel, D. R.; Marino, P. F.

1975-01-01

Concepts were developed for three wheel chairs from progressively improving designs of a proposed unmanned roving vehicle for the surface exploration of Mars; as a spin-off, a concept for a stair-climbing wheel chair was generated. The mechanisms employed in these are described. The Mars mission is envisioned using the booster rockets and aeroshell of the Viking missions.

Characterizing Wheel-Soil Interaction Loads Using Meshfree Finite Element Methods: A Sensitivity Analysis for Design Trade Studies

NASA Technical Reports Server (NTRS)

Contreras, Michael T.; Trease, Brian P.; Bojanowski, Cezary; Kulakx, Ronald F.

2013-01-01

A wheel experiencing sinkage and slippage events poses a high risk to planetary rover missions as evidenced by the mobility challenges endured by the Mars Exploration Rover (MER) project. Current wheel design practice utilizes loads derived from a series of events in the life cycle of the rover which do not include (1) failure metrics related to wheel sinkage and slippage and (2) performance trade-offs based on grouser placement/orientation. Wheel designs are rigorously tested experimentally through a variety of drive scenarios and simulated soil environments; however, a robust simulation capability is still in development due to myriad of complex interaction phenomena that contribute to wheel sinkage and slippage conditions such as soil composition, large deformation soil behavior, wheel geometry, nonlinear contact forces, terrain irregularity, etc. For the purposes of modeling wheel sinkage and slippage at an engineering scale, meshfree nite element approaches enable simulations that capture su cient detail of wheel-soil interaction while remaining computationally feasible. This study implements the JPL wheel-soil benchmark problem in the commercial code environment utilizing the large deformation modeling capability of Smooth Particle Hydrodynamics (SPH) meshfree methods. The nominal, benchmark wheel-soil interaction model that produces numerically stable and physically realistic results is presented and simulations are shown for both wheel traverse and wheel sinkage cases. A sensitivity analysis developing the capability and framework for future ight applications is conducted to illustrate the importance of perturbations to critical material properties and parameters. Implementation of the proposed soil-wheel interaction simulation capability and associated sensitivity framework has the potential to reduce experimentation cost and improve the early stage wheel design proce

A drive system to add standing mobility to a manual standing wheelchair.

PubMed

Nickel, Eric; Hansen, Andrew; Pearlman, Jonathan; Goldish, Gary

2016-05-16

Current manual standing wheelchairs are not mobile in the standing position. The addition of standing mobility may lead to improved health and function for the user and may increase utilization of standing wheelchairs. In this project, a chain drive system was fitted to a manual standing wheelchair, adding mobility in the standing position. The hand rims are accessible from both seated and standing positions. The prototype uses 16-inch drive wheels in front with casters in the rear. Additional anterior casters are elevated when seated for navigating obstacles and then descend when standing to create a six-wheeled base with extended anterior support. Stability testing shows the center of pressure remains within the base of support when leaning to the sides or front in both seated and standing positions. Four veterans with spinal cord injury provided feedback on the design and reported that mobility during standing was very important or extremely important to them. The veterans liked the perceived stability and mobility of the prototype and provided feedback for future refinements. For example, reducing the overall width (width from hand rim to hand rim) and weight could make this system more functional for users.

PD-like controller for delayed bilateral teleoperation of wheeled robots

NASA Astrophysics Data System (ADS)

Slawiñski, E.; Mut, V.; Santiago, D.

2016-08-01

This paper proposes a proportional derivative (PD)-like controller applied to the delayed bilateral teleoperation of wheeled robots with force feedback in face of asymmetric and varying-time delays. In contrast to bilateral teleoperation of manipulator robots, in these systems, there is a mismatch between the models of the master and slave (mobile robot), problem that is approached in this work, where the system stability is analysed. From this study, it is possible to infer the control parameters, depending on the time delay, necessary to assure stability. Finally, the performance of the delayed teleoperation system is evaluated through tests where a human operator drives a 3D simulator as well as a mobile robot for pushing objects.

Cross-coupled control for all-terrain rovers.

PubMed

Reina, Giulio

2013-01-08

Mobile robots are increasingly being used in challenging outdoor environments for applications that include construction, mining, agriculture, military and planetary exploration. In order to accomplish the planned task, it is critical that the motion control system ensure accuracy and robustness. The achievement of high performance on rough terrain is tightly connected with the minimization of vehicle-terrain dynamics effects such as slipping and skidding. This paper presents a cross-coupled controller for a 4-wheel-drive/4-wheel-steer robot, which optimizes the wheel motors' control algorithm to reduce synchronization errors that would otherwise result in wheel slip with conventional controllers. Experimental results, obtained with an all-terrain rover operating on agricultural terrain, are presented to validate the system. It is shown that the proposed approach is effective in reducing slippage and vehicle posture errors.

Path-following control of wheeled planetary exploration robots moving on deformable rough terrain.

PubMed

Ding, Liang; Gao, Hai-bo; Deng, Zong-quan; Li, Zhijun; Xia, Ke-rui; Duan, Guang-ren

2014-01-01

The control of planetary rovers, which are high performance mobile robots that move on deformable rough terrain, is a challenging problem. Taking lateral skid into account, this paper presents a rough terrain model and nonholonomic kinematics model for planetary rovers. An approach is proposed in which the reference path is generated according to the planned path by combining look-ahead distance and path updating distance on the basis of the carrot following method. A path-following strategy for wheeled planetary exploration robots incorporating slip compensation is designed. Simulation results of a four-wheeled robot on deformable rough terrain verify that it can be controlled to follow a planned path with good precision, despite the fact that the wheels will obviously skid and slip.

Path-Following Control of Wheeled Planetary Exploration Robots Moving on Deformable Rough Terrain

PubMed Central

Ding, Liang; Gao, Hai-bo; Deng, Zong-quan; Li, Zhijun; Xia, Ke-rui; Duan, Guang-ren

2014-01-01

The control of planetary rovers, which are high performance mobile robots that move on deformable rough terrain, is a challenging problem. Taking lateral skid into account, this paper presents a rough terrain model and nonholonomic kinematics model for planetary rovers. An approach is proposed in which the reference path is generated according to the planned path by combining look-ahead distance and path updating distance on the basis of the carrot following method. A path-following strategy for wheeled planetary exploration robots incorporating slip compensation is designed. Simulation results of a four-wheeled robot on deformable rough terrain verify that it can be controlled to follow a planned path with good precision, despite the fact that the wheels will obviously skid and slip. PMID:24790582

Vehicle Mobility Assessment for Project Wheels Study Group

DTIC Science & Technology

1972-07-01

cash savings p’Asible through the elimination of special military automotive features, such as front-wheel 1 Idrive , or the use of commercial vehicles...E12. (12) off-,,,d mobiliY profile 4x4 0ruck, c 2Z4< 20 ,ernn It Iot "- III IIIII III I I I IIII A%. West Germany 0A * s ps ArizonazD • Ř’.. • D

Rover Wheel-Actuated Tool Interface

NASA Technical Reports Server (NTRS)

Matthews, Janet; Ahmad, Norman; Wilcox, Brian

2007-01-01

A report describes an interface for utilizing some of the mobility features of a mobile robot for general-purpose manipulation of tools and other objects. The robot in question, now undergoing conceptual development for use on the Moon, is the All-Terrain Hex-Limbed Extra-Terrestrial Explorer (ATHLETE) rover, which is designed to roll over gentle terrain or walk over rough or steep terrain. Each leg of the robot is a six-degree-of-freedom general purpose manipulator tipped by a wheel with a motor drive. The tool interface includes a square cross-section peg, equivalent to a conventional socket-wrench drive, that rotates with the wheel. The tool interface also includes a clamp that holds a tool on the peg, and a pair of fold-out cameras that provides close-up stereoscopic images of the tool and its vicinity. The field of view of the imagers is actuated by the clamp mechanism and is specific to each tool. The motor drive can power any of a variety of tools, including rotating tools for helical fasteners, drills, and such clamping tools as pliers. With the addition of a flexible coupling, it could also power another tool or remote manipulator at a short distance. The socket drive can provide very high torque and power because it is driven by the wheel motor.

Positive-Buoyancy Rover for Under Ice Mobility

NASA Technical Reports Server (NTRS)

Leichty, John M.; Klesh, Andrew T.; Berisford, Daniel F.; Matthews, Jaret B.; Hand, Kevin P.

2013-01-01

A buoyant rover has been developed to traverse the underside of ice-covered lakes and seas. The rover operates at the ice/water interface and permits direct observation and measurement of processes affecting freeze- over and thaw events in lake and marine environments. Operating along the 2- D ice-water interface simplifies many aspects of underwater exploration, especially when compared to submersibles, which have difficulty in station-keeping and precision mobility. The buoyant rover consists of an all aluminum body with two aluminum sawtooth wheels. The two independent body segments are sandwiched between four actuators that permit isolation of wheel movement from movement of the central tether spool. For normal operations, the wheels move while the tether spool feeds out line and the cameras on each segment maintain a user-controlled fixed position. Typically one camera targets the ice/water interface and one camera looks down to the lake floor to identify seep sources. Each wheel can be operated independently for precision turning and adjustments. The rover is controlled by a touch- tablet interface and wireless goggles enable real-time viewing of video streamed from the rover cameras. The buoyant rover was successfully deployed and tested during an October 2012 field campaign to investigate methane trapped in ice in lakes along the North Slope of Alaska.

78 FR 695 - 36(b)(1) Arms Sales Notification

Federal Register 2010, 2011, 2012, 2013, 2014

2013-01-04

... Consideration for Purchase: 7 M142 High Mobility Artillery Rocket System (HIMARS) Launchers with the Universal... M68A2 Trainers, 1 Advanced Field Artillery Tactical Data System (AFATDS); 2 M1151A1 High Mobility..., transportation, wheeled vehicles, communications equipment, spare and repair parts, support equipment, tools and...

Mobile Uninterruptible Power Supply

NASA Technical Reports Server (NTRS)

Mears, Robert L.

1990-01-01

Proposed mobile unit provides 20 kVA of uninterruptible power. Used with mobile secondary power-distribution centers to provide power to test equipment with minimal cabling, hazards, and obstacles. Wheeled close to test equipment and system being tested so only short cable connections needed. Quickly moved and set up in new location. Uninterruptible power supply intended for tests which data lost or equipment damaged during even transient power failure.

Mobility Research and Development (Briefing charts)

DTIC Science & Technology

2016-03-17

Mobility Research & Development Dr. Paramsothy Jayakumar, STE, Analytics Tank Automotive Research, Development and Engineering Center Research...Mobility Model (NRMM) • Dr. M. G. Bekker of TARDEC is the “Father of Terrain-Vehicle Systems ” • NRMM was developed in 1960-70 by TARDEC and ERDC...Blocks: Scaled Experiments Particle Image Velocimetry Pressure – Sinkage Test Direct Shear Test Simulations Single Wheel Test Plate width = 50 mm

Simultaneous tracking and regulation visual servoing of wheeled mobile robots with uncalibrated extrinsic parameters

NASA Astrophysics Data System (ADS)

Lu, Qun; Yu, Li; Zhang, Dan; Zhang, Xuebo

2018-01-01

This paper presentsa global adaptive controller that simultaneously solves tracking and regulation for wheeled mobile robots with unknown depth and uncalibrated camera-to-robot extrinsic parameters. The rotational angle and the scaled translation between the current camera frame and the reference camera frame, as well as the ones between the desired camera frame and the reference camera frame can be calculated in real time by using the pose estimation techniques. A transformed system is first obtained, for which an adaptive controller is then designed to accomplish both tracking and regulation tasks, and the controller synthesis is based on Lyapunov's direct method. Finally, the effectiveness of the proposed method is illustrated by a simulation study.

Feasibility of the Enhancing Participation In the Community by improving Wheelchair Skills (EPIC Wheels) program: study protocol for a randomized controlled trial

PubMed Central

2013-01-01

Background Many older adults rely on a manual wheelchair for mobility but typically receive little, if any, training on how to use their wheelchair effectively and independently. Standardized skill training is an effective intervention, but limited access to clinician trainers is a substantive barrier. Enhancing Participation in the Community by Improving Wheelchair Skills (EPIC Wheels) is a 1-month monitored home training program for improving mobility skills in older novice manual wheelchair users, integrating principles from andragogy and social cognitive theory. The purpose of this study is to determine whether feasibility indicators and primary clinical outcome measures of the EPIC Wheels program are sufficiently robust to justify conducting a subsequent multi-site randomized controlled trial. Methods A 2 × 2 factorial randomized controlled trial at two sites will compare improvement in wheelchair mobility skills between an EPIC Wheels treatment group and a computer-game control group, with additional wheelchair use introduced as a second factor. A total of 40 community-dwelling manual wheelchair users at least 55 years old and living in two Canadian metropolitan cities (n = 20 × 2) will be recruited. Feasibility indicators related to study process, resources, management, and treatment issues will be collected during data collection and at the end of the study period, and evaluated against proposed criteria. Clinical outcome measures will be collected at baseline (pre-randomization) and post-intervention. The primary clinical outcome measure is wheelchair skill capacity, as determined by the Wheelchair Skills Test, version 4.1. Secondary clinical outcome measures include wheelchair skill safety, satisfaction with performance, wheelchair confidence, life-space mobility, divided-attention, and health-related quality of life. Discussion The EPIC Wheels training program offers several innovative features. The convenient, portable, economical, and adaptable tablet-based, home program model for wheelchair skills training has great potential for clinical uptake and opportunity for future enhancements. Theory-driven design can foster learning and adherence for older adults. Establishing the feasibility of the study protocol and estimating effect size for the primary clinical outcome measure will be used to develop a multi-site randomized controlled trial to test the guiding hypotheses. Trial registration Clinical Trials NCT01740635. PMID:24156396

Vehicle Performance Recorder (VPR)/ HMMWV (High Mobility Multi-Purpose Wheeled Vehicle) Interface Verification.

DTIC Science & Technology

1984-05-01

hybrid transmission used in the VPR vehicle. From these comparisons made with HMMWV Developmental Test data, confidence can be placed in the validity of...I ............ ........ . ... .... ......... I................ l........ igr 3-2 Drwa pul .1 - hg rne 4004 .. d 3000 \\. PR VEIcLE 2000...Engine: GMC, V-8 diesel, 6.2 L. Transmission: Model THM 475/400 ( hybrid ). Transfer: New process 218, full time 4-wheel drive. Differential: Gleasman

Experimental Investigation of the Robinson-Type Cup Anemometer

NASA Technical Reports Server (NTRS)

Brevoort, M J; Joyner, U T

1936-01-01

This report presents the results of wind tunnel tests on a Robinson-type anemometer. The investigation covered force measurements on individual cups, as well as static and dynamic torque measurements and calibrations on complete cup wheels. In the tests on individual cups 5 cup forms were used and in the measurements on complete cup wheels 4 cup wheels with 3 arm lengths for each cup wheel were tested. All the results are presented in graphical form.

Broken rims in railroad wheels.

DOT National Transportation Integrated Search

2014-12-01

Broken wheels are one of the most common types of equipment-caused train accidents. The failure of rail car wheel rims, which : are usually the result of shattered rims or vertical split rims (VSR), are the leading cause of wheel-related accidents, a...

Cross-Coupled Control for All-Terrain Rovers

PubMed Central

Reina, Giulio

2013-01-01

Mobile robots are increasingly being used in challenging outdoor environments for applications that include construction, mining, agriculture, military and planetary exploration. In order to accomplish the planned task, it is critical that the motion control system ensure accuracy and robustness. The achievement of high performance on rough terrain is tightly connected with the minimization of vehicle-terrain dynamics effects such as slipping and skidding. This paper presents a cross-coupled controller for a 4-wheel-drive/4-wheel-steer robot, which optimizes the wheel motors' control algorithm to reduce synchronization errors that would otherwise result in wheel slip with conventional controllers. Experimental results, obtained with an all-terrain rover operating on agricultural terrain, are presented to validate the system. It is shown that the proposed approach is effective in reducing slippage and vehicle posture errors. PMID:23299625

30 CFR 77.1605 - Loading and haulage equipment; installations.

Code of Federal Regulations, 2010 CFR

2010-07-01

...) Mobile equipment shall be provided with audible warning devices. Lights shall be provided on both ends... windows shall be of safety glass or equivalent, in good condition and shall be kept clean. (b) Mobile... passage of wheels. (h) Rocker-bottom or bottom-dump cars shall be equipped with positive locking devices...

Automated Robot Movement in the Mapped Area Using Fuzzy Logic for Wheel Chair Application

NASA Astrophysics Data System (ADS)

Siregar, B.; Efendi, S.; Ramadhana, H.; Andayani, U.; Fahmi, F.

2018-03-01

The difficulties of the disabled to move make them unable to live independently. People with disabilities need supporting device to move from place to place. For that, we proposed a solution that can help people with disabilities to move from one room to another automatically. This study aims to create a wheelchair prototype in the form of a wheeled robot as a means to learn the automatic mobilization. The fuzzy logic algorithm was used to determine motion direction based on initial position, ultrasonic sensors reading in avoiding obstacles, infrared sensors reading as a black line reader for the wheeled robot to move smooth and smartphone as a mobile controller. As a result, smartphones with the Android operating system can control the robot using Bluetooth. Here Bluetooth technology can be used to control the robot from a maximum distance of 15 meters. The proposed algorithm was able to work stable for automatic motion determination based on initial position, and also able to modernize the wheelchair movement from one room to another automatically.

Wheel-type magnetic refrigerator

DOEpatents

Barclay, John A.

1983-01-01

The disclosure is directed to a wheel-type magnetic refrigerator capable of cooling over a large temperature range. Ferromagnetic or paramagnetic porous materials are layered circumferentially according to their Curie temperature. The innermost layer has the lowest Curie temperature and the outermost layer has the highest Curie temperature. The wheel is rotated through a magnetic field perpendicular to the axis of the wheel and parallel to its direction of rotation. A fluid is pumped through portions of the layers using inner and outer manifolds to achieve refrigeration of a thermal load.

Wheel-type magnetic refrigerator

DOEpatents

Barclay, J.A.

1982-01-20

The disclosure is directed to a wheel-type magnetic refrigerator capable of cooling over a large temperature range. Ferromagnetic or paramagnetic porous materials are layered circumferentially according to their Curie temperature. The innermost layer has the lowest Curie temperature and the outermost layer has the highest Curie temperature. The wheel is rotated through a magnetic field perpendicular to the axis of the wheel and parallel to its direction of rotation. A fluid is pumped through portions of the layers using inner and outer manifolds to achieve refrigeration of a thermal load.

Reinventing the wheel: comparison of two wheel cage styles for assessing mouse voluntary running activity.

PubMed

Seward, T; Harfmann, B D; Esser, K A; Schroder, E A

2018-04-01

Voluntary wheel cage assessment of mouse activity is commonly employed in exercise and behavioral research. Currently, no standardization for wheel cages exists resulting in an inability to compare results among data from different laboratories. The purpose of this study was to determine whether the distance run or average speed data differ depending on the use of two commonly used commercially available wheel cage systems. Two different wheel cages with structurally similar but functionally different wheels (electromechanical switch vs. magnetic switch) were compared side-by-side to measure wheel running data differences. Other variables, including enrichment and cage location, were also tested to assess potential impacts on the running wheel data. We found that cages with the electromechanical switch had greater inherent wheel resistance and consistently led to greater running distance per day and higher average running speed. Mice rapidly, within 1-2 days, adapted their running behavior to the type of experimental switch used, suggesting these running differences are more behavioral than due to intrinsic musculoskeletal, cardiovascular, or metabolic limits. The presence of enrichment or location of the cage had no detectable impact on voluntary wheel running. These results demonstrate that mice run differing amounts depending on the type of cage and switch mechanism used and thus investigators need to report wheel cage type/wheel resistance and use caution when interpreting distance/speed run across studies. NEW & NOTEWORTHY The results of this study highlight that mice will run different distances per day and average speed based on the inherent resistance present in the switch mechanism used to record data. Rapid changes in running behavior for the same mouse in the different cages demonstrate that a strong behavioral factor contributes to classic exercise outcomes in mice. Caution needs to be taken when interpreting mouse voluntary wheel running activity to include potential behavioral input and physiological parameters.

Measurement of Micro Vibration of Car by Piezoelectric Ceramics

NASA Astrophysics Data System (ADS)

Kurihara, Yosuke; Masuyama, Kosuke; Nakamura, Testuo; Bamba, Takeshi; Watanabe, Kajiro

Recently, there are various accidents and crimes related to the car. In some cases, the accidents and the crimes can be prevented if it is possible to detect a human who is in the car. For example, we can prevent a baby who is left in a car under the hot weather from dehydration or death occurred by heat inside disease. In another case, it is estimated that the United States currently has as many as 12 million illegal immigrants. In order to prevent further influx of illegal immigrants, the police are physically searching incoming vehicles at national boundaries aiming at finding those who are hiding inside. However, the physical inspections require much manpower cost and time. An inspection method to see inside the vehicles through X-ray images has also been used for this end. But the cost and the installation places are the problems of the large-scale X-ray system. Proposed in this paper is a piezoelectric ceramic system to handily measure the micro vibrations of motor vehicles. And applying the algorithm of Support Vector Machine (SVM), the existence of human body inside vehicles can be detected. The experiment was carried out using four types of vehicles: a mini car; an auto mobile; a van; and a truck weighing 1.5 tons. As the results, the correct determination ratio was 91.2% for the experiment with the piezoelectric ceramic under the front wheels and 97.0% under the rear wheels, when the vehicle used for the examination had also been used together with other three types of vehicles to obtain SVM training data. When the vehicle used for the examination had not been used together with the other three to obtain SVM training data, on the other hand, the correct determination ratio was 93.7% for the experiment with the piezoelectric ceramic under the front wheels and 95.7% under the rear wheels.

A novel algorithm for detecting active propulsion in wheelchair users following spinal cord injury.

PubMed

Popp, Werner L; Brogioli, Michael; Leuenberger, Kaspar; Albisser, Urs; Frotzler, Angela; Curt, Armin; Gassert, Roger; Starkey, Michelle L

2016-03-01

Physical activity in wheelchair-bound individuals can be assessed by monitoring their mobility as this is one of the most intense upper extremity activities they perform. Current accelerometer-based approaches for describing wheelchair mobility do not distinguish between self- and attendant-propulsion and hence may overestimate total physical activity. The aim of this study was to develop and validate an inertial measurement unit based algorithm to monitor wheel kinematics and the type of wheelchair propulsion (self- or attendant-) within a "real-world" situation. Different sensor set-ups were investigated, ranging from a high precision set-up including four sensor modules with a relatively short measurement duration of 24 h, to a less precise set-up with only one module attached at the wheel exceeding one week of measurement because the gyroscope of the sensor was turned off. The "high-precision" algorithm distinguished self- and attendant-propulsion with accuracy greater than 93% whilst the long-term measurement set-up showed an accuracy of 82%. The estimation accuracy of kinematic parameters was greater than 97% for both set-ups. The possibility of having different sensor set-ups allows the use of the inertial measurement units as high precision tools for researchers as well as unobtrusive and simple tools for manual wheelchair users. Copyright © 2016 IPEM. Published by Elsevier Ltd. All rights reserved.

Use of the Independence 3000 IBOT Transporter at home and in the community.

PubMed

Cooper, Rory A; Boninger, Michael L; Cooper, Rosemarie; Dobson, Annmarie R; Kessler, Jeanette; Schmeler, Mark; Fitzgerald, Shirley G

2003-01-01

The INDEPENDENCE 3000 IBOT Transporter (IBOT) is an electronically stabilizing mobility device for people with disabilities. It operates in 4 functions: Standard, Balance (raised on 2 rear wheels), 4 Wheel (for inclines, curbs, and uneven terrain), and Remote (for loading into a vehicle). The purpose of this study was to observe the IBOT at use in the home and in the community. Data were obtained via observations by trained clinicians, data recorded from a computerized data logger, and reports from each expert. Participants included 10 unimpaired nonwheelchair users (6 men, 4 women) and 4 expert wheelchair users (men with spinal cord injuries, T7-L1). The participants used the IBOT to perform a variety of activities, including holding eye-level discussions with colleagues and shopping by balancing on 2 wheels, going up and down steep ramps, traversing outdoor surfaces (eg, grass, dirt trails), and climbing curbs. The Balance and 4-Wheel functions were helpful and worked well. The IBOT required attention to control in the Standard function. The seat height was too high for most tables and desks, and the IBOT was challenging to use in the bathroom. The IBOT is a functional mobility device that expands the options of wheelchair users. It is most useful outdoors and where there is sufficient space to use its unique Balance function.

Numerical investigation on effect of blade shape for stream water wheel performance.

NASA Astrophysics Data System (ADS)

Yah, N. F.; Oumer, A. N.; Aziz, A. A.; Sahat, I. M.

2018-04-01

Stream water wheels are one of the oldest and commonly used types of wheels for the production of energy. Moreover, they are economical, efficient and sustainable. However, few amounts of research works are available in the open literature. This paper aims to develop numerical model for investigation of the effect of blade shape on the performance of stream water wheel. The numerical model was simulated using Computational Fluid Dynamics (CFD) method and the developed model was validated by comparing the simulation results with experimental data obtained from literature. The performance of straight, curved type 1 and curved type 2 was observed and the power generated by each blade design was identified. The inlet velocity was set to 0.3 m/s static pressure outlet. The obtained results indicate that the highest power was generated by the Curved type 2 compared to straight blade and curved type 1. From the CFD result, Curved type 1 was able to generate 0.073 Watt while Curved type 2 generate 0.064 Watt. The result obtained were consistent with the experiment result hence can be used the numerical model as a guide to numerically predict the water wheel performance

Wheeled and Tracked Vehicle Endurance Testing

DTIC Science & Technology

2014-10-02

Vehicle (ATV) 10 10 50 30 Fire Trucks - Crash and Rescue, Brush, Structural 49/56/50 22/16/50 - 29/28/0 a Wheeled Combat 30 40 15 15 Roboticb - 30 50... Wheeled Light W-M = Wheeled Medium W-H = Wheeled Heavy LM-TT = Light/Medium Truck H-TT = Heavy Truck Tractor/Trailer M = Motorcycle FT = Fire ...TYPE Final 3. DATES COVERED (From - To) 4. TITLE AND SUBTITLE Test Operations Procedure (TOP) 02-2-506A Wheeled and Tracked Vehicle Endurance

A La Carts: You Want Wireless Mobility? Have a COW

ERIC Educational Resources Information Center

Villano, Matt

2006-01-01

Computers on wheels, or COWs, combine the wireless technology of today with the audio/visual carts of yesteryear for an entirely new spin on mobility. Increasingly used by districts with laptop computing initiatives, COWs are among the hottest high-tech sellers in schools today, according to market research firm Quality Education Data. In this…

Design, Implementation and Validation of the Three-Wheel Holonomic Motion System of the Assistant Personal Robot (APR).

PubMed

Moreno, Javier; Clotet, Eduard; Lupiañez, Ruben; Tresanchez, Marcel; Martínez, Dani; Pallejà, Tomàs; Casanovas, Jordi; Palacín, Jordi

2016-10-10

This paper presents the design, implementation and validation of the three-wheel holonomic motion system of a mobile robot designed to operate in homes. The holonomic motion system is described in terms of mechanical design and electronic control. The paper analyzes the kinematics of the motion system and validates the estimation of the trajectory comparing the displacement estimated with the internal odometry of the motors and the displacement estimated with a SLAM procedure based on LIDAR information. Results obtained in different experiments have shown a difference on less than 30 mm between the position estimated with the SLAM and odometry, and a difference in the angular orientation of the mobile robot lower than 5° in absolute displacements up to 1000 mm.

Design, Implementation and Validation of the Three-Wheel Holonomic Motion System of the Assistant Personal Robot (APR)

PubMed Central

Moreno, Javier; Clotet, Eduard; Lupiañez, Ruben; Tresanchez, Marcel; Martínez, Dani; Pallejà, Tomàs; Casanovas, Jordi; Palacín, Jordi

2016-01-01

This paper presents the design, implementation and validation of the three-wheel holonomic motion system of a mobile robot designed to operate in homes. The holonomic motion system is described in terms of mechanical design and electronic control. The paper analyzes the kinematics of the motion system and validates the estimation of the trajectory comparing the displacement estimated with the internal odometry of the motors and the displacement estimated with a SLAM procedure based on LIDAR information. Results obtained in different experiments have shown a difference on less than 30 mm between the position estimated with the SLAM and odometry, and a difference in the angular orientation of the mobile robot lower than 5° in absolute displacements up to 1000 mm. PMID:27735857

Neuro-Analogical Gate Tuning of Trajectory Data Fusion for a Mecanum-Wheeled Special Needs Chair

PubMed Central

ElSaharty, M. A.; zakzouk, Ezz Eldin

2017-01-01

Trajectory tracking of mobile wheeled chairs using internal shaft encoder and inertia measurement unit(IMU), exhibits several complications and accumulated errors in the tracking process due to wheel slippage, offset drift and integration approximations. These errors can be realized when comparing localization results from such sensors with a camera tracking system. In long trajectory tracking, such errors can accumulate and result in significant deviations which make data from these sensors unreliable for tracking. Meanwhile the utilization of an external camera tracking system is not always a feasible solution depending on the implementation environment. This paper presents a novel sensor fusion method that combines the measurements of internal sensors to accurately predict the location of the wheeled chair in an environment. The method introduces a new analogical OR gate structured with tuned parameters using multi-layer feedforward neural network denoted as “Neuro-Analogical Gate” (NAG). The resulting system minimize any deviation error caused by the sensors, thus accurately tracking the wheeled chair location without the requirement of an external camera tracking system. The fusion methodology has been tested with a prototype Mecanum wheel-based chair, and significant improvement over tracking response, error and performance has been observed. PMID:28045973

Wheel-type magnetic refrigerator

DOEpatents

Barclay, J.A.

1983-10-11

The disclosure is directed to a wheel-type magnetic refrigerator capable of cooling over a large temperature range. Ferromagnetic or paramagnetic porous materials are layered circumferentially according to their Curie temperature. The innermost layer has the lowest Curie temperature and the outermost layer has the highest Curie temperature. The wheel is rotated through a magnetic field perpendicular to the axis of the wheel and parallel to its direction of rotation. A fluid is pumped through portions of the layers using inner and outer manifolds to achieve refrigeration of a thermal load. 7 figs.

Two modular neuro-fuzzy system for mobile robot navigation

NASA Astrophysics Data System (ADS)

Bobyr, M. V.; Titov, V. S.; Kulabukhov, S. A.; Syryamkin, V. I.

2018-05-01

The article considers the fuzzy model for navigation of a mobile robot operating in two modes. In the first mode the mobile robot moves along a line. In the second mode, the mobile robot looks for an target in unknown space. Structural and schematic circuit of four-wheels mobile robot are presented in the article. The article describes the movement of a mobile robot based on two modular neuro-fuzzy system. The algorithm of neuro-fuzzy inference used in two modular control system for movement of a mobile robot is given in the article. The experimental model of the mobile robot and the simulation of the neuro-fuzzy algorithm used for its control are presented in the article.

State of the cart.

PubMed

Bernstein, C; Weiss, S; Lorenzini, B

1994-03-15

Food on wheels: it's here, there and everywhere. But while some operations rev up cart expansion plans, others have shifted into low gear. Here's an update on that '90s phenomenon: mobile merchandising.

Advanced Mobility Testbed for Dynamic Semi-Autonomous Unmanned Ground Vehicles

DTIC Science & Technology

2015-04-24

constraint, effectively hiding them from the dynamics solver. Thus the resulting system topology is once again a tree with only inter-body hinges and...the geometry of wheel sinkage (left) and stress distribution under the wheel (right) from reference [24]. With τmax(θ) = c+σ(θ) tan (φ). the shear...sliding). The transversal deflection α or lateral slip angle and the lateral slip coefficient Sα are Sα = tan (α) = −vy vx (12) The comprehensive slip ratio

Development and Testing of a Hybrid Wheg (trademark)-Mobile Platform for Autonomous Surf-Zone Operations

DTIC Science & Technology

2011-12-01

7 Figure 2.1 Force body diagram of a wheel. . . . . . . . . . . . . . . . . . . . . . 9 Figure 2.2 Force body diagram of a person climbing stairs ...person climbing stairs . . . . . 10 Figure 2.4 Plot of the height of center above ground vs. rotation angle for a wheel and Wheg...tail was able to climb an obstacle six centimeters higher than a similar robot with six Whegs [6].The addition of a tail shifted the center of mass

49 CFR 570.59 - Service brake system.

Code of Federal Regulations, 2014 CFR

2014-10-01

... the following tests. (1) Roller-type or drive-on platform tests. The force applied by the brake on a front wheel or a rear wheel shall not differ by more than 25 percent from the force applied by the brake on the other front wheel or the other rear wheel respectively. (i) Inspection procedure. The vehicle...

49 CFR 570.59 - Service brake system.

Code of Federal Regulations, 2010 CFR

2010-10-01

... the following tests. (1) Roller-type or drive-on platform tests. The force applied by the brake on a front wheel or a rear wheel shall not differ by more than 25 percent from the force applied by the brake on the other front wheel or the other rear wheel respectively. (i) Inspection procedure. The vehicle...

49 CFR 570.59 - Service brake system.

Code of Federal Regulations, 2011 CFR

2011-10-01

... the following tests. (1) Roller-type or drive-on platform tests. The force applied by the brake on a front wheel or a rear wheel shall not differ by more than 25 percent from the force applied by the brake on the other front wheel or the other rear wheel respectively. (i) Inspection procedure. The vehicle...

49 CFR 570.59 - Service brake system.

Code of Federal Regulations, 2013 CFR

2013-10-01

... the following tests. (1) Roller-type or drive-on platform tests. The force applied by the brake on a front wheel or a rear wheel shall not differ by more than 25 percent from the force applied by the brake on the other front wheel or the other rear wheel respectively. (i) Inspection procedure. The vehicle...

49 CFR 570.59 - Service brake system.

Code of Federal Regulations, 2012 CFR

2012-10-01

... the following tests. (1) Roller-type or drive-on platform tests. The force applied by the brake on a front wheel or a rear wheel shall not differ by more than 25 percent from the force applied by the brake on the other front wheel or the other rear wheel respectively. (i) Inspection procedure. The vehicle...

A Comparative Study of Soviet versus Western Helicopters. Part 2. Evaluation of Weight, Maintainability, and Design Aspects of Major Components

DTIC Science & Technology

1983-03-01

transmnission ratingob gearbox ult uldiatc gOr tail-rotor gearbox Vr vertical tailh hub w wheelhr horizontal tail w/ wheel -type landing-gear legslob...depends on ýhe type of landing gear (skid, fixed- wheel , or retractable). The RTL approach takes into consideration not only gross weight, but also...depending on the helicopter configuration (single- rotor, tandem, or side-by-side), and the type of landing gear ( wheel or skid). For a single-rotor

Take the Wheel Again...The Right Way: NMEDA's Guide to Choosing the Best Vehicle for You

ERIC Educational Resources Information Center

Exceptional Parent, 2007

2007-01-01

We live in a world where mobility is more necessary than ever before, and adaptive vehicles and other equipment are necessary for some individuals. This article recommends that those in need of an adaptive vehicle or other adaptive equipment always purchase from a National Mobility Equipment Dealers Association (NMEDA) dealer, and discusses the…

Fully decentralized estimation and control for a modular wheeled mobile robot

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

Mutambara, A.G.O.; Durrant-Whyte, H.F.

2000-06-01

In this paper, the problem of fully decentralized data fusion and control for a modular wheeled mobile robot (WMR) is addressed. This is a vehicle system with nonlinear kinematics, distributed multiple sensors, and nonlinear sensor models. The problem is solved by applying fully decentralized estimation and control algorithms based on the extended information filter. This is achieved by deriving a modular, decentralized kinematic model by using plane motion kinematics to obtain the forward and inverse kinematics for a generalized simple wheeled vehicle. This model is then used in the decentralized estimation and control algorithms. WMR estimation and control is thusmore » obtained locally using reduced order models with reduced communication of information between nodes is carried out after every measurement (full rate communication), the estimates and control signals obtained at each node are equivalent to those obtained by a corresponding centralized system. Transputer architecture is used as the basis for hardware and software design as it supports the extensive communication and concurrency requirements that characterize modular and decentralized systems. The advantages of a modular WMR vehicle include scalability, application flexibility, low prototyping costs, and high reliability.« less

Mechanical Design Engineering Enabler Project wheel and wheel drives

NASA Technical Reports Server (NTRS)

Nutt, Richard E.; Couch, Britt K.; Holley, John L., Jr.; Garris, Eric S.; Staut, Paul V.

1992-01-01

Our group was assigned the responsibility of designing the wheel and wheel drive system for a proof-of-concept model of the lunar-based ENABLER. ENABLER is a multi-purpose, six wheeled vehicle designed to lift and transport heavy objects associated with the construction of a lunar base. The resulting design was based on the performance criteria of the ENABLER. The drive system was designed to enable the vehicle to achieve a speed of 7 mph on a level surface, climb a 30 percent grade, and surpass a one meter high object and one meter wide crevice. The wheel assemblies were designed to support the entire weight of the vehicle on two wheels. The wheels were designed to serve as the main component of the vehicle's suspension and will provide suitable traction for lunar-type surfaces. The expected performance of the drive system for the ENABLER was influenced by many mechanical factors. The expected top speed on a level sandy surface is 4 mph instead of the desired 7 mph. This is due to a lack of necessary power at the wheels. The lack of power resulted from dimension considerations that allowed only an eight horsepower engine and also from mechanical inefficiencies of the hydraulic system. However, the vehicle will be able to climb a 30 percent grade, surpass a one meter high object and one meter wide crevice. The wheel assemblies will be able to support the entire weight of the vehicle on two wheels. The wheels will also provide adequate suspension for the vehicle and sufficient traction for lunar-type surfaces.

Comparison of different vehicle power trains

NASA Astrophysics Data System (ADS)

Mizsey, Peter; Newson, Esmond

Four different alternatives of mobile power train developments (hybrid diesel, fuel cell operating with hydrogen produced on a petrochemical basis, methanol reformer-fuel cell system, gasoline reformer-fuel cell system), are compared with the gasoline internal combustion engine (ICE), for well-to-wheel efficiencies, CO 2 emissions, and investment costs. Although the ICE requires the lowest investment cost, it is not competitive in well-to-wheel efficiencies and less favourable than the above alternatives for CO 2 emissions. The hybrid diesel power train has the highest well-to-wheel efficiency (30%), but its well-to-wheel carbon dioxide emission is similar to that of the fuel cell power train operated with compressed hydrogen produced on a centralised petrochemical basis. This latter case, however, has the advantage over the hybrid diesel power train that the carbon dioxide emission is concentrated and easier to control than the several point-like sources of emissions. Among the five cases studied only the on-board reforming of methanol offers the possibility of using a renewable energy source (biomass).

Dynamics of a Two-Link Vehicle in an L-Shaped Corridor Revisited

NASA Astrophysics Data System (ADS)

Antonyuk, E. Ya.; Zabuga, A. T.

2014-03-01

The kinematics of a two-link mobile robot with three steerable wheels moving in an L-shaped corridor is analyzed. A smooth (with continuous first derivative) path is designed maintaining the optimal maneuverability of the vehicle. The motion of the vehicle along this path is planned. Analytical expressions for the reactions at the contact of the wheels with the ground are given in the general case of motion. The radius of curvature of the programmed path is shown to have a strong influence on the reactions.

Novel Straight Road Driving Control of Power Assisted Wheelchair Based on Disturbance Estimation of Right and Left Wheels

NASA Astrophysics Data System (ADS)

Seki, Hirokazu; Sugimoto, Takeaki; Tadakuma, Susumu

This paper describes a novel straight road driving control scheme of power assisted wheelchair. Power assisted wheelchair which assists the driving force by electric motors is expected to be widely used as a mobility support system for elderly people and disabled people. The straight driving can be prevented by the road conditions such as branches, grass and carpets because the right and left wheels drive independently. This paper proposes a straight road driving control system based on the disturbance torque estimation. The proposed system estimates the difference of the driving torque by disturbance torque observer and compensates to one side of the wheels. Some practical driving experiments on various road conditions show the effectiveness of the proposed control system.

Characterization of Fillite as a planetary soil simulant in support of rover mobility assessment in high-sinkage/high-slip environments

NASA Astrophysics Data System (ADS)

Edwards, Michael

This thesis presents the results of a research program characterizing a soil simulant called Fillite, which is composed of alumino-silicate hollow microspheres harvested from the pulverized fuel ash of coal-fired power plants. Fillite is available in large quantities at a reasonable cost and it is chemically inert. Fillite has been selected by the National Aeronautics and Space Administration (NASA) Glenn Research Center to simulate high-sinkage/high-slip environment in a large test bed such as the ones encountered by the Spirit rover on Mars in 2009 when it became entrapped in a pocket of soft, loose regolith on Mars. The terms high-sinkage and high-slip used here describe the interaction of soils with typical rover wheels. High-sinkage refers to a wheel sinking with little to no applied force while high-slip refers to a spinning wheel with minimal traction. Standard material properties (density, specific gravity, compression index, Young's modulus, and Poisson's ratio) of Fillite were determined from a series of laboratory tests conducted in general accordance with ASTM standards. Tests were also performed to determine some less standard material properties of Fillite such as the small strain shear wave velocity, maximum shear modulus, and several pressure-sinkage parameters for use in pressure-sinkage models. The experiments include an extensive series of triaxial compression tests, bender element tests, and normal and shear bevameter tests. The unit weight of Fillite on Earth ranges between 3.9 and 4.8 kN/m 3, which is similar to that of Martian regolith (about 3.7 -- 5.6 kN/m3) on Mars and close to the range of the unit weight of lunar regolith (about 1.4 -- 2.9 kN/m3) on the Moon. The data presented here support that Fillite has many physical and mechanical properties that are similar to what is known about Martian regolith. These properties are also comparable to lunar regolith. Fillite is quite dilatant; its peak and critical angles of internal friction are smaller than those of most other simulants. Smaller shear strength, coupled with much smaller bulk unit weight as compared to other simulants, results in smaller bearing and shearing resistances allowing for better simulation of the intended high-sinkage, high-slip behavior for rover mobility studies. The results of the normal bevameter tests were used to determine parameters for two models available in the literature - the Bekker model and the New Model of Mobility (N2M) model. These parameters were then used to predict the sinkage of a Spirit rover wheel if the rover were to be used on Fillite. The predicted sinkage of a Spirit rover wheel in Fillite was 84% of the wheel diameter, which was within the observed sinkage of 50 to 90% of the wheel diameter of the Spirit rover on Mars. Shear bevameter tests were also performed on Fillite to assess the shear stresses and shear deformations imparted by wheels under torsional loads. The results compared well to the estimated shear stresses and deformations of Martian soil caused by the wheels of the Spirit rover. When compared to other simulants (e.g. GRC-1), the pressure-sinkage and shear stress-shear deformation behaviors of Fillite confirm that Fillite is more suitable for high-sinkage and high-slip rover studies than other typical simulants derived from natural terrestrial soils and rocks.

a Traffic-Dependent Acoustical Grinding Criterion

NASA Astrophysics Data System (ADS)

DINGS, P.; VERHEIJEN, E.; KOOTWIJK-DAMMAN, C.

2000-03-01

On most lines of the Dutch railway network, where a substantial amount of block-braked trains have rough wheels, the average wheel roughness dominates over the rail roughness. Therefore, reducing wheel roughness is top priority in the Netherlands. However, for the situations where rail roughness exceeds wheel roughness, this roughness can be lowered at acceptable cost. The high rail roughness is often due to rail corrugation which can be removed by grinding. A method has been developed to assess periodically the rail roughness on each railway line of the network, to compare it with the average wheel roughness for that line and to determine whether a noise reduction can be achieved by grinding the rail. Roughness measurements can be carried out with an instrumented coach. The two axle-boxes of a measurement wheelset are equipped with accelerometers. Together with the train speed and the right frequency filter, the accelerometer signal is used to produce a wavelength spectrum of the rail roughness. To determine the average wheel roughness on a given line, the so-called Acoustical Timetable can be used. This database comprises train types, train intensities and train speeds for each track section in the Netherlands. An average wheel roughness spectrum is known for each type of braking system. The number of trains of each type passing by on a certain track section determine the average roughness. Analysis of the data shows on which track sections the rail roughness exceeds the wheel roughness by a specified level difference. If this track section lies in a residential area, the decision can be made to grind this piece of track to reduce the noise production locally. Using this methodology, the noise production can be kept to a minimum, determined by the local average wheel roughness.

Engineering report. Part 1: NASA wheel air seal development for space shuttle type environmental requirements

NASA Technical Reports Server (NTRS)

1973-01-01

The sealing techniques are studied for existing aircraft wheel-tire designs to meet the hard vacuum .00001 torr and cold temperature -65 F requirements of space travel. The investigation covers the use of existing wheel seal designs.

Determination of vertical pressures on running wheels of freight trolleys of bridge type cranes

NASA Astrophysics Data System (ADS)

Goncharov, K. A.; Denisov, I. A.

2018-03-01

The problematic issues of the design of the bridge-type trolley crane, connected with ensuring uniform load distribution between the running wheels, are considered. The shortcomings of the existing methods of calculation of reference pressures are described. The results of the analytical calculation of the pressure of the support wheels are compared with the results of the numerical solution of this problem for various schemes of trolley supporting frames. Conclusions are given on the applicability of various methods for calculating vertical pressures, depending on the type of metal structures used in the trolley.

Dynamics and control for Constrained Multibody Systems modeled with Maggi's equation: Application to Differential Mobile Robots Partll

NASA Astrophysics Data System (ADS)

Amengonu, Yawo H.; Kakad, Yogendra P.

2014-07-01

Quasivelocity techniques were applied to derive the dynamics of a Differential Wheeled Mobile Robot (DWMR) in the companion paper. The present paper formulates a control system design for trajectory tracking of this class of robots. The method develops a feedback linearization technique for the nonlinear system using dynamic extension algorithm. The effectiveness of the nonlinear controller is illustrated with simulation example.

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

Mobility and Transportability Assessment of a Generic High Mobility Multipurpose Wheeled Vehicle (HMMWV).

DTIC Science & Technology

1983-02-01

NO-GO 16.8 HMMWVG 16.3 NO-GO 18.6 13.n NO-GO 16.8 HMMWV W/SHELTER 16.1 NO-GO 18.3 13.0 NO-GO 16.8 6 II TABLE I PREDICTED VEHICLE MORILITY CUMULATIVE...TACTICAL MORILITY LEVELS WEST GERMANY-DRY MID-EAST )RY TACTICAL TACTICAL TACTICAL TACTICAL TACTICAL TAC TIC.’L VEHICLE HIGH STANDARD SUPPORT HIGH

Engineering report. Part 2: NASA wheel and brake material tradeoff study for space shuttle type environmental requirements

NASA Technical Reports Server (NTRS)

Bok, L. D.

1973-01-01

The study included material selection and trade-off for the structural components of the wheel and brake optimizing weight vs cost and feasibility for the space shuttle type application. Analytical methods were used to determine section thickness for various materials, and a table was constructed showing weight vs. cost trade-off. The wheel and brake were further optimized by considering design philosophies that deviate from standard aircraft specifications, and designs that best utilize the materials being considered.

Distributed Finite-Time Cooperative Control of Multiple High-Order Nonholonomic Mobile Robots.

PubMed

Du, Haibo; Wen, Guanghui; Cheng, Yingying; He, Yigang; Jia, Ruting

2017-12-01

The consensus problem of multiple nonholonomic mobile robots in the form of high-order chained structure is considered in this paper. Based on the model features and the finite-time control technique, a finite-time cooperative controller is explicitly constructed which guarantees that the states consensus is achieved in a finite time. As an application of the proposed results, finite-time formation control of multiple wheeled mobile robots is studied and a finite-time formation control algorithm is proposed. To show effectiveness of the proposed approach, a simulation example is given.

Performance of the Boeing LRV wheels in a lunar soil simulant. Report 2: Effects of speed, Wheel load, and soil

NASA Technical Reports Server (NTRS)

Melzer, K.

1971-01-01

Two nearly identical Boeing-GM wire-mesh Lunar Roving Vehicle (LRV) wheels were laboratory tested in a lunar soil simulant to determine the influence of wheel speed and acceleration, wheel load, presence of a fender, travel direction, and soil strength on the wheel performance. Constant-slip and three types of programmed-slip tests were conducted with a single-wheel dynamometer system. Test results indicated that performance of single LRV wheels in terms of pull coefficient, power number, and efficiency were not influenced by wheel speed and acceleration, travel direction, the presence of a fender, or wheel load. Of these variables, only load influenced sinkage, which increased with increasing load. For a given slip, the pull coefficient and power number increased with increasing soil strength. However, for a given pull coefficient or slope, slip was less in firmer soil; thus, the power number decreased and efficiency increased with increasing soil strength.

Non-Circular Wheels: Reuleaux and Squares

ERIC Educational Resources Information Center

Mills, Allan

2011-01-01

Circular wheels are so familiar on vehicles of all types that it is seldom realized that alternatives do exist. This short non-mathematical article describes Reuleaux and square wheels that, rolling along appropriate tracks, can maintain a moving platform at a constant height. Easily made working models lend themselves to demonstrations at science…

Magnetic suspension options for spacecraft inertia-wheel applications

NASA Technical Reports Server (NTRS)

Downer, J. R.

1984-01-01

Design criteria for spacecraft inertia-wheel suspensions are listed. The advantages of magnetic suspensions over other suspension types for spacecraft inertia-wheel applications are cited along with the functions performed by magnetic suspension. The common designs for magnetic suspensions are enumerated. Materials selection of permanent magnets and core materials is considered.

Voluntary exercise during extinction of auditory fear conditioning reduces the relapse of fear associated with potentiated activity of striatal direct pathway neurons

PubMed Central

Mika, Agnieszka; Bouchet, Courtney A.; Bunker, Preston; Hellwinkel, Justin E.; Spence, Katie G.; Day, Heidi E.W.; Campeau, Serge; Fleshner, Monika

2015-01-01

Relapse of previously extinguished fear presents a significant, pervasive obstacle to the successful long-term treatment of anxiety and trauma-related disorders. Thus, identification of a novel means to enhance fear extinction to stand the passage of time and generalize across contexts is of the utmost importance. Acute bouts of exercise can be used as inexpensive, noninvasive treatment strategies to reduce anxiety, and have been shown to enhance memory for extinction when performed in close temporal proximity to the extinction session. However, it is unclear whether acute exercise can be used to prevent relapse of fear, and the neural mechanisms underlying this potential effect are unknown. The current study therefore examined whether acute exercise during extinction of auditory fear can protect against the later relapse of fear. Male, F344 rats lacking an extended history of wheel running were conditioned to fear a tone CS and subsequently extinguished within either a freely mobile running wheel, a locked wheel, or a control context lacking a wheel. Rats exposed to fear extinction within a freely mobile wheel ran during fear extinction, and demonstrated reduced fear as well as attenuated corticosterone levels during re-exposure to the extinguished CS during the relapse test in a novel context 1 week later. Examination of cfos mRNA patterns elicited by re-exposure to the extinguished CS during the relapse test revealed that acute exercise during extinction decreased activation of brain circuits classically involved in driving fear expression and interestingly, increased activity within neurons of the direct striatal pathway involved in reward signaling. These data suggest that exercise during extinction reduces relapse through a mechanism involving the direct pathway of the striatum. It is suggested that a positive affective state could become associated with the CS during exercise during extinction, thus resulting in a relapse-resistant extinction memory. PMID:26454156

Voluntary exercise during extinction of auditory fear conditioning reduces the relapse of fear associated with potentiated activity of striatal direct pathway neurons.

PubMed

Mika, Agnieszka; Bouchet, Courtney A; Bunker, Preston; Hellwinkel, Justin E; Spence, Katie G; Day, Heidi E W; Campeau, Serge; Fleshner, Monika; Greenwood, Benjamin N

2015-11-01

Relapse of previously extinguished fear presents a significant, pervasive obstacle to the successful long-term treatment of anxiety and trauma-related disorders. Thus, identification of a novel means to enhance fear extinction to stand the passage of time and generalize across contexts is of the utmost importance. Acute bouts of exercise can be used as inexpensive, noninvasive treatment strategies to reduce anxiety, and have been shown to enhance memory for extinction when performed in close temporal proximity to the extinction session. However, it is unclear whether acute exercise can be used to prevent relapse of fear, and the neural mechanisms underlying this potential effect are unknown. The current study therefore examined whether acute exercise during extinction of auditory fear can protect against the later relapse of fear. Male F344 rats lacking an extended history of wheel running were conditioned to fear a tone CS and subsequently extinguished within either a freely mobile running wheel, a locked wheel, or a control context lacking a wheel. Rats exposed to fear extinction within a freely mobile wheel ran during fear extinction, and demonstrated reduced fear as well as attenuated corticosterone levels during re-exposure to the extinguished CS during the relapse test in a novel context 1week later. Examination of cfos mRNA patterns elicited by re-exposure to the extinguished CS during the relapse test revealed that acute exercise during extinction decreased activation of brain circuits classically involved in driving fear expression and interestingly, increased activity within neurons of the direct striatal pathway involved in reward signaling. These data suggest that exercise during extinction reduces relapse through a mechanism involving the direct pathway of the striatum. It is suggested that a positive affective state could become associated with the CS during exercise during extinction, thus resulting in a relapse-resistant extinction memory. Copyright © 2015 Elsevier Inc. All rights reserved.

Inflammation-induced decrease in voluntary wheel running in mice: a nonreflexive test for evaluating inflammatory pain and analgesia.

PubMed

Cobos, Enrique J; Ghasemlou, Nader; Araldi, Dionéia; Segal, David; Duong, Kelly; Woolf, Clifford J

2012-04-01

Inflammatory pain impacts adversely on the quality of life of patients, often resulting in motor disabilities. Therefore, we studied the effect of peripheral inflammation induced by intraplantar administration of complete Freund's adjuvant (CFA) in mice on a particular form of voluntary locomotion, wheel running, as an index of mobility impairment produced by pain. The distance traveled over 1 hour of free access to activity wheels decreased significantly in response to hind paw inflammation, peaking 24 hours after CFA administration. Recovery of voluntary wheel running by day 3 correlated with the ability to support weight on the inflamed limb. Inflammation-induced mechanical hypersensitivity, measured with von Frey hairs, lasted considerably longer than the impaired voluntary wheel running and is not driving; therefore, the change in voluntary behavior. The CFA-induced decrease in voluntary wheel running was dose-dependently reversed by subcutaneous administration of antiinflammatory and analgesic drugs, including naproxen (10-80 mg/kg), ibuprofen (2.5-20mg/kg), diclofenac (1.25-10mg/kg), celecoxib (2.5-20mg/kg), prednisolone (0.62-5mg/kg), and morphine (0.06-0.5mg/kg), all at much lower doses than reported in most rodent models. Furthermore, the doses that induced recovery in voluntary wheel running did not reduce CFA-induced mechanical allodynia, indicating a greater sensitivity of the former as a surrogate measure of inflammatory pain. We conclude that monitoring changes in voluntary wheel running in mice during peripheral inflammation is a simple, observer-independent objective measure of functional changes produced by inflammation, likely more aligned to the global level of pain than reflexive measures, and much more sensitive to analgesic drug effects. Copyright © 2012 International Association for the Study of Pain. Published by Elsevier B.V. All rights reserved.

Coordinated Control Of Mobile Robotic Manipulators

NASA Technical Reports Server (NTRS)

Seraji, Homayoun

1995-01-01

Computationally efficient scheme developed for on-line coordinated control of both manipulation and mobility of robots that include manipulator arms mounted on mobile bases. Applicable to variety of mobile robotic manipulators, including robots that move along tracks (typically, painting and welding robots), robots mounted on gantries and capable of moving in all three dimensions, wheeled robots, and compound robots (consisting of robots mounted on other robots). Theoretical basis discussed in several prior articles in NASA Tech Briefs, including "Increasing the Dexterity of Redundant Robots" (NPO-17801), "Redundant Robot Can Avoid Obstacles" (NPO-17852), "Configuration-Control Scheme Copes With Singularities" (NPO-18556), "More Uses for Configuration Control of Robots" (NPO-18607/NPO-18608).

Design and manufacture of wheels for a dual-mode (manned - automatic) lunar surface roving vehicle. Volume 1: Detailed technical report

NASA Technical Reports Server (NTRS)

1970-01-01

The concept development, testing, evaluation, and the selection of a final wheel design concept for a dual-mode lunar surface vehicle (DLRV) is detailed. Four wheel configurations were fabricated (one open wheel and three closed wheel) (and subjected to a series of soft soil, mechanical, and endurance tests. Results show that the open wheel has lower draw-bar pull (slope climbing) capability in loose soil due to its higher ground pressure and tendency to dig in at high wheel slip. Endurance tests indicate that a double mesh, fully enclosed wheel can be developed to meet DLRV life requirements. There is, however, a 1.0 to 1.8 lb/wheel weight penalty associated with the wheel enclosure. Also the button cleats used as grousers for the closed-type wheels result in local stress concentration and early fatigue failure of the wire mesh. Load deflection tests indicate that the stiffness of the covered wheel increased by up to 50% after soil bin testing, due to increased friction between the fabric and the wire mesh caused by the sand. No change in stiffness was found for the open wheel. The single woven mesh open wheel design with a chevron tread is recommended for continued development

Amorphous Rover

NASA Technical Reports Server (NTRS)

Curtis, Steven A.

2010-01-01

A proposed mobile robot, denoted the amorphous rover, would vary its own size and shape in order to traverse terrain by means of rolling and/or slithering action. The amorphous rover was conceived as a robust, lightweight alternative to the wheeled rover-class robotic vehicle heretofore used in exploration of Mars. Unlike a wheeled rover, the amorphous rover would not have a predefined front, back, top, bottom, or sides. Hence, maneuvering of the amorphous rover would be more robust: the amorphous rover would not be vulnerable to overturning, could move backward or sideways as well as forward, and could even narrow itself to squeeze through small openings.

Automatic Mechetronic Wheel Light Device

DOEpatents

Khan, Mohammed John Fitzgerald

2004-09-14

A wheel lighting device for illuminating a wheel of a vehicle to increase safety and enhance aesthetics. The device produces the appearance of a "ring of light" on a vehicle's wheels as the vehicle moves. The "ring of light" can automatically change in color and/or brightness according to a vehicle's speed, acceleration, jerk, selection of transmission gears, and/or engine speed. The device provides auxiliary indicator lights by producing light in conjunction with a vehicle's turn signals, hazard lights, alarm systems, and etc. The device comprises a combination of mechanical and electronic components and can be placed on the outer or inner surface of a wheel or made integral to a wheel or wheel cover. The device can be configured for all vehicle types, and is electrically powered by a vehicle's electrical system and/or battery.

Motion Simulation Research Related Short Term Training Attachment to TARDEC

DTIC Science & Technology

2013-04-01

CASSI group has five main areas of focus, which are, ground vehicle power and mobility , vehicle electronics and architecture, intelligent ground...control, steering as well as seats can all be changed to mock the necessary vehicle. Originally it was designed for a High Mobility Multipurpose Wheeled...necessary outputs to the motion base. SimCreator is a software package, similar to SimuLink. Most of the backend coding is done in C++. RTI accounts

14 CFR 23.725 - Limit drop tests.

Code of Federal Regulations, 2010 CFR

2010-01-01

... the airplane in the level attitude (with the nose wheel clear in the case of nose wheel type airplanes... the tail-down attitude; W=W N for nose wheel units lbs.), equal to the vertical component of the... attitude, and applied drag loads, that represent the landing conditions. (d) The value of d used in the...

Friction drive position transducer

NASA Astrophysics Data System (ADS)

Waclawik, Ronald E.; Cayer, James L.; Lapointe, Kenneth M.

1991-10-01

A spring force loaded contact wheel mounted in a stationary position relative to a reciprocating shaft is disclosed. The apparatus of the present invention includes a tensioning assembly for maintaining absolute contact between the contact wheel and the reciprocating shaft wherein the tensioning assembly urges the contact wheel against the shaft to maintain contact therebetween so that the wheel turns as the shaft is linearly displaced. A rotary encoding device is coupled to the wheel for translating the angular and rotational movement thereof into an electronic signal for providing linear displacement information and derivative data with respect to displacement of the shaft. Absolute friction contact and cooperative interaction between the shaft and the contact wheel is further enhanced in the preferred embodiment by advantageously selecting the types of surface finish and the amount of surface area of the contact wheel relative to the surface condition of the shaft as well as by reducing the moment of inertia of the contact wheel.

Friction drive position transducer

NASA Astrophysics Data System (ADS)

Waclawik, Ronald E.; Cayer, James L.; Lapointe, Kenneth M.

1993-06-01

A spring force loaded contact wheel mounted in a stationary position relative to a reciprocating shaft is disclosed. The apparatus of the present invention includes a tensioning assembly for maintaining absolute contact between the contact wheel and the reciprocating shaft wherein the tensioning assembly urges the contact wheel against the shaft to maintain contact there between so that the wheel turn as the shaft is linearly displaced. A rotary encoding device is coupled to the wheel for translating the angular and rotational movement thereof into an electronic signal for providing linear displacement information and derivative data with respect to displacement of the shaft. Absolute friction contact and cooperative interaction between the shaft and the contact wheel is further enhanced in the preferred embodiment by advantageously selecting the type of surface finish and the amount of surface area of the contact wheel relative to the surface condition of the shaft as well as by reducing the moment of inertia of the contact wheel.

Sensor Fusion Based Model for Collision Free Mobile Robot Navigation

PubMed Central

Almasri, Marwah; Elleithy, Khaled; Alajlan, Abrar

2015-01-01

Autonomous mobile robots have become a very popular and interesting topic in the last decade. Each of them are equipped with various types of sensors such as GPS, camera, infrared and ultrasonic sensors. These sensors are used to observe the surrounding environment. However, these sensors sometimes fail and have inaccurate readings. Therefore, the integration of sensor fusion will help to solve this dilemma and enhance the overall performance. This paper presents a collision free mobile robot navigation based on the fuzzy logic fusion model. Eight distance sensors and a range finder camera are used for the collision avoidance approach where three ground sensors are used for the line or path following approach. The fuzzy system is composed of nine inputs which are the eight distance sensors and the camera, two outputs which are the left and right velocities of the mobile robot’s wheels, and 24 fuzzy rules for the robot’s movement. Webots Pro simulator is used for modeling the environment and the robot. The proposed methodology, which includes the collision avoidance based on fuzzy logic fusion model and line following robot, has been implemented and tested through simulation and real time experiments. Various scenarios have been presented with static and dynamic obstacles using one robot and two robots while avoiding obstacles in different shapes and sizes. PMID:26712766

Sensor Fusion Based Model for Collision Free Mobile Robot Navigation.

PubMed

Almasri, Marwah; Elleithy, Khaled; Alajlan, Abrar

2015-12-26

Autonomous mobile robots have become a very popular and interesting topic in the last decade. Each of them are equipped with various types of sensors such as GPS, camera, infrared and ultrasonic sensors. These sensors are used to observe the surrounding environment. However, these sensors sometimes fail and have inaccurate readings. Therefore, the integration of sensor fusion will help to solve this dilemma and enhance the overall performance. This paper presents a collision free mobile robot navigation based on the fuzzy logic fusion model. Eight distance sensors and a range finder camera are used for the collision avoidance approach where three ground sensors are used for the line or path following approach. The fuzzy system is composed of nine inputs which are the eight distance sensors and the camera, two outputs which are the left and right velocities of the mobile robot's wheels, and 24 fuzzy rules for the robot's movement. Webots Pro simulator is used for modeling the environment and the robot. The proposed methodology, which includes the collision avoidance based on fuzzy logic fusion model and line following robot, has been implemented and tested through simulation and real time experiments. Various scenarios have been presented with static and dynamic obstacles using one robot and two robots while avoiding obstacles in different shapes and sizes.

Low-cost real-time automatic wheel classification system

NASA Astrophysics Data System (ADS)

Shabestari, Behrouz N.; Miller, John W. V.; Wedding, Victoria

1992-11-01

This paper describes the design and implementation of a low-cost machine vision system for identifying various types of automotive wheels which are manufactured in several styles and sizes. In this application, a variety of wheels travel on a conveyor in random order through a number of processing steps. One of these processes requires the identification of the wheel type which was performed manually by an operator. A vision system was designed to provide the required identification. The system consisted of an annular illumination source, a CCD TV camera, frame grabber, and 386-compatible computer. Statistical pattern recognition techniques were used to provide robust classification as well as a simple means for adding new wheel designs to the system. Maintenance of the system can be performed by plant personnel with minimal training. The basic steps for identification include image acquisition, segmentation of the regions of interest, extraction of selected features, and classification. The vision system has been installed in a plant and has proven to be extremely effective. The system properly identifies the wheels correctly up to 30 wheels per minute regardless of rotational orientation in the camera's field of view. Correct classification can even be achieved if a portion of the wheel is blocked off from the camera. Significant cost savings have been achieved by a reduction in scrap associated with incorrect manual classification as well as a reduction of labor in a tedious task.

29 CFR 1910.241 - Definitions.

Code of Federal Regulations, 2014 CFR

2014-07-01

... dimension. They are subject to the same limitations of use and mounting as Type 1 wheels defined in... dimensions D and J, and in addition have thickness, hole size, rim and back thickness dimensions. Grinding is always performed on rim face, W dimension. Type 11 wheels are subject to all limitations of use and...

29 CFR 1910.241 - Definitions.

Code of Federal Regulations, 2012 CFR

2012-07-01

... dimension. They are subject to the same limitations of use and mounting as Type 1 wheels defined in... dimensions D and J, and in addition have thickness, hole size, rim and back thickness dimensions. Grinding is always performed on rim face, W dimension. Type 11 wheels are subject to all limitations of use and...

29 CFR 1910.241 - Definitions.

Code of Federal Regulations, 2013 CFR

2013-07-01

... dimension. They are subject to the same limitations of use and mounting as Type 1 wheels defined in... dimensions D and J, and in addition have thickness, hole size, rim and back thickness dimensions. Grinding is always performed on rim face, W dimension. Type 11 wheels are subject to all limitations of use and...

Development and pilot testing of a kneeling ultralight wheelchair design.

PubMed

Mattie, Johanne L; Leland, Danny; Borisoff, Jaimie F

2015-01-01

"Dynamic wheeled mobility" offers "on the fly" seating adjustments for wheelchair users such that various activities performed throughout the day can be matched by an appropriate seat position. While this has benefits for user participation and health, the added weight in existing dynamic wheelchairs may impact the user's ability to transport the frame, e.g. into cars. Other dynamic features to enable more participation avenues are also desirable. This paper outlines the development of a "kneeling" ultralight wheelchair design that offers dynamic wheeled mobility functionality at a weight that is comparable to many existing ultralight wheelchairs. In addition, the wheelchair's kneeling function allows a lowered seat position to facilitate low-to-the-ground tasks such as floor transfers and other activities where sustained low level reaching may be required (e.g. playing with children, changing a tire, etc.). This paper also describes the development and pilot testing of an end user evaluation protocol designed to validate the wheelchair's functionality and performance. Successful realization and commercialization of the technology would offer a novel product choice for people with mobility disabilities, and that may support daily activities, health, improved quality of life, and greater participation in the community.

Development and validation of a new kind of coupling element for wheel-hub motors

NASA Astrophysics Data System (ADS)

Perekopskiy, Sergey; Kasper, Roland

2018-05-01

For the automotive industry, electric powered vehicles are becoming an increasingly relevant factor in the competition against climate change. Application of one special example - a wheel-hub motor, for electric powered vehicle can support this challenge. Patented slotless air gap winding invented at the chair of mechatronics of the Otto von Guericke University Magdeburg has great application potential in constantly growing e-mobility field, especially for wheel-hub motors based on this technology due to its advantages, such as a high gravimetric power density and high efficiency. However, advantages of this technology are decreased by its sensibility to the loads out of driving maneuvers by dimensional variations of air gap consistency. This article describes the development and validation of a coupling element for the designed wheel-hub motor. To find a suitable coupling concept first the assembly structure of the motor was analyzed and developed design of the coupling element was checked. Based on the geometry of the motor and wheel a detailed design of the coupling element was generated. The analytical approach for coupling element describes a potential of the possible loads on the coupling element. The FEM simulation of critical load cases for the coupling element validated results of the analytical approach.

A Network on Wheels!

ERIC Educational Resources Information Center

Harper, Christopher

1994-01-01

Describes mobile computer carts developed at the Lawrence Hall of Science that use IBM PS/2 computers and Personal Science Laboratory probeware. Activities using temperature probes for elementary and secondary school students are described, including greenhouse environments, ice cream/chemical reactions, probe races, motion studies, and…

Riding the Ferris Wheel: A Sinusoidal Model

ERIC Educational Resources Information Center

Mittag, Kathleen Cage; Taylor, Sharon E.

2011-01-01

When thinking of models for sinusoidal waves, examples such as tides of the ocean, daily temperatures for one year in your town, light and sound waves, and certain types of motion are used. Many textbooks [1, p. 222] also present a "Ferris wheel description problem" for students to work. This activity takes the Ferris wheel problem out of the…

Novel Straight and Circular Road Driving Control of Electric Power Assisted Wheelchair Based on Fuzzy Algorithm

NASA Astrophysics Data System (ADS)

Seki, Hirokazu; Tadakuma, Susumu

This paper describes a novel straight and circular road driving control scheme for electric power assisted wheelchairs. “Electric power assisted wheelchair” which assists 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 performance of the straight and circular road driving must be further improved because the two wheels drive independently. This paper proposes a novel driving control scheme based on fuzzy algorithm to realize the stable and reliable driving on straight and circular roads. The suitable assisted torque of the right and left wheels is determined by fuzzy algorithm based on the posture angular velocity of the wheelchair and the human input torque proportion of the right and left wheels. Some experiments on the practical roads show the effectiveness of the proposed control system.

Operationality Improvement Control of Electric Power Assisted Wheelchair by Fuzzy Algorithm Considering Posture Angle

NASA Astrophysics Data System (ADS)

Murakami, Hiroki; Seki, Hirokazu; Minakata, Hideaki; Tadakuma, Susumu

This paper describes a novel operationality improvement control for electric power assisted wheelchairs. “Electric power assisted wheelchair” which assists 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 performance of the straight and circular road driving must be further improved because the two wheels drive independently. This paper proposes a novel operationality improvement control by fuzzy algorithm to realize the stable driving on straight and circular roads. The suitable assisted torque of the right and left wheels is determined by fuzzy algorithm based on the posture angular velocity, the posture angle of the wheelchair, the human input torque proportion and the total human torque of the right and left wheels. Some experiments on the practical roads show the effectiveness of the proposed control system.

Fast instantaneous center of rotation estimation algorithm for a skied-steered robot

NASA Astrophysics Data System (ADS)

Kniaz, V. V.

2015-05-01

Skid-steered robots are widely used as mobile platforms for machine vision systems. However it is hard to achieve a stable motion of such robots along desired trajectory due to an unpredictable wheel slip. It is possible to compensate the unpredictable wheel slip and stabilize the motion of the robot using visual odometry. This paper presents a fast optical flow based algorithm for estimation of instantaneous center of rotation, angular and longitudinal speed of the robot. The proposed algorithm is based on Horn-Schunck variational optical flow estimation method. The instantaneous center of rotation and motion of the robot is estimated by back projection of optical flow field to the ground surface. The developed algorithm was tested using skid-steered mobile robot. The robot is based on a mobile platform that includes two pairs of differential driven motors and a motor controller. Monocular visual odometry system consisting of a singleboard computer and a low cost webcam is mounted on the mobile platform. A state-space model of the robot was derived using standard black-box system identification. The input (commands) and the output (motion) were recorded using a dedicated external motion capture system. The obtained model was used to control the robot without visual odometry data. The paper is concluded with the algorithm quality estimation by comparison of the trajectories estimated by the algorithm with the data from motion capture system.

14 CFR Appendix C to Part 23 - Basic Landing Conditions

Code of Federal Regulations, 2011 CFR

2011-01-01

... 14 Aeronautics and Space 1 2011-01-01 2011-01-01 false Basic Landing Conditions C Appendix C to... to Part 23—Basic Landing Conditions [C23.1 Basic landing conditions] Condition Tail wheel type Level landing Tail-down landing Nose wheel type Level landing with inclined reactions Level landing with nose...

Wind wheel electric power generator

NASA Technical Reports Server (NTRS)

Kaufman, J. W. (Inventor)

1980-01-01

Wind wheel electric power generator apparatus includes a housing rotatably mounted upon a vertical support column. Primary and auxiliary funnel-type, venturi ducts are fixed onto the housing for capturing wind currents and conducting to a bladed wheel adapted to be operatively connected with the generator apparatus. Additional air flows are also conducted onto the bladed wheel; all of the air flows positively effecting rotation of the wheel in a cumulative manner. The auxiliary ducts are disposed at an acute angle with respect to the longitudinal axis of the housing, and this feature, together with the rotatability of the housing and the ducts, permits capture of wind currents within a variable directional range.

A new primary mobility tool for the visually impaired: A white cane-adaptive mobility device hybrid.

PubMed

Rizzo, John-Ross; Conti, Kyle; Thomas, Teena; Hudson, Todd E; Wall Emerson, Robert; Kim, Dae Shik

2017-05-16

This article describes pilot testing of an adaptive mobility device-hybrid (AMD-H) combining properties of two primary mobility tools for people who are blind: the long cane and adaptive mobility devices (AMDs). The long cane is the primary mobility tool used by people who are blind and visually impaired for independent and safe mobility and AMDs are adaptive devices that are often lightweight frames approximately body width in lateral dimension that are simply pushed forward to clear the space in front of a person. The prototype cane built for this study had a wing apparatus that could be folded around the shaft of a cane but when unfolded, deployed two wheeled wings 25 cm (9.8 in) to each side of the canetip. This project explored drop-off and obstacle detection for 6 adults with visual impairment using the deployed AMD-H and a standard long cane. The AMD-H improved obstacle detection overall, and was most effective for the smallest obstacles (2 and 6 inch diameter). The AMD-H cut the average drop off threshold from 1.79 inches (4.55 cm) to .96 inches (2.44 cm). All participants showed a decrease in drop off detection threshold and an increase in detection rate (13.9% overall). For drop offs of 1 in (2.54 cm) and 3 in (7.62 cm), all participants showed large improvements with the AMD-H, ranging from 8.4 to 50%. The larger drop offs of 5 in (12.7 cm) and 7 in (17.8 cm) were well detected by both types of canes.

Science on Wheels

ERIC Educational Resources Information Center

Savitz, Maxine L.

1973-01-01

A science program was developed which is based on a mobile laboratory containing scientific experiments in biology, chemistry, physics, applied science, and mathematics. Discussion and experiments differ from the normal classroom setting as they utilize small groups and center around the relationship of modern science and technology of the urban…

Engineering report. Part 3: NASA lightweight wheel and brake sub-system. Lightweight brake development. [for application to space shuttle

NASA Technical Reports Server (NTRS)

Bok, L. D.

1973-01-01

The development of light weight wheel and brake systems designed to meet the space shuttle type requirements was investigated. The study includes the use of carbon graphite composite and beryllium as heat sink materials and the compatibility of these heat sink materials with the other structural components of the wheel and brake.

Development of public health program for type 1 diabetes in a university community: preliminary evaluation of behavioural change wheel.

PubMed

Nwose, Ezekiel Uba; Digban, K A; Anyasodor, A E; Bwititi, P T; Richards, R S; Igumbor, E O

2017-10-23

Diabetes mellitus, including type 1 is a global public health problem among the young persons. While public health campaign and screening program is a potential strategy, but communication skills, knowledge and opinion of the healthcare personnel are indicated as variables that can impact patient's education, which will lead to better outcome of care. Thus, in designing or planning a program for public health, workforce development considers opinion and behavioural change wheel of prospective personnel. The purpose of this preliminary study was to evaluate if a university academic department has the behavioural change wheel to function as workforce infrastructure for an envisioned program. Survey of knowledge, attitude and practice (KAP) of a university community regarding diabetes type 1 was performed. The KAP were translated into behavioural change wheel comprising capacity, motivation and opportunity (CMO). There are baseline indications of the behavioural change wheel potential of the public health department to run a T1D screening program. The number of participants who knew someone with T1D was significantly higher than the subgroup with no such knowledge (p<0.0004) and this improved when age factor is considered (p<0.00005). While the public health department of a university community has the behavioural change wheel or CMO to develop a workforce infrastructure for T1D screening program, the experience that comes with age of lecturers will be an important factor to enable such program to succeed.

A Low Cost Mobile Robot Based on Proportional Integral Derivative (PID) Control System and Odometer for Education

NASA Astrophysics Data System (ADS)

Haq, R.; Prayitno, H.; Dzulkiflih; Sucahyo, I.; Rahmawati, E.

2018-03-01

In this article, the development of a low cost mobile robot based on PID controller and odometer for education is presented. PID controller and odometer is applied for controlling mobile robot position. Two-dimensional position vector in cartesian coordinate system have been inserted to robot controller as an initial and final position. Mobile robot has been made based on differential drive and sensor magnetic rotary encoder which measured robot position from a number of wheel rotation. Odometry methode use data from actuator movements for predicting change of position over time. The mobile robot is examined to get final position with three different heading angle 30°, 45° and 60° by applying various value of KP, KD and KI constant.

Benefit of "Push-pull" Locomotion for Planetary Rover Mobility

NASA Technical Reports Server (NTRS)

Creager, Colin M.; Moreland, Scott Jared; Skonieczny, K.; Johnson, K.; Asnani, V.; Gilligan, R.

2011-01-01

As NASAs exploration missions on planetary terrains become more aggressive, a focus on alternative modes of locomotion for rovers is necessary. In addition to climbing steep slopes, the terrain in these extreme environments is often unknown and can be extremely hard to traverse, increasing the likelihood of a vehicle or robot becoming damaged or immobilized. The conventional driving mode in which all wheels are either driven or free-rolling is very efficient on flat hard ground, but does not always provide enough traction to propel the vehicle through soft or steep terrain. This paper presents an alternative mode of travel and investigates the fundamental differences between these locomotion modes. The methods of push-pull locomotion discussed can be used with articulated wheeled vehicles and are identified as walking or inchinginch-worming. In both cases, the braked non-rolling wheels provide increased thrust. An in-depth study of how soil reacts under a rolling wheel vs. a braked wheel was performed by visually observing the motion of particles beneath the surface. This novel technique consists of driving or dragging a wheel in a soil bin against a transparent wall while high resolution, high-rate photographs are taken. Optical flow software was then used to determine shearing patterns in the soil. Different failure modes were observed for the rolling and braked wheel cases. A quantitative comparison of inching vs. conventional driving was also performed on a full-scale vehicle through a series of drawbar pull tests in the Lunar terrain strength simulant, GRC-1. The effect of tire stiffness was also compared; typically compliant tires provide better traction when driving in soft soil, however its been observed that rigid wheels may provide better thrust when non-rolling. Initial tests indicate up to a possible 40 increase in pull force capability at high slip when inching vs. rolling.

Wheeled and standard walkers in Parkinson's disease patients with gait freezing.

PubMed

Cubo, Esther; Moore, Charity G; Leurgans, Sue; Goetz, Christopher G

2003-10-01

Compare the efficacy of two walking assistance devices (wheeled walker and standard walker) to unassisted walking for patients with PD and gait freezing. Although numerous walking devices are used clinically, their relative effects on freezing and walking speed have never been systematically tested. Nineteen PD patients (14 non-demented) walked under three conditions in randomized order: unassisted walking, standard walker, and wheeled walker. Patients walked up to three times in each condition through a standard course that included rising from a chair, walking through a doorway, straightway walking, pivoting, and return. Total walking time, freezing time and number of freezes were compared for the three conditions using mixed models (walking time) and Friedman's test (freezing). The wheeled walker was further studied by comparing the effect of an attached laser that projected a bar of light on the floor as a visual walking cue. Use of either type of device significantly slowed walking compared to unassisted walking. Neither walker reduced any index of freezing, nor the laser attachment offered any advantage to the wheeled walker. The standard walker increased freezing, and the wheeled walker had no effect on freezing. Among the non-demented subjects (n=14), the same patterns occurred, although the walking speed was less impaired by the wheeled walker than the standard walker in this group. Though walkers may stabilize patients and increase confidence, PD patients walk more slowly when using them, without reducing freezing. Because the wheeled walker was intermediate for walking time and does not aggravate freezing, if walkers are used for these subjects, this type of walker should be favored.

Influence of manual therapy on functional mobility after joint injury in a rat model.

PubMed

Ruhlen, Rachel L; Snider, Eric J; Sargentini, Neil J; Worthington, Bart D; Singh, Vineet K; Pazdernik, Vanessa K; Johnson, Jane C; Degenhardt, Brian F

2013-10-01

Animal models can be used to investigate manual therapy mechanisms, but testing manipulation in animal models is problematic because animals cannot directly report their pain. To develop a rat model of inflammatory joint injury to test the efficacy of manual therapy in reducing nociception and restoring function. The authors induced acute inflammatory joint injury in rats by injecting carrageenan into the ankle and then measured voluntary running wheel activity in treated and untreated rats. Treatments included manual therapy applied to the ankle and knee of the injured limb and several analgesic medications (eg, morphine, ketorolac, prednisone). Intra-articular injection of carrageenan to the ankle produced significant swelling (diameter of the ankle increased by 64% after injection; P=.004) and a robust reduction in voluntary running wheel activity (running distance reduced by 91% compared with controls; P<.001). Injured rats gradually returned to running levels equal to controls over 10 days. Neither manual therapy nor analgesic medications increased running wheel activity relative to untreated rats. Voluntary running wheel activity appears to be an appropriate functional measure to evaluate the impact of an acute inflammatory joint injury. However, efforts to treat the injury did not restore running relative to untreated rats.

Evaluating Isolation Behaviors by Nurses Using Mobile Computer Workstations at the Bedside.

PubMed

Beam, Elizabeth L; Gibbs, Shawn G; Hewlett, Angela L; Iwen, Peter C; Nuss, Suzanne L; Smith, Philip W

2016-09-01

This secondary analysis from a larger mixed methods study with a sequential explanatory design investigates the clinical challenges for nurses providing patient care, in an airborne and contact isolation room, while using a computer on wheels for medication administration in a simulated setting. Registered nurses, who regularly work in clinical care at the patient bedside, were recruited as study participants in the simulation and debriefing experience. A live volunteer acted as the standardized patient who needed assessment and intravenous pain medication. The simulation was video recorded in a typical hospital room to observe participating nurses conducting patient care in an airborne and contact isolation situation. Participants then reviewed their performance with study personnel in a formal, audio-recorded debriefing. Isolation behaviors were scored by an expert panel, and the debriefing sessions were analyzed. Considerable variation was found in behaviors related to using a computer on wheels while caring for a patient in isolation. Currently, no nursing care guidelines exist on the use of computers on wheels in an airborne and contact isolation room. Specific education is needed on nursing care processes for the proper disinfection of computers on wheels and the reduction of the potential for disease transmission from environmental contamination.

Classroom on Wheels.

ERIC Educational Resources Information Center

Murfreesboro City Schools, TN.

Designed for 3- and 4-year-old disadvantaged children and their parents, a mobile unit consisting of a renovated school bus turned classroom is described which travels to three areas daily for a 2-hour period. The program for children is designed primarily for developmental skills--visual, sensory, auditory, and cognitive. Activities emphasize…

Worktable on Wheels.

ERIC Educational Resources Information Center

Glockner, Mary

1969-01-01

This article briefly describes the function and features of the Smith Circular Learning Station used in Chattanooga, Tennessee's Head Start and Follow Through program. The stations are used in place of traditional rows of classroom desks. Each station consists of a mobile worktable and a set of stackable chairs. Children are allowed to move about…

Depot Maintenance: Improved Strategic Planning Needed to Ensure That Army and Marine Corps Depots Can Meet Future Maintenance Requirements

DTIC Science & Technology

2009-09-01

System, and Sidewinder, as well as mobile electric power generation equipment Red River Texarkana , Texas Bradley Fighting Vehicle, tactical wheeled...Depot, Corpus Christi, Texas; Letterkenny Army Depot, Chambersburg, Pennsylvania; Red River Army Depot, Texarkana , Texas; and Tobyhanna Army Depot

76 FR 66048 - 36(b)(1) Arms Sales Notification

Federal Register 2010, 2011, 2012, 2013, 2014

2011-10-25

.... (iii) Description and Quantity or Quantities of Articles or Services under Consideration for Purchase... High Mobility Multi-Purpose Wheeled Vehicles (HMMWVs), 1 lot AN/MPQ- 64F1 SENTINEL Radar software, 290...-Launched Advanced Medium Range Air-to-Air Missile (SL-AMRAAM) software to support Oman's Ground Based Air...

30 CFR 18.20 - Quality of material, workmanship, and design.

Code of Federal Regulations, 2013 CFR

2013-07-01

..., circuits, arrangements, or combinations of components and materials cannot be foreseen, MSHA reserves the... provided on each mobile machine that travels at a speed greater than 2.5 miles per hour. (f) Brakes shall be provided for each wheel-mounted machine, unless design of the driving mechanism will preclude...

30 CFR 18.20 - Quality of material, workmanship, and design.

Code of Federal Regulations, 2014 CFR

2014-07-01

..., circuits, arrangements, or combinations of components and materials cannot be foreseen, MSHA reserves the... provided on each mobile machine that travels at a speed greater than 2.5 miles per hour. (f) Brakes shall be provided for each wheel-mounted machine, unless design of the driving mechanism will preclude...

30 CFR 18.20 - Quality of material, workmanship, and design.

Code of Federal Regulations, 2012 CFR

2012-07-01

..., circuits, arrangements, or combinations of components and materials cannot be foreseen, MSHA reserves the... provided on each mobile machine that travels at a speed greater than 2.5 miles per hour. (f) Brakes shall be provided for each wheel-mounted machine, unless design of the driving mechanism will preclude...

Design of automatic mobile trolley using ultrasonic sensors

NASA Astrophysics Data System (ADS)

Dodi Suryanto, Eka; Siagian, Hendrik; Perangin-Angin, Despaleri; Sashanti, Rahayu; Yogen, Suthes

2018-04-01

An automatic mobile trolley was a prototype of wheel robot that serves as a trolley or shopping cart. This paper proposed an automatic mobile trolley using ultrasonic sensors. It can follow human movement automatically. It did not need to be encouraged or withdrawn. It would make an easier shopping for people as customers. The trolley controlled by a microcontroller module unit. It can stop, turn right, turn left, forward and backward. It can follow wherever they go, during they were in range. Based on the test results, the trolley succeeded to move forward by 80%, move backward 80%, turn left, 70%, turn right 70%, and stop 80%.

Metering Wheel-Wire Track Wire Boom Deployment Mechanism

NASA Technical Reports Server (NTRS)

Granoff, Mark S.

2014-01-01

The NASA MMS Spin Plane Double Probe (SDP) Deployer utilizes a helical path, rotating Metering Wheel and a spring loaded Wire "Holding" Track to pay out a "fixed end" 57 meter x 1.5 mm diameter Wire Boom stored between concentric storage cylinders. Unlike rotating spool type storage devices, the storage cylinders remain stationary, and the boom wire is uncoiled along the length of the cylinder via the rotation of the Metering Wheel. This uncoiling action avoids the need for slip-ring contacts since the ends of the wire can remain stationary. Conventional fixed electrical connectors (Micro-D type) are used to terminate to operational electronics.

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.

Conditioned taste avoidance induced by forced and voluntary wheel running in rats.

PubMed

Forristall, J R; Hookey, B L; Grant, V L

2007-03-01

Voluntary exercise by rats running in a freely rotating wheel (free wheel) produces conditioned taste avoidance (CTA) of a flavored solution consumed before running [e.g., Lett, B.T., Grant, V.L., 1996. Wheel running induces conditioned taste aversion in rats trained while hungry and thirsty. Physiol. Behav. 59, 699-702]. Forced exercise, swimming or running, also produces CTA in rats [e.g., Masaki, T., Nakajima, S., 2006. Taste aversion induced by forced swimming, voluntary running, forced running, and lithium chloride injection treatments. Physiol. Behav. 88, 411-416]. Energy expenditure may be the critical factor in producing such CTA. If so, forced running in a motorized running wheel should produce CTA equivalent to that produced by a similar amount of voluntary running. In two experiments, we compared forced running in a motorized wheel with voluntary running in a free wheel. Mean distance run over 30 min was equated as closely as possible in the two apparatuses. Both types of exercise produced CTA relative to sedentary, locked-wheel controls. However, voluntary running produced greater CTA than forced running. We consider differences between running in the free and motorized wheels that may account for the differences in strength of CTA.

Mapping the formation areas of giant molybdenum blue clusters: a spectroscopic study

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

Botar, Bogdan; Ellern, Arkady; Kogerler, Paul

2012-05-18

The self-assembly of soluble molybdenum blue species from simple molybdate solutions has primarily been associated with giant mixed-valent wheel-shaped cluster anions, derived from the {MoV/VI154/176} archetypes, and a {MoV/VI368} lemon-shaped cluster. The combined use of Raman spectroscopy and kinetic precipitation as self-assembly monitoring techniques and single-crystal X-ray diffraction is key to mapping the realm of molybdenum blue species by establishing spherical {MoV/VI102}-type Keplerates as an important giant molybdenum blue-type species. We additionally rationalize the empirical effect of reducing agent concentration on the formation of all three relevant skeletal types: wheel, lemon and spheres. Whereas both wheels and the lemon-shaped {MoV/VI368}more » cluster are obtained from weakly reduced molybdenum blue solutions, considerably higher reduced solutions lead to {MoV/VI102}-type Keplerates.« less

A method for improved accuracy in three dimensions for determining wheel/rail contact points

NASA Astrophysics Data System (ADS)

Yang, Xinwen; Gu, Shaojie; Zhou, Shunhua; Zhou, Yu; Lian, Songliang

2015-11-01

Searching for the contact points between wheels and rails is important because these points represent the points of exerted contact forces. In order to obtain an accurate contact point and an in-depth description of the wheel/rail contact behaviours on a curved track or in a turnout, a method with improved accuracy in three dimensions is proposed to determine the contact points and the contact patches between the wheel and the rail when considering the effect of the yaw angle and the roll angle on the motion of the wheel set. The proposed method, with no need of the curve fitting of the wheel and rail profiles, can accurately, directly, and comprehensively determine the contact interface distances between the wheel and the rail. The range iteration algorithm is used to improve the computation efficiency and reduce the calculation required. The present computation method is applied for the analysis of the contact of rails of CHINA (CHN) 75 kg/m and wheel sets of wearing type tread of China's freight cars. In addition, it can be proved that the results of the proposed method are consistent with that of Kalker's program CONTACT, and the maximum deviation from the wheel/rail contact patch area of this two methods is approximately 5%. The proposed method, can also be used to investigate static wheel/rail contact. Some wheel/rail contact points and contact patch distributions are discussed and assessed, wheel and rail non-worn and worn profiles included.

GOAT (goes over all terrain) vehicle: a scaleable robotic vehicle

NASA Astrophysics Data System (ADS)

Dodson, Michael G.; Owsley, Stanley L.; Moorehead, Stewart J.

2003-09-01

Many of the potential applications of mobile robots require a small to medium sized vehicle that is capable of traversing large obstacles and rugged terrain. Search and rescue operations require a robot small enough to drive through doorways, yet capable enough to surmount rubble piles and stairs. This paper presents the GOAT (Goes Over All Terrain) vehicle, a medium scale robot which incorporates a novel configuration which puts the drive wheels on the ends of actuated arms. This allows GOAT to adjust body height and posture and combines the benefits of legged locomotion with the ease of wheeled driving. The paper presents the design of the GOAT and the results of prototype construction and initial testing.

Navigation system for autonomous mapper robots

NASA Astrophysics Data System (ADS)

Halbach, Marc; Baudoin, Yvan

1993-05-01

This paper describes the conception and realization of a fast, robust, and general navigation system for a mobile (wheeled or legged) robot. A database, representing a high level map of the environment is generated and continuously updated. The first part describes the legged target vehicle and the hexapod robot being developed. The second section deals with spatial and temporal sensor fusion for dynamic environment modeling within an obstacle/free space probabilistic classification grid. Ultrasonic sensors are used, others are suspected to be integrated, and a-priori knowledge is treated. US sensors are controlled by the path planning module. The third part concerns path planning and a simulation of a wheeled robot is also presented.

Analysis of wheel rim - Material and manufacturing aspects

NASA Astrophysics Data System (ADS)

Misra, Sheelam; Singh, Abhiraaj; James, Eldhose

2018-05-01

The tire in an automobile is supported by the rim of the wheel and its shape and dimensions should be adjusted to accommodate a specified tire. In this study, a tire of car wheel rim belonging to the disc wheel category is considered. Design is an important industrial operation used to define and specify the quality of the product. The design and modelling reduces the risk of damage involved in the manufacturing process. The design performed on this wheel rim is done on modelling software. After designing the model, it is imported for analysis purposes. The analysis software is used to calculate the different types of force, stresses, torque, and pressures acting upon the rim of the wheel and it reduces the time spent by a human for mathematical calculations. The analysis carried out considers two different materials namely structural steel and aluminium. Both materials are analyzed and their performance is noted.

Stocks and flows of lead-based wheel weights in the United States

USGS Publications Warehouse

Bleiwas, Donald I.

2006-01-01

Lead is used in many widely known applications, such as automobile batteries and radiation shielding. Another lesser known, but long-term, use of lead is in automotive vehicle wheel weights. Lead weights have been used to balance wheels since the 1930s because of its high specific gravity, low relative cost, and its malleability. Out-of-balance tires tend to 'cup' and vibrate and as a result cause excessive wear on tires and vehicle suspension components and result in compromised handling, especially at high speeds. The mass, number, and style of weights needed to balance a wheel depend on the tire's size and weight and on the type and condition of the wheels (rims) on the vehicle. This study addresses an accounting of the stocks and flows of lead contained in lead wheel weights from their manufacture, through use, dissipation, and recycling, and environmental issues associated with the use of lead.

On the dynamic response at the wheel axle of a pneumatic tire

NASA Astrophysics Data System (ADS)

Kung, L. E.; Soedel, W.; Yang, T. Y.

1986-06-01

A method for calculating the steady state displacement response and force transmission at the wheel axle of a pneumatic tire-suspension system due to a steady state force or displacement excitation at the tire to ground contact point is developed. The method requires the frequency responses (or receptances)_of both tire-wheel and suspension units. The frequency response of the tire-wheel unit is obtained by using the modal expansion method. The natural frequencies and mode shapes of the tire-wheel unit are obtained by using a geometrically non-linear, ring type, thin shell finite element of laminate composite. The frequency response of the suspension unit is obtained analytically. These frequency responses are used to calculate the force-input and the displacement-input responses at the wheel axle. This method allows the freedom of designing a vehicle and its tires independently and still achieving optimum dynamic performance.

Mobility analysis, simulation, and scale model testing for the design of wheeled planetary rovers

NASA Technical Reports Server (NTRS)

Lindemann, Randel A.; Eisen, Howard J.

1993-01-01

The use of computer based techniques to model and simulate wheeled rovers on rough natural terrains is considered. Physical models of a prototype vehicle can be used to test the correlation of the simulations in scaled testing. The computer approaches include a quasi-static planar or two dimensional analysis and design tool based on the traction necessary for the vehicle to have imminent mobility. The computer program modeled a six by six wheel drive vehicle of original kinematic configuration, called the Rocker Bogie. The Rocker Bogie was optimized using the quasi-static software with respect to its articulation parameters prior to fabrication of a prototype. In another approach used, the dynamics of the Rocker Bogie vehicle in 3-D space was modeled on an engineering workstation using commercial software. The model included the complex and nonlinear interaction of the tire and terrain. The results of the investigation yielded numerical and graphical results of the rover traversing rough terrain on the earth, moon, and Mars. In addition, animations of the rover excursions were also generated. A prototype vehicle was then used in a series of testbed and field experiments. Correspondence was then established between the computer models and the physical model. The results indicated the utility of the quasi-static tool for configurational design, as well as the predictive ability of the 3-D simulation to model the dynamic behavior of the vehicle over short traverses.

Grinding aspheric and freeform micro-optical molds

NASA Astrophysics Data System (ADS)

Tohme, Yazid E.

2007-02-01

Fueled by the need for better performing optics, glass optics are now replacing plastic optics in many industrial and consumer electronic devices. One of these devices is the mobile phone camera. The optical sub-assembly in a mobile phone includes several micro lenses that are spherical and/or aspherical in shape and require form tolerances in the submicron range. These micro glass lenses are mass produced by a replication process known as glass press molding. The process entails the compression of a glass gob between two precise optical quality molds at an elevated temperature, usually near the transition temperature of the glass material. The elevated forces and temperatures required in the glass molding process limits the materials of the molds to very tough materials such as tungsten carbide or silicon carbide. These materials can withstand large pressing forces at high temperatures without any significant deformation. These materials offer great mechanical properties for glass press molding but they are also a challenge to machine to submicron accuracy. The work in this paper discusses a deterministic micro grinding manufacturing process referred to as wheel normal grinding, which is utilized to produce these optical quality molds. Wheel normal grinding is more accurate and more deterministic than most other grinding techniques and can produce molds to the form and finish tolerances required for optical molding. This method relies on the ability to recognize and compensate for grinding wheel wear and machine repeatable errors. Results will be presented to illustrate the accuracy of this micro grinding technique.

Voluntary wheel running increases satellite cell abundance and improves recovery from disuse in gastrocnemius muscles from mice.

PubMed

Brooks, Matthew J; Hajira, Ameena; Mohamed, Junaith S; Alway, Stephen E

2018-06-01

Reloading of atrophied muscles after hindlimb suspension unloading (HSU) can induce injury and prolong recovery. Low-impact exercise, such as voluntary wheel running, has been identified as a nondamaging rehabilitation therapy in rodents, but its effects on muscle function, morphology, and satellite cell activity after HSU are unclear. This study tested the hypothesis that low-impact wheel running would increase satellite cell proliferation and improve recovery of muscle structure and function after HSU in mice. Young adult male and female C57BL/6 mice ( n = 6/group) were randomly placed into five groups. These included HSU without recovery (HSU), normal ambulatory recovery for 14 days after HSU (HSU+NoWR), and voluntary wheel running recovery for 14 days after HSU (HSU+WR). Two control groups were used: nonsuspended mouse cage controls (Control) and voluntary wheel running controls (ControlWR). Satellite cell activation was evaluated by providing mice 5-bromo-2'-deoxyuridine (BrdU) in their drinking water. As expected, HSU significantly reduced in vivo maximal force, decreased in vivo fatigability, and decreased type I and IIa myosin heavy chain (MHC) abundance in plantarflexor muscles. HSU+WR mice significantly improved plantarflexor fatigue resistance, increased type I and IIa MHC abundance, increased fiber cross-sectional area, and increased the percentage of type I and IIA muscle fibers in the gastrocnemius muscle. HSU+WR mice also had a significantly greater percentage of BrdU-positive and Pax 7-positive nuclei inside muscle fibers and a greater MyoD-to-Pax 7 protein ratio compared with HSU+NoWR mice. The mechanotransduction protein Yes-associated protein (YAP) was elevated with reloading after HSU, but HSU+WR mice had lower levels of the inactive phosphorylated YAP serine127 , which may have contributed to increased satellite cell activation with reloading after HSU. These results indicate that voluntary wheel running increased YAP signaling and satellite cell activity after HSU and this was associated with improved recovery. NEW & NOTEWORTHY Although satellite cell involvement in muscle remodeling has been challenged, the data in this study suggest that voluntary wheel running increased satellite cell activity and suppressed Yes-associated protein (YAP) protein relative to no wheel running and this was associated with improved muscle recovery of force, fatigue resistance, expression of type I myosin heavy chain, and greater fiber cross-sectional area after disuse.

Locomotor activity and gait in aged mice deficient for type IX collagen

PubMed Central

Costello, Kerry E.; Guilak, Farshid; Griffin, Timothy M.

2010-01-01

Osteoarthritis (OA) is a risk factor for physical inactivity and impaired mobility, but it is not well understood how these locomotor behaviors are affected by the age of onset of OA and disease severity. Male mice homozygous for a Col9a1 gene inactivation (Col9a1−/−) develop early onset knee OA, increased tactile pain sensitivity, and gait alterations by 9 mo of age. We hypothesized that aged Col9a1−/− mice would reduce joint pain by adopting locomotor behaviors that reduce both the magnitude and daily frequency of joint loading. We tested this hypothesis by evaluating gait and spontaneous locomotor activity in 15- to 17-mo-old male Col9a1−/− (n = 5) and Col9a1+/+(WT) (n = 5) mice using well-controlled measures of voluntary activity in overground and running wheel conditions, as well as studies of gait in a velocity-controlled treadmill. We found no difference due to genotype in freely chosen locomotor velocity, stride frequency, hindfoot duty factor, dark phase activity time, or dark-phase travel distance during overground, running wheel, or speed-matched treadmill locomotion. Interpretation of these findings is potentially confounded by the observation that WT mice have greater knee OA than Col9a1−/− mice in the lateral tibial plateau by 17 mo of age. When accounting for individual differences in knee OA, functional locomotor impairments in aged Col9a1−/− and WT mice are manifested as reductions in total locomotor activity levels (e.g., both distance traveled and time active), particularly for wheel running. These results support the concept that current disease status, rather than age of disease onset, is the primary determinant of impaired locomotor activity with aging. PMID:20360435

A global approach to kinematic path planning to robots with holonomic and nonholonomic constraints

NASA Technical Reports Server (NTRS)

Divelbiss, Adam; Seereeram, Sanjeev; Wen, John T.

1993-01-01

Robots in applications may be subject to holonomic or nonholonomic constraints. Examples of holonomic constraints include a manipulator constrained through the contact with the environment, e.g., inserting a part, turning a crank, etc., and multiple manipulators constrained through a common payload. Examples of nonholonomic constraints include no-slip constraints on mobile robot wheels, local normal rotation constraints for soft finger and rolling contacts in grasping, and conservation of angular momentum of in-orbit space robots. The above examples all involve equality constraints; in applications, there are usually additional inequality constraints such as robot joint limits, self collision and environment collision avoidance constraints, steering angle constraints in mobile robots, etc. The problem of finding a kinematically feasible path that satisfies a given set of holonomic and nonholonomic constraints, of both equality and inequality types is addressed. The path planning problem is first posed as a finite time nonlinear control problem. This problem is subsequently transformed to a static root finding problem in an augmented space which can then be iteratively solved. The algorithm has shown promising results in planning feasible paths for redundant arms satisfying Cartesian path following and goal endpoint specifications, and mobile vehicles with multiple trailers. In contrast to local approaches, this algorithm is less prone to problems such as singularities and local minima.

Development of Android Based Powered Intelligent Wheelchair for Quadriplegic Persons

NASA Astrophysics Data System (ADS)

Gupta, Ashutosh; Ghosh, Tathagata; Kumar, Pradeep; Bhawna, Shruthi. S.

2017-08-01

Several surveys give us the view that both children and adults benefit substantially from access towards independent mobility. With the inventions of technology, no individuals are satisfied with traditional manual operated machines. To accommodate population, researchers are using technology, originally developed for mobile robots to create ‘intelligent wheelchairs’. It’s a major challenge for quadriplegic persons as they really find it difficult to manipulate powered wheelchair during the activities of their daily living. As the Smartphone era has evolved with innovative android based applications, engineers are improving and trying to make such machines simple and cheap to the next level. In this paper, we present a development of android based powered intelligent wheelchair to assist the quadriplegic person by making them self sufficient in controlling the wheelchair. The wheels of the chair can be controlled by the voice or gesture movement or by touching the screen of the android app by the challenged persons. The system uses the Bluetooth communication to interface the microcontroller and the inbuilt sensors in the android Smartphone. According to the commands received from android phone, the kinematics of the wheels are controlled.

The Dynamic Tensile Behavior of Railway Wheel Steel at High Strain Rates

NASA Astrophysics Data System (ADS)

Jing, Lin; Han, Liangliang; Zhao, Longmao; Zhang, Ying

2016-11-01

The dynamic tensile tests on D1 railway wheel steel at high strain rates were conducted using a split Hopkinson tensile bar (SHTB) apparatus, compared to quasi-static tests. Three different types of specimens, which were machined from three different positions (i.e., the rim, web and hub) of a railway wheel, were prepared and examined. The rim specimens were checked to have a higher yield stress and ultimate tensile strength than those web and hub specimens under both quasi-static and dynamic loadings, and the railway wheel steel was demonstrated to be strain rate dependent in dynamic tension. The dynamic tensile fracture surfaces of all the wheel steel specimens are cup-cone-shaped morphology on a macroscopic scale and with the quasi-ductile fracture features on the microscopic scale.

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

Reister, D.B.; Pin, F.G.

This paper addresses the problem of time-optional motions for a mobile platform in a planar environment. The platform has two non-steerable independently driven wheels. The overall mission of the robot is expressed in terms of a sequence of via points at which the platform must be at rest in a given configuration (position and orientation). The objective is to plan time-optimal trajectories between these configurations assuming an unobstructed environment. Using Pontryagin's maximum principle (PMP), we formally demonstrate that all time optimal motions of the platform for this problem occur for bang-bang controls on the wheels (at each instant, the accelerationmore » on each wheel is either at its upper or lower limit). The PMP, however, only provides necessary conditions for time optimality. To find the time optimal robot trajectories, we first parameterize the bang-bang trajectories using the switch times on the wheels (the times at which the wheel accelerations change sign). With this parameterization, we can fully search the robot trajectory space and find the switch times that will produce particular paths to a desired final configuration of the platform. We show numerically that robot trajectories with three switch times (two on one wheel, one on the other) can reach any position, while trajectories with four switch times can reach any configuration. By numerical comparison with other trajectories involving similar or greater numbers of switch times, we then identify the sets of time-optimal trajectories. These are uniquely defined using ranges of the parameters, and consist of subsets of trajectories with three switch times for the problem when the final orientation of the robot is not specified, and four switch times when a full final configuration is specified. We conclude with a description of the use of the method for trajectory planning for one of our robots.« less

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

Reister, D.B.; Pin, F.G.

This paper addresses the problem of time-optional motions for a mobile platform in a planar environment. The platform has two non-steerable independently driven wheels. The overall mission of the robot is expressed in terms of a sequence of via points at which the platform must be at rest in a given configuration (position and orientation). The objective is to plan time-optimal trajectories between these configurations assuming an unobstructed environment. Using Pontryagin`s maximum principle (PMP), we formally demonstrate that all time optimal motions of the platform for this problem occur for bang-bang controls on the wheels (at each instant, the accelerationmore » on each wheel is either at its upper or lower limit). The PMP, however, only provides necessary conditions for time optimality. To find the time optimal robot trajectories, we first parameterize the bang-bang trajectories using the switch times on the wheels (the times at which the wheel accelerations change sign). With this parameterization, we can fully search the robot trajectory space and find the switch times that will produce particular paths to a desired final configuration of the platform. We show numerically that robot trajectories with three switch times (two on one wheel, one on the other) can reach any position, while trajectories with four switch times can reach any configuration. By numerical comparison with other trajectories involving similar or greater numbers of switch times, we then identify the sets of time-optimal trajectories. These are uniquely defined using ranges of the parameters, and consist of subsets of trajectories with three switch times for the problem when the final orientation of the robot is not specified, and four switch times when a full final configuration is specified. We conclude with a description of the use of the method for trajectory planning for one of our robots.« less

Conversion and control of an all-terrain vehicle for use as an autonomous mobile robot

NASA Astrophysics Data System (ADS)

Jacob, John S.; Gunderson, Robert W.; Fullmer, R. R.

1998-08-01

A systematic approach to ground vehicle automation is presented, combining low-level controls, trajectory generation and closed-loop path correction in an integrated system. Development of cooperative robotics for precision agriculture at Utah State University required the automation of a full-scale motorized vehicle. The Triton Predator 8- wheeled skid-steering all-terrain vehicle was selected for the project based on its ability to maneuver precisely and the simplicity of controlling the hydrostatic drivetrain. Low-level control was achieved by fitting an actuator on the engine throttle, actuators for the left and right drive controls, encoders on the left and right drive shafts to measure wheel speeds, and a signal pick-off on the alternator for measuring engine speed. Closed loop control maintains a desired engine speed and tracks left and right wheel speeds commands. A trajectory generator produces the wheel speed commands needed to steer the vehicle through a predetermined set of map coordinates. A planar trajectory through the points is computed by fitting a 2D cubic spline over each path segment while enforcing initial and final orientation constraints at segment endpoints. Acceleration and velocity profiles are computed for each trajectory segment, with the velocity over each segment dependent on turning radius. Left and right wheel speed setpoints are obtained by combining velocity and path curvature for each low-level timestep. The path correction algorithm uses GPS position and compass orientation information to adjust the wheel speed setpoints according to the 'crosstrack' and 'downtrack' errors and heading error. Nonlinear models of the engine and the skid-steering vehicle/ground interaction were developed for testing the integrated system in simulation. These test lead to several key design improvements which assisted final implementation on the vehicle.

The dynamic compressive behavior and constitutive modeling of D1 railway wheel steel over a wide range of strain rates and temperatures

NASA Astrophysics Data System (ADS)

Jing, Lin; Su, Xingya; Zhao, Longmao

The dynamic compressive behavior of D1 railway wheel steel at high strain rates was investigated using a split Hopkinson pressure bar (SHPB) apparatus. Three types of specimens, which were derived from the different positions (i.e., the rim, web and hub) of a railway wheel, were tested over a wide range of strain rates from 10-3 s-1 to 2.4 × 103 s-1 and temperatures from 213 K to 973 K. Influences of the strain rate and temperature on flow stress were discussed, and rate- and temperature-dependent constitutive relationships were assessed by the Cowper-Symonds model, Johnson-Cook model and a physically-based model, respectively. The experimental results show that the compressive true stress versus true strain response of D1 wheel steel is strain rate-dependent, and the strain hardening rate during the plastic flow stage decreases with the elevation of strain rate. Besides, the D1 wheel steel displays obvious temperature-dependence, and the third-type strain aging (3rd SA) is occurred at the temperature region of 673-973 K at a strain rate of ∼1500 s-1. Comparisons of experimental results with theoretical predictions indicate that the physically-based model has a better prediction capability for the 3rd SA characteristic of the tested D1 wheel steel.

Aerodynamic analysis of an isolated vehicle wheel

NASA Astrophysics Data System (ADS)

Leśniewicz, P.; Kulak, M.; Karczewski, M.

2014-08-01

Increasing fuel prices force the manufacturers to look into all aspects of car aerodynamics including wheels, tyres and rims in order to minimize their drag. By diminishing the aerodynamic drag of vehicle the fuel consumption will decrease, while driving safety and comfort will improve. In order to properly illustrate the impact of a rotating wheel aerodynamics on the car body, precise analysis of an isolated wheel should be performed beforehand. In order to represent wheel rotation in contact with the ground, presented CFD simulations included Moving Wall boundary as well as Multiple Reference Frame should be performed. Sliding mesh approach is favoured but too costly at the moment. Global and local flow quantities obtained during simulations were compared to an experiment in order to assess the validity of the numerical model. Results of investigation illustrates dependency between type of simulation and coefficients (drag and lift). MRF approach proved to be a better solution giving result closer to experiment. Investigation of the model with contact area between the wheel and the ground helps to illustrate the impact of rotating wheel aerodynamics on the car body.

Adams-Based Rover Terramechanics and Mobility Simulator - ARTEMIS

NASA Technical Reports Server (NTRS)

Trease, Brian P.; Lindeman, Randel A.; Arvidson, Raymond E.; Bennett, Keith; VanDyke, Lauren P.; Zhou, Feng; Iagnemma, Karl; Senatore, Carmine

2013-01-01

The Mars Exploration Rovers (MERs), Spirit and Opportunity, far exceeded their original drive distance expectations and have traveled, at the time of this reporting, a combined 29 kilometers across the surface of Mars. The Rover Sequencing and Visualization Program (RSVP), the current program used to plan drives for MERs, is only a kinematic simulator of rover movement. Therefore, rover response to various terrains and soil types cannot be modeled. Although sandbox experiments attempt to model rover-terrain interaction, these experiments are time-intensive and costly, and they cannot be used within the tactical timeline of rover driving. Imaging techniques and hazard avoidance features on MER help to prevent the rover from traveling over dangerous terrains, but mobility issues have shown that these methods are not always sufficient. ARTEMIS, a dynamic modeling tool for MER, allows planned drives to be simulated before commands are sent to the rover. The deformable soils component of this model allows rover-terrain interactions to be simulated to determine if a particular drive path would take the rover over terrain that would induce hazardous levels of slip or sink. When used in the rover drive planning process, dynamic modeling reduces the likelihood of future mobility issues because high-risk areas could be identified before drive commands are sent to the rover, and drives planned over these areas could be rerouted. The ARTEMIS software consists of several components. These include a preprocessor, Digital Elevation Models (DEMs), Adams rover model, wheel and soil parameter files, MSC Adams GUI (commercial), MSC Adams dynamics solver (commercial), terramechanics subroutines (FORTRAN), a contact detection engine, a soil modification engine, and output DEMs of deformed soil. The preprocessor is used to define the terrain (from a DEM) and define the soil parameters for the terrain file. The Adams rover model is placed in this terrain. Wheel and soil parameter files can be altered in the respective text files. The rover model and terrain are viewed in Adams View, the GUI for ARTEMIS. The Adams dynamics solver calls terramechanics subroutines in FORTRAN containing the Bekker-Wong equations.

ATHLETE: A Cargo-Handling Vehicle for Solar System Exploration

NASA Technical Reports Server (NTRS)

Wilcox, Brian H.

2011-01-01

As part of the NASA Exploration Technology Development Program, the Jet Propulsion Laboratory is developing a vehicle called ATHLETE: the All-Terrain Hex-Limbed Extra-Terrestrial Explorer. Each vehicle is based on six wheels at the ends of six multi-degree-of-freedom limbs. Because each limb has enough degrees of freedom for use as a general-purpose leg, the wheels can be locked and used as feet to walk out of excessively soft or other extreme terrain. Since the vehicle has this alternative mode of traversing through or at least out of extreme terrain, the wheels and wheel actuators can be sized for nominal terrain. There are substantial mass savings in the wheel and wheel actuators associated with designing for nominal instead of extreme terrain. These mass savings are comparable-to or larger-than the extra mass associated with the articulated limbs. As a result, the entire mobility system, including wheels and limbs, can be about 25% lighter than a conventional mobility chassis. A side benefit of this approach is that each limb has sufficient degrees-of-freedom to use as a general-purpose manipulator (hence the name "limb" instead of "leg"). Our prototype ATHLETE vehicles have quick-disconnect tool adapters on the limbs that allow tools to be drawn out of a "tool belt" and maneuvered by the limb. A power-take-off from the wheel actuates the tools, so that they can take advantage of the 1+ horsepower motor in each wheel to enable drilling, gripping or other power-tool functions. Architectural studies have indicated that one useful role for ATHLETE in planetary (moon or Mars) exploration is to "walk" cargo off the payload deck of a lander and transport it across the surface. Recent architectural approaches are focused on the concept that the lander descent stage will use liquid hydrogen as a propellant. This is the highest performance chemical fuel, but it requires very large tanks. A natural geometry for the lander is to have a single throttleable rocket engine on the centerline at the bottom, and to have the propellant tanks arranged as compactly as possible around and above that engine, with nearly-straight structural load paths that carry the heavy LO2 tanks as well as the ascent stage or cargo on a top deck. (The requirement for exactly one descent engine stems from the need to avoid symmetry planes in the exhaust plume that can entrain surface particles and loft them up into the system at hypervelocity.) This geometry is especially attractive since abort considerations drive the ascent stage to have as much open space around it as possible, in case the ascent stage needs to fire away from an out-of-control descent stage. These considerations lead to a configuration where the cargo deck of the lander is relatively high off the ground (over 6 meters in current concepts, using a 10-meter diameter launch shroud). These considerations have led some observers to presume that there is a "lander offloading problem". ATHLETE has been demonstrated as a solution to this problem, walking cargo off the high deck. This paper describes the applicability of the ATHLETE concept to exploration of the moon, Mars and even to Near- Earth Objects. Recent field test results for long-range traverse are described, along with plans for testing in the simulated microgravity environment of a NEO.

Flight Test Evaluation of Airborne Tire Pressure Indicating Systems.

DTIC Science & Technology

1979-09-01

System (Concept J, Part I Report) This system employs a wheel This system was the best mounted pressure switch the thought out and implemented state of...which is detected across system of its type with an air gap by a rotating coil excellent electror.ic and passing by a statiorery coil pressure switch designs...Pressure Low tire pressure is sensed by a The supplier of this pressure switch in wheel. hardware built a four wheel Pressure switch shorts secondary

Effects of setting angle on performance of fish-bionic wind wheel

NASA Astrophysics Data System (ADS)

Li, G. S.; Yang, Z. X.; Song, L.; Chen, Q.; Li, Y. B.; Chen, W.

2016-08-01

With the energy crisis and the increasing environmental pollutionmore and more efforts have been made about wind power development. In this paper, a new type of vertical axis named the fish-bionic wind wheel was proposed, and the outline of wind wheel was constructed by curve of Fourier fitting and polynomial equations. This paper attempted to research the relationship between the setting angle and the wind turbine characteristics by computational fluid dynamics (CFD) simulation. The results showed that the setting angle of the fish-bionic wind wheel has some significant effects on the efficiency of the wind turbine, Within the range of wind speed from 13m/s to 15m/s, wind wheel achieves the maximum efficiency when the setting angle is at 37 degree. The conclusion will work as a guideline for the improvement of wind turbine design.

Model Design for Water Wheel Control System of Heumgyeonggaknu

NASA Astrophysics Data System (ADS)

Kim, Sang Hyuk; Ham, Seon Young; Lee, Yong Sam

2016-03-01

Heumgyeonggaknu (????) is powered by a water-hammering-type water wheel. The technique that maintains the constant speed of the water wheel is assumed to be the one used in the Cheonhyeong (???) apparatus in Shui Yun Yi Xiang Tai (???) made by the Northern Song (??) dynasty in the 11th century. We investigated the history of the development and characteristics of the Cheonhyeong apparatus, and we analyzed ways to transmit the power of Heumgyeonggaknu. In addition, we carried out a conceptual design to systematically examine the power control system. Based on the conceptual design, we built a model for a water wheel control system that could be used in experiments by drawing a 3D model and a basic design.

Driving in Parkinson's disease: mobility, accidents, and sudden onset of sleep at the wheel.

PubMed

Meindorfner, Charlotte; Körner, Yvonne; Möller, Jens Carsten; Stiasny-Kolster, Karin; Oertel, Wolfgang Hermann; Krüger, Hans-Peter

2005-07-01

Only few studies have addressed driving ability in Parkinson's disease (PD) to date. However, studies investigating accident proneness of PD patients are urgently needed in the light of motor disability in PD and--particularly--the report of "sleep attacks" at the wheel. We sent a questionnaire about sudden onset of sleep (SOS) and driving behavior to 12,000 PD patients. Subsequently, of 6,620 complete data sets, 361 patients were interviewed by phone. A total of 82% of those 6,620 patients held a driving license, and 60% of them still participated in traffic. Of the patients holding a driving license, 15% had been involved in and 11% had caused at least one accident during the past 5 years. The risk of causing accidents was significantly increased for patients who felt moderately impaired by PD, had an increased Epworth Sleepiness Scale (ESS) score, and had experienced SOS while driving. Sleep attacks at the wheel usually occurred in easy driving situations and resulted in typical fatigue-related accidents. Those having retired from driving had a more advanced (subjective) disease severity, higher age, more frequently female gender, an increased ESS score, and a longer disease duration. The study revealed SOS and daytime sleepiness as critical factors for traffic safety in addition to motor disabilities of PD patients. The results suggest that real sleep attacks without any prior sleepiness are rare. However, our data underline the importance of mobility for patients and the need for further studies addressing the ability to drive in PD. Copyright 2005 Movement Disorder Society.

Voluntary wheel-running attenuates insulin and weight gain and affects anxiety-like behaviors in C57BL6/J mice exposed to a high-fat diet.

PubMed

Hicks, Jasmin A; Hatzidis, Aikaterini; Arruda, Nicole L; Gelineau, Rachel R; De Pina, Isabella Monteiro; Adams, Kenneth W; Seggio, Joseph A

2016-09-01

It is widely accepted that lifestyle plays a crucial role on the quality of life in individuals, particularly in western societies where poor diet is correlated to alterations in behavior and the increased possibility of developing type-2 diabetes. While exercising is known to produce improvements to overall health, there is conflicting evidence on how much of an effect exercise has staving off the development of type-2 diabetes or counteracting the effects of diet on anxiety. Thus, this study investigated the effects of voluntary wheel-running access on the progression of diabetes-like symptoms and open field and light-dark box behaviors in C57BL/6J mice fed a high-fat diet. C57BL/6J mice were placed into either running-wheel cages or cages without a running-wheel, given either regular chow or a high-fat diet, and their body mass, food consumption, glucose tolerance, insulin and c-peptide levels were measured. Mice were also exposed to the open field and light-dark box tests for anxiety-like behaviors. Access to a running-wheel partially attenuated the obesity and hyperinsulinemia associated with high-fat diet consumption in these mice, but did not affect glucose tolerance or c-peptide levels. Wheel-running strongly increased anxiety-like and decreased explorative-like behaviors in the open field and light-dark box, while high-fat diet consumption produced smaller increases in anxiety. These results suggest that voluntary wheel-running can assuage some, but not all, of the physiological problems associated with high-fat diet consumption, and can modify anxiety-like behaviors regardless of diet consumed. Copyright © 2016 Elsevier B.V. All rights reserved.

49 CFR 213.345 - Vehicle/track system qualification.

Code of Federal Regulations, 2013 CFR

2013-10-01

... in accordance with the requirements of this paragraph (c). (1) Simulations or measurement of wheel/rail forces. For vehicle types intended to operate at track Class 6 speeds, simulations or measurement... exceed the wheel/rail force safety limits specified in § 213.333. Simulations, if conducted, shall be in...

49 CFR 213.345 - Vehicle/track system qualification.

Code of Federal Regulations, 2014 CFR

2014-10-01

... in accordance with the requirements of this paragraph (c). (1) Simulations or measurement of wheel/rail forces. For vehicle types intended to operate at track Class 6 speeds, simulations or measurement... exceed the wheel/rail force safety limits specified in § 213.333. Simulations, if conducted, shall be in...

Automatic control of a mobile Viking lander on the surface of Mars

NASA Technical Reports Server (NTRS)

Moore, J.; Scofield, W.; Tobey, W.

1976-01-01

A mobile lander system is being considered for use in a possible follow-on mission to the Viking '75 landings on Mars. A mobile Viking lander, which could be launched as early as the 1979 opportunity, would be capable of traversing 100 m to 1 km per day on a commanded heading while sensing hazards and performing avoidance maneuvers. The degree of autonomous control, and consequently the daily traverse range, is still under study. The mobility concept requires the addition of: (1) track-laying or wheel units in place of the Viking Lander footpads, (2) a set of hazard and navigation sensors, and (3) a mobility control computer capability. The technology required to develop these three subsystems is available today. The principal objective of current design studies, as described in this paper, is to define a mobile lander system that will demonstrate high reliability and fail-safe hazard avoidance while achieving range- and terrain-handling capabilities which satisfy the Mars exploration science requirements.

Acute Restraint Stress Alters Wheel-Running Behavior Immediately Following Stress and up to 20 Hours Later in House Mice.

PubMed

Malisch, Jessica L; deWolski, Karen; Meek, Thomas H; Acosta, Wendy; Middleton, Kevin M; Crino, Ondi L; Garland, Theodore

In vertebrates, acute stressors-although short in duration-can influence physiology and behavior over a longer time course, which might have important ramifications under natural conditions. In laboratory rats, for example, acute stress has been shown to increase anxiogenic behaviors for days after a stressor. In this study, we quantified voluntary wheel-running behavior for 22 h following a restraint stress and glucocorticoid levels 24 h postrestraint. We utilized mice from four replicate lines that have been selectively bred for high voluntary wheel-running activity (HR mice) for 60 generations and their nonselected control (C) lines to examine potential interactions between exercise propensity and sensitivity to stress. Following 6 d of wheel access on a 12L∶12D photo cycle (0700-1900 hours, as during the routine selective breeding protocol), 80 mice were physically restrained for 40 min, beginning at 1400 hours, while another 80 were left undisturbed. Relative to unrestrained mice, wheel running increased for both HR and C mice during the first hour postrestraint (P < 0.0001) but did not differ 2 or 3 h postrestraint. Wheel running was also examined at four distinct phases of the photoperiod. Running in the period of 1600-1840 hours was unaffected by restraint stress and did not differ statistically between HR and C mice. During the period of peak wheel running (1920-0140 hours), restrained mice tended to run fewer revolutions (-11%; two-tailed P = 0.0733), while HR mice ran 473% more than C (P = 0.0008), with no restraint × line type interaction. Wheel running declined for all mice in the latter part of the scotophase (0140-0600 hours), restraint had no statistical effect on wheel running, but HR again ran more than C (+467%; P = 0.0122). Finally, during the start of the photophase (0720-1200 hours), restraint increased running by an average of 53% (P = 0.0443) in both line types, but HR and C mice did not differ statistically. Mice from HR lines had statistically higher plasma corticosterone concentrations than C mice, with no statistical effect of restraint and no interaction between line type and restraint. Overall, these results indicate that acute stress can affect locomotor activity (or activity patterns) for many hours, with the most prominent effect being an increase in activity during a period of typical inactivity at the start of the photophase, 15-20 h poststressor.

Localization of a mobile laser scanner via dimensional reduction

NASA Astrophysics Data System (ADS)

Lehtola, Ville V.; Virtanen, Juho-Pekka; Vaaja, Matti T.; Hyyppä, Hannu; Nüchter, Andreas

2016-11-01

We extend the concept of intrinsic localization from a theoretical one-dimensional (1D) solution onto a 2D manifold that is embedded in a 3D space, and then recover the full six degrees of freedom for a mobile laser scanner with a simultaneous localization and mapping algorithm (SLAM). By intrinsic localization, we mean that no reference coordinate system, such as global navigation satellite system (GNSS), nor inertial measurement unit (IMU) are used. Experiments are conducted with a 2D laser scanner mounted on a rolling prototype platform, VILMA. The concept offers potential in being extendable to other wheeled platforms.

An adaptive actuator failure compensation scheme for two linked 2WD mobile robots

NASA Astrophysics Data System (ADS)

Ma, Yajie; Al-Dujaili, Ayad; Cocquempot, Vincent; El Badaoui El Najjar, Maan

2017-01-01

This paper develops a new adaptive compensation control scheme for two linked mobile robots with actuator failurs. A configuration with two linked two-wheel drive (2WD) mobile robots is proposed, and the modelling of its kinematics and dynamics are given. An adaptive failure compensation scheme is developed to compensate actuator failures, consisting of a kinematic controller and a multi-design integration based dynamic controller. The kinematic controller is a virtual one, and based on which, multiple adaptive dynamic control signals are designed which covers all possible failure cases. By combing these dynamic control signals, the dynamic controller is designed, which ensures system stability and asymptotic tracking properties. Simulation results verify the effectiveness of the proposed adaptive failure compensation scheme.

A satellite orbital testbed for SATCOM using mobile robots

NASA Astrophysics Data System (ADS)

Shen, Dan; Lu, Wenjie; Wang, Zhonghai; Jia, Bin; Wang, Gang; Wang, Tao; Chen, Genshe; Blasch, Erik; Pham, Khanh

2016-05-01

This paper develops and evaluates a satellite orbital testbed (SOT) for satellite communications (SATCOM). SOT can emulate the 3D satellite orbit using the omni-wheeled robots and a robotic arm. The 3D motion of satellite is partitioned into the movements in the equatorial plane and the up-down motions in the vertical plane. The former actions are emulated by omni-wheeled robots while the up-down motions are performed by a stepped-motor-controlled-ball along a rod (robotic arm), which is attached to the robot. The emulated satellite positions will go to the measure model, whose results will be used to perform multiple space object tracking. Then the tracking results will go to the maneuver detection and collision alert. The satellite maneuver commands will be translated to robots commands and robotic arm commands. In SATCOM, the effects of jamming depend on the range and angles of the positions of satellite transponder relative to the jamming satellite. We extend the SOT to include USRP transceivers. In the extended SOT, the relative ranges and angles are implemented using omni-wheeled robots and robotic arms.

Reduction of the shimmy tendency of tail and nose-wheel landing gears by installation of specially designed tires

NASA Technical Reports Server (NTRS)

Schrode, H

1955-01-01

Shimmy of tail and nose wheels may be eliminated by installation of dampers and use of large trail; however, this produces construction and operational disadvantages. It is more favorable to employ, instead of the customary tail-wheel tires, tires with lesser shimmy tendency. A description of the best possible form for these tires follows: furthermore, a few general concepts regarding the effects of the condition of the tire, of the type of rolling motion, and of the landing, are discussed.

International Assessment of Unmanned Ground Vehicles

DTIC Science & Technology

2008-02-01

research relevant to ground robotics include • Multi-sensor data fusion • Stereovision • Dedicated robots, including legged robots, tracked robots...Technology Laboratory has developed several mobile robots with leg - ged, wheeled, rolling, rowing, and hybrid locomotion. Areas of particular emphasis...117 UK Department of Trade and Industry ( DTI ) Global Watch Mission. November 2006. Mechatronics in Russia. 118 CRDI Web Site: http

Recent Acquisition Reform Through Technology and Workforce Improvements

DTIC Science & Technology

2016-09-01

HMMWV High Mobility Multipurpose Wheeled Vehicle IED Improvised Explosive Device IRAD Independent Research And Development JCIDS Joint...their specific field within the acquisition community (Eide & Allen, 2012). In 1993, the Government Performance and Results Act (GPRA) was enacted...need arises as the nation’s “adversaries are modernizing at a significant rate, and they are responding rapidly to our development programs and fielded

Virtual Reality and Computer-Enhanced Training Applied to Wheeled Mobility: An Overview of Work in Pittsburgh

ERIC Educational Resources Information Center

Cooper, Rory A.; Ding, Dan; Simpson, Richard; Fitzgerald, Shirley G.; Spaeth, Donald M.; Guo, Songfeng; Koontz, Alicia M.; Cooper, Rosemarie; Kim, Jongbae; Boninger, Michael L.

2005-01-01

Some aspects of assistive technology can be enhanced by the application of virtual reality. Although virtual simulation offers a range of new possibilities, learning to navigate in a virtual environment is not equivalent to learning to navigate in the real world. Therefore, virtual reality simulation is advocated as a useful preparation for…

Guidelines for Evaluating the Thermal Environment of Enclosed Spaces

DTIC Science & Technology

2009-09-01

space. Three studies of concrete tanks and metal containers, the High Mobility Multipurpose Wheeled Vehicle; and the Bradley Fighting Vehicle, are...24 13 The initial CST-WMD training site was a concrete casting site. The teams practiced entry and evacuation...Environmental Medicine (USARIEM) studies. Examples are presented from three case studies: one that involved monitoring large concrete septic tanks

Marine Corps Budgetary Reprogramming Effectiveness

DTIC Science & Technology

2015-03-01

infrastructure (Appropriations Act of Congress, 2008). The environmental restoration is a transfer account controlled by the DOD. Usually in the case of...at an average just over 11 percent and the Marine Corps encircle the backend of the DOD portion of reprogramming with the Marine Corps reprogramming...blue force tracker (BFT), radio systems, high mobility multipurpose wheeled vehicle (HMMWV), medium tactical vehicle replacement (MTVR), and

Laser beam methane detector

NASA Technical Reports Server (NTRS)

Hinkley, E. D., Jr.

1981-01-01

Instrument uses infrared absorption to determine methane concentration in liquid natural gas vapor. Two sensors measure intensity of 3.39 mm laser beam after it passes through gas; absorption is proportional to concentration of methane. Instrument is used in modeling spread of LNG clouds and as leak detector on LNG carriers and installations. Unit includes wheels for mobility and is both vertically and horizontally operable.

Using Motion Planning to Determine the Existence of an Accessible Route in a CAD Environment

ERIC Educational Resources Information Center

Pan, Xiaoshan; Han, Charles S.; Law, Kincho H.

2010-01-01

We describe an algorithm based on motion-planning techniques to determine the existence of an accessible route through a facility for a wheeled mobility device. The algorithm is based on LaValle's work on rapidly exploring random trees and is enhanced to take into consideration the particularities of the accessible route domain. Specifically, the…

Brownian movement and microscopic irreversibility

NASA Astrophysics Data System (ADS)

Gordon, L. G. M.

1981-02-01

An extension of the hypothetical experiment of Szilard, which involved the action of a one-molecule gas in an isolated isothermal system, is developed to illustrate how irreversibility may arise out of Brownian motion. As this development requires a consideration of nonmolecular components such as wheels and pistons, the thought-experiment is remodeled in molecular terms and appears to function as a perpetuum mobile.

"When I saw walking I just kind of took it as wheeling": interpretations of mobility-related items in generic, preference-based health state instruments in the context of spinal cord injury.

PubMed

Michel, Yvonne Anne; Engel, Lidia; Rand-Hendriksen, Kim; Augestad, Liv Ariane; Whitehurst, David Gt

2016-11-28

In health economic analyses, health states are typically valued using instruments with few items per dimension. Due to the generic (and often reductionist) nature of such instruments, certain groups of respondents may experience challenges in describing their health state. This study is concerned with generic, preference-based health state instruments that provide information for decisions about the allocation of resources in health care. Unlike physical measurement instruments, preference-based health state instruments provide health state values that are dependent on how respondents interpret the items. This study investigates how individuals with spinal cord injury (SCI) interpret mobility-related items contained within six preference-based health state instruments. Secondary analysis of focus group transcripts originally collected in Vancouver, Canada, explored individuals' perceptions and interpretations of mobility-related items contained within the 15D, Assessment of Quality of Life 8-dimension (AQoL-8D), EQ-5D-5L, Health Utilities Index (HUI), Quality of Well-Being Scale Self-Administered (QWB-SA), and the 36-item Short Form health survey version 2 (SF-36v2). Ritchie and Spencer's 'Framework Approach' was used to perform thematic analysis that focused on participants' comments concerning the mobility-related items only. Fifteen individuals participated in three focus groups (five per focus group). Four themes emerged: wording of mobility (e.g., 'getting around' vs 'walking'), reference to aids and appliances, lack of suitable response options, and reframing of items (e.g., replacing 'walking' with 'wheeling'). These themes reflected item features that respondents perceived as relevant in enabling them to describe their mobility, and response strategies that respondents could use when faced with inaccessible items. Investigating perceptions to mobility-related items within the context of SCI highlights substantial variation in item interpretation across six preference-based health state instruments. Studying respondents' interpretations of items can help to understand discrepancies in the health state descriptions and values obtained from different instruments. This line of research warrants closer attention in the health economics and quality of life literature.

Robust dead reckoning system for mobile robots based on particle filter and raw range scan.

PubMed

Duan, Zhuohua; Cai, Zixing; Min, Huaqing

2014-09-04

Robust dead reckoning is a complicated problem for wheeled mobile robots (WMRs), where the robots are faulty, such as the sticking of sensors or the slippage of wheels, for the discrete fault models and the continuous states have to be estimated simultaneously to reach a reliable fault diagnosis and accurate dead reckoning. Particle filters are one of the most promising approaches to handle hybrid system estimation problems, and they have also been widely used in many WMRs applications, such as pose tracking, SLAM, video tracking, fault identification, etc. In this paper, the readings of a laser range finder, which may be also interfered with by noises, are used to reach accurate dead reckoning. The main contribution is that a systematic method to implement fault diagnosis and dead reckoning in a particle filter framework concurrently is proposed. Firstly, the perception model of a laser range finder is given, where the raw scan may be faulty. Secondly, the kinematics of the normal model and different fault models for WMRs are given. Thirdly, the particle filter for fault diagnosis and dead reckoning is discussed. At last, experiments and analyses are reported to show the accuracy and efficiency of the presented method.

Robust Dead Reckoning System for Mobile Robots Based on Particle Filter and Raw Range Scan

PubMed Central

Duan, Zhuohua; Cai, Zixing; Min, Huaqing

2014-01-01

Robust dead reckoning is a complicated problem for wheeled mobile robots (WMRs), where the robots are faulty, such as the sticking of sensors or the slippage of wheels, for the discrete fault models and the continuous states have to be estimated simultaneously to reach a reliable fault diagnosis and accurate dead reckoning. Particle filters are one of the most promising approaches to handle hybrid system estimation problems, and they have also been widely used in many WMRs applications, such as pose tracking, SLAM, video tracking, fault identification, etc. In this paper, the readings of a laser range finder, which may be also interfered with by noises, are used to reach accurate dead reckoning. The main contribution is that a systematic method to implement fault diagnosis and dead reckoning in a particle filter framework concurrently is proposed. Firstly, the perception model of a laser range finder is given, where the raw scan may be faulty. Secondly, the kinematics of the normal model and different fault models for WMRs are given. Thirdly, the particle filter for fault diagnosis and dead reckoning is discussed. At last, experiments and analyses are reported to show the accuracy and efficiency of the presented method. PMID:25192318

A new family of low cost momentum/reaction wheels

NASA Astrophysics Data System (ADS)

Bialke, Bill

In order to satisfy the tight budgets and stringent power requirements of small and medium sized satellites, a new series of momentum/reaction wheels has been developed by ITHACO, Inc. The T-WHEEL integrates state-of-the-art ball bearing technology with flight-proven materials and conventional fabrication techniques to produce a reliable and manufacturable wheel assembly. Maximum performance is attained by using an optimized ball bearing suspension system and an ironless armature brushless dc motor for low power dissipation and minimum weight. In addition to summaries of the tradeoff studies performed, the results of the development effort include the application of a low vapor pressure synthetic hydrocarbon lubricant in the ball bearing suspension system, and performance data from the ironless armature brushless dc motor and driver. The original 4 N-m-s version (Type A) has been enlarged to increase the momentum storage capacity to 19.5 N-m-s (Type B), using the same suspension system and design baseline. A 68 N-m-s version is currently under development to broaden the product family.

Analysis and design of a capsule landing system and surface vehicle control system for Mars exploration

NASA Technical Reports Server (NTRS)

Frederick, D. K.; Lashmet, P. K.; Sandor, G. N.; Shen, C. N.; Smith, E. V.; Yerazunis, S. W.

1973-01-01

Problems related to the design and control of a mobile planetary vehicle to implement a systematic plan for the exploration of Mars are reported. Problem areas include: vehicle configuration, control, dynamics, systems and propulsion; systems analysis, terrain modeling and path selection; and chemical analysis of specimens. These tasks are summarized: vehicle model design, mathematical model of vehicle dynamics, experimental vehicle dynamics, obstacle negotiation, electrochemical controls, remote control, collapsibility and deployment, construction of a wheel tester, wheel analysis, payload design, system design optimization, effect of design assumptions, accessory optimal design, on-board computer subsystem, laser range measurement, discrete obstacle detection, obstacle detection systems, terrain modeling, path selection system simulation and evaluation, gas chromatograph/mass spectrometer system concepts, and chromatograph model evaluation and improvement.

Free Access to Running Wheels Abolishes Hyperphagia in Human Growth Hormone Transgenic Rats

PubMed Central

KOMATSUDA, Mugiko; YAMANOUCHI, Keitaro; MATSUWAKI, Takashi; NISHIHARA, Masugi

2014-01-01

ABSTRACT Obesity is a major health problem, and increased food intake and decreased physical activity are considered as two major factors causing obesity. Previous studies show that voluntary exercise in a running wheel decreases not only body weight but also food intake of rats. We previously produced human growth hormone transgenic (TG) rats, which are characterized by severe hyperphagia and obesity. To gain more insight into the effects on physical activity to food consumption and obesity, we examined whether voluntary running wheel exercise causes inhibition of hyperphagia and alteration of body composition in TG rats. Free access to running wheels completely abolished hyperphagia in TG rats, and this effect persisted for many weeks as far as the running wheel is accessible. Unexpectedly, though the running distances of TG rats were significantly less than those of wild type rats, it was sufficient to normalize their food consumption. This raises the possibility that rearing environment, which enables them to access to a running wheel freely, rather than the amounts of physical exercises is more important for the maintenance of proper food intake. PMID:24717416

Free access to running wheels abolishes hyperphagia in human growth hormone transgenic rats.

PubMed

Komatsuda, Mugiko; Yamanouchi, Keitaro; Matsuwaki, Takashi; Nishihara, Masugi

2014-07-01

Obesity is a major health problem, and increased food intake and decreased physical activity are considered as two major factors causing obesity. Previous studies show that voluntary exercise in a running wheel decreases not only body weight but also food intake of rats. We previously produced human growth hormone transgenic (TG) rats, which are characterized by severe hyperphagia and obesity. To gain more insight into the effects on physical activity to food consumption and obesity, we examined whether voluntary running wheel exercise causes inhibition of hyperphagia and alteration of body composition in TG rats. Free access to running wheels completely abolished hyperphagia in TG rats, and this effect persisted for many weeks as far as the running wheel is accessible. Unexpectedly, though the running distances of TG rats were significantly less than those of wild type rats, it was sufficient to normalize their food consumption. This raises the possibility that rearing environment, which enables them to access to a running wheel freely, rather than the amounts of physical exercises is more important for the maintenance of proper food intake.

In Situ Resource Utilization For Mobility In Mars Exploration

NASA Astrophysics Data System (ADS)

Hartman, Leo

There has been considerable interest in the unmanned exploration of Mars for quite some time but the current generation of rovers can explore only a small portion of the total planetary surface. One approach to addressing this deficiency is to consider a rover that has greater range and that is cheaper so that it can be deployed in greater numbers. The option explored in this paper uses the wind to propel a rover platform, trading off precise navigation for greater range. The capabilities of such a rover lie between the global perspective of orbiting satellites and the detailed local analysis of current-generation rovers. In particular, the design includes two inflatable wheels with an unspun payload platform suspended between then. Slightly deflating one of the wheels enables steering away from the direction of the wind and sufficiently deflating both wheels will allow the rover to stop. Current activities revolve around the development of a prototype with a wheel cross-sectional area that is scaled by 1/100 to enable terrestrial trials to provide meaningful insight into the performance and behavior of a full-sized rover on Mars. The paper will discuss the design and its capabilities in more detail as well as current efforts to build a prototype suitable for deployment at a Mars analogue site such as Devon Island in the Canadian arctic.

A Mobile Sensor Network System for Monitoring of Unfriendly Environments.

PubMed

Song, Guangming; Zhou, Yaoxin; Ding, Fei; Song, Aiguo

2008-11-14

Observing microclimate changes is one of the most popular applications of wireless sensor networks. However, some target environments are often too dangerous or inaccessible to humans or large robots and there are many challenges for deploying and maintaining wireless sensor networks in those unfriendly environments. This paper presents a mobile sensor network system for solving this problem. The system architecture, the mobile node design, the basic behaviors and advanced network capabilities have been investigated respectively. A wheel-based robotic node architecture is proposed here that can add controlled mobility to wireless sensor networks. A testbed including some prototype nodes has also been created for validating the basic functions of the proposed mobile sensor network system. Motion performance tests have been done to get the positioning errors and power consumption model of the mobile nodes. Results of the autonomous deployment experiment show that the mobile nodes can be distributed evenly into the previously unknown environments. It provides powerful support for network deployment and maintenance and can ensure that the sensor network will work properly in unfriendly environments.

Mathematical model of rolling an elastic wheel over deformable support base

NASA Astrophysics Data System (ADS)

Volskaia, V. N.; Zhileykin, M. M.; Zakharov, A. Y.

2018-02-01

One of the main direction of economic growth in Russia remains to be a speedy development of north and northeast regions that are the constituents of the 60 percent of the country territory. The further development of these territories requires new methods and technologies for solving transport and technological problems when off-road transportation of cargoes and people is conducting. One of the fundamental methods of patency prediction is imitation modeling of wheeled vehicles movement in different operating conditions. Both deformable properties of tires and physical and mechanical properties of the ground: normal tire deflection and gauge depth; variation of contact patch area depending on the load and pressure of air in the tire; existence of hysteresis losses in the tire material which are influencing on the rolling resistance due to friction processes between tire and ground in the contact patch; existence of the tangential reaction from the ground by entire contact area influence on the tractive patency. Nowadays there are two main trends in theoretical research of interaction wheeled propulsion device with ground: analytical method involving mathematical description of explored process and finite element method based on computational modeling. Mathematical models of interaction tire with the ground are used both in processes of interaction individual wheeled propulsion device with ground and researches of mobile vehicle dynamical models operated in specific road and climate conditions. One of the most significant imperfection of these models is the description of interaction wheel with flat deformable support base whereas profile of real support base surface has essential height of unevenness which is commensurate with radius of the wheel. The description of processes taking place in the ground under influence of the wheeled propulsion device using the finite element method is relatively new but most applicable lately. The application of this method allows to provide the most accurate description of the interaction process of a wheeled propulsion devices and the ground, also this method allows to define tension in the ground, deformation of the ground and the tire and ground’s compression. However, the high laboriousness of computations is essential shortcoming of that method therefore it’s hard to use these models as part of the general motion model of multi-axis wheeled vehicles. The purpose of this research is the elaboration of mathematical model of elastic wheel rolling over deformable rough support base taking into account the contact patch deformation. The mathematical model of rectilinear rolling an elastic wheel over rough deformable support base, taking into account variation of contact patch area and variation in the direction of the radial and tangential reactions also load bearing capacity of the ground, is developed. The efficiency of developed mathematical model of rectilinear rolling an elastic wheel over rough deformable support base is proved by the simulation methods.

Wheelset curving guidance using H∞ control

NASA Astrophysics Data System (ADS)

Qazizadeh, Alireza; Stichel, Sebastian; Feyzmahdavian, Hamid Reza

2018-03-01

This study shows how to design an active suspension system for guidance of a rail vehicle wheelset in curve. The main focus of the study is on designing the controller and afterwards studying its effect on the wheel wear behaviour. The controller is designed based on the closed-loop transfer function shaping method and ? control strategy. The study discusses designing of the controller for both nominal and uncertain plants and considers both stability and performance. The designed controllers in Simulink are then applied to the vehicle model in Simpack to study the wheel wear behaviour in curve. The vehicle type selected for this study is a two-axle rail vehicle. This is because this type of vehicle is known to have very poor curving performance and high wheel wear. On the other hand, the relative simpler structure of this type of vehicle compared to bogie vehicles make it a more economic choice. Hence, equipping this type of vehicle with the active wheelset steering is believed to show high enough benefit to cost ratio to remain attractive to rail vehicle manufacturers and operators.

Development and evaluation of a new taxonomy of mobility-related assistive technology devices.

PubMed

Shoemaker, Laura L; Lenker, James A; Fuhrer, Marcus J; Jutai, Jeffrey W; Demers, Louise; DeRuyter, Frank

2010-10-01

This article reports on the development of a new taxonomy for mobility-related assistive technology devices. A prototype taxonomy was created based on the extant literature. Five mobility device experts were engaged in a modified Delphi process to evaluate and refine the taxonomy. Multiple iterations of expert feedback and revision yielded consensual agreement on the structure and terminology of a new mobility device taxonomy. The taxonomy uses a hierarchical framework to classify ambulation aids and wheeled mobility devices, including their key features that impact mobility. Five attributes of the new taxonomy differentiate it from previous mobility-related device classifications: (1) hierarchical structure, (2) primary device categories are grouped based on their intended mobility impact, (3) comprehensive inclusion of technical features, (4) a capacity to assimilate reimbursement codes, and (5) availability of a detailed glossary. The taxonomy is intended to support assistive technology outcomes research. The taxonomy will enable researchers to capture mobility-related assistive technology device interventions with precision and provide a common terminology that will allow comparisons among studies. The prominence of technical features within the new taxonomy will hopefully promote research that helps clinicians predict how devices will perform, thus aiding clinical decision making and supporting funding recommendations.

The role of the built environment and assistive devices for outdoor mobility in later life.

PubMed

Clarke, Philippa J

2014-11-01

Despite theoretical advances in our conceptualization of disability, the "environment" remains a largely unspecified term in disablement models. The purpose of this research is to draw upon on a unique state-of-the-art nationally representative data set with innovative measures that provide the opportunity to tease apart and specify the role of different environmental factors in the disablement process. Using multinomial logistic regression with data from the first round of the recently launched National Health and Aging Trends Study (N = 6,578 community-dwelling Americans age 65+), this paper examines the role of the built environment (e.g., stairs or ramps leading up to the home) and mobility devices on reported difficulty going outside by oneself. Almost three quarters of community-dwelling older Americans live in a residence that has stairs at the entrance. Older adults who use a walker to help them get around are adversely affected by stairs at the entrance to their home, effectively doubling the odds of reporting difficulty going outside independently. Roughly 10% of community-dwelling older Americans live in a residence with a ramp at the entryway, which reduces the odds of outdoor mobility difficulty threefold among those using wheeled mobility devices. However, ramps at the entryway are associated with a higher likelihood of reporting difficulty going outdoors among those who do not use any type of mobility device. A better understanding of the complexities of the environment in the disablement process is critical for the planning and development of age-friendly environments allowing older adults to age in place. © The Author 2014. Published by Oxford University Press on behalf of The Gerontological Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

More screen operation than calling: the results of observing cyclists' behaviour while using mobile phones.

PubMed

de Waard, Dick; Westerhuis, Frank; Lewis-Evans, Ben

2015-03-01

Operating a mobile telephone while riding a bicycle is fairly common practice in the Netherlands, yet it is unknown if this use is stable or increasing. As such, whether the prevalence of mobile phone use while cycling has changed over the past five years was studied via on-road observation. In addition the impact of mobile phone use on lateral position, i.e. distance from the front wheel to the curb, was also examined to see if it compared to the results seen in previous experimental studies. Bicyclists were observed at six different locations and their behaviour was scored. It was found that compared to five years ago the use of mobile phones while cycling has changed, not in frequency, but in how cyclists were operating their phones. As found in 2008, three percent of the bicyclists were observed to be operating a phone, but a shift from calling (0.7% of cyclists observed) to operating (typing, texting, 2.3% of cyclists) was found. In 2008 nearly the complete opposite usage was observed: 2.2% of the cyclists were calling and 0.6% was texting. Another finding was that effects on lateral position were similar to those seen in experimental studies in that cyclists using a phone maintained a cycling position which was further away from the curb. It was also found that when at an intersection, cyclist's operating their phone made less head movements to the right than cyclists who were just cycling. This shift from calling to screen operation, when combined with the finding related to reduced head movements at intersections, is worrying and potentially dangerous. Copyright © 2015 Elsevier Ltd. All rights reserved.

Technological advances in powered wheelchairs.

PubMed

Edlich, Richard F; Nelson, Kenneth P; Foley, Marni L; Buschbacher, Ralph M; Long, William B; Ma, Eva K

2004-01-01

During the last 40 years, there have been revolutionary advances in power wheelchairs. These unique wheelchair systems, designed for the physically immobile patient, have become extremely diversified, allowing the user to achieve different positions, including tilt, recline, and, more recently, passive standing. Because of this wide diversity of powered wheelchair products, there is a growing realization of the need for certification of wheeled mobility suppliers. Legislation in Tennessee (Consumer Protection Act for Wheeled Mobility) passed in 2003 will ensure that wheeled mobility suppliers must have Assistive Technology Supplier certification and maintain their continuing education credits when fitting individuals in wheelchairs for long-term use. Fifteen other legislative efforts are currently underway in general assemblies throughout the US. Manufacturers, dealers, hospitals, and legislators are working toward the ultimate goal of passing federal legislation delineating the certification process of wheeled mobility suppliers. The most recent advance in the design of powered wheelchairs is the development of passive standing positions. The beneficial effects of passive standing have been documented by comprehensive scientific studies. These benefits include reduction of seating pressure, decreased bone demineralization, increased bladder pressure, enhanced orthostatic circulatory regulation, reduction in muscular tone, decrease in upper extremity muscle stress, and enhanced functional status in general. In February 2003, Permobil, Inc., introduced the powered Permobil Chairman 2K Stander wheelchair, which can tilt, recline, and stand. Other companies are now manufacturing powered wheelchairs that can achieve a passive standing position. These wheelchairs include the Chief SR Powerchair, VERTRAN, and LifeStand Compact. Another new addition to the wheelchair industry is the iBOT, which can elevate the user to reach cupboards and climb stairs but has no passive standing capabilities. In addition, the physically immobile patient must be seated on an ERGODYNAMIC Seating System 2000, which is inflated by the alternating pressure compressor 8080. This seating system has a deep center seam between the two ischial-support chambers, which provides a recess for the coccyx. The pre-ischial crossbar compartment inflates during each cycle to prevent the pelvis from slipping forward. It is essential that the physician of the immobile patient order two ERGODYNAMIC Seating Systems 2000 because the patient must have an additional seating system in the case one leaks. Moreover, two compressors are necessary because each compressor must be serviced after 2500 hours of use. For the protection of the consumer, these pressure relief systems must be supplied and serviced by a Certified Rehabilitation Technology Supplier such as Wheelchair Works Inc. Despite the indisputable scientific evidence of the medical benefits of passive standing for the immobile user, few individuals have access to these revolutionary wheelchairs. Consequently, it is mandatory that the medical community, headed by specialists in physical and occupational therapy as well as rehabilitation medicine, CRTS, and manufacturers collaborate in a national education campaign to convince Medicare/Medicaid and all commercial insurance companies to approve immediately these assisted technologies. This program is essential so that the physically immobilized patient can achieve the undisputed physical benefits of passive standing.

Aspects of manual wheelchair configuration affecting mobility: a review.

PubMed

Medola, Fausto Orsi; Elui, Valeria Meirelles Carril; Santana, Carla da Silva; Fortulan, Carlos Alberto

2014-02-01

Many aspects relating to equipment configuration affect users' actions in a manual wheelchair, determining the overall mobility performance. Since the equipment components and configuration determine both stability and mobility efficiency, configuring the wheelchair with the most appropriate set-up for individual users' needs is a difficult task. Several studies have shown the importance of seat/backrest assembly and the relative position of the rear wheels to the user in terms of the kinetics and kinematics of manual propulsion. More recently, new studies have brought to light evidence on the inertial properties of different wheelchair configurations. Further new studies have highlighted the handrim as a key component of wheelchair assembly, since it is the interface through which the user drives the chair. In light of the new evidence on wheelchair mechanics and propulsion kinetics and kinematics, this article presents a review of the most important aspects of wheelchair configuration that affect the users' actions and mobility.

Aspects of Manual Wheelchair Configuration Affecting Mobility: A Review

PubMed Central

Medola, Fausto Orsi; Elui, Valeria Meirelles Carril; Santana, Carla da Silva; Fortulan, Carlos Alberto

2014-01-01

Many aspects relating to equipment configuration affect users’ actions in a manual wheelchair, determining the overall mobility performance. Since the equipment components and configuration determine both stability and mobility efficiency, configuring the wheelchair with the most appropriate set-up for individual users’ needs is a difficult task. Several studies have shown the importance of seat/backrest assembly and the relative position of the rear wheels to the user in terms of the kinetics and kinematics of manual propulsion. More recently, new studies have brought to light evidence on the inertial properties of different wheelchair configurations. Further new studies have highlighted the handrim as a key component of wheelchair assembly, since it is the interface through which the user drives the chair. In light of the new evidence on wheelchair mechanics and propulsion kinetics and kinematics, this article presents a review of the most important aspects of wheelchair configuration that affect the users’ actions and mobility. PMID:24648656

Intelligent mobility for robotic vehicles in the army after next

NASA Astrophysics Data System (ADS)

Gerhart, Grant R.; Goetz, Richard C.; Gorsich, David J.

1999-07-01

The TARDEC Intelligent Mobility program addresses several essential technologies necessary to support the army after next (AAN) concept. Ground forces in the AAN time frame will deploy robotic unmanned ground vehicles (UGVs) in high-risk missions to avoid exposing soldiers to both friendly and unfriendly fire. Prospective robotic systems will include RSTA/scout vehicles, combat engineering/mine clearing vehicles, indirect fire artillery and missile launch platforms. The AAN concept requires high on-road and off-road mobility, survivability, transportability/deployability and low logistics burden. TARDEC is developing a robotic vehicle systems integration laboratory (SIL) to evaluate technologies and their integration into future UGV systems. Example technologies include the following: in-hub electric drive, omni-directional wheel and steering configurations, off-road tires, adaptive tire inflation, articulated vehicles, active suspension, mine blast protection, detection avoidance and evasive maneuver. This paper will describe current developments in these areas relative to the TARDEC intelligent mobility program.

Experimental Procedure for Warm Spinning of Cast Aluminum Components.

PubMed

Roy, Matthew J; Maijer, Daan M

2017-02-01

High performance, cast aluminum automotive wheels are increasingly being incrementally formed via flow forming/metal spinning at elevated temperatures to improve material properties. With a wide array of processing parameters which can affect both the shape attained and resulting material properties, this type of processing is notoriously difficult to commission. A simplified, light-duty version of the process has been designed and implemented for full-size automotive wheels. The apparatus is intended to assist in understanding the deformation mechanisms and the material response to this type of processing. An experimental protocol has been developed to prepare for, and subsequently perform forming trials and is described for as-cast A356 wheel blanks. The thermal profile attained, along with instrumentation details are provided. Similitude with full-scale forming operations which impart significantly more deformation at faster rates is discussed.

Development of wall climbing robot

NASA Astrophysics Data System (ADS)

Kojima, Hisao; Toyama, Ryousei; Kobayashi, Kengo

1992-03-01

A configuration design is presented for a wall-climbing robot with high payload which is capable of moving on diversified surfaces of walls including the wall surface to ceilings in every direction. A developed quadruped wall climbing robot, NINJYA-1, is introduced. NINJYA-1 is composed of legs based on a 3D parallel link mechanism and a VM (Valve-regulated Multiple) sucker which will be able to suck even if there are grooves and a small difference in level. A wall climbing robot which supports rescue operation at a high building using a VM sucker is also introduced. Finally, a wall climbing robot named Disk Rover with a disk-type magnetic wheel is shown. The wheel shape is calculated by FEM. The disk-type magnetic wheel has a force three times more powerful than the one heretofore in use.

Experimental Procedure for Warm Spinning of Cast Aluminum Components

PubMed Central

Roy, Matthew J.; Maijer, Daan M.

2017-01-01

High performance, cast aluminum automotive wheels are increasingly being incrementally formed via flow forming/metal spinning at elevated temperatures to improve material properties. With a wide array of processing parameters which can affect both the shape attained and resulting material properties, this type of processing is notoriously difficult to commission. A simplified, light-duty version of the process has been designed and implemented for full-size automotive wheels. The apparatus is intended to assist in understanding the deformation mechanisms and the material response to this type of processing. An experimental protocol has been developed to prepare for, and subsequently perform forming trials and is described for as-cast A356 wheel blanks. The thermal profile attained, along with instrumentation details are provided. Similitude with full-scale forming operations which impart significantly more deformation at faster rates is discussed. PMID:28190063

Family needs of parents of children and youth with cerebral palsy.

PubMed

Palisano, R J; Almarsi, N; Chiarello, L A; Orlin, M N; Bagley, A; Maggs, J

2010-01-01

Understanding the needs of families of children and youth with cerebral palsy (CP) is important for family-centred services. The aims of this study were to identify: (1) differences in the number and types of family needs expressed by parents based on the age and gross motor function level of their children with CP; (2) the most frequent family needs; and (3) needs that differ on gross motor function level. A total of 501 parents (77.6% mothers) of children and youth with CP completed a modified version of a Family Needs Survey and a demographic questionnaire. Children's gross motor function level was classified using the Gross Motor Function Classification System. Total number of family needs differed based on gross motor function level (P < 0.001) but not age. Parents of children/youth who use wheeled mobility expressed the highest number of family needs, while parents of children/youth who walk without restrictions expressed the fewest needs. Family needs for Information (P= 0.001), Support (P= 0.001), Community Services (P < 0.001) and Finances (P < 0.001) differed based on children's gross motor function level. Over 50% of parents expressed family needs for information on current and future services, planning for the future, help in locating community activities and more personal time. Parents of children and youth who use wheeled mobility were more likely to express the need for help in paying for home modifications, equipment, services and locating sitters, respite care providers and community activities. The gross motor function of children/youth with CP has implications for collaboration with families to identify needs and co-ordinate services. Health professionals have a role to assist families with information needs and locating community services and leisure activities. Family needs for future planning suggest that health professionals should assist families to prepare for key periods in the lives of their children with CP.

Sustainable Rural Energy: Traditional Water Wheels in Padang (PWW) Indonesia

NASA Astrophysics Data System (ADS)

Ibrahim, Gusri Akhyar; Haron, Che Hassan Che; Azhari, Che Husna

2010-06-01

Renewable and sustainable energy is increasingly gaining interest in current research circles due to the debates on renewable energy resources. It is essential for scientists and researchers to search for solutions in renewable energy resources, with effective technologies, and low cost in operation and maintenance. Hydro resources can be considered a potential renewable energy resource. The traditional water wheel with simple construction coupled with a basic concept of technology can be utilised as a renewable and sustainable rural energy system. This paper discusses the case of the water wheel as a renewable energy system employed in Padang, Indonesia. The Padang water wheel is constructed from hardwood material with a diameter of 300 cm and width of 40 cm. It is built on a river using water flow to generate the movement of the wheel. The water wheel application in the area showed that it is suitable to be utilised to elevate and distribute water to rice fields located at a higher level than the water level of the river. The water wheel capacity is about 100-120 liters/min. It could continuously irrigate ±5 ha. of the rice fields. One of the advantages of this water wheel type is to function as a green technology concept promising no negative effect on the environment. The traditional water wheel has also a big economic impact on the rural economy, increasing the productivity of the rice fields. The people of Padang live in a water landscape encompassing the water wheel as an ubiquitous part of their lives, hence they relate to it and the technology of fabrication as well as the utilisation, making it an amenable and effective technology, finding relevance in the modern world.

Adding navigation, artificial audition and vital sign monitoring capabilities to a telepresence mobile robot for remote home care applications.

PubMed

Laniel, Sebastien; Letourneau, Dominic; Labbe, Mathieu; Grondin, Francois; Polgar, Janice; Michaud, Francois

2017-07-01

A telepresence mobile robot is a remote-controlled, wheeled device with wireless internet connectivity for bidirectional audio, video and data transmission. In health care, a telepresence robot could be used to have a clinician or a caregiver assist seniors in their homes without having to travel to these locations. Many mobile telepresence robotic platforms have recently been introduced on the market, bringing mobility to telecommunication and vital sign monitoring at reasonable costs. What is missing for making them effective remote telepresence systems for home care assistance are capabilities specifically needed to assist the remote operator in controlling the robot and perceiving the environment through the robot's sensors or, in other words, minimizing cognitive load and maximizing situation awareness. This paper describes our approach adding navigation, artificial audition and vital sign monitoring capabilities to a commercially available telepresence mobile robot. This requires the use of a robot control architecture to integrate the autonomous and teleoperation capabilities of the platform.

Terrain interaction with the quarter scale beam walker

NASA Technical Reports Server (NTRS)

Chun, Wendell H.; Price, S.; Spiessbach, A.

1990-01-01

Frame walkers are a class of mobile robots that are robust and capable mobility platforms. Variations of the frame walker robot are in commercial use today. Komatsu Ltd. of Japan developed the Remotely Controlled Underwater Surveyor (ReCUS) and Normed Shipyards of France developed the Marine Robot (RM3). Both applications of the frame walker concept satisfied robotic mobility requirements that could not be met by a wheeled or tracked design. One vehicle design concept that falls within this class of mobile robots is the walking beam. A one-quarter scale prototype of the walking beam was built by Martin Marietta to evaluate the potential merits of utilizing the vehicle as a planetary rover. The initial phase of prototype rover testing was structured to evaluate the mobility performance aspects of the vehicle. Performance parameters such as vehicle power, speed, and attitude control were evaluated as a function of the environment in which the prototype vehicle was tested. Subsequent testing phases will address the integrated performance of the vehicle and a local navigation system.

Terrain Interaction With The Quarter Scale Beam Walker

NASA Astrophysics Data System (ADS)

Chun, Wendell H.; Price, R. S.; Spiessbach, Andrew J.

1990-03-01

Frame walkers are a class of mobile robots that are robust and capable mobility platforms. Variations of the frame walker robot are in commercial use today. Komatsu Ltd. of Japan developed the Remotely Controlled Underwater Surveyor (ReCUS) and Normed Shipyards of France developed the Marine Robot (RM3). Both applications of the frame walker concept satisfied robotic mobility requirements that could not be met by a wheeled or tracked design. One vehicle design concept that falls within this class of mobile robots is the walking beam. A one-quarter scale prototype of the walking beam was built by Martin Marietta to evaluate the potential merits of utilizing the vehicle as a planetary rover. The initial phase of prototype rover testing was structured to evaluate the mobility performance aspects of the vehicle. Performance parameters such as vehicle power, speed, and attitude control were evaluated as a function of the environment in which the prototype vehicle was tested. Subsequent testing phases will address the integrated performance of the vehicle and a local navigation system.

Design and evaluation of Mina: a robotic orthosis for paraplegics.

PubMed

Neuhaus, Peter D; Noorden, Jerryll H; Craig, Travis J; Torres, Tecalote; Kirschbaum, Justin; Pratt, Jerry E

2011-01-01

Mobility options for persons suffering from paraplegia or paraparesis are limited to mainly wheeled devices. There are significant health, psychological, and social consequences related to being confined to a wheelchair. We present the Mina, a robotic orthosis for assisting mobility, which offers a legged mobility option for these persons. Mina is an overground robotic device that is worn on the back and around the legs to provide mobility assistance for people suffering from paraplegia or paraparesis. Mina uses compliant actuation to power the hip and knee joints. For paralyzed users, balance is provided with the assistance of forearm crutches. This paper presents the evaluation of Mina with two paraplegics (SCI ASIA-A). We confirmed that with a few hours of training and practice, Mina is currently able to provide paraplegics walking mobility at speeds of up to 0.20 m/s. We further confirmed that using Mina is not physically taxing and requires little cognitive effort, allowing the user to converse and maintain eye contact while walking. © 2011 IEEE

Mobile robot trajectory tracking using noisy RSS measurements: an RFID approach.

PubMed

Miah, M Suruz; Gueaieb, Wail

2014-03-01

Most RF beacons-based mobile robot navigation techniques rely on approximating line-of-sight (LOS) distances between the beacons and the robot. This is mostly performed using the robot's received signal strength (RSS) measurements from the beacons. However, accurate mapping between the RSS measurements and the LOS distance is almost impossible to achieve in reverberant environments. This paper presents a partially-observed feedback controller for a wheeled mobile robot where the feedback signal is in the form of noisy RSS measurements emitted from radio frequency identification (RFID) tags. The proposed controller requires neither an accurate mapping between the LOS distance and the RSS measurements, nor the linearization of the robot model. The controller performance is demonstrated through numerical simulations and real-time experiments. ©2013 Published by ISA. All rights reserved.

Mobility as an emergent property of biological organization: Insights from experimental evolution.

PubMed

Wallace, Ian J; Garland, Theodore

2016-05-06

Anthropologists accept that mobility is a critical dimension of human culture, one that links economy, technology, and social relations. Less often acknowledged is that mobility depends on complex and dynamic interactions between multiple levels of our biological organization, including anatomy, physiology, neurobiology, and genetics. Here, we describe a novel experimental approach to examining the biological foundations of mobility, using mice from a long-term artificial selection experiment for high levels of voluntary exercise on wheels. In this experiment, mice from selectively bred lines have evolved to run roughly three times as far per day as those from nonselected control lines. We consider three insights gleaned from this experiment as foundational principles for the study of mobility from the perspective of biological evolution. First, an evolutionary change in mobility will necessarily be associated with alterations in biological traits both directly and indirectly connected to mobility. Second, changing mobility will result in trade-offs and constraints among some of the affected traits. Third, multiple solutions exist to altering mobility, so that various combinations of adjustments to traits linked with mobility can achieve the same overall behavioral outcome. We suggest that anthropological knowledge of variation in human mobility might be improved by greater research attention to its biological dimensions. © 2016 Wiley Periodicals, Inc.

Development of a magnetically suspended momentum wheel

NASA Technical Reports Server (NTRS)

Hamilton, S. B.

1973-01-01

An engineering model of a magnetically suspended momentum wheel was designed, fabricated, and tested under laboratory conditions. The basic unit consisted of two magnet bearings, a sculptured aluminum rotor, brushless dc spin motor, and electronics. The magnet bearings, utilizing rare-earth cobltrat-samarium magnets were active radially and passive axially. The results of the program showed that momentum wheels with magnetic bearings are feasible and operable, and that magnetic bearings of this type are capable of being used for applications where high capacity, high stiffness, and low power consumption are required. The tests performed developed criteria for improved performance for future designs.

Alternate bearing design fabrication and test program, exhibit B

NASA Technical Reports Server (NTRS)

1978-01-01

A 50 ft-lb-sec (FPS) reaction wheel was modified with an ironless armature brushless dc motor and a magnetic bearing suspension. The purpose was to demonstrate the performance of an alternate bearing concept, i.e., a magnetic bearing suspension, which could be used in Skylab type CMG's to meet the attitude control requirements of long term space stations. A magnetic suspension was built, installed and tested in the 50 FPS reaction wheel. A secondary effort included the build and test of a compatible reaction wheel motor. Performance characteristics of both are presented and discussed.

2010 Combat Vehicles Conference

DTIC Science & Technology

2010-11-09

7 The Tactical Wheeled Vehicle Challenge… Performance ProtectionPayload Weight Mobility Transportability Cost / Benefit The fully burdened cost of...employment of robotic systems 10 Ground Combat Vehicle… Versatility – Configuration and employment options – Employed across full range of military...Synchronization 11-12 13-14 15-16 17-18 19-20 21-22 23-24 25-26 = Increment Point STOP STOP ~ 2034 Developing a Combat Vehicle Strategy… 11 “… robotics

Manual wheeled mobility--current and future developments from the human engineering research laboratories.

PubMed

Cooper, Rory A; Koontz, Alicia M; Ding, Dan; Kelleher, Annmarie; Rice, Ian; Cooper, Rosemarie

2010-01-01

Medical rehabilitation and assistive technology are immersed in a world transitioning to a basis in evidence-based practice. Fortunately, there is a growing body of knowledge related to manual wheelchair mobility to form a basis for clinical decision making. The results from research studies are useful for designing better wheelchairs, fitting and training people appropriately, contributing to evidence-based-medicine and guiding future research. This review describes some of the work related to manual wheelchairs that has and is being conducted within the University of Pittsburgh and the Human Engineering Research Laboratories of the United States Department of Veterans Affairs, and its application.

Value-based design for the elderly: An application in the field of mobility aids.

PubMed

Boerema, Simone T; van Velsen, Lex; Vollenbroek-Hutten, Miriam M R; Hermens, Hermie J

2017-01-01

In the aging society, the need for the elderly to remain mobile and independent is higher than ever. However, many aids supporting mobility often fail to target real needs and lack acceptance. The aim of this study is to demonstrate how value-based design can contribute to the design of mobility aids that address real needs and thus, lead to high acceptance. We elicited values, facilitators, and barriers of mobility of older adults via ten in-depth interviews. Next, we held co-creation sessions, resulting in several designs of innovative mobility aids, which were evaluated for acceptance via nine in-depth interviews. The interviews resulted in a myriad of key values, such as "independence from family" and "doing their own groceries." Design sessions resulted in three designs for a wheeled walker. Their acceptance was rather low. Current mobility device users were more eager to accept the designs than non-users. The value-based approach offers designers a close look into the lives of the elderly, thereby opening up a wide range of innovation possibilities that better fit their actual needs. Product service systems seem to be a promising focus for targeting human needs in mobility device design.

Learning and Prediction of Slip from Visual Information

NASA Technical Reports Server (NTRS)

Angelova, Anelia; Matthies, Larry; Helmick, Daniel; Perona, Pietro

2007-01-01

This paper presents an approach for slip prediction from a distance for wheeled ground robots using visual information as input. Large amounts of slippage which can occur on certain surfaces, such as sandy slopes, will negatively affect rover mobility. Therefore, obtaining information about slip before entering such terrain can be very useful for better planning and avoiding these areas. To address this problem, terrain appearance and geometry information about map cells are correlated to the slip measured by the rover while traversing each cell. This relationship is learned from previous experience, so slip can be predicted remotely from visual information only. The proposed method consists of terrain type recognition and nonlinear regression modeling. The method has been implemented and tested offline on several off-road terrains including: soil, sand, gravel, and woodchips. The final slip prediction error is about 20%. The system is intended for improved navigation on steep slopes and rough terrain for Mars rovers.

Influence of the track quality and of the properties of the wheel-rail rolling contact on vehicle dynamics

NASA Astrophysics Data System (ADS)

Suarez, Berta; Felez, Jesus; Lozano, José Antonio; Rodriguez, Pablo

2013-02-01

This work describes an analytical approach to determine what degree of accuracy is required in the definition of the rail vehicle models used for dynamic simulations. This way it would be possible to know in advance how the results of simulations may be altered due to the existence of errors in the creation of rolling stock models, whilst also identifying their critical parameters. This would make it possible to maximise the time available to enhance dynamic analysis and focus efforts on factors that are strictly necessary. In particular, the parameters related both to the track quality and to the rolling contact were considered in this study. With this aim, a sensitivity analysis was performed to assess their influence on the vehicle dynamic behaviour. To do this, 72 dynamic simulations were performed modifying, one at a time, the track quality, the wheel-rail friction coefficient and the equivalent conicity of both new and worn wheels. Three values were assigned to each parameter, and two wear states were considered for each type of wheel, one for new wheels and another one for reprofiled wheels. After processing the results of these simulations, it was concluded that all the parameters considered show very high influence, though the friction coefficient shows the highest influence. Therefore, it is recommended to undertake any future simulation job with measured track geometry and track irregularities, measured wheel profiles and normative values of the wheel-rail friction coefficient.

The Matsu Wheel: A Cloud-Based Framework for Efficient Analysis and Reanalysis of Earth Satellite Imagery

NASA Technical Reports Server (NTRS)

Patterson, Maria T.; Anderson, Nicholas; Bennett, Collin; Bruggemann, Jacob; Grossman, Robert L.; Handy, Matthew; Ly, Vuong; Mandl, Daniel J.; Pederson, Shane; Pivarski, James;

Optimisation of active suspension control inputs for improved vehicle ride performance

NASA Astrophysics Data System (ADS)

Čorić, Mirko; Deur, Joško; Xu, Li; Tseng, H. Eric; Hrovat, Davor

2016-07-01

A collocation-type control variable optimisation method is used in the paper to analyse to which extent the fully active suspension (FAS) can improve the vehicle ride comfort while preserving the wheel holding ability. The method is first applied for a cosine-shaped bump road disturbance of different heights, and for both quarter-car and full 10 degree-of-freedom vehicle models. A nonlinear anti-wheel hop constraint is considered, and the influence of bump preview time period is analysed. The analysis is then extended to the case of square- or cosine-shaped pothole with different lengths, and the quarter-car model. In this case, the cost function is extended with FAS energy consumption and wheel damage resilience costs. The FAS action is found to be such to provide a wheel hop over the pothole, in order to avoid or minimise the damage at the pothole trailing edge. In the case of long pothole, when the FAS cannot provide the wheel hop, the wheel is travelling over the pothole bottom and then hops over the pothole trailing edge. The numerical optimisation results are accompanied by a simplified algebraic analysis.

Tilted wheel satellite attitude control with air-bearing table experimental results

NASA Astrophysics Data System (ADS)

Inumoh, Lawrence O.; Forshaw, Jason L.; Horri, Nadjim M.

2015-12-01

Gyroscopic actuators for satellite control have attracted significant research interest over the years, but their viability for the control of small satellites has only recently started to become clear. Research on variable speed gyroscopic actuators has long been focused on single gimbal actuators; double gimbal actuators typically operate at constant wheel spin rate and allow tilt angle ranges far larger than the ranges needed to operate most satellite missions. This research examines a tilted wheel, a newly proposed type of inertial actuator that can generate torques in all three principal axes of a rigid satellite using a spinning wheel and a double tilt mechanism. The tilt mechanism tilts the angular momentum vector about two axes providing two degree of freedom control, while variation of the wheel speed provides the third. The equations of motion of the system lead to a singularity-free system during nominal operation avoiding the need for complex steering logic. This paper describes the hardware design of the tilted wheel and the experimental setup behind both standalone and spherical air-bearing tables used to test it. Experimental results from the air bearing table are provided with the results depicting the high performance capabilities of the proposed actuator in torque generation.

Analysis and design of a capsule landing system and surface vehicle control system for Mars exporation

NASA Technical Reports Server (NTRS)

Frederick, D. K.; Lashmet, P. K.; Sandor, G. N.; Shen, C. N.; Smith, E. J.; Yerazunis, S. W.

1972-01-01

The problems related to the design and control of a mobile planetary vehicle to implement a systematic plan for the exploration of Mars were investigated. Problem areas receiving attention include: vehicle configuration, control, dynamics, systems and propulsion; systems analysis; navigation, terrain modeling and path selection; and chemical analysis of specimens. The following specific tasks were studied: vehicle model design, mathematical modeling of dynamic vehicle, experimental vehicle dynamics, obstacle negotiation, electromechanical controls, collapsibility and deployment, construction of a wheel tester, wheel analysis, payload design, system design optimization, effect of design assumptions, accessory optimal design, on-board computer subsystem, laser range measurement, discrete obstacle detection, obstacle detection systems, terrain modeling, path selection system simulation and evaluation, gas chromatograph/mass spectrometer system concepts, chromatograph model evaluation and improvement and transport parameter evaluation.

Analysis and design of a capsule landing system and surface vehicle control system for Mars exploration

NASA Technical Reports Server (NTRS)

Frederick, D. K.; Lashmet, P. K.; Sandor, G. N.; Shen, C. N.; Smith, E. J.; Yerazunis, S. W.

1972-01-01

Investigation of problems related to the design and control of a mobile planetary vehicle to implement a systematic plan for the exploration of Mars has been undertaken. Problem areas receiving attention include: vehicle configuration, control, dynamics, systems and propulsion; systems analysis; terrain modeling and path selection; and chemical analysis of specimens. The following specific tasks have been under study: vehicle model design, mathematical modeling of a dynamic vehicle, experimental vehicle dynamics, obstacle negotiation, electromechanical controls, collapsibility and deployment, construction of a wheel tester, wheel analysis, payload design, system design optimization, effect of design assumptions, accessory optimal design, on-board computer sybsystem, laser range measurement, discrete obstacle detection, obstacle detection systems, terrain modeling, path selection system simulation and evaluation, gas chromatograph/mass spectrometer system concepts, chromatograph model evaluation and improvement.

Circulating levels of endocannabinoids respond acutely to voluntary exercise, are altered in mice selectively bred for high voluntary wheel running, and differ between the sexes

PubMed Central

Thompson, Zoe; Argueta, Donovan; Garland, Theodore; DiPatrizio, Nicholas

2017-01-01

The endocannabinoid system serves many physiological roles, including in the regulation of energy balance, food reward, and voluntary locomotion. Signaling at the cannabinoid type 1 receptor has been specifically implicated in motivation for rodent voluntary exercise on wheels. We studied four replicate lines of high runner (HR) mice that have been selectively bred for 81 generations based on average number of wheel revolutions on days five and six of a six-day period of wheel access. Four additional replicate lines are bred without regard to wheel running, and serve as controls (C) for random genetic effects that may cause divergence among lines. On average, mice from HR lines voluntarily run on wheels three times more than C mice on a daily basis. We tested the general hypothesis that circulating levels of endocannabinoids (i.e., 2-arachidonoylglycerol [2-AG] and anandamide [AEA]) differ between HR and C mice in a sex-specific manner. Fifty male and 50 female mice were allowed access to wheels for six days, while another 50 males and 50 females were kept without access to wheels (half HR, half C for all groups). Blood was collected by cardiac puncture during the time of peak running on the sixth night of wheel access or no wheel access, and later analyzed for 2-AG and AEA content by ultra-performance liquid chromatography coupled to tandem mass spectrometry. We observed a significant three-way interaction among sex, linetype, and wheel access for 2-AG concentrations, with females generally having lower levels than males and wheel access lowering 2-AG levels in some but not all subgroups. The number of wheel revolutions in the minutes or hours immediately prior to sampling did not quantitatively predict plasma 2-AG levels within groups. We also observed a trend for a linetype-by-wheel access interaction for AEA levels, with wheel access lowering plasma concentrations of AEA in HR mice, while raising them in C mice. In addition, females tended to have higher AEA concentrations than males. For mice housed with wheels, the amount of running during the 30 minutes before sampling was a significant positive predictor of plasma AEA within groups, and HR mice had significantly lower levels of AEA than C mice. Our results suggest that voluntary exercise alters circulating levels of endocannabinoids, and further demonstrate that selective breeding for voluntary exercise is associated with evolutionary changes in the endocannabinoid system. PMID:28017680

Circulating levels of endocannabinoids respond acutely to voluntary exercise, are altered in mice selectively bred for high voluntary wheel running, and differ between the sexes.

PubMed

Thompson, Zoe; Argueta, Donovan; Garland, Theodore; DiPatrizio, Nicholas

2017-03-01

The endocannabinoid system serves many physiological roles, including in the regulation of energy balance, food reward, and voluntary locomotion. Signaling at the cannabinoid type 1 receptor has been specifically implicated in motivation for rodent voluntary exercise on wheels. We studied four replicate lines of high runner (HR) mice that have been selectively bred for 81 generations based on average number of wheel revolutions on days five and six of a six-day period of wheel access. Four additional replicate lines are bred without regard to wheel running, and serve as controls (C) for random genetic effects that may cause divergence among lines. On average, mice from HR lines voluntarily run on wheels three times more than C mice on a daily basis. We tested the general hypothesis that circulating levels of endocannabinoids (i.e., 2-arachidonoylglycerol [2-AG] and anandamide [AEA]) differ between HR and C mice in a sex-specific manner. Fifty male and 50 female mice were allowed access to wheels for six days, while another 50 males and 50 females were kept without access to wheels (half HR, half C for all groups). Blood was collected by cardiac puncture during the time of peak running on the sixth night of wheel access or no wheel access, and later analyzed for 2-AG and AEA content by ultra-performance liquid chromatography coupled to tandem mass spectrometry. We observed a significant three-way interaction among sex, linetype, and wheel access for 2-AG concentrations, with females generally having lower levels than males and wheel access lowering 2-AG levels in some but not all subgroups. The number of wheel revolutions in the minutes or hours immediately prior to sampling did not quantitatively predict plasma 2-AG levels within groups. We also observed a trend for a linetype-by-wheel access interaction for AEA levels, with wheel access lowering plasma concentrations of AEA in HR mice, while raising them in C mice. In addition, females tended to have higher AEA concentrations than males. For mice housed with wheels, the amount of running during the 30min before sampling was a significant positive predictor of plasma AEA within groups, and HR mice had significantly lower levels of AEA than C mice. Our results suggest that voluntary exercise alters circulating levels of endocannabinoids, and further demonstrate that selective breeding for voluntary exercise is associated with evolutionary changes in the endocannabinoid system. Copyright © 2016 Elsevier Inc. All rights reserved.

Dynamic Performance of Subway Vehicle with Linear Induction Motor System

NASA Astrophysics Data System (ADS)

Wu, Pingbo; Luo, Ren; Hu, Yan; Zeng, Jing

The light rail vehicle with Linear Induction Motor (LIM) bogie, which is a new type of urban rail traffic tool, has the advantages of low costs, wide applicability, low noise, simple maintenance and better dynamic behavior. This kind of vehicle, supported and guided by the wheel and rail, is not driven by the wheel/rail adhesion force, but driven by the electromagnetic force between LIM and reaction plate. In this paper, three different types of suspensions and their characteristic are discussed with considering the interactions both between wheel and rail and between LIM and reaction plate. A nonlinear mathematical model of the vehicle with LIM bogie is set up by using the software SIMPACK, and the electromechanical model is also set up on Simulink roof. Then the running behavior of the LIM vehicle is simulated, and the influence of suspension on the vehicle dynamic performance is investigated.

A Study of a Handrim-Activated Power-Assist Wheelchair Based on a Non-Contact Torque Sensor

PubMed Central

Nam, Ki-Tae; Jang, Dae-Jin; Kim, Yong Chol; Heo, Yoon; Hong, Eung-Pyo

2016-01-01

Demand for wheelchairs is increasing with growing numbers of aged and disabled persons. Manual wheelchairs are the most commonly used assistive device for mobility because they are convenient to transport. Manual wheelchairs have several advantages but are not easy to use for the elderly or those who lack muscular strength. Therefore, handrim-activated power-assist wheelchairs (HAPAW) that can aid driving power with a motor by detecting user driving intentions through the handrim are being researched. This research will be on HAPAW that judge user driving intentions by using non-contact torque sensors. To deliver the desired motion, which is sensed from handrim rotation relative to a fixed controller, a new driving wheel mechanism is designed by applying a non-contact torque sensor, and corresponding torques are simulated. Torques are measured by a driving wheel prototype and compared with simulation results. The HAPAW prototype was developed using the wheels and a driving control algorithm that uses left and right input torques and time differences are used to check if the non-contact torque sensor can distinguish users’ driving intentions. Through this procedure, it was confirmed that the proposed sensor can be used effectively in HAPAW. PMID:27509508

Increasing the Mobility of Dismounted Marines

DTIC Science & Technology

2009-10-01

actually been the inspiration for military UGV development programs, including the Defense Advanced Research Projects Agency’s (DARPA) Legged Squad Support...or wheel-based; only the BigDog is a leg -based system. This presented BigDog with certain advantages (particularly involving its ability to traverse...1,000 pounds) Website: http://www.dtiweb.net/index.html 50 General Discussion: Ranlo The Ranlo – named after Defense Technologies, Inc.’s ( DTI

Design and evaluation of a seat orientation controller during uneven terrain driving.

PubMed

Candiotti, Jorge; Wang, Hongwu; Chung, Cheng-Shiu; Kamaraj, Deepan C; Grindle, Garrett G; Shino, Motoki; Cooper, Rory A

2016-03-01

Electric powered wheelchairs (EPWs) are essential devices for people with disabilities as aids for mobility and quality of life improvement. However, the design of currently available common EPWs is still limited and makes it challenging for the users to drive in both indoor and outdoor environments such as uneven surfaces, steep hills, or cross slopes, making EPWs susceptible to loss of stability and at risk for falls. An alternative wheel-legged robotic wheelchair, "MEBot", was designed to improve the safety and mobility of EPW users in both indoor and outdoor environments. MEBot is able to elevate its six wheels using pneumatic actuators, as well to detect changes in the seat angle using a gyroscope and accelerometer. This capability enables MEBot to provide sensing for a dynamic self-leveling seat application that can maintain the center of mass within the boundaries of the wheelchair, thereby, improving EPW safety. To verify the effectiveness of the application, MEBot was tested on a motion platform with six degrees of freedom to simulate different slopes that could be experienced by the EPW in outdoor environments. The results demonstrate the robustness of the application to maintain the wheelchair seat in a horizontal reference against changes in the ground angle. Published by Elsevier Ltd.

Dopamine D3 receptor status modulates sexual dimorphism in voluntary wheel running behavior in mice.

PubMed

Klinker, Florian; Ko Hnemann, Kathrin; Paulus, Walter; Liebetanz, David

2017-08-30

Sexual dimorphism has been described in various aspects of physiological and pathophysiological processes involving dopaminergic signaling. This might account for the different disease characteristics in men and women in e.g. Parkinson's disease or ADHD. A better understanding might contribute to the future individualization of therapy. We examined spontaneous wheel running activity of male and female mice, homo- and heterozygote for dopamine D3 receptor deficiency (D3R -/- and D3R+/-), and compared them to wild type controls. We found higher wheel running activity in female mice than in their male littermates. D3-/- mice, irrespective of sex, were also hyperactive compared to both D3+/- and wild type animals. Hyperactivity of D3-/- female mice was pronounced during the first days of wheel running but then decreased while their male counterparts continued to be hyperactive. Physical activity was menstrual cycle-dependent. Activity fluctuations were also seen in D3 receptor knockout mice and are therefore presumably independent of D3 receptor activation. Our data underscore the complex interaction of dopaminergic signaling and gonadal hormones that leads to specific running behavior. Furthermore, we detected sex- and D3 receptor status-specific reactions during novel exposure to the running wheel. These findings suggest the need for adapting dopaminergic therapies to individual factors such as sex or even menstrual cycle to optimize therapeutic success. Copyright © 2017 Elsevier B.V. All rights reserved.

A Feasability Study of the Wheel Electrostatic Spectrometer

NASA Technical Reports Server (NTRS)

Johansen, Michael Ryan; Phillips, James Ralph; Kelley, Joshua David; Mackey, Paul J.; Holbert, Eirik; Clements, Gregory R.; Calle, Carlos I.

2014-01-01

Mars rover missions rely on time-consuming, power-exhausting processes to analyze the Martian regolith. A low power electrostatic sensor in the wheels of a future Mars rover could be used to quickly determine when the rover is driving over a different type of regolith. The Electrostatics and Surface Physics Laboratory at NASA's Kennedy Space Center developed the Wheel Electrostatic Spectrometer as a feasibility study to investigate this option. In this paper, we discuss recent advances in this technology to increase the repeatability of the tribocharging experiments, along with supporting data. In addition, we discuss the development of a static elimination tool optimized for Martian conditions.

UMDNJ school of nursing mobile healthcare project: a component of the New Jersey Children's Health Project.

PubMed

McNeal, Gloria J

2008-01-01

This article describes a mobile ambulatory care nurse-managed center on wheels designed to address the healthcare needs of at-risk inner city residents. A grant-funded initiative, the Project uniquely joins nursing academe with community-based organizations in a partnership that brings healthcare services directly to those communities most in need. In addition to providing healthcare services, the Project serves as a site for faculty practice and community clinical rotations for nursing and medical students. The broad objectives of this nurse-faculty managed mobile healthcare project are: (1) to screen, identify and provide health promotion/disease management services for at-risk populations, (2) to foster community involvement in the health assessment and referral process; and, (3) to provide culturally and linguistically sensitive health promotion/disease management health education.

System design of a hand-held mobile robot for craniotomy.

PubMed

Kane, Gavin; Eggers, Georg; Boesecke, Robert; Raczkowsky, Jörg; Wörn, Heinz; Marmulla, Rüdiger; Mühling, Joachim

2009-01-01

This contribution reports the development and initial testing of a Mobile Robot System for Surgical Craniotomy, the Craniostar. A kinematic system based on a unicycle robot is analysed to provide local positioning through two spiked wheels gripping directly onto a patients skull. A control system based on a shared control system between both the Surgeon and Robot is employed in a hand-held design that is tested initially on plastic phantom and swine skulls. Results indicate that the system has substantially lower risk than present robotically assisted craniotomies, and despite being a hand-held mobile robot, the Craniostar is still capable of sub-millimetre accuracy in tracking along a trajectory and thus achieving an accurate transfer of pre-surgical plan to the operating room procedure, without the large impact of current medical robots based on modified industrial robots.

Use of the INDEPENDENCE 3000 IBOT Transporter at home and in the community: a case report.

PubMed

Cooper, Rory A; Boninger, Michael L; Cooper, Rosemarie; Kelleher, Annmarie

2006-01-01

The INDEPENDENCE 3000 IBOT Transporter (IBOT), as an electronically stabilized mobility device for people with disabilities. The purpose of this study was to gain experience with the IBOT at home and in the community using an expert wheelchair user, who used the device as his primary mobility device for 1 week. This case report is based upon observations by trained clinicians, and a diary recorded by the primary author a male manual wheelchair user with traumatic spinal cord injury at the T7/8 level. The subject was 41 years of age and 21 years post SCI at the time of the study. The participant was employed and lived in a ranch style accessible home. The subject used the devices to perform a variety of activities including holding eye-level discussions with colleagues and shopping by balancing on two wheels, going up and down steep ramps, traversing outdoor surfaces (e.g., grass, dirt trails) and climbing curbs. The balance and four-wheel drive functions were helpful and worked well. The IBOT was somewhat difficult to control in standard function. The seat height was too high for most tables and desks encountered, and transfers were notably more difficult than with other wheelchairs. It was difficult to use the IBOT in the bathroom, and the subject preferred to use his personal wheelchairs for transfers into the shower. The IBOT was a functional mobility device, its greatest strengths are outdoors and in circumstances where there is space to use balance function.

Sediment production from forest roads with wheel ruts

Treesearch

Randy B. Foltz; Edward R. Burroughs

1990-01-01

Artificial rainfall was applied to two sets of paired plots 30.5 m long by 1.52 m wide, each set on a different soil type. One plot in each set contained a wheel rut while the other did not. Measurements of water and sediment yield on rutted plots showed sediment production declined with cumulative runoff while unrutted plots did not show a significant sediment...

Optimization of wheel-rail interface friction using top-of-rail friction modifiers: State of the art

NASA Astrophysics Data System (ADS)

Khan, M. Roshan; Dasaka, Satyanarayana Murty

2018-05-01

High Speed Railways and Dedicated Freight Corridors are the need of the day for fast and efficient transportation of the ever growing population and freight across long distances of travel. With the increase in speeds and axle loads carried by these trains, wearing out of rails and train wheel sections are a common issue, which is due to the increase in friction at the wheel-rail interfaces. For the cases where the wheel-rail interface friction is less than optimum, as in case of high speed trains with very low axle loads, wheel-slips are imminent and loss of traction occurs when the trains accelerate rapidly or brake all of a sudden. These vast variety of traction problems around the wheel-rail interface friction need to be mitigated carefully, so that the contact interface friction neither ascents too high to cause material wear and need for added locomotive power, nor be on the lower side to cause wheel-slips and loss of traction at high speeds. Top-of-rail friction modifiers are engineered surface coatings applied on top of rails, to maintain an optimum frictional contact between the train wheels and the rails. Extensive research works in the area of wheel-rail tribology have revealed that the optimum frictional coefficients at wheel-rail interfaces lie at a value of around 0.35. Application of top-of-rail (TOR) friction modifiers on rail surfaces add an extra layer of material coating on top of the rails, with a surface frictional coefficient of the desired range. This study reviews the common types of rail friction modifiers, the methods for their application, issues related with the application of friction modifiers, and a guideline on selection of the right class of coating material based on site specific requirements of the railway networks.

A new type of magnetic gimballed momentum wheel and its application to attitude control in space

NASA Astrophysics Data System (ADS)

Murakami, C.; Ohkami, Y.; Okamoto, O.; Nakajima, A.; Inoue, M.; Tsuchiya, J.; Yabu-uchi, K.; Akishita, S.; Kida, T.

A new type of magnetically suspended gimbal momentum wheel utilizing permanent magnets is described. The bearing was composed of four independent thrust actuators which control the rotor thrust position and gimbal angles cooperatively, so that the bearing comes to have a simple mechanism with high reliability and light weight. The high speed instability problem due to the internal damping was easily overcome by introducing anisotropic radial stiffness. A momentum flywheel with the 3-axis controlled magnetic bearing displays good performance for attitude control of satellite with biased momentum.

A Study on the Internal Structure of Heumgyeonggaknu

NASA Astrophysics Data System (ADS)

Kim, Sang Hyuk; Lee, Yong Sam; Lee, Min Soo; Ham, Sun Young

2013-06-01

Heumgyeonggaknu is a water-hammering type automatic water clock which was made by Jang Yeong-Sil in 1438. The water clock that is located in Heumgyeonggaknu consists of Suho which is equipped with 2-stage overflow. Constant water wheel power is generated by supplying a fixed amount of water of Suho to Sususang, and this power is transferred to each floor at the same time. The 1st floor rotation wheel of Gasan consists of the operation structure which has the shape of umbrella ribs. The 2nd floor rotation wheel is made so that the 12 hour signal, Gyeong-Jeom signal, and Jujeon constitute a systematic configuration. The 3rd floor rotation wheel is made so that the signal and rotation of Ongnyeo and four gods can be accomplished. Based on the above conceptual design, this paper analyzed the internal signal generation and power transmission of Heumgyeonggaknu.

Flocking of multiple mobile robots based on backstepping.

PubMed

Dong, Wenjie

2011-04-01

This paper considers the flocking of multiple nonholonomic wheeled mobile robots. Distributed controllers are proposed with the aid of backstepping techniques, results from graph theory, and singular perturbation theory. The proposed controllers can make the states of a group of robots converge to a desired geometric pattern whose centroid moves along a desired trajectory under the condition that the desired trajectory is available to a portion of the group of robots. Since communication delay is inevitable in distributed control, its effect on the performance of the closed-loop systems is analyzed. It is shown that the proposed controllers work well if communication delays are constant. To show effectiveness of the proposed controllers, simulation results are included.

Agile and dexterous robot for inspection and EOD operations

NASA Astrophysics Data System (ADS)

Handelman, David A.; Franken, Gordon H.; Komsuoglu, Haldun

2010-04-01

The All-Terrain Biped (ATB) robot is an unmanned ground vehicle with arms, legs and wheels designed to drive, crawl, walk and manipulate objects for inspection and explosive ordnance disposal tasks. This paper summarizes on-going development of the ATB platform. Control technology for semi-autonomous legged mobility and dual-arm dexterity is described as well as preliminary simulation and hardware test results. Performance goals include driving on flat terrain, crawling on steep terrain, walking on stairs, opening doors and grasping objects. Anticipated benefits of the adaptive mobility and dexterity of the ATB platform include increased robot agility and autonomy for EOD operations, reduced operator workload and reduced operator training and skill requirements.

Bucket wheel rehabilitation of ERC 1400-30/7 high-capacity excavators from lignite quarries

NASA Astrophysics Data System (ADS)

Vîlceanu, Fl; Iancu, C.

2016-11-01

The existence of bucket wheel equipment type ERC 1400-30/7 in lignite quarries with lifetime expired, or in the ultimate life period, together with high cost investments for their replacement, makes rational the efforts made to rehabilitation in order to extend their life. Rehabilitation involves checking operational safety based on relevant expertise of metal structures supporting effective resistance but also the replacement (or modernization) of subassemblies that can increase excavation process productivity, lowering energy consumption, reducing mechanical stresses. This paper proposes an analysis of constructive solution of using a part of the classical bucket wheel, on which are located 9 cutting cups and 9 chargers cups and adding a new part so that the new redesigned bucket-wheel will contain 18 cutting-chargers cups, compared to the classical model. On the CAD model of bucket wheel was performed a static and a dynamic FEA, the results being compared with the yield strength of the material of the entire structure, were checked mechanical stresses in the overall distribution map, and were verified the first 4 vibrating modes the structure compared to real loads. Thus was verified that the redesigned bucket-wheel can accomplish the proposed goals respectively increase excavation process productivity, lowering energy consumption and reducing mechanical stresses.

Responding for sucrose and wheel-running reinforcement: effect of pre-running.

PubMed

Belke, Terry W

2006-01-10

Six male albino Wistar rats were placed in running wheels and exposed to a fixed interval 30-s schedule that produced either a drop of 15% sucrose solution or the opportunity to run for 15s as reinforcing consequences for lever pressing. Each reinforcer type was signaled by a different stimulus. To assess the effect of pre-running, animals were allowed to run for 1h prior to a session of responding for sucrose and running. Results showed that, after pre-running, response rates in the later segments of the 30-s schedule decreased in the presence of a wheel-running stimulus and increased in the presence of a sucrose stimulus. Wheel-running rates were not affected. Analysis of mean post-reinforcement pauses (PRP) broken down by transitions between successive reinforcers revealed that pre-running lengthened pausing in the presence of the stimulus signaling wheel running and shortened pauses in the presence of the stimulus signaling sucrose. No effect was observed on local response rates. Changes in pausing in the presence of stimuli signaling the two reinforcers were consistent with a decrease in the reinforcing efficacy of wheel running and an increase in the reinforcing efficacy of sucrose. Pre-running decreased motivation to respond for running, but increased motivation to work for food.

Applying FastSLAM to Articulated Rovers

NASA Astrophysics Data System (ADS)

Hewitt, Robert Alexander

This thesis presents the navigation algorithms designed for use on Kapvik, a 30 kg planetary micro-rover built for the Canadian Space Agency; the simulations used to test the algorithm; and novel techniques for terrain classification using Kapvik's LIDAR (Light Detection And Ranging) sensor. Kapvik implements a six-wheeled, skid-steered, rocker-bogie mobility system. This warrants a more complicated kinematic model for navigation than a typical 4-wheel differential drive system. The design of a 3D navigation algorithm is presented that includes nonlinear Kalman filtering and Simultaneous Localization and Mapping (SLAM). A neural network for terrain classification is used to improve navigation performance. Simulation is used to train the neural network and validate the navigation algorithms. Real world tests of the terrain classification algorithm validate the use of simulation for training and the improvement to SLAM through the reduction of extraneous LIDAR measurements in each scan.

An intelligent rollator for mobility impaired persons, especially stroke patients.

PubMed

Hellström, Thomas; Lindahl, Olof; Bäcklund, Tomas; Karlsson, Marcus; Hohnloser, Peter; Bråndal, Anna; Hu, Xiaolei; Wester, Per

2016-07-01

An intelligent rollator (IRO) was developed that aims at obstacle detection and guidance to avoid collisions and accidental falls. The IRO is a retrofit four-wheeled rollator with an embedded computer, two solenoid brakes, rotation sensors on the wheels and IR-distance sensors. The value reported by each distance sensor was compared in the computer to a nominal distance. Deviations indicated a present obstacle and caused activation of one of the brakes in order to influence the direction of motion to avoid the obstacle. The IRO was tested by seven healthy subjects with simulated restricted and blurred sight and five stroke subjects on a standardised indoor track with obstacles. All tested subjects walked faster with intelligence deactivated. Three out of five stroke patients experienced more detected obstacles with intelligence activated. This suggests enhanced safety during walking with IRO. Further studies are required to explore the full value of the IRO.

Unscented Kalman Filter-Trained Neural Networks for Slip Model Prediction

PubMed Central

Li, Zhencai; Wang, Yang; Liu, Zhen

2016-01-01

The purpose of this work is to investigate the accurate trajectory tracking control of a wheeled mobile robot (WMR) based on the slip model prediction. Generally, a nonholonomic WMR may increase the slippage risk, when traveling on outdoor unstructured terrain (such as longitudinal and lateral slippage of wheels). In order to control a WMR stably and accurately under the effect of slippage, an unscented Kalman filter and neural networks (NNs) are applied to estimate the slip model in real time. This method exploits the model approximating capabilities of nonlinear state–space NN, and the unscented Kalman filter is used to train NN’s weights online. The slip parameters can be estimated and used to predict the time series of deviation velocity, which can be used to compensate control inputs of a WMR. The results of numerical simulation show that the desired trajectory tracking control can be performed by predicting the nonlinear slip model. PMID:27467703

Dynamic modelling and experimental validation of three wheeled tilting vehicles

NASA Astrophysics Data System (ADS)

Amati, Nicola; Festini, Andrea; Pelizza, Luigi; Tonoli, Andrea

2011-06-01

The present paper describes the study of the stability in the straight running of a three-wheeled tilting vehicle for urban and sub-urban mobility. The analysis was carried out by developing a multibody model in the Matlab/SimulinkSimMechanics environment. An Adams-Motorcycle model and an equivalent analytical model were developed for the cross-validation and for highlighting the similarities with the lateral dynamics of motorcycles. Field tests were carried out to validate the model and identify some critical parameters, such as the damping on the steering system. The stability analysis demonstrates that the lateral dynamic motions are characterised by vibration modes that are similar to that of a motorcycle. Additionally, it shows that the wobble mode is significantly affected by the castor trail, whereas it is only slightly affected by the dynamics of the front suspension. For the present case study, the frame compliance also has no influence on the weave and wobble.

Novel Control Scheme of Power Assisted Wheelchair for Preventing Overturn (Part I)-Adjustment of Assisted Torque and Performance Evaluation From Field Test-

NASA Astrophysics Data System (ADS)

Seki, Hirokazu; Hata, Naoki; Koyasu, Yuichi; Hori, Yoichi

Aged people and disabled people who have difficulty in walking are increasing. As one of mobility support, significance of power assisted wheelchair which assists driving force using electric motors and spreads their living areas has been enhanced. However, the increased driving force often causes a dangerous overturn of wheelchair. In this paper, control method to prevent power assisted wheelchair from overturning is proposed. It is found the front wheels rising is caused by magnitude and rapid increase of assisted torque. Therefore, feedforward control method to limit the assisted torque by tuning its magnitude or time constant is proposed. In order to emphasize safety and feeling of security, these methods make the front wheels no rise. The effectiveness of the proposed method is verified by the practical experiments and field test based performance evaluation using many trial subjects.

Voluntary Running Suppresses Tumor Growth through Epinephrine- and IL-6-Dependent NK Cell Mobilization and Redistribution.

PubMed

Pedersen, Line; Idorn, Manja; Olofsson, Gitte H; Lauenborg, Britt; Nookaew, Intawat; Hansen, Rasmus Hvass; Johannesen, Helle Hjorth; Becker, Jürgen C; Pedersen, Katrine S; Dethlefsen, Christine; Nielsen, Jens; Gehl, Julie; Pedersen, Bente K; Thor Straten, Per; Hojman, Pernille

2016-03-08

Regular exercise reduces the risk of cancer and disease recurrence. Yet the mechanisms behind this protection remain to be elucidated. In this study, tumor-bearing mice randomized to voluntary wheel running showed over 60% reduction in tumor incidence and growth across five different tumor models. Microarray analysis revealed training-induced upregulation of pathways associated with immune function. NK cell infiltration was significantly increased in tumors from running mice, whereas depletion of NK cells enhanced tumor growth and blunted the beneficial effects of exercise. Mechanistic analyses showed that NK cells were mobilized by epinephrine, and blockade of β-adrenergic signaling blunted training-dependent tumor inhibition. Moreover, epinephrine induced a selective mobilization of IL-6-sensitive NK cells, and IL-6-blocking antibodies blunted training-induced tumor suppression, intratumoral NK cell infiltration, and NK cell activation. Together, these results link exercise, epinephrine, and IL-6 to NK cell mobilization and redistribution, and ultimately to control of tumor growth. Copyright © 2016 Elsevier Inc. All rights reserved.

Development and Control of Multi-Degree-of-Freedom Mobile Robot for Acquisition of Road Environmental Modes

NASA Astrophysics Data System (ADS)

Murata, Naoya; Katsura, Seiichiro

Acquisition of information about the environment around a mobile robot is important for purposes such as controlling the robot from a remote location and in situations such as that when the robot is running autonomously. In many researches, audiovisual information is used. However, acquisition of information about force sensation, which is included in environmental information, has not been well researched. The mobile-hapto, which is a remote control system with force information, has been proposed, but the robot used for the system can acquire only the horizontal component of forces. For this reason, in this research, a three-wheeled mobile robot that consists of seven actuators was developed and its control system was constructed. It can get information on horizontal and vertical forces without using force sensors. By using this robot, detailed information on the forces in the environment can be acquired and the operability of the robot and its capability to adjust to the environment are expected to improve.

Application of neural models as controllers in mobile robot velocity control loop

NASA Astrophysics Data System (ADS)

Cerkala, Jakub; Jadlovska, Anna

2017-01-01

This paper presents the application of an inverse neural models used as controllers in comparison to classical PI controllers for velocity tracking control task used in two-wheel, differentially driven mobile robot. The PI controller synthesis is based on linear approximation of actuators with equivalent load. In order to obtain relevant datasets for training of feed-forward multi-layer perceptron based neural network used as neural model, the mathematical model of mobile robot, that combines its kinematic and dynamic properties such as chassis dimensions, center of gravity offset, friction and actuator parameters is used. Neural models are trained off-line to act as an inverse dynamics of DC motors with particular load using data collected in simulation experiment for motor input voltage step changes within bounded operating area. The performances of PI controllers versus inverse neural models in mobile robot internal velocity control loops are demonstrated and compared in simulation experiment of navigation control task for line segment motion in plane.

Dual adaptive dynamic control of mobile robots using neural networks.

PubMed

Bugeja, Marvin K; Fabri, Simon G; Camilleri, Liberato

2009-02-01

This paper proposes two novel dual adaptive neural control schemes for the dynamic control of nonholonomic mobile robots. The two schemes are developed in discrete time, and the robot's nonlinear dynamic functions are assumed to be unknown. Gaussian radial basis function and sigmoidal multilayer perceptron neural networks are used for function approximation. In each scheme, the unknown network parameters are estimated stochastically in real time, and no preliminary offline neural network training is used. In contrast to other adaptive techniques hitherto proposed in the literature on mobile robots, the dual control laws presented in this paper do not rely on the heuristic certainty equivalence property but account for the uncertainty in the estimates. This results in a major improvement in tracking performance, despite the plant uncertainty and unmodeled dynamics. Monte Carlo simulation and statistical hypothesis testing are used to illustrate the effectiveness of the two proposed stochastic controllers as applied to the trajectory-tracking problem of a differentially driven wheeled mobile robot.

Combined EDL-Mobility Planning for Planetary Missions

NASA Technical Reports Server (NTRS)

Kuwata, Yoshiaki; Balaram, Bob

2011-01-01

This paper presents an analysis framework for planetary missions that have coupled mobility and EDL (Entry-Descent-Landing) systems. Traditional systems engineering approaches to mobility missions such as MERs (Mars Exploration Rovers) and MSL (Mars Science Laboratory) independently study the EDL system and the mobility system, and does not perform explicit trade-off between them or risk minimization of the overall system. A major challenge is that EDL operation is inherently uncertain and its analysis results such as landing footprint are described using PDF (Probability Density Function). The proposed approach first builds a mobility cost-to-go map that encodes the driving cost of any point on the map to a science target location. The cost could include variety of metrics such as traverse distance, time, wheel rotation on soft soil, and closeness to hazards. It then convolves the mobility cost-to-go map with the landing PDF given by the EDL system, which provides a histogram of driving cost, which can be used to evaluate the overall risk of the mission. By capturing the coupling between EDL and mobility explicitly, this analysis framework enables quantitative tradeoff between EDL and mobility system performance, as well as the characterization of risks in a statistical way. The simulation results are presented with a realistic Mars terrain data

Wheeled mobility: factors influencing mobility and assistive technology in veterans and servicemembers with major traumatic limb loss from Vietnam war and OIF/OEF conflicts.

PubMed

Laferrier, Justin Z; McFarland, Lynne V; Boninger, Michael L; Cooper, Rory A; Reiber, Gayle E

2010-01-01

Returning wounded veterans and servicemembers to their highest level of function following traumatic injury is a priority of the Departments of Defense and Veterans Affairs. We surveyed 245 veterans from the Vietnam war and 226 servicemembers and veterans from Operation Iraqi Freedom/Operation Enduring Freedom (OIF/OEF) conflicts with at least one major traumatic lower-limb loss to determine their use of mobility assistive technology (AT) and patterns of limb abandonment. Prosthetic device use without wheelchair use is found in 50.5% of Vietnam and 42.8% of OIF/OEF groups. Prostheses and supplementary wheelchairs are used by Vietnam (32%) and OIF/OEF (53%) groups (p < 0.01). Exclusive wheelchair use is more frequent in the Vietnam group (18%) than in the OIF/OEF group (4.0%, p < 0.01). In Vietnam participants, multivariate analysis found that multiple-limb loss (adjusted odds ratio [AOR] = 14.5; 95% confidence interval [CI] 5.5-38.5), bilateral lower-limb loss (AOR = 12.7; 95% CI 6.2-26.1), and number of comorbidities (AOR = 1.3; 95% CI 1.2-1.5) are associated with increased likelihood of wheelchair use. In OIF/OEF participants, bilateral lower-limb loss (AOR = 29.8; 95% CI 11.0-80.7), multiple-limb loss (AOR = 16.3; 95% CI 3.1-85.3), cumulative trauma disorder (AOR = 2.4; 95% CI 1.2-4.9), and number of combat injuries (AOR = 1.4; 95% CI 1.2-1.7) are associated with wheelchair use. Combined use of different types of mobility ATs promotes improved rehabilitation and ability to function.

Large Hexadecametallic {Mn(III) -Ln(III) } Wheels: Synthesis, Structural, Magnetic, and Theoretical Characterization.

PubMed

Vignesh, Kuduva R; Langley, Stuart K; Moubaraki, Boujemaa; Murray, Keith S; Rajaraman, Gopalan

2015-11-09

The synthesis, gas sorption studies, magnetic properties, and theoretical studies of new molecular wheels of core type {Mn(III) 8 Ln(III) 8 } (Ln=Dy, Ho, Er, Y and Yb), using the ligand mdeaH2 , in the presence of ortho-toluic or benzoic acid are reported. From the seven wheels studied the {Mn8 Dy8 } and {Mn8 Y8 } analogues exhibit SMM behavior as determined from ac susceptibility experiments in a zero static magnetic field. From DFT calculations a S=16 ground state was determined for the {Mn8 Y8 } complex due to weak ferromagnetic Mn(III) -Mn(III) interactions. Ab initio CASSCF+RASSI-SO calculations on the {Mn8 Dy8 } wheel estimated the Mn(III) -Dy(III) exchange interaction as -0.1 cm(-1) . This weak exchange along with unfavorable single-ion anisotropy of Dy(III) /Mn(III) ions, however, led to the observation of SMM behavior with fast magnetic relaxation. The orientation of the g-anisotropy of the Dy(III) ions is found to be perpendicular to the plane of the wheel and this suggests the possibility of toroidal magnetic moments in the cluster. The {Mn8 Ln8 } clusters reported here are the largest heterometallic Mn(III) Ln(III) wheels and the largest {3d-4f} wheels to exhibit SMM behavior reported to date. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Saturn Apollo Program

NASA Image and Video Library

1967-05-25

Artist’s concept of the Local Scientific Survey Module (LSSM), one of two designs for a Lunar Roving Vehicle (LRV), depicted on the lunar surface A Bendix Corporation concept, this configuration weighs more than 8,000 pounds, is 21-feet long, 15-feet wide and has 6 wheels with 5-foot diameters. The LRV was developed under the direction of the Marshall Space Flight Center (MSFC) to give Apollo astronauts a wider range of mobility on the lunar surface.

Field Organizations: Unit Status Reporting

DTIC Science & Technology

2001-11-15

3 15 PSYOP DEV DET Detachment CDR 12/8 15 TAC PSYOP DET Detachment CDR 13/8 15 TAC PSYOP team Team leader 5/3 15 UAV TBD TBD 16 MAV/ IAV TBD TBD 16 Fox...AR 600–110 Identification, Surveillance, and Administration of Personnel Infected with Human Immuno-deficiency Virus (HIV) AR 601–210 Regular Army...HIV human immunodeficiency virus HMMWV high mobility multipurpose wheeled vehicle HO hospitalized/convalescent leave category of personnel non

Improving Recapitalization Planning: Toward a Fleet Management Model for the High-Mobility Multipurpose Wheeled Vehicle

DTIC Science & Technology

2008-01-01

Information Operations and Reports, 1215 Jefferson Davis Highway, Suite 1204, Arlington VA 22202-4302. Respondents should be aware that notwithstanding...Planning: Toward a Fleet Management Model for the HMMWV For more information on RAND Arroyo Center, contact the Director of Operations (tele- phone 310-393...may benefit from additional information about the relationships between Army vehicle ages and operating costs and the practical implications of those

Small Craft Transportability Design and Certification Process Guidance. Revision B

DTIC Science & Technology

2010-11-08

49CFR393.104, wherever a tie-down strap is subject to abrasion or cutting, it should be provided with edge protection capable of resisting abrasion , cutting...commercial round connector shown in Figure 8. Tactical vehicles (e.g., MTVR, High Mobility Multi-Wheeled Vehicle (HMMWV), or Mine Resistant Ambush...a heavy-duty construction, using corrosion- and rot- resistant (or coated) materials and components. Trailer components are likely to be submerged

Mobility Performance Algorithms for Small Unmanned Ground Vehicles

DTIC Science & Technology

2009-05-01

obstacles need to be developed; specifically, models and data for wheeled vehicle skid steering, interior building floor and roof surfaces, and stair ...an 80-lb SUGV; PackBot® at 50 lb, and GatorTM at 2500 lb. Additionally, the FCS projects that 40% of the military fleet may eventually be robotic ...sensor input analysis and decision-making time. Fields (2002a) discusses representing interaction of humans and robots in the OneSAF Testbed Baseline

Modelling and Simulation in the Design Process of Armored Vehicles

DTIC Science & Technology

2003-03-01

trackway conditions is a demanding optimization task. Basically, a high level of ride comfort requires soft suspension tuning, whereas driving safety relies...The maximum off-road speed is generally limited by traction, input torque, driving safety and ride comfort. When obstacles are to be negotiated, the...wheel travel was defined during the mobility simulation runs. Figure 14: Ramp 1.5m at 40 kph; virtual and physical prototype Driving safety and ride

Advanced Suspension and Control Algorithm for U.S. Army Ground Vehicles

DTIC Science & Technology

2013-04-01

Army Materiel Systems Analysis Activity (AMSAA), for his assistance and guidance in building a multibody vehicle dynamics model of a typical light...Mobility Multipurpose Wheeled Vehicle [HMMWV] model) that was developed in collaboration with the U.S. Army Materiel Systems Analysis Activity (5) is...control weight for GPC With Explicit Disturbance was R = 1.0e-7 over the entire speed range. To simplify analysis , the control weights for the other two

Army Synthetic Validity Project Report of Phase 2 Results. Volume 3. Research Instruments

DTIC Science & Technology

1990-10-01

Areas 7. The type of secondary arms room lock shown at A in the diagram below requires rotation A. monthly B. quarterly C. semiannually D. annually E...building concrete, stone, or other structures (for example, roads, fortifications , buildings, etc.). 16. Operate wheeled vehicles - drive wheeled...for cover and concealment and to place weapons, fortifications , mines, and detectors. 64. Translate foreign languages - translate written or spoken

On the non-proportionality between wheel/rail contact forces and speed during wheelset passage over specific welds

NASA Astrophysics Data System (ADS)

Correa, Nekane; Vadillo, Ernesto G.; Santamaria, Javier; Blanco-Lorenzo, Julio

2018-01-01

This study investigates the influence on the wheel-rail contact forces of the running speed and the shape and position of weld defects along the track. For this purpose, a vertical dynamic model in the space domain is used. The model is obtained from the transformation between the domains of frequency and space using a Rational Fraction Polynomials (RFP) method, which is modified with multiobjective genetic algorithms in order to improve the fitting of track receptance and to assist integration during simulations. This produces a precise model with short calculation times, which is essential to this study. The wheel-rail contact is modelled using a non-linear Hertz spring. The contact forces are studied for several types of characteristic welds. The way in which forces vary as a function of weld position and running speed is studied for each type of weld. This paper studies some of the factors that affect the maximum forces when the vehicle moves over a rail weld, such as weld geometry, parametric excitation and contact stiffness. It is found that the maximum force in the wheel-rail contact when the vehicle moves over a weld is not always proportional to the running speed. The paper explains why it is not proportional in specific welds.

Effect of a redesigned two-wheeled container for refuse collecting on mechanical loading of low back and shoulders.

PubMed

Kuijer, P Paul F M; Hoozemans, Marco J M; Kingma, Idsart; Van Dieën, Jaap H; De Vries, Wiebe H K; Veeger, Dirk Jan; Van der Beek, Allard J; Visser, Bart; Frings-Dresen, Monique H W

2003-05-15

The objective of this study was to compare the mechanical and perceived workload when working with a redesigned two-wheeled container and working with a standard two-wheeled container for refuse collecting. The three changes in the design of the container were a displacement of the position of the centre of mass in the direction of the axis of the wheels, a slight increase in the height of the handle and a slight increase in the horizontal distance between the handle and the wheel-axis, and an increase in the diameter of the wheels. The volume of the container remained 0.240 m3. Nine refuse collectors performed some of their most frequent daily activities with both types of containers in the laboratory. Kinematics and exerted hand forces were assessed as input for detailed 3D biomechanical models of the low back and shoulder to estimate net moments at the low back and shoulders, compressive forces at the low back and contact forces at the glenohumeral joint. Also, the refuse collectors rated the ease of handling the two-wheeled containers on a five point scale. The use of the redesigned container resulted in a decrease of the exerted hand forces of 27%, decreases in the net moments at the low back and shoulders of 8% and 20%, respectively, and a decrease of 32% of the contact force at the glenohumeral joint when compared to the standard container. However, pulling an empty redesigned container on to the pavement resulted in an increase of the shoulder moment of more than 100%. No differences between container types were found for the compressive forces at the low back. Pushing and pulling with the redesigned container was rated as easier than pushing and pulling with the standard container. No differences in subjective ratings were found for the tasks of turning the container or pulling an empty container onto the pavement. It is concluded that, provided that empty containers are placed back onto the pavement as infrequently as possible, the introduction of the redesigned container could result in a reduction of the low back and shoulder load for refuse collectors.

Survey on utility technology of a tidal and ocean current energy

NASA Astrophysics Data System (ADS)

Hirose, Manabu; Kadoyu, Masataka; Tanaka, Hiroyoshi

1987-06-01

A study is made to show the current technological levels in Japan and other nations regarding the conversion of tidal current or ocean current energy to electric power and to determine the latent energy quantities and energy-related characteristics of tidal and ocean currents. In Japan, relatively large-scale experiments made so far mostly used one of the following three types of devices: Savonius-wheel type, Darrieus-wheel type, and cross-flow-wheel type. Field experiments of tidal energy conversion have been performed at the Naruto and Kurushima Straits. The energy in the Kuroshio current is estimated at about 170 billion kWh per year. Ocean current energy does not undergo large seasonal variations. The total energy in major straits and channels in the Inland Sea and other sea areas to the west is estimated at about 124 billion kWh per year. Tidal current energy shows large seasonal variations, but it is possible to predict the changes. A survey is made to determine energy-related characteristics of a tidal current at Chichino-seto, Kagoshima Prefecture. At Chichino-seto, the flow velocity ranges from 0 to 2.2m/s, with a latent tidal current energy of about 70 kW, of which about 20 kW can actually be utilized.

Online, efficient and precision laser profiling of bronze-bonded diamond grinding wheels based on a single-layer deep-cutting intermittent feeding method

NASA Astrophysics Data System (ADS)

Deng, Hui; Chen, Genyu; He, Jie; Zhou, Cong; Du, Han; Wang, Yanyi

2016-06-01

In this study, an online, efficient and precision laser profiling approach that is based on a single-layer deep-cutting intermittent feeding method is described. The effects of the laser cutting depth and the track-overlap ratio of the laser cutting on the efficiency, precision and quality of laser profiling were investigated. Experiments on the online profiling of bronze-bonded diamond grinding wheels were performed using a pulsed fiber laser. The results demonstrate that an increase in the laser cutting depth caused an increase in the material removal efficiency during the laser profiling process. However, the maximum laser profiling efficiency was only achieved when the laser cutting depth was equivalent to the initial surface contour error of the grinding wheel. In addition, the selection of relatively high track-overlap ratios of laser cutting for the profiling of grinding wheels was beneficial with respect to the increase in the precision of laser profiling, whereas the efficiency and quality of the laser profiling were not affected by the change in the track-overlap ratio. After optimized process parameters were employed for online laser profiling, the circular run-out error and the parallelism error of the grinding wheel surface decreased from 83.1 μm and 324.6 μm to 11.3 μm and 3.5 μm, respectively. The surface contour precision of the grinding wheel significantly improved. The highest surface contour precision for grinding wheels of the same type that can be theoretically achieved after laser profiling is completely dependent on the peak power density of the laser. The higher the laser peak power density is, the higher the surface contour precision of the grinding wheel after profiling.

Training a Network of Electronic Neurons for Control of a Mobile Robot

NASA Astrophysics Data System (ADS)

Vromen, T. G. M.; Steur, E.; Nijmeijer, H.

An adaptive training procedure is developed for a network of electronic neurons, which controls a mobile robot driving around in an unknown environment while avoiding obstacles. The neuronal network controls the angular velocity of the wheels of the robot based on the sensor readings. The nodes in the neuronal network controller are clusters of neurons rather than single neurons. The adaptive training procedure ensures that the input-output behavior of the clusters is identical, even though the constituting neurons are nonidentical and have, in isolation, nonidentical responses to the same input. In particular, we let the neurons interact via a diffusive coupling, and the proposed training procedure modifies the diffusion interaction weights such that the neurons behave synchronously with a predefined response. The working principle of the training procedure is experimentally validated and results of an experiment with a mobile robot that is completely autonomously driving in an unknown environment with obstacles are presented.

Impact of Mass and Weight Distribution on Manual Wheelchair Propulsion Torque.

PubMed

Sprigle, Stephen; Huang, Morris

2015-01-01

Propulsion effort of manual wheelchairs, a major determinant of user mobility, is a function of human biomechanics and mechanical design. Human studies that investigate both variables simultaneously have resulted in largely inconsistent outcomes, motivating the implementation of a robotic propulsion system that characterizes the inherent mechanical performance of wheelchairs. This study investigates the impacts of mass and mass distribution on manual wheelchair propulsion by configuring an ultra-lightweight chair to two weights (12-kg and 17.6-kg) and two load distributions (70% and 55% on drive wheels). The propulsion torques of these four configurations were measured for a straight maneuver and a fixed-wheel turn, on both tile and carpet. Results indicated that increasing mass to 17.6-kg had the largest effect on straight acceleration, requiring 7.4% and 5.8% more torque on tile and carpet, respectively. Reducing the drive wheel load to 55% had the largest effect on steady-state straight motion and on both turning acceleration and steady-state turning; for tile and carpet, propulsion torque increased by 13.5% and 11.8%, 16.5% and 4.1%, 73% and 5.1%, respectively. These results demonstrate the robot's high sensitivity, and support the clinical importance of evaluating effects of wheelchair mass and axle position on propulsion effort across maneuvers and surfaces.

Relationship between linear velocity and tangential push force while turning to change the direction of the manual wheelchair.

PubMed

Hwang, Seonhong; Lin, Yen-Sheng; Hogaboom, Nathan S; Wang, Lin-Hwa; Koontz, Alicia M

2017-08-28

Wheelchair propulsion is a major cause of upper limb pain and injuries for manual wheelchair users with spinal cord injuries (SCIs). Few studies have investigated wheelchair turning biomechanics on natural ground surfaces. The purpose of this study was to investigate the relationship between tangential push force and linear velocity of the wheelchair during the turning portions of propulsion. Using an instrumented handrim, velocity and push force data were recorded for 25 subjects while they propel their own wheelchairs on a concrete floor along a figure-eight-shaped course at a maximum velocity. The braking force (1.03 N) of the inside wheel while turning was the largest of all other push forces (p<0.05). Larger changes in squared velocity while turning were significantly correlated with higher propulsive and braking forces used at the pre-turning, turning, and post-turning phases (p<0.05). Subjects with less change of velocity while turning needed less braking force to maneuver themselves successfully and safely around the turns. Considering the magnitude and direction of tangential force applied to the wheel, it seems that there are higher risks of injury and instability for upper limb joints when braking the inside wheel to turn. The results provide insight into wheelchair setup and mobility skills training for wheelchair users.

Non-conventional optomechanical choppers: analysis and design of novel prototypes

NASA Astrophysics Data System (ADS)

Duma, Virgil-Florin; Demian, Dorin; Csukas, Eduard Sebastian; Pop, Nicolina; Cira, Octavian

2017-10-01

Optical choppers are widely used in laser systems - for light modulation and/or attenuation. In their most used and wellknown configuration, they are built as a rotational wheel with windows, which transforms a continuous-wave laser beam into a series of impulses with a certain frequency and profile. We briefly present the analysis and design we have completed for the classical chopper wheels (i.e., with windows with linear margins) for both top-hat and Gaussian laser beams. Further on, novel chopper wheels configurations, with outward or inward semi-circular (or with other non-linear shaped) margins of the windows is pointed out; we completed for them both analytic functions and simulations, for both top-hat and Gaussian beams, in order to deduce their transmission functions (i.e., the time profile of the laser impulses generated by the device). The stress of the presentation is put on the novel choppers with shafts (patent pending); their transmission functions are pointed out for top-hat laser beams. Finally, an example of such choppers is considered, with regard to the necessary Finite Element Analysis (FEA) that has to be performed for their rotational shaft. Both the mechanical stress and the deformations in the shaft have to be taken into account, especially at high rotational speeds of the mobile element.

A Self-Propelled Wheel for Wheeled Vehicles.

DTIC Science & Technology

1996-09-05

embodiments of both types, in 16 general the axial permanent magnet motors feature a stator disk, 17 or drum, with a central opening and electrical...6 In general, in radial permanent magnet motors , the stator is 7 annularly-shaped and is concentrically disposed around a 8 generally cylindrically...is to provide a motor 6 assembly which is more efficient than the presently available 7 axial permanent magnet motors and radial permanent magnet motors 8

The Need for a Shear Stress Calibration Standard

NASA Technical Reports Server (NTRS)

Scott, Michael A.

2004-01-01

By surveying current research of various micro-electro mechanical systems (MEMS) shear stress sensor development efforts we illustrate the wide variety of methods used to test and characterize these sensors. The different methods of testing these sensors make comparison of results difficult in some cases, and also this comparison is further complicated by the different formats used in reporting the results of these tests. The fact that making these comparisons can be so difficult at times clearly illustrates a need for standardized testing and reporting methodologies. This need indicates that the development of a national or international standard for the calibration of MEMS shear stress sensors should be undertaken. As a first step towards the development of this standard, two types of devices are compared and contrasted. The first type device is a laminar flow channel with two different versions considered: the first built with standard manufacturing techniques and the second with advanced precision manufacturing techniques. The second type of device is a new concept for creating a known shear stress consisting of a rotating wheel with the sensor mounted tangentially to the rim and positioned in close proximity to the rim. The shear stress generated by the flow at the sensor position is simply tau = (mu)r(omega)/h, where mu is the viscosity of the ambient gas, r the wheel radius, omega the angular velocity of the wheel, and h the width of the gap between the wheel rim and the sensor. Additionally, issues related to the development of a standard for shear stress calibration are identified and discussed.

Instrumented gait analysis: a measure of gait improvement by a wheeled walker in hospitalized geriatric patients.

PubMed

Schülein, Samuel; Barth, Jens; Rampp, Alexander; Rupprecht, Roland; Eskofier, Björn M; Winkler, Jürgen; Gaßmann, Karl-Günter; Klucken, Jochen

2017-02-27

In an increasing aging society, reduced mobility is one of the most important factors limiting activities of daily living and overall quality of life. The ability to walk independently contributes to the mobility, but is increasingly restricted by numerous diseases that impair gait and balance. The aim of this cross-sectional observation study was to examine whether spatio-temporal gait parameters derived from mobile instrumented gait analysis can be used to measure the gait stabilizing effects of a wheeled walker (WW) and whether these gait parameters may serve as surrogate marker in hospitalized patients with multifactorial gait and balance impairment. One hundred six patients (ages 68-95) wearing inertial sensor equipped shoes passed an instrumented walkway with and without gait support from a WW. The walkway assessed the risk of falling associated gait parameters velocity, swing time, stride length, stride time- and double support time variability. Inertial sensor-equipped shoes measured heel strike and toe off angles, and foot clearance. The use of a WW improved the risk of spatio-temporal parameters velocity, swing time, stride length and the sagittal plane associated parameters heel strike and toe off angles in all patients. First-time users (FTUs) showed similar gait parameter improvement patterns as frequent WW users (FUs). However, FUs with higher levels of gait impairment improved more in velocity, stride length and toe off angle compared to the FTUs. The impact of a WW can be quantified objectively by instrumented gait assessment. Thus, objective gait parameters may serve as surrogate markers for the use of walking aids in patients with gait and balance impairments.

Real-Time Identification of Wheel Terrain Interaction Models for Enhanced Autonomous Vehicle Mobility

DTIC Science & Technology

2014-04-24

tim at io n Er ro r ( cm ) 0 2 4 6 8 10 Color Statistics Angelova...Color_Statistics_Error) / Average_Slip_Error Position Estimation Error: Global Pose Po si tio n Es tim at io n Er ro r ( cm ) 0 2 4 6 8 10 12 Color...get some kind of clearance for releasing pose and odometry data) collected at the following sites – Taylor, Gascola, Somerset, Fort Bliss and

Structural Health Monitoring of M1114 High Mobility Multipurpose Wheeled Vehicle Armor System

DTIC Science & Technology

2012-03-01

compressional waves or compression waves (Russell, 1999). Pulse Echo Pulse echo method uses the transducer to perform both the sending and the...monolithic system of pure steel will not be sufficient because it would become too heavy and compromise its maneuverability and nimbleness. In order to...produce a limited number of M1114’s with hardened steel armor with bullet-resistant glass for the passenger cabinet against small arms fire. Even with its

Retrospective review of adverse incidents involving passengers seated in wheeled mobility devices while traveling in large accessible transit vehicles.

PubMed

Frost, Karen L; Bertocci, Gina

2010-04-01

Characterize wheeled mobility device (WhMD) adverse incidents on large accessible transit vehicles (LATVs) based on vehicle motion, WhMD activity during incident, incident scenario and injury. Retrospective records review. WhMD passengers traveling on LATVs while remaining seated in their. Adverse incidents characterized based on vehicle motion, WhMD activity during incident, and incident scenario. Injury characterized based on outcome, medical attention sought, vehicle activity, WhMD activity and incident scenario. 115 WhMD-related incident reports for years 2000-2005 were analyzed. Most incidents occurred when the LATV was stopped (73.9%), during ingress/egress (42.6%), and at the securement station (33.9%) when the LATV was moving. The combination of WhMD tipping and passenger falling (43.4%) occurred most frequently, and was 1.8 times more likely to occur during ingress/egress than at the securement station. One-third (33.6%) of all incidents resulted in injury, and injuries were equally distributed between ingress/egress (43.6%) and at the securement station (43.6%). WhMD users have a greater chance of incurring injury during ingress/egress than during transit. Research is needed to objectively assess real world transportation experiences of WhMD passengers, and to assess the adequacy of existing federal legislation/guidelines for accessible ramps used in public transportation. Copyright 2009 IPEM. Published by Elsevier Ltd. All rights reserved.

Resolved motion rate and resolved acceleration servo-control of wheeled mobile robots

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

Muir, P.F.; Neuman, C.P.; Carnegie-Mellon Univ., Pittsburgh, PA

1989-01-01

Accurate motion control of wheeled mobile robots (WMRs) is required for their application to autonomous, semi-autonomous and teleoperated tasks. The similarities between WMRs and stationary manipulators suggest that current, successful, model-based manipulator control algorithms may be applied to WMRs. Special characteristics of WMRs including higher-pairs, closed-chains, friction and unactuated and unsensed joints require innovative modeling methodologies. The WMR modeling challenge has been recently overcome, thus enabling the application of manipulator control algorithms to WMRs. This realization lays the foundation for significant technology transfer from manipulator control to WMR control. We apply two Cartesian-space manipulator control algorithms: resolved motion rate (kinematics-based)more » and resolved acceleration (dynamics-based) control to WMR servo-control. We evaluate simulation studies of two exemplary WMRs: Uranus (a three degree-of-freedom WMR constructed at Carnegie Mellon University), and Bicsun-Bicas (a two degree-of-freedom WMR being constructed at Sandia National Laboratories) under the control of these algorithms. Although resolved motion rate servo-control is adequate for the control of Uranus, resolved acceleration servo-control is required for the control of the mechanically simpler Bicsun-Bicas because it exhibits more dynamic coupling and nonlinearities. Successful accurate motion control of these WMRs in simulation is driving current experimental research studies. 18 refs., 7 figs., 5 tabs.« less

A development of intelligent entertainment robot for home life

NASA Astrophysics Data System (ADS)

Kim, Cheoltaek; Lee, Ju-Jang

2005-12-01

The purpose of this paper was to present the study and design idea for entertainment robot with educational purpose (IRFEE). The robot has been designed for home life considering dependability and interaction. The developed robot has three objectives - 1. Develop autonomous robot, 2. Design robot considering mobility and robustness, 3. Develop robot interface and software considering entertainment and education functionalities. The autonomous navigation was implemented by active vision based SLAM and modified EPF algorithm. The two differential wheels, the pan-tilt were designed mobility and robustness and the exterior was designed considering esthetic element and minimizing interference. The speech and tracking algorithm provided the good interface with human. The image transfer and Internet site connection is needed for service of remote connection and educational purpose.

Design and development of split-parallel through-the road retrofit hybrid electric vehicle with in-wheel motors

NASA Astrophysics Data System (ADS)

Zulkifli, S. A.; Syaifuddin Mohd, M.; Maharun, M.; Bakar, N. S. A.; Idris, S.; Samsudin, S. H.; Firmansyah; Adz, J. J.; Misbahulmunir, M.; Abidin, E. Z. Z.; Syafiq Mohd, M.; Saad, N.; Aziz, A. R. A.

2015-12-01

One configuration of the hybrid electric vehicle (HEV) is the split-axle parallel hybrid, in which an internal combustion engine (ICE) and an electric motor provide propulsion power to different axles. A particular sub-type of the split-parallel hybrid does not have the electric motor installed on board the vehicle; instead, two electric motors are placed in the hubs of the non-driven wheels, called ‘hub motor’ or ‘in-wheel motor’ (IWM). Since propulsion power from the ICE and IWM is coupled through the vehicle itself, its wheels and the road on which it moves, this particular configuration is termed ‘through-the-road’ (TTR) hybrid. TTR configuration enables existing ICE-powered vehicles to be retrofitted into an HEV with minimal physical modification. This work describes design of a retrofit- conversion TTR-IWM hybrid vehicle - its sub-systems and development work. Operating modes and power flow of the TTR hybrid, its torque coupling and resultant traction profiles are initially discussed.

Distinct motor impairments of dopamine D1 and D2 receptor knockout mice revealed by three types of motor behavior

PubMed Central

Nakamura, Toru; Sato, Asako; Kitsukawa, Takashi; Momiyama, Toshihiko; Yamamori, Tetsuo; Sasaoka, Toshikuni

2014-01-01

Both D1R and D2R knock out (KO) mice of the major dopamine receptors show significant motor impairments. However, there are some discrepant reports, which may be due to the differences in genetic background and experimental procedures. In addition, only few studies directly compared the motor performance of D1R and D2R KO mice. In this paper, we examined the behavioral difference among N10 congenic D1R and D2R KO, and wild type (WT) mice. First, we examined spontaneous motor activity in the home cage environment for consecutive 5 days. Second, we examined motor performance using the rota-rod task, a standard motor task in rodents. Third, we examined motor ability with the Step-Wheel task in which mice were trained to run in a motor-driven turning wheel adjusting their steps on foothold pegs to drink water. The results showed clear differences among the mice of three genotypes in three different types of behavior. In monitoring spontaneous motor activities, D1R and D2R KO mice showed higher and lower 24 h activities, respectively, than WT mice. In the rota-rod tasks, at a low speed, D1R KO mice showed poor performance but later improved, whereas D2R KO mice showed a good performance at early days without further improvement. When first subjected to a high speed task, the D2R KO mice showed poorer rota-rod performance at a low speed than the D1R KO mice. In the Step-Wheel task, across daily sessions, D2R KO mice increased the duration that mice run sufficiently close to the spout to drink water, and decreased time to touch the floor due to missing the peg steps and number of times the wheel was stopped, which performance was much better than that of D1R KO mice. These incongruent results between the two tasks for D1R and D2R KO mice may be due to the differences in the motivation for the rota-rod and Step-Wheel tasks, aversion- and reward-driven, respectively. The Step-Wheel system may become a useful tool for assessing the motor ability of WT and mutant mice. PMID:25076876

Distinct motor impairments of dopamine D1 and D2 receptor knockout mice revealed by three types of motor behavior.

PubMed

Nakamura, Toru; Sato, Asako; Kitsukawa, Takashi; Momiyama, Toshihiko; Yamamori, Tetsuo; Sasaoka, Toshikuni

2014-01-01

Both D1R and D2R knock out (KO) mice of the major dopamine receptors show significant motor impairments. However, there are some discrepant reports, which may be due to the differences in genetic background and experimental procedures. In addition, only few studies directly compared the motor performance of D1R and D2R KO mice. In this paper, we examined the behavioral difference among N10 congenic D1R and D2R KO, and wild type (WT) mice. First, we examined spontaneous motor activity in the home cage environment for consecutive 5 days. Second, we examined motor performance using the rota-rod task, a standard motor task in rodents. Third, we examined motor ability with the Step-Wheel task in which mice were trained to run in a motor-driven turning wheel adjusting their steps on foothold pegs to drink water. The results showed clear differences among the mice of three genotypes in three different types of behavior. In monitoring spontaneous motor activities, D1R and D2R KO mice showed higher and lower 24 h activities, respectively, than WT mice. In the rota-rod tasks, at a low speed, D1R KO mice showed poor performance but later improved, whereas D2R KO mice showed a good performance at early days without further improvement. When first subjected to a high speed task, the D2R KO mice showed poorer rota-rod performance at a low speed than the D1R KO mice. In the Step-Wheel task, across daily sessions, D2R KO mice increased the duration that mice run sufficiently close to the spout to drink water, and decreased time to touch the floor due to missing the peg steps and number of times the wheel was stopped, which performance was much better than that of D1R KO mice. These incongruent results between the two tasks for D1R and D2R KO mice may be due to the differences in the motivation for the rota-rod and Step-Wheel tasks, aversion- and reward-driven, respectively. The Step-Wheel system may become a useful tool for assessing the motor ability of WT and mutant mice.

Implications of Mobility Impairment on the Diagnosis and Treatment of Breast Cancer

PubMed Central

Park, Elyse R.; Kilbridge, Kerry L.

2011-01-01

Abstract Background Among women with chronic, preexisting mobility impairments, we sought to explore how their mobility difficulties affected the diagnosis and treatment of early-stage breast cancer Methods This is a qualitative analysis of transcripts from in-depth in-person or telephone interviews with 20 English-speaking women who had early-stage breast cancer, were <60 years of age, and had chronic difficulty walking or used wheeled mobility aids at the time of their breast cancer diagnoses Results Nine women were disabled by polio as children or had postpolio syndrome, 3 had cerebral palsy, 3 had spinal cord injury, and 5 had other conditions. Most women reported difficulty obtaining mammograms, primarily because of inaccessible equipment, positioning problems, and difficulties with uncontrollable movements. Many women made decisions about surgical approach and chemotherapy by explicitly considering how various therapies would affect their arms, which are essential to their mobility (they use ambulation aids, self-propel manual wheelchairs, or otherwise rely on their arms for mobility or safety). Managing at home after surgery posed major mobility challenges, especially for women who lived alone. Several women reported feeling they suffered more chemotherapy side effects than do women without mobility problems. Weight gains with endocrine therapy compromised the mobility of several women. Conclusions Increasing numbers of American women are living with mobility disabilities and entering age ranges with increased risks of breast cancer. Mobility impairments can affect women at every point during early-stage breast cancer diagnosis, therapy, and recovery. Clinicians must consider women's mobility functioning in making therapeutic recommendations to women with impaired mobility who develop breast cancer. PMID:21034276

Development of mobile sensor for volcanic observation "HOMURA": Test campaign at Kirishima Iwo-yama, SW Japan

NASA Astrophysics Data System (ADS)

Kaneko, K.; Ito, K.; Iwahori, K.; Anbe, Y.

2015-12-01

Monitoring volcanoes near active craters is important to know symptoms and transitions of volcanic eruptions. In order to observe volcanic phenomena near craters according to the circumstance, monitoring system with unmanned robots are useful. We have been trying to develop a practical UGV-type robot, and have completed a prototype, which we named "Homura". Homura is a small-sized, vehicle-type robot with six wheels (750 x 430 x 310 mm in dimensions and a weight of about 12 kg). Homura is remotely controlled with mobile phone radio waves; it can move in volcanic fields and send real time data of sensors equipped in the vehicle to the base station. We carried out a test campaign of Homura from Feb. 19th to Apr. 8th, 2015 at Iwo-yama to examine if Homura can work for a few month in natural volcanic fields. Iwo-yama is one of craters in the Kirishima volcanic field, SW Japan; the area within 1 km from the crater was an off-limit area from Oct. 24th, 2014 to May 5th, 2015 because volcanic seismicity there was active and eruption might occur. On Feb. 19th, we carried and put Homura at the rim of the crater. Unfortunately, mobile phone connectivity was not entirely stable around Iwo-yama. Then, we decided not to move Homura and only to obtain real time data of the sensors (a camera, CO2 gas sensor, and thermometer). After we returned to our office, we operated Homura for one to two hours every day until Apr. 8th. Although the weather was often bad (rain, fog, or cold temperature) during the test campaign, we could completely operate Homura without any trouble. On Apr. 8th, the battery in Homura ran down. After we collected Homura from Iwo-yama and recharged the battery, Homura perfectly worked again. The results of this campaign indicate that Homura stably operates for a long time in volcanic field. Homura is useful as simple monitoring station in volcanic fields where mobile phone connection is available.

36. INTERIOR VIEW, NORTON GRINDER, TYPES USED TO GRIND ROUGH ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

36. INTERIOR VIEW, NORTON GRINDER, TYPE-S USED TO GRIND ROUGH EDGES OFF THE FORGED TOOLS; NOTE OPERATOR IS FINISH GRINDING BLADE END OF A POST HOLE DIGGER AND TAMPING BAR - Warwood Tool Company, Foot of Nineteenth Street, Wheeling, Ohio County, WV

Flexible Manufacturing System Handbook. Volume II. Description of the Technology

DTIC Science & Technology

1983-02-01

hubs, or wheels with considerable 4 FM5 Handbook, Volume II milling, drilling and/or tapping, are usually candidates for inclusion in a prismatic...0.06 inch) to transfer pallets to a machine or unload station. Wheel encoders can be used as less precise feedback for the drive system and its...must be used to control pallet transfer. The Cincinnati Milacron Variable Mission System uses this type of MHS, specifically the Eaton-Kenway Robo

Differential sensitivity of Pak5, Pak6, and Pak5/Pak6 double-knockout mice to the stimulant effects of amphetamine and exercise-induced alterations in body weight.

PubMed

Furnari, Melody A; Jobes, Michelle L; Nekrasova, Tanya; Minden, Audrey; Wagner, George C

2014-04-01

PAK5 and PAK6 are protein kinases highly expressed in the brain. Previously, we observed that Pak6 knockout mice gained significantly more weight during development than Pak5 knockout mice as well as wild-type controls and double-knockout mice lacking both Pak5 and Pak6. In this study, we assessed the effects of exercise on food intake and weight gain of these mice as well as their sensitivity to the stimulant effects of amphetamine. Mice of each genotype were placed in cages with free access to run wheel exercise or in cages without run wheels for a total of 74 days. Food and fluid intake as well as body weight of each mouse were measured on a weekly basis. Finally, mice were given a high dose of amphetamine and activity levels were observed immediately thereafter for 90 minutes. Brains and testes of mice were assayed for protein levels of the estrogen alpha and progesterone receptors. While run wheel mice consumed significantly more food, they weighed less than non-run wheel mice. In addition, although Pak6 knockout mice consumed the same amount of food as wild-type mice, they were significantly heavier regardless of run wheel condition. Pak5 knockout mice were found to be more active than other genotypes after amphetamine treatment. Finally, protein levels of the progesterone and estrogen alpha receptors were altered in brain and testes of the Pak6 knockout mice. Collectively, these data suggest that PAK6 play a role in weight gain unrelated to exercise and caloric intake and that Pak5 knockout mice are more sensitive to the stimulant effects of amphetamine.

Community reintegration and related factors in a Nigerian stroke sample.

PubMed

Akosile, Christopher; Nworah, Chioma; Okoye, Emmanuel; Adegoke, Babatunde; Umunnah, Joseph; Fabunmi, Ayodeji

2016-09-01

The goal of stroke rehabilitation has shifted from mere survival of a victim to how well a survivor can be effectively reintegrated back into the community. The present study determined the level of satisfaction with community reintegration (CR) and related factors among Nigerian community-dwelling stroke survivors (CDSS). This was a cross-sectional survey of 71 volunteering CDSS (35 males, 36 females) from selected South-Eastern Nigerian communities. Reintegration to Normal Living Index was used to assess participants' CR. Data was analysed using Spearman rank-order correlation, Kruskal-Wallis and Mann-Whitney U tests at p≤0.05. Participants generally had deficits in CR which was either mild/moderate (52.1%) or severe (47.9%). Scores in the CR domains of distance mobility, performance of daily activities, recreational activities and family roles were particularly low (median scores ≤ 4). CR was significantly correlated with and influenced by age (r=-0.35; p=0.00) and presence/absence of diabetes mellitus (u=3.56.50; p=0.01), pre- (k=6.13; p=0.05) and post-stroke employment (k=18.26; p=0.00) status, type of assistive mobility device being used (AMD) (k=25.39; p=0.00) and support from the community (k=7.15; p=0.03) respectively. CR was generally poor for this CDSS sample. Survivors who are older, having diabetes as co-morbidity, using AMD (particularly wheel-chair) and without employment pre- and/or post-stroke may require keener attention. Rehabilitation focus may be targeted at enhancing mobility functions, vocational and social skills.

XRF and micro-PIXE studies of inhomogeneity of ancient bronze and silver alloys

NASA Astrophysics Data System (ADS)

Vasilescu, A.; Constantinescu, B.; Stan, D.; Talmatchi, G.; Ceccato, D.

2017-09-01

New results regarding alloy composition and microstructure for a series of ancient bronze and silver items by X-ray Fluorescence and micro-Particle Induced X-ray Emission spectrometry were obtained in the framework of an extensive numismatic project (Scythian-type arrowheads, arrowhead-shaped monetary signs and wheel coins produced by Histria, 7th-4th century of BCE, and Dacian Radulesti-Hunedoara-type silver tetradrachms, 2nd-1st century of BCE). In Histria, warfare arrowheads were used for trade with Barbarian neighbors at first, then mechanically modified, next melted and cast as dedicated monetary signs, being, in the end, replaced by wheel coins. Three different types of alloys have been identified, and Cu-Mn and Cu-Pb segregation shown. In a blank for Radulesti-Hunedoara-type coins, Ag-(Cu+Pb) segregation has been demonstrated, suggesting an imperfectly alloyed silver-leaded bronze.

Structural safety of trams in case of misguidance in a switch

NASA Astrophysics Data System (ADS)

Schindler, Christian; Schwickert, Martin; Simonis, Andreas

2010-08-01

Tram vehicles mainly operate on street tracks where sometimes misguidance in switches occurs due to unfavourable conditions. Generally, in this situation, the first running gear of the vehicle follows the bend track while the next running gears continue straight ahead. This leads to a constraint that can only be solved if the vehicle's articulation is damaged or the wheel derails. The last-mentioned situation is less critical in terms of safety and costs. Five different tram types, one of them high floor, the rest low floor, were examined analytically. Numerical simulation was used to determine which wheel would be the first to derail and what level of force is needed in the articulation area between two carbodies to make a tram derail. It was shown that with pure analytical simulation, only an idea of which tram type behaves better or worse in such a situation can be gained, while a three-dimensional computational simulation gives more realistic values for the forces that arise. Three of the four low-floor tram types need much higher articulation forces to make a wheel derail in a switch misguidance situation. One particular three-car type with two single-axle running gears underneath the centre car must be designed to withstand nearly three times higher articulation forces than a conventional high-floor articulated tram. Tram designers must be aware of that and should design the carbody accordingly.

Development of crawler type device using new measuring system

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

Maruyama, T.; Sasaki, T.; Yagi, T.

1995-08-01

This paper reports the development and field application of a new device which examine shell to shell weld joints of RPV. In a BWR type nuclear power plant, there is narrow space around the Reactor Pressure Vessel (RPV) because RPV is enclosed by the Reactor Shield Wall (RSW) and thermal insulations. The developed device is characterized by a new position measuring system and magnet wheels for driving. The new position measuring system uses laser beam and ultrasonic wave. The magnet wheels make the device travel freely in the narrow space between RPV and insulation. This device is tested on mock-upsmore » and applied examination of RPVs to verify field applicability.« less

Mobile and stationary laser weapon demonstrators of Rheinmetall Waffe Munition

NASA Astrophysics Data System (ADS)

Ludewigt, K.; Riesbeck, Th.; Baumgärtel, Th.; Schmitz, J.; Graf, A.; Jung, M.

2014-10-01

For some years Rheinmetall Waffe Munition has successfully developed, realised and tested a variety of versatile high energy laser (HEL) weapon systems for air- and ground-defence scenarios like C-RAM, UXO clearing. By employing beam superimposition technology and a modular laser weapon concept, the total optical power has been successively increased. Stationary weapon platforms and now military mobile vehicles were equipped with high energy laser effectors. Our contribution summarises the most recent development stages of Rheinmetalls high energy laser weapon program. We present three different vehicle based HEL demonstrators: the 5 kW class Mobile HEL Effector Track V integrated in an M113 tank, the 20 kW class Mobile HEL Effector Wheel XX integrated in a multirole armoured vehicle GTK Boxer 8x8 and the 50 kW class Mobile HEL Effector Container L integrated in a reinforced container carried by an 8x8 truck. As a highlight, a stationary 30 kW Laser Weapon Demonstrator shows the capability to defeat saturated attacks of RAM targets and unmanned aerial vehicles. 2013 all HEL demonstrators were tested in a firing campaign at the Rheinmetall testing centre in Switzerland. Major results of these tests are presented.

Transforming Roving-Rolling Explorer (TRREx) for Planetary Exploration

NASA Astrophysics Data System (ADS)

Edwin, Lionel Ernest

All planetary surface exploration missions thus far have employed traditional rovers with a rocker-bogie suspension. These rovers can navigate moderately rough and flat terrain, but are not designed to traverse rugged terrain with steep slopes. The fact is, however, that many scientifically interesting missions require exploration platforms with capabilities for navigating such types of chaotic terrain. This issue motivates the development of new kinds of rovers that take advantage of the latest advances in robotic technologies to traverse rugged terrain efficiently. This dissertation proposes and analyses one such rover concept called the Transforming Roving-Rolling Explorer (TRREx) that is principally aimed at addressing the above issue. Biologically inspired by the way the armadillo curls up into a ball when threatened, and the way the golden wheel spider uses the dynamic advantages of a sphere to roll down hills when escaping danger, the novel TRREx rover can traverse like a traditional 6-wheeled rover over conventional terrain, but can also transform itself into a sphere, when necessary, to travel down steep inclines, or navigate rough terrain. This work presents the proposed design architecture and capabilities followed by the development of mathematical models and experiments that facilitate the mobility analysis of the TRREx in the rolling mode. The ability of the rover to self-propel in the rolling mode in the absence of a negative gradient increases its versatility and concept value. Therefore, a dynamic model of a planar version of the problem is first used to investigate the feasibility and value of such self-propelled locomotion - 'actuated rolling'. Construction and testing of a prototype Planar/Cylindrical TRREx that is capable of demonstrating actuated rolling is presented, and the results from the planar dynamic model are experimentally validated. This planar model is then built upon to develop a mathematical model of the spherical TRREx in the rolling mode, i.e. when the rover is a sphere and can steer itself through actuations that shift its center of mass to achieve the desired direction of roll. Case studies that demonstrate the capabilities of the rover in rolling mode and parametric analyses that investigate the dependence of the rover's mobility on its design are presented. This work highlights the contribution of the spherical rolling mode to the enhanced mobility of the TRREx rover and how it could enable challenging surface exploration missions in the future. It represents an important step toward developing a rover capable of traversing a variety of terrains that are impassible by the current fleet of rover designs, and thus has the potential to revolutionize planetary surface exploration.

Improvements Needed on DoD Procurements from Robertson Fuel Systems (REDACTED)

DTIC Science & Technology

2015-06-25

reasonable price, but is not certified. 4 A ballistically self-sealing tank is designed to prevent fuel loss and a fire after damage. FOR OFFICIAL USE ONLY...pubs/index.cfm. DoD IG DODIG-2015-120, “Defense Logistics Agency Did Not Obtain Fair and Reasonable Prices from Meggitt Aircraft Braking System for...Mobility Multipurpose Wheeled Vehicle Repair Parts,” April 4, 2014 DODIG-2014-020, “U.S. Army Contracting Command Did Not Obtain Fair and Reasonable

A Combinatorial Geometry Target Description of the High Mobility Multipurpose Wheeled Vehicle (HMMWV)

DTIC Science & Technology

1985-10-01

NOTE3 1W. KFY OORDS (Continwo =n reverse aide If necesesar aid ldwttlfy by" block ntmber) •JW7 Regions, COM-EOM Region Ident• fication GIFT Material...technique of mobna.tcri• i Geometr- (Com-Geom). The Com-Gem data is used as input to the Geometric Inf• •cation for Targets ( GIFT ) computer code to... GIFT ) 2 3 computer code. This report documents the combinatorial geometry (Com-Geom) target description data which is the input data for the GIFT code

Microsensors and Microinstruments for Space Science and Exploration

NASA Technical Reports Server (NTRS)

Kukkonen, C. A.; Venneri, S.

1997-01-01

Most future NASA spacecraft will be small, low cost, highly integrated vehicles using advanced technology. This will also be true of planetary rovers. In order to maintain a high scientific value to these missions, the instruments, sensors and subsystems must be dramatically miniaturized without compromising their measurement capabilities. A rover must be designed to deliver its science package. In fact, the rover should be considered as the arms, legs and/or wheels that are needed to enable a mobile integrated scientific payload.

Performance Analysis and Odometry Improvement of an Omnidirectional Mobile Robot for Outdoor Terrain

DTIC Science & Technology

2011-09-01

sin cos , , =      +=         = iD v v i i b yi xi i ξ ξ φ xx (1) where ix and bx are the planer velocity vectors at the i-th...variables given by an operator. The wheel angular velocities, ωi,L and ωi,R, that yield the desired i-th ASOC planer velocity are formulated as follows

Mars Science Laboratory Rover Mobility Bushing Development

NASA Technical Reports Server (NTRS)

Riggs, Benjamin

2008-01-01

NASA s Mars Science Laboratory (MSL) Project will send a six-wheeled rover to Mars in 2009. The rover will carry a scientific payload designed to search for organic molecules on the Martian surface during its primary mission. This paper describes the development and testing of a bonded film lubricated bushing system to be used in the mobility system of the rover. The MSL Rover Mobility System contains several pivots that are tightly constrained with respect to mass and volume. These pivots are also exposed to relatively low temperatures (-135 C) during operation. The combination of these constraints led the mobility team to consider the use of solid film lubricated metallic bushings and dry running polymeric bushings in several flight pivot applications. A test program was developed to mitigate the risk associated with using these materials in critical pivots on the MSL vehicle. The program was designed to characterize bushing friction and wear performance over the expected operational temperature range (-135 C to +70 C). Seven different bushing material / lubricant combinations were evaluated to aid in the selection of the final flight pivot bushing material / lubricant combination.

A Study on an Analysis and Design of the Internal Structure of Heumgyeonggak-nu

NASA Astrophysics Data System (ADS)

Kim, Sang Hyuk; Yun, Yong-Hyun; Ham, Seon Young; Mihn, Byeong-Hee; Ki, Ho-Chul; Yoon, Myung-Kyoon

2017-06-01

In this study, the internal structure of a Heumgyeonggak-nu (欽敬閣漏) was designed, and the power transmission mechanism was analyzed. Heumgyeonggak-nu is an automated water clock from the Joseon Dynasty that was installed within Heumgyeonggak (欽敬閣), and it was manufactured in the 20th year of the reign of King Sejong (1438). As descriptions of Heumgyeonggak-nu in ancient literature have mostly focused on its external shape, the study of its internal mechanism has been difficult. A detailed analysis of the literature record on Heumgyeonggak-nu (e.g., The Annals of the Joseon Dynasty) indicates that Heumgyeonggaknu had a three-stage water clock, included a waterfall or tilting vessel (欹器) using the overflowed water, and displayed the time using a ball. In this study, the Cheonhyeong apparatus, water wheel, scoop, and various mechanism wheels were designed so that 16 fixed-type scoops could operate at a constant speed for the water wheel with a diameter of 100 cm. As the scoop can contain 1.25 l of water and the water wheel rotates 61 times a day, a total of 1,220 l of water is required. Also, the power gear wheel was designed as a 366-tooth gear, which supported the operation of the time signal gear wheel. To implement the movement of stars on the celestial sphere, the rotation ratio of the celestial gear wheel to the diurnal motion gear ring was set to 366:365. In addition, to operate the sun movement apparatus on the ecliptic, a gear device was installed on the South Pole axis. It is expected that the results of this study can be used for the manufacture and restoration of the operation model of Heumgyeonggak-nu.

Extremity fractures associated with ATVs and dirt bikes: a 10-year national epidemiologic study.

PubMed

Lombardo, D J; Jelsema, T; Gambone, A; Weisman, M; Petersen-Fitts, G; Whaley, J D; Sabesan, V J

2017-08-01

Morbidity and mortality of all-terrain vehicles and dirt bikes have been studied, as well as the association of helmet use and head injury. The purpose of this study is to compare and contrast the patterns of extremity fractures associated with ATVs and dirt bikes. We believe there will be unique and potentially preventable injury patterns associated with dirt bikes and three-wheeled ATVs due to the poor stability of these vehicles. Descriptive epidemiology study. The National Electronic Injury Surveillance System (NEISS) was used to acquire data for extremity fractures related to ATV (three wheels, four wheels, and number of wheels undefined) and dirt bike use from 2007 to 2012. Nationwide estimation of injury incidence was determined using NEISS weight calculations. The database yielded an estimate of 229,362 extremity fractures from 2007 to 2012. The incidence rates of extremity fractures associated with ATV and dirt bike use were 3.87 and 6.85 per 1000 participant-years. The largest proportion of all fractures occurred in the shoulder (27.2%), followed by the wrist and lower leg (13.8 and 12.4%, respectively). There were no differences in the distribution of the location of fractures among four-wheeled or unspecified ATVs. However, three-wheeled ATVs and dirt bikes had much larger proportion of lower leg, foot, and ankle fractures compared to the other vehicle types. While upper extremity fractures were the most commonly observed in this database, three-wheeled ATVs and dirt bikes showed increased proportions of lower extremity fractures. Several organizations have previously advocated for better regulation of the sale and use of these specific vehicles due to increased risks. These findings help illustrate some of the specific risks associated with these commonly used vehicles.

Running promotes wakefulness and increases cataplexy in orexin knockout mice.

PubMed

España, Rodrigo A; McCormack, Sarah L; Mochizuki, Takatoshi; Scammell, Thomas E

2007-11-01

People with narcolepsy and mice lacking orexin/hypocretin have disrupted sleep/wake behavior and reduced physical activity. Our objective was to identify physiologic mechanisms through which orexin deficiency reduces locomotor activity. We examined spontaneous wheel running activity and its relationship to sleep/wake behavior in wild type (WT) and orexin knockout (KO) mice. Additionally, given that physical activity promotes alertness, we also studied whether orexin deficiency reduces the wake-promoting effects of exercise. Orexin KO mice ran 42% less than WT mice. Their ability to run appeared normal as they initiated running as often as WT mice and ran at normal speeds. However, their running bouts were considerably shorter, and they often had cataplexy or quick transitions into sleep after running. Wheel running increased the total amount of wakefulness in WT and orexin KO mice similarly, however, KO mice continued to have moderately fragmented sleep/wake behavior. Wheel running also doubled the amount of cataplexy by increasing the probability of transitioning into cataplexy. Orexin KO mice run significantly less than normal, likely due to sleepiness, imminent cataplexy, or a reduced motivation to run. Orexin is not required for the wake-promoting effects of wheel running given that both WT and KO mice had similar increases in wakefulness with running wheels. In addition, the clear increase in cataplexy with wheel running suggests the possibility that positive emotions or reward can trigger murine cataplexy, similar to that seen in people and dogs with narcolepsy.

Running wheel exercise reduces α-synuclein aggregation and improves motor and cognitive function in a transgenic mouse model of Parkinson's disease

PubMed Central

Barkow, Jessica Cummiskey; Freed, Curt R.

2017-01-01

Exercise has been recommended to improve motor function in Parkinson patients, but its value in altering progression of disease is unknown. In this study, we examined the neuroprotective effects of running wheel exercise in mice. In adult wild-type mice, one week of running wheel activity led to significantly increased DJ-1 protein concentrations in muscle and plasma. In DJ-1 knockout mice, running wheel performance was much slower and Rotarod performance was reduced, suggesting that DJ-1 protein is required for normal motor activity. To see if exercise can prevent abnormal protein deposition and behavioral decline in transgenic animals expressing a mutant human form of α-synuclein in all neurons, we set up running wheels in the cages of pre-symptomatic animals at 12 months old. Activity was monitored for a 3-month period. After 3 months, motor and cognitive performance on the Rotarod and Morris Water Maze were significantly better in running animals compared to control transgenic animals with locked running wheels. Biochemical analysis revealed that running mice had significantly higher DJ-1, Hsp70 and BDNF concentrations and had significantly less α-synuclein aggregation in brain compared to control mice. By contrast, plasma concentrations of α-synuclein were significantly higher in exercising mice compared to control mice. Our results suggest that exercise may slow the progression of Parkinson’s disease by preventing abnormal protein aggregation in brain. PMID:29272304

A dragline-forming mobile robot inspired by spiders.

PubMed

Wang, Liyu; Culha, Utku; Iida, Fumiya

2014-03-01

Mobility of wheeled or legged machines can be significantly increased if they are able to move from a solid surface into a three-dimensional space. Although that may be achieved by addition of flying mechanisms, the payload fraction will be the limiting factor in such hybrid mobile machines for many applications. Inspired by spiders producing draglines to assist locomotion, the paper proposes an alternative mobile technology where a robot achieves locomotion from a solid surface into a free space. The technology resembles the dragline production pathway in spiders to a technically feasible degree and enables robots to move with thermoplastic spinning of draglines. As an implementation, a mobile robot has been prototyped with thermoplastic adhesives as source material of the draglines. Experimental results show that a dragline diameter range of 1.17-5.27 mm was achievable by the 185 g mobile robot in descending locomotion from the solid surface of a hanging structure with a power consumption of 4.8 W and an average speed of 5.13 cm min(-1). With an open-loop controller consisting of sequences of discrete events, the robot has demonstrated repeatable dragline formation with a relative deviation within -4% and a length close to the metre scale.

Hand on the wheel, mind on the mobile: an analysis of social factors contributing to texting while driving.

PubMed

Seiler, Steven J

2015-02-01

In an era defined by social technology, mobile phones provide constant connection to others. However, they also present a very dangerous situation when people choose to use their mobile phones while driving. In particular, exchanging text messages while driving has resulted in numerous accidents and fatalities. The purpose of this study is to examine social factors that lead people to text while driving. Specifically, using a multivariate logistic regression analysis of data from a 2010 survey by the Pew Research Center, variables for general mobile talk, driving while talking on a mobile, using the Internet on a mobile, sexting, and various motivations for texting were examined to determine factors that increase the likelihood of texting while driving. The findings suggest that people engage in mobile multiplexing (i.e., communication using two or more media on the mobile) while driving. Additionally, exchanging text messages in public, and consequently texting while driving, has become normalized. Furthermore, people are socialized into such behaviors through observing others texting while driving and using a mobile recklessly while driving. Finally, a number of motivations for texting were found to increase the likelihood of texting while driving significantly. Ultimately, the author contends that texting while driving has become a cultural artifact in the United States, which conflicts with driver safety as well as laws prohibiting texting while driving. The findings of this study could inform future awareness campaigns and technology developers to help establish a safer driving environment within the multitasking culture.

Steering system for a train of rail-less vehicles

DOEpatents

Voight, Edward T.

1983-01-01

A steering system for use with a multiple vehicle train permits tracking without rails of one vehicle after another. This system is particularly useful for moving conveyor systems into and out of curved paths of room and pillar underground mine installations. The steering system features an elongated steering bar pivotally connected to each of adjacent vehicles at end portions of the bar permitting angular orientation of each vehicle in respect to the steering bar and other vehicles. Each end portion of the steering bar is linked to the near pair of vehicle wheels through wheel yoke pivot arms about king pin type pivots. Movement of the steering bar about its pivotal connection provides proportional turning of the wheels to effect steering and tracking of one vehicle following another in both forward and reverse directions.

Tire-to-Surface Friction Especially Under Wet Conditions

NASA Technical Reports Server (NTRS)

Sawyer, Richard H.; Batterson, Sidney A.; Harrin, Eziaslav N.

1959-01-01

The results of measurements of the maximum friction available in braking on various runway surfaces under various conditions is shown for a C-123B airplane and comparisons of measurements with a tire-friction cart on the same runways are made. The.results of studies of wet-surface friction made with a 12-inch-diameter low-pressure tire on a tire-friction treadmill, with an automobile tire on the tire-friction cart, and with a 44 x 13 extra-high-pressure type VII aircraft tire at the Langley landing-loads track are compared. Preliminary results of tests on the tire-friction treadmill under wet-surface conditions to determine the effect of the wiping action of the front wheel of a tandem-wheel arrangement on the friction available in braking for the rear wheel are given.

Effects of input device and motion type on a cursor-positioning task.

PubMed

Yau, Yi-Jan; Hwang, Sheue-Ling; Chao, Chin-Jung

2008-02-01

Many studies have investigated the performance of using nonkey-board input devices under static situations, but few have considered the effects of motion type on manipulating these input devices. In this study comparison of 12 mens' performance using four input devices (three trackballs: currently used, trackman wheel, and erectly held trackballs, as well as a touch screen) under five motion types of static, heave, roll, pitch, and random movements was conducted. The input device and motion type significantly affected movement speed and accuracy, and their interaction significantly affected the movement speed. The touch screen was the fastest but the least accurate input device. The erectly held trackball was the slowest, whereas the error rate of the currently used trackball was the lowest. Impairments of the random motion on movement time and error rate were larger than those of other motion types. Considering objective and subjective evaluations, the trackman wheel and currently used trackball were more efficient in operation than the erectly held trackball and touch screen under the motion environments.

Event-Based Control Strategy for Mobile Robots in Wireless Environments.

PubMed

Socas, Rafael; Dormido, Sebastián; Dormido, Raquel; Fabregas, Ernesto

2015-12-02

In this paper, a new event-based control strategy for mobile robots is presented. It has been designed to work in wireless environments where a centralized controller has to interchange information with the robots over an RF (radio frequency) interface. The event-based architectures have been developed for differential wheeled robots, although they can be applied to other kinds of robots in a simple way. The solution has been checked over classical navigation algorithms, like wall following and obstacle avoidance, using scenarios with a unique or multiple robots. A comparison between the proposed architectures and the classical discrete-time strategy is also carried out. The experimental results shows that the proposed solution has a higher efficiency in communication resource usage than the classical discrete-time strategy with the same accuracy.

Event-Based Control Strategy for Mobile Robots in Wireless Environments

PubMed Central

Socas, Rafael; Dormido, Sebastián; Dormido, Raquel; Fabregas, Ernesto

2015-01-01

In this paper, a new event-based control strategy for mobile robots is presented. It has been designed to work in wireless environments where a centralized controller has to interchange information with the robots over an RF (radio frequency) interface. The event-based architectures have been developed for differential wheeled robots, although they can be applied to other kinds of robots in a simple way. The solution has been checked over classical navigation algorithms, like wall following and obstacle avoidance, using scenarios with a unique or multiple robots. A comparison between the proposed architectures and the classical discrete-time strategy is also carried out. The experimental results shows that the proposed solution has a higher efficiency in communication resource usage than the classical discrete-time strategy with the same accuracy. PMID:26633412

Adaptive Trajectory Tracking of Nonholonomic Mobile Robots Using Vision-Based Position and Velocity Estimation.

PubMed

Li, Luyang; Liu, Yun-Hui; Jiang, Tianjiao; Wang, Kai; Fang, Mu

2018-02-01

Despite tremendous efforts made for years, trajectory tracking control (TC) of a nonholonomic mobile robot (NMR) without global positioning system remains an open problem. The major reason is the difficulty to localize the robot by using its onboard sensors only. In this paper, a newly designed adaptive trajectory TC method is proposed for the NMR without its position, orientation, and velocity measurements. The controller is designed on the basis of a novel algorithm to estimate position and velocity of the robot online from visual feedback of an omnidirectional camera. It is theoretically proved that the proposed algorithm yields the TC errors to asymptotically converge to zero. Real-world experiments are conducted on a wheeled NMR to validate the feasibility of the control system.

Voluntary scheduled exercise alters diurnal rhythms of behaviour, physiology and gene expression in wild-type and vasoactive intestinal peptide-deficient mice

PubMed Central

Schroeder, Analyne M; Truong, Danny; Loh, Dawn H; Jordan, Maria C; Roos, Kenneth P; Colwell, Christopher S

2012-01-01

The circadian system co-ordinates the temporal patterning of behaviour and many underlying biological processes. In some cases, the regulated outputs of the circadian system, such as activity, may be able to feed back to alter core clock processes. In our studies, we used four wheel-access conditions (no access; free access; early night; and late night) to manipulate the duration and timing of activity while under the influence of a light–dark cycle. In wild-type mice, scheduled wheel access was able to increase ambulatory activity, inducing a level of exercise driven at various phases of the light–dark cycle. Scheduled exercise also manipulated the magnitude and phasing of the circadian-regulated outputs of heart rate and body temperature. At a molecular level, the phasing and amplitude of PER2::LUCIFERASE (PER2::LUC) expression rhythms in the SCN and peripheral tissues of Per2::Luc knockin mice were altered by scheduled exercise. We then tested whether scheduled wheel access could improve deficits observed in vasointestinal polypeptide-deficient mice under the influence of a light–dark cycle. We found that scheduled wheel access during the late night improved many of the behavioural, physiological and molecular deficits previously described in vasointestinal polypeptide-deficient mice. Our results raise the possibility that scheduled exercise could be used as a tool to modulate daily rhythms and, when applied, may counteract some of the negative impacts of ageing and disease on the circadian system. PMID:22988135

Responding for sucrose and wheel-running reinforcement: effect of D-amphetamine.

PubMed

Belke, T W; Oldford, A C; Forgie, M Y; Beye, J A

2005-07-01

The present study assessed the effect of D-amphetamine on responding maintained by wheel-running and sucrose reinforcement. Six male albino Wistar rats were placed in running wheels and exposed to a fixed-interval 30-s schedule that produced either a drop of 5% sucrose solution or the opportunity to run for 15 s as reinforcing consequences for lever pressing. Each reinforcer type was signaled by a different stimulus. Doses of 0.25, 0.5, 1.0, 1.5, and 3.0 mg/kg D-amphetamine were administered by i.p. injection 20 min prior to a session. As the dose increased, index of curvature values decreased toward zero and rate-dependency plots revealed increases in lower rates early in the interval and decreases in higher rates toward the end of the interval. Effects were similar in the presence of both stimuli. However, an analysis of post-reinforcement pauses and local response rates broken down by transitions revealed a differential effect. As the dose increased, local response rates following a wheel-running reinforcer were affected more than those following a sucrose reinforcer.

Improving mobile robot localization: grid-based approach

NASA Astrophysics Data System (ADS)

Yan, Junchi

2012-02-01

Autonomous mobile robots have been widely studied not only as advanced facilities for industrial and daily life automation, but also as a testbed in robotics competitions for extending the frontier of current artificial intelligence. In many of such contests, the robot is supposed to navigate on the ground with a grid layout. Based on this observation, we present a localization error correction method by exploring the geometric feature of the tile patterns. On top of the classical inertia-based positioning, our approach employs three fiber-optic sensors that are assembled under the bottom of the robot, presenting an equilateral triangle layout. The sensor apparatus, together with the proposed supporting algorithm, are designed to detect a line's direction (vertical or horizontal) by monitoring the grid crossing events. As a result, the line coordinate information can be fused to rectify the cumulative localization deviation from inertia positioning. The proposed method is analyzed theoretically in terms of its error bound and also has been implemented and tested on a customary developed two-wheel autonomous mobile robot.

Mobility Systems For Robotic Vehicles

NASA Astrophysics Data System (ADS)

Chun, Wendell

1987-02-01

The majority of existing robotic systems can be decomposed into five distinct subsystems: locomotion, control/man-machine interface (MMI), sensors, power source, and manipulator. When designing robotic vehicles, there are two main requirements: first, to design for the environment and second, for the task. The environment can be correlated with known missions. This can be seen by analyzing existing mobile robots. Ground mobile systems are generally wheeled, tracked, or legged. More recently, underwater vehicles have gained greater attention. For example, Jason Jr. made history by surveying the sunken luxury liner, the Titanic. The next big surge of robotic vehicles will be in space. This will evolve as a result of NASA's commitment to the Space Station. The foreseeable robots will interface with current systems as well as standalone, free-flying systems. A space robotic vehicle is similar to its underwater counterpart with very few differences. Their commonality includes missions and degrees-of-freedom. The issues of stability and communication are inherent in both systems and environment.

A locust-inspired miniature jumping robot.

PubMed

Zaitsev, Valentin; Gvirsman, Omer; Ben Hanan, Uri; Weiss, Avi; Ayali, Amir; Kosa, Gabor

2015-11-25

Unmanned ground vehicles are mostly wheeled, tracked, or legged. These locomotion mechanisms have a limited ability to traverse rough terrain and obstacles that are higher than the robot's center of mass. In order to improve the mobility of small robots it is necessary to expand the variety of their motion gaits. Jumping is one of nature's solutions to the challenge of mobility in difficult terrain. The desert locust is the model for the presented bio-inspired design of a jumping mechanism for a small mobile robot. The basic mechanism is similar to that of the semilunar process in the hind legs of the locust, and is based on the cocking of a torsional spring by wrapping a tendon-like wire around the shaft of a miniature motor. In this study we present the jumping mechanism design, and the manufacturing and performance analysis of two demonstrator prototypes. The most advanced jumping robot demonstrator is power autonomous, weighs 23 gr, and is capable of jumping to a height of 3.35 m, covering a distance of 1.37 m.

Controllability of Complex Dynamic Objects

NASA Astrophysics Data System (ADS)

Kalach, G. G.; Kazachek, N. A.; Morozov, A. A.

2017-01-01

Quality requirements for mobile robots intended for both specialized and everyday use are increasing in step with the complexity of the technological tasks assigned to the robots. Whether a mobile robot is for ground, aerial, or underwater use, the relevant quality characteristics can be summarized under the common concept of agility. This term denotes the object’s (the robot)’s ability to react quickly to control actions (change speed and direction), turn in a limited area, etc. When using this approach in integrated assessment of the quality characteristics of an object with the control system, it seems more constructive to use the term “degree of control”. This paper assesses the degree of control by an example of a mobile robot with the variable-geometry drive wheel axle. We show changes in the degree of control depending on the robot’s configuration, and results illustrated by calculation data, computer and practical experiments. We describe the prospects of using intelligent technology for efficient control of objects with a high degree of controllability.

Using special additions to preparation of the moulding mixture for casting steel parts of drive wheel type

NASA Astrophysics Data System (ADS)

Josan, A.; Pinca Bretotean, C.

2015-06-01

The paper presents the possibility of using special additions to the execution of moulding mixtures for steel castings, drive wheel type. Critical analysis of moulding technology leads to the idea that most defects appear due to using improper moulding mixture. Using a improper moulding mixture leads to penetration of steel in moulding mixture, resulting in the formation of adherences, due to inadequate refractarity of the mould and core mixtures. Using only the unique mixture to the moulding leads to increasing consumption of new sand, respectively to the increase of price of piece. Acording to the dates registered in the industrial practice is necessary to use the special additions to obtain the moulding mixtures, carbonaceous materials respectively.

Prediction of the interaction between a simple moving vehicle and an infinite periodically supported rail - Green's functions approach

NASA Astrophysics Data System (ADS)

Mazilu, Traian

2010-09-01

This paper herein describes the interaction between a simple moving vehicle and an infinite periodically supported rail, in order to signalise the basic features of the vehicle/track vibration behaviour in general, and wheel/rail vibration, in particular. The rail is modelled as an infinite Timoshenko beam resting on semi-sleepers via three-directional rail pads and ballast. The time-domain analysis was performed applying Green's matrix of the track method. This method allows taking into account the nonlinearities of the wheel/rail contact and the Doppler effect. The numerical analysis is dedicated to the wheel/rail response due to two types of excitation: the steady-state interaction and rail irregularities. The study points out to certain aspects regarding the parametric resonance, the amplitude-modulated vibration due to corrugation and the Doppler effect.

Utilization of wheel dop based on ergonomic aspects

NASA Astrophysics Data System (ADS)

Widiasih, Wiwin; Murnawan, Hery; Setiawan, Danny

2017-06-01

Time is an important thing in life. People need a tool or equipment to measure time which is divided into two types, namely clock and watch. Everyone needs those kinds of tool. It becomes an opportunity for manufacturer to build a business. However, establishing a business by depending on the demand is not enough, it is necessary to take a consideration of making innovation. Innovation is a difficult thing to find out, but it is not impossible to do it. By creating an innovative product, it can be a strategy to win the competitive market. This study aimed to create an innovative product based on the ergonomic aspects, which was by utilizing wheel dop. This methodology consisted of pre-study, planning and product development, and product analysis. This product utilized wheel dop and was made based on the ergonomic aspects.

Miniature Blimps for Surveillance and Collection of Samples

NASA Technical Reports Server (NTRS)

Jones, Jack

2004-01-01

Miniature blimps are under development as robots for use in exploring the thick, cold, nitrogen atmosphere of Saturn's moon, Titan. Similar blimps can also be used for surveillance and collection of biochemical samples in buildings, caves, subways, and other, similar structures on Earth. The widely perceived need for means to thwart attacks on buildings and to mitigate the effects of such attacks has prompted consideration of the use of robots. Relative to rover-type (wheeled) robots that have been considered for such uses, miniature blimps offer the advantage of ability to move through the air in any direction and, hence, to perform tasks that are difficult or impossible for wheeled robots, including climbing stairs and looking through windows. In addition, miniature blimps are expected to have greater range and to cost less, relative to wheeled robots.

Effects of acute voluntary loaded wheel running on BDNF expression in the rat hippocampus.

PubMed

Lee, Minchul; Soya, Hideaki

2017-12-31

Voluntary loaded wheel running involves the use of a load during a voluntary running activity. A muscle-strength or power-type activity performed at a relatively high intensity and a short duration may cause fewer apparent metabolic adaptations but may still elicit muscle fiber hypertrophy. This study aimed to determine the effects of acute voluntary wheel running with an additional load on brain-derived neurotrophic factor (BDNF) expression in the rat hippocampus. Ten-week old male Wistar rats were assigned randomly to a (1) sedentary (Control) group; (2) voluntary exercise with no load (No-load) group; or (3) voluntary exercise with an additional load (Load) group for 1-week (acute period). The expression of BDNF genes was quantified by real-time PCR. The average distance levels were not significantly different in the No-load and Load groups. However, the average work levels significantly increased in the Load group. The relative soleus weights were greater in the No-load group. Furthermore, loaded wheel running up-regulated the BDNF mRNA level compared with that in the Control group. The BDNF mRNA levels showed a positive correlation with workload levels (r=0.75), suggesting that the availability of multiple workload levels contributes to the BDNF-related benefits of loaded wheel running noted in this study. This novel approach yielded the first set of findings showing that acute voluntary loaded wheel running, which causes muscular adaptation, enhanced BDNF expression, suggesting a possible role of high-intensity short-term exercise in hippocampal BDNF activity. ©2017 The Korean Society for Exercise Nutrition

Naloxone and rimonabant reduce the reinforcing properties of exercise in rats.

PubMed

Rasmussen, Erin B; Hillman, Conrad

2011-12-01

Naloxone and rimonabant block neurotransmitter action of some drugs of abuse (such as ethanol, opiates, and nicotine), and thereby reduce drug seeking and self-administration by suppressing the drugs' reinforcing properties. The present study represents an attempt to elucidate whether these drugs may also reduce rewarding properties of other events, in this case, activity-based reinforcement. In Experiment 1, 10 obese and 10 lean Zucker rats pressed a locked door under a progressive ratio schedule of reinforcement that, when unlocked, provided access to a running wheel for 2-min intervals. After baseline breakpoints were established, doses of naloxone (0.3-10 mg/kg) were administered prior to experimental sessions. Obese rats exhibited lower baseline breakpoints for wheel activity, lower response rates, and fewer revolutions compared to lean rats. Naloxone decreased revolutions and response rates for lean and obese rats, but did not reduce breakpoints. In Experiment 2, five Long-Evans rats pressed a door to unlock a wheel for 20 s of wheel activity. Doses of rimonabant (1-10 mg/kg) were administered before some experimental sessions. The highest dose of rimonabant suppressed breakpoints and response rates, but did not affect revolutions. These data suggest that both drugs reduce the reinforcing properties of wheel running, but do so in different manners: naloxone may suppress wheel-based activity (consummatory behavior), but not seeking (appetitive behavior), and rimonabant does the converse. The data also support the role of endocannabinoids in the reinforcing properties of exercise, an implication that is important in terms of CB1 antagonists as a type of pharmacotherapy.

Interactive Two-Way mHealth Interventions for Improving Medication Adherence: An Evaluation Using The Behaviour Change Wheel Framework

PubMed Central

Amico, K Rivet; Atkins, Lou; Lester, Richard T

2018-01-01

Background Medication adherence is an important but highly complex set of behaviors, which for life-threatening and infectious diseases such as HIV carry critical consequences for individual and public health. There is growing evidence that mobile phone text messaging interventions (mHealth) connecting providers with patients positively impact medication adherence, particularly two-way engagement platforms that require bidirectional communication versus one-way in which responses are not mandatory. However, mechanisms of action have not been well defined. The Behavior Change Wheel is a comprehensive framework for behavior change that includes an all-encompassing model of behavior known as Capability Opportunity Motivation-Behavior and is complemented by a taxonomy of behavior change techniques. Evaluating mHealth interventions for medication adherence using these tools could provide useful insights that may contribute to optimizing their integration into the healthcare system and successful scaling-up. Objective This study aimed to help address the current knowledge gap regarding how two-way mHealth interventions for medication adherence may work by applying the Behavior Change Wheel to characterize WelTel: an interactive digital health outreach platform with robust evidence for improving adherence to antiretroviral therapy. Methods To characterize how WelTel may promote medication adherence, we applied the Behavior Change Wheel to systematically (1) generate a behavioral diagnosis through mapping known antiretroviral therapy adherence barriers onto the Capability Opportunity Motivation-Behavior model of behavior, (2) specify the behavior change techniques that WelTel delivers, (3) link identified behavior change techniques to corresponding intervention functions of the Behavior Change Wheel, and (4) connect these behavior change techniques and intervention functions to respective Capability Opportunity Motivation-Behavior influences on behavior to determine potential mechanisms of action. Results Our evaluation of WelTel using the Behavior Change Wheel suggests that most of its impact is delivered primarily through its personalized communication component, in which 8 different behavior change techniques were identified and linked with 5 intervention functions (environmental restructuring, enablement, education, persuasion, and training). Its mechanisms of action in promoting antiretroviral therapy adherence may involve addressing all Capability Opportunity Motivation-Behavior influences on behavior (physical and psychological capability, physical and social opportunity, reflective and automatic motivation). Conclusions Systematically unpacking the potential active ingredients of effective interventions facilitates the creation and implementation of more parsimonious, tailored, and targeted approaches. Evaluating WelTel using the Behavior Change Wheel has provided valuable insights into how and why such interactive two-way mHealth interventions may produce greater impact than one-way in addressing both nonintentional and intentional forms of nonadherence. The application of the Behavior Change Wheel for evidence synthesis across mHealth interventions targeting various conditions would contribute to strengthening the knowledge base regarding how they may work to impact medication adherence behavior. PMID:29650504

Interactive Two-Way mHealth Interventions for Improving Medication Adherence: An Evaluation Using The Behaviour Change Wheel Framework.

PubMed

Chiang, Nicole; Guo, Michael; Amico, K Rivet; Atkins, Lou; Lester, Richard T

2018-04-12

Medication adherence is an important but highly complex set of behaviors, which for life-threatening and infectious diseases such as HIV carry critical consequences for individual and public health. There is growing evidence that mobile phone text messaging interventions (mHealth) connecting providers with patients positively impact medication adherence, particularly two-way engagement platforms that require bidirectional communication versus one-way in which responses are not mandatory. However, mechanisms of action have not been well defined. The Behavior Change Wheel is a comprehensive framework for behavior change that includes an all-encompassing model of behavior known as Capability Opportunity Motivation-Behavior and is complemented by a taxonomy of behavior change techniques. Evaluating mHealth interventions for medication adherence using these tools could provide useful insights that may contribute to optimizing their integration into the healthcare system and successful scaling-up. This study aimed to help address the current knowledge gap regarding how two-way mHealth interventions for medication adherence may work by applying the Behavior Change Wheel to characterize WelTel: an interactive digital health outreach platform with robust evidence for improving adherence to antiretroviral therapy. To characterize how WelTel may promote medication adherence, we applied the Behavior Change Wheel to systematically (1) generate a behavioral diagnosis through mapping known antiretroviral therapy adherence barriers onto the Capability Opportunity Motivation-Behavior model of behavior, (2) specify the behavior change techniques that WelTel delivers, (3) link identified behavior change techniques to corresponding intervention functions of the Behavior Change Wheel, and (4) connect these behavior change techniques and intervention functions to respective Capability Opportunity Motivation-Behavior influences on behavior to determine potential mechanisms of action. Our evaluation of WelTel using the Behavior Change Wheel suggests that most of its impact is delivered primarily through its personalized communication component, in which 8 different behavior change techniques were identified and linked with 5 intervention functions (environmental restructuring, enablement, education, persuasion, and training). Its mechanisms of action in promoting antiretroviral therapy adherence may involve addressing all Capability Opportunity Motivation-Behavior influences on behavior (physical and psychological capability, physical and social opportunity, reflective and automatic motivation). Systematically unpacking the potential active ingredients of effective interventions facilitates the creation and implementation of more parsimonious, tailored, and targeted approaches. Evaluating WelTel using the Behavior Change Wheel has provided valuable insights into how and why such interactive two-way mHealth interventions may produce greater impact than one-way in addressing both nonintentional and intentional forms of nonadherence. The application of the Behavior Change Wheel for evidence synthesis across mHealth interventions targeting various conditions would contribute to strengthening the knowledge base regarding how they may work to impact medication adherence behavior. ©Nicole Chiang, Michael Guo, K Rivet Amico, Lou Atkins, Richard T Lester. Originally published in JMIR Mhealth and Uhealth (http://mhealth.jmir.org), 12.04.2018.

Progress in Development of the Axel Rovers

NASA Technical Reports Server (NTRS)

Nesnas, Issa A.; Helmick, Daniel M.; Volpe, Richard A.; Abad-Manterola, Pablo; Edlund, Jeffrey A.

2010-01-01

Progress has been made in the development of a family of robotic land vehicles having modular and minimalist design features chosen to impart a combination of robustness, reliability, and versatility. These vehicles at earlier stages of development were described in two previous NASA Tech Briefs articles: "Reconfigurable Exploratory Robotic Vehicles" (NPO-20944), Vol. 25, No. 7 (July 2001), page 56; and "More About Reconfigurable Exploratory Robotic Vehicles" (NPO-30890), Vol. 33, No. 8 (August 2009), page 40. Conceived for use in exploration of the surfaces of Mars and other remote planets, these vehicles could also be adapted to terrestrial applications, including exploration of volcanic craters or other hostile terrain, military reconnaissance, inspection of hazardous sites, and searching for victims of earthquakes, landslides, avalanches, or mining accidents. In addition, simplified versions of these vehicles might be marketable as toys. The most basic module in this family of reconfigurable robots is the Axel rover, which has a cylindrical body with two main wheels and a trailing link. Inside its body are three motors and associated mechanisms for driving the two wheels and for rotating the link 360 around its symmetrical body. The actuated link serves several purposes: It is used as a lever arm to react to the wheels thrust to move Axel in multiple directions. It is used to rotate the Axel housing in order to tilt, to the desired angle, any sensors and instruments mounted on or in the Axel housing. It provides an alternative mobility mode, which is primarily used in its tethered configuration. Turn ing the link into the ground in lieu of driving the wheels causes the Axel housing and wheels to roll as a unit and thereby leads to a tumbling motion along the ground. With a tether mounted around Axel s cylindrical body, the link serves as a winch mechanism to reel and unreel the tether raising and lowering Axel over steep and vertical surfaces (Figure 1). Sensors, computation, and communication modules are also housed inside Axel s body. A pair of stereo vision cameras provides three-dimensional view for autonomous navigation and avoiding obstacles. Inertial sensors determine the tilt of the robot and are used for estimating its motion. In a fully developed version, power would be supplied by rechargeable batteries aboard Axel; at the time of reporting the information for this article, power was supplied from an external source via a cable. In and of itself, the Axel rover is fully capable of traversing and sampling terrains on planetary surfaces. By use of only the two main wheel actuators and the caster link actuator, Axel can be made to follow an arbitrary path, turn in place, and operate upside- down or right-side-up. If operated in a tethered configuration, as shown in Figure 1, it can be made to move down and up a steep crater wall, descend from an overhang to a cave, and ascend from the cave back to the overhang, all by use of the same three actuators. Such tethered operation could be useful in searching for accident victims or missing persons in mines, caves, and rubble piles. Running the tether through the caster link enhances the stability of Axel and provides a restoring force that keeps the link off the ground for the most part during operation on a steep slope. In its extended configuration, two Axel modules can dock to either side of a payload module to form the four wheeled Axel2 rover (Figure 2). Additional payload and Axel modules can dock to either side of the Axel2 to form the Axel3 rover, extending its payload capacity and its mobility capabilities.

A Learning Tool and Program Development for Mechatronics Design Education

NASA Astrophysics Data System (ADS)

Iribe, Masatsugu; Shirahata, Akihiro; Kita, Hiromasa; Sasashige, Yousuke; Dasai, Ryoichi

In this paper we propose a new type educational program for Mechatronics design which contributes to develop the physical sense and problem solving ability of the students who study Mechatronics design. For this program we provide a new handicraft kit of 4-wheeled car which is composed of inexpensive and commonplace parts, and the performance of the assembled 4-wheeled car is sensitive to its assembly arrangement. And then we implemented this program with the handicraft kit to the university freshmen, and verified its effectiveness, and report the results of the program.

3000-HP Roller Gear Transmission Development Program. Volume 3. Roller Gear Manufacture

DTIC Science & Technology

1975-07-01

power is fed through the ramp roller clutch type free- wheel units to spur gears which mesh with the combining spur gear whose centerline is common...when the engine tends to turn faster than the main rotor shaft. It is in the free- wheel mode when the main rotor shaft tends to turn faster than the...gears are cut progrind at this time. Check face runout on each end of largo gears. Not to exceed .002" TIR 30 EBW one end 40 EBW opposite end

Enhanced voluntary wheel running in GPRC6A receptor knockout mice.

PubMed

Clemmensen, Christoffer; Pehmøller, Christian; Klein, Anders B; Ratner, Cecilia; Wojtaszewski, Jørgen F P; Bräuner-Osborne, Hans

2013-06-13

GPRC6A is an amino acid-sensing receptor highly expressed in the brain and in skeletal muscle. Although recent evidence suggests that genetically engineered GPRC6A receptor knockout (KO) mice are susceptible to develop subtle endocrine and metabolic disturbances, the underlying disruptions in energy metabolism are largely unexplored. Based on GPRC6A's expression pattern and ligand preferences, we hypothesize that the receptor may impact energy metabolism via regulating physical activity levels. Thus, in the present study, we exposed GPRC6A receptor KO mice and their wild-type (WT) littermates to voluntary wheel running and forced treadmill exercise. Moreover, we assessed energy expenditure in the basal state, and evaluated the effects of wheel running on food intake, body composition, and a range of exercise-induced central and peripheral biomarkers. We found that adaptation to voluntary wheel running is affected by GPRC6A, as ablation of the receptor significantly enhances wheel running in KO relative to WT mice. Both genotypes responded to voluntary exercise by increasing food intake and improving body composition to a similar degree. In conclusion, these data demonstrate that the GPRC6A receptor is involved in regulating exercise behaviour. Future studies are highly warranted to delineate the underlying molecular details and to assess if these findings hold any translational value. Copyright © 2013 Elsevier Inc. All rights reserved.

Responding for sucrose and wheel-running reinforcement: effects of sucrose concentration and wheel-running reinforcer duration.

PubMed

Belke, Terry W; Hancock, Stephanie D

2003-03-01

Six male albino rats were placed in running wheels and exposed to a fixed-interval 30-s schedule of lever pressing that produced either a drop of sucrose solution or the opportunity to run for a fixed duration as reinforcers. Each reinforcer type was signaled by a different stimulus. In Experiment 1, the duration of running was held constant at 15 s while the concentration of sucrose solution was varied across values of 0, 2.5. 5, 10, and 15%. As concentration decreased, postreinforcement pause duration increased and local rates decreased in the presence of the stimulus signaling sucrose. Consequently, the difference between responding in the presence of stimuli signaling wheel-running and sucrose reinforcers diminished, and at 2.5%, response functions for the two reinforcers were similar. In Experiment 2, the concentration of sucrose solution was held constant at 15% while the duration of the opportunity to run was first varied across values of 15, 45, and 90 s then subsequently across values of 5, 10, and 15 s. As run duration increased, postreinforcement pause duration in the presence of the wheel-running stimulus increased and local rates increased then decreased. In summary, inhibitory aftereffects of previous reinforcers occurred when both sucrose concentration and run duration varied; changes in responding were attributable to changes in the excitatory value of the stimuli signaling the two reinforcers.

Exploring accessibility issues of a public building for the mobility impaired. Case study: interstate bus terminal (ISBT), Vijayawada, India.

PubMed

Alagappan, Valliappan; Hefferan, Albert; Parivallal, Aarthi

2018-04-01

Right to access in the built environment creates equal and nondiscriminatory opportunities to a person with disabilities in order to move freely around and interact positively without hindrance and barriers. The objective of the study is to understand the existing accessibility related issues and implementation of guidelines and standards for public buildings. The technical verification using onsite and offsite access audit format for current provision of facilities in the internal and external environment has been carried out with the format prepared in reference to Central Public Works Department (CPWD) accessibility guidelines for mobility impaired and elderly and American Disability Act (ADA) guidelines. The access audit format included parameters like accessibility, safety, security, comfort and convenience and it addresses the barriers faced by wheel chair users, people with crutches, prosthetics and with non-assistive devices. The study addressed accessibility compliance in three zones of the building with initiation from parking area zone, inside the building, and area outside the building premises. The findings highlight the environmental barriers encountered by mobility impaired people and represented graphically in the layout plan and physical effort required to overcome the challenges in the built environment. The overall accessibility compliance is 42% in the interstate bus terminal. Implications for rehabilitation The study identifies the environmental limitations, human and technologically facilitators with the help of Central Public Works Department (CPWD) and American Disability Act (ADA) guidelines (1990). It highlights barriers for mobility-impaired users, by demonstrating in a spatial layout and the means to facilitate easy access with minimal frustration, stress and with less physical effort. It demonstrates the need for preparation of separate guidelines for making the existing types of buildings to be access and disabled-friendly. New accessibility guidelines shall be prepared by incorporating concepts like such as relative accessibility into new bus terminal buildings. Guidelines help the disabled in the process of rehabilitation and develop inclusiveness not rather than alienation.

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.

MANPRINT Evaluation of the High Mobility Multipurpose Wheeled Vehicle-Heavy Variant (HMMWV-HV)

DTIC Science & Technology

1990-02-01

gap between brake and gas pedal . Knee hits throttle control. Metal below seat hits back of calf muscle. Visibility Is the driver’s visibility adequate...24, No - 0, NA - 0] Gas pedal : 79. Parked? [Yes - 24, No - 0, NA - 0] 80. Primary and Secondary roads? [Yes - 24, No - 0, NA - 0] 81. Cross-country...Yes - 24, No - 0, NA - 0] 89 Brake pedal : 82. Parked? [Yes - 24, No - 0, NA - 0] 83. Primary and Secondary roads? [Yes - 24, No - 0, NA - 0] 84

The Enabler: A concept for a lunar work vehicle

NASA Technical Reports Server (NTRS)

Brazell, James W.; Campbell, Craig; Kaser, Ken; Austin, James A.; Beard, Clark; Ceniza, Glenn; Hamby, Thomas; Robinson, Anne; Wooters, Dana

1992-01-01

The Enabler is an earthbound prototype designed to model an actual lunar work vehicle and is able to perform many of the tasks that might be expected of a lunar work vehicle. The vehicle will be constructed entirely from parts made by students and from standard stock parts. The design utilizes only four distinct chassis pieces and sixteen moving parts. The Enabler has non-orthogonal articulating joints that give the vehicle a wide range of mobility and reduce the total number of parts. Composite wheels provide the primary suspension system for the vehicle.

Extending the Capability of Mars Umbilical Technology Demonstrator

NASA Technical Reports Server (NTRS)

Houshangi, Nasser

2001-01-01

The objective of this project is to expand the capabilities of for the Mars Umbilical Technology Demonstrator (MUTD). The MUTD shall provide electrical power and fiber optic data cable connections between two simulated mars vehicles, 1000 in apart. ne wheeled mobile robot Omnibot is used to provide the mobile base for the system. The mate-to umbilical plate is mounted on a Cartesian robot, which is installed on the Omnibot mobile base. It is desirable to provide the operator controlling the Omnibot, the distance and direction to the target. In this report, an approach for finding the position and orientation of the mobile robot using inertial sensors and beacons is investigated. First phase of the project considered the Omnibot being on the flat surface. To deal with the uneven Mars environment, the orientation as well as position needs to be controlled. During local positioning, the information received from four ultrasonic sensors installed at the four corner of the mate-mi plate is used to identify the position of mate-to plate and mate the umbilical plates autonomously. The work proposed is the continuation of the principal investigator research effort as a participant in the 1999 NASA/ASEE Summer Faculty Fellowship Program.

Use of mobility aids reduces attentional demand in challenging walking conditions.

PubMed

Miyasike-daSilva, Veronica; Tung, James Y; Zabukovec, Jeanie R; McIlroy, William E

2013-02-01

While mobility aids (e.g., four-wheeled walkers) are designed to facilitate walking and prevent falls in individuals with gait and balance impairments, there is evidence indicating that walkers may increase attentional demands during walking. We propose that walkers may reduce attentional demands under conditions that challenge balance control. This study investigated the effect of walker use on walking performance and attentional demand under a challenged walking condition. Young healthy subjects walked along a straight pathway, or a narrow beam. Attentional demand was assessed with a concurrent voice reaction time (RT) task. Slower RTs, reduced gait speed, and increased number of missteps (>92% of all missteps) were observed during beam-walking. However, walker use reduced attentional demand (faster RTs) and was linked to improved walking performance (increased gait speed, reduced missteps). Data from two healthy older adult cases reveal similar trends. In conclusion, mobility aids can be beneficial by reducing attentional demands and increasing gait stability when balance is challenged. This finding has implications on the potential benefit of mobility aids for persons who rely on walkers to address balance impairments. Copyright © 2012 Elsevier B.V. All rights reserved.

Multi Sensor Fusion Framework for Indoor-Outdoor Localization of Limited Resource Mobile Robots

PubMed Central

Marín, Leonardo; Vallés, Marina; Soriano, Ángel; Valera, Ángel; Albertos, Pedro

2013-01-01

This paper presents a sensor fusion framework that improves the localization of mobile robots with limited computational resources. It employs an event based Kalman Filter to combine the measurements of a global sensor and an inertial measurement unit (IMU) on an event based schedule, using fewer resources (execution time and bandwidth) but with similar performance when compared to the traditional methods. The event is defined to reflect the necessity of the global information, when the estimation error covariance exceeds a predefined limit. The proposed experimental platforms are based on the LEGO Mindstorm NXT, and consist of a differential wheel mobile robot navigating indoors with a zenithal camera as global sensor, and an Ackermann steering mobile robot navigating outdoors with a SBG Systems GPS accessed through an IGEP board that also serves as datalogger. The IMU in both robots is built using the NXT motor encoders along with one gyroscope, one compass and two accelerometers from Hitecnic, placed according to a particle based dynamic model of the robots. The tests performed reflect the correct performance and low execution time of the proposed framework. The robustness and stability is observed during a long walk test in both indoors and outdoors environments. PMID:24152933

Multi sensor fusion framework for indoor-outdoor localization of limited resource mobile robots.

PubMed

Marín, Leonardo; Vallés, Marina; Soriano, Ángel; Valera, Ángel; Albertos, Pedro

2013-10-21

This paper presents a sensor fusion framework that improves the localization of mobile robots with limited computational resources. It employs an event based Kalman Filter to combine the measurements of a global sensor and an inertial measurement unit (IMU) on an event based schedule, using fewer resources (execution time and bandwidth) but with similar performance when compared to the traditional methods. The event is defined to reflect the necessity of the global information, when the estimation error covariance exceeds a predefined limit. The proposed experimental platforms are based on the LEGO Mindstorm NXT, and consist of a differential wheel mobile robot navigating indoors with a zenithal camera as global sensor, and an Ackermann steering mobile robot navigating outdoors with a SBG Systems GPS accessed through an IGEP board that also serves as datalogger. The IMU in both robots is built using the NXT motor encoders along with one gyroscope, one compass and two accelerometers from Hitecnic, placed according to a particle based dynamic model of the robots. The tests performed reflect the correct performance and low execution time of the proposed framework. The robustness and stability is observed during a long walk test in both indoors and outdoors environments.

Optimal braking studies

NASA Technical Reports Server (NTRS)

Pazdera, J. S.

1972-01-01

To brake in minimum distance, the tire slip must be controlled to ride the peak of the mu-slip curve so that maximum ground force is developed between tire and pavement. The resulting control system differs from antiskid systems which react to impending wheel lockup. A simplified model is presented to permit development of a sound control strategy. Liapunov techniques are used to derive a peak riding adaptive controller applicable to each wheel of a breaking vehicle. The controller is applied to a more sophisticated model of a braking airplane with strut bending dynamics included. Simulation results verify the peak riding property of the controller and the rapid adaption of the controller to extreme runway conditions. The effect of actuator dynamics, perturbation frequency, type and location of sensors, absence of a free wheel, and a method in which the pilot's braking commands can be interfaced with the peak riding system are also considered.

The effect of abrading and cutting instruments on machinability of dental ceramics.

PubMed

Sakoda, Satoshi; Nakao, Noriko; Watanabe, Ikuya

2018-03-16

The aim was to investigate the effect of machining instruments on machinability of dental ceramics. Four dental ceramics, including two zirconia ceramics were machined by three types (SiC, diamond vitrified, and diamond sintered) of wheels with a hand-piece engine and two types (diamond and carbide) of burs with a high-speed air turbine. The machining conditions used were abrading speeds of 10,000 and 15,000 r.p.m. with abrading force of 100 gf for the hand-piece engine, and a pressure of 200 kPa and a cutting force of 80 gf for the air-turbine hand-piece. The machinability efficiency was evaluated by volume losses after machining the ceramics. A high-abrading speed had high-abrading efficiency (high-volume loss) compared to low-abrading speed in all abrading instruments used. The diamond vitrified wheels demonstrated higher volume loss for two zirconia ceramics than those of SiC and diamond sintered wheels. When the high-speed air-turbine instruments were used, the diamond points showed higher volume losses compared to the carbide burs for one ceramic and two zirconia ceramics with high-mechanical properties. The results of this study indicated that the machinability of dental ceramics depends on the mechanical and physical properties of dental ceramics and machining instruments. The abrading wheels show autogenous action of abrasive grains, in which ground abrasive grains drop out from the binder during abrasion, then the binder follow to wear out, subsequently new abrasive grains come out onto the instrument surface (autogenous action) and increase the grinding amount (volume loss) of grinding materials.

Equipping an automated wheelchair with an infrared encoder wheel odometer - biomed 2011.

PubMed

Schultz, D; Allen, M; Barrett, S F

2011-01-01

Assistive technology is a rapidly growing field that provides a degree of freedom and self-sufficiency to people of limited mobility. Smart wheelchairs are a subset of assistive technology, and are designed to be operated by people who are unable to use a traditional control system. Instead, smart wheelchairs are equipped with a combination of automated functionality and steering mechanisms specialized to meet a person’s individual needs. One feature common to the automated capabilities of smart wheelchairs is the tracking system. The wheelchair’s microcontroller needs to know how far the chair has travelled, its speed, and the rotational direction of its wheels in order to successfully navigate through an environment. The purpose of this research was to develop an odometer to track the motion of a motorized wheelchair. Due to federal regulations that prohibit changing the structure or internal mechanics of a medical device, the odometer had to be designed as a separate, removable part. The final design for the odometer consisted of two infrared sensors that measure edge transitions of a segmented black and white encoder wheel. The sensor output was then run through two comparator op amps and a high pass filter to produce a clean, crisp square wave signal output. The signal was then fed to an Atmel ATmega164P microcontroller. The microcontroller was programmed to compare the sensor signal with its internal clock, sense edge transitions, and thereby extrapolate the speed, travelled distance, and rotational direction of the wheelchair.

Analysis and experimental kinematics of a skid-steering wheeled robot based on a laser scanner sensor.

PubMed

Wang, Tianmiao; Wu, Yao; Liang, Jianhong; Han, Chenhao; Chen, Jiao; Zhao, Qiteng

2015-04-24

Skid-steering mobile robots are widely used because of their simple mechanism and robustness. However, due to the complex wheel-ground interactions and the kinematic constraints, it is a challenge to understand the kinematics and dynamics of such a robotic platform. In this paper, we develop an analysis and experimental kinematic scheme for a skid-steering wheeled vehicle based-on a laser scanner sensor. The kinematics model is established based on the boundedness of the instantaneous centers of rotation (ICR) of treads on the 2D motion plane. The kinematic parameters (the ICR coefficient , the path curvature variable and robot speed ), including the effect of vehicle dynamics, are introduced to describe the kinematics model. Then, an exact but costly dynamic model is used and the simulation of this model's stationary response for the vehicle shows a qualitative relationship for the specified parameters and . Moreover, the parameters of the kinematic model are determined based-on a laser scanner localization experimental analysis method with a skid-steering robotic platform, Pioneer P3-AT. The relationship between the ICR coefficient and two physical factors is studied, i.e., the radius of the path curvature and the robot speed . An empirical function-based relationship between the ICR coefficient of the robot and the path parameters is derived. To validate the obtained results, it is empirically demonstrated that the proposed kinematics model significantly improves the dead-reckoning performance of this skid-steering robot.

Running Promotes Wakefulness and Increases Cataplexy in Orexin Knockout Mice

PubMed Central

España, Rodrigo A.; McCormack, Sarah L.; Mochizuki, Takatoshi; Scammell, Thomas E.

2007-01-01

Study Objective: People with narcolepsy and mice lacking orexin/hypocretin have disrupted sleep/wake behavior and reduced physical activity. Our objective was to identify physiologic mechanisms through which orexin deficiency reduces locomotor activity. Design: We examined spontaneous wheel running activity and its relationship to sleep/wake behavior in wild type (WT) and orexin knockout (KO) mice. Additionally, given that physical activity promotes alertness, we also studied whether orexin deficiency reduces the wake-promoting effects of exercise. Measurements and Results: Orexin KO mice ran 42% less than WT mice. Their ability to run appeared normal as they initiated running as often as WT mice and ran at normal speeds. However, their running bouts were considerably shorter, and they often had cataplexy or quick transitions into sleep after running. Wheel running increased the total amount of wakefulness in WT and orexin KO mice similarly, however, KO mice continued to have moderately fragmented sleep/wake behavior. Wheel running also doubled the amount of cataplexy by increasing the probability of transitioning into cataplexy. Conclusions: Orexin KO mice run significantly less than normal, likely due to sleepiness, imminent cataplexy, or a reduced motivation to run. Orexin is not required for the wake-promoting effects of wheel running given that both WT and KO mice had similar increases in wakefulness with running wheels. In addition, the clear increase in cataplexy with wheel running suggests the possibility that positive emotions or reward can trigger murine cataplexy, similar to that seen in people and dogs with narcolepsy. Citation: España RA; McCormack SL; Mochizuki T; Scammell TE. Running promotes wakefulness and increases cataplexy in orexin knockout mice. SLEEP 2007;30(11):1417-1425. PMID:18041476

Loss of stability of a railway wheel-set, subcritical or supercritical

NASA Astrophysics Data System (ADS)

Zhang, Tingting; Dai, Huanyun

2017-11-01

Most researches on railway vehicle stability analysis are focused on the codimension 1 (for short, codim 1) bifurcations like subcritical and supercritical Hopf bifurcation. The analysis of codim 1 bifurcation can be completed based on one bifurcation parameter. However, two bifurcation parameters should be considered to give a general view of the motion of the system when it undergoes a degenerate Hopf bifurcation. This kind of bifurcation named the generalised Hopf bifurcation belongs to the codimension 2 (for short, codim 2) bifurcations where two bifurcation parameters need to be taken into consideration. In this paper, we give a numerical analysis of the codim 2 bifurcations of a nonlinear railway wheel-set with the QR algorithm to calculate the eigenvalues of the linearised system incorporating the Golden Cut method and the shooting method to calculate the limit cycles around the Hopf bifurcation points. Here, we found the existence of a generalised Hopf bifurcation where a subcritical Hopf bifurcation turns into a supercritical one with the increase of the bifurcation parameters, which belong to the codim 2 bifurcations, in a nonlinear railway wheel-set model. Only the nonlinear wheel/rail interactive relationship has been taken into consideration in the lateral model that is formulated in this paper. The motion of the wheel-set has been investigated when the bifurcation parameters are perturbed in the neighbourhood of their critical parameters, and the influences of different parameters on critical values of the bifurcation parameters are also given. From the results, it can be seen that the bifurcation types of the wheel-set will change with a variation of the bifurcation parameters in the neighbourhood of their critical values.

3-Dimensional Analysis of Deformation of Disk Wheels and Transverse Force of Wheel Bolts

NASA Astrophysics Data System (ADS)

Kagiwada, Tadao; Harada, Hiroyuki

Loosening of the wheel nuts, which fix the disk wheels of automobiles to the wheel hub, may be the cause of accidents where the wheel falls off while the automobile is running. When the transverse force of wheel bolts exceeds a certain proportion of the bolt shaft force, the wheel nut begins to loosen. Further, the force on the bolt shaft may also be influenced by the loads acting to the wheel through the moment caused by the offset of the wheel. This study determined the 3-dimensional deformation of the disk wheels and the transverse forces on the wheel bolt by 3-dimensional numerical analysis. The results established that the transverse force was influenced by the bolt shaft force caused by the bolt fastening and was superposed on that due to the load, and that it fluctuated greatly during the revolution of the wheel. This phenomenon may be a large factor in the loosening of wheel nuts.

Conservation story takes to the road. [Potomac Edison Co. of Allegheny Power System

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

Not Available

1975-02-15

Potomac Edison Co. personnel designed a compact mobile energy-conservation display that demonstrated energy conservation applications to industry, commerce, government, and educators; this van went on the road in December 1974. Among the displays in the vehicle were a working model of a liquid-heating tank that used floating plastic balls as a cover to conserve heat losses and evaporation, a microwave oven, types of insulation and their applications, and a demand controller designed to reduce consumer peak loads and demand charges. Other displays showed temperature and automatic time controls that could be used in locations unoccupied for various periods of timemore » and lighting applications that stressed use of the most efficient lamps and luminaires and emphasized equipment maintenance; a heat pump, a heat-recovery wheel, heat pipe, and model ''run-around system'' for recovering and reusing heat from various industrial processes were also included. (EAPA Ed. note: as of January 1976, plans were to refurbish, update, and put this van back on the road during the upcoming summer). (MCW)« less

A Hierarchical Model Predictive Tracking Control for Independent Four-Wheel Driving/Steering Vehicles with Coaxial Steering Mechanism

NASA Astrophysics Data System (ADS)

Itoh, Masato; Hagimori, Yuki; Nonaka, Kenichiro; Sekiguchi, Kazuma

2016-09-01

In this study, we apply a hierarchical model predictive control to omni-directional mobile vehicle, and improve the tracking performance. We deal with an independent four-wheel driving/steering vehicle (IFWDS) equipped with four coaxial steering mechanisms (CSM). The coaxial steering mechanism is a special one composed of two steering joints on the same axis. In our previous study with respect to IFWDS with ideal steering, we proposed a model predictive tracking control. However, this method did not consider constraints of the coaxial steering mechanism which causes delay of steering. We also proposed a model predictive steering control considering constraints of this mechanism. In this study, we propose a hierarchical system combining above two control methods for IFWDS. An upper controller, which deals with vehicle kinematics, runs a model predictive tracking control, and a lower controller, which considers constraints of coaxial steering mechanism, runs a model predictive steering control which tracks the predicted steering angle optimized an upper controller. We verify the superiority of this method by comparing this method with the previous method.

Experimental heat and mass transfer of the separated and coupled rotating desiccant wheel and heat wheel

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

Enteria, Napoleon; Yoshino, Hiroshi; Mochida, Akashi

The experimental evaluation of the separated and coupled rotating desiccant wheel and heat wheel is reported. The study aims to investigate the performance of the desiccant wheel and of the heat wheel both when operated separately and jointly. The performance evaluation of the desiccant wheel is based on its moisture removal capacity (MRC), moisture removal regeneration (MRR), and moisture mass balance (MMB). In addition, the study used the total energy balance (TEB), sensible coefficient of performance (COP{sub Sensible}), latent coefficient of performance (COP{sub Latent}) and, total coefficient of performance (COP{sub Total}). The performance of the heat wheel is based onmore » its effectiveness. The COP{sub Sensible}, COP{sub Latent} and, COP{sub Total} are used in the performance evaluation of the coupled desiccant wheel and heat wheel. The general results of the study show that the MRC, MRR and MMB coupled with the TEB, COP{sub Latent}, COP{sub Sensible} and COP{sub Total} predict adequately the performance of the desiccant wheel. In addition, the coupled operation of the desiccant wheel and heat wheel, contributed to the reduction of the external thermal energy requirement for the regeneration of the desiccant wheel. This study can be applied in other researches seeking evaluation of the desiccant wheel, heat wheel, and their combined operation. Moreover, the data presented here are significant for the desiccant wheel benchmarking and for evaluation of the desiccant wheel models. (author)« less

Novel desiccant cooling system using indirect evaporative cooler

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

Belding, W.A.; Delmas, M.P.F.

1997-12-31

An effective desiccant cooling system must efficiently reject adsorption and carryover heat from the process airstream. Rotary heat exchangers are typically used to remove this heat in currently available desiccant equipment, but these devices can leak humid air from the regeneration side of the process into the dry process side, degrading performance. Using a different approach, high cooling capacities and coefficients of performance (COPs) have been achieved in a desiccant cooling system without a heat wheel or bulky stationary heat exchanger. Using a desiccant wheel in conjunction with a compact indirect evaporative cooler and a small air-to-air heat exchanger, amore » cooling system has been developed that eliminates the need for deep dehumidification by the desiccant wheel and at the same time provides 25% to 35% ventilation air to the conditioned space. Using a 0.68 m (27 in.) diameter by 0.2 m (8 in.) deep type 1 M desiccant wheel regenerated at 175 C (347 F), 15.0 kW (4.3 tons) of cooling were achieved with a thermal COP of 0.72. With the addition of a direct evaporative cooler, humidity control over a broad range can be offered by the system. The low desiccant wheel volume and the compact nature of the indirect evaporative coolers result in equipment with a low potential first cost, assuming economies of scale. Equipment presently under development is expected to exceed a gross cooling COP of 0.9.« less

Exploring the impact of wheelchair design on user function in a rural South African setting.

PubMed

Visagie, Surona; Duffield, Svenje; Unger, Mariaan

2015-01-01

Wheelchairs provide mobility that can enhance function and community integration. Function in a wheelchair is influenced by wheelchair design. To explore the impact of wheelchair design on user function and the variables that guided wheelchair prescription in the study setting. A mixed-method, descriptive design using convenience sampling was implemented. Quantitative data were collected from 30 wheelchair users using the functioning every day with a Wheelchair Scale and a Wheelchair Specification Checklist. Qualitative data were collected from ten therapists who prescribed wheelchairs to these users, through interviews. The Kruskal-Wallis test was used to identify relationships, and content analysis was undertaken to identify emerging themes in qualitative data. Wheelchairs with urban designs were issued to 25 (83%) participants. Wheelchair size, fit, support and functional features created challenges concerning transport, operating the wheelchair, performing personal tasks, and indoor and outdoor mobility. Users using wheelchairs designed for use in semi-rural environments achieved significantly better scores regarding the appropriateness of the prescribed wheelchair than those using wheelchairs designed for urban use ( p = <0.01). Therapists prescribed the basic, four-wheel folding frame design most often because of a lack of funding, lack of assessment, lack of skills and user choice. Issuing urban type wheelchairs to users living in rural settings might have a negative effect on users' functional outcomes. Comprehensive assessments, further training and research, on long term cost and quality of life implications, regarding provision of a suitable wheelchair versus a cheaper less suitable option is recommended.

Factors affecting minimum push and pull forces of manual carts.

PubMed

Al-Eisawi, K W; Kerk, C J; Congleton, J J; Amendola, A A; Jenkins, O C; Gaines, W

1999-06-01

The minimum forces needed to manually push or pull a 4-wheel cart of differing weights with similar wheel sizes from a stationary state were measured on four floor materials under different conditions of wheel width, diameter, and orientation. Cart load was increased from 0 to 181.4 kg in increments of 36.3 kg. The floor materials were smooth concrete, tile, asphalt, and industrial carpet. Two wheel widths were tested: 25 and 38 mm. Wheel diameters were 51, 102, and 153 mm. Wheel orientation was tested at four levels: F0R0 (all four wheels aligned in the forward direction), F0R90 (the two front wheels, the wheels furthest from the cart handle, aligned in the forward direction and the two rear wheels, the wheels closest to the cart handle, aligned at 90 degrees to the forward direction), F90R0 (the two front wheels aligned at 90 degrees to the forward direction and the two rear wheels aligned in the forward direction), and F90R90 (all four wheels aligned at 90 degrees to the forward direction). Wheel width did not have a significant effect on the minimum push/pull forces. The minimum push/pull forces were linearly proportional to cart weight, and inversely proportional to wheel diameter. The coefficients of rolling friction were estimated as 2.2, 2.4, 3.3, and 4.5 mm for hard rubber wheels rolling on smooth concrete, tile, asphalt, and industrial carpet floors, respectively. The effect of wheel orientation was not consistent over the tested conditions, but, in general, the smallest minimum push/pull forces were measured with all four wheels aligned in the forward direction, whereas the largest minimum push/pull forces were measured when all four wheels were aligned at 90 degrees to the forward direction. There was no significant difference between the push and pull forces when all four wheels were aligned in the forward direction.

Skin blister formation together with patterned intradermal hematoma: a special type of tire mark injury in victims run over by a wheel.

PubMed

Pircher, R; Epting, T; Schmidt, U; Geisenberger, D; Pollak, S; Kramer, L

2015-04-01

A traffic accident victim run over by a vehicle may show a patterned skin hematoma reflecting the grooves of the tire's profile. Apart from this well-known type of imprint mark, the affected skin can also be blistered provided that the wheel exerts high pressure on the body for a prolonged period of time. The macro- and micromorphological findings as well as the protein composition of the blister fluid were investigated on the basis of a relevant autopsy case. Analogous to blisters associated with hanging marks, the transudation of serous fluid with consecutive detachment of the epidermis is interpreted as a pressure-related effect which cannot be regarded as a sign of vitality. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

ITS Technologies in Military Wheeled Tactical Vehicles: Status Quo and the Future

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

Knee, H.E.

2001-07-02

The U.S. Army operates and maintains the largest trucking fleet in the United States. Its fleet consists of over 246,000 trucks, and it is responsible for buying and developing trucks for all branches of the armed forces. The Army's tactical wheeled vehicle fleet is the logistical backbone of the Army, and annually, the fleet logs about 823 million miles. The fleet consists of a number of types of vehicles. They include eight different families of trucks from the High Mobility Multi-Purpose Wheeled Vehicles to M900 series line haul tractors and special bodies. The average age of all the trucks withinmore » the Army fleet is 15 years, and very few have more than traditional driving instrumentation on-board. Over the past decade, the Department of Transportation's (DOT's) Intelligent Transportation Systems (ITS) Program has conducted research and deployment activities in a number of areas including in-vehicle systems, communication and telematics technologies. Many current model passenger vehicles have demonstrated the assimilation of these technologies to enhance safety and trip quality. Commercial vehicles are also demonstrating many new electronic devices that are assisting in making them safer and more efficient. Moreover, a plethora of new technologies are about to be introduced to drivers that promise greater safety, enhanced efficiency, congestion avoidance, fuel usage reduction, and enhanced trip quality. The U.S. Army has special needs with regard to fleet management, logistics, sustainability, reliability, survivability, and fuel consumption that goes beyond similar requirements within the private industry. In order to effectively apply emerging ITS technologies to the special needs of the U.S. Army, planning for the conduct of the Army's Vehicle Intelligence Program (AVIP) has now commenced. The AVIP will be focused on the conduct of research that: (1) will apply ITS technologies to the special needs of the Army, and (2) will conduct research for special needs wi th regard to vehicle control, driver assistance, integration of vehicle intelligence and robotic technologies, managing effectively the information flow to drivers, enhanced logistics capabilities and sustainability of the Army's fleet during battlefield conditions. This paper will highlight the special needs of the Army, briefly describe two programs, which are embracing ITS technologies to a limited extent, will outline the AVIP, and will provide some insight into future Army vehicle intelligence efforts.« less

TMAP - A Versatile Mobile Robot

NASA Astrophysics Data System (ADS)

Weiss, Joel A.; Simmons, Richard K.

1989-03-01

TMAP, the Teleoperated Mobile All-purpose Platform, provides the Army with a low cost, light weight, flexibly designed, modularly expandable platform for support of maneuver forces and light infantry units. The highly mobile, four wheel drive, diesel-hydraulic platform is controllable at distances of up to 4km from a portable operator control unit using either fiber optic or RF control links. The Martin Marietta TMAP system is based on a hierarchical task decomposition Real-time Control System architecture that readily supports interchange of mission packages and provides the capability for simple incorporation of supervisory control concepts leading to increased system autonomy and resulting force multiplication. TMAP has been designed to support a variety of missions including target designation, anti-armor, anti-air, countermine, and reconnaissance/surveillance. As a target designation system TMAP will provide the soldier with increased survivability and effectiveness by providing substantial combat standoff, and the firepower effectiveness of several manual designator operators. Force-on-force analysis of simulated TMAP engagements indicate that TMAP should provide significant force multiplication for the Army in Air-Land Battle 2000.

Centaur: A Mobile Dexterous Humanoid for Surface Operations

NASA Technical Reports Server (NTRS)

Rehnmark, Fredrik; Ambrose, Robert O.; Goza, S. Michael; Junkin, Lucien; Neuhaus, Peter D.; Pratt, Jerry E.

2005-01-01

Future human and robotic planetary expeditions could benefit greatly from expanded Extra-Vehicular Activity (EVA) capabilities supporting a broad range of multiple, concurrent surface operations. Risky, expensive and complex, conventional EVAs are restricted in both duration and scope by consumables and available manpower, creating a resource management problem. A mobile, highly dexterous Extra-Vehicular Robotic (EVR) system called Centaur is proposed to cost-effectively augment human astronauts on surface excursions. The Centaur design combines a highly capable wheeled mobility platform with an anthropomorphic upper body mounted on a three degree-of-freedom waist. Able to use many ordinary handheld tools, the robot could conserve EVA hours by relieving humans of many routine inspection and maintenance chores and assisting them in more complex tasks, such as repairing other robots. As an astronaut surrogate, Centaur could take risks unacceptable to humans, respond more quickly to EVA emergencies and work much longer shifts. Though originally conceived as a system for planetary surface exploration, the Centaur concept could easily be adapted for terrestrial military applications such as de-Gig, surveillance and other hazardous duties.

Semi-autonomous exploration of multi-floor buildings with a legged robot

NASA Astrophysics Data System (ADS)

Wenger, Garrett J.; Johnson, Aaron M.; Taylor, Camillo J.; Koditschek, Daniel E.

2015-05-01

This paper presents preliminary results of a semi-autonomous building exploration behavior using the hexapedal robot RHex. Stairwells are used in virtually all multi-floor buildings, and so in order for a mobile robot to effectively explore, map, clear, monitor, or patrol such buildings it must be able to ascend and descend stairwells. However most conventional mobile robots based on a wheeled platform are unable to traverse stairwells, motivating use of the more mobile legged machine. This semi-autonomous behavior uses a human driver to provide steering input to the robot, as would be the case in, e.g., a tele-operated building exploration mission. The gait selection and transitions between the walking and stair climbing gaits are entirely autonomous. This implementation uses an RGBD camera for stair acquisition, which offers several advantages over a previously documented detector based on a laser range finder, including significantly reduced acquisition time. The sensor package used here also allows for considerable expansion of this behavior. For example, complete automation of the building exploration task driven by a mapping algorithm and higher level planner is presently under development.

Motion Controlled Gait Enhancing Mobile Shoe for Rehabilitation

PubMed Central

Handzic, Ismet; Vasudevan, Erin V.; Reed, Kyle B.

2011-01-01

Walking on a split-belt treadmill, which has two belts that can be run at different speeds, has been shown to improve walking patterns post-stroke. However, these improvements are only temporarily retained once individuals transition to walking over ground. We hypothesize that longer-lasting effects would be observed if the training occurred during natural walking over ground, as opposed to on a treadmill. In order to study such long-term effects, we have developed a mobile and portable device which can simulate the same gait altering movements experienced on a split-belt treadmill. The new motion controlled gait enhancing mobile shoe improves upon the previous version’s drawbacks. This version of the GEMS has motion that is continuous, smooth, and regulated with on-board electronics. A vital component of this new design is the Archimedean spiral wheel shape that redirects the wearer’s downward force into a horizontal backward motion. The design is passive and does not utilize any motors. Its motion is regulated only by a small magnetic particle brake. Further experimentation is needed to evaluate the long-term after-effects. PMID:22275620

Art on Wheels.

ERIC Educational Resources Information Center

Szekely, George

2002-01-01

Discusses the use of wheels in children's art. Focuses on collecting wheels, ideas for decorating different artworks with wheels, and objects that can move on wheels. Sees wheels as an inspiration for children's art, reflecting on the use of this object in the art classroom. (CMK)

12. INTERIOR VIEW OF SINGLE BAY SLOTTED TYPE FURNACE (LEFT) ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

12. INTERIOR VIEW OF SINGLE BAY SLOTTED TYPE FURNACE (LEFT) AND CHAMBERSBURG DROP HAMMER OPERATED BY JEFF HOHMAN (RIGHT); THE FURNACE IS USED TO PRE-HEAT THE STEEL PRIOR TO FORGING, TOOL IS POST HOLE DIGGER WITH TAMPING BAR - Warwood Tool Company, Foot of Nineteenth Street, Wheeling, Ohio County, WV

A NEW COLLISIONAL RING GALAXY AT z = 0.111: AURIGA'S WHEEL

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

Conn, Blair C.; Pasquali, Anna; Pompei, Emanuela

2011-11-10

We report the serendipitous discovery of a collision ring galaxy, identified as 2MASX J06470249+4554022, which we have dubbed 'Auriga's Wheel', found in a SUPRIME-CAM frame as part of a larger Milky Way survey. This peculiar class of galaxies is the result of a near head-on collision typically between a late-type and an early-type galaxy. Subsequent Gemini Multi-object Spectrograph North long-slit spectroscopy has confirmed both the relative proximity of the components of this interacting pair and has shown that it has a redshift of 0.111. Analysis of the spectroscopy reveals that the late-type galaxy is a LINER class active galactic nucleusmore » (AGN) while the early-type galaxy is also potentially an AGN candidate; this is very uncommon among known collision ring galaxies. Preliminary modeling of the ring finds an expansion velocity of {approx}200 km s{sup -1} consistent with our observations, making the collision about 50 Myr old. The ring currently has a radius of about 10 kpc and a bridge of stars and gas is also visible connecting the two galaxies.« less

Adaptive Gait Control for a Quadruped Robot on 3D Path Planning

NASA Astrophysics Data System (ADS)

Igarashi, Hiroshi; Kakikura, Masayoshi

A legged walking robot is able to not only move on irregular terrain but also change its posture. For example, the robot can pass under overhead obstacles by crouching. The purpose of our research is to realize efficient path planning with a quadruped robot. Therefore, the path planning is expected to extended in three dimensions because of the mobility. However, some issues of the quadruped robot, which are instability, workspace limitation, deadlock and slippage, complicate realizing such application. In order to improve these issues and reinforce the mobility, a new static gait pattern for a quadruped robot, called TFG: Trajectory Following Gait, is proposed. The TFG intends to obtain high controllability like a wheel robot. Additionally, the TFG allows to change it posture during the walk. In this paper, some experimental results show that the TFG improves the issues and it is available for efficient locomotion in three dimensional environment.

Miniature pipe crawler tractor

DOEpatents

McKay, Mark D.; Anderson, Matthew O.; Ferrante, Todd A.; Willis, W. David

2000-01-01

A pipe crawler tractor may comprise a half tractor assembly having a first base drive wheel, a second base drive wheel, and a top drive wheel. The drive wheels are mounted in spaced-apart relation so that the top drive wheel is positioned between the first and second base drive wheels. The mounting arrangement is also such that the first and second base drive wheels contact the inside surface of the pipe at respective first and second positions and so that the top drive wheel contacts the inside surface of the pipe at a third position, the third position being substantially diametrically opposed to the first and second positions. A control system connected to the half tractor assembly controls the rotation of the first base wheel, the second base wheel, and the top drive wheel to move the half tractor assembly within the pipe.

Reduction of extinction and reinstatement of cocaine seeking by wheel running in female rats.

PubMed

Zlebnik, Natalie E; Anker, Justin J; Gliddon, Luke A; Carroll, Marilyn E

2010-03-01

Previous work has shown that wheel running reduced the maintenance of cocaine self-administration in rats. In the present study, the effect of wheel running on extinction and reinstatement of cocaine seeking was examined. Female rats were trained to run in a wheel during 6-h sessions, and they were then catheterized and placed in an operant conditioning chamber where they did not have access to the wheel but were allowed to self-administer iv cocaine. Subsequently, rats were divided into four groups and were tested on the extinction and reinstatement of cocaine seeking while they had varying access to a wheel in an adjoining compartment. The four groups were assigned to the following wheel access conditions: (1) wheel running during extinction and reinstatement (WER), (2) wheel running during extinction and a locked wheel during reinstatement (WE), (3) locked wheel during extinction and wheel running during reinstatement (WR), and (4) locked wheel during extinction and reinstatement (WL). WE and WR were retested later to examine the effect of one session of wheel access on cocaine-primed reinstatement. There were no group differences in wheel revolutions, in rate of acquisition of cocaine self-administration, or in responding during maintenance when there was no wheel access. However, during extinction, WE and WER responded less than WR and WL. WR and WER had lower cocaine-primed reinstatement than WE and WL. One session of wheel exposure in WE also suppressed cocaine-primed reinstatement. Wheel running immediately and effectively reduced cocaine-seeking behavior, but concurrent access to running was necessary. Thus, exercise is a useful and self-sustaining intervention to reduce cocaine-seeking behavior.

Morphologic and chemical composition of particulate matter in motorcycle engine exhaust.

PubMed

Chernyshev, V V; Zakharenko, A M; Ugay, S M; Hien, T T; Hai, L H; Kholodov, A S; Burykina, T I; Stratidakis, A K; Mezhuev, Ya O; Tsatsakis, A M; Golokhvast, K S

2018-01-01

Despite the fact that environmental pollution due to motorcycle exhaust gases reports a great increase, motorcycle production exhibits a great increase through the last years. Countries of Asia and Africa are reported to be the major regions where two-wheeled vehicles are a major transportation mode, with tens of millions of units sold per year. Motorcycle exhaust particles are considered to be the major contributor to environmental pollution due to their airborne dispersion, containing great amount of polycyclic aromatic hydrocarbons (PAHs). This study aims at reporting an objective analysis of the main sources of the ambient air pollution as also particle size distribution and chemical composition analysis of particulate matter originated from the exhausts of two-wheeled vehicles used in the territory of Vladivostok, Russia. Various types of two-wheeled vehicles were examined (motorcycles, ATVs, scooters and wet bikes) using different types of engine and fuel system. Experimental results showed that there was no clear relation to the particle size distribution with the engine displacement of motorcycle and the number of strokes and the fuel system. Instead, there were reported two clear assumptions. The first one is that regarding to the motorcycle brand, a few samples did not exhibit a great percentage of PM 10 fraction. The second one is that more modern vehicles, that have a harmful gas afterburning system, are usually the source of an increased percentage of PM 10 emitted particles. At last, it should be mentioned that the laser particle size analysis method is capable of determining the particle sizes after their agglomeration whereas the optical morphometry method allows to determine the real particle size of emissions. In conclusion, it can be pointed out that the agglomeration of particles can lead to the reduction in the toxicity of particles emissions originated from two wheeled-vehicles.

Progress toward a performance based specification for diamond grinding wheels

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

Taylor, J.S.; Piscotty, M.S.; Blaedel, K.L.

1996-11-12

This work sought to improve the communication between users and makers of fine diamond grinding wheels. A promising avenue for this is to formulate a voluntary product standard that comprises performance indicators that bridge the gap between specific user requirements and the details of wheel formulations. We propose a set of performance specifiers of figures-of-merit, that might be assessed by straightforward and traceable testing methods, but do not compromise proprietary information of the wheel user of wheel maker. One such performance indicator might be wheel hardness. In addition we consider technologies that might be required to realize the benefits ofmore » optimized grinding wheels. A non-contact wheel-to- workpiece proximity sensor may provide a means of monitoring wheel wear and thus wheel position, for wheels that exhibit high wear rates in exchange for improved surface finish.« less

Miniature pipe crawler tractor

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

McKay, M.D.; Anderson, M.O.; Ferrante, T.A.

2000-03-14

A pipe crawler tractor may comprise a half tractor assembly having a first base drive wheel, a second base drive wheel, and a top drive wheel. The drive wheels are mounted in spaced-apart relation so that the top drive wheel is positioned between the first and second base drive wheels. The mounting arrangement is also such that the first and second base drive wheels contact the inside surface of the pipe at respective first and second positions and so that the top drive wheel contacts the inside surface of the pipe at a third position, the third position being substantiallymore » diametrically opposed to the first and second positions. A control system connected to the half tractor assembly controls the rotation of the first base wheel, the second base wheel, and the top drive wheel to move the half tractor assembly within the pipe.« less

27 CFR 555.208 - Construction of type 2 magazines.

Code of Federal Regulations, 2011 CFR

2011-04-01

.... When unattended, vehicular magazines must have wheels removed or otherwise effectively immobilized by... least two inches of hardwood and are to be well braced at the corners. They are to be covered with sheet...

Independent Orbiter Assessment (IOA): CIL issues resolution report, volume 2

NASA Technical Reports Server (NTRS)

1988-01-01

The results of the Independent Orbiter Assessment (IOA) of the Failure Modes And Effects Analysis (FMEA) and Critical Items List (CIL) are presented. This report contains IOA assessment worksheets showing resolution of outstanding IOA CIL issues that were summarized in the IOA FMEA/CIL Assessment Interim Report, dated 9 March 1988. Each assessment worksheet has been updated with CIL issue resolution and rationale. Volume 2 contains the worksheets for the following subsystems: Nose Wheel Steering Subsystem; Remote Manipulator Subsystem; Atmospheric Revitalization Subsystem; Extravehicular Mobility Unit Subsystem; Power Reactant Supply and Distribution Subsystem; Main Propulsion Subsystem; and Orbital Maneuvering Subsystem.

Determining navigability of terrain using point cloud data.

PubMed

Cockrell, Stephanie; Lee, Gregory; Newman, Wyatt

2013-06-01

This paper presents an algorithm to identify features of the navigation surface in front of a wheeled robot. Recent advances in mobile robotics have brought about the development of smart wheelchairs to assist disabled people, allowing them to be more independent. These robots have a human occupant and operate in real environments where they must be able to detect hazards like holes, stairs, or obstacles. Furthermore, to ensure safe navigation, wheelchairs often need to locate and navigate on ramps. The algorithm is implemented on data from a Kinect and can effectively identify these features, increasing occupant safety and allowing for a smoother ride.

Reinforcement value and substitutability of sucrose and wheel running: implications for activity anorexia.

PubMed

Belke, Terry W; Pierce, W David; Duncan, Ian D

2006-09-01

Choice between sucrose and wheel-running reinforcement was assessed in two experiments. In the first experiment, ten male Wistar rats were exposed to concurrent VI 30 s VI 30 s schedules of wheel-running and sucrose reinforcement. Sucrose concentration varied across concentrations of 2.5, 7.5, and 12.5%. As concentration increased, more behavior was allocated to sucrose and more reinforcements were obtained from that alternative. Allocation of behavior to wheel running decreased, but obtained wheel-running reinforcement did not change. Overall, the results suggested that food-deprived rats were sensitive to qualitative changes in food supply (sucrose concentration) while continuing to defend a level of physical activity (wheel running). In the second study, 15 female Long Evans rats were exposed to concurrent variable ratio schedules of sucrose and wheel-running, wheel-running and wheel-running, and sucrose and sucrose reinforcement. For each pair of reinforcers, substitutability was assessed by the effect of income-compensated price changes on consumption of the two reinforcers. Results showed that, as expected, sucrose substituted for sucrose and wheel running substituted for wheel running. Wheel running, however, did not substitute for sucrose; but sucrose partially substituted for wheel running. We address the implications of the interrelationships of sucrose and wheel running for an understanding of activity anorexia.

Reinforcement Value and Substitutability of Sucrose and Wheel Running: Implications for Activity Anorexia

PubMed Central

Belke, Terry W; Duncan, Ian D; David Pierce, W

2006-01-01

Choice between sucrose and wheel-running reinforcement was assessed in two experiments. In the first experiment, ten male Wistar rats were exposed to concurrent VI 30 s VI 30 s schedules of wheel-running and sucrose reinforcement. Sucrose concentration varied across concentrations of 2.5, 7.5, and 12.5%. As concentration increased, more behavior was allocated to sucrose and more reinforcements were obtained from that alternative. Allocation of behavior to wheel running decreased, but obtained wheel-running reinforcement did not change. Overall, the results suggested that food-deprived rats were sensitive to qualitative changes in food supply (sucrose concentration) while continuing to defend a level of physical activity (wheel running). In the second study, 15 female Long Evans rats were exposed to concurrent variable ratio schedules of sucrose and wheel-running, wheel-running and wheel-running, and sucrose and sucrose reinforcement. For each pair of reinforcers, substitutability was assessed by the effect of income-compensated price changes on consumption of the two reinforcers. Results showed that, as expected, sucrose substituted for sucrose and wheel running substituted for wheel running. Wheel running, however, did not substitute for sucrose; but sucrose partially substituted for wheel running. We address the implications of the interrelationships of sucrose and wheel running for an understanding of activity anorexia. PMID:17002224

Separating the effects of shelter from additional cage enhancements for group-housed BALB/cJ mice.

PubMed

Swetter, Brentt J; Karpiak, Christie P; Cannon, J Timothy

2011-05-20

Enrichment studies with rodents have demonstrated that cage enhancements can improve animal welfare and performance on common behavioral measures, but few studies have compared more than one type of enrichment or controlled for confounds, and some have revealed undesirable effects including increased aggression. We compared effects on male (n=51) and female (n=52) BALB/cJ mice of three common additions to a standard home cage: shelter, shelter+running wheel, and shelter+novel objects. Mice in all conditions lived in standard sized cages with 3-4 mice per cage. Males evidenced significant condition effects. Shelter increased longevity and maintained low levels of aggression. Adding a running wheel increased aggression over shelter alone, changed behavior in the elevated plus (EP) and open field (OF), and maintained the improved longevity seen in all shelter conditions. Novel objects impacted behavioral measures compared to the standard condition. An Igloo shelter without running wheel creates a very different home cage environment than the same shelter with the running wheel attached. Shelter, with positive impact on animal welfare, minimal effects on some common behavioral measures, and some positive effects on test variance, warrants consideration for routine inclusion with group-housed BALB/cJ males. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

Maximum Torque and Momentum Envelopes for Reaction Wheel Arrays

NASA Technical Reports Server (NTRS)

Markley, F. Landis; Reynolds, Reid G.; Liu, Frank X.; Lebsock, Kenneth L.

2009-01-01

Spacecraft reaction wheel maneuvers are limited by the maximum torque and/or angular momentum that the wheels can provide. For an n-wheel configuration, the torque or momentum envelope can be obtained by projecting the n-dimensional hypercube, representing the domain boundary of individual wheel torques or momenta, into three dimensional space via the 3xn matrix of wheel axes. In this paper, the properties of the projected hypercube are discussed, and algorithms are proposed for determining this maximal torque or momentum envelope for general wheel configurations. Practical strategies for distributing a prescribed torque or momentum among the n wheels are presented, with special emphasis on configurations of four, five, and six wheels.

A Generic Microdisturbanace Transmissibility Model For Reaction Wheels

NASA Astrophysics Data System (ADS)

Penate Castro, Jose; Seiler, Rene

2012-07-01

The increasing demand for space missions with high- precision pointing requirements for their payload instruments is underlining the importance of studying the impact of micro-level disturbances on the overall performance of spacecraft. For example, a satellite with an optical telescope taking high-resolution images might be very sensitive to perturbations, generated by moving equipment and amplified by the structure of the equipment itself as well as that of the host spacecraft that is accommodating both, the sources of mechanical disturbances and sensitive payload instruments. One of the major sources of mechanical disturbances inside a satellite may be found with reaction wheels. For investigation of their disturbance generation and propagation characteristics, a finite element model with parametric geometry definition has been developed. The model covers the main structural features of typical reaction wheel assemblies and can be used for a transmissibility representation of the equipment. With the parametric geometry definition approach, a wide range of different reaction wheel types and sizes can be analysed, without the need for (re-)defining an individual reaction wheel configuration from scratch. The reaction wheel model can be combined with a finite element model of the spacecraft structure and the payload for an end-to-end modelling and simulation of the microdisturbance generation and propagation. The finite element model has been generated in Patran® Command Language (PCL), which provides a powerful and time-efficient way to change parameters in the model, for creating a new or modifying an existing geometry, without requiring comprehensive manual interactions in the modelling pre-processor. As part of the overall modelling approach, a tailored structural model of the mechanical ball bearings has been implemented, which is one of the more complex problems to deal with, among others, due to the anisotropic stiffness and damping characteristics. Together, with the time and frequency domain representations of the local sources of the disturbance forces and moments (e.g. due to rotor unbalance), the new model enables adequate estimation of the disturbances at the mechanical interface of a reaction wheel with a transmissibility representation, furthermore the analysis of their propagation in a host structure and their effects on a payload item.

Recommendations about Pregnancy from Women with Mobility Disability to Their Peers.

PubMed

Iezzoni, Lisa I; Wint, Amy J; Smeltzer, Suzanne C; Ecker, Jeffrey L

Although growing numbers of women with mobility disability are becoming pregnant and desiring motherhood, relatively little is known about their pregnancy experiences or what they might recommend to other women with mobility disability contemplating pregnancy. Using a semistructured, open-ended interview protocol, we conducted 2-hour telephone interviews with 22 women who had a significant mobility disability before becoming pregnant and had delivered babies within the prior 10 years. We recruited most interviewees through online social networks. We used NVivo software to sort interview transcript texts and performed conventional content analyses to identify major themes. Participants' mean ± standard deviation age was 34.8 ± 5.3 years; most were White, well-educated, and middle income and 18 used wheeled mobility aids. Recommendations for other women with mobility disability coalesced around five themes: recognizing the possibility of giving birth, advocacy and support, being informed, approaches toward obstetrical practitioners, and managing fears about losing custody of their child. Lacking information about what to expect during their pregnancy was a significant problem. Women got information about pregnancy from diverse sources, but questions arose about accuracy and relevance of this information to individual circumstances. Women urged their peers to advocate for their preferences and needs with obstetrical practitioners. Women with mobility disability who had delivered babies offered constructive advice for their peers who desire pregnancy. Increasing availability of accurate and relevant information about pregnancy among women with mobility disability is critically important, as is training obstetrical practitioners to provide patient-centered care to these women during pregnancy. Copyright © 2016 Jacobs Institute of Women's Health. Published by Elsevier Inc. All rights reserved.

Estimating Energy Consumption of Mobile Fluid Power in the United States

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

Lynch, Lauren; Zigler, Bradley T.

This report estimates the market size and energy consumption of mobile off-road applications utilizing hydraulic fluid power, and summarizes technology gaps and implementation barriers. Mobile fluid power is the use of hydraulic fluids under pressure to transmit power in mobile equipment applications. The mobile off-road fluid power sector includes various uses of hydraulic fluid power equipment with fundamentally diverse end-use application and operational requirements, such as a skid steer loader, a wheel loader or an agriculture tractor. The agriculture and construction segments dominate the mobile off-road fluid power market in component unit sales volume. An estimated range of energy consumedmore » by the mobile off-road fluid power sector is 0.36 - 1.8 quads per year, which was 1.3 percent - 6.5 percent of the total energy consumed in 2016 by the transportation sector. Opportunities for efficiency improvements within the fluid power system result from needs to level and reduce the peak system load requirements and develop new technologies to reduce fluid power system level losses, both of which may be facilitated by characterizing duty cycles to define standardized performance test methods. There are currently no commonly accepted standardized test methods for evaluating equipment level efficiency over a duty cycle. The off-road transportation sector currently meets criteria emissions requirements, and there are no efficiency regulations requiring original equipment manufacturers (OEM) to invest in new architecture development to improve the fuel economy of mobile off-road fluid power systems. In addition, the end-user efficiency interests are outweighed by low equipment purchase or lease price concerns, required payback periods, and reliability and durability requirements of new architecture. Current economics, low market volumes with high product diversity, and regulation compliance challenge OEM investment in commercialization of new architecture development.« less

49 CFR 230.114 - Wheel centers.

Code of Federal Regulations, 2013 CFR

2013-10-01

..., following the repair, the crankpin and axle shall remain tight in the wheel. Banding of the hub is permitted... 49 Transportation 4 2013-10-01 2013-10-01 false Wheel centers. 230.114 Section 230.114... Tenders Wheels and Tires § 230.114 Wheel centers. (a) Filling blocks and shims. Driving and trailing wheel...

49 CFR 230.114 - Wheel centers.

Code of Federal Regulations, 2014 CFR

2014-10-01

..., following the repair, the crankpin and axle shall remain tight in the wheel. Banding of the hub is permitted... 49 Transportation 4 2014-10-01 2014-10-01 false Wheel centers. 230.114 Section 230.114... Tenders Wheels and Tires § 230.114 Wheel centers. (a) Filling blocks and shims. Driving and trailing wheel...

49 CFR 230.105 - Lateral motion.

Code of Federal Regulations, 2014 CFR

2014-10-01

... between the hubs of the wheels and the boxes on any pair of wheels shall not exceed the following limits: Inches Engine truck wheels (with swing centers) 1 Engine truck wheels (with rigid centers) 11/2 Trailing truck wheels 1 Driving wheels 3/4 (b) Limits increased. These limits may be increased on steam...

49 CFR 230.114 - Wheel centers.

Code of Federal Regulations, 2012 CFR

2012-10-01

..., following the repair, the crankpin and axle shall remain tight in the wheel. Banding of the hub is permitted... 49 Transportation 4 2012-10-01 2012-10-01 false Wheel centers. 230.114 Section 230.114... Tenders Wheels and Tires § 230.114 Wheel centers. (a) Filling blocks and shims. Driving and trailing wheel...

49 CFR 230.105 - Lateral motion.

Code of Federal Regulations, 2010 CFR

2010-10-01

... between the hubs of the wheels and the boxes on any pair of wheels shall not exceed the following limits: Inches Engine truck wheels (with swing centers) 1 Engine truck wheels (with rigid centers) 11/2 Trailing truck wheels 1 Driving wheels 3/4 (b) Limits increased. These limits may be increased on steam...

49 CFR 230.105 - Lateral motion.

Code of Federal Regulations, 2011 CFR

2011-10-01

... between the hubs of the wheels and the boxes on any pair of wheels shall not exceed the following limits: Inches Engine truck wheels (with swing centers) 1 Engine truck wheels (with rigid centers) 11/2 Trailing truck wheels 1 Driving wheels 3/4 (b) Limits increased. These limits may be increased on steam...

49 CFR 230.114 - Wheel centers.

Code of Federal Regulations, 2011 CFR

2011-10-01

..., following the repair, the crankpin and axle shall remain tight in the wheel. Banding of the hub is permitted... 49 Transportation 4 2011-10-01 2011-10-01 false Wheel centers. 230.114 Section 230.114... Tenders Wheels and Tires § 230.114 Wheel centers. (a) Filling blocks and shims. Driving and trailing wheel...

49 CFR 230.114 - Wheel centers.

Code of Federal Regulations, 2010 CFR

2010-10-01

..., following the repair, the crankpin and axle shall remain tight in the wheel. Banding of the hub is permitted... 49 Transportation 4 2010-10-01 2010-10-01 false Wheel centers. 230.114 Section 230.114... Tenders Wheels and Tires § 230.114 Wheel centers. (a) Filling blocks and shims. Driving and trailing wheel...

49 CFR 230.105 - Lateral motion.

Code of Federal Regulations, 2012 CFR

2012-10-01

... between the hubs of the wheels and the boxes on any pair of wheels shall not exceed the following limits: Inches Engine truck wheels (with swing centers) 1 Engine truck wheels (with rigid centers) 11/2 Trailing truck wheels 1 Driving wheels 3/4 (b) Limits increased. These limits may be increased on steam...

49 CFR 230.105 - Lateral motion.

Code of Federal Regulations, 2013 CFR

2013-10-01

... between the hubs of the wheels and the boxes on any pair of wheels shall not exceed the following limits: Inches Engine truck wheels (with swing centers) 1 Engine truck wheels (with rigid centers) 11/2 Trailing truck wheels 1 Driving wheels 3/4 (b) Limits increased. These limits may be increased on steam...

High-Performance 3D Articulated Robot Display

NASA Technical Reports Server (NTRS)

Powell, Mark W.; Torres, Recaredo J.; Mittman, David S.; Kurien, James A.; Abramyan, Lucy

2011-01-01

In the domain of telerobotic operations, the primary challenge facing the operator is to understand the state of the robotic platform. One key aspect of understanding the state is to visualize the physical location and configuration of the platform. As there is a wide variety of mobile robots, the requirements for visualizing their configurations vary diversely across different platforms. There can also be diversity in the mechanical mobility, such as wheeled, tracked, or legged mobility over surfaces. Adaptable 3D articulated robot visualization software can accommodate a wide variety of robotic platforms and environments. The visualization has been used for surface, aerial, space, and water robotic vehicle visualization during field testing. It has been used to enable operations of wheeled and legged surface vehicles, and can be readily adapted to facilitate other mechanical mobility solutions. The 3D visualization can render an articulated 3D model of a robotic platform for any environment. Given the model, the software receives real-time telemetry from the avionics system onboard the vehicle and animates the robot visualization to reflect the telemetered physical state. This is used to track the position and attitude in real time to monitor the progress of the vehicle as it traverses its environment. It is also used to monitor the state of any or all articulated elements of the vehicle, such as arms, legs, or control surfaces. The visualization can also render other sorts of telemetered states visually, such as stress or strains that are measured by the avionics. Such data can be used to color or annotate the virtual vehicle to indicate nominal or off-nominal states during operation. The visualization is also able to render the simulated environment where the vehicle is operating. For surface and aerial vehicles, it can render the terrain under the vehicle as the avionics sends it location information (GPS, odometry, or star tracking), and locate the vehicle over or on the terrain correctly. For long traverses over terrain, the visualization can stream in terrain piecewise in order to maintain the current area of interest for the operator without incurring unreasonable resource constraints on the computing platform. The visualization software is designed to run on laptops that can operate in field-testing environments without Internet access, which is a frequently encountered situation when testing in remote locations that simulate planetary environments such as Mars and other planetary bodies.

Analysis and Experimental Kinematics of a Skid-Steering Wheeled Robot Based on a Laser Scanner Sensor

PubMed Central

Wang, Tianmiao; Wu, Yao; Liang, Jianhong; Han, Chenhao; Chen, Jiao; Zhao, Qiteng

2015-01-01

Skid-steering mobile robots are widely used because of their simple mechanism and robustness. However, due to the complex wheel-ground interactions and the kinematic constraints, it is a challenge to understand the kinematics and dynamics of such a robotic platform. In this paper, we develop an analysis and experimental kinematic scheme for a skid-steering wheeled vehicle based-on a laser scanner sensor. The kinematics model is established based on the boundedness of the instantaneous centers of rotation (ICR) of treads on the 2D motion plane. The kinematic parameters (the ICR coefficient χ, the path curvature variable λ and robot speed v), including the effect of vehicle dynamics, are introduced to describe the kinematics model. Then, an exact but costly dynamic model is used and the simulation of this model’s stationary response for the vehicle shows a qualitative relationship for the specified parameters χ and λ. Moreover, the parameters of the kinematic model are determined based-on a laser scanner localization experimental analysis method with a skid-steering robotic platform, Pioneer P3-AT. The relationship between the ICR coefficient χ and two physical factors is studied, i.e., the radius of the path curvature λ and the robot speed v. An empirical function-based relationship between the ICR coefficient of the robot and the path parameters is derived. To validate the obtained results, it is empirically demonstrated that the proposed kinematics model significantly improves the dead-reckoning performance of this skid–steering robot. PMID:25919370

Thermal fatigue performance of integrally cast automotive turbine wheels

NASA Technical Reports Server (NTRS)

Humphreys, V. E.; Hofer, K. E.

1980-01-01

Fluidized bed thermal fatigue testing was conducted on 16 integrally cast automotive turbine wheels for 1000-10,000 (600 sec total) thermal cycles at 935/50 C. The 16 wheels consisted of 14 IN-792 + 1% Hf and 2 gatorized AF2-1DA wheels; 6 of the IN-792 + Hf wheels contained crack arrest pockets inside the blade root flange. Temperature transients during the thermal cycling were measured in three calibration tests using either 18 or 30 thermocouples per wheel. Thermal cracking based on crack length versus accumulated cycles was greatest for unpocketed wheels developing cracks in 8-13 cycles compared to 75-250 cycles for unpocketed wheels. However, pocketed wheels survived up to 10,000 cycles with crack lengths less than 20 mm, whereas two unpocketed wheels developed 45 mm long cracks in 1000-2000 cycles.

[Sleepiness, safety on the road and management of risk].

PubMed

Garbarino, S; Traversa, F; Spigno, F

2012-01-01

Public health studies have shown that sleepiness at the wheel and other risks associated with sleep are responsible for 5% to 30% of road accidents, depending on the type of driver and/or road. In industrialized countries one-fifth of all traffic accidents can be ascribed to sleepiness behind the wheel. Sleep disorders and various common acute and chronic medical conditions together with lifestyles, extended work hours and prolonged wakefulness directly or indirectly affect the quality and quantity of one's sleep increasing the number of workers with sleep debt and staggered hours. These conditions may increase the risk of road accidents. Strategies to reduce this risk of both commercial and non-commercial drivers related to sleepiness include reliable diagnosis and treatment of sleep disorders, management of chronobiological conflicts, adequate catch-up sleep, and countermeasures against sleepiness at the wheel. Road transport safety requires the adoption of occupational health measures, including risk assessment, health education, technical-environmental prevention and health surveillance.

Avoiding the Health Hazard of People from Construction Vehicles: A Strategy for Controlling the Vibration of a Wheel Loader

PubMed Central

Chi, Feng; Zhou, Jun; Zhang, Qi; Wang, Yong; Huang, Panling

2017-01-01

The vibration control of a construction vehicle must be carried out in order to meet the aims of sustainable environmental development and to avoid the potential human health hazards. In this paper, based on market feedback, the driver seat vibration of a type of wheel loader in the left and right direction, is found to be significant over a certain speed range. In order to find abnormal vibration components, the order tracking technique (OTT) and transmission path analysis (TPA) were used to analyze the vibration sources of the wheel loader. Through this analysis, it can be seen that the abnormal vibration comes from the interaction between the tire tread and the road, and this is because the vibration was amplified by the cab mount, which was eventually transmitted to the cab seat. Finally, the seat vibration amplitudes were decreased by up to 50.8%, after implementing the vibration reduction strategy. PMID:28282849

Avoiding the Health Hazard of People from Construction Vehicles: A Strategy for Controlling the Vibration of a Wheel Loader.

PubMed

Chi, Feng; Zhou, Jun; Zhang, Qi; Wang, Yong; Huang, Panling

2017-03-08

The vibration control of a construction vehicle must be carried out in order to meet the aims of sustainable environmental development and to avoid the potential human health hazards. In this paper, based on market feedback, the driver seat vibration of a type of wheel loader in the left and right direction, is found to be significant over a certain speed range. In order to find abnormal vibration components, the order tracking technique (OTT) and transmission path analysis (TPA) were used to analyze the vibration sources of the wheel loader. Through this analysis, it can be seen that the abnormal vibration comes from the interaction between the tire tread and the road, and this is because the vibration was amplified by the cab mount, which was eventually transmitted to the cab seat. Finally, the seat vibration amplitudes were decreased by up to 50.8%, after implementing the vibration reduction strategy.

Simulation development and evaluation of an improved longitudinal velocity vector control wheel steering mode and electronic display format

NASA Technical Reports Server (NTRS)

Steinmetz, G. G.

1980-01-01

Using simulation, an improved longitudinal velocity vector control wheel steering mode and an improved electronic display format for an advanced flight system were developed and tested. Guidelines for the development phase were provided by test pilot critique summaries of the previous system. The results include performances from computer generated step column inputs across the full airplane speed and configuration envelope, as well as piloted performance results taken from a reference line tracking task and an approach to landing task conducted under various environmental conditions. The analysis of the results for the reference line tracking and approach to landing tasks indicates clearly detectable improvement in pilot tracking accuracy with a reduction in physical workload. The original objectives of upgrading the longitudinal axis of the velocity vector control wheel steering mode were successfully met when measured against the test pilot critique summaries and the original purpose outlined for this type of augment control mode.

A Backpack-Mounted Omnidirectional Camera with Off-the-Shelf Navigation Sensors for Mobile Terrestrial Mapping: Development and Forest Application

PubMed Central

Prol, Fabricio dos Santos; El Issaoui, Aimad; Hakala, Teemu

2018-01-01

The use of Personal Mobile Terrestrial System (PMTS) has increased considerably for mobile mapping applications because these systems offer dynamic data acquisition with ground perspective in places where the use of wheeled platforms is unfeasible, such as forests and indoor buildings. PMTS has become more popular with emerging technologies, such as miniaturized navigation sensors and off-the-shelf omnidirectional cameras, which enable low-cost mobile mapping approaches. However, most of these sensors have not been developed for high-accuracy metric purposes and therefore require rigorous methods of data acquisition and data processing to obtain satisfactory results for some mapping applications. To contribute to the development of light, low-cost PMTS and potential applications of these off-the-shelf sensors for forest mapping, this paper presents a low-cost PMTS approach comprising an omnidirectional camera with off-the-shelf navigation systems and its evaluation in a forest environment. Experimental assessments showed that the integrated sensor orientation approach using navigation data as the initial information can increase the trajectory accuracy, especially in covered areas. The point cloud generated with the PMTS data had accuracy consistent with the Ground Sample Distance (GSD) range of omnidirectional images (3.5–7 cm). These results are consistent with those obtained for other PMTS approaches. PMID:29522467

Diamond grinding wheels production study with the use of the finite element method.

PubMed

Kundrák, J; Fedorovich, V; Markopoulos, A P; Pyzhov, I; Kryukova, N

2016-11-01

Research results on 3D modeling of the diamond grain and its bearing layer when sintering diamond grinding wheels are provided in this paper. The influence of the main characteristics of the wheel materials and the wheel production process, namely the quantity of metallic phase within diamond grain, coefficient of thermal expansion of the metallic phase, the modulus of elasticity of bond material and sintering temperature, on the internal stresses arising in grains is investigated. The results indicate that the stresses in the grains are higher in the areas around the metallic phase. Additionally, sintering temperature has the greatest impact on the stresses of the grain-metallic phase-bond system regardless of the type of the bond. Furthermore, by employing factorial design for the carried out finite element model, a mathematical model that reflects the impact of these factors on the deflected mode of the diamond grain-metallic phase-bond material system is obtained. The results of the analysis allow for the identification of optimal conditions for the efficient production of improved diamond grinding wheels. More specifically, the smallest stresses are observed when using the metal bond with modulus of elasticity 204 GPa, the quantity of metallic phase in diamond grain of not higher than 7% and coefficient of thermal expansion of 1.32 × 10 -5  1/K or lower. The results obtained from the proposed 3D model can lead to the increase in the diamond grains utilization and improve the overall efficiency of diamond grinding.

Maximum Torque and Momentum Envelopes for Reaction Wheel Arrays

NASA Technical Reports Server (NTRS)

Reynolds, R. G.; Markley, F. Landis

2001-01-01

Spacecraft reaction wheel maneuvers are limited by the maximum torque and/or angular momentum which the wheels can provide. For an n-wheel configuration, the torque or momentum envelope can be obtained by projecting the n-dimensional hypercube, representing the domain boundary of individual wheel torques or momenta, into three dimensional space via the 3xn matrix of wheel axes. In this paper, the properties of the projected hypercube are discussed, and algorithms are proposed for determining this maximal torque or momentum envelope for general wheel configurations. Practical implementation strategies for specific wheel configurations are also considered.

Wheel speed management control system for spacecraft

NASA Technical Reports Server (NTRS)

Goodzeit, Neil E. (Inventor); Linder, David M. (Inventor)

1991-01-01

A spacecraft attitude control system uses at least four reaction wheels. In order to minimize reaction wheel speed and therefore power, a wheel speed management system is provided. The management system monitors the wheel speeds and generates a wheel speed error vector. The error vector is integrated, and the error vector and its integral are combined to form a correction vector. The correction vector is summed with the attitude control torque command signals for driving the reaction wheels.

77 FR 75696 - Petition for Waiver of Compliance

Federal Register 2010, 2011, 2012, 2013, 2014

2012-12-21

....'s Pine Street Yard in Orrville, OH, on the Wheeling and Lake Erie Railway. There are two end windows... eight windows each. No Type I or Type II FRA-certified glazing is currently installed in the car. However, all side windows are \\1/4\\-inch panes of Duplate ASI PPG Safety Glass. Some of these side windows...

77 FR 75698 - Petition for Waiver of Compliance

Federal Register 2010, 2011, 2012, 2013, 2014

2012-12-21

..., Inc. Pine Street Yard in Orrville, OH, on Wheeling and Lake Erie Railway. There are no end windows except for the end doors. The left side of the car contains six windows while the right side contains seven windows. No Type I or Type II FRA-certified glazing is currently installed in the car. All windows...

Limiting Forces on Transit Trucks in Steady-State Curving

DOT National Transportation Integrated Search

1981-05-01

This study develops conservative bounds on wheel/rail forces and flange forces for several types of rigid and flexible trucks in steady-state curving conditions. The approximate analysis presented provides closed-form relations for estimating forces,...

Molecular growth from a Mo176 to a Mo248 cluster

NASA Astrophysics Data System (ADS)

Müller, A.; Shah, Syed Q. N.; Bögge, H.; Schmidtmann, M.

1999-01-01

In polyoxometalate chemistry a large variety of compounds, clusters and solid-state structures can be formed by the linking together of well-defined metal-oxygen building blocks, . These species exhibit unusual topological and electronic properties, andfind applications ranging from medicine to industrial processes. The recently reported ring-shaped mixed-valence polyoxomolybdates of the type {Mo154} (refs 5, 6) and {Mo176} (refs 7, 8) represent a new class of giant clusters with nanometre-sized cavities and interesting properties for host-guest chemistry. Here we describe the formation of related clusters of the type {Mo248} formed by addition of further units to the inner surface of the {Mo176 } `wheel'. The additional units arrange themselves into two {Mo36} `hub-caps' on the initial wheel-clusters that are not stable in isolation. These findings reveal a new pathway to the development of complex coordination clusters.

49 CFR 230.113 - Wheels and tire defects.

Code of Federal Regulations, 2012 CFR

2012-10-01

... crack or break in the flange, tread, rim, plate, hub or brackets. (b) Flat spots. Wheels and tires may... 49 Transportation 4 2012-10-01 2012-10-01 false Wheels and tire defects. 230.113 Section 230.113... Tenders Wheels and Tires § 230.113 Wheels and tire defects. Steam locomotive and tender wheels or tires...

49 CFR 215.103 - Defective wheel.

Code of Federal Regulations, 2012 CFR

2012-10-01

... less; (d) A wheel rim, flange, plate, or hub area on the car has a crack or break; (e) A wheel on the... 49 Transportation 4 2012-10-01 2012-10-01 false Defective wheel. 215.103 Section 215.103... § 215.103 Defective wheel. A railroad may not place or continue in service a car, if— (a) A wheel flange...

49 CFR 230.113 - Wheels and tire defects.

Code of Federal Regulations, 2010 CFR

2010-10-01

... crack or break in the flange, tread, rim, plate, hub or brackets. (b) Flat spots. Wheels and tires may... 49 Transportation 4 2010-10-01 2010-10-01 false Wheels and tire defects. 230.113 Section 230.113... Tenders Wheels and Tires § 230.113 Wheels and tire defects. Steam locomotive and tender wheels or tires...

49 CFR 215.103 - Defective wheel.

Code of Federal Regulations, 2011 CFR

2011-10-01

... less; (d) A wheel rim, flange, plate, or hub area on the car has a crack or break; (e) A wheel on the... 49 Transportation 4 2011-10-01 2011-10-01 false Defective wheel. 215.103 Section 215.103... § 215.103 Defective wheel. A railroad may not place or continue in service a car, if— (a) A wheel flange...

49 CFR 230.113 - Wheels and tire defects.

Code of Federal Regulations, 2014 CFR

2014-10-01

... crack or break in the flange, tread, rim, plate, hub or brackets. (b) Flat spots. Wheels and tires may... 49 Transportation 4 2014-10-01 2014-10-01 false Wheels and tire defects. 230.113 Section 230.113... Tenders Wheels and Tires § 230.113 Wheels and tire defects. Steam locomotive and tender wheels or tires...

49 CFR 230.113 - Wheels and tire defects.

Code of Federal Regulations, 2013 CFR

2013-10-01

... crack or break in the flange, tread, rim, plate, hub or brackets. (b) Flat spots. Wheels and tires may... 49 Transportation 4 2013-10-01 2013-10-01 false Wheels and tire defects. 230.113 Section 230.113... Tenders Wheels and Tires § 230.113 Wheels and tire defects. Steam locomotive and tender wheels or tires...

49 CFR 215.103 - Defective wheel.

Code of Federal Regulations, 2010 CFR

2010-10-01

... less; (d) A wheel rim, flange, plate, or hub area on the car has a crack or break; (e) A wheel on the... 49 Transportation 4 2010-10-01 2010-10-01 false Defective wheel. 215.103 Section 215.103... § 215.103 Defective wheel. A railroad may not place or continue in service a car, if— (a) A wheel flange...

49 CFR 230.113 - Wheels and tire defects.

Code of Federal Regulations, 2011 CFR

2011-10-01

... crack or break in the flange, tread, rim, plate, hub or brackets. (b) Flat spots. Wheels and tires may... 49 Transportation 4 2011-10-01 2011-10-01 false Wheels and tire defects. 230.113 Section 230.113... Tenders Wheels and Tires § 230.113 Wheels and tire defects. Steam locomotive and tender wheels or tires...

49 CFR 215.103 - Defective wheel.

Code of Federal Regulations, 2014 CFR

2014-10-01

... less; (d) A wheel rim, flange, plate, or hub area on the car has a crack or break; (e) A wheel on the... 49 Transportation 4 2014-10-01 2014-10-01 false Defective wheel. 215.103 Section 215.103... § 215.103 Defective wheel. A railroad may not place or continue in service a car, if— (a) A wheel flange...

49 CFR 215.103 - Defective wheel.

Code of Federal Regulations, 2013 CFR

2013-10-01

... less; (d) A wheel rim, flange, plate, or hub area on the car has a crack or break; (e) A wheel on the... 49 Transportation 4 2013-10-01 2013-10-01 false Defective wheel. 215.103 Section 215.103... § 215.103 Defective wheel. A railroad may not place or continue in service a car, if— (a) A wheel flange...