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Sample records for head mounted display

  1. Maintenance Procedure Display: Head Mounted Display (HMD) Evaluations

    NASA Technical Reports Server (NTRS)

    Whitmore, Milrian; Litaker, Harry L., Jr.; Solem, Jody A.; Holden, Kritina L.; Hoffman, Ronald R.

    2007-01-01

    A viewgraph presentation describing maintenance procedures for head mounted displays is shown. The topics include: 1) Study Goals; 2) Near Eye Displays (HMDs); 3) Design; 4) Phase I-Evaluation Methods; 5) Phase 1 Results; 6) Improved HMD Mounting; 7) Phase 2 -Evaluation Methods; 8) Phase 2 Preliminary Results; and 9) Next Steps.

  2. Designing a Vibrotactile Head-mounted Display.

    PubMed

    de Jesus Oliveira, Victor; Brayda, Luca; Nedel, Luciana; Maciel, Anderson

    2017-01-23

    Due to the perceptual characteristics of the head, vibrotactile Head-mounted Displays are built with low actuator density. Therefore, vibrotactile guidance is mostly assessed by pointing towards objects in the azimuthal plane. When it comes to multisensory interaction in 3D environments, it is also important to convey information about objects in the elevation plane. In this paper, we design and assess a haptic guidance technique for 3D environments. First, we explore the modulation of vibration frequency to indicate the position of objects in the elevation plane. Then, we assessed a vibrotactile HMD made to render the position of objects in a 3D space around the subject by varying both stimulus loci and vibration frequency. Results have shown that frequencies modulated with a quadratic growth function allowed a more accurate, precise, and faster target localization in an active head pointing task. The technique presented high usability and a strong learning effect for a haptic search across different scenarios in an immersive VR setup.

  3. Combat vehicle crew helmet-mounted display: next generation high-resolution head-mounted display

    NASA Astrophysics Data System (ADS)

    Nelson, Scott A.

    1994-06-01

    The Combat Vehicle Crew Head-Mounted Display (CVC HMD) program is an ARPA-funded, US Army Natick Research, Development, and Engineering Center monitored effort to develop a high resolution, flat panel HMD for the M1 A2 Abrams main battle tank. CVC HMD is part of the ARPA High Definition Systems (HDS) thrust to develop and integrate small (24 micrometers square pels), high resolution (1280 X 1024 X 6-bit grey scale at 60 frame/sec) active matrix electroluminescent (AMEL) and active matrix liquid crystal displays (AMLCD) for head mounted and projection applications. The Honeywell designed CVC HMD is a next generation head-mounted display system that includes advanced flat panel image sources, advanced digital display driver electronics, high speed (> 1 Gbps) digital interconnect electronics, and light weight, high performance optical and mechanical designs. The resulting dramatic improvements in size, weight, power, and cost have already led to program spin offs for both military and commercial applications.

  4. Head-Mounted and Head-Up Display Glossary

    NASA Technical Reports Server (NTRS)

    Newman, Richard L.; Allen, J. Edwin W. (Technical Monitor)

    1997-01-01

    One of the problems in head-up and helmet-mounted display (HMD) literature has been a lack of standardization of words and abbreviations. Several different words have been used for the same concept; for example, flight path angle, flight path marker, velocity vector, and total velocity vector all refer to the same thing. In other cases, the same term has been used with two different meanings, such as binocular field-of-view which means the field-of-view visible to both left and right eyes according to some or the field-of-view visible to either the left or right eye or both according to others. Many of the terms used in HMD studies have not been well-defined. We need to have a common language to ensure that system descriptions are communicated. As an example, the term 'stabilized' has been widely used with two meanings. 'Roll-stabilized' has been used to mean a symbol which rotates to indicate the roll or bank of the aircraft. 'World-stabilized' and 'head-stabilized' have both been used to indicate symbols which move to remain fixed with respect to external objects. HMDs present unique symbology problems not found in HUDs. Foremost among these is the issue of maintaining spatial orientation of the symbols. All previous flight displays, round dial instruments, HDDs, and HUDs have been fixed in the cockpit. With the HMD, the flight display can move through a large angle. The coordinates use in transforming from the real-world to the aircraft to the HMD have not been consistently defined. This glossary contains terms relating to optics and vision, displays, and flight information, weapons and aircraft systems. Some definitions, such as Navigation Display, have been added to clarify the definitions for Primary Flight Display and Primary Flight Reference. A list of HUD/HMD related abbreviations is also included.

  5. Head Mounted Display with a Roof Mirror Array Fold

    NASA Technical Reports Server (NTRS)

    Olczak, Eugene (Inventor)

    2014-01-01

    The present invention includes a head mounted display (HMD) worn by a user. The HMD includes a display projecting an image through an optical lens. The HMD also includes a one-dimensional retro reflective array receiving the image through the optical lens at a first angle with respect to the display and deflecting the image at a second angle different than the first angle with respect to the display. The one-dimensional retro reflective array reflects the image in order to project the image onto an eye of the user.

  6. Head-mounted workstation displays for airborne reconnaissance applications

    NASA Astrophysics Data System (ADS)

    Browne, Michael P.

    1998-09-01

    Aircraft reconnaissance operators need to access increasing amounts of information to perform their job effectively. Unfortunately, there is no excess weight, space or power capacity in most airborne platforms for the installation of additional display surfaces. Head mounted workstation displays solve these weight, space and power problems and mitigate information overload by providing a user-friendly interface to displayed information. Savings can be tremendous for large platforms. Over 18 kW of power and over 5,000 pounds could be saved on each Rivet Joint or AWACS platform. Even small platforms such as the E-2C or UAV ground control stations benefit from removal of large, heavy CRT or LCD displays. In addition, head mounted workstation displays provide an increased capability for collaborative mission planning and reduce motion-induced nausea. Kaiser Electronics has already designed and demonstrated a prototype system, VIEWTM, that addresses the needs of the airborne workstation operator. This system is easily reconfigured for multiple tasks and can be designed as a portable workstation for use anywhere within the aircraft (especially for maintenance or supervisory roles). We have validated the VIEWTM design with hundreds of user trials within the airborne reconnaissance community. Adopting such a display system in reconnaissance aircraft will gain significant benefits such as longer on-station time, increased operational altitude and improved operator performance.

  7. 3D head mount display with single panel

    NASA Astrophysics Data System (ADS)

    Wang, Yuchang; Huang, Junejei

    2014-09-01

    The head mount display for entertainment usually requires light weight. But in the professional application has more requirements. The image quality, field of view (FOV), color gamut, response and life time are considered items, too. A head mount display based on 1-chip TI DMD spatial light modulator is proposed. The multiple light sources and splitting images relay system are the major design tasks. The relay system images the object (DMD) into two image planes to crate binocular vision. The 0.65 inch 1080P DMD is adopted. The relay has a good performance which includes the doublet to reduce the chromatic aberration. Some spaces are reserved for placing the mirror and adjustable mechanism. The mirror splits the rays to the left and right image plane. These planes correspond to the eyepieces objects and image to eyes. A changeable mechanism provides the variable interpupillary distance (IPD). The folding optical path makes sure that the HMD center of gravity is close to the head and prevents the uncomfortable downward force being applied to head or orbit. Two RGB LED assemblies illuminate to the DMD in different angle. The light is highly collimated. The divergence angle is small enough such that one LED ray would only enters to the correct eyepiece. This switching is electronic controlled. There is no moving part to produce vibration and fast switch would be possible. Two LED synchronize with 3D video sync by a driving board which also controls the DMD. When the left eye image is displayed on DMD, the LED for left optical path turns on. Vice versa for right image and 3D scene is accomplished.

  8. Head-mounted display systems and the special operations soldier

    NASA Astrophysics Data System (ADS)

    Loyd, Rodney B.

    1998-08-01

    In 1997, the Boeing Company, working with DARPA under the Smart Modules program and the US Army Soldier Systems Command, embarked on an advanced research and development program to develop a wearable computer system tailored for use with soldiers of the US Special Operations Command. The 'special operations combat management system' is a rugged advanced wearable tactical computer, designed to provide the special operations soldier with enhanced situation awareness and battlefield information capabilities. Many issues must be considered during the design of wearable computers for a combat soldier, including the system weight, placement on the body with respect to other equipment, user interfaces and display system characteristics. During the initial feasibility study for the system, the operational environment was examined and potential users were interviewed to establish the proper display solution for the system. Many display system requirements resulted, such as head or helmet mounting, Night Vision Goggle compatibility, minimal visible light emissions, environmental performance and even the need for handheld or other 'off the head' type display systems. This paper will address these issues and other end user requirements for display systems for applications in the harsh and demanding environment of the Special Operations soldier.

  9. Gradient index eyepiece technology for head-mounted display applications

    NASA Astrophysics Data System (ADS)

    Marasco, Peter L.

    2014-06-01

    Eyepieces used in full color head-mounted displays require a high degree achromatization to exhibit the level of performance required by observers. Many times, this leads to the use of dense glass materials and multi-element systems. The advent of new gradient index material systems as part of the DARPA-sponsored Manufacturable Gradient Index Optics (M-GRIN) may yield new design degrees of freedom for eyepiece and HMD designers. New plastic material systems may be used to simplify eyepiece design and shorten the eyepiece overall length, pulling the entire HMD system closer to the observer's head and improving systems center of gravity. This paper will examine the possibility of using large aperture GRIN optics to achromatize an eyepiece and reduce its overall mass. Assumptions about the material system (index of refraction (n) and delta n) and a candidate full color microdisplay will be clearly stated and may not reflect any commercially available system.

  10. Head-mounted display (HMD) assessment for tracked vehicles

    NASA Astrophysics Data System (ADS)

    Nicholson, Gail

    2011-06-01

    Providing the warfighter with Head or Helmet Mounted Displays (HMDs) while in tracked vehicles provides a means to visually maintain access to systems information while in a high vibration environment. The high vibration and unique environment of military tracked and turreted vehicles impact the ability to distinctly see certain information on an HMD, especially small font size or graphics and information that requires long fixation (staring), rather than a brief or peripheral glance. The military and commercial use of HMDs was compiled from market research, market trends, and user feedback. Lessons learned from previous military and commercial use of HMD products were derived to determine the feasibility of HMDs use in the high vibration and the unique environments of tracked vehicles. The results are summarized into factors that determine HMD features which must be specified for successful implementation.

  11. Gaze contingent hologram synthesis for holographic head-mounted display

    NASA Astrophysics Data System (ADS)

    Hong, Jisoo; Kim, Youngmin; Hong, Sunghee; Shin, Choonsung; Kang, Hoonjong

    2016-03-01

    Development of display and its related technologies provides immersive visual experience with head-mounted-display (HMD). However, most available HMDs provide 3D perception only by stereopsis, lack of accommodation depth cues. Recently, holographic HMD (HHMD) arises as one viable option to resolve this problem because hologram is known to provide full set of depth cues including accommodation. Moreover, by virtue of increasing computational power, hologram synthesis from 3D object represented by point cloud can be calculated in real time even with rigorous Rayleigh-Sommerfeld diffraction formula. However, in HMD, rapid gaze change of the user requires much faster refresh rate, which means that much faster hologram synthesis is indispensable in HHMD. Because the visual acuity falls off in the visual periphery, we propose here to accelerate synthesizing hologram by differentiating density of point cloud projected on the screen. We classify the screen into multiple layers which are concentric circles with different radii, where the center is aligned with gaze of user. Layer with smaller radius is closer to the region of interest, hence, assigned with higher density of point cloud. Because the computation time is directly related to the number of points in point cloud, we can accelerate synthesizing hologram by lowering density of point cloud in the visual periphery. Cognitive study reveals that user cannot discriminate those degradation in the visual periphery if the parameters are properly designed. Prototype HHMD system will be provided for verifying the feasibility of our method, and detailed design scheme will be discussed.

  12. 3D holographic head mounted display using holographic optical elements with astigmatism aberration compensation.

    PubMed

    Yeom, Han-Ju; Kim, Hee-Jae; Kim, Seong-Bok; Zhang, HuiJun; Li, BoNi; Ji, Yeong-Min; Kim, Sang-Hoo; Park, Jae-Hyeung

    2015-12-14

    We propose a bar-type three-dimensional holographic head mounted display using two holographic optical elements. Conventional stereoscopic head mounted displays may suffer from eye fatigue because the images presented to each eye are two-dimensional ones, which causes mismatch between the accommodation and vergence responses of the eye. The proposed holographic head mounted display delivers three-dimensional holographic images to each eye, removing the eye fatigue problem. In this paper, we discuss the configuration of the bar-type waveguide head mounted displays and analyze the aberration caused by the non-symmetric diffraction angle of the holographic optical elements which are used as input and output couplers. Pre-distortion of the hologram is also proposed in the paper to compensate the aberration. The experimental results show that proposed head mounted display can present three-dimensional see-through holographic images to each eye with correct focus cues.

  13. "Head up and eyes out" advances in head mounted displays capabilities

    NASA Astrophysics Data System (ADS)

    Cameron, Alex

    2013-06-01

    There are a host of helmet and head mounted displays, flooding the market place with displays which provide what is essentially a mobile computer display. What sets aviators HMDs apart is that they provide the user with accurate conformal information embedded in the pilots real world view (see through display) where the information presented is intuitive and easy to use because it overlays the real world (mix of sensor imagery, symbolic information and synthetic imagery) and enables them to stay head up, eyes out, - improving their effectiveness, reducing workload and improving safety. Such systems are an enabling technology in the provision of enhanced Situation Awareness (SA) and reducing user workload in high intensity situations. Safety Is Key; so the addition of these HMD functions cannot detract from the aircrew protection functions of conventional aircrew helmets which also include life support and audio communications. These capabilities are finding much wider application in new types of compact man mounted audio/visual products enabled by the emergence of new families of micro displays, novel optical concepts and ultra-compact low power processing solutions. This papers attempts to capture the key drivers and needs for future head mounted systems for aviation applications.

  14. Performance considerations for high-definition head-mounted displays

    NASA Astrophysics Data System (ADS)

    Edwards, Oliver J.; Larimer, James O.; Gille, Jennifer

    1992-07-01

    We will discuss design image-optimization for helmet mounted displays (HMDs) in the context of a system engineering approach that includes a description of natural targets in the field, a description of perceptual characteristics of the human visual system, and device specifications that relate to these ecological and human-factors parameters that ultimately determine task performance. We will consider two HMD system as examples: the GEN III (AN/PVS-7A) night vision goggle (NVG) system and the SIPE helmet system (Soldier''s Integrated Protective Ensemble), both developed by S-TRON for use by the US Army.

  15. Head up and head mounted display performance improvements through advanced techniques in the manipulation of light

    NASA Astrophysics Data System (ADS)

    Wisely, Paul L.

    2009-05-01

    Since their introduction a number of years ago, head up and helmet mounted displays have undergone continuous and intensive development in aerospace applications. To date, the designs have been performed using geometric optic design techniques and have progressed to the point where very little further improvement in their characteristics is possible. This paper describes a display realised by the use of new optical design techniques based on wave-guiding principles that have enabled substantial further significant improvements to be made. These improvements are not only in respect of size, weight and volume for a given optical performance, but also in the optical characteristics that currently limit the usability of such displays in many applications. Displays that have been realised and tested through these methods are described and their performance in laboratory and flight trials discussed, together with considerations for further progress in their development.

  16. Comanche Helmet-Mounted Display Heading-Tape Simulation

    NASA Technical Reports Server (NTRS)

    Turpin, Terry; Dowell, Susan; Atencio, Adolph

    2006-01-01

    The Aeroflightdynamics Directorate (AMRDEC) conducted a simulation to assess the performance associated with a Contact Analog, world-referenced heading tape as implemented on the Comanche Helmet Integrated Display Sight System (HIDSS) when compared with a Compressed heading tape similar to that specified by the former Military Standard (MIL-STD) 1295. Six experienced pilots flew three modified Aeronautical Design Standards (ADS)-33 maneuvers (Hover Turn, Bob-up, Transient Turn) and a precision traffic pattern in the NASA Vertical Motion Simulator (VMS). Analysis of the pilot objective performance data and subjective handling qualities ratings (HQRs) showed the following: Compressed symbology in the Velocity Stabilization (VelStab) flight mode generally produced the most precise performances over Contact Analog symbology with respect to the heading, altitude, position, and time criteria specified for the maneuvers tested. VelStab outperformed the Automatic Flight Control System (AFCS) on all maneuvers achieving desired performance on most maneuvers for both symbol sets. Performance in the AFCS mode was generally desirable to adequate for heading and altitude and did not meet adequate standards for hover position and time for the Hover Turn and Bob-up maneuvers. VelStab and AFCS performance were nearly the same for the Transient Turn. Pilot comments concerning the Contact Analog heading-tape implementation were generally unfavorable in spite of the achieved levels of performance. HQRs showed Compressed symbology in the VelStab flight mode produced the lowest mean HQR, encompassing mixed ratings of satisfactory handling and needing improvement. All other symbology/flight-mode combinations yielded higher HQRs, which characterized opinions that deficiencies in aircraft handling due to HMD symbology would need improvement. Contact Analog heading tape and other symbology require improvement, especially when operating in the AFCS mode. NASA-TLX rated Compressed symbology

  17. Perceptual Issues in the Use of Head-Mounted Visual Displays

    DTIC Science & Technology

    2006-01-01

    Hakkinen (2004) reported similar problems when a monocular HMD was used during performance Perceptual Issues in the Use of Head-Mounted Visual Displays...person may miss information or signals while using an HMD. Hakkinen (2003) stated that monocular HMDs produce a common problem of rivalry and per- ceptual...mounted dis- plays. IEEE Transactions on Systems, Man, and Cybernetics, 24, 120–134. Hakkinen , J. (2003, September 9). Ergonomics of head-worn virtual

  18. Headphone and Head-Mounted Visual Displays for Virtual Environments

    NASA Technical Reports Server (NTRS)

    Begault, Duran R.; Ellis, Stephen R.; Wenzel, Elizabeth M.; Trejo, Leonard J. (Technical Monitor)

    1998-01-01

    A realistic auditory environment can contribute to both the overall subjective sense of presence in a virtual display, and to a quantitative metric predicting human performance. Here, the role of audio in a virtual display and the importance of auditory-visual interaction are examined. Conjectures are proposed regarding the effectiveness of audio compared to visual information for creating a sensation of immersion, the frame of reference within a virtual display, and the compensation of visual fidelity by supplying auditory information. Future areas of research are outlined for improving simulations of virtual visual and acoustic spaces. This paper will describe some of the intersensory phenomena that arise during operator interaction within combined visual and auditory virtual environments. Conjectures regarding audio-visual interaction will be proposed.

  19. Adoption of ASL Classifiers as Delivered by Head-Mounted Displays in a Planetarium Show

    ERIC Educational Resources Information Center

    Hintz, Eric G.; Jones, Michael D.; Lawler, M. Jeannette; Bench, Nathan; Mangrubang, Fred

    2015-01-01

    Accommodating the planetarium experience to members of the deaf or hard-of-hearing community has often created situations that are either disruptive to the rest of the audience or provide an insufficient accommodation. To address this issue, we examined the use of head-mounted displays to deliver an American Sign Language "sound track"…

  20. In the blink of an eye: head mounted displays development within BAE Systems

    NASA Astrophysics Data System (ADS)

    Cameron, Alex

    2015-05-01

    There has been an explosion of interest in head worn displays in recent years, particularly for consumer applications with an attendant ramping up of investment into key enabling technologies to provide what is essence a mobile computer display. However, head mounted system have been around for over 40 years and today's consumer products are building on a legacy of knowledge and technology created by companies such as BAE Systems who have been designing and fielding helmet mounted displays (HMD) for a wide range of specialist applications. Although the dominant application area has been military aviation, solutions have been fielded for solider, ground vehicle, simulation, medical, racing car and even subsea navigation applications. What sets these HMDs apart is that they provide the user with accurate conformal information embedded in the users real world view where the information presented is intuitive and easy to use because it overlays the real world and enables them to stay head up, eyes out, - improving their effectiveness, reducing workload and improving safety. Such systems are an enabling technology in the provision of enhanced Situation Awareness (SA) and reducing user workload in high intensity situations. These capabilities are finding much wider application in new types of compact man mounted audio/visual products enabled by the emergence of new families of micro displays, novel optical concepts and ultra-compact low power processing solutions. This paper therefore provides a personal summary of BAE Systems 40 year's journey in developing and fielding Head Mounted systems, their applications.

  1. A Novel Approach to Surgical Instructions for Scrub Nurses by Using See-Through-Type Head-Mounted Display.

    PubMed

    Yoshida, Soichiro; Sasaki, Asami; Sato, Chikage; Yamazaki, Mutsuko; Takayasu, Junya; Tanaka, Naofumi; Okabayashi, Norie; Hirano, Hiromi; Saito, Kazutaka; Fujii, Yasuhisa; Kihara, Kazunori

    2015-08-01

    In order to facilitate assists in surgical procedure, it is important for scrub nurses to understand the operation procedure and to share the operation status with attending surgeons. The potential utility of head-mounted display as a new imaging monitor has been proposed in the medical field. This study prospectively evaluated the usefulness of see-through-type head-mounted display as a novel intraoperative instructional tool for scrub nurses. From January to March 2014, scrub nurses who attended gasless laparoendoscopic single-port radical nephrectomy and radical prostatectomy wore the monocular see-through-type head-mounted display (AiRScouter; Brother Industries Ltd, Nagoya, Japan) displaying the instruction of the operation procedure through a crystal panel in front of the eye. Following the operation, the participants completed an anonymous questionnaire, which evaluated the image quality of the head-mounted display, the helpfulness of the head-mounted display to understand the operation procedure, and adverse effects caused by the head-mounted display. Fifteen nurses were eligible for the analysis. The intraoperative use of the head-mounted display could help scrub nurses to understand the surgical procedure and to hand out the instruments for the operation with no major head-mounted-display wear-related adverse event. This novel approach to support scrub nurses will help facilitate technical and nontechnical skills during surgery.

  2. Visual Issues In The Use Of A Head-Mounted Monocular Display

    NASA Astrophysics Data System (ADS)

    Peli, Eli

    1989-11-01

    A miniature display device, recently available commercially, is aimed at providing a portable, inexpensive means of visual information communication. The display is head-mounted in front of one eye with the other eye's view of the environment unobstructed. Various visual phenomena are associated with this design. The consequences of these phenomena for visual safety, comfort, and efficiency of the user were evaluated: (1) The monocular, partially occluded mode of operation interrupts binocular vision. Presenting disparate images to each eye results in binocular rivalry. The two images may appear superimposed, with one image perceived with greater clarity or com letely dominant. Most observers can, use the display comfortably in this rivalrous mode. In many cases, it is easier to use the display in a peripheral position, slightly above or below the line of sight, thus permitting normal binocular vision of the environment. (2) As a head-mounted device, the displayed image is perceived to move during head movements due to the response of the vestibulo-ocular reflex. These movements affect the visibility of small letters during active head rotations and sharp accelerations. Adaptation is likely to reduce this perceived image motion. No evidence for postural instability or motion sickness was noted as a result of these conflicts between vis-ual and vestibular inputs. (3) Small displacements of the image are noted even without head motion, resulting from eye movements and the virtual lack of display persiste ce. These movements are noticed sponta e ously by few observers and are unlikely to interfere with the display use in most tasks.

  3. An Evaluation of Signal Annoyance for a Head-Mounted Tactile Display

    DTIC Science & Technology

    2015-03-01

    An Evaluation of Signal Annoyance for a Head-Mounted Tactile Display Kimberly Myles and Joel T Kalb Human Research and Engineering Directorate...tissue in the skull , but the transducer would also be capable of transmitting vibration to the skin. The BC system would allow Soldiers to...communications. Proceedings of the Human Factors and Ergonomics Society 50th Annual Meeting; 2006 Oct 16–20; San Francisco, CA. Thousand Oaks (CA): SAGE

  4. Optical waveguide technology and its application in head-mounted displays

    NASA Astrophysics Data System (ADS)

    Cameron, Alex

    2012-06-01

    Applying optical waveguide technology to head mounted display (HMD) solutions has the key goal of providing the user with improved tactical situational awareness by providing information and imagery in an easy to use form which also maintains compatibility with current night vision devices and also enables the integration of future night vision devices. The benefits of waveguide technology in HMDs have seen a number of alternative waveguide display technologies and configurations emerge for Head mounted Display applications. BAE System's presented one such technology in 2009 [1] and this is now in production for a range of Helmet Mounted Display products. This paper outlines the key design drivers for aviators Helmet Mounted Displays, provides an update of holographic Optical Waveguide Technology and its maturation into compact, lightweight Helmet Mounted Displays products for aviation and non-aviation applications. Waveguide displays have proved too be a radical enabling technology which allows higher performance display devices solutions to be created in a revolutionary way. It has also provided the user with see through daylight readable displays, offering the combination of very large eye box and excellent real world transmission in a compact format. Holographic Optical Waveguide is an optical technology which reduces size and mass whilst liberating the designer from many of the constraints inherent in conventional optical solutions. This technology is basically a way of moving light without the need for a complex arrangement of conventional lenses. BAE Systems has exploited this technology in the Q-SightTM family of scalable Helmet Mounted Displays; allowing the addition of capability as it is required in a flexible, low-cost way The basic monocular Q-SightTM architecture has been extended to offer wide field of view, monochrome and full colour HMD solution for rotary wing, fast jet and solider system applications. In its basic form Q-SightTM now offers plug

  5. A see-through holographic head-mounted display with the large viewing angle

    NASA Astrophysics Data System (ADS)

    Chen, Zhidong; sang, Xinzhu; Lin, Qiaojun; Li, Jin; Yu, Xunbo; Gao, Xin; Yan, Binbin; Wang, Kuiru; Yu, Chongxiu; Xie, Songlin

    2017-02-01

    A novel solution for the large view angle holographic head-mounted display (HHMD) is presented. Divergent light is used for the hologram illumination to construct a large size three-dimensional object outside the display in a short distance. A designed project-type lens with large numerical aperture projects the object constructed by the hologram to its real location. The presented solution can realize a compact HHMD system with a large field of view. The basic principle and the structure of the system are described. An augmented reality (AR) prototype with the size of 50 mm×40 mm and the view angle above 60° is demonstrated.

  6. Monocular 3D see-through head-mounted display via complex amplitude modulation.

    PubMed

    Gao, Qiankun; Liu, Juan; Han, Jian; Li, Xin

    2016-07-25

    The complex amplitude modulation (CAM) technique is applied to the design of the monocular three-dimensional see-through head-mounted display (3D-STHMD) for the first time. Two amplitude holograms are obtained by analytically dividing the wavefront of the 3D object to the real and the imaginary distributions, and then double amplitude-only spatial light modulators (A-SLMs) are employed to reconstruct the 3D images in real-time. Since the CAM technique can inherently present true 3D images to the human eye, the designed CAM-STHMD system avoids the accommodation-convergence conflict of the conventional stereoscopic see-through displays. The optical experiments further demonstrated that the proposed system has continuous and wide depth cues, which enables the observer free of eye fatigue problem. The dynamic display ability is also tested in the experiments and the results showed the possibility of true 3D interactive display.

  7. Analysis of a head-mounted display-type multifocus display system using a laser scanning method

    NASA Astrophysics Data System (ADS)

    Kim, Dong-Wook; Kwon, Yong-Moo; Park, Q.-Han; Kim, Sung-Kyu

    2011-03-01

    We developed a head-mounted display (HMD)-type multifocus display system using a laser-scanning method to provide an accommodation effect for viewers. This accomplishment indicates that providing a monocular depth cue is possible through this multifocus system. In the system, the optical path is changed by a scanning action. To provide an accurate accommodation effect for the viewer, the multifocus display system is designed and manufactured in accordance with the geometric analysis of the system's scanning action. Using a video camera as a substitute for the viewer, correct focus adjustment without the scanning action problem is demonstrated. By analyzing the scanning action and experimental results, we are able to illustrate the formation of a viewpoint in an HMD-type multifocus display system using a laser-scanning method. In addition, we demonstrate that the accommodation effect could be provided independent of the viewing condition of the viewer.

  8. Hybrid diffractive-refractive optical system design of head-mounted display for augmented reality

    NASA Astrophysics Data System (ADS)

    Zhang, Huijuan

    2005-02-01

    An optical see-through head-mounted display for augmented reality is designed in this paper. Considering the factors, such as the optical performance, the utilization ratios of energy of real world and virtual world, the feelings of users when he wears it and etc., a structure of the optical see-through is adopted. With the characteristics of the particular negative dispersive and the power of realizing random-phase modulation, the diffractive surface is helpful for optical system of reducing weight, simplifying structure and etc., and a diffractive surface is introduced in our optical system. The optical system with 25 mm eye relief, 12 mm exit pupil and 20° (H)x15.4° (V) field-of-view is designed. The utilization ratios of energy of real world and virtual world are 1/4 and 1/2, respectively. The angular resolution of display is 0.27 mrad and it less than that of the minimum of human eyes. The diameter of this system is less than 46mm, and it applies the binocular. This diffractive-refractive optical system of see-through head-mounted display not only satisfies the demands of user"s factors in structure, but also with high resolution, very small chromatic aberration and distortion, and satisfies the need of augmented reality. In the end, the parameters of the diffractive surface are discussed.

  9. Quantitative assessment of visual acuity in projective head-mounted displays

    NASA Astrophysics Data System (ADS)

    Fidopiastis, Cali M.; Meyer, Catherine; Fuhrman, Christopher A.; Rolland, Jannick P.

    2003-09-01

    One issue of head mounted display design relates to the tradeoff between field of view (FOV) and resolution, which can lead to reduced visual acuity (VA). Essentially, an increase in FOV causes a decrease in visual acuity, for a given LCD display that has a fixed number of pixels. The effects of enhanced brightness on VA using two different types of retro-reflective material (cubed or beaded) were tested using a 52 deg. FOV projective helmet mounted display with VGA resolution. Three lighting conditions were also tested. Based on the display size, resolution, and FOV, we estimated a maximum visual acuity of 4.1 minutes of arc. In a counter-balanced between measures design, subjects' psychometric acuity functions were determined using a computer-generated 4AFC Landolt C test presented stereoscopically and probit analysis. The results confirmed that the maximum visual acuity possible within the setup was 4.1 arc minutes, the limit imposed by the microdisplay, and not the retroreflective material.

  10. A head-mounted compressive three-dimensional display system with polarization-dependent focus switching

    NASA Astrophysics Data System (ADS)

    Lee, Chang-Kun; Moon, Seokil; Lee, Byounghyo; Jeong, Youngmo; Lee, Byoungho

    2016-10-01

    A head-mounted compressive three-dimensional (3D) display system is proposed by combining polarization beam splitter (PBS), fast switching polarization rotator and micro display with high pixel density. According to the polarization state of the image controlled by polarization rotator, optical path of image in the PBS can be divided into transmitted and reflected components. Since optical paths of each image are spatially separated, it is possible to independently focus both images at different depth positions. Transmitted p-polarized and reflected s-polarized images can be focused by convex lens and mirror, respectively. When the focal lengths of the convex lens and mirror are properly determined, two image planes can be located in intended positions. The geometrical relationship is easily modulated by replacement of the components. The fast switching of polarization realizes the real-time operation of multi-focal image planes with a single display panel. Since it is possible to conserve the device characteristic of single panel, the high image quality, reliability and uniformity can be retained. For generating 3D images, layer images for compressive light field display between two image planes are calculated. Since the display panel with high pixel density is adopted, high quality 3D images are reconstructed. In addition, image degradation by diffraction between physically stacked display panels can be mitigated. Simple optical configuration of the proposed system is implemented and the feasibility of the proposed method is verified through experiments.

  11. A 3D integral imaging optical see-through head-mounted display.

    PubMed

    Hua, Hong; Javidi, Bahram

    2014-06-02

    An optical see-through head-mounted display (OST-HMD), which enables optical superposition of digital information onto the direct view of the physical world and maintains see-through vision to the real world, is a vital component in an augmented reality (AR) system. A key limitation of the state-of-the-art OST-HMD technology is the well-known accommodation-convergence mismatch problem caused by the fact that the image source in most of the existing AR displays is a 2D flat surface located at a fixed distance from the eye. In this paper, we present an innovative approach to OST-HMD designs by combining the recent advancement of freeform optical technology and microscopic integral imaging (micro-InI) method. A micro-InI unit creates a 3D image source for HMD viewing optics, instead of a typical 2D display surface, by reconstructing a miniature 3D scene from a large number of perspective images of the scene. By taking advantage of the emerging freeform optical technology, our approach will result in compact, lightweight, goggle-style AR display that is potentially less vulnerable to the accommodation-convergence discrepancy problem and visual fatigue. A proof-of-concept prototype system is demonstrated, which offers a goggle-like compact form factor, non-obstructive see-through field of view, and true 3D virtual display.

  12. Passive method of eliminating accommodation/convergence disparity in stereoscopic head-mounted displays

    NASA Astrophysics Data System (ADS)

    Eichenlaub, Jesse B.

    2005-03-01

    The difference in accommodation and convergence distance experienced when viewing stereoscopic displays has long been recognized as a source of visual discomfort. It is especially problematic in head mounted virtual reality and enhanced reality displays, where images must often be displayed across a large depth range or superimposed on real objects. DTI has demonstrated a novel method of creating stereoscopic images in which the focus and fixation distances are closely matched for all parts of the scene from close distances to infinity. The method is passive in the sense that it does not rely on eye tracking, moving parts, variable focus optics, vibrating optics, or feedback loops. The method uses a rapidly changing illumination pattern in combination with a high speed microdisplay to create cones of light that converge at different distances to form the voxels of a high resolution space filling image. A bench model display was built and a series of visual tests were performed in order to demonstrate the concept and investigate both its capabilities and limitations. Results proved conclusively that real optical images were being formed and that observers had to change their focus to read text or see objects at different distances

  13. Eyetracked optical see-through head-mounted display as an AAC device

    NASA Astrophysics Data System (ADS)

    Hua, Hong; Hu, Xinda; Gao, Chunyu; Qin, Xiao

    2014-06-01

    An eye-tracked head-mounted display (ET-HMD) system is able to display virtual images as a classical headmounted display (HMD) does, while additionally tracking the gaze direction of the user. An HMD with fullyintegrated eyetracking capability offers multi-fold benefits, not only to fundamental scientific research but also to emerging applications of such technology. A key limitation of the state-of-the-art ET-HMD technology is the lack of compactness and portability. In this paper, we present an innovative design of a high resolution optical see-through ET-HMD system based on freeform optical technology. A prototype system is demonstrated, which offers a goggle-like compact form factor, non-obstructive see-through field of view, true high-definition image resolution for the virtual display, and better than 0.5 arc minute of angular resolution for the see-through view. We will demonstrate the application of the technology as an assistive and augmentative communication (AAC) device.

  14. Alternate optical designs for head-mounted displays with a wide field of view.

    PubMed

    Chen, Bo; Herkommer, Alois M

    2017-02-01

    The most widely applied design form for mixed reality head-mounted display (HMD) systems is generally a prism with one surface in total internal reflection (TIR). This, however, limits the angle of the incident rays, and thus decreases the design freedom and affects the performance. To obtain better performance of the HMD optics, in this paper two seldom used design forms of HMD systems are presented and compared to the standard TIR HMD optics. One of them is a catadioptric HMD system, consisting of one lens and two mirrors; the other is a prism HMD with a different folding geometry. The designs are compared for a field of view of 40°×30°; however, they are also investigated for an increased field of view of 50°×30°. The evaluation indicates good performance of our systems. In particular, the prism with an alternate folding geometry has advantages in both performance and size.

  15. Comparing two input devices for virtual walkthroughs using a Head Mounted Display (HMD)

    NASA Astrophysics Data System (ADS)

    Sousa Santos, Beatriz; Dias, Paulo; Santos, Paulo; Ferreira, Carlos

    2014-02-01

    Selecting input and output devices to be used in virtual walkthroughs is an important issue as it may have significant impact in usability and comfort. This paper presents a user study meant to compare the usability of two input devices used for walkthroughs in a virtual environment with a Head-Mounted Display. User performance, satisfaction, ease of use and comfort, were compared with two different input devices: a two button mouse and a joystick from a gamepad. Participants also used a desktop to perform the same tasks in order to assess if the participant groups had similar profiles. The results obtained by 45 participants suggest that both input devices have a comparable usability in the used conditions and show that participants generally performed better with the desktop; a discussion of possible causes is presented.

  16. Continued Testing of Head-Mounted Displays for Deaf Education in a Planetarium

    NASA Astrophysics Data System (ADS)

    Hintz, Eric G.; Jones, M.; Lawler, J.; Bench, N.; Mangrubang, F. R.

    2013-06-01

    For more than a year now we have been developing techniques for using Head-Mounted Displays (HMD) to help accommodate a deaf audience in a planetarium environment. Our target audience is primarily children from 8 to 13 years of age, but the methodologies can be used for a wide variety of audiences. Applications also extend beyond the planetarium environment. Three tests have been done to determine if American Sign Language (ASL) can be delivered to the HMD and the student view both the planetarium show and the ASL ‘sound track’. From those early results we are now at the point of testing for comprehension improvement on a number of astronomical subjects. We will present a number of these early results.

  17. Optical gesture sensing and depth mapping technologies for head-mounted displays: an overview

    NASA Astrophysics Data System (ADS)

    Kress, Bernard; Lee, Johnny

    2013-05-01

    Head Mounted Displays (HMDs), and especially see-through HMDs have gained renewed interest in recent time, and for the first time outside the traditional military and defense realm, due to several high profile consumer electronics companies presenting their products to hit market. Consumer electronics HMDs have quite different requirements and constrains as their military counterparts. Voice comments are the de-facto interface for such devices, but when the voice recognition does not work (not connection to the cloud for example), trackpad and gesture sensing technologies have to be used to communicate information to the device. We review in this paper the various technologies developed today integrating optical gesture sensing in a small footprint, as well as the various related 3d depth mapping sensors.

  18. Video-based eyetracking methods and algorithms in head-mounted displays

    NASA Astrophysics Data System (ADS)

    Hua, Hong; Krishnaswamy, Prasanna; Rolland, Jannick P.

    2006-05-01

    Head pose is utilized to approximate a user’s line-of-sight for real-time image rendering and interaction in most of the 3D visualization applications using head-mounted displays (HMD). The eye often reaches an object of interest before the completion of most head movements. It is highly desirable to integrate eye-tracking capability into HMDs in various applications. While the added complexity of an eyetracked-HMD (ET-HMD) imposes challenges on designing a compact, portable, and robust system, the integration offers opportunities to improve eye tracking accuracy and robustness. In this paper, based on the modeling of an eye imaging and tracking system, we examine the challenges and identify parametric requirements for video-based pupil-glint tracking methods in an ET-HMD design, and predict how these parameters may affect the tracking accuracy, resolution, and robustness. We further present novel methods and associated algorithms that effectively improve eye-tracking accuracy and extend the tracking range.

  19. Immersive Collaborative Analysis of Network Connectivity: CAVE-style or Head-Mounted Display?

    PubMed

    Cordeil, Maxime; Dwyer, Tim; Klein, Karsten; Laha, Bireswar; Marriott, Kim; Thomas, Bruce H

    2017-01-01

    High-quality immersive display technologies are becoming mainstream with the release of head-mounted displays (HMDs) such as the Oculus Rift. These devices potentially represent an affordable alternative to the more traditional, centralised CAVE-style immersive environments. One driver for the development of CAVE-style immersive environments has been collaborative sense-making. Despite this, there has been little research on the effectiveness of collaborative visualisation in CAVE-style facilities, especially with respect to abstract data visualisation tasks. Indeed, very few studies have focused on the use of these displays to explore and analyse abstract data such as networks and there have been no formal user studies investigating collaborative visualisation of abstract data in immersive environments. In this paper we present the results of the first such study. It explores the relative merits of HMD and CAVE-style immersive environments for collaborative analysis of network connectivity, a common and important task involving abstract data. We find significant differences between the two conditions in task completion time and the physical movements of the participants within the space: participants using the HMD were faster while the CAVE2 condition introduced an asymmetry in movement between collaborators. Otherwise, affordances for collaborative data analysis offered by the low-cost HMD condition were not found to be different for accuracy and communication with the CAVE2. These results are notable, given that the latest HMDs will soon be accessible (in terms of cost and potentially ubiquity) to a massive audience.

  20. Semi-parametric color reproduction method for optical see-through head-mounted displays.

    PubMed

    Itoh, Yuta; Dzitsiuk, Maksym; Amano, Toshiyuki; Klinker, Gudrun

    2015-11-01

    The fundamental issues in Augmented Reality (AR) are on how to naturally mediate the reality with virtual content as seen by users. In AR applications with Optical See-Through Head-Mounted Displays (OST-HMD), the issues often raise the problem of rendering color on the OST-HMD consistently to input colors. However, due to various display constraints and eye properties, it is still a challenging task to indistinguishably reproduce the colors on OST-HMDs. An approach to solve this problem is to pre-process the input color so that a user perceives the output color on the display to be the same as the input. We propose a color calibration method for OST-HMDs. We start from modeling the physical optics in the rendering and perception process between the HMD and the eye. We treat the color distortion as a semi-parametric model which separates the non-linear color distortion and the linear color shift. We demonstrate that calibrated images regain their original appearance on two OST-HMD setups with both synthetic and real datasets. Furthermore, we analyze the limitations of the proposed method and remaining problems of the color reproduction in OST-HMDs. We then discuss how to realize more practical color reproduction methods for future HMD-eye system.

  1. The virtual reality head-mounted display Oculus Rift induces motion sickness and is sexist in its effects.

    PubMed

    Munafo, Justin; Diedrick, Meg; Stoffregen, Thomas A

    2017-03-01

    Anecdotal reports suggest that motion sickness may occur among users of contemporary, consumer-oriented head-mounted display systems and that women may be at greater risk. We evaluated the nauseogenic properties of one such system, the Oculus Rift. The head-mounted unit included motion sensors that were sensitive to users' head movements, such that head movements could be used as control inputs to the device. In two experiments, seated participants played one of two virtual reality games for up to 15 min. In Experiment 1, 22% of participants reported motion sickness, and the difference in incidence between men and women was not significant. In Experiment 2, motion sickness was reported by 56% of participants, and incidence among women (77.78%) was significantly greater than among men (33.33%). Before participants were exposed to the head-mounted display system, we recorded their standing body sway during the performance of simple visual tasks. In both experiments, patterns of pre-exposure body sway differed between participants who (later) reported motion sickness and those who did not. In Experiment 2, sex differences in susceptibility to motion sickness were preceded by sex differences in body sway. These postural effects confirm a prediction of the postural instability theory of motion sickness. The results indicate that users of contemporary head-mounted display systems are at significant risk of motion sickness and that in relation to motion sickness these systems may be sexist in their effects.

  2. Visual task performance using a monocular see-through head-mounted display (HMD) while walking.

    PubMed

    Mustonen, Terhi; Berg, Mikko; Kaistinen, Jyrki; Kawai, Takashi; Häkkinen, Jukka

    2013-12-01

    A monocular see-through head-mounted display (HMD) allows the user to view displayed information while simultaneously interacting with the surrounding environment. This configuration lets people use HMDs while they are moving, such as while walking. However, sharing attention between the display and environment can compromise a person's performance in any ongoing task, and controlling one's gait may add further challenges. In this study, the authors investigated how the requirements of HMD-administered visual tasks altered users' performance while they were walking. Twenty-four university students completed 3 cognitive tasks (high- and low-working memory load, visual vigilance) on an HMD while seated and while simultaneously performing a paced walking task in a controlled environment. The results show that paced walking worsened performance (d', reaction time) in all HMD-administered tasks, but visual vigilance deteriorated more than memory performance. The HMD-administered tasks also worsened walking performance (speed, path overruns) in a manner that varied according to the overall demands of the task. These results suggest that people's ability to process information displayed on an HMD may worsen while they are in motion. Furthermore, the use of an HMD can critically alter a person's natural performance, such as their ability to guide and control their gait. In particular, visual tasks that involve constant monitoring of the HMD should be avoided. These findings highlight the need for careful consideration of the type and difficulty of information that can be presented through HMDs while still letting the user achieve an acceptable overall level of performance in various contexts of use.

  3. Compact three-dimensional head-mounted display system with Savart plate.

    PubMed

    Lee, Chang-Kun; Moon, Seokil; Lee, Seungjae; Yoo, Dongheon; Hong, Jong-Young; Lee, Byoungho

    2016-08-22

    We propose three-dimensional (3D) head-mounted display (HMD) providing multi-focal and wearable functions by using polarization-dependent optical path switching in Savart plate. The multi-focal function is implemented as micro display with high pixel density of 1666 pixels per inches is optically duplicated in longitudinal direction according to the polarization state. The combination of micro display, fast switching polarization rotator and Savart plate retains small form factor suitable for wearable function. The optical aberrations of duplicated panels are investigated by ray tracing according to both wavelength and polarization state. Astigmatism and lateral chromatic aberration of extraordinary wave are compensated by modification of the Savart plate and sub-pixel shifting method, respectively. To verify the feasibility of the proposed system, a prototype of the HMD module for monocular eye is implemented. The module has the compact size of 40 mm by 90 mm by 40 mm and the weight of 131 g with wearable function. The micro display and polarization rotator are synchronized in real-time as 30 Hz and two focal planes are formed at 640 and 900 mm away from eye box, respectively. In experiments, the prototype also provides augmented reality function by combining the optically duplicated panels with a beam splitter. The multi-focal function of the optically duplicated panels without astigmatism and color dispersion compensation is verified. When light field optimization for two additive layers is performed, perspective images are observed, and the integration of real world scene and high quality 3D images is confirmed.

  4. Rapid P300 brain-computer interface communication with a head-mounted display

    PubMed Central

    Käthner, Ivo; Kübler, Andrea; Halder, Sebastian

    2015-01-01

    Visual ERP (P300) based brain-computer interfaces (BCIs) allow for fast and reliable spelling and are intended as a muscle-independent communication channel for people with severe paralysis. However, they require the presentation of visual stimuli in the field of view of the user. A head-mounted display could allow convenient presentation of visual stimuli in situations, where mounting a conventional monitor might be difficult or not feasible (e.g., at a patient's bedside). To explore if similar accuracies can be achieved with a virtual reality (VR) headset compared to a conventional flat screen monitor, we conducted an experiment with 18 healthy participants. We also evaluated it with a person in the locked-in state (LIS) to verify that usage of the headset is possible for a severely paralyzed person. Healthy participants performed online spelling with three different display methods. In one condition a 5 × 5 letter matrix was presented on a conventional 22 inch TFT monitor. Two configurations of the VR headset were tested. In the first (glasses A), the same 5 × 5 matrix filled the field of view of the user. In the second (glasses B), single letters of the matrix filled the field of view of the user. The participant in the LIS tested the VR headset on three different occasions (glasses A condition only). For healthy participants, average online spelling accuracies were 94% (15.5 bits/min) using three flash sequences for spelling with the monitor and glasses A and 96% (16.2 bits/min) with glasses B. In one session, the participant in the LIS reached an online spelling accuracy of 100% (10 bits/min) using the glasses A condition. We also demonstrated that spelling with one flash sequence is possible with the VR headset for healthy users (mean: 32.1 bits/min, maximum reached by one user: 71.89 bits/min at 100% accuracy). We conclude that the VR headset allows for rapid P300 BCI communication in healthy users and may be a suitable display option for severely

  5. Binocular Convergence and Errors in Judged Distance While Using Head-mounted See-through Displays

    NASA Technical Reports Server (NTRS)

    Ellis, Stephen R.; Bucher, Urs J.; Menges, Brian M.; Null, Cynthia H. (Technical Monitor)

    1995-01-01

    Previous observations have shown that optical superposition of a physical backdrops at the judged depth of a stereoscopic virtual image moves the judged depth closer to the observer. This effect was more pronounced for slowly moving physical backdrops and was not enhanced when the virtual image was rendered as a flat shaded solid object rather than a open wire-frame. Since this change in rendering making the virtual image more completely occlude the backdrop did not effect its judged depth and since the motion of the backdrop which would have attracted visual attention and binocular convergence did Increase its perceptual displacement, it was concluded that the change In Judged depth was not due to the perceived occlusion. Rather it was concluded to be due to an increase in binocular convergence. An experimental test of this hypothesis using a unobtrusive nonius technique to detect absolute and relative convergence has confirmed the presence of convergence correlated with the magnitude of the change in judged position of this virtual Image. The practical implications of this cause are demonstrated by a second study using monocular, biocular and stereoscopic viewing conditions and the consequences for the design of head-mounted see-through displays for near work are discussed.

  6. Contribution of TopOwl head mounted display system in degraded visual environments

    NASA Astrophysics Data System (ADS)

    Lemoine, Olivier; François, Jean-Michel; Point, Pascal

    2013-05-01

    Piloting a rotorcraft in a Degraded Visual Environment (DVE) is a very complex task, and the evolution of the rotorcraft missions tend to augment the probability of such degraded flight conditions (increase of night flights, all-weather flights, with brownout or whiteout phenomena…). When the direct view of the external situation is degraded, the avionic system can be of great help for the crew to recover the lost visual references. TopOwl® Head Mounted Sight and Display (HMSD) system is particularly adapted to such situations, allowing the pilot to remain "eyes-out" while visualizing on a large field of view different information: a conformal enhanced image (EVS) coming from an on-board sensor, various 2D and 3D symbologies (flight, navigation, mission specific symbols), a conformal synthetic representation of the terrain (SVS), a night vision image coming from the integrated Image Intensifier Tubes, or a combination of these data, depending on the external conditions and the phase of flight, according to the pilot's choice.

  7. Recognition of American Sign Language (ASL) Classifiers in a Planetarium Using a Head-Mounted Display

    NASA Astrophysics Data System (ADS)

    Hintz, Eric G.; Jones, Michael; Lawler, Jeannette; Bench, Nathan

    2015-01-01

    A traditional accommodation for the deaf or hard-of-hearing in a planetarium show is some type of captioning system or a signer on the floor. Both of these have significant drawbacks given the nature of a planetarium show. Young audience members who are deaf likely don't have the reading skills needed to make a captioning system effective. A signer on the floor requires light which can then splash onto the dome. We have examined the potential of using a Head-Mounted Display (HMD) to provide an American Sign Language (ASL) translation. Our preliminary test used a canned planetarium show with a pre-recorded sound track. Since many astronomical objects don't have official ASL signs, the signer had to use classifiers to describe the different objects. Since these are not official signs, these classifiers provided a way to test to see if students were picking up the information using the HMD.We will present results that demonstrate that the use of HMDs is at least as effective as projecting a signer on the dome. This also showed that the HMD could provide the necessary accommodation for students for whom captioning was ineffective. We will also discuss the current effort to provide a live signer without the light splash effect and our early results on teaching effectiveness with HMDs.This work is partially supported by funding from the National Science Foundation grant IIS-1124548 and the Sorenson Foundation.

  8. Application of virtual reality head mounted display for investigation of movement: a novel effect of orientation of attention

    NASA Astrophysics Data System (ADS)

    Quinlivan, Brendan; Butler, John S.; Beiser, Ines; Williams, Laura; McGovern, Eavan; O'Riordan, Sean; Hutchinson, Michael; Reilly, Richard B.

    2016-10-01

    Objective. To date human kinematics research has relied on video processing, motion capture and magnetic search coil data acquisition techniques. However, the use of head mounted display virtual reality systems, as a novel research tool, could facilitate novel studies into human movement and movement disorders. These systems have the unique ability of presenting immersive 3D stimulus while also allowing participants to make ecologically valid movement-based responses. Approach. We employed one such system (Oculus Rift DK2) in this study to present visual stimulus and acquire head-turn data from a cohort of 40 healthy adults. Participants were asked to complete head movements towards eccentrically located visual targets following valid and invalid cues. Such tasks are commonly employed for investigating the effects orientation of attention and are known as Posner cueing paradigms. Electrooculography was also recorded for a subset of 18 participants. Main results. A delay was observed in onset of head movement and saccade onset during invalid trials, both at the group and single participant level. We found that participants initiated head turns 57.4 ms earlier during valid trials. A strong relationship between saccade onset and head movement onset was also observed during valid trials. Significance. This work represents the first time that the Posner cueing effect has been observed in onset of head movement in humans. The results presented here highlight the role of head-mounted display systems as a novel and practical research tool for investigations of normal and abnormal movement patterns.

  9. Cybersickness provoked by head-mounted display affects cutaneous vascular tone, heart rate and reaction time.

    PubMed

    Nalivaiko, Eugene; Davis, Simon L; Blackmore, Karen L; Vakulin, Andrew; Nesbitt, Keith V

    2015-11-01

    Evidence from studies of provocative motion indicates that motion sickness is tightly linked to the disturbances of thermoregulation. The major aim of the current study was to determine whether provocative visual stimuli (immersion into the virtual reality simulating rides on a rollercoaster) affect skin temperature that reflects thermoregulatory cutaneous responses, and to test whether such stimuli alter cognitive functions. In 26 healthy young volunteers wearing head-mounted display (Oculus Rift), simulated rides consistently provoked vection and nausea, with a significant difference between the two versions of simulation software (Parrot Coaster and Helix). Basal finger temperature had bimodal distribution, with low-temperature group (n=8) having values of 23-29 °C, and high-temperature group (n=18) having values of 32-36 °C. Effects of cybersickness on finger temperature depended on the basal level of this variable: in subjects from former group it raised by 3-4 °C, while in most subjects from the latter group it either did not change or transiently reduced by 1.5-2 °C. There was no correlation between the magnitude of changes in the finger temperature and nausea score at the end of simulated ride. Provocative visual stimulation caused prolongation of simple reaction time by 20-50 ms; this increase closely correlated with the subjective rating of nausea. Lastly, in subjects who experienced pronounced nausea, heart rate was elevated. We conclude that cybersickness is associated with changes in cutaneous thermoregulatory vascular tone; this further supports the idea of a tight link between motion sickness and thermoregulation. Cybersickness-induced prolongation of reaction time raises obvious concerns regarding the safety of this technology.

  10. Visibility of Monocular Symbology in Transparent Head-Mounted Display Applications

    DTIC Science & Technology

    2015-07-08

    information with binocular parallax (also called binocular disparity, the cue for stereoscopic depth perception ) is presented to two eyes, it is called...33. Winterbottom, M. et al. Operational Based Vision Assessment Resarch: Depth Perception . J. Australas. Soc. Aerosp. Med. 9, 33–41 (2014). 34...Publishers, 1998). 4. Bayer, M., Rash, E. & Brindle, J. in Helmet-Mounted Displays: Sensation, Perception , and Cognition Issues (eds. Rash, C

  11. Visual cueing considerations in Nap-of-the-Earth helicopter flight head-slaved helmet-mounted displays

    NASA Technical Reports Server (NTRS)

    Grunwald, Arthur J.; Kohn, Silvia

    1993-01-01

    The pilot's ability to derive Control-Oriented Visual Field Information from teleoperated Helmet-Mounted displays in Nap-of-the-Earth flight, is investigated. The visual field with these types of displays, commonly used in Apache and Cobra helicopter night operations, originates from a relatively narrow field-of-view Forward Looking Infrared Radiation Camera, gimbal-mounted at the nose of the aircraft and slaved to the pilot's line-of-sight, in order to obtain a wide-angle field-of-regard. Pilots have encountered considerable difficulties in controlling the aircraft by these devices. Experimental simulator results presented here indicate that part of these difficulties can be attributed to head/camera slaving system phase lags and errors. In the presence of voluntary head rotation, these slaving system imperfections are shown to impair the Control-Oriented Visual Field Information vital in vehicular control, such as the perception of the anticipated flight path or the vehicle yaw rate. Since, in the presence of slaving system imperfections, the pilot will tend to minimize head rotation, the full wide-angle field-of-regard of the line-of-sight slaved Helmet-Mounted Display, is not always fully utilized.

  12. EMU helmet mounted display

    NASA Technical Reports Server (NTRS)

    Marmolejo, Jose (Inventor); Smith, Stephen (Inventor); Plough, Alan (Inventor); Clarke, Robert (Inventor); Mclean, William (Inventor); Fournier, Joseph (Inventor)

    1990-01-01

    A helmet mounted display device is disclosed for projecting a display on a flat combiner surface located above the line of sight where the display is produced by two independent optical channels with independent LCD image generators. The display has a fully overlapped field of view on the combiner surface and the focus can be adjusted from a near field of four feet to infinity.

  13. Investigation of a 3D head-mounted projection display using retro-reflective screen.

    PubMed

    Héricz, Dalma; Sarkadi, Tamás; Lucza, Viktor; Kovács, Viktor; Koppa, Pál

    2014-07-28

    We propose a compact head-worn 3D display which provides glasses-free full motion parallax. Two picoprojectors placed on the viewer's head project images on a retro-reflective screen that reflects left and right images to the appropriate eyes of the viewer. The properties of different retro-reflective screen materials have been investigated, and the key parameters of the projection - brightness and cross-talk - have been calculated. A demonstration system comprising two projectors, a screen tracking system and a commercial retro-reflective screen has been developed to test the visual quality of the proposed approach.

  14. Integrated image monitoring system using head-mounted display for gasless single-port clampless partial nephrectomy.

    PubMed

    Kihara, Kazunori; Saito, Kazutaka; Komai, Yoshinobu; Fujii, Yasuhisa

    2014-12-01

    A novel head-mounted display (HMD) offers a higher quality of endoscopic imagery in front of the eyes regardless of head position. We present an application of the HMD system as a personal integrated multi-image monitoring system in gasless single-port clampless partial nephrectomy (PN). Our HMD system displayed multiple forms of information as integrated, sharp, high-contrast images both seamlessly and synchronously using a four-split screen. The surgeon wearing an HMD display could continuously and simultaneously monitor the endoscopic, three-dimensional (3D) video and intraoperative ultrasound images. In addition, the operator can rotate the 3D video image using fingertip movements on the finger tracking system. All two clampless partial nephrectomies were safely completed within the operative time, blood loss was within usual limits and there were no complications. The integrated image HMD system might facilitate maneuverability and safety in minimally invasive clampless PN.

  15. Lightweight high-brightness helmet-mounted head-up display system

    NASA Astrophysics Data System (ADS)

    Wagner, Mathieu; North, Thibault; Bourquin, Stéphane; Kilcher, Lucio

    2016-03-01

    We present a compact binocular head-up display for integration in a motorcycle helmet. A 2D MEMS-mirror reflecting laser beams enables the formation of a bright image superimposed on the user vision by means of retinal scanning. A 3d-printed prototype including the required optical components is presented and characterized. It fits the morphology of most users thanks to several degrees of freedom accessible to the user for fine-tuning.

  16. Wireless communication technology as applied to head mounted display for a tactical fighter pilot

    NASA Astrophysics Data System (ADS)

    Saini, Gurdial S.

    2007-04-01

    The use of Helmet-Mounted Display/Tracker (HMD/Ts) is becoming widespread for air-to-air, within visual range target acquisition for a tactical fighter pilot. HMD/Ts provide the aircrew with a significant amount of information on the helmet, which reduces the burden of the aircrew from having to continually look down in the cockpit to receive information. HMD/Ts allow the aircrew to receive flight and targeting information regardless of line-of-sight, which should increase the aircrew's situation awareness and mission effectiveness. Current technology requires that a pilot wearing a Helmet Mounted Display/Tracker be connected to the aircraft with a cable. The design of this cable is complex, costly, and its use can decrease system reliability. Most of the problems associated with the use of cable can be alleviated by using wireless transmission for all signals. This will significantly reduce or eliminate the requirements of the interconnect cable/connector reducing system complexity, and cost, and enhancing system safety. A number of wireless communication technologies have been discussed in this paper and the rationale for selecting one particular technology for this application has been shown. The problems with this implementation and the direction of the future effort are outlined.

  17. Wireless communication technology as applied to head mounted display for a tactical fighter pilot

    NASA Astrophysics Data System (ADS)

    Saini, Gurdial S.

    2006-05-01

    The use of Helmet-Mounted Display/Tracker (HMD/Ts) is becoming widespread for air-to-air, within visual range target acquisition for a tactical fighter pilot. HMD/Ts provide the aircrew with a significant amount of information on the helmet, which reduces the burden of the aircrew from having to continually look down in the cockpit to receive information. HMD/Ts allow the aircrew to receive flight and targeting information regardless of line-of-sight, which should increase the aircrew's situation awareness and mission effectiveness. Current technology requires that a pilot wearing a Helmet Mounted Display/Tracker be connected to the aircraft with a cable. The design of this cable is complex, costly, and its use can decrease system reliability. Most of the problems associated with the use of cable can be alleviated by using wireless transmission for all signals. This will significantly reduce or eliminate the requirements of the interconnect cable/connector reducing system complexity, and cost, and enhancing system safety. A number of wireless communication technologies have been discussed in this paper and the rationale for selecting one particular technology for this application has been shown. The problems with this implementation and the direction of the future effort are outlined.

  18. Usability Comparisons of Head-Mounted vs. Stereoscopic Desktop Displays in a Virtual Reality Environment with Pain Patients.

    PubMed

    Tong, Xin; Gromala, Diane; Gupta, Dimple; Squire, Pam

    2016-01-01

    Researchers have shown that immersive Virtual Reality (VR) can serve as an unusually powerful pain control technique. However, research assessing the reported symptoms and negative effects of VR systems indicate that it is important to ascertain if these symptoms arise from the use of particular VR display devices, particularly for users who are deemed "at risk," such as chronic pain patients Moreover, these patients have specific and often complex needs and requirements, and because basic issues such as 'comfort' may trigger anxiety or panic attacks, it is important to examine basic questions of the feasibility of using VR displays. Therefore, this repeated-measured experiment was conducted with two VR displays: the Oculus Rift's head-mounted display (HMD) and Firsthand Technologies' immersive desktop display, DeepStream3D. The characteristics of these immersive desktop displays differ: one is worn, enabling patients to move their heads, while the other is peered into, allowing less head movement. To assess the severity of physical discomforts, 20 chronic pain patients tried both displays while watching a VR pain management demo in clinical settings. Results indicated that participants experienced higher levels of Simulator Sickness using the Oculus Rift HMD. However, results also indicated other preferences of the two VR displays among patients, including physical comfort levels and a sense of immersion. Few studies have been conducted that compare usability of specific VR devices specifically with chronic pain patients using a therapeutic virtual environment in pain clinics. Thus, the results may help clinicians and researchers to choose the most appropriate VR displays for chronic pain patients and guide VR designers to enhance the usability of VR displays for long-term pain management interventions.

  19. Design of an ultralight head-mounted projective display (HMPD) and its applications in augmented collaborative environments

    NASA Astrophysics Data System (ADS)

    Hua, Hong; Gao, Chunyu; Brown, Leonard; Biocca, Frank; Rolland, Jannick P.

    2002-05-01

    Head-mounted displays (HMDs) are widely used for 3D visualization tasks such as surgical planning, scientific visualization, or engineering design. Even though the HMD technologies have undergone great development, tradeoffs in capability and limitation exist. The concept of head-mounted projective displays (HMPDs) is an emerging technology on the boundary of conventional HMDs and projective displays such as the CAVE technology. It has been recently demonstrated to yield 3D visualization capability with potentially a large FOV, lightweight optics, low distortion, as well as correct occlusion of virtual objects by real objects. As such, the HMPD has been proposed as an alternative to stereoscopic displays for 3D visualization applications. In this paper, a brief review the HMPD technology is followed by the presentation of a recent design and implementation of a compact HMPD prototype based on an ultra-light design of projective optics using diffractive optical element (DOE) and plastic components. Finally, we will include applications of the HMPD technology being developed across three universities for augmented visualization tasks and distributed collaboration in augmented environments.

  20. Development of a surgical navigation system based on augmented reality using an optical see-through head-mounted display.

    PubMed

    Chen, Xiaojun; Xu, Lu; Wang, Yiping; Wang, Huixiang; Wang, Fang; Zeng, Xiangsen; Wang, Qiugen; Egger, Jan

    2015-06-01

    The surgical navigation system has experienced tremendous development over the past decades for minimizing the risks and improving the precision of the surgery. Nowadays, Augmented Reality (AR)-based surgical navigation is a promising technology for clinical applications. In the AR system, virtual and actual reality are mixed, offering real-time, high-quality visualization of an extensive variety of information to the users (Moussa et al., 2012) [1]. For example, virtual anatomical structures such as soft tissues, blood vessels and nerves can be integrated with the real-world scenario in real time. In this study, an AR-based surgical navigation system (AR-SNS) is developed using an optical see-through HMD (head-mounted display), aiming at improving the safety and reliability of the surgery. With the use of this system, including the calibration of instruments, registration, and the calibration of HMD, the 3D virtual critical anatomical structures in the head-mounted display are aligned with the actual structures of patient in real-world scenario during the intra-operative motion tracking process. The accuracy verification experiment demonstrated that the mean distance and angular errors were respectively 0.809±0.05mm and 1.038°±0.05°, which was sufficient to meet the clinical requirements.

  1. Helmet-Mounted Liquid-Crystal Display

    NASA Technical Reports Server (NTRS)

    Smith, Steve; Plough, Alan; Clarke, Robert; Mclean, William; Fournier, Joseph; Marmolejo, Jose A.

    1991-01-01

    Helmet-mounted binocular display provides text and images for almost any wearer; does not require fitting for most users. Accommodates users from smallest interpupillary distance to largest. Two liquid-crystal display units mounted in helmet. Images generated seen from any position head can assume inside helmet. Eyes directed to position for best viewing.

  2. The influence of depth of focus on visibility of monocular head-mounted display symbology in simulation and training applications

    NASA Astrophysics Data System (ADS)

    Winterbottom, Marc D.; Patterson, Robert; Pierce, Byron J.; Covas, Christine; Winner, Jennifer

    2005-05-01

    The Joint Helmet Mounted Cueing System (JHMCS),is being considered for integration into the F-15, F-16, and F-18 aircraft. If this integration occurs, similar monocular head-mounted displays (HMDs) will need to be integrated with existing out-the-window simulator systems for training purposes. One such system is the Mobile Modular Display for Advanced Research and Training (M2DART), which is constructed with flat-panel rear-projection screens around a nominal eye-point. Because the panels are flat, the distance from the eye point to the display screen varies depending upon the location on the screen to which the observer is directing fixation. Variation in focal distance may create visibility problems for either the HMD symbology or the out-the-window imagery presented on the simulator rear-projection display screen because observers may not be able to focus both sets of images simultaneously. The extent to which blurring occurs will depend upon the difference between the focal planes of the simulator display and HMD as well as the depth of focus of the observer. In our psychophysical study, we investigated whether significant blurring occurs as a result of such differences in focal distances and established an optimal focal distance for an HMD which would minimize blurring for a range of focal distances representative of the M2DART. Our data suggest that blurring of symbology due to differing focal planes is not a significant issue within the range of distances tested and that the optimal focal distance for an HMD is the optical midpoint between the near and far rear-projection screen distances.

  3. Real-time EO/IR sensor fusion on a portable computer and head-mounted display

    NASA Astrophysics Data System (ADS)

    Yue, Zhanfeng; Topiwala, Pankaj

    2007-04-01

    Multi-sensor platforms are widely used in surveillance video systems for both military and civilian applications. The complimentary nature of different types of sensors (e.g. EO and IR sensors) makes it possible to observe the scene under almost any condition (day/night/fog/smoke). In this paper, we propose an innovative EO/IR sensor registration and fusion algorithm which runs real-time on a portable computing unit with head-mounted display. The EO/IR sensor suite is mounted on a helmet for a dismounted soldier and the fused scene is shown in the goggle display upon the processing on a portable computing unit. The linear homography transformation between images from the two sensors is precomputed for the mid-to-far scene, which reduces the computational cost for the online calibration of the sensors. The system is implemented in a highly optimized C++ code, with MMX/SSE, and performing a real-time registration. The experimental results on real captured video show the system works very well both in speed and in performance.

  4. 3D optical see-through head-mounted display based augmented reality system and its application

    NASA Astrophysics Data System (ADS)

    Zhang, Zhenliang; Weng, Dongdong; Liu, Yue; Xiang, Li

    2015-07-01

    The combination of health and entertainment becomes possible due to the development of wearable augmented reality equipment and corresponding application software. In this paper, we implemented a fast calibration extended from SPAAM for an optical see-through head-mounted display (OSTHMD) which was made in our lab. During the calibration, the tracking and recognition techniques upon natural targets were used, and the spatial corresponding points had been set in dispersed and well-distributed positions. We evaluated the precision of this calibration, in which the view angle ranged from 0 degree to 70 degrees. Relying on the results above, we calculated the position of human eyes relative to the world coordinate system and rendered 3D objects in real time with arbitrary complexity on OSTHMD, which accurately matched the real world. Finally, we gave the degree of satisfaction about our device in the combination of entertainment and prevention of cervical vertebra diseases through user feedbacks.

  5. Effects of Videogame Distraction using a Virtual Reality Type Head-Mounted Display Helmet on Cold Pressor Pain in Children

    PubMed Central

    Weiss, Karen E.; Dillinger Clendaniel, Lindsay; Law, Emily F.; Ackerman, Claire Sonntag; McKenna, Kristine D.

    2009-01-01

    Objective To test whether a head-mounted display helmet enhances the effectiveness of videogame distraction for children experiencing cold pressor pain. Method Forty-one children, aged 6–14 years, underwent one or two baseline cold pressor trials followed by two distraction trials in which they played the same videogame with and without the helmet in counterbalanced order. Pain threshold (elapsed time until the child reported pain) and pain tolerance (total time the child kept the hand submerged in the cold water) were measured for each cold pressor trial. Results Both distraction conditions resulted in improved pain tolerance relative to baseline. Older children appeared to experience additional benefits from using the helmet, whereas younger children benefited equally from both conditions. The findings suggest that virtual reality technology can enhance the effects of distraction for some children. Research is needed to identify the characteristics of children for whom this technology is best suited. PMID:18367495

  6. The accuracy of the Oculus Rift virtual reality head-mounted display during cervical spine mobility measurement.

    PubMed

    Xu, Xu; Chen, Karen B; Lin, Jia-Hua; Radwin, Robert G

    2015-02-26

    An inertial sensor-embedded virtual reality (VR) head-mounted display, the Oculus Rift (the Rift), monitors head movement so the content displayed can be updated accordingly. While the Rift may have potential use in cervical spine biomechanics studies, its accuracy in terms of cervical spine mobility measurement has not yet been validated. In the current study, a VR environment was designed to guide participants to perform prescribed neck movements. The cervical spine kinematics was measured by both the Rift and a reference motion tracking system. Comparison of the kinematics data between the Rift and the tracking system indicated that the Rift can provide good estimates on full range of motion (from one side to the other side) during the performed task. Because of inertial sensor drifting, the unilateral range of motion (from one side to neutral posture) derived from the Rift is more erroneous. The root-mean-square errors over a 1-min task were within 10° for each rotation axis. The error analysis further indicated that the inertial sensor drifted approximately 6° at the beginning of a trial during the initialization. This needs to be addressed when using the Rift in order to more accurately measure cervical spine kinematics. It is suggested that the front cover of the Rift should be aligned against a vertical plane during its initialization.

  7. Optical See-Through Head Mounted Display Direct Linear Transformation Calibration Robustness in the Presence of User Alignment Noise

    NASA Technical Reports Server (NTRS)

    Axholt, Magnus; Skoglund, Martin; Peterson, Stephen D.; Cooper, Matthew D.; Schoen, Thomas B.; Gustafsson, Fredrik; Ynnerman, Anders; Ellis, Stephen R.

    2010-01-01

    Augmented Reality (AR) is a technique by which computer generated signals synthesize impressions that are made to coexist with the surrounding real world as perceived by the user. Human smell, taste, touch and hearing can all be augmented, but most commonly AR refers to the human vision being overlaid with information otherwise not readily available to the user. A correct calibration is important on an application level, ensuring that e.g. data labels are presented at correct locations, but also on a system level to enable display techniques such as stereoscopy to function properly [SOURCE]. Thus, vital to AR, calibration methodology is an important research area. While great achievements already have been made, there are some properties in current calibration methods for augmenting vision which do not translate from its traditional use in automated cameras calibration to its use with a human operator. This paper uses a Monte Carlo simulation of a standard direct linear transformation camera calibration to investigate how user introduced head orientation noise affects the parameter estimation during a calibration procedure of an optical see-through head mounted display.

  8. Geometrical waveguide in see-through head-mounted display: a review

    NASA Astrophysics Data System (ADS)

    Hou, Qichao; Wang, Qiwei; Cheng, Dewen; Wang, Yongtian

    2016-10-01

    Geometrical waveguide has obvious advantage over other see-through technologies to achieve high resolution, ultra-thin thickness, light weight and full-color display. The general principle of waveguide display is introduced and the key challenges involved with geometrical waveguide display and the way to conquer them is discussed. Ultra-thin geometrical waveguide for see-through HMDs with different properties is reviewed in this paper, including waveguide with partially-reflective mirrors array (PRMA), trapezoidal microstructures and triangular microstructures. Finally, a type of ultra-thin waveguide display which can be fabricated with the technology of injection molding is presented, and the thickness can be reduced to less than 2mm with an EPD of 12mm and a FOV of 36°.

  9. Inclination of standing posture due to the presentation of tilted view through an immersive head-mounted display

    PubMed Central

    Ohmura, Yuji; Yano, Shiro; Katsuhira, Junji; Migita, Masato; Yozu, Arito; Kondo, Toshiyuki

    2017-01-01

    [Purpose] The purpose of the present study is to clarify whether tilted scenery presented through an immersive head-mounted display (HMD) causes the inclination of standing posture. [Subjects and Methods] Eleven healthy young adult males who provided informed consent participated in the experiment. An immersive HMD and a stereo camera were employed to develop a visual inclination system. The subjects maintained a standing posture twice for 5s each while wearing the visual inclination system. They performed this task under two conditions: normal view and 20° leftward tilted view. A three-dimensional motion analysis system was used to measure the subjects’ postures, and two force plates were used to measure the vertical component of the floor reaction force of each leg. [Results] In the 20° leftward tilted view, the head and trunk angles in the frontal plane were similarly inclined toward the left, and the vertical component of the floor reaction force increased in the left leg, whereas it decreased in the right leg. [Conclusion] When the view in the immersive HMD was tilted, the participants’ trunk side bent toward the same side as that of the view. This visual inclination system seems to be a simple intervention for changing standing posture. PMID:28265145

  10. Development of Support Technology for Color AMEL and AMLCD Head-Mounted Displays

    DTIC Science & Technology

    1998-11-01

    the program. Other key participants included: Mr. Roger Stewart - Sarnoff Project Mgmt. Mr. Gerry Becker - Allied Signal Staff Mr. Gary Dohlny...lower power lamp into displays delivered to Amstrong Laboratories for DARPA. In the preceding DARPA subtractive color HMD contract, Honeywell used a...Ipri Gary Dolny David Fürst James Atherton David Sarnoff Research Center CN5300 Princeton, NJ 08543 8/5/96 26 Table of Contents page I

  11. Visual Stability of Objects and Environments Viewed through Head-Mounted Displays

    NASA Technical Reports Server (NTRS)

    Ellis, Stephen R.; Adelstein, Bernard D.

    2015-01-01

    Virtual Environments (aka Virtual Reality) is again catching the public imagination and a number of startups (e.g. Oculus) and even not-so-startup companies (e.g. Microsoft) are trying to develop display systems to capitalize on this renewed interest. All acknowledge that this time they will get it right by providing the required dynamic fidelity, visual quality, and interesting content for the concept of VR to take off and change the world in ways it failed to do so in past incarnations. Some of the surprisingly long historical background of the technology that the form of direct simulation that underlies virtual environment and augmented reality displays will be briefly reviewed. An example of a mid 1990's augmented reality display system with good dynamic performance from our lab will be used to illustrate some of the underlying phenomena and technology concerning visual stability of virtual environments and objects during movement. In conclusion some idealized performance characteristics for a reference system will be proposed. Interestingly, many systems more or less on the market now may actually meet many of these proposed technical requirements. This observation leads to the conclusion that the current success of the IT firms trying to commercialize the technology will depend on the hidden costs of using the systems as well as the development of interesting and compelling content.

  12. Subjective Evaluation of a Semi-Automatic Optical See-Through Head-Mounted Display Calibration Technique.

    PubMed

    Moser, Kenneth; Itoh, Yuta; Oshima, Kohei; Swan, J Edward; Klinker, Gudrun; Sandor, Christian

    2015-04-01

    With the growing availability of optical see-through (OST) head-mounted displays (HMDs) there is a present need for robust, uncomplicated, and automatic calibration methods suited for non-expert users. This work presents the results of a user study which both objectively and subjectively examines registration accuracy produced by three OST HMD calibration methods: (1) SPAAM, (2) Degraded SPAAM, and (3) Recycled INDICA, a recently developed semi-automatic calibration method. Accuracy metrics used for evaluation include subject provided quality values and error between perceived and absolute registration coordinates. Our results show all three calibration methods produce very accurate registration in the horizontal direction but caused subjects to perceive the distance of virtual objects to be closer than intended. Surprisingly, the semi-automatic calibration method produced more accurate registration vertically and in perceived object distance overall. User assessed quality values were also the highest for Recycled INDICA, particularly when objects were shown at distance. The results of this study confirm that Recycled INDICA is capable of producing equal or superior on-screen registration compared to common OST HMD calibration methods. We also identify a potential hazard in using reprojection error as a quantitative analysis technique to predict registration accuracy. We conclude with discussing the further need for examining INDICA calibration in binocular HMD systems, and the present possibility for creation of a closed-loop continuous calibration method for OST Augmented Reality.

  13. New three-dimensional head-mounted display system, TMDU-S-3D system, for minimally invasive surgery application: procedures for gasless single-port radical nephrectomy.

    PubMed

    Kihara, Kazunori; Fujii, Yasuhisa; Masuda, Hitoshi; Saito, Kazutaka; Koga, Fumitaka; Matsuoka, Yoh; Numao, Noboru; Kojima, Kazuyuki

    2012-09-01

    We present an application of a new three-dimensional head-mounted display system that combines a high-definition three-dimensional organic electroluminescent head-mounted display with a high-definition three-dimensional endoscope to minimally invasive surgery, using gasless single-port radical nephrectomy procedures as a model. This system presents the surgeon with a higher quality of magnified three-dimensional imagery in front of the eyes regardless of head position, and simultaneously allows direct vision by moving the angle of sight downward. It is also significantly less expensive than the current robotic surgery system. While carrying out gasless single-port radical nephrectomy, the system provided the surgeon with excellent three-dimensional imagery of the operative field, direct vision of the outside and inside of the patient, and depth perception and tactile feedback through the devices. All four nephrectomies were safely completed within the operative time, blood loss was within usual limits and there were no complications. The display was light enough to comfortably be worn for a long operative time. Our experiences show that the three-dimensional head-mounted display system might facilitate maneuverability and safety in minimally invasive procedures, without prohibitive cost, and thus might mitigate the drawbacks of other three-dimensional vision systems. Because of the potential benefits that this system offers, it deserves further refinements of its role in various minimally invasive surgeries.

  14. The head-mounted microscope.

    PubMed

    Chen, Ting; Dailey, Seth H; Naze, Sawyer A; Jiang, Jack J

    2012-04-01

    Microsurgical equipment has greatly advanced since the inception of the microscope into the operating room. These advancements have allowed for superior surgical precision and better post-operative results. This study focuses on the use of the Leica HM500 head-mounted microscope for the operating phonosurgeon. The head-mounted microscope has an optical zoom from 2× to 9× and provides a working distance from 300 mm to 700 mm. The headpiece, with its articulated eyepieces, adjusts easily to head shape and circumference, and offers a focus function, which is either automatic or manually controlled. We performed five microlaryngoscopic operations utilizing the head-mounted microscope with successful results. By creating a more ergonomically favorable operating posture, a surgeon may be able to obtain greater precision and success in phonomicrosurgery. Phonomicrosurgery requires the precise manipulation of long-handled cantilevered instruments through the narrow bore of a laryngoscope. The head-mounted microscope shortens the working distance compared with a stand microscope, thereby increasing arm stability, which may improve surgical precision. Also, the head-mounted design permits flexibility in head position, enabling operator comfort, and delaying musculoskeletal fatigue. A head-mounted microscope decreases the working distance and provides better ergonomics in laryngoscopic microsurgery. These advances provide the potential to promote precision in phonomicrosurgery.

  15. Assessment of visual space recognition of patients with unilateral spatial neglect and visual field defects using a head mounted display system.

    PubMed

    Sugihara, Shunichi; Tanaka, Toshiaki; Miyasaka, Tomoya; Izumi, Takashi; Shimizu, Koichi

    2016-01-01

    [Purpose] The purpose of this study was the development of a method for presenting diverse visual information and assessing visual space recognition using a new head mounted display (HMD) system. [Subjects] Eight patients: four with unilateral spatial neglect (USN) and four with visual field defects (VFD). [Methods] A test sheet was placed on a desk, and its image was projected on the display of the HMD. Then, space recognition assessment was conducted using a cancellation test and motion analysis of the eyeballs and head under four conditions with images reduced in size and shifted. [Results] Leftward visual search was dominant in VFD patients, while rightward visual search was dominant in USN patients. The angular velocity of leftward eye movement during visual search of the right sheet decreased in both patient types. Motion analysis revealed a tendency of VFD patients to rotate the head in the affected direction under the left reduction condition, whereas USN patients rotated it in the opposite direction of the neglect. [Conclusion] A new HMD system was developed for presenting diverse visual information and assessing visual space recognition which identified the differences in the disturbance of visual space recognition of VFD and USN patients were indicated.

  16. Assessment of visual space recognition in patients with visual field defects using head mounted display (HMD) system: case study with severe visual field defect.

    PubMed

    Sugihara, Shunichi; Tanaka, Toshiaki; Miyasaka, Tomoya; Izumi, Takashi; Shimizu, Koichi

    2013-01-01

    For the quantitative assessment of visual field defects of cerebrovascular patients, we developed a new measurement system that could present various kinds of visual information to the patient. In this system, we use a head mounted display as the display device. The quantitative assessment becomes possible by adding the capability to measure the eye movement and the head movement simultaneously by means of a video apparatus of motion analysis. In our study, we examined the effectiveness of this system by applying it to a patient with serious visual field defects. The visual image of the reduced test paper was presented to the patient, the effect on his/her spatial recognition and eye movement was investigated. The results indicated the increase in the ration of visual search in the reduced side. With the reduced image, the decrease of the angular velocity of eye movement was recognized in the visual search in the defected side. In the motion analysis, the head movement was not observed while the eye movements appeared corresponding to each different conditions. This fact led us to confirm that the patient coped with this kind of test by the eye movement. In this analysis, the effectiveness and the usefulness of the developed system were confirmed that enables us to evaluate the abnormal and compensation movement of the eyes.

  17. Effects of Configuration of Optical Combiner on Near-Field Depth Perception in Optical See-Through Head-Mounted Displays.

    PubMed

    Lee, Sangyoon; Hua, Hong

    2016-04-01

    The ray-shift phenomenon means the apparent distance shift in the display image plane between virtual and physical objects. It is caused by the difference in the refraction of virtual display and see-through optical paths derived from optical combiners that are necessary to provide a see-through capability in optical see-through head-mounted displays. In this work, through a human-subject experiment, we investigated the effects of ray-shift phenomenon induced by the optical combiner on depth perception for near-field distances (40 cm-100 cm). In our experiment, we considered three different configurations of optical combiner: horizontal-tilt and vertical-tilt configurations (using plate beamsplitters horizontally and vertically tilted by 45°, respectively), and non-tilt configuration (using rectangular solid waveguides). Participants' depth perception errors in these configurations were compared with those in an ordinary condition (i.e., the condition where physical objects are directly shown without the displays) and theoretically estimated ones. According to the experimental results, the measured percentage depth perception errors were similar to the theoretically estimated ones, where the amount of estimated percentage depth errors was greater than 0.3%. Furthermore, the participants showed significantly larger depth perception errors in the horizontal-tilt configuration than in an ordinary condition, while no large errors were found in the vertical-tilt configuration. In the non-tilt configuration, the results were dependent on the thickness of optical combiner and target distance.

  18. Helmet-Mounted Display Design Guide

    NASA Technical Reports Server (NTRS)

    Newman, Richard L.; Greeley, Kevin W.

    1997-01-01

    Helmet Mounted Displays (HMDs) present flight, navigation, and weapon information in the pilot's line of sight. The HMD was developed to allow the pilot to retain aircraft and weapon information while looking off boresight. This document reviews current state of the art in HMDs and presents a design guide for the HMD engineer in identifying several critical HMD issues: symbol stabilization, inadequate definitions, undefined symbol drive laws, helmet considerations, and Field Of View (FOV) vs. resolution tradeoff requirements. In particular, display latency is a key issue for HMDs. In addition to requiring further experimental studies, it impacts the definition and control law issues. Symbol stabilization is also critical. In the case of the Apache helicopter, the lack of compensation for pilot head motion creates excessive workload during hovering and Nap Of the Earth (NOE) flight. This translates into excessive training requirements. There is no agreed upon set of definitions or descriptions for how HMD symbols are driven to compensate for pilot head motion. A set of definitions is proposed to address this. There are several specific areas where simulation and flight experiments are needed: development of hover and NOE symbologies which compensate for pilot head movement; display latency and sampling, and the tradeoff between FOV, sensor resolution and symbology.

  19. A three-dimensional head-mounted display system (RoboSurgeon system) for gasless laparoendoscopic single-port partial cystectomy.

    PubMed

    Fujii, Yasuhisa; Kihara, Kazunori; Yoshida, Soichiro; Ishioka, Junichiro; Matsuoka, Yoh; Numao, Noboru; Saito, Kazutaka

    2014-12-01

    We developed a new three-dimensional (3D) head-mounted display (HMD) system (RoboSurgeon system) that combines a high-definition 3D organic electroluminescent HMD with a high-definition 3D endoscope and applies it to minimally invasive surgery. This system presents the surgeon with a higher quality of magnified 3D imagery in front of the eyes, regardless of head position. We report 5 cases of RoboSurgeon gasless laparoendoscopic single-port partial cystectomy, which is carried out as part of our selective bladder-sparing protocol, with a technique utilizing both an intravesical and extravesical approach. While carrying out the surgery, the system provides the surgeon with both excellent 3D imagery of the operative field and clear imagery of the cystoscopy. All procedures were safely completed and there were no complications except for a case of postoperative lymphorrhea. Our experience shows that the 3D HMD system might facilitate maneuverability and safety in various minimally invasive procedures.

  20. Raster graphic helmet-mounted display study

    NASA Technical Reports Server (NTRS)

    Beamon, William S.; Moran, Susanna I.

    1990-01-01

    A design of a helmet mounted display system is presented, including a design specification and development plan for the selected design approach. The requirements for the helmet mounted display system and a survey of applicable technologies are presented. Three helmet display concepts are then described which utilize lasers, liquid crystal display's (LCD's), and subminiature cathode ray tubes (CRT's), respectively. The laser approach is further developed in a design specification and a development plan.

  1. Metamorphism in potential function while maintaining upright posture during exposure to a three-dimensional movie on an head-mounted display.

    PubMed

    Takada, Hiroki; Fujikake, Kazuhiro; Miyao, Masaru

    2009-01-01

    We propose a new index, sparse density (SPD), of stationary stabilograms for detecting the metamorphism in the (temporally averaged) potential function of stochastic differential equations, which occurs when a human attempts to maintain an upright posture. It is known that a mathematical model of the body sway can be developed by a stochastic process. The authors have succeeded in finding the nonlinearity in the potential function. In this study, subjects in a standing position were stimulated by three-dimensional (3-D) movies on an head-mounted display (HMD). We also measured the degree of determinism in the dynamics of the sway of the center of gravity of the subjects. The Double-Wayland algorithm was used as a novel method. As a result, the dynamics of the body sway in the presence of the stimulus as well as in its absence were considered to be stochastic. The metamorphism in the potential function during exposure to the conventional 3-D images could be detected by using the SPD.

  2. Helmet-Mounted Display Design Guide

    DTIC Science & Technology

    2007-11-02

    Accuracy B Head Tilt Accuracy C Head-Tracker Field-of-Regard D Head-Tracker Latency E Fit F Head-borne Weight G Head-Protection H Egress I. References 14 ...form and fit criteria; chapter 14 for functional criteria; and chapter 15 for display criteria. Chapter 16 presents some recommendations for primary...conventional flight control systems. 14 This deviation from the population stereotype must be tested in both normal and ex- treme conditions (including

  3. Mathematical Basis of Knowledge Discovery and Autonomous Intelligent Architectures - Eye-Tracking and Head-Mounted Display/Tracking Computer System for the Remote Control of Robots and Manipulators

    DTIC Science & Technology

    2005-12-14

    High resolution image zone (HRIZ) on computer monitors , displays for collective use and helmet-mounted ones; C). Zone of higher interest displaying...monitor; 2). 3D control of the high-resolution zone in displayed image (HRIZ), for helmet-mounted displays, computer monitors and any displays for...for helmet-mounted displays, computer monitors and any displays for collective use; 3). 3D control of image zone of perception concern (with added

  4. Timing considerations of Helmet Mounted Display performance

    NASA Technical Reports Server (NTRS)

    Tharp, Gregory; Liu, Andrew; French, Lloyd; Lai, Steve; Stark, Lawrence

    1992-01-01

    The Helmet Mounted Display (HMD) system developed in our lab should be a useful teleoperator systems display if it increases operator performance of the desired task; it can, however, introduce degradation in performance due to display update rate constraints and communication delays. Display update rates are slowed by communication bandwidth and/or computational power limitations. We used simulated 3D tracking and pick-and-place tasks to characterize performance levels for a range of update rates. Initial experiments with 3D tracking indicate that performance levels plateau at an update rate between 10 and 20 Hz. We have found that using the HMD with delay decreases performance as delay increases.

  5. Helmet mounted display systems for helicopter simulation

    NASA Technical Reports Server (NTRS)

    Haworth, Loran A.; Bucher, Nancy; Runnings, David

    1989-01-01

    Simulation scientists continually pursue improved flight simulation technology with the goal of closely replicating the 'real world' physical environment. The presentation/display of visual information for flight simulation is one such area enjoying recent technical improvements that are fundamental for conducting simulated operations close to the terrain. Detailed and appropriate visual information is especially critical for Nap-Of-the-Earth (NOE) helicopter flight simulation where the pilot maintains an 'eyes-out' orientation to avoid obstructions and terrain. This paper elaborates on the visually coupled Wide Field Of View Helmet Mounted Display (WFOVHMD) system technology as a viable visual display system for helicopter simulation. In addition the paper discusses research conducted on the NASA-Ames Vertical Motion Simulator that examined one critical research issue for helmet mounted displays.

  6. Eurofighter helmet-mounted display: status update

    NASA Astrophysics Data System (ADS)

    Carter, Stephen J.; Cameron, Alexander A.

    2000-06-01

    BAE SYSTEMS are developing a high performance Helmet Mounted Display system for the Eurofighter/Typhoon combat aircraft. This paper presents an overview of the design solutions, as well as details of the development program status. Finally, it gives some indicators as to future growth applications.

  7. F-16 helmet-mounted display flight evaluations

    NASA Astrophysics Data System (ADS)

    Butterfield, Bruce L.

    1990-10-01

    The Helmet Mounted Display (HMD) concept has long been regarded as a significant advantage to the modern combat pilot. This concept, however, has been limited to simulators, helicopters, and simplistic display types on fighter aircraft. For the first time, wide field of view HMD5, coupled with a head-steered FLIR, have undergone significant flight tests aboard a state of the art fighter aircraft. This paper discusses some of the lessons learned concerning the use of HMDs in a high performance fighter aircraft.

  8. A history of helmet mounted displays

    NASA Astrophysics Data System (ADS)

    Foote, Bob; Melzer, James

    2015-05-01

    In more than 40 years of development, the Helmet-Mounted Display (HMD) has become a key part of the equipment for fixed and rotary wing pilots and ground soldiers, proving to be a force multiplier and reducing user workload. Rockwell Collins has been a key player in the development of modern HMD technology and is currently fielding major HMDs supporting pilots around the world including the Joint Hemet Mounted Cueing System (JHMCS) and Strike Eye. This paper will outline the history of HMDs over the last 40 years for fixed wing, rotorcraft and soldiers and discuss Rockwell Collins' role. We will discuss the development and testing required for introduction of HMDs into the modern pilot environment. Within the paper we will point out some of the misconceptions, facts and legends of HMDS.

  9. Comparison of a Visual and Head Tactile Display for Soldier Navigation

    DTIC Science & Technology

    2013-12-01

    Abbreviations, and Acronyms ACH Advanced Combat Helmet ARL U.S. Army Research Laboratory COTS commercial-off-the-shelf HMTD head - mounted tactile display ...purpose of the study was to determine the advantages of a head - mounted tactile display (HMTD), compared with a map for Soldier navigation in an urban...their overall workload. 15. SUBJECT TERMS tactile modality, head - mounted tactile display , urban environment, threat detection, overall workload

  10. Evaluation of Helmet Mounted Display Alerting Symbology

    NASA Technical Reports Server (NTRS)

    DeMaio, Joe; Rutkowski, Michael (Technical Monitor)

    2000-01-01

    Proposed helicopter helmet mounted displays will be used to alert the pilot to a variety of conditions, from threats to equipment problems. The present research was performed under the NASA Safe All-weather Flight Operations Research (SAFOR) program supported by a joint Army/NASA research agreement. The purpose of the research was to examine ways to optimize the alerting effectiveness of helmet display symbology. The research used two approaches to increasing the effectiveness of alerts. One was to increase the ability of the alert to attract attention by using the entire display surface. The other was to include information about the required response in the alert itself. The investigation was conducted using the NASA Ames Research Center's six-degree-of-freedom vertical motion simulator (VMS) with a rotorcraft cockpit. Helmet display symbology was based on the AH-64's pilot night vision system (PNVS), cruise mode symbology. A standardized mission was developed, that consisted of 11 legs. The mission included four tasks, which allowed variation in the frequency of alerts. The general trend in the data points to a small benefit from both the full-screen alert and the partial information alert.

  11. High Speed Rotor Head Mounted Instrumentation System

    NASA Technical Reports Server (NTRS)

    Hee, Leonard; Reynolds, R. S. (Technical Monitor)

    1997-01-01

    NASA Ames Research Center has been investigating the air flow of a rotor blade on a UH-60 Blackhawk helicopter in-flight. This paper will address the hardware problems and solutions used to design and fabricate an instrumentation system on top of a UH-60 main rotor head. The instrumentation system consisted of 10 data systems operating in parallel and collected data from 370 sensors that are mounted in four rotor blades and on the rotating rotor head. The data was recorded on board the aircraft and simultaneously down linked to the ground station at 7.5 MHz.

  12. TRISTAR III: helmet-mounted display symbology

    NASA Astrophysics Data System (ADS)

    Haworth, Loran A.; Sharkey, Thomas J.; Lee, Alan G.

    1995-05-01

    The US Army Aviation RDEC's Aeroflightdynamics Directorate (AFDD) in cooperation with the Department of Defense Flight Symbology Working Group, the United Kingdom's Defense Research Agency (DRA), and The Technology Cooperative Program Helicopter Technical Panel 6 (HTP6), conducted a Helmet Mounted Display (HMD) symbology investigation using AFDD's Crew Station Research and Development Facility helicopter simulator located at the Ames Research Center, Moffett Field, California. The objectives of the experiment were to examine HMD symbology stabilization, pitch ladders, flight path presentations, and tasks and measures that capture objective and subjective performance differences. Symbology presentation techniques closely modeled specific presentations found in the US Army's AH- 64D Apache helicopter and proposed symbology techniques for the RAH-Comanche and Longbow Apache rotorcraft. Eight helicopter pilots from DOD and DRA participated in the study flying simulated low-altitude rotorcraft maneuvers. This paper describes the simulation flight tests, test results, implications of test findings and recommendations for future HMD investigations.

  13. Integrated helmet mounted display concepts for air combat

    NASA Technical Reports Server (NTRS)

    Clark, Joseph W.

    1995-01-01

    A piloted simulation study was conducted in a dome simulator to evaluate several Helmet Mounted Display (HMD) formats developed as part of the NASA High Alpha Technology Program (HATP). The display formats conveyed energy management, spatial orientation, and weapons management information. The HMD format was compared to a generic Heads Up Display (HUD) typical of current operational fighter aircraft. Pilots were tasked to spend as much time in a weapon solution as possible, to have the correct weapon selected for the envelope they were in, and to avoid the adversary's weapon envelope as much as possible. Several different displays were tested individually and simultaneously to see how separate display concepts coexisted. Objective results showed that the ability for the pilot to select the correct weapon for the envelope he was in increased by 50% in a moderate workload condition and 90% in a high workload condition with the HMD format. In the post-test comments pilots generally favored the helmet display formats over the HUD formats with a few instances where pilots preferred a simple numeric readout of the parameter. Short term exposure effects of the HMD on visual acuity were also measured and showed no advers results.

  14. Distance Perception of Stereoscopically Presented Virtual Objects Optically Superimposed on Physical Objects by a Head-Mounted See-Through Display

    NASA Technical Reports Server (NTRS)

    Ellis, Stephen R.; Bucher, Urs J.; Statler, Irving C. (Technical Monitor)

    1994-01-01

    The influence of physically presented background stimuli on the perceived depth of optically overlaid, stereoscopic virtual images has been studied using headmounted stereoscopic, virtual image displays. These displays allow presentation of physically unrealizable stimulus combinations. Positioning of an opaque physical object either at the initial perceived depth of the virtual image or at a position substantially in front of the virtual image, causes the virtual image to perceptually move closer to the observer. In the case of objects positioned substantially in front of the virtual image, subjects often perceive the opaque object to become transparent. Evidence is presented that the apparent change of position caused by interposition of the physical object is not due to occlusion cues. According, it may have an alternative cause such as variation in the binocular vengeance position of the eyes caused by introduction of the physical object. This effect may complicate design of overlaid virtual image displays for near objects and appears to be related to the relative conspicuousness of the overlaid virtual image and the background. Consequently, it may be related to earlier analyses of John Foley which modeled open-loop pointing errors to stereoscopically presented points of light in terms of errors in determination of a reference point for interpretation of observed retinal disparities. Implications for the design of see-through displays for manufacturing will be discussed.

  15. Comanche Helmet-Mounted Display Symbology Simulation

    NASA Technical Reports Server (NTRS)

    Turpin, Terry S.; Dowell, Susan R.; Szoboszlay, Zoltan

    2006-01-01

    The Aeroflightdynamics Directorate (AMRDEC) conducted a simulation to examine the performance of the Comanche Contact Analog world-referenced symbology displayed on the Comanche HIDSS when compared with a compressed symbology design similar to that specified by the former MIL-STD 1295. Six experimental test pilots flew one modified ADS-33 maneuver (hover turn, bob-up), an unusual attitude recovery, and two terrain flight tactical tasks in the NASA Vertical Motion Simulator (VMS). Analysis of the pilot objective performance data and subjective data showed the following results. Objective test results showed that 1295 symbology yielded more rapid maneuvering in the hover turn bob-up than Contact Analog symbology. The average margin of difference in the time to complete the maneuver was approximately two seconds, which was statistically significant. There were no significant differences measured between symbology sets with respect to altitude or position performance measures for all other maneuvers. The NOE target ID task data showed improved accuracy in determining heading to target when using Contact Analog over MIL-STD-1295. Subjective test results, including handling qualities ratings (HQRs) and NASA-TLX workload ratings, showed small but consistent advantages of 1295 symbology over Contact Analog for most parameters. For the bob-up maneuver, 1295 symbology handling qualities were rated Desired for lateral position error and time to complete whereas Contact Analog was rated adequate. The average HQRs for all other maneuvers were rated the same for both symbology sets. Pilot comments and the results of an online questionnaire more strongly favored 1295 over Contact Analog. Repeated comments from all six pilots led to a focus on design issues with six Contact Analog symbols. Those symbols were the heading tape, horizon line, radar altitude six-second predictor, the position of the torque symbol, the absence of a hover position cue, and the widespread positioning of

  16. Head-mounted spatial instruments: Synthetic reality or impossible dream

    NASA Technical Reports Server (NTRS)

    Ellis, Stephen R.; Grunwald, Arthur; Velger, Mordekhai

    1988-01-01

    A spatial instrument is defined as a display device which has been either geometrically or symbolically enhanced to better enable a user to accomplish a particular task. Research conducted over the past several years on 3-D spatial instruments has shown that perspective displays, even when viewed from the correct viewpoint, are subject to systematic viewer biases. These biases interfere with correct spatial judgements of the presented pictorial information. It is also found that deliberate, appropriate geometric distortion of the perspective projection of an image can improve user performance. These two findings raise intriguing questions concerning the design of head-mounted spatial instruments. The design of such instruments may not only require the introduction of compensatory distortions to remove the neutrally occurring biases but also may significantly benefit from the introduction of artificial distortions which enhance performance. These image manipulations, however, can cause a loss of visual-vestibular coordination and induce motion sickness. Additionally, adaptation to these manipulations is apt to be impaired by computational delays in the image display. Consequently, the design of head-mounted spatial instruments will require an understanding of the tolerable limits of visual-vestibular discord.

  17. Presentation of IR pictures on helmet-mounted displays

    NASA Astrophysics Data System (ADS)

    Balzarotti, Giorgio; Fiori, Lorenzo; Malfagia, Roberto

    1994-06-01

    The head tracking systems for helmet mounted displays (HMD) have actually achieved a high degree of accuracy, thus allowing the precise control of the line of sight (LOS) of electrooptical vision sensors. Therefore, the possibility to fly day and night having on the helmet visors the pictures generated by a steerable infrared (IR) sensor slaved to the pilot's head becomes nowadays realistic. The paper describes the results of a technical analysis performed on a system based on a steerable IR sensor integrated with an advanced HMD for navigation aid purpose in a modern fighter. Integration aspects and human engineering factors are also widely analyzed. This paper considers the parameters which lead to an imperfect static or dynamic overlay of the generated IR picture with the external world, as seen by the pilot through the helmet visors, and the effects of such misalignment. The finite angular excursion of the IR sensor LOS, due to the gimbals limits, has been taken into account, and the necessary transitions to and from the LLTVs integrated within the helmet, suitable to cover all possible head motions, have been investigated. An approach for the fusion of information generated by the LLTVs and the IR sensor is also reported. The limits and constraints of navigation using steerable IR sensors are also highlighted with respect to safety aspects.

  18. A helmet mounted display to adapt the telerobotic environment to human vision

    NASA Technical Reports Server (NTRS)

    Tharp, Gregory; Liu, Andrew; Yamashita, Hitomi; Stark, Lawrence

    1990-01-01

    A Helmet Mounted Display system has been developed. It provides the capability to display stereo images with the viewpoint tied to subjects' head orientation. The type of display might be useful in a telerobotic environment provided the correct operating parameters are known. The effects of update frequency were tested using a 3D tracking task. The effects of blur were tested using both tracking and pick-and-place tasks. For both, researchers found that operator performance can be degraded if the correct parameters are not used. Researchers are also using the display to explore the use of head movements as part of gaze as subjects search their visual field for target objects.

  19. Cuff-Mounted Electronic Checklist Display Unit

    NASA Technical Reports Server (NTRS)

    Marmolejo, Jose A.; Fullerton, Richard; Cottingham, Paul; Chen, Chen-Hsiang; Shepherd, Charles

    1995-01-01

    Portable electronic display unit developed to provide text and pictures to guide users through complex technical procedures in field. Touch screen divided into six areas; touching each area causes display of specific menu or page, or activates electronic stopwatch. Unit strapped onto user's wrist in manner of wristwatch, leaving user's hands free to carry out procedures while referring to displayed information. Intended originally for use by astronaut in space suit, unit also eases tasks of technicians on Earth by providing quick and easy access to information, without need to carry and thumb through massive service manuals.

  20. Helmet-mounted displays on the modern battlefield

    NASA Astrophysics Data System (ADS)

    Casey, Curtis J.

    1999-07-01

    The increasing need for information being demanded by the battlefield commander in order to increase and maintain overall situational awareness in execution of the battle plan has caused a proliferation of devices and methods to be evaluated in Army Warfighting Experiments (AWEs). The results are often technology driving requirements without sufficient consideration given to the requirements of the soldier in battle. We are witnessing an overload of information being imposed on both the commander and the individual soldier, employing equipment capable of providing information from numerous sources across multiple, non-compatible platforms. Displays for this information range from large, power-hungry, big screen TVs to small, rugged computers and head-mounted displays (HMDs) for the individual combat soldier. The former requires large power supplies and is not suitable for a mobile army; the latter offers poor resolution and interferes with the duties of a soldier in combat. While we must continue to explore technology to solve some of the problems on the modern battlefield, we, as developers of technology, cannot lose sight of the purpose of the combat soldier: To wage war on a highly complex and mobile battlefield, whether it be in a country or urban environment; to seek out the enemy, engage him, destroy his ability to fight.

  1. Body-worn optical wireless link to helmet mounted display

    NASA Astrophysics Data System (ADS)

    Charlton, David W.; Watson, Malcolm A.; White, Henry J.

    2010-10-01

    This paper describes a prototype demonstration of a high bandwidth data link between the fuselage of an aircraft and a helmet mounted display. A single data receiver, powered by battery and equipped with a light-collecting optical antenna to increase optical gain, is worn on the body of the pilot, with a fast-modulated laser transmitter mounted in the pilot's seat area. The combination covered the expected range of body movement that a pilot typically undergoes during a flight. Uncompressed, {140Mbps video data is streamed over the free-space link to a BAE Systems helmet mounted display (Q-Sight™) worn by the pilot.

  2. Using a Head-Mounted Camera to Infer Attention Direction

    ERIC Educational Resources Information Center

    Schmitow, Clara; Stenberg, Gunilla; Billard, Aude; von Hofsten, Claes

    2013-01-01

    A head-mounted camera was used to measure head direction. The camera was mounted to the forehead of 20 6- and 20 12-month-old infants while they watched an object held at 11 horizontal (-80° to + 80°) and 9 vertical (-48° to + 50°) positions. The results showed that the head always moved less than required to be on target. Below 30° in the…

  3. Assessment of a head-mounted miniature monitor

    NASA Technical Reports Server (NTRS)

    Hale, J. P., II

    1992-01-01

    Two experiments were conducted to assess the capabilities and limitations of the Private Eye, a miniature, head-mounted monitor. The first experiment compared the Private Eye with a cathode ray tube (CRT) and hard copy in both a constrained and unconstrained work envelope. The task was a simulated maintenance and assembly task that required frequent reference to the displayed information. A main effect of presentation media indicated faster placement times using the CRT as compared with hard copy. There were no significant differences between the Private Eye and either the CRT or hard copy for identification, placement, or total task times. The goal of the second experiment was to determine the effects of various local visual parameters on the ability of the user to accurately perceive the information of the Private Eye. The task was an interactive video game. No significant performance differences were found under either bright or dark ambient illumination environments nor with either visually simple or complex task backgrounds. Glare reflected off of the bezel surrounding the monitor did degrade performance. It was concluded that this head-mounted, miniature monitor could serve a useful role for in situ operations, especially in microgravity environments.

  4. Visual field information in Nap-of-the-Earth flight by teleoperated Helmet-Mounted displays

    NASA Technical Reports Server (NTRS)

    Grunwald, Arthur J.; Kohn, S.; Merhav, S. J.

    1991-01-01

    The human ability to derive Control-Oriented Visual Field Information from teleoperated Helmet-Mounted displays in Nap-of-the-Earth flight, is investigated. The visual field with these types of displays originates from a Forward Looking Infrared Radiation Camera, gimbal-mounted at the front of the aircraft and slaved to the pilot's line-of-sight, to obtain wide-angle visual coverage. Although these displays are proved to be effective in Apache and Cobra helicopter night operations, they demand very high pilot proficiency and work load. Experimental work presented in the paper has shown that part of the difficulties encountered in vehicular control by means of these displays can be attributed to the narrow viewing aperture and head/camera slaving system phase lags. Both these shortcomings will impair visuo-vestibular coordination, when voluntary head rotation is present. This might result in errors in estimating the Control-Oriented Visual Field Information vital in vehicular control, such as the vehicle yaw rate or the anticipated flight path, or might even lead to visuo-vestibular conflicts (motion sickness). Since, under these conditions, the pilot will tend to minimize head rotation, the full wide-angle coverage of the Helmet-Mounted Display, provided by the line-of-sight slaving system, is not always fully utilized.

  5. Helmet-Mounted Display Of Clouds Of Harmful Gases

    NASA Technical Reports Server (NTRS)

    Diner, Daniel B.; Barengoltz, Jack B.; Schober, Wayne R.

    1995-01-01

    Proposed helmet-mounted opto-electronic instrument provides real-time stereoscopic views of clouds of otherwise invisible toxic, explosive, and/or corrosive gas. Display semitransparent: images of clouds superimposed on scene ordinarily visible to wearer. Images give indications on sizes and concentrations of gas clouds and their locations in relation to other objects in scene. Instruments serve as safety devices for astronauts, emergency response crews, fire fighters, people cleaning up chemical spills, or anyone working near invisible hazardous gases. Similar instruments used as sensors in automated emergency response systems that activate safety equipment and emergency procedures. Both helmet-mounted and automated-sensor versions used at industrial sites, chemical plants, or anywhere dangerous and invisible or difficult-to-see gases present. In addition to helmet-mounted and automated-sensor versions, there could be hand-held version. In some industrial applications, desirable to mount instruments and use them similarly to parking-lot surveillance cameras.

  6. Helmet-Mounted Display Symbology and Stabilization Concepts

    NASA Technical Reports Server (NTRS)

    Newman, Richard L.

    1995-01-01

    The helmet-mounted display (HMD) presents flight, sensor, and weapon information in the pilot's line of sight. The HMD was developed to allow the pilot to retain aircraft and weapon information and to view sensor images while looking off boresight.

  7. Advances in rotary-wing helmet-mounted displays

    NASA Astrophysics Data System (ADS)

    Hewlett, David; Cameron, Alexander A.

    2000-06-01

    BAE SYSTEMS are developing a high performance Helmet Mounted Display system for the US Marine corps AH-1Z attack helicopter. This paper presents an overview of the design solution, as well as details of the rational behind the design and some of the lesson learnt. Finally, it gives some indicators as to future growth.

  8. Designing the integrated helmet-mounted display for pilots

    NASA Astrophysics Data System (ADS)

    Liu, Yu

    1998-08-01

    The design of an integrated helmet-mounted display for pilots is described. The purpose of the design is to provide sufficient information, fine comfort for wear, and low cost. Some factors are considered and compromised in the design. A 3rd generation image intensifier, a half inch cathode ray tube, two combiner eyepieces, and some optical assembly are used in the display. The optical axes of the objective lens, the intensifier, and the combiners are put on one plane with the line of sight of the water. A intensifying channel, a display channel and a see-through channel are included in the display system. These channel present fight symbology and objective scene by multiform way. Accordingly, the design has a great redundance, and the display has fine reliability and the location of the CG, low cost and weight.

  9. The effect of configural displays on pilot situation awareness in helmet-mounted displays

    NASA Astrophysics Data System (ADS)

    Jenkins, Joseph Christopher

    The current research utilized configural displays within the domain of aviation to assess what design features of configural displays contribute to the formation of operator situation awareness (SA). Configural displays map system information relevant to operator goals onto geometric shapes called emergent features. An emergent feature is formed from the combination of individual line segments to produce a global feature more perceptually salient and recognized sooner than the individual parts themselves. Configural displays have been shown in previous research to provide better operator performance for integration tasks where multiple pieces of information must be considered at once, yet the design aspects of configural displays that impact the formation of operator SA have yet to be determined. The current research compared the design features of three aviation configural displays over four experiments to quantify what aspects of configural displays would impact operator SA. The research sought to determine whether the simple act of representing system information in configural displays using emergent features is sufficient for facilitating operator SA or do other design factors need to be considered? Operator SA was assessed using explicit and implicit measures of SA from operator task performance in addition to a subjective SA rating scale. The recognition of aircraft attitude (climb/dive flight angles) when briefly presented to pilots in Experiment 1 revealed significant performance differences for the Arc Segment Attitude Reference (ASAR) configural display which mapped aircraft attitude information onto a circular shape versus the traditional aircraft head-up display (HUD) ladder found in the Joint Strike Fighter (JSF) HUD and Dual-Articulated (DA) HUD. The current research in Experiment 1 provides evidence that configural displays such as the ASAR that utilize emergent features well mapped to fully relate the information needed for a task will facilitate

  10. [Optoelectronic display system for minimal invasive laparoscopic operations: initial experiences with new face-mounted display video eyeglasses].

    PubMed

    Harms, J; Schneider, A

    2002-03-01

    A major aspect of efforts to improve minimally invasive surgery is the optimization of visualization, which is currently unsatisfactory due to the limited number of pixels in the monitors used, and inadequate alignment of the optical axis. Optical systems provided with commercially available head-mounted displays have failed to improve optical quality and significantly facilitate or improve laparoscopic surgery [2,3]. Innovations in the field of consumer video using a new optical prism and a high-resolution matrix (180,000 pixels) are the core elements of a new face-mounted display (FMD-Eye-Trek 700, Olympus Optical Co, Europe GmbH, Hamburg, Germany) that provides high image quality. This device has now been tested for the first time during laparoscopic procedures (n = 14) and combined laparoscopic-endoscopic procedures (n = 7) under clinical conditions. Impressive optical, ergonomic and surgeon-related benefits were established.

  11. A review of head-worn display research at NASA Langley Research Center

    NASA Astrophysics Data System (ADS)

    Arthur, Jarvis J.; Bailey, Randall E.; Williams, Steven P.; Prinzel, Lawrence J.; Shelton, Kevin J.; Jones, Denise R.; Houston, Vincent

    2015-05-01

    NASA Langley has conducted research in the area of helmet-mounted/head-worn displays over the past 30 years. Initially, NASA Langley's research focused on military applications, but recently has conducted a line of research in the area of head-worn displays for commercial and business aircraft. This work has revolved around numerous simulation experiments as well as flight tests to develop technology and data for industry and regulatory guidance. The paper summarizes the results of NASA's helmet-mounted/head-worn display research. Of note, the work tracks progress in wearable collimated optics, head tracking, latency reduction, and weight. The research lends credence that a small, sunglasses-type form factor of the head-worn display would be acceptable to commercial pilots, and this goal is now becoming technologically feasible. The research further suggests that a head-worn display may serve as an "equivalent" Head-Up Display (HUD) with safety, operational, and cost benefits. "HUD equivalence" appears to be the economic avenue by which head-worn displays can become main-stream on the commercial and business aircraft flight deck. If this happens, NASA's research suggests that additional operational benefits using the unique capabilities of the head-worn display can open up new operational paradigms.

  12. A Review of Head-Worn Display Research at NASA Langley Research Center

    NASA Technical Reports Server (NTRS)

    Arthur, Jarvis (Trey) J., III; Bailey, Randall E.; Williams, Steven P.; Prinzel, Lawrence J., III; Shelton, Kevin J.; Jones, Denise R.; Houston, Vincent

    2015-01-01

    NASA Langley has conducted research in the area of helmet-mounted/head-worn displays over the past 30 years. Initially, NASA Langley's research focused on military applications, but recently it has conducted a line of research in the area of head-worn displays for commercial and business aircraft. This work has revolved around numerous simulation experiments as well as flight tests to develop technology and data for industry and regulatory guidance. The paper summarizes the results of NASA's helmet-mounted/head-worn display research. Of note, the work tracks progress in wearable collimated optics, head tracking, latency reduction, and weight. The research lends credence that a small, sunglasses-type form factor of the head-worn display would be acceptable to commercial pilots, and this goal is now becoming technologically feasible. The research further suggests that a head-worn display may serve as an "equivalent" Head-Up Display (HUD) with safety, operational, and cost benefits. "HUD equivalence" appears to be the economic avenue by which head-worn displays can become main-stream on the commercial and business aircraft flight deck. If this happens, NASA's research suggests that additional operational benefits using the unique capabilities of the head-worn display can open up new operational paradigms.

  13. A universal and smart helmet-mounted display of large FOV

    NASA Astrophysics Data System (ADS)

    Zhang, Nan; Weng, Dongdong; Wang, Yongtian; Li, Xuan; Liu, Youhai

    2011-11-01

    HMD (head-mounted display) is an important virtual reality device, which has played a vital role in VR application system. Compared with traditional HMD which cannot be applied in the daily life owing to their disadvantage on the price and performance, a new universal and smart Helmet-Mounted Display of large FOV uses excellent performance and widespread popularity as its starting point. By adopting simplified visual system and transflective system that combines the transmission-type and reflection-type display system with transflective glass based on the Huggens-Fresnel principle, we have designed a HMD with wide field of view, which can be easy to promote and popularize. Its resolution is 800*600, and field of view is 36.87°(vertical)* 47.92°(horizontal). Its weight is only 1080g. It has caught up with the advanced world levels.

  14. Binocular Rivalry and Head Worn Displays

    DTIC Science & Technology

    2007-12-01

    as entertainment or other personal use ( Hakkinen , 2004; Velger, 1998), Binocular Rivalry and Head-Worn Displays Robert Patterson, Washington State...standard computer monitor when an unmanned aerial vehicle control task was performed (however, see Peli, 1998). Laramee and Ware (2002; see also Hakkinen ...several researchers to be wary of their use or to recommend that they be used only out of the user’s direct line of sight ( Hakkinen , 2004; Laramee

  15. Holographic Combiners for Head-Up Displays

    DTIC Science & Technology

    1977-10-01

    AFAL-TR-77 -110 S HOLOGRAPHIC COMBINERS FOR HEAD-UP DISPLAYS S Radar and Optics Division Environmental Research Institute of Michigan P.O. Box 8618...to 200. SECURITY CLASSIFICATION OF THIS PAGE(RWihen Data Entered) FOREWORD This report was prepared by the Radar and Optics Division of the...with fringes parallel to the surface......31 Figure 13. Raytrace through the F-4 HUD with a holographic combiner

  16. South Fork Latrine, interior showing head with steel tank mounted ...

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

    South Fork Latrine, interior showing head with steel tank mounted to wall; view south - Fort McKinley, South Fork Latrine, West side of East Side Drive, approximately 225 feet south of Weymouth Way, Great Diamond Island, Portland, Cumberland County, ME

  17. Head-Up Displays and Attention Capture

    NASA Technical Reports Server (NTRS)

    Prinzel, Lawrence J., III; Risser, Matthew

    2004-01-01

    The primary role of head-up displays (HUDs) is to provide primary flight, navigation, and guidance information to the pilot in a forward field-of-view on a head-up transparent screen. Therefore, this theoretically allows for optimal control of an aircraft through the simultaneous scanning of both instrument data and the out-the-window scene. However, despite significant aviation safety benefits afforded by HUDs, a number of accidents have shown that their use does not come without costs. The human factors community has identified significant issues related to the pilot distribution of near and far domain attentional resources because of the compellingness of symbology elements on the HUD; a concern termed, attention or cognitive capture. The paper describes the phenomena of attention capture and presents a selected survey of the literature on the etiology and potential prescriptions.

  18. Helmet-mounted display systems for flight simulation

    NASA Technical Reports Server (NTRS)

    Haworth, Loren A.; Bucher, Nancy M.

    1989-01-01

    Simulation scientists are continually improving simulation technology with the goal of more closely replicating the physical environment of the real world. The presentation or display of visual information is one area in which recent technical improvements have been made that are fundamental to conducting simulated operations close to the terrain. Detailed and appropriate visual information is especially critical for nap-of-the-earth helicopter flight simulation where the pilot maintains an 'eyes-out' orientation to avoid obstructions and terrain. This paper describes visually coupled wide field of view helmet-mounted display (WFOVHMD) system technology as a viable visual presentation system for helicopter simulation. Tradeoffs associated with this mode of presentation as well as research and training applications are discussed.

  19. Helmet-Mounted Displays For Helicopter Pilotage: Design Configuration Tradeoffs, Analyses, And Test

    NASA Astrophysics Data System (ADS)

    Lohmann, Robert A.; Weisz, Alexander Z.

    1989-09-01

    Human engineering criteria applicable to the design of helmet mounted displays for use with night vision sensors, such as forward looking infra-red (FLIR) or low light level television (LLTV), are stated and reviewed. Systems requirements are presented which call for pilot operation at night that is as equivalent as practicable to flight under normal daytime visual rules. Requirements are developed that utilize head motion coupled to sensor movement to achieve the semblance of daytime pilotage while conducting operations at night under the cover of deep darkness. At the outset, salient factors are identified and prioritized which are applied to further design tradeoffs leading to helmet mounted visor displays. The prime design objectives being operational suitability, acceptability by the pilot community, reduced crew training requirements and minimal logistics support. In conclusion, alternate design configurations, computer analyses, operating experience, and pilot reaction are cited. Items to be addressed include: overall head supported weight, center-of-gravity, and other ergonomic factors affecting pilot acceptance: such as: comfort, eye-relief, total and instantaneous field of view, full or partial overlap of left-eye and right-eye fields of coverage, and head movement-to-sensor servo response. In addition, items of interest to the operating command: such as: training (ease or difficulty), maintenance of proficiency, and ease of viewing, will be discussed in light of data and operating experience from recently conducted flight trials. Finally, compatibility with nuclear biological and chemical (NBC) defense equipment and requirements, and laser eye protection will be discussed.

  20. Solutions to helmet-mounted display visual correction compatibility issues

    NASA Astrophysics Data System (ADS)

    Rash, Clarence E.; Kalich, Melvyn E.; van de Pol, Corina

    2002-08-01

    To meet the goal of 24-hour, all-weather operation, U.S. Army aviation uses a number of imaging sensor systems on its aircraft. Imagery provided by these systems is presented on helmet-mounted displays (HMDs). Fielded systems include the Integrated Helmet Display Sighting System (IHADSS) used on the AH-64 Apache. Proposed future HMD systems such as the Helmet Integrated Display Sighting System (HIDSS) and the Microvision, Inc., Aircrew Integrated Helmet System (AIHS) scanning laser system are possible choices for the Army's RAH-66 Comanche helicopter. Ever present in current and future HMD systems is the incompatibility problem between the design-limited physical eye relief of the HMD and the need to provide for the integration of laser and nuclear, biological and chemical (NBC) protection, as well as the need to address the changing optical and vision requirements of the aging aviator. This paper defines the compatibility issue, reviews past efforts to solve this problem (e.g., contact lenses, NBC masks, optical inserts, etc.), and identifies emerging techniques (e.g., refractive surgery, adaptive optics, etc.) that require investigation.

  1. Quick-disconnect harness system for helmet-mounted displays

    NASA Astrophysics Data System (ADS)

    Bapu, P. T.; Aulds, M. J.; Fuchs, Steven P.; McCormick, David M.

    1992-10-01

    We have designed a pilot's harness-mounted, high voltage quick-disconnect connectors with 62 pins, to transmit voltages up to 13.5 kV and video signals with 70 MHz bandwidth, for a binocular helmet-mounted display system. It connects and disconnects with power off, and disconnects 'hot' without pilot intervention and without producing external sparks or exposing hot embers to the explosive cockpit environment. We have implemented a procedure in which the high voltage pins disconnect inside a hermetically-sealed unit before the physical separation of the connector. The 'hot' separation triggers a crowbar circuit in the high voltage power supplies for additional protection. Conductor locations and shields are designed to reduce capacitance in the circuit and avoid crosstalk among adjacent circuits. The quick- disconnect connector and wiring harness are human-engineered to ensure pilot safety and mobility. The connector backshell is equipped with two hybrid video amplifiers to improve the clarity of the video signals. Shielded wires and coaxial cables are molded as a multi-layered ribbon for maximum flexibility between the pilot's harness and helmet. Stiff cabling is provided between the quick-disconnect connector and the aircraft console to control behavior during seat ejection. The components of the system have been successfully tested for safety, performance, ergonomic considerations, and reliability.

  2. MEMS scanned laser head-up display

    NASA Astrophysics Data System (ADS)

    Freeman, Mark O.

    2011-03-01

    Head-up displays (HUD) in automobiles and other vehicles have been shown to significantly reduce accident rates by keeping the driver's eyes on the road. The requirements for automotive HUDs are quite demanding especially in terms of brightness, dimming range, supplied power, and size. Scanned laser display technology is particularly well-suited to this application since the lasers can be very efficiently relayed to the driver's eyes. Additionally, the lasers are only turned on where the light is needed in the image. This helps to provide the required brightness while minimizing power and avoiding a background glow that disturbs the see-through experience. Microvision has developed a couple of HUD architectures that are presented herein. One design uses an exit pupil expander and relay optics to produce a high quality virtual image for built-in systems where the image appears to float above the hood of the auto. A second design uses a patented see-through screen technology and pico projector to make automotive HUDs available to anyone with a projector. The presentation will go over the basic designs for the two types of HUD and discuss design tradeoffs.

  3. Holography for automotive head-up displays

    NASA Astrophysics Data System (ADS)

    Ramsbottom, Andrew P.; Sergeant, Shirley A.; Sheel, David W.

    1992-05-01

    There is increasing interest in head-up-displays (HUDs) for automotive use. A number of technologies could be employed for the combiner function including plain glass reflection, dielectric enhancement, and holography. This paper will consider the potential role for conformal holography as the combiner element by initially reviewing the system requirements from an optical design view, how these differ significantly from an avionic HUD, and how they relate to material characteristics and process features. This will involve a consideration in some detail of the effects of specified hologram properties and lamination features on the optical performance and image characteristic of a car HUD. In particular, we shall examine such features as hologram efficiency, bandwidth, tuning position, environmental stability, tolerances, and film lamination effects and how these may influence the key optical characteristics of the image, i.e., distortions, blur, brightness, double imaging (separation and contrast) outside world view, etc.. A theoretical model based on Kogelnik coupled wave theory will be used to illustrate the various tradeoffs between hologram properties and process, image features, and display characteristics (bandwidth, polarization, etc.). This analysis will be related to properties of currently available holographic materials with reference to recent experimental work.

  4. Manufacturing development of visor for binocular helmet mounted display

    NASA Astrophysics Data System (ADS)

    Krevor, David; Edwards, Timothy; Larkin, Eric; Skubon, John; Speirs, Robert; Sowden, Tom

    2007-09-01

    The HMD (Helmet Mounted Display) visor is a sophisticated article. It is both the optical combiner for the display and personal protective equipment for the pilot. The visor must have dimensional and optical tolerances commensurate with precision optics; and mechanical properties sufficient for a ballistic shield. Optimized processes and tooling are necessary in order to manufacture a functional visor. This paper describes the manufacturing development of the visor for the Joint Strike Fighter (JSF) HMD. The analytical and experimental basis for the tool and manufacturing process development are described; as well as the metrological and testing methods to verify the visor design and function. The requirements for the F-35 JSF visor are a generation beyond those for the HMD visor which currently flies on the F-15, F-16 and F/A-18. The need for greater precision is manifest in the requirements for the tooling and molding process for the visor. The visor is injection-molded optical polycarbonate, selected for its combination of optical, mechanical and environmental properties. Proper design and manufacture of the tool - the mold - is essential. Design of the manufacturing tooling is an iterative process between visor design, mold design, mechanical modeling and polymer-flow modeling. Iterative design and manufacture enable the mold designer to define a polymer shrinkage factor more precise than derived from modeling or recommended by the resin supplier.

  5. Perceptual issues for color helmet-mounted displays: luminance and color contrast requirements

    NASA Astrophysics Data System (ADS)

    Harding, Thomas H.; Rash, Clarence E.; Lattimore, Morris R.; Statz, Jonathan; Martin, John S.

    2016-05-01

    Color is one of the latest design characteristics of helmet-mounted displays (HMDs). It's inclusion in design specifications is based on two suppositions: 1) color provides an additional method of encoding information, and 2) color provides a more realistic, and hence more intuitive, presentation of information, especially pilotage imagery. To some degree, these two perceived advantages have been validated with head-down panel-mounted displays, although not without a few problems associated with visual physiology and perception. These problems become more prevalent when the user population expands beyond military aviators to a general user population, of which a significant portion may have color vision deficiencies. When color is implemented in HMDs, which are eyes-out, see-through displays, visual perception issues become an increased concern. A major confound with HMDs is their inherent see-through (transparent) property. The result is color in the displayed image combines with color from the outside (or in-cockpit) world, possibly producing a false perception of either or both images. While human-factors derived guidelines based on trial and error have been developed, color HMD systems still place more emphasis on colorimetric than perceptual standards. This paper identifies the luminance and color contrast requirements for see-through HMDs. Also included is a discussion of ambient scene metrics and the choice of symbology color.

  6. Helmet-mounted display technology on the VISTA NF-16D

    NASA Astrophysics Data System (ADS)

    Underhill, Gregory P.; Bailey, Randall E.; Markman, Steve

    1997-06-01

    Wright Laboratory's Variable-Stability In-Flight Simulator Test Aircraft (VISTA) NF-16D is the newest in-flight simulator in the USAF inventory. A unique research aircraft, it will perform a multitude of missions: to develop and evaluate flight characteristics of new aircraft that have not yet flown, and perform research in the areas of flying qualities, flight control design, pilot-vehicle interface, weapons and avionics integration, and to train new test pilots. The VISTA upgrade will enhance the simulation fidelity and research capabilities by adding a programmable helmet-mounted display (HMD) and head-up display (HUD) in the front cockpit. The programmable HMD consists of a GEC- Marconi Avionics Viper II Helmet-Mounted Optics Module integrated with a modified Helmet Integrated Systems Limited HGU-86/P helmet, the Honeywell Advanced Metal Tolerant tracker, and a GEC-Mounted Tolerant tracker, and a GEC- Marconi Avionics Programmable Display Generator. This system will provide a real-time programmable HUD and monocular stroke capable HMD in the front cockpit. The HMD system is designed for growth to stroke-on-video, binocular capability. This paper examines some of issues associated with current HMD development, and explains the value of rapid prototyping or 'quick-look' flight testing on the VISTA NF-16D. A brief overview of the VISTA NF-16D and the hardware and software modifications made to incorporate the programmable display system is give, as well as a review of several key decisions that were made in the programmable display system implementation. The system's capabilities and what they mean to potential users and designers are presented, particularly for pilot-vehicle interface research.

  7. Attentional limitations with Head-Up Displays

    NASA Technical Reports Server (NTRS)

    Mccann, Robert S.; Foyle, David C.; Johnston, James C.

    1993-01-01

    Recent models of visual information processing suggest that visual attention can be focussed on either Head-Up Displays (HUD) or on the world beyond them, but not on both simultaneously. This hypothesis was tested in a part-task simulation in which subjects viewed a simulated approach to a runway with a HUD superimposed. An alphanumeric cue ('IFR' or 'VFR') appeared on either the HUD or the runway and was followed by two sets of three geometric forms; one set on the HUD and one set on the runway. Each set contained one potential target, either a stop sign or a diamond. If the cue spelled 'IFR', subjects made a speeded response based on the identity of the HUD target; if the cue spelled 'VFR', subjects made a speeded response based on the identity of the runway target. Regardless of cue location (HUD or Runway), responses were faster when the cue and the relevant target were part of the same perceptual group (i.e., both on the HUD or both on the runway) than when they were part of different perceptual groups. These results, as well as others, suggest that attentional constraints place severe limits on the ability of pilots to process HUD-referenced information and world-referenced information simultaneously. In addition, they provide direct evidence that transitioning from processing HUD information to processing world information requires an attention shift. Implications for HUD design are considered.

  8. Cognitive issues in head-up displays

    NASA Technical Reports Server (NTRS)

    Fischer, E.; Haines, R. F.

    1980-01-01

    The ability of pilots to recognize and act upon unexpected information, presented in either the outside world or in a head-up display (HUD), was evaluated. Eight commercial airline pilots flew 18 approaches with a flightpath-type HUD and 13 approaches with conventional instruments in a fixed-base 727 simulator. The approaches were flown under conditions of low visibility, turbulence, and wind shear. Vertical and lateral flight performance was measured for five cognitive variables: an unexpected obstacle on runway; vertical and lateral boresight-type offset of the HUD; lateral ILS beam bend-type offset; and no anomaly. Mean response time to the runway obstacle was longer with HUD than without it (4.13 vs 1.75 sec.), and two of the pilots did not see the obstacle at all with the HUD. None of the offsets caused any deterioration in lateral flight performance, but all caused some change in vertical tracking; all offsets seemed to magnify the environmental effects. In all conditions, both vertical and lateral tracking was better with the HUD than with the conventional instruments.

  9. Helmet-mounted displays for unmanned aerial vehicle control

    NASA Astrophysics Data System (ADS)

    Morphew, M. Ephimia; Shively, Jay R.; Casey, Daniel

    2004-09-01

    An experiment was performed to assess the effect of using a Helmet Mounted Display (HMD) versus a conventional computer monitor and joystick to perform an Unmanned Aerial Vehicle (UAV) sensor operator target search task. Eight subjects were evaluated on objective performance measures including their target detection accuracy and responses, in addition to subjective measures including workload, fatigue, situational awareness, and simulator sickness in both experimental conditions. Subjects were flown through a virtual world and asked to identify objects as targets, non-targets, or distractors. Results for objective measures indicated no difference in the operators' ability to accurately classify targets and non-targets. The subjects' ability to place the cursor on a target of interset (targeting accuracy), was, however, significantly better in the computer monitor condition than the HMD. The distance at which subjects could classify an object's identity was also significantly better in the computer monitor condition. Subjective measures showed no overall differences for sel-reported fatigue, workload, and situational awareness. A significant disadvantage, however, was found for the HMD with respect to self-reported nausea, disorientation, and oculomotor strain. Results are discussed in terms of their implications for the incorporation of HMDs into UAV ground control station operations.

  10. Spinal neurosurgery with the head-mounted "Varioscope" microscope.

    PubMed

    Kuchta, J; Simons, P

    2009-05-01

    We present a preliminary report on the intra-operative use of a head-mounted microscope ("Varioscope" Leica HM500) in spinal neurosurgery. The Varioscope is a dynamic microscope mounted on a head-set. It weights 297 g and measures 73 x 120 x 63 mm (length x width x height). It offers an infinitely variable range of magnification from 3.6x to 7.2x. The working distance ranges from 300 to 600 mm. The field of view varies between 30-144 mm, depending on the selected enlargement factor and the working distance. In addition to the zoom function, the device offers a focus function (automatic or on demand). The optical elements for focus and zoom are located in two separate tubes which are mounted on a middle section containing the mechanical components as well as the receiver unit for the focussing elements. The lenses are adjusted by means of motor-driven push/pull cables. The autofocus works well in larger operative fields and a working distance between 30 and 60 cm. Nevertheless, when used in today's "keyhole" approaches, the autofocus is not helpful when operating in deep structures. Based on the satisfactory results achieved in our series, we can recommend the Varioscope, especially when no stationary microscope is available. The portable device can be packed in a suitcase and can travel with the consultant microsurgeon to different hospitals and distant units. The built-in video camera is ideal for patients, staff, assistant surgeons, and student education with real-time video monitoring of procedures from the microsurgeon's perspective. For daily microsurgery, we felt more comfortable with fixed, stationary operating microscopes.

  11. Development of helmet-mounted display symbology for use as a primary flight reference

    NASA Astrophysics Data System (ADS)

    Jenkins, J. Chris

    2003-09-01

    The helmet-mounted display (HMD) will be used as the sole means of displaying head-up information to the pilot in future U.S. Air Force (USAF) fixed-wing tactical aircraft. For current fighter aircraft that employ the use of a stand-alone head-up display (HUD), the HMD will be integrated to provide the off-boresight symbology component of the head-up presentation. The symbology for on- and off-boresight use has to be designed to insure the effective interaction between display formats for conveyance of information to the pilot when transitioning between on- and off-boresight viewing angles. This is true for legacy aircraft where the symbology is presented in part by the HUD for on-boresight use with the HMD utilized for the off-boresight application and also for HUD-less aircraft, such as the Joint Strike Fighter, where symbology will be presented solely on the HMD. The Air Force Research Laboratory has been developing HMD symbology to meet the requirements to certify the HMD as a primary flight reference (PFR) for USAF fixed-wing tactical aircraft. This symbology has been designed to maximize the transference of attitude awareness to the pilot when switching between on- and off-boresight attitude references to help insure the pilot achieves correct awareness of spatial orientation. This paper describes the previous research that examined the ASAR for HUD applications, the design of the AFRL ASAR HUD symbology to replace the climb-dive ladder, and the planned flight test evaluation of the ASAR HUD for endorsement as a PFR.

  12. Latency Requirements for Head-Worn Display S/EVS Applications

    NASA Technical Reports Server (NTRS)

    Bailey, Randall E.; Trey Arthur, J. J., III; Williams, Steven P.

    2004-01-01

    NASA s Aviation Safety Program, Synthetic Vision Systems Project is conducting research in advanced flight deck concepts, such as Synthetic/Enhanced Vision Systems (S/EVS), for commercial and business aircraft. An emerging thrust in this activity is the development of spatially-integrated, large field-of-regard information display systems. Head-worn or helmet-mounted display systems are being proposed as one method in which to meet this objective. System delays or latencies inherent to spatially-integrated, head-worn displays critically influence the display utility, usability, and acceptability. Research results from three different, yet similar technical areas flight control, flight simulation, and virtual reality are collectively assembled in this paper to create a global perspective of delay or latency effects in head-worn or helmet-mounted display systems. Consistent definitions and measurement techniques are proposed herein for universal application and latency requirements for Head-Worn Display S/EVS applications are drafted. Future research areas are defined.

  13. Improved display optical performance with notch polarizers and specialized lamps for helmet-mounted display application

    NASA Astrophysics Data System (ADS)

    Heinze, Bill

    1996-06-01

    The helmet mounted display (HMD) is an important technology for aircraft cockpit information exchange, and is also of advantage for outdoor field use. For both applications, high display luminance is required to maintain acceptable contrast ratio while competing with environmental forward field scene luminance during bright daylight conditions. For the full color HMD, a broad color gamut is required. Notch Polarizers, made from crosslinked cholesteric liquid crystal silicones and utilized to modulate color with high resolution subtractive color twisted nematic diplay image sources, yield substantial improvements in system luminance efficiency, color gamut, and contrast ratio, compared with conventional color polarizers made with dichroic dyes. A TN subtractive color display system design with notch polarizers is presented, resulting in improved luminance, color gamut, contrast ratio, and contrast ratio in the presence of high ambient luminance. Results are given for backlighting with a broad band Xenon arc lamp, as well as with a trichrominance (primary color) lamp. Very substantial improvements in display system luminance efficiency, color gamut and contrast ratio were achieved.

  14. Applications of Augmented Vision Head-Mounted Systems in Vision Rehabilitation

    PubMed Central

    Peli, Eli; Luo, Gang; Bowers, Alex; Rensing, Noa

    2007-01-01

    Vision loss typically affects either the wide peripheral vision (important for mobility), or central vision (important for seeing details). Traditional optical visual aids usually recover the lost visual function, but at a high cost for the remaining visual function. We have developed a novel concept of vision-multiplexing using augmented vision head-mounted display systems to address vision loss. Two applications are discussed in this paper. In the first, minified edge images from a head-mounted video camera are presented on a see-through display providing visual field expansion for people with peripheral vision loss, while still enabling the full resolution of the residual central vision to be maintained. The concept has been applied in daytime and nighttime devices. A series of studies suggested that the system could help with visual search, obstacle avoidance, and nighttime mobility. Subjects were positive in their ratings of device cosmetics and ergonomics. The second application is for people with central vision loss. Using an on-axis aligned camera and display system, central visibility is enhanced with 1:1 scale edge images, while still enabling the wide field of the unimpaired peripheral vision to be maintained. The registration error of the system was found to be low in laboratory testing. PMID:18172511

  15. Head Up Displays. (Latest Citations from the Aerospace Database)

    NASA Technical Reports Server (NTRS)

    1997-01-01

    The bibliography contains citations concerning the design, fabrication, and applications of head up displays (HUDs). Applications include military aircraft, helicopters, space shuttle, and commercial aircraft. Functions of the display include instrument approach, target tracking, and navigation. The head up display provides for an integrated avionics system with the pilot in the loop. (Contains 50-250 citations and includes a subject term index and title list.)

  16. Head Up Displays. (Latest citations from the Aerospace Database)

    NASA Technical Reports Server (NTRS)

    1996-01-01

    The bibliography contains citations concerning the design, fabrication, and applications of head up displays (HUDs). Applications include military aircraft, helicopters, space shuttle, and commercial aircraft. Functions of the display include instrument approach, target tracking, and navigation. The head up display provides for an integrated avionics system with the pilot in the loop. (Contains 50-250 citations and includes a subject term index and title list.)

  17. System Would Generate Virtual Heads-Up Display

    NASA Technical Reports Server (NTRS)

    Lambert, James L.

    1994-01-01

    Proposed helmet-mounted electronic display system superimposes full-color alphanumerical and/or graphical information onto observer's visual field. Displayed information projected directly onto observer's retinas, giving observer illusion of full-size computer display in foreground or background. Display stereoscopic, holographic, or in form of virtual image. Used by pilots to view navigational information while looking outside or at instruments, by security officers to view information about critical facilities while looking at visitors, or possibly even stock-exchange facilities to view desktop monitors and overhead displays simultaneously. System includes acousto-optical tunable filter (AOTF), which acts as both spectral filter and spatial light modulator.

  18. Head-mounted spatial instruments II: Synthetic reality or impossible dream

    NASA Technical Reports Server (NTRS)

    Ellis, Stephen R.; Grunwald, Arthur

    1989-01-01

    A spatial instrument is defined as a spatial display which has been either geometrically or symbolically enhanced to enable a user to accomplish a particular task. Research conducted over the past several years on 3-D spatial instruments has shown that perspective displays, even when viewed from the correct viewpoint, are subject to systematic viewer biases. These biases interfere with correct spatial judgements of the presented pictorial information. The design of spatial instruments may not only require the introduction of compensatory distortions to remove the naturally occurring biases but also may significantly benefit from the introduction of artificial distortions which enhance performance. However, these image manipulations can cause a loss of visual-vestibular coordination and induce motion sickness. Consequently, the design of head-mounted spatial instruments will require an understanding of the tolerable limits of visual-vestibular discord.

  19. Optimizing a head-tracked stereo display system to guide hepatic tumor ablation.

    PubMed

    Fuchs, Henry; State, Andrei; Yang, Hua; Peck, Tabitha; Lee, Sang Woo; Rosenthal, Michael; Bulysheva, Anna; Burke, Charles

    2008-01-01

    Radio frequency ablation is a minimally invasive intervention that introduces -- under 2D ultrasound guidance and via a needle-like probe -- high-frequency electrical current into non-resectable hepatic tumors. These recur mostly on the periphery, indicating errors in probe placement. Hypothesizing that a contextually correct 3D display will aid targeting and decrease recurrence, we have developed a prototype guidance system based on a head-tracked 3D display and motion-tracked instruments. We describe our reasoning and our experience in selecting components for, designing and constructing the 3D display. Initial candidates were an augmented reality see-through head-mounted display and a virtual reality "fish tank" system. We describe the system requirements and explain how we arrived at the final decision. We show the operational guidance system in use on phantoms and animals.

  20. Basic Perception in Head-worn Augmented Reality Displays

    DTIC Science & Technology

    2012-01-01

    Head-worn displays have been an integral part of augmented reality since the inception of the field. However, due to numerous difficulties with...functions of the human visual system when using head-worn augmented reality displays. In particular, we look at loss of visual acuity and contrast (and...designing using such unique hardware, the perceptual capabilities of users suffer when looking at either the virtual or real portions of the augmented

  1. Human factors issues in the development of helmet-mounted displays for tactical fixed-wing aircraft

    NASA Astrophysics Data System (ADS)

    Barnaba, James M.

    1997-06-01

    There are many human factors issues that should be considered when designing a helmet mounted display for use in high speed aircraft with ejection seats. The Joint Helmet Mounted Cueing System Program Office, with support from the Armstrong Laboratory and the Naval Air Warfare Center, has been studying many of these issues and is able to report several findings in the areas of anthropometry, limitations in head movement, helmet stability under high gravity forces and mass properties. This paper serves to summarize the findings of the program office in these areas. The paper will include highlights of several studies that have involved anthropometric data manipulation, 3D head scans, and testing of manikin and human subjects in static and dynamic cockpit environment simulations.

  2. Binocular Rivalry and Attention in Helmet-Mounted Display Applications

    DTIC Science & Technology

    2007-02-01

    Hakkinen (2004) reported similar problems when a monocular HMD was used for a text-editing task. Finally, simulator sickness can occur when HMDs are worn... Hakkinen , J. (2004). A virtual display for mobile use. Society for Information Display International Symposium Digest of Technical Papers. Hollins

  3. Flight performance using a hyperstereo helmet-mounted display: post-flight debriefing questionnaire

    NASA Astrophysics Data System (ADS)

    Kalich, Melvyn E.; Rash, Clarence E.; Harding, Thomas H.; Jennings, Sion; Craig, Gregory; Stuart, Geoffrey W.

    2009-05-01

    Helmet-mounted display (HMD) designs have faced persistent head-supported mass and center of mass (CM) problems, especially HMD designs like night vision goggles (NVG) that utilize image intensification (I2) sensors mounted forward in front of the user's eyes. Relocating I2 sensors from the front to the sides of the helmet, at or below the transverse plane through the user's head CM, can resolve most of the CM problems. However, the resulting increase in the separation between the two I2 channels effectively increases the user's interpupillary distance (IPD). This HMD design is referred to as a hyperstero design and introduces the phenomenon of hyperstereopsis, a type of visual distortion where stereoscopic depth perception is exaggerated, particularly at distances under 200 feet (~60 meters). The presence of hyperstereopsis has been a concern regarding implementation of hyperstereo HMDs for rotary-wing aircraft. To address this concern, a flight study was conducted to assess the impact of hyperstereopsis on aircraft handling proficiency and pilot acceptance. Three rated aviators with differing levels of I2 and hyperstereo HMD experience conducted a series of flights that concentrated on low-level maneuvers over a two-week period. Initial and final flights were flown with a standard issue I2 device and a production hyperstereo design HMD. Interim flights were flown only with the hyperstereo HMD. Two aviators accumulated 8 hours of flight time with the hyperstereo HMD, while the third accumulated 6.9 hours. This paper presents data collected via written questionnaires completed by the aviators during the post-flight debriefings. These data are compared to questionnaire data from a previous flight investigation in which aviators in a copilot capacity, hands not on the flight controls, accumulated 8 flight hours of flight time using a hyperstereo HMD.

  4. Head-Up Display (HUD) Technology Demonstration.

    DTIC Science & Technology

    1983-07-01

    Figure No. Page 39 Gain versus viewing angle for two screen materials........... 70 40 Image brightness uniformity with and without fresnel lenses ....... ......................... ....... ... .... . 72...discontinuity must be avoided. The solution to four-module display uniformity problem is accomplished with the use of four aligned fresnel lenses . The...The effect of the fresnel lenses on screen performance is shown in Figure 40-c and -d. The brightness nonuniformity caused by the directional properties

  5. The use of optical waveguides in head up display (HUD) applications

    NASA Astrophysics Data System (ADS)

    Homan, Malcolm

    2013-06-01

    The application of optical waveguides to Head Up Displays (HUD) is an enabling technology which solves the critical issues of volume reduction (including cockpit intrusion) and mass reduction in an affordable product which retains the high performance optical capabilities associated with today's generation of digital display based HUDs. Improved operability and pilot comfort is achieved regardless of the installation by virtue of the intrinsic properties of optical waveguides and this has enabled BAE Systems Electronic Systems to develop two distinct product streams for glareshield and overhead HUD installations respectively. This paper addresses the design drivers behind the development of the next generation of Head Up Displays and their compatibility with evolving cockpit architectures and structures. The implementation of large scale optical waveguide combiners capable of matching and exceeding the display performances normally only associated with current digital display sourced HUDs has enabled BAE Systems Electronic Systems to solve the volume and installation challenges of the latest military and civil cockpits with it's LiteHUD® technology. Glareshield mounted waveguide based HUDs are compatible with the trend towards the addition of Large Area Displays (LAD) in place of the traditional multiple Head Down Displays (HDD) within military fast jet cockpits. They use an "indirect view" variant of the display which allows the amalgamation of high resolution digital display devices with the inherently small volume and low mass of the waveguide optics. This is then viewed using the more traditional technology of a conventional HUD combiner. This successful combination of technologies has resulted in the LPHUD product which is specifically designed by BAE Systems Electronic Systems to provide an ultra-low profile HUD which can be installed behind a LAD; still providing the level of performance that is at least equivalent to that of a conventional large volume

  6. In-flight evaluation of a fiber optic helmet-mounted display

    NASA Astrophysics Data System (ADS)

    Jennings, Sion A.; Gubbels, Arthur W.; Swail, Carl P.; Craig, Greg

    1998-08-01

    The National Research Council of Canada (NRC), in conjunction with the Canadian Department of National Defence (DND), is investigating the use of helmet-mounted displays (HMD) to improve pilot situational awareness in all-weather search and rescue helicopter operations. The National Research Council has installed a visually coupled HMD system in the NRC Bell 205 Airborne Simulator. Equipped with a full authority fly-by-wire control system, the Bell 205 has variable stability characteristics, which makes the airborne simulator the ideal platform for the integrated flight testing of HMDs in a simulated operational environment. This paper presents preliminary results from flight test of the NRC HMD. These results are in the form of numerical head tracker data, and subjective handling qualities ratings. Flight test results showed that the HMD degraded handling qualities due to reduced acuity, limited field-of-view, time delays in the sensor platform, and fatigue caused by excessive helmet inertia. Some evidence was found to support the hypothesis of an opto-kinetic cervical reflex whereby a pilot pitches and rolls his head in response to aircraft movements to maintain a level horizon in their field-of- view.

  7. Binocular Rivalry in Helmet-Mounted Display Applications

    DTIC Science & Technology

    1975-06-01

    Function and Visual Acuity .Threshold for 0. I-percent Transmittance See- Through Display and 4000-foot Lambert Ambient ...... 107 37 Modulation...Transfer Function and Visual Acuity Threshold for ’. 0-percent Transmittance See- Through Disp l.y and 4000-foot Lambert Ambient ...... i08 38 Modulation...Transfer Function and Visual Acuity Threshold for 10.0-percent Transmittance See- Through Display and 4000-foot Lambert Ambient ........ 109 39

  8. Design for an Improved Head-Mounted Display System

    DTIC Science & Technology

    2007-11-02

    mechanical properties from -40ºF up to temperatures of 356ºF. It is radiation-resistant and is naturally flame- retardant. Glass reinforced grades have...STTR project, managed the HMD production program for n-vision to deliver more than 100 systems to Disney Regional Entertainment for their DisneyQuest...medical visualization, research, and entertainment and the customer base included Lockheed, Raytheon, Boeing, BMW, DaimlerChrysler, Volvo, NASA, Walt

  9. Psychometric Assessment of Stereoscopic Head-Mounted Displays

    DTIC Science & Technology

    2016-06-29

    operationally relevant rotary wing call-to-landing task to research the applicability of U.S. Air Force Flying Class III depth perception standards...landing task to research the applicability of U.S. Air Force Flying Class III depth perception standards. Prior to performing this research, an...program implemented a unique three-dimensional (3D) immersive environment to evaluate the applicability of USAF depth perception standards for non

  10. Effects of aircraft windscreen on helmet-mounted display/tracker aiming accuracy

    NASA Astrophysics Data System (ADS)

    Task, H. Lee

    1996-06-01

    Modern fighter aircraft windscreens are typically made of curved, transparent plastic for improved aero-dynamics and bird-strike protection. Since they are curved these transparencies often refract light in such a way that a pilot looking through the transparency will see a target in a location other than where it really is. This effect has been known for many years and methods to correct the aircraft head-up display (HUD) for these angular deviations have been developed and employed. The same problem will occur for helmet-mounted displays (HMDs) used for target acquisition only worse due to the fact the pilot can look through any part of the transparency instead of being constrained to just the forward section as in the case of the HUD. To determine the potential impact of these windscreen refraction errors two F-15 windscreens were measured; one acrylic and one multilayer acrylic and polycarbonate laminate. The average aiming error measured for the acrylic was 3.6 milliradians with a maximum error of 9.0 milliradians. The laminated windscreen was slightly worse at 4.1 milliradians average error and 10.5 milliradians maximum. These aiming errors were greatly reduced by employing correction algorithms which could be applied to the aiming information on the HMD. Subtleties of coordinate systems and roll correction are also addressed.

  11. An Analysis of Eye Movements with Helmet Mounted Displays

    DTIC Science & Technology

    2014-03-27

    method for off-boresight targeting on fighter aircraft (7). Advancements in HMD capabilities have expanded their use into many application areas, such...a high resolution IR sensitive camera will be used to image these LEDs. This imagery will be used to determine absolute head position in the x and z...movements to develop a method to understand the source of the unintended eye movements. Through the use of Electro-Oculography (EOG) eye movements were

  12. Emergence of solid state helmet-mounted displays in military applications

    NASA Astrophysics Data System (ADS)

    Casey, Curtis J.

    2002-08-01

    Helmet Mounted Displays (HMDs) are used to provide pilots with out-the-window capabilities for engaging tactical threats. The first modern system to be employed was the Apache Integrated Helmet Display Sighting System (IHADSS). Using an optical tracker and multiple sensors, the pilot is able to navigate and engage the enemy with his weapons systems cued by the HMD in day and night conditions. Over the next several years HMDs were tested on tactical jet aircraft. The tactical fighter environment - high G maneuvering and the possibility of ejection - created several problems regarding integration and head-borne weight. However, these problems were soon solved by American, British, Israeli, and Russian companies and are employed or in the process of employment aboard the respective countries' tactical aircraft. It is noteworthy that the current configuration employs both the Heads-Up Display (HUD) as well as the HMD. The new Joint Strike Fighter (JSF), however, will become the first tactical jet to employ only a HMD. HMDs have increasingly become part of the avionics and weapons systems of new aircraft and helicopter platforms. Their use however, is migrating to other military applications. They are currently under evaluation on Combat Vehicle platforms for driving tasks to target acquisition and designation tasks under near-all weather, 24-hour conditions. Their use also has penetrated the individual application such as providing data and situational awareness to the individual soldier; the U.S. Army's Land Warrior Program is an example of this technology being applied. Current HMD systems are CRT-based and have many short-comings, including weight, reliability. The emergence of new microelectronics and solid state image sources - Flat Panel Displays (FPDs) - however, has expanded the application of vision devices across all facets of military applications. Some of the greatest contributions are derived from the following Enabling Technologies, and it is upon those

  13. Flight performance using a hyperstereo helmet-mounted display: aircraft handling

    NASA Astrophysics Data System (ADS)

    Jennings, Sion A.; Craig, Gregory L.; Stuart, Geoffrey W.; Kalich, Melvyn E.; Rash, Clarence E.; Harding, Thomas H.

    2009-05-01

    A flight study was conducted to assess the impact of hyperstereopsis on helicopter handling proficiency, workload and pilot acceptance. Three pilots with varying levels of night vision goggle and hyperstereo helmet-mounted display experience participated in the test. The pilots carried out a series of flights consisting of low-level maneuvers over a period of two weeks. Four of the test maneuvers, The turn around the tail, the hard surface landing, the hover height estimation and the tree-line following were analysed in detail. At the end of the testing period, no significant difference was observed in the performance data, between maneuvers performed with the TopOwl helmet and maneuvers performed with the standard night vision goggle. This study addressed only the image intensification display aspects of the TopOwl helmet system. The tests did not assess the added benefits of overlaid symbology or head slaved infrared camera imagery. These capabilities need to be taken into account when assessing the overall usefulness of the TopOwl system. Even so, this test showed that pilots can utilize the image intensification imagery displayed on the TopOwl to perform benign night flying tasks to an equivalent level as pilots using ANVIS. The study should be extended to investigate more dynamic and aggressive low level flying, slope landings and ship deck landings. While there may be concerns regarding the effect of hyperstereopsis on piloting, this initial study suggests that pilots can either adapt or compensate for hyperstereo effects with sufficient exposure and training. Further analysis and testing is required to determine the extent of training required.

  14. Three dimensional audio versus head down TCAS displays

    NASA Technical Reports Server (NTRS)

    Begault, Durand R.; Pittman, Marc T.

    1994-01-01

    The advantage of a head up auditory display was evaluated in an experiment designed to measure and compare the acquisition time for capturing visual targets under two conditions: Standard head down traffic collision avoidance system (TCAS) display, and three-dimensional (3-D) audio TCAS presentation. Ten commercial airline crews were tested under full mission simulation conditions at the NASA Ames Crew-Vehicle Systems Research Facility Advanced Concepts Flight Simulator. Scenario software generated targets corresponding to aircraft which activated a 3-D aural advisory or a TCAS advisory. Results showed a significant difference in target acquisition time between the two conditions, favoring the 3-D audio TCAS condition by 500 ms.

  15. First Use of Heads-up Display for Astronomy Education

    NASA Astrophysics Data System (ADS)

    Mumford, Holly; Hintz, E. G.; Jones, M.; Lawler, J.; Fisler, A.

    2013-01-01

    As part of our work on deaf education in a planetarium environment we are exploring the use of heads-up display systems. This allows us to overlap an ASL interpreter with our educational videos. The overall goal is to allow a student to watch a full-dome planetarium show and have the interpreter tracking to any portion of the video. We will present the first results of using a heads-up display to provide an ASL ‘sound-track’ for a deaf audience. This work is partially funded by an NSF IIS-1124548 grant and funding from the Sorenson Foundation.

  16. Exaggerated displays do not improve mounting success in male seaweed flies Fucellia tergina (Diptera: Anthomyiidae).

    PubMed

    Memmott, Ruth; Briffa, Mark

    2015-11-01

    Signals of individual quality are assumed to be difficult to exaggerate, either because they are directly linked to underlying traits (indices) or because they are costly to perform (handicaps). In practise advertisement displays may consist of conventional and costly components, for instance where a morphological structure related to body size is used in visual displays. In this case, there is the potential for dishonest displays, due to the population level variance around the relationship between body size and display structures. We examine the use of wing flicking displays that we observed in situ in a strandline dwelling seaweed fly Fucellia tergina, using overall body size and the size of their eyes as underlying indicators of condition. Males displayed far more frequently than females, and were also observed to frequently mount other flies, a behaviour that was rare in females. The rate of display was greater for males that had positive residual values from relationships between wing length and body length. In other words those males with larger than expected wings for their underlying quality displayed more frequently, indicating that these displays are open to exaggeration. Males with larger than expected wings (for the size of their body or eyes), however, mounted less frequently. We suggest that small bodied males are less successful in terms of mounting, but that those small males with relatively large wings may attempt to compensate for this through increased display effort.

  17. Head tracking for viewpoint control in stereographic displays

    NASA Astrophysics Data System (ADS)

    Browse, Roger A.; Rodger, James C.; Pakowski, Sarah; Davis, Jennifer M.

    1999-05-01

    Future computer interfaces will likely use 3D displays with stereographic viewing to take advantage of the increased information inherent in 3D. The appropriate roles of devices to manipulate 3D displays, including the mouse, joystick and head tracking remain unresolved. Our research centers on the use of head tracking for the control of perspective. For monoscopic viewing, we previously found that viewers can control displays effectively with head movements. They learn rapidly to use head movements, though scene adjustments amplify or even reverse natural perspective changes, and this ability persist over time. With stereo viewing, if head movements do ont produce the expected change in perspective, the viewer may be confused, reducing the effectiveness of head tracking. We tested these conjectures in the experiment reported here, establishing the extent to which the flexibility found under monoscopic viewing extends to stereo. As in previous experiments, the viewer makes head movements to see a target sphere through a ring positioned in virtual space between the viewer and the target. We used a variety of ring sizes and position to measure the speed and directness of movement under four conditions that varied the scene location in depth, plus the extent and direction of perspective change. These combinations permit us to evaluate the effects of direction and extent of scene adjustment on viewers' ability to use head movements to alter virtual viewpoint. While we found no difference for reversed adjustments under monoscopic viewing, these conditions appear more difficult in stereo viewing. Furthermore, viewers perform better when perspective changes are amplified.

  18. Integrated head package for top mounted nuclear instrumentation

    DOEpatents

    Malandra, Louis J.; Hornak, Leonard P.; Meuschke, Robert E.

    1993-01-01

    A nuclear reactor such as a pressurized water reactor has an integrated head package providing structural support and increasing shielding leading toward the vessel head. A reactor vessel head engages the reactor vessel, and a control rod guide mechanism over the vessel head raises and lowers control rods in certain of the thimble tubes, traversing penetrations in the reactor vessel head, and being coupled to the control rods. An instrumentation tube structure includes instrumentation tubes with sensors movable into certain thimble tubes disposed in the fuel assemblies. Couplings for the sensors also traverse penetrations in the reactor vessel head. A shroud is attached over the reactor vessel head and encloses the control rod guide mechanism and at least a portion of the instrumentation tubes when retracted. The shroud forms a structural element of sufficient strength to support the vessel head, the control rod guide mechanism and the instrumentation tube structure, and includes radiation shielding material for limiting passage of radiation from retracted instrumentation tubes. The shroud is thicker at the bottom adjacent the vessel head, where the more irradiated lower ends of retracted sensors reside. The vessel head, shroud and contents thus can be removed from the reactor as a unit and rested safely and securely on a support.

  19. Transfer alignment from a personal locator system to a handheld or head-mounted instrument

    NASA Astrophysics Data System (ADS)

    Ojeda, Lauro; Borenstein, Johann

    2011-06-01

    This paper presents a method for computing position and attitude of an instrument attached to the human body such as a handheld or head-mounted video camera. The system uses two Inertial Measurement Units (IMUs). One IMU is part of our earlier-developed Personal Dead-Reckoning (PDR) system, which tracks the position and heading of a walking person relative to a known starting position. The other IMU is rigidly attached to the handheld or head-mounted instrument. Our existing PDR system is substantially more accurate than conventional IMU-based systems because the IMU is mounted on the foot of the user where error correction techniques can be applied that are unavailable for IMUs mounted anywhere else on the body. However, if the walker is waving a handheld or head-mounted instrument, the position and attitude of the instrument is not known. Equipping the instrument with an additional IMU is by itself an unsatisfactory solution because that IMU is subject to accelerometer and gyro drift, which, unlike in the case of the foot-mounted IMU, cannot be corrected and cause unbounded position and heading errors. Our approach uses transfer alignment techniques and takes advantage of the fact that the handheld IMU moves with the walker. This constraint is used to bound and correct errors by a Kalman filter. The paper explains our method and presents extensive experimental results. The results show up to a five-fold reduction in heading errors for the handheld IMU.

  20. Time Counts! Some Comments on System Latency in Head-Referenced Displays

    NASA Technical Reports Server (NTRS)

    Ellis, Stephen R.; Adelstein, Bernard D.

    2013-01-01

    System response latency is a prominent characteristic of human-computer interaction. Laggy systems are; however, not simply annoying but substantially reduce user productivity. The impact of latency on head referenced display systems, particularly head-mounted systems, is especially disturbing since not only can it interfere with dynamic registration in augmented reality displays but it also can in some cases indirectly contribute to motion sickness. We will summarize several experiments using standard psychophysical discrimination techniques that suggest what system latencies will be required to achieve perceptual stability for spatially referenced computer-generated imagery. In conclusion I will speculate about other system performance characteristics that I would hope to have for a dream augmented reality system.

  1. Critical testing for helmet-mounted displays: a tracking system accuracy test for the joint helmet mounted cueing system

    NASA Astrophysics Data System (ADS)

    Renner, Adam P.

    2012-06-01

    Helmet mounted displays have not been supported with adequate methods and materials to validate and verify the performance of the underlying tracking systems when tested in a simulated or operational environment. Like most electronic systems on aircraft, HMDs evolve over the lifecycle of the system due to requirements changes or diminishing manufacturing sources. Hardware and software bugs are often introduced as the design evolves and it is necessary to revalidate a systems performance attributes over the course of these design changes. An on-aircraft test has been developed and refined to address this testing gap for the Joint Helmet Mounted Cueing System (JHMCS) on F-16 aircraft. This test can be readily ported to other aircraft systems which employ the JHMCS, and has already been ported to the F-18. Additionally, this test method could provide an added value in the testing of any HMD that requires accurate cueing, whether used on fixed or rotary wing aircraft.

  2. MicroDisplay technology: from eyeglass-mounted displays to portable projectors to the Dick Tracy video phone

    NASA Astrophysics Data System (ADS)

    Alvelda, Phillip

    1997-06-01

    MicroDisplay devices are based on a combination of technologies ranging from the extreme integration capability of conventionally fabricated CMOS active-matrix liquid crystal display substrates to proprietary tunable color- filter technology, to optical distortion correction technology for lens-system compensation. All of these technologies were devised to create a line of application- specific integrated circuit single-chip display devices with integrated computing, memory, and communication circuitry. Next-generation portable communication, computer, and consumer electronic devices such as truly portable monitor and TV projectors, eyeglass-clip-on virtual displays, pagers and personal communication services hand-sets, and wristwatch-mounted video phones are all target markets for MicroDisplay technology.

  3. Pathway Concepts Experiment for Head-Down Synthetic Vision Displays

    NASA Technical Reports Server (NTRS)

    Prinzel, Lawrence J., III; Arthur, Jarvis J., III; Kramer, Lynda J.; Bailey, Randall E.

    2004-01-01

    Eight 757 commercial airline captains flew 22 approaches using the Reno Sparks 16R Visual Arrival under simulated Category I conditions. Approaches were flown using a head-down synthetic vision display to evaluate four tunnel ("minimal", "box", "dynamic pathway", "dynamic crow s feet") and three guidance ("ball", "tadpole", "follow-me aircraft") concepts and compare their efficacy to a baseline condition (i.e., no tunnel, ball guidance). The results showed that the tunnel concepts significantly improved pilot performance and situation awareness and lowered workload compared to the baseline condition. The dynamic crow s feet tunnel and follow-me aircraft guidance concepts were found to be the best candidates for future synthetic vision head-down displays. These results are discussed with implications for synthetic vision display design and future research.

  4. Pathway concepts experiment for head-down synthetic vision displays

    NASA Astrophysics Data System (ADS)

    Prinzel, Lawrence J., III; Arthur, Jarvis J., III; Kramer, Lynda J.; Bailey, Randall E.

    2004-08-01

    Eight 757 commercial airline captains flew 22 approaches using the Reno Sparks 16R Visual Arrival under simulated Category I conditions. Approaches were flown using a head-down synthetic vision display to evaluate four tunnel ("minimal", "box", "dynamic pathway", "dynamic crow's feet") and three guidance ("ball", "tadpole", "follow-me aircraft") concepts and compare their efficacy to a baseline condition (i.e., no tunnel, ball guidance). The results showed that the tunnel concepts significantly improved pilot performance and situation awareness and lowered workload compared to the baseline condition. The dynamic crow's feet tunnel and follow-me aircraft guidance concepts were found to be the best candidates for future synthetic vision head-down displays. These results are discussed with implications for synthetic vision display design and future research.

  5. Contributions of Head-Mounted Cameras to Studying the Visual Environments of Infants and Young Children

    ERIC Educational Resources Information Center

    Smith, Linda B.; Yu, Chen; Yoshida, Hanako; Fausey, Caitlin M.

    2015-01-01

    Head-mounted video cameras (with and without an eye camera to track gaze direction) are being increasingly used to study infants' and young children's visual environments and provide new and often unexpected insights about the visual world from a child's point of view. The challenge in using head cameras is principally conceptual and concerns the…

  6. Head Worn Display System for Equivalent Visual Operations

    NASA Technical Reports Server (NTRS)

    Cupero, Frank; Valimont, Brian; Wise, John; Best. Carl; DeMers, Bob

    2009-01-01

    Head-Worn Displays or so-called, near-to-eye displays have potentially significant advantages in terms of cost, overcoming cockpit space constraints, and for the display of spatially-integrated information. However, many technical issues need to be overcome before these technologies can be successfully introduced into commercial aircraft cockpits. The results of three activities are reported. First, the near-to-eye display design, technological, and human factors issues are described and a literature review is presented. Second, the results of a fixed-base piloted simulation, investigating the impact of near to eye displays on both operational and visual performance is reported. Straight-in approaches were flown in simulated visual and instrument conditions while using either a biocular or a monocular display placed on either the dominant or non-dominant eye. The pilot's flight performance, visual acuity, and ability to detect unsafe conditions on the runway were tested. The data generally supports a monocular design with minimal impact due to eye dominance. Finally, a method for head tracker system latency measurement is developed and used to compare two different devices.

  7. Head-Worn Displays for NextGen

    NASA Technical Reports Server (NTRS)

    Bailey, Randall E.; Shelton, Kevin J.; Arthur, J. J.

    2011-01-01

    The operating concepts emerging under the Next Generation air transportation system (NextGen) require new technology and procedures - not only on the ground-side - but also on the flight deck. Flight deck display and decision support technologies are specifically targeted to overcome aircraft safety barriers that might otherwise constrain the full realization of NextGen. One such technology is the very lightweight, unobtrusive head-worn display (HWD). HWDs with an integrated head-tracking system are being researched as they offer significant potential benefit under emerging NextGen operational concepts. Two areas of benefit for NextGen are defined. First, the HWD may be designed to be equivalent to the Head-Up Display (HUD) using Virtual HUD concepts. As such, these operational credits may be provided to significantly more aircraft for which HUD installation is neither practical nor possible. Second, the HWD provides unique display capabilities, such as an unlimited field-of-regard. These capabilities may be integral to emerging NextGen operational concepts, eliminating safety issues which might otherwise constrain the full realization of NextGen. The paper details recent research results, current HWD technology limitations, and future technology development needed to realize HWDs as a enabling technology for NextGen.

  8. AMLCD head-down displays for avionic applications

    NASA Astrophysics Data System (ADS)

    Davis, Alan J.

    1997-02-01

    Smiths Industries has been involved in the design, manufacture and supply of products used for the presentation of information, in one form or another, from its early pioneering years through to the present day. In the mid 1980s Smiths Industries began to invest in the then emerging active matrix liquid crystal display (AMLCD) technology which the company believed would eventually take over from the cathode ray tube. To date Smiths Industries has made a significant investment in acquiring the enabling technology needed to produce active matrix liquid crystal color head- down displays for fast jet, helicopter and civil aircraft applications. The significant improvement in AMLCD product quality and manufacturing capability over recent years has enabled market penetration of AMLCD technology products to be achieved in military and civil avionic markets. Virtually all new contracts for head-down displays are now demanding the use of AMLCD technology rather than the cathode ray tube. A significant decision to move to AMLCD technology was made by McDonnell Douglas Helicopters in 1995, when a contract to supply over 4000 head-down display products for the Apache Helicopter was let. This has paved the way for the future of AMLCD technology.

  9. Integration, development, and qualification of the helmet-mounted sight and display on the Rooivalk Attack Helicopter

    NASA Astrophysics Data System (ADS)

    Mace, Timothy K.; Van Zyl, Petrus H.; Cross, Trevor

    2001-08-01

    The Rooivalk Attack Helicopter is designed and manufactured by Denel Aviation of South Africa, and in service with the South African Air Force. The Helmet Mounted Sight and Display (HMSD) hardware is manufactured by Sextant Avionique of France. The HMSD symbology is developed by Denel Aviation and is specific to the weapons and roles of the aircraft. The HMSD has visor projected NVG and PNVS images, and Flight and Weapon Symbology incorporating head slaved weapon aiming, helmet-to-helmet cueing, and helmet to main sight cueing. The NVG/PNVS image selection and main image controls are incorporated in the flight controls. The paper gives an overview of the aircraft visionic design and describes the integration process. The development of the displayed flight and weapon symbols is discussed. Aeronautical Design Standard 33E was chosen as a basis for the qualification process, and the development of the qualification criteria and the flight testing program are discussed.

  10. An experimental evaluation of head-up display formats

    NASA Technical Reports Server (NTRS)

    Naish, J. M.; Miller, D. L.

    1980-01-01

    Three types of head-up display format are investigated. Type 1 is an unreferenced (conventional) flight director, type 2 is a ground referenced flight path display, and type 3 is a ground referenced director. Formats are generated by computer and presented by reflecting collimation against a simulated forward view in flight. Pilots, holding commercial licenses, fly approaches in the instrument flight mode and in a combined instrument and visual flight mode. The approaches are in wind shear with varied conditions of visibility, offset, and turbulence. The displays are equivalent in pure tracking but there is a slight advantage for the unreferenced director in poor conditions. Flight path displays are better for tracking in the combined flight mode, possibly because of poor director control laws and the division of attention between superimposed fields. Workloads is better for the type 2 displays. The flight path and referenced director displays are criticized for effects of symbol motion and field limiting. In the subjective judgment of pilots familiar with the director displays, they are rated clearly better than path displays, with a preference for the unreferenced director. There is a fair division of attention between superimposed fields.

  11. Experimental testing of flight control head up displays

    NASA Technical Reports Server (NTRS)

    Berjal, M.

    1978-01-01

    Experiments and tests with 4 generations of head up displays was reported. The CV 191, based on fighter aircraft gunsights was replaced by the CV 193, with several improvements. The CV 193 V incorporates the velocity vector reference mark, eliminates much other data, clusters the rest in a small area of the visual field and is seen together with the outside landscape. The CV 91 presents only velocity vector and total angle of descent data, used when runway and horizon are visible; TC 121 displays an outline of the runway and can be used in visual and instrument approaches.

  12. Astronauts Gibson and Pogue at Apollo Telescope Mount display/control panel

    NASA Technical Reports Server (NTRS)

    1973-01-01

    Scientist-Astronaut Edward G. Gibson, seated, and Astronaut William R. Pogue discuss a mission procedure at the Apollo Telescope Mount (ATM) display and control panel mockup in the one-G trainer for the Multiple Docking Adapter (MDA) at JSC.

  13. Ownship status helmet-mounted display symbology for off-boresight tactical applications

    NASA Astrophysics Data System (ADS)

    Jenkins, J. Chris; Thurling, Andrew J.; Brown, Becky D.

    2003-09-01

    Ownship status helmet-mounted display (HMD) symbology for off-boresight use in fixed-wing tactical aircraft serves to convey aircraft state information (e.g., airspeed, heading, altitude, and attitude) to the pilot for increased situation awareness and maintenance of spatial orientation. A recent flight test evaluation of HMD symbology conducted by the Air Force Research Laboratory (AFRL) and the Edwards AFB Test Pilot School (TPS) indicated a clear performance advantage afforded by the use of off-boresight symbology compared to HUD use alone. The results indicated that the Non-Distributed Flight Reference (NDFR) was the best format of the HMD symbol sets evaluated and served as a good information/orientation aid off-boresight but needs further development to realize its tactical benefit. Specifically, the TPS recommendations pointed to a need for an improved rate-of-change (i.e., trend) indicator for airspeed and altitude, as well as an improvement to the off-boresight attitude reference concerning attitude precision (i.e., climb-dive), particularly near straight and level flight. Based on these recommendations, AFRL modified the original design of the NDFR symbology to satisfy the deficiencies noted by the Edwards AFB TPS. Two variants of the NDFR format with modifications for conveying trend information for airspeed and altitude as well as precision of aircraft attitude were evaluated along with the Mil-Std-1787D HUD symbology and baseline NDFR format. The study examined the four symbol sets during two simulated operationally representative air-to-air intercept tasks that employed the use of an HMD for the off-boresight visual acquisition of a target aircraft. Overall, the NDFR/Odometer symbology allowed a significantly higher amount of off-boresight viewing time while equaling the HUD and other off-boresight symbol sets for primary task performance and proved to be the preferred format for trend mechanization based on pilot comments.

  14. [A case of hypothyroidism displaying "dropped head" syndrome].

    PubMed

    Furutani, Rikiya; Ishihara, Kenji; Miyazawa, Yumi; Suzuki, Yoshio; Shiota, Jun-Ichi; Kawamur, Mitsuru

    2007-01-01

    We describe a patient with hypothyroidism displaying "dropped head" syndrome. A 50-year-old man visited our clinic because he was unable to hold his head in the natural position. He had weakness and hypertrophy of the neck extensor muscles. Tendon reflexes were diminished or absent in all limbs. Mounding phenomena were observed in the bilateral upper extremities. Blood biochemical analysis revealed hypothyroidism, hyperlipidemia, and elevated levels of muscle-derived enzymes. Magnetic resonance imaging (MRI) of the neck demonstrated swelling and hyperintensity of the neck extensor muscles on T2-weighted images. The result of biopsy of the right biceps brachii muscle suggested mild atrophy of type 2 fibers. The diameters of the muscle fibers exhibited mild variation. No inflammatory changes were observed. We diagnosed hin as having "dropped head" syndrome due to hypothyroidism. Administration of thyroid hormone agent gradually improved his condition, and he became able to hold his head in the natural position. Levels of muscle-derived enzymes normalized and his hyperlipidemia remitted. Neck MRI also revealed improvement. Our findings suggest that hypothyroidism should be considered in the differential diagnosis of "dropped head" syndrome, although only a few cases like ours have been reported.

  15. Contributions of head-mounted cameras to studying the visual environments of infants and young children

    PubMed Central

    Smith, Linda; Yu, Chen; Yoshida, Hanako; Fausey, Caitlin M.

    2014-01-01

    Head-mounted video cameras (with and without an eye camera to track gaze direction) are being increasingly used to study infants’ and young children’s visual environments and provide new and often unexpected insights about the visual world from a child’s point of view. The challenge in using head cameras is principally conceptual and concerns the match between what these cameras measure and the research question. Head cameras record the scene in front of faces and thus answer questions about those head-centered scenes. In this “tools of the trade” article, we consider the unique contributions provided by head-centered video, the limitations and open questions that remain for head-camera methods, and the practical issues of placing head-cameras on infants and analyzing the generated video. PMID:26257584

  16. Contributions of head-mounted cameras to studying the visual environments of infants and young children.

    PubMed

    Smith, Linda; Yu, Chen; Yoshida, Hanako; Fausey, Caitlin M

    Head-mounted video cameras (with and without an eye camera to track gaze direction) are being increasingly used to study infants' and young children's visual environments and provide new and often unexpected insights about the visual world from a child's point of view. The challenge in using head cameras is principally conceptual and concerns the match between what these cameras measure and the research question. Head cameras record the scene in front of faces and thus answer questions about those head-centered scenes. In this "tools of the trade" article, we consider the unique contributions provided by head-centered video, the limitations and open questions that remain for head-camera methods, and the practical issues of placing head-cameras on infants and analyzing the generated video.

  17. Consideration of technologies for head-down displays

    NASA Astrophysics Data System (ADS)

    Bartlett, Christopher T.

    1998-09-01

    The market for military avionics head down displays for which Active Matrix Liquid Crystal Displays (AMLCD) has been specified is both well established and substantial. Typical major programs such as F-22, V-22 and Joint Strike Fighter (JSF) amount to over 15,000 displays. Nevertheless there is an insecurity about the situation because of the dependency upon Japanese and Korean manufacturers and the vagaries of the commercial market. The U.S. has only 7% of the world's manufacturing capability in AMLCD and is seeking alternative technologies to regain a hold in this lucrative business. The U.S. military manufacturers of AMLCD are capable, but can never achieve the benefits of scale that Commercial Off The Shelf (COTS) equipment can offer. In addition to the commercial and political concerns, there are still performance issues related to AMLCD and there is a view that emissive displays in particular can offer advantages over AMLCD. However, it is beneficial to be able to tailor display sizes and there are doubts about the ability of current flat panel technologies to achieve custom, or indeed large area panels either economically, or reliably. It is in this arena that projection displays may be the optimum solution.

  18. Terrain Portrayal for Head-Down Displays Experiment

    NASA Technical Reports Server (NTRS)

    Hughes, Monica F.; Takallu, M. A.

    2002-01-01

    The General Aviation Element of the Aviation Safety Program's Synthetic Vision Systems (SVS) Project is developing technology to eliminate low visibility induced General Aviation (GA) accidents. SVS displays present computer generated 3-dimensional imagery of the surrounding terrain on the Primary Flight Display (PFD) to greatly enhance pilot's situation awareness (SA), reducing or eliminating Controlled Flight into Terrain, as well as Low-Visibility Loss of Control accidents. SVS-conducted research is facilitating development of display concepts that provide the pilot with an unobstructed view of the outside terrain, regardless of weather conditions and time of day. A critical component of SVS displays is the appropriate presentation of terrain to the pilot. An experimental study has been conducted at NASA Langley Research Center (LaRC) to explore and quantify the relationship between the realism of the terrain presentation and resulting enhancements of pilot SA and pilot performance. Composed of complementary simulation and flight test efforts, Terrain Portrayal for Head-Down Displays (TP-HDD) experiments will help researchers evaluate critical terrain portrayal concepts. The experimental effort is to provide data to enable design trades that optimize SVS applications, as well as develop requirements and recommendations to facilitate the certification process. This paper focuses on the experimental set-up and preliminary qualitative results of the TP-HDD simulation experiment. In this experiment a fixed based flight simulator was equipped with various types of Head Down flight displays, ranging from conventional round dials (typical of most GA aircraft) to glass cockpit style PFD's. The variations of the PFD included an assortment of texturing and Digital Elevation Model (DEM) resolution combinations. A test matrix of 10 terrain display configurations (in addition to the baseline displays) were evaluated by 27 pilots of various backgrounds and experience levels

  19. Performance Comparison Between a Head-Worn Display System and a Head-Up Display for Low Visibility Commercial Operations

    NASA Technical Reports Server (NTRS)

    Arthur, Jarvis J., III; Prinzel, Lawrence J., III; Barnes, James R.; Williams, Steven P.; Jones, Denise R.; Harrison, Stephanie J.; Bailey, Randall E.

    2014-01-01

    Research, development, test, and evaluation of flight deck interface technologies is being conducted by NASA to proactively identify, develop, and mature tools, methods, and technologies for improving overall aircraft safety of new and legacy vehicles operating in Next Generation Air Transportation System (NextGen). Under the Vehicle Systems Safety Technologies (VSST) project in the Aviation Safety Program, one specific area of research is the use of small Head-Worn Displays (HWDs) as an equivalent display to a Head-Up Display (HUD). Title 14 of the US Code of Federal Regulations (CFR) 91.175 describes a possible operational credit which can be obtained with airplane equipage of a HUD or an "equivalent" display combined with Enhanced Vision (EV). If successful, a HWD may provide the same safety and operational benefits as current HUD-equipped aircraft but for significantly more aircraft in which HUD installation is neither practical nor possible. A simulation experiment was conducted to evaluate if the HWD, coupled with a head-tracker, can provide an equivalent display to a HUD. Comparative testing was performed in the Research Flight Deck (RFD) Cockpit Motion Facility (CMF) full mission, motion-based simulator at NASA Langley. Twelve airline crews conducted approach and landing, taxi, and departure operations during low visibility operations (1000' Runway Visual Range (RVR), 300' RVR) at Memphis International Airport (Federal Aviation Administration (FAA) identifier: KMEM). The results showed that there were no statistical differences in the crews performance in terms of touchdown and takeoff. Further, there were no statistical differences between the HUD and HWD in pilots' responses to questionnaires.

  20. Head-mounted active noise control system with virtual sensing technique

    NASA Astrophysics Data System (ADS)

    Miyazaki, Nobuhiro; Kajikawa, Yoshinobu

    2015-03-01

    In this paper, we apply a virtual sensing technique to a head-mounted active noise control (ANC) system we have already proposed. The proposed ANC system can reduce narrowband noise while improving the noise reduction ability at the desired locations. A head-mounted ANC system based on an adaptive feedback structure can reduce noise with periodicity or narrowband components. However, since quiet zones are formed only at the locations of error microphones, an adequate noise reduction cannot be achieved at the locations where error microphones cannot be placed such as near the eardrums. A solution to this problem is to apply a virtual sensing technique. A virtual sensing ANC system can achieve higher noise reduction at the desired locations by measuring the system models from physical sensors to virtual sensors, which will be used in the online operation of the virtual sensing ANC algorithm. Hence, we attempt to achieve the maximum noise reduction near the eardrums by applying the virtual sensing technique to the head-mounted ANC system. However, it is impossible to place the microphone near the eardrums. Therefore, the system models from physical sensors to virtual sensors are estimated using the Head And Torso Simulator (HATS) instead of human ears. Some simulation, experimental, and subjective assessment results demonstrate that the head-mounted ANC system with virtual sensing is superior to that without virtual sensing in terms of the noise reduction ability at the desired locations.

  1. Plan for evaluation of the training potential of helmet-mounted display and computer-generated synthetic imagery

    NASA Astrophysics Data System (ADS)

    Berbaum, K. S.; Kennedy, R. S.

    1985-04-01

    This report describes a plan of empirical research to evaluate the training effectiveness of a helmet-mounted display (HMD), and of computer-generated synthetic imagery (CGSI), for low level flight, navigation, and target interaction. This HMD has been developed by the Advanced Simulation Concepts Laboratory of the Naval Training Equipment Center for use in the Navy Visual Technology Research Simulator (VTRS). Optics mounted on the pilots's helmet project a scene upon a retro-reflecting screen. Two computer-image generation (CIG) channels are incorporated which present a wide-angle, low-resolution, low-detail background and an area of interest (AOI) of high resolution and detail. Eye and head tracking are used to position the display so that the AOI is presented to the fovea. The goal of HMD is to present a scene to the pilot that is indistinguishable from the real world insofar as pilot performance is concerned. The evaluation plan describes training scenarios emphasizing low level flight and ground interaction, response parameters used in measuring pilot performance, psychological experiments comparing the training efficacy of various aspects of HMD and CGSI, post stimulation subjective measures of pilot comfort, and the logistics of the research plan itself.

  2. Superimposition, symbology, visual attention, and the head-up display

    NASA Technical Reports Server (NTRS)

    Martin-Emerson, R.; Wickens, C. D.

    1997-01-01

    In two experiments we examined a number of related factors postulated to influence head-up display (HUD) performance. We addressed the benefit of reduced scanning and the cost of increasing the number of elements in the visual field by comparing a superimposed HUD with an identical display in a head-down position in varying visibility conditions. We explored the extent to which the characteristics of HUD symbology support a division of attention by contrasting conformal symbology (which links elements of the display image to elements of the far domain) with traditional instrument landing system (ILS) symbology. Together the two experiments provide strong evidence that minimizing scanning between flight instruments and the far domain contributes substantially to the observed HUD performance advantage. Experiment 1 provides little evidence for a performance cost attributable to visual clutter. In Experiment 2 the pattern of differences in lateral tracking error between conformal and traditional ILS symbology supports the hypothesis that, to the extent that the symbology forms an object with the far domain, attention may be divided between the superimposed image and its counterpart in the far domain.

  3. Head-up display in the non-precision approach

    NASA Technical Reports Server (NTRS)

    Naish, J. M.

    1980-01-01

    The problem of head-up guidance for an aircraft making an instrument approach without glide slope information is discussed. Requirements for path control are considered for each section of the approach profile and a head-up display is developed to meet these needs. The display is an unreferenced flight director which is modified by adding a ground referenced symbol as an alternative guidance component. The director is used for holding altitude in the first segment and for descent at a controlled rate in the second segment. It is used in the third segment to maintain the minimum decision altitude while assessing the approach situation. This is done by means of occasional brief changes to the referenced symbol. In the final segment a visual approach is made with the referenced symbol used continuously for path control. The display is investigated experimentally in simulated approaches made by three pilots. The results show a fair agreement between objective and subjective estimates of the quality of landing decisions.

  4. A head-mounted operating binocular for augmented reality visualization in medicine--design and initial evaluation.

    PubMed

    Birkfellner, Wolfgang; Figl, Michael; Huber, Klaus; Watzinger, Franz; Wanschitz, Felix; Hummel, Johann; Hanel, Rudolf; Greimel, Wolfgang; Homolka, Peter; Ewers, Rolf; Bergmann, Helmar

    2002-08-01

    Computer-aided surgery (CAS), the intraoperative application of biomedical visualization techniques, appears to be one of the most promising fields of application for augmented reality (AR), the display of additional computer-generated graphics over a real-world scene. Typically a device such as a head-mounted display (HMD) is used for AR. However, considerable technical problems connected with AR have limited the intraoperative application of HMDs up to now. One of the difficulties in using HMDs is the requirement for a common optical focal plane for both the realworld scene and the computer-generated image, and acceptance of the HMD by the user in a surgical environment. In order to increase the clinical acceptance of AR, we have adapted the Varioscope (Life Optics, Vienna), a miniature, cost-effective head-mounted operating binocular, for AR. In this paper, we present the basic design of the modified HMD, and the method and results of an extensive laboratory study for photogrammetric calibration of the Varioscope's computer displays to a real-world scene. In a series of 16 calibrations with varying zoom factors and object distances, mean calibration error was found to be 1.24 +/- 0.38 pixels or 0.12 +/- 0.05 mm for a 640 x 480 display. Maximum error accounted for 3.33 +/- 1.04 pixels or 0.33 +/- 0.12 mm. The location of a position measurement probe of an optical tracking system was transformed to the display with an error of less than 1 mm in the real world in 56% of all cases. For the remaining cases, error was below 2 mm. We conclude that the accuracy achieved in our experiments is sufficient for a wide range of CAS applications.

  5. Evaluation of Anti-Glare Applications for a Tactical Helmet-Mounted Display

    DTIC Science & Technology

    2012-03-01

    simulated sunlight condition. 15. SUBJECT TERMS Helmet-Mounted Display, HMD, Glare, Anti-Reflective, Hood 16. SECURITY CLASSIFICATION OF: 17...legibility with each film and HMD hood covering under normal office lighting and under a simulated sunlight condition. In this test paradigm, participants had...impediment in the form of glare as sunlight is reflected into the user’s eye. Since operators can be expected to perform their missions at any time of

  6. Perceptual design tradeoff considerations for viewing I2 and FLIR with current helmet-mounted displays

    NASA Astrophysics Data System (ADS)

    Kalich, Melvyn E.; Harding, Thomas H.; Rash, Clarence E.

    2008-04-01

    Providing both I2 (image intensified) and FLIR (forward looking infrared) images on a helmet-mounted display (HMD) requires perceptual design tradeoffs. Primary considerations center on the number, type, and placement of sensors. Perceptual drivers for these tradeoffs are derived from monocular versus biocular/binocular displays and offset of the sensors from the design eye. These conditions can create binocular rivalry, perceptual perspective distortion or hyperstereopsis, a binocular perceptual distortion that occurs when the sensors are positioned further apart than the interpupillary distance (IPD). Each of these perceptual tradeoff considerations is discussed.

  7. Helmet-mounted display human factor engineering design issues: past, present, and future

    NASA Astrophysics Data System (ADS)

    Licina, Joseph R.; Rash, Clarence E.; Mora, John C.; Ledford, Melissa H.

    1999-07-01

    An often overlooked area of helmet-mounted display (HMD) design is that of good human factors engineering. Systems which pass bench testing with flying colors can often find less enthusiastic acceptance during fielding when good human factors engineering principles are not adhered to throughout the design process. This paper addresses lessons learned on the fielding of the AH-64 Apache Integrated Helmet and Display Sight System (IHADSS) and the Aviator's Night Vision Imaging System (ANVIS). These lessons are used to develop guidance for future HMDs in such diverse areas as: user adjustments, anthropometry, fit and comfort, manpower and personnel requirements, and equipment compatibility.

  8. Toward Head-Worn Displays for Equivalent Visual Operations

    NASA Technical Reports Server (NTRS)

    Prinzel, Lawrence (Lance) J., III; Arthur, Jarvis J. (Trey); Bailey, Randall E.; Jones, Denise R.; Williams, Steven P.; Harrison, Stephanie J.

    2015-01-01

    The Next Generation Air Transportation System represents an envisioned transformation to the U.S. air transportation system that includes an "equivalent visual operations" (EVO) concept, intended to achieve the safety and operational tempos of Visual Flight Rules (VFR) operations independent of visibility conditions. Today, Federal Aviation Administration regulations provide for the use of an Enhanced Flight Visual System (EFVS) as "operational credit" to conduct approach operations below traditional minima otherwise prohibited. An essential element of an EFVS is the Head-Up Display (HUD). NASA has conducted a substantial amount of research investigating the use of HUDs for operational landing "credit", and current efforts are underway to enable manually flown operations as low as 1000 feet Runway Visual Range (RVR). Title 14 CFR 91.175 describes the use of EFVS and the operational credit that may be obtained with airplane equipage of a HUD combined with Enhanced Vision (EV) while also offering the potential use of an “equivalent” display in lieu of the HUD. A Head-Worn Display (HWD) is postulated to provide the same, or better, safety and operational benefits as current HUD-equipped aircraft but for potentially more aircraft and for lower cost. A high-fidelity simulation was conducted that examined the efficacy of HWDs as "equivalent" displays. Twelve airline flight crews conducted 1000 feet RVR approach and 300 feet RVR departure operations using either a HUD or HWD, both with simulated Forward Looking Infra-Red cameras. The paper shall describe (a) quantitative and qualitative results, (b) a comparative evaluation of these findings with prior NASA HUD studies, and (c) describe current research efforts for EFVS to provide for a comprehensive EVO capability.

  9. Head-Mounted Eye Tracking: A New Method to Describe Infant Looking

    ERIC Educational Resources Information Center

    Franchak, John M.; Kretch, Kari S.; Soska, Kasey C.; Adolph, Karen E.

    2011-01-01

    Despite hundreds of studies describing infants' visual exploration of experimental stimuli, researchers know little about where infants look during everyday interactions. The current study describes the first method for studying visual behavior during natural interactions in mobile infants. Six 14-month-old infants wore a head-mounted eye-tracker…

  10. A novel active heads-up display for driver assistance.

    PubMed

    Doshi, Anup; Cheng, Shinko Yuanhsien; Trivedi, Mohan Manubhai

    2009-02-01

    In this paper, we introduce a novel laser-based wide-area heads-up windshield display which is capable of actively interfacing with a human as part of a driver assistance system. The dynamic active display (DAD) is a unique prototype interface that presents safety-critical visual icons to the driver in a manner that minimizes the deviation of his or her gaze direction without adding to unnecessary visual clutter. As part of an automotive safety system, the DAD presents alerts in the field of view of the driver only if necessary, which is based upon the state and pose of the driver, vehicle, and environment. This paper examines the effectiveness of DAD through a comprehensive comparative experimental evaluation of a speed compliance driver assistance system, which is implemented on a vehicular test bed. Three different types of display protocols for assisting a driver to comply with speed limits are tested on actual roadways, and these are compared with a conventional dashboard display. Given the inclination, drivers who are given an overspeed warning alert reduced the time required to slow down to the speed limit by 38% (p < 0.01) as compared with the drivers not given the alert. Additionally, certain alerts decreased distraction levels by reducing the time spent looking away from the road by 63% (p < 0.01). Ultimately, these alerts demonstrate the utility and promise of the DAD system.

  11. Helmet mounted display supporting helicopter missions during en route flight and landing

    NASA Astrophysics Data System (ADS)

    Lueken, Thomas; Doehler, Hans-Ullrich; Schmerwitz, Sven

    2016-05-01

    Degraded visual environment is still a major problem for helicopter pilots especially during approach and landing. Particularly with regard to the landing phase, pilot's eyes must be directed outward in order to find visual cues as indicators for drift estimation. If lateral speed exceeds the limits it can damage the airframe or in extreme cases lead to a rollover. Since poor visibility can contribute to a loss of situation awareness and spatial disorientation, it is crucial to intuitively provide the pilot with the essential visual information he needs for a safe landing. With continuous technology advancement helmet-mounted displays (HMD) will soon become a spreading technology, because look through capability is an enabler to offer monitoring the outside view while presenting flight phase depending symbologies on the helmet display. Besides presenting primary flight information, additional information for obstacle accentuation or terrain visualization can be displayed on the visor. Virtual conformal elements like 3D pathway depiction or a 3D landing zone representation can help the pilot to maintain control until touchdown even during poor visual conditions. This paper describes first investigations in terms of both en route and landing symbology presented on a helmet mounted display system in the scope of helicopter flight trials with DLR's flying helicopter simulator ACT/FHS.

  12. Pathway Design Effects on Synthetic Vision Head-Up Displays

    NASA Technical Reports Server (NTRS)

    Kramer, Lynda J.; Prinzel, Lawrence J., III; Arthur, Jarvis J., III; Bailey, Randall E.

    2004-01-01

    NASA s Synthetic Vision Systems (SVS) project is developing technologies with practical applications that will eliminate low visibility conditions as a causal factor to civil aircraft accidents while replicating the operational benefits of clear day flight operations, regardless of the actual outside visibility condition. A major thrust of the SVS project involves the development/demonstration of affordable, certifiable display configurations that provide intuitive out-the-window terrain and obstacle information with advanced pathway guidance for transport aircraft. This experiment evaluated the influence of different tunnel and guidance concepts upon pilot situation awareness (SA), mental workload, and flight path tracking performance for Synthetic Vision display concepts using a Head-Up Display (HUD). Two tunnel formats (dynamic, minimal) were evaluated against a baseline condition (no tunnel) during simulated IMC approaches to Reno-Tahoe International airport. Two guidance cues (tadpole, follow-me aircraft) were also evaluated to assess their influence on the tunnel formats. Results indicated that the presence of a tunnel on an SVS HUD had no effect on flight path performance but that it did have significant effects on pilot SA and mental workload. The dynamic tunnel concept with the follow-me aircraft guidance symbol produced the lowest workload and provided the highest SA among the tunnel concepts evaluated.

  13. Potential see-through performance deficits in U.S. Army developmental helmet-mounted displays

    NASA Astrophysics Data System (ADS)

    Harding, Thomas H.; Rash, Clarence E.

    2004-09-01

    The U.S. Army has several helmet-mounted displays (HMDs) under development, all with unique characteristics and designs. For example, the now cancelled RAH-66 Comanche HIDSS (Helmet Integrated Display Sighting System) uses miniature liquid crystal displays as sources, and Microvision, Inc., of Bothel, Washington, is developing several prototype HMDs for the Army that incorporate a scanning laser or lasers as their source. Gone are new HMD designs that use cathode ray tubes (CRTs) as sources. A potential problem for see-through displays lies in the fact that the MTF (modulation transfer function) of flat panel displays is characterized by a good high-spatial frequency response. Although this seems counterintuitive, this high frequency response may impact the see-through detection and identification of high-spatial frequency targets because of visual masking and/or spatial frequency adaptation. A similar problem exists with the HMDs being developed by Microvision, Inc., where a high-spatial frequency noise pattern is present due to the inclusion of a diffractive exit pupil expander. Simple blurring of the HMD imagery would reduce this potential problem. In an earlier investigation, we found that a little blurring of flat panel displays does not affect small letter acuity even near threshold. Thus, it is possible to reduce the potential for see-through deficits while still maintaining maximum HMD fidelity.

  14. Magnitude of visual accommodation to a head-up display

    NASA Technical Reports Server (NTRS)

    Leitner, E. F.; Haines, R. F.

    1981-01-01

    The virtual image symbology of head-up displays (HUDs) is presented at optical infinity to the pilot. This design feature is intended to help pilots maintain visual focus distance at optical infinity. However, the accommodation response could be nearer than optical infinity, due to an individual's dark focus response. Accommodation responses were measured of two age groups of airline pilots to: (1) static symbology on a HUD; (2) a landing site background at optical infinity; (3) the combination of the HUD symbology and the landing site background; and (4) complete darkness. Results indicate that magnitude of accommodation to HUD symbology, with and without the background, is not significantly different from an infinity focus response for either age group. The dark focus response is significantly closer than optical infinity for the younger pilots, but not the older pilots, a finding consistent with previous research.

  15. Terrain Portrayal for Head-Down Displays Flight Test

    NASA Technical Reports Server (NTRS)

    Hughes, Monica F.; Glaab, Louis J.

    2003-01-01

    The Synthetic Vision Systems General Aviation (SVS-GA) element of NASA's Aviation Safety Program is developing technology to eliminate low visibility induced General Aviation (GA) accidents through the application of synthetic vision techniques. SVS displays present computer generated 3-dimensional imagery of the surrounding terrain to greatly enhance pilot's situation awareness (SA), reducing or eliminating Controlled Flight into Terrain (CFIT), as well as Low-Visibility Loss of Control (LVLOC) accidents. In addition to substantial safety benefits, SVS displays have many potential operational benefits that can lead to flight in instrument meteorological conditions (IMC) resembling those conducted in visual meteorological conditions (VMC). Potential benefits could include lower landing minimums, more approach options, reduced training time, etc. SVS conducted research will develop display concepts providing the pilot with an unobstructed view of the outside terrain, regardless of weather conditions and time of day. A critical component of SVS displays is the appropriate presentation of terrain to the pilot. The relationship between the realism of the terrain presentation and resulting enhancements of pilot SA and pilot performance has been largely undefined. Comprised of coordinated simulation and flight test efforts, the terrain portrayal for head-down displays (TP-HDD) test series examined the effects of two primary elements of terrain portrayal: variations of digital elevation model (DEM) resolution and terrain texturing. Variations in DEM resolution ranged from sparsely spaced (30 arc-sec/2,953ft) to very closely spaced data (1 arc-sec/98 ft). Variations in texture involved three primary methods: constant color, elevation-based generic, and photo-realistic, along with a secondary depth cue enhancer in the form of a fishnet grid overlay. The TP-HDD test series was designed to provide comprehensive data to enable design trades to optimize all SVS applications, as

  16. Reduce volume of head-up display by image stitching

    NASA Astrophysics Data System (ADS)

    Chiu, Yi-Feng; Su, Guo-Dung J.

    2016-09-01

    Head-up Display (HUD) is a safety feature for automobile drivers. Although there have been some HUD systems in commercial product already, their images are too small to show assistance information. Another problem, the volume of HUD is too large. We proposed a HUD including micro-projectors, rear-projection screen, microlens array (MLA) and the light source is 28 mm x 14 mm realized a 200 mm x 100 mm image in 3 meters from drivers. We want to use the MLA to reduce the volume by virtual image stitching. We design the HUD's package dimensions is 12 cm x 12 cm x 9 cm. It is able to show speed, map-navigation and night vision information. We used Liquid Crystal Display (LCD) as our image source due to its brighter image output required and the minimum volume occupancy. The MLA is a multi aperture system. The proposed MLA consists of many optical channels each transmitting a segment of the whole field of view. The design of the system provides the stitching of the partial images, so that we can see the whole virtual image.

  17. Head-up transition behavior of pilots with and without head-up display in simulated low-visibility approaches

    NASA Technical Reports Server (NTRS)

    Haines, R. F.; Fischer, E.; Price, T. A.

    1980-01-01

    To quantify head-up transition behavior with and without a flightpath type head-up display, eight rated B-727 pilots each flew 31 manual and coupled approaches in a simulator with B-727 dynamics and collimated model board external scene. Data were also obtained on the roll played by the head-up display in the coupled-to-manual transition. Various wind shears, low visibilities, and ceilings were tested along with unexpected misalignment between the runway and head-up display symbology. The symbolic format used was a conformal scene. Every pilot except one stayed head-up, flying with the display after descending below the ceiling. Without the display and as altitude decreased, the number of lookups from the instrument panel decreased and the duration of each one increased. No large differences in mean number or duration of transitions up or down were found during the head-up display runs comparing the no-misalignment with the lateral instrument landing system offset misalignment runs. The head-up display led to fewer transitions after the pilot made a decision to land or execute a missed approach. Without the display, pilots generally waited until they had descended below the ceiling to look outside the first time, but with it several pilots looked down at their panel at relatively high altitudes (if they looked down at all). Manual takeover of control was rapid and smooth both with and without the display which permitted smoother engine power changes.

  18. Design of refractive/diffractive objective for head-mounted night vision goggle

    NASA Astrophysics Data System (ADS)

    Zhao, Qiu-Ling; Wang, Zhao-Qi; Fu, Ru-Lian; Sun, Qiang; Lu, Zhen-Wu

    A refractive/diffractive objective for head-mounted night vision goggle was designed. This objective consists of six elements, including one binary surface and two hyperboloids. It has a 40[degree sign] field of view, a 1.25 f-number, and a 18 mm image diameter, with a compact structure and a light weight. All optical specifications reach proposed designing targets. Besides, we considered fabrication issues about special surfaces of the system.

  19. Study for verification testing of the helmet-mounted display in the Japanese Experimental Module.

    PubMed

    Nakajima, I; Yamamoto, I; Kato, H; Inokuchi, S; Nemoto, M

    2000-02-01

    Our purpose is to propose a research and development project in the field of telemedicine. The proposed Multimedia Telemedicine Experiment for Extra-Vehicular Activity will entail experiments designed to support astronaut health management during Extra-Vehicular Activity (EVA). Experiments will have relevant applications to the Japanese Experimental Module (JEM) operated by National Space Development Agency of Japan (NASDA) for the International Space Station (ISS). In essence, this is a proposal for verification testing of the Helmet-Mounted Display (HMD), which enables astronauts to verify their own blood pressures and electrocardiograms, and to view a display of instructions from the ground station and listings of work procedures. Specifically, HMD is a device designed to project images and data inside the astronaut's helmet. We consider this R&D proposal to be one of the most suitable projects under consideration in response to NASDA's open invitation calling for medical experiments to be conducted on JEM.

  20. A Head-Mounted Spectacle Frame for the Study of Mouse Lens-Induced Myopia

    PubMed Central

    Gu, Yangshun; Xu, Baisheng; Feng, Chunfei; Ni, Yang; Wu, Qin; Du, Chixin; Hong, Nan; Li, Peng; Ding, Zhihua; Jiang, Bo

    2016-01-01

    The mouse model has been widely employed to explore the mysteries of myopia. For now, existing techniques for induction of experimental myopia in mice can be classified into three types: (1) devices directly glued to the fur; (2) devices attached using a combination of glue and sutures; (3) devices attached using a skull-mounted apparatus. These techniques each have its advantages, disadvantages when considering the devices stability, safety, complexity, effectiveness, and so forth. Thus, techniques for myopia induction in mice have yet to be further refined to popularize the applications. In this pilot study, we introduce a new head fixation device named the head-mounted spectacle frame apparatus for the study of mouse lens-induced myopia. Surgical procedures for device attachment were relatively simple and easy to learn in our study. Effective myopia induction was validated by retinoscopy refraction and axial length measurement using optical coherence tomography. In addition, it showed improved compliance and reliable safety when compared to the published methods. The head-mounted spectacle frame apparatus provides a new choice for the study of lens-induced myopia in mouse. It also allows for the use of form deprivation, making it attractive for future experimental mouse myopia trials. PMID:26904275

  1. A miniature shoe-mounted orientation determination system for accurate indoor heading and trajectory tracking.

    PubMed

    Zhang, Shengzhi; Yu, Shuai; Liu, Chaojun; Liu, Sheng

    2016-06-01

    Tracking the position of pedestrian is urgently demanded when the most commonly used GPS (Global Position System) is unavailable. Benefited from the small size, low-power consumption, and relatively high reliability, micro-electro-mechanical system sensors are well suited for GPS-denied indoor pedestrian heading estimation. In this paper, a real-time miniature orientation determination system (MODS) was developed for indoor heading and trajectory tracking based on a novel dual-linear Kalman filter. The proposed filter precludes the impact of geomagnetic distortions on pitch and roll that the heading is subjected to. A robust calibration approach was designed to improve the accuracy of sensors measurements based on a unified sensor model. Online tests were performed on the MODS with an improved turntable. The results demonstrate that the average RMSE (root-mean-square error) of heading estimation is less than 1°. Indoor heading experiments were carried out with the MODS mounted on the shoe of pedestrian. Besides, we integrated the existing MODS into an indoor pedestrian dead reckoning application as an example of its utility in realistic actions. A human attitude-based walking model was developed to calculate the walking distance. Test results indicate that mean percentage error of indoor trajectory tracking achieves 2% of the total walking distance. This paper provides a feasible alternative for accurate indoor heading and trajectory tracking.

  2. A miniature shoe-mounted orientation determination system for accurate indoor heading and trajectory tracking

    NASA Astrophysics Data System (ADS)

    Zhang, Shengzhi; Yu, Shuai; Liu, Chaojun; Liu, Sheng

    2016-06-01

    Tracking the position of pedestrian is urgently demanded when the most commonly used GPS (Global Position System) is unavailable. Benefited from the small size, low-power consumption, and relatively high reliability, micro-electro-mechanical system sensors are well suited for GPS-denied indoor pedestrian heading estimation. In this paper, a real-time miniature orientation determination system (MODS) was developed for indoor heading and trajectory tracking based on a novel dual-linear Kalman filter. The proposed filter precludes the impact of geomagnetic distortions on pitch and roll that the heading is subjected to. A robust calibration approach was designed to improve the accuracy of sensors measurements based on a unified sensor model. Online tests were performed on the MODS with an improved turntable. The results demonstrate that the average RMSE (root-mean-square error) of heading estimation is less than 1°. Indoor heading experiments were carried out with the MODS mounted on the shoe of pedestrian. Besides, we integrated the existing MODS into an indoor pedestrian dead reckoning application as an example of its utility in realistic actions. A human attitude-based walking model was developed to calculate the walking distance. Test results indicate that mean percentage error of indoor trajectory tracking achieves 2% of the total walking distance. This paper provides a feasible alternative for accurate indoor heading and trajectory tracking.

  3. Toward Head-Up and Head-Worn Displays for Equivalent Visual Operations

    NASA Technical Reports Server (NTRS)

    Prinzel, Lawrence J., III; Arthur, Jarvis J.; Bailey, Randall E.; Shelton, Kevin J.; Kramer, Lynda J.; Jones, Denise R.; Williams, Steven P.; Harrison, Stephanie J.; Ellis, Kyle K.

    2015-01-01

    A key capability envisioned for the future air transportation system is the concept of equivalent visual operations (EVO). EVO is the capability to achieve the safety of current-day Visual Flight Rules (VFR) operations and maintain the operational tempos of VFR irrespective of the weather and visibility conditions. Enhanced Flight Vision Systems (EFVS) offer a path to achieve EVO. NASA has successfully tested EFVS for commercial flight operations that has helped establish the technical merits of EFVS, without reliance on natural vision, to runways without category II/III ground-based navigation and lighting requirements. The research has tested EFVS for operations with both Head-Up Displays (HUDs) and "HUD equivalent" Head-Worn Displays (HWDs). The paper describes the EVO concept and representative NASA EFVS research that demonstrate the potential of these technologies to safely conduct operations in visibilities as low as 1000 feet Runway Visual Range (RVR). Future directions are described including efforts to enable low-visibility approach, landing, and roll-outs using EFVS under conditions as low as 300 feet RVR.

  4. Helmet-mounted display targeting symbology color coding: an air-to-air scenario evaluation

    NASA Astrophysics Data System (ADS)

    Geiselman, Eric E.; Post, David L.

    1999-07-01

    Laboratory and flight test evaluations have consistently demonstrated the potential for helmet-mounted display (HMD) presented information to enhance air combat performance. The Air Force Research Laboratory's (AFRL's) Helmet-Mounted Sight Plus (HMS+) program seeks to provide further enhancement by enabling the presentation of multi-color symbology and sensor imagery. To take proper advantage of color-capable HMDs, systematic evaluations must be conducted to identify the best color-coding techniques. The experiment described here is the second we have conducted to address this need. The first experiment identified the better of two competing color coding strategies for air-to-air weapons symbology and indicated that pilots preferred the color codes over an otherwise equivalent monochrome baseline. The present experiment compared the 'winning' color code to the monochrome baseline during trials of a complex multi-player air-to-air weapon delivery scenario. Twelve fighter pilots representing three different countries (U.S., U.K., and Sweden) flew simulator trials that included target identification, intercept, attack, missile launch, and defensive maneuvering tasks. Participants' subjective feedback and performance data indicated a preference for color coded symbology.

  5. Rotorcraft aircrew systems concepts airborne laboratory (RASCAL) helmet-mounted display flight research

    NASA Astrophysics Data System (ADS)

    Hindson, William S.; Njaka, Chima E.; Aiken, Edwin W.; Barnhart, Warren A.

    1994-06-01

    The Rotorcraft Aircrew Systems Concepts Airborne Laboratory (RASCAL) is a UH-60A Black Hawk helicopter that is being modified by the US Army and NASA for flight systems research. One of the objectives of the research is to develop and integrate technologies for Automated Nap-of-the Earth (ANOE) flight. The principal elements of this system include video imaging sensors, advanced real-time image processing capabilities, a graphics supercomputer, a wide field-of-view color helmet mounted display (HMD), and an advanced fly-by-wire flight control system. The development methodology and the current status of the ANOE Flight Program are summarized, a description of the visionics system is provided, and the plans for the initial applications of the color HMD are presented.

  6. Helmet-mounted displays on the next battlefield: a perspective on HMD reliability and mantainability

    NASA Astrophysics Data System (ADS)

    Verruso, Janis

    1999-07-01

    The United States Army introduced Helmet Mounted Displays (HMD) into its weapon inventory over fifteen years ago with the fielding of the AH-64 Attack Helicopter. To date the Integrated Helmet and Display Sight System (IHADSS) is still the only fielded HMD in the Army inventory. The HMD contractor community can expect the Army to increase the utility of HMDs in the next decade on a variety of weapon platforms. This is evident through such development programs as Land Warrior and Comanche, and advanced developments such as Air Warrior, Mounted Warrior, and the Driver Vehicle Enhancement Program. Should these programs continue to mature into production, we can expect to see HMD technology proliferate on several more solider, vehicle and aircraft platforms. The U.S. Army is setting in motion a massive force restructuring under Force XXI and Army After Next doctrines. These force structures of the future call out for significantly increased reliability requirements in new technology material acquisition, and methods for how these technologies are sustained on the battlefield. HMD contractors, along with the rest of the defense industry, will be directly impacted by these revolutionary requirements. The changes forthcoming bring challenges and new opportunities both in the laboratory and through the logistical support contractors are expected provide. This paper identifies some of the challenges HMD contractors will face as the Army moves forward to integrate HMDs on a multitude of legacy and newly developed weapon platforms. It sets the stage with a summary of events that occurred in 1990 when Honeywell was tasked by the Army to support IHADSS repair during Operation Desert Shield and Desert Storm. It then examines some of the future changes we as contractors can expect from the Army in future material development and product support.

  7. SVGA and XGA active matrix microdisplays for head-mounted applications

    NASA Astrophysics Data System (ADS)

    Alvelda, Phillip; Bolotski, Michael; Brown, Imani L.

    2000-03-01

    The MicroDisplay Corporation's liquid crystal on silicon (LCOS) display devices are based on the union of several technologies with the extreme integration capability of conventionally fabricated CMOS substrates. The fast liquid crystal operation modes and new scalable high-performance pixel addressing architectures presented in this paper enable substantially improved color, contrast, and brightness while still satisfying the optical, packaging, and power requirements of portable applications. The entire suite of MicroDisplay's technologies was devised to create a line of mixed-signal application-specific integrated circuits (ASICs) in single-chip display systems. Mixed-signal circuits can integrate computing, memory, and communication circuitry on the same substrate as the display drivers and pixel array for a multifunctional complete system-on-a-chip. System-on-a-chip benefits also include reduced head supported weight requirements through the elimination of off-chip drive electronics.

  8. Evaluation of anti-glare applications for a tactical helmet-mounted display

    NASA Astrophysics Data System (ADS)

    Roll, Jason L.; Trew, Noel J. M.; Geis, Matthew R.; Havig, Paul R.

    2011-06-01

    Non see-through, monocular helmet mounted displays (HMDs) provide warfighters with unprecedented amounts of information at a glance. The US Air Force recognizes their usefulness, and has included such an HMD as part of a kit for ground-based, Battlefield Airmen. Despite their many advantages, non see-through HMDs occlude a large portion of the visual field when worn as designed, directly in front of the eye. To address this limitation, operators have chosen to wear it just above the cheek, angled up toward the eye. However, wearing the HMD in this position exposes the display to glare, causing a potential viewing problem. In order to address this problem, we tested several film and HMD hood applications for their effect on glare. The first experiment objectively examined the amount of light reflected off the display with each application in a controlled environment. The second experiment used human participants to subjectively evaluate display readability/legibility with each film and HMD hood covering under normal office lighting and under a simulated sunlight condition. In this test paradigm, participants had to correctly identify different icons on a map and different words on a white background. Our results indicate that though some applications do reduce glare, they do not significantly improve the HMD's readability/legibility compared with an uncovered screen. This suggests that these post-production modifications will not completely solve this problem and underscores the importance of employing a user-centered approach early in the design cycle to determine an operator's use-case before manufacturing an HMD for a particular user community.

  9. Head-mounted LED for optogenetic experiments of freely-behaving animal

    NASA Astrophysics Data System (ADS)

    Kwon, Ki Yong; Gnade, Andrew G.; Rush, Alexander D.; Patten, Craig D.

    2016-03-01

    Recent developments in optogenetics have demonstrated the ability to target specific types of neurons with sub-millisecond temporal precision via direct optical stimulation of genetically modified neurons in the brain. In most applications, the beam of a laser is coupled to an optical fiber, which guides and delivers the optical power to the region of interest. Light emitting diodes (LEDs) are an alternative light source for optogenetics and they provide many advantages over a laser based system including cost, size, illumination stability, and fast modulation. Their compact size and low power consumption make LEDs suitable light sources for a wireless optogenetic stimulation system. However, the coupling efficiency of an LED's output light into an optical fiber is lower than a laser due to its noncollimated output light. In typical chronic optogenetic experiment, the output of the light source is transmitted to the brain through a patch cable and a fiber stub implant, and this configuration requires two fiber-to-fiber couplings. Attenuation within the patch cable is potential source of optical power loss. In this study, we report and characterize a recently developed light delivery method for freely-behaving animal experiments. We have developed a head-mounted light source that maximizes the coupling efficiency of an LED light source by eliminating the need for a fiber optic cable. This miniaturized LED is designed to couple directly to the fiber stub implant. Depending on the desired optical power output, the head-mounted LED can be controlled by either a tethered (high power) or battery-powered wireless (moderate power) controller. In the tethered system, the LED is controlled through 40 gauge micro coaxial cable which is thinner, more flexible, and more durable than a fiber optic cable. The battery-powered wireless system uses either infrared or radio frequency transmission to achieve real-time control. Optical, electrical, mechanical, and thermal

  10. Visually Guided Navigation: Head-Mounted Eye-Tracking of Natural Locomotion in Children and Adults

    PubMed Central

    Franchak, John M.; Adolph, Karen E.

    2010-01-01

    The current study showed that visual fixation of obstacles is not required for rapid and adaptive navigation of obstacles. Children and adults wore a wireless, head-mounted eye-tracker during a visual search task in a room cluttered with obstacles. They spontaneously walked, jumped, and ran through the room, stepping up, down, and over obstacles. Both children and adults navigated adaptively without fixating obstacles, however, adults fixated less often than children. We discuss several possibilities for why obstacle navigation may shift from foveal to peripheral control over development. PMID:20932993

  11. Visually guided navigation: head-mounted eye-tracking of natural locomotion in children and adults.

    PubMed

    Franchak, John M; Adolph, Karen E

    2010-12-01

    The current study showed that visual fixation of obstacles is not required for rapid and adaptive navigation of obstacles. Children and adults wore a wireless, head-mounted eye-tracker during a visual search task in a room cluttered with obstacles. They spontaneously walked, jumped, and ran through the room, stepping up, down, and over obstacles. Both children and adults navigated adaptively without fixating obstacles, however, adults fixated less often than children. We discuss several possibilities for why obstacle navigation may shift from foveal to peripheral control over development.

  12. Common software and interface for different helmet-mounted display (HMD) aircraft symbology sets

    NASA Astrophysics Data System (ADS)

    Mulholland, Fred F.

    2000-06-01

    Different aircraft in different services and countries have their own set of symbology they want displayed on their HMD. Even as flight symbolgy is standardized, there will still be some differences for types of aircraft, different weapons, different sensors, and different countries. As an HMD supplier, we want to provide a system that can be used across all these applications with no changes in the system, including no changes in the software. This HMD system must also provide the flexibility to accommodate new symbology as it is developed over the years, again, with no change in the HMD software. VSI has developed their HMD software to accommodate F-15, F- 16, F-18, and F-22 symbology sets for the Joint Helmet Mounted Cueing System. It also has the flexibility to accommodate the aircraft types and services of the Joint Strike Fighter: Conventional Takeoff and Landing variant for the USAF, Carrier-based Variant for the USN, and the Short Takeoff and Vertical Landing variant for the USMC and U.K. Royal Navy and Air Force. The key to this flexibility is the interface definition. The interface parameters are established at power-on with the download of an interface definition data set. This data set is used to interpret symbology commands from the aircraft OFP during operation and provide graphic commands to the HMD software. This presentation will define the graphics commands, provide an example of how the interface definition data set is defined, and then show how symbology commands produce a display.

  13. A Decision Analysis Framework for Evaluation of Helmet Mounted Display Alternatives for Fighter Aircraft

    DTIC Science & Technology

    2014-12-26

    platform. Based on the senior decision maker preferences and available system data, Alternative 1 - Scorpion Helmet Mounted Cueing System, scored 0.481... Scorpion Helmet Mounted Cueing System ............................................................ 89 viii Joint Helmet Mounted Cueing System (JHMCS...Alternative 1- Scorpion (Thales Visionix Technical Overview).................... 89 Figure 33 : Alternative 2 - JHMCS

  14. Reading from a Head-Fixed Display during Walking: Adverse Effects of Gaze Stabilization Mechanisms

    PubMed Central

    Borg, Olivier; Casanova, Remy; Bootsma, Reinoud J.

    2015-01-01

    Reading performance during standing and walking was assessed for information presented on earth-fixed and head-fixed displays by determining the minimal duration during which a numerical time stimulus needed to be presented for 50% correct naming answers. Reading from the earth-fixed display was comparable during standing and walking, with optimal performance being attained for visual character sizes in the range of 0.2° to 1°. Reading from the head-fixed display was impaired for small (0.2-0.3°) and large (5°) visual character sizes, especially during walking. Analysis of head and eye movements demonstrated that retinal slip was larger during walking than during standing, but remained within the functional acuity range when reading from the earth-fixed display. The detrimental effects on performance of reading from the head-fixed display during walking could be attributed to loss of acuity resulting from large retinal slip. Because walking activated the angular vestibulo-ocular reflex, the resulting compensatory eye movements acted to stabilize gaze on the information presented on the earth-fixed display but destabilized gaze from the information presented on the head-fixed display. We conclude that the gaze stabilization mechanisms that normally allow visual performance to be maintained during physical activity adversely affect reading performance when the information is presented on a display attached to the head. PMID:26053622

  15. Reading from a Head-Fixed Display during Walking: Adverse Effects of Gaze Stabilization Mechanisms.

    PubMed

    Borg, Olivier; Casanova, Remy; Bootsma, Reinoud J

    2015-01-01

    Reading performance during standing and walking was assessed for information presented on earth-fixed and head-fixed displays by determining the minimal duration during which a numerical time stimulus needed to be presented for 50% correct naming answers. Reading from the earth-fixed display was comparable during standing and walking, with optimal performance being attained for visual character sizes in the range of 0.2° to 1°. Reading from the head-fixed display was impaired for small (0.2-0.3°) and large (5°) visual character sizes, especially during walking. Analysis of head and eye movements demonstrated that retinal slip was larger during walking than during standing, but remained within the functional acuity range when reading from the earth-fixed display. The detrimental effects on performance of reading from the head-fixed display during walking could be attributed to loss of acuity resulting from large retinal slip. Because walking activated the angular vestibulo-ocular reflex, the resulting compensatory eye movements acted to stabilize gaze on the information presented on the earth-fixed display but destabilized gaze from the information presented on the head-fixed display. We conclude that the gaze stabilization mechanisms that normally allow visual performance to be maintained during physical activity adversely affect reading performance when the information is presented on a display attached to the head.

  16. Measurement and reduction of system latency in see-through helmet mounted display (HMD) systems

    NASA Astrophysics Data System (ADS)

    Vincenzi, Dennis A.; Deaton, John E.; Blickenderfer, Elizabeth L.; Pray, Rick; Williams, Barry; Buker, Timothy J.

    2010-04-01

    Future military aviation platforms such as the proposed Joint Strike Fighter F-35 will integrate helmet mounted displays (HMDs) with the avionics and weapon systems to the degree that the HMDs will become the aircraft's primary display system. In turn, training of pilot flight skills using HMDs will be essential in future training systems. In order to train these skills using simulation based training, improvements must be made in the integration of HMDs with out-thewindow (OTW) simulations. Currently, problems such as latency contribute to the onset of simulator sickness and provide distractions during training with HMD simulator systems that degrade the training experience. Previous research has used Kalman predictive filters as a means of mitigating the system latency present in these systems. While this approach has yielded some success, more work is needed to develop innovative and improved strategies that reduce system latency as well as to include data collected from the user perspective as a measured variable during test and evaluation of latency reduction strategies. The purpose of this paper is twofold. First, the paper describes a new method to measure and assess system latency from the user perspective. Second, the paper describes use of the testbed to examine the efficacy of an innovative strategy that combines a customized Kalman filter with a neural network approach to mitigate system latency. Results indicate that the combined approach reduced system latency significantly when compared to baseline data and the traditional Kalman filter. Reduced latency errors should mitigate the onset of simulator sickness and ease simulator sickness symptomology. Implications for training systems will be discussed.

  17. X-31 helmet-mounted visual and audio display (HMVAD) system

    NASA Astrophysics Data System (ADS)

    Boehmer, Steven C.

    1994-06-01

    Agile aircraft (X-29, X-31, F-18 High Alpha Research Vehicle and F-16 Multi-Axis Thrust Vector) test pilots, while flying at high angles of attack, experience difficulty predicting their flight path trajectory. To compensate for the loss of this critical element of situational awareness, the X-31 International Test Organization (ITO) installed and evaluated a helmet mounted display (HMD) system into an X-31 aircraft and simulator. Also investigated for incorporation within the HMD system and flight evaluation was another candidate technology for improving situational awareness -three dimensional audio. This was the first flight test evaluating the coupling of visual and audio cueing for aircrew aiding. The focus of the endeavor, which implemented two visual and audio formats, was to examine the extent visual and audio orientation cueing enhanced situational awareness and improved pilot performance during tactical flying. This paper provides an overview of the X-31 HMVAD system, describes the visual and audio symbology, presents a summary of the pilots' subjective evaluation of the system following its use in simulation and flight test, and outlines the future plans for the X-31 HMVAD system.

  18. Low-cost day/night helmet-mounted displays (HMD) in airborne operations

    NASA Astrophysics Data System (ADS)

    Casey, Curtis J.

    1999-07-01

    Current doctrine dictates a requirement for conducting 24-hour operations on the modern battlefield either in a rural or urban environment. To date, Night Vision Goggles (NVGs) along with Infrared sensors provide the bulk of vision aids that allow crew members to engage in tactical operations at night and during periods of low and reduced visibility. Since operations employing these devices, as well as operational doctrine, require the crewmember to fly 'heads-out,' Heads-Up Displays (HUDs), enumerating flight parameters, engine and navigation information have come into existence, greatly reducing the workload on today's combat aviators. A fine example is the Marconi/Tracor ANVS-7. This device employs a symbol generator and CRT to project symbology of critical aircraft parameters into the Night Vision Goggle giving the aviator a HUD capability while engaged in NVG night operations. The system is limited to aided vision night operations employing NVGs. The same criteria that create a need for supplying critical flight information at night exist for day and night unaided vision operations. However, there is no system in production to answer this obvious need. There are several reasons for this: (1) Available technology that will offer a low-cost solution for days ops, (2) Ergonomic and Human factors Issues, (3) Competition with currently fielded systems (ANVS-7), (4) Cost. Highly sophisticated HMDs such as the Apache IHADSS and the Comanche HIDSS, which combine navigation, targeting as well as weapons and flight status for 24 hour, all-weather operations are far too expensive and, in many cases, inappropriate for the majority of Combat Support aircraft. Using internal R&D Kaiser Electronics has developed a low-cost HMD -- called Lite EyeTM HMD -- that is capable of being used in day and night operations that addresses the aforementioned issues. The solution, using recent advances in solid state display technology, maximizes the use of currently fielded equipment

  19. Head-mounted eye tracking: a new method to describe infant looking.

    PubMed

    Franchak, John M; Kretch, Kari S; Soska, Kasey C; Adolph, Karen E

    2011-01-01

    Despite hundreds of studies describing infants' visual exploration of experimental stimuli, researchers know little about where infants look during everyday interactions. The current study describes the first method for studying visual behavior during natural interactions in mobile infants. Six 14-month-old infants wore a head-mounted eye-tracker that recorded gaze during free play with mothers. Results revealed that infants' visual exploration is opportunistic and depends on the availability of information and the constraints of infants' own bodies. Looks to mothers' faces were rare following infant-directed utterances but more likely if mothers were sitting at infants' eye level. Gaze toward the destination of infants' hand movements was common during manual actions and crawling, but looks toward obstacles during leg movements were less frequent.

  20. Autonomous Head-mounted Electrophysiology Systems for Freely-Behaving Primates

    PubMed Central

    Nuyujukian, Paul; Foster, Justin; Shenoy, Krishna V.

    2011-01-01

    Recent technological advances have led to new lightweight battery-operated systems for electrophysiology. Such systems are head mounted, run for days without experimenter intervention, and can record and stimulate from single or multiple electrodes implanted in a freely-behaving primates. Here we discuss existing systems, studies that use them, and how they can augment traditional, physically restrained, “in-rig” electrophysiology. With existing technical capabilities these systems can acquire multiple signal classes, such as spikes, local field potential, and electromyography signals, and can stimulate based on real-time processing of recorded signals. Moving forward, this class of technologies, along with advances in neural signal processing and behavioral monitoring, have the potential to dramatically expand the scope and scale of electrophysiological studies. PMID:20655733

  1. Head-mounted eye-tracking: A new method to describe infant looking

    PubMed Central

    Franchak, John M.; Kretch, Kari S.; Soska, Kasey C.; Adolph, Karen E.

    2011-01-01

    Despite hundreds of studies describing infants’ visual exploration of experimental stimuli, researchers know little about where infants look during everyday interactions. The current study describes the first method for studying visual behavior during natural interactions in mobile infants. Six 14-month-old infants wore a head-mounted eye-tracker that recorded gaze during free play with mothers. Results revealed that infants’ visual exploration is opportunistic and depends on the availability of information and the constraints of infants’ own bodies. Looks to mothers’ faces were rare following infant-directed utterances, but more likely if mothers were sitting at infants’ eye level. Gaze toward the destination of infants’ hand movements was common during manual actions and crawling, but looks toward obstacles during leg movements were less frequent. PMID:22023310

  2. Color Helmet Mounted Display System with Real Time Computer Generated and Video Imagery for In-Flight Simulation

    NASA Technical Reports Server (NTRS)

    Sawyer, Kevin; Jacobsen, Robert; Aiken, Edwin W. (Technical Monitor)

    1995-01-01

    NASA Ames Research Center and the US Army are developing the Rotorcraft Aircrew Systems Concepts Airborne Laboratory (RASCAL) using a Sikorsky UH-60 helicopter for the purpose of flight systems research. A primary use of the RASCAL is in-flight simulation for which the visual scene will use computer generated imagery and synthetic vision. This research is made possible in part to a full color wide field of view Helmet Mounted Display (HMD) system that provides high performance color imagery suitable for daytime operations in a flight-rated package. This paper describes the design and performance characteristics of the HMD system. Emphasis is placed on the design specifications, testing, and integration into the aircraft of Kaiser Electronics' RASCAL HMD system that was designed and built under contract for NASA. The optical performance and design of the Helmet mounted display unit will be discussed as well as the unique capabilities provided by the system's Programmable Display Generator (PDG).

  3. A conformal head-up display for the visual approach

    NASA Technical Reports Server (NTRS)

    Naish, J. M.

    1973-01-01

    The degree of conformity used in matching a superimposed display to its visual background is considered in relation to the information available for vertical guidance and control during a purely visual approach. The information may be represented by individual symbols or combined in a single symbol, and the relative merits of these methods are discussed. A fully conformal display format is developed for the purpose of showing both the position and direction of the flight path, with provision for the effects of disturbances, ILS compatibility, and control needs. The field of view needed for all conditions and phases of the visual approach with a fully conformal display is studied in relation to the limitations of conventional collimator systems. Methods are discussed which depend on deviation of the sight line, and on windshield reflection of the uncollimated image of a simple pointer. Limited flight tests show some promise for the uncollimated method.

  4. Fiber Optic Development For Use On The Fiber Optic Helmet Mounted Display

    NASA Astrophysics Data System (ADS)

    Thomas, Melvin L.; Siegmund, Walter P.; Antos, Steven E.; Robinson, Richard M.

    1989-09-01

    The Fiber Optic Helmet Mounted Display (FOHMD) developed by CAE for the US Air Force Human Resources Laboratory (AFHRL), requires very large format, coherant fiber optic cables. These cables must support the FOHMD's demanding modulation transfer function (MTF) requirements in full color and be flexible, durable, lightweight, and up to six feet long. These requirements have so constrained glass technology that conventional approaches are not capable of delivering the requisite performance. The cables currently used on FOHMD systems have alternating layers of inactive material to buffer linear arrays of multifibers so that a lighter weight 25 by 19 mm end size is achieved with 5 micron core size individual fibers. This skip-layer, multifiber approach delivers reasonable performance when using spectral multiplexing across the inactive layers. However, residual fixed pattern noise, broken multifibers, and inadequate resolution have reduced system performance. Because of the critical influence of the fiber optic cables on overall system performance, an alternative, but riskier process, is being explored. Several smaller experimental cables have been assembled using leachable, fused, multifibers arrayed in a hexagonal pattern. The inconspicuous mating of hexagonal elements should be possible now because of an order of magnitude improvement in cable drawing technology. Fused/leached fiber optic cables have the potential to provide image transmission capability equal to ten channels of the best available computer image generators. When coupled with chromatic enhancement to mask fixed pattern and broken fiber noise, the resulting MTF of the FOHMD optics would deliver a resolution equal to 1.5 arc minutes per pixel.

  5. The impact of human factors, crashworthiness and optical performance design requirements on helmet-mounted display development from the 1970s to the present

    NASA Astrophysics Data System (ADS)

    Harding, Thomas H.; Rash, Clarence E.; McLean, William E.; Martin, John S.

    2015-05-01

    Driven by the operational needs of modern warfare, the helmet-mounted display (HMD) has matured from a revolutionary, but impractical, World War I era idea for an infantry marksman's helmet-mounted weapon delivery system to a sophisticated and ubiquitous display and targeting system that dominates current night warfighting operations. One of the most demanding applications for HMD designs has been in Army rotary-wing aviation, where HMDs offer greater direct access to visual information and increased situational awareness in an operational environment where information availability is critical on a second-to-second basis. However, over the past 40 years of extensive HMD development, a myriad of crashworthiness, optical, and human factors issues have both frustrated and challenged designers. While it may be difficult to attain a full consensus on which are the most important HMD design factors, certainly head-supported weight (HSW), exit pupil size, field-of-view, image resolution and physical eye relief have been among the most critical. A confounding factor has been the interrelationship between the many design issues, such as early attempts to use non-glass optical elements to lower HSW, but at the cost of image quality, and hence, pilot visual performance. This paper traces how the role of the demanding performance requirements placed on HMDs by the U.S. Army aviation community has impacted the progress of HMD designs towards the Holy Grail of HMD design: a wide field-of-view, high resolution, binocular, full-color, totally crashworthy system.

  6. Wearable and augmented reality displays using MEMS and SLMs

    NASA Astrophysics Data System (ADS)

    Urey, Hakan; Ulusoy, Erdem; Kazempourradi, Seyedmahdi M. K.; Mengu, Deniz; Olcer, Selim; Holmstrom, Sven T.

    2016-03-01

    In this talk, we present the various types of 3D displays, head-mounted projection displays and wearable displays developed in our group using MEMS scanners, compact RGB laser light sources, and spatial light modulators.

  7. Non-RF wireless helmet-mounted display and two-way audio connectivity using covert free-space optical communications

    NASA Astrophysics Data System (ADS)

    Strauss, M.; Volfson, L.

    2011-06-01

    Providing the warfighter with Head or Helmet Mounted Displays (HMDs) while in tracked vehicles provides a means to visually maintain access to systems information while in a high vibration environment. The high vibration and unique environment of military tracked and turreted vehicles impact the ability to distinctly see certain information on an HMD, especially small font size or graphics and information that requires long fixation (staring), rather than a brief or peripheral glance. The military and commercial use of HMDs was compiled from market research, market trends, and user feedback. Lessons learned from previous military and commercial use of HMD products were derived to determine the feasibility of HMDs use in the high vibration and the unique environments of tracked vehicles. The results are summarized into factors that determine HMD features which must be specified for successful implementation.

  8. Compensating sampling errors in stabilizing helmet-mounted displays using auxiliary acceleration measurements

    NASA Technical Reports Server (NTRS)

    Merhav, S.; Velger, M.

    1991-01-01

    A method based on complementary filtering is shown to be effective in compensating for the image stabilization error due to sampling delays of HMD position and orientation measurements. These delays would otherwise have prevented the stabilization of the image in HMDs. The method is also shown to improve the resolution of the head orientation measurement, particularly at low frequencies, thus providing smoother head control commands, which are essential for precise head pointing and teleoperation.

  9. Toward eyeglasses-based electronic displays

    NASA Astrophysics Data System (ADS)

    Spitzer, Mark B.; Aquilino, P. D.; McClelland, Robert W.; Rensing, Noa M.

    1997-06-01

    The development of a head mounted display concealed within eyeglasses has been a long term objective of many head mounted display (HMD) development efforts. This paper will review design concepts from the literature, with a view toward assessing the practical merits of the various approaches. The factors of importance in miniaturizing a HMD will be summarized. Finally, we will briefly summarize some new approaches including the use of alternative display technology that may lead to a display system hidden within eyeglasses frames.

  10. Sound localization with head movement: implications for 3-d audio displays

    PubMed Central

    McAnally, Ken I.; Martin, Russell L.

    2014-01-01

    Previous studies have shown that the accuracy of sound localization is improved if listeners are allowed to move their heads during signal presentation. This study describes the function relating localization accuracy to the extent of head movement in azimuth. Sounds that are difficult to localize were presented in the free field from sources at a wide range of azimuths and elevations. Sounds remained active until the participants' heads had rotated through windows ranging in width of 2, 4, 8, 16, 32, or 64° of azimuth. Error in determining sound-source elevation and the rate of front/back confusion were found to decrease with increases in azimuth window width. Error in determining sound-source lateral angle was not found to vary with azimuth window width. Implications for 3-d audio displays: the utility of a 3-d audio display for imparting spatial information is likely to be improved if operators are able to move their heads during signal presentation. Head movement may compensate in part for a paucity of spectral cues to sound-source location resulting from limitations in either the audio signals presented or the directional filters (i.e., head-related transfer functions) used to generate a display. However, head movements of a moderate size (i.e., through around 32° of azimuth) may be required to ensure that spatial information is conveyed with high accuracy. PMID:25161605

  11. Visuomotor adaptation in head-mounted virtual reality versus conventional training

    PubMed Central

    Anglin, J. M.; Sugiyama, T.; Liew, S.-L.

    2017-01-01

    Immersive, head-mounted virtual reality (HMD-VR) provides a unique opportunity to understand how changes in sensory environments affect motor learning. However, potential differences in mechanisms of motor learning and adaptation in HMD-VR versus a conventional training (CT) environment have not been extensively explored. Here, we investigated whether adaptation on a visuomotor rotation task in HMD-VR yields similar adaptation effects in CT and whether these effects are achieved through similar mechanisms. Specifically, recent work has shown that visuomotor adaptation may occur via both an implicit, error-based internal model and a more cognitive, explicit strategic component. We sought to measure both overall adaptation and balance between implicit and explicit mechanisms in HMD-VR versus CT. Twenty-four healthy individuals were placed in either HMD-VR or CT and trained on an identical visuomotor adaptation task that measured both implicit and explicit components. Our results showed that the overall timecourse of adaption was similar in both HMD-VR and CT. However, HMD-VR participants utilized a greater cognitive strategy than CT, while CT participants engaged in greater implicit learning. These results suggest that while both conditions produce similar results in overall adaptation, the mechanisms by which visuomotor adaption occurs in HMD-VR appear to be more reliant on cognitive strategies. PMID:28374808

  12. Visuomotor adaptation in head-mounted virtual reality versus conventional training.

    PubMed

    Anglin, J M; Sugiyama, T; Liew, S-L

    2017-04-04

    Immersive, head-mounted virtual reality (HMD-VR) provides a unique opportunity to understand how changes in sensory environments affect motor learning. However, potential differences in mechanisms of motor learning and adaptation in HMD-VR versus a conventional training (CT) environment have not been extensively explored. Here, we investigated whether adaptation on a visuomotor rotation task in HMD-VR yields similar adaptation effects in CT and whether these effects are achieved through similar mechanisms. Specifically, recent work has shown that visuomotor adaptation may occur via both an implicit, error-based internal model and a more cognitive, explicit strategic component. We sought to measure both overall adaptation and balance between implicit and explicit mechanisms in HMD-VR versus CT. Twenty-four healthy individuals were placed in either HMD-VR or CT and trained on an identical visuomotor adaptation task that measured both implicit and explicit components. Our results showed that the overall timecourse of adaption was similar in both HMD-VR and CT. However, HMD-VR participants utilized a greater cognitive strategy than CT, while CT participants engaged in greater implicit learning. These results suggest that while both conditions produce similar results in overall adaptation, the mechanisms by which visuomotor adaption occurs in HMD-VR appear to be more reliant on cognitive strategies.

  13. Head mounted DMD based projection system for natural and prosthetic visual stimulation in freely moving rats

    PubMed Central

    Arens-Arad, Tamar; Farah, Nairouz; Ben-Yaish, Shai; Zlotnik, Alex; Zalevsky, Zeev; Mandel, Yossi

    2016-01-01

    Novel technologies are constantly under development for vision restoration in blind patients. Many of these emerging technologies are based on the projection of high intensity light patterns at specific wavelengths, raising the need for the development of specialized projection systems. Here we present and characterize a novel projection system that meets the requirements for artificial retinal stimulation in rats and enables the recording of cortical responses. The system is based on a customized miniature Digital Mirror Device (DMD) for pattern projection, in both visible (525 nm) and NIR (915 nm) wavelengths, and a lens periscope for relaying the pattern directly onto the animal’s retina. Thorough system characterization and the investigation of the effect of various parameters on obtained image quality were performed using ZEMAX. Simulation results revealed that images with an MTF higher than 0.8 were obtained with little effect of the vertex distance. Increased image quality was obtained at an optimal pupil diameter and smaller field of view. Visual cortex activity data was recorded simultaneously with pattern projection, further highlighting the importance of the system for prosthetic vision studies. This novel head mounted projection system may prove to be a vital tool in studying natural and artificial vision in behaving animals. PMID:27731346

  14. Head mounted DMD based projection system for natural and prosthetic visual stimulation in freely moving rats

    NASA Astrophysics Data System (ADS)

    Arens-Arad, Tamar; Farah, Nairouz; Ben-Yaish, Shai; Zlotnik, Alex; Zalevsky, Zeev; Mandel, Yossi

    2016-10-01

    Novel technologies are constantly under development for vision restoration in blind patients. Many of these emerging technologies are based on the projection of high intensity light patterns at specific wavelengths, raising the need for the development of specialized projection systems. Here we present and characterize a novel projection system that meets the requirements for artificial retinal stimulation in rats and enables the recording of cortical responses. The system is based on a customized miniature Digital Mirror Device (DMD) for pattern projection, in both visible (525 nm) and NIR (915 nm) wavelengths, and a lens periscope for relaying the pattern directly onto the animal’s retina. Thorough system characterization and the investigation of the effect of various parameters on obtained image quality were performed using ZEMAX. Simulation results revealed that images with an MTF higher than 0.8 were obtained with little effect of the vertex distance. Increased image quality was obtained at an optimal pupil diameter and smaller field of view. Visual cortex activity data was recorded simultaneously with pattern projection, further highlighting the importance of the system for prosthetic vision studies. This novel head mounted projection system may prove to be a vital tool in studying natural and artificial vision in behaving animals.

  15. Head mounted DMD based projection system for natural and prosthetic visual stimulation in freely moving rats.

    PubMed

    Arens-Arad, Tamar; Farah, Nairouz; Ben-Yaish, Shai; Zlotnik, Alex; Zalevsky, Zeev; Mandel, Yossi

    2016-10-12

    Novel technologies are constantly under development for vision restoration in blind patients. Many of these emerging technologies are based on the projection of high intensity light patterns at specific wavelengths, raising the need for the development of specialized projection systems. Here we present and characterize a novel projection system that meets the requirements for artificial retinal stimulation in rats and enables the recording of cortical responses. The system is based on a customized miniature Digital Mirror Device (DMD) for pattern projection, in both visible (525 nm) and NIR (915 nm) wavelengths, and a lens periscope for relaying the pattern directly onto the animal's retina. Thorough system characterization and the investigation of the effect of various parameters on obtained image quality were performed using ZEMAX. Simulation results revealed that images with an MTF higher than 0.8 were obtained with little effect of the vertex distance. Increased image quality was obtained at an optimal pupil diameter and smaller field of view. Visual cortex activity data was recorded simultaneously with pattern projection, further highlighting the importance of the system for prosthetic vision studies. This novel head mounted projection system may prove to be a vital tool in studying natural and artificial vision in behaving animals.

  16. Full-color see-through daylight-readable goggle-mounted display

    NASA Astrophysics Data System (ADS)

    DeJong, Christian Dean

    2011-06-01

    See-through near-to-eye displays offer an opportunity to present visual information laid on top of the view of the real world. The information presented can be used to augment or annotate the scene the user sees. Microvision has developed a see-through, full-color, daylight-readable, monocular display in a goggle form factor. The image source for the display is a Pico Display Engine (PDE) that uses modulated red, green, and blue lasers reflecting off a MEMS based bi-axial scanning mirror to create an image. This image is relayed to the eye through a pupil-expanding substrateguiding optic. The low Lagrange invariant laser-based display engine is an excellent match for the substrate guided optics for presenting the user with an infinite conjugate image. This paper discusses design considerations and performance characteristics of the eyewear display.

  17. Helmet-Mounted Displays for Use in Air Force Training and Simulation

    DTIC Science & Technology

    2005-11-01

    update of imagery relative to the head movement (Long & Wickens, 1994; Velger, 1998) and produce a mismatch between proprioception (sense of body...moves. Movement of the head will cause significant blurring, or loss of definition, if the full 16 msec hold-time is maintained. A new type of LCoS, a...system with proprioceptive information about viewing distance, then changes in accommodation or vergence can affect perceived size, depth, or speed

  18. Head-Worn Display Concepts for Surface Operations for Commerical Aircraft

    NASA Technical Reports Server (NTRS)

    Arthur, Jarvis J., III; Prinzel, Lawrence J., III; Bailey, Randall E.; Shelton, Kevin J.; Williams, Steven P.; Kramer, Lynda J.; Norman, Robert M.

    2008-01-01

    Experiments and flight tests have shown that a Head-Up Display (HUD) and a head-down electronic moving map (EMM) can be enhanced with Synthetic Vision for airport surface operations. While great success in ground operations was demonstrated with a HUD, the research noted that two major HUD limitations during ground operations were its monochrome form and limited, fixed field-of-regard. A potential solution to these limitations found with HUDs may be emerging with Head Worn Displays (HWDs). HWDs are small display devices that may be worn without significant encumbrance to the user. By coupling the HWD with a head tracker, unlimited field-of-regard may be realized. The results of three ground simulation experiments conducted at NASA Langley Research Center are summarized. The experiments evaluated the efficacy of head-worn display applications of Synthetic Vision and Enhanced Vision technology to improve transport aircraft surface operations. The results of the experiments showed that the fully integrated HWD provided greater pilot performance with respect to staying on the path compared to using paper charts alone. Further, when comparing the HWD with the HUD concept, there were no differences in path performance. In addition, the HWD and HUD concepts were rated via paired-comparisons the same in terms of situation awareness and workload.

  19. Alternative display and interaction devices

    NASA Technical Reports Server (NTRS)

    Bolas, M. T.; McDowall, I. E.; Mead, R. X.; Lorimer, E. R.; Hackbush, J. E.; Greuel, C.

    1995-01-01

    While virtual environment systems are typically thought to consist of a head mounted display and a flex-sensing glove, alternative peripheral devices are beginning to be developed in response to application requirements. Three such alternatives are discussed: fingertip sensing gloves, fixed stereoscopic viewers, and counterbalanced head mounted displays. A subset of commercial examples that highlight each alternative is presented as well as a brief discussion of interesting engineering and implementation issues.

  20. A Comparison of Head-Up and Head-Down Display Formats during Instrument Flying Tasks

    DTIC Science & Technology

    1992-11-01

    the radial from the station. The pointer consists of a SA bearing pointer, reference wings, and a readout. The pointer moves about the center of the...indicator to show the relative, magnetic bearing to the TACAN station. The readout displays the magnetic radial itom the i station, The pointer is...center of the Indicator, W 14. 1* W- Figure 4.11 .. Reftrence Tics 4,4,3. TACAN Radial Readout This readout, shown below, displays magnetic radial from

  1. Evaluation of Head-Worn Display Concepts for Commercial Aircraft Taxi Operations

    NASA Technical Reports Server (NTRS)

    Bailey, Randall E.; Arthur, Jarvis J., III; Prinzel, Lawrence J., III; Kramer, Lynda J.

    2007-01-01

    Previous research has demonstrated that a Head-Up Display (HUD) can be used to enable more capacity and safer aircraft surface operations. This previous research also noted that the HUD exhibited two major limitations which hindered the full potential of the display concept: 1) the monochrome HUD format; and, 2) a limited, fixed field of regard. Full-color Head Worn Displays (HWDs) with very small sizes and weights are emerging to the extent that this technology may be practical for commercial and business aircraft operations. By coupling the HWD with a head tracker, full-color, out-the-window display concepts with an unlimited field-of-regard may be realized to improve efficiency and safety in surface operations. A ground simulation experiment was conducted at NASA Langley to evaluate the efficacy of head-worn display applications which may directly address the limitations of the HUD while retaining all of its advantages in surface operations. The simulation experiment used airline crews to evaluate various displays (HUD, HWD) and display concepts in an operationally realistic environment by using a Chicago, O Hare airport database. The results pertaining to the implications of HWDs for commercial business and transport aviation applications are presented herein. Overall HWD system latency was measured and found to be acceptable, but not necessarily optimal. A few occurrences of simulator sickness were noted while wearing the HWD, but overall there appears to be commercial pilot acceptability and usability to the concept. Many issues were identified which need to be addressed in future research including continued reduction in user encumbrance due to the HWD, and improvement in image alignment, accuracy, and boresighting.

  2. Data Display Preference, Acceptability, and Accuracy among Urban Head Start Teachers

    ERIC Educational Resources Information Center

    Hojnoski, Robin L.; Caskie, Grace I. L.; Gischlar, Karen L.; Key, Jennifer M.; Barry, Amberly; Hughes, Cheyenne L.

    2009-01-01

    The ability to collect, organize graphically, understand, interpret, and use data to make decisions is becoming more central to the role of early childhood practitioners. One consideration in practitioner use of data is the acceptability of the method of data display. The purpose of this study was to explore Head Start teachers' preference for and…

  3. Effect on real-world depth perception from exposure to heads-down stereoscopic flight displays

    NASA Technical Reports Server (NTRS)

    Busquets, Anthony M.; Williams, Steven P.; Parrish, Russell V.

    1990-01-01

    A stereoacuity test was used as part of the experimental protocol of a study in which eight transport pilots flew repeated simulated landing approaches using both stereo and nonstereo three-dimensional heads-down 'pathway in the sky' displays. At the decisionmaking crux of each approach, the pilots transitioned to a stereoacuity test employing real objects rather than a two-dimensional target apparatus. A statistical analysis of stereoacuity measures which compared a controlled condition of no exposure to any electronic flight display with the transition data from nonstereo and stereopsis displays indicated no significant differences for any of the conditions.

  4. An intelligent system and a relational data base for codifying helmet-mounted display symbology design requirements

    NASA Astrophysics Data System (ADS)

    Rogers, Steven P.; Hamilton, David B.

    1994-06-01

    To employ the most readily comprehensible presentation methods and symbology with helmet-mounted displays (HMDs), it is critical to identify the information elements needed to perform each pilot function and to analytically determine the attributes of these elements. The extensive analyses of mission requirements currently performed for pilot-vehicle interface design can be aided and improved by the new capabilities of intelligent systems and relational databases. An intelligent system, named ACIDTEST, has been developed specifically for organizing and applying rules to identify the best display modalities, locations, and formats. The primary objectives of the ACIDTEST system are to provide rapid accessibility to pertinent display research data, to integrate guidelines from many disciplines and identify conflicts among these guidelines, to force a consistent display approach among the design team members, and to serve as an 'audit trail' of design decisions and justifications. A powerful relational database called TAWL ORDIR has been developed to document information requirements and attributes for use by ACIDTEST as well as to greatly augment the applicability of mission analysis data. TAWL ORDIR can be used to rapidly reorganize mission analysis data components for study, perform commonality analyses for groups of tasks, determine the information content requirement for tailored display modes, and identify symbology integration opportunities.

  5. Visual Discomfort with Stereo 3D Displays when the Head is Not Upright

    PubMed Central

    Kane, David; Held, Robert T.; Banks, Martin S.

    2012-01-01

    Properly constructed stereoscopic images are aligned vertically on the display screen, so on-screen binocular disparities are strictly horizontal. If the viewer’s inter-ocular axis is also horizontal, he/she makes horizontal vergence eye movements to fuse the stereoscopic image. However, if the viewer’s head is rolled to the side, the on-screen disparities now have horizontal and vertical components at the eyes. Thus, the viewer must make horizontal and vertical vergence movements to binocularly fuse the two images. Vertical vergence movements occur naturally, but they are usually quite small. Much larger movements are required when viewing stereoscopic images with the head rotated to the side. We asked whether the vertical vergence eye movements required to fuse stereoscopic images when the head is rolled cause visual discomfort. We also asked whether the ability to see stereoscopic depth is compromised with head roll. To answer these questions, we conducted behavioral experiments in which we simulated head roll by rotating the stereo display clockwise or counter-clockwise while the viewer’s head remained upright relative to gravity. While viewing the stimulus, subjects performed a psychophysical task. Visual discomfort increased significantly with the amount of stimulus roll and with the magnitude of on-screen horizontal disparity. The ability to perceive stereoscopic depth also declined with increasing roll and on-screen disparity. The magnitude of both effects was proportional to the magnitude of the induced vertical disparity. We conclude that head roll is a significant cause of viewer discomfort and that it also adversely affects the perception of depth from stereoscopic displays. PMID:24058723

  6. Visual Discomfort with Stereo 3D Displays when the Head is Not Upright.

    PubMed

    Kane, David; Held, Robert T; Banks, Martin S

    2012-02-09

    Properly constructed stereoscopic images are aligned vertically on the display screen, so on-screen binocular disparities are strictly horizontal. If the viewer's inter-ocular axis is also horizontal, he/she makes horizontal vergence eye movements to fuse the stereoscopic image. However, if the viewer's head is rolled to the side, the on-screen disparities now have horizontal and vertical components at the eyes. Thus, the viewer must make horizontal and vertical vergence movements to binocularly fuse the two images. Vertical vergence movements occur naturally, but they are usually quite small. Much larger movements are required when viewing stereoscopic images with the head rotated to the side. We asked whether the vertical vergence eye movements required to fuse stereoscopic images when the head is rolled cause visual discomfort. We also asked whether the ability to see stereoscopic depth is compromised with head roll. To answer these questions, we conducted behavioral experiments in which we simulated head roll by rotating the stereo display clockwise or counter-clockwise while the viewer's head remained upright relative to gravity. While viewing the stimulus, subjects performed a psychophysical task. Visual discomfort increased significantly with the amount of stimulus roll and with the magnitude of on-screen horizontal disparity. The ability to perceive stereoscopic depth also declined with increasing roll and on-screen disparity. The magnitude of both effects was proportional to the magnitude of the induced vertical disparity. We conclude that head roll is a significant cause of viewer discomfort and that it also adversely affects the perception of depth from stereoscopic displays.

  7. Flight Test of a Head-Worn Display as an Equivalent-HUD for Terminal Operations

    NASA Technical Reports Server (NTRS)

    Shelton, K. J.; Arthur, J. J., III; Prinzel, L. J., III; Nicholas, S. N.; Williams, S. P.; Bailey, R. E.

    2015-01-01

    Research, development, test, and evaluation of flight deck interface technologies is being conducted by NASA to proactively identify, develop, and mature tools, methods, and technologies for improving overall aircraft safety of new and legacy vehicles operating in the Next Generation Air Transportation System (NextGen). Under NASA's Aviation Safety Program, one specific area of research is the use of small Head-Worn Displays (HWDs) as a potential equivalent display to a Head-up Display (HUD). Title 14 of the US CFR 91.175 describes a possible operational credit which can be obtained with airplane equipage of a HUD or an "equivalent"' display combined with Enhanced Vision (EV). A successful HWD implementation may provide the same safety and operational benefits as current HUD-equipped aircraft but for significantly more aircraft in which HUD installation is neither practical nor possible. A flight test was conducted to evaluate if the HWD, coupled with a head-tracker, can provide an equivalent display to a HUD. Approach and taxi testing was performed on-board NASA's experimental King Air aircraft in various visual conditions. Preliminary quantitative results indicate the HWD tested provided equivalent HUD performance, however operational issues were uncovered. The HWD showed significant potential as all of the pilots liked the increased situation awareness attributable to the HWD's unique capability of unlimited field-of-regard.

  8. The design and fabrication of an optical diffuser for head-up displays

    NASA Astrophysics Data System (ADS)

    Lee, Chi-Hung; Chou, Ming-Chieh; Chen, Yi-Cheng

    2015-03-01

    Laser scanning head-up display (HUD) is an off-axis imaging virtual image display system. Its optical design inherited the feature of head-up display architecture in a fighter. When it is applied to a car, its main optics is replaced by a mirror to save space. Usually, a diffusion sheet or frosted glass is placed in front of a pico-projector to be an image screen, but there will be an issue of lower sharpness of the image due to its low divergence ability for the incident beam. This study proposes a pyramid-shaped micro-structure optical diaphragm to replace the above traditional diffusion films. Besides, the relationship between the optical light path and microstructure in the HUD is also well described.

  9. Evaluation of the Microvision Spectrum SD2500 Helmet-Mounted Display for the Air Warrior Block 3 Day/Night HMD Program

    DTIC Science & Technology

    2006-03-01

    USAARL Report No. 2006-08 Evaluation of the Microvision Spectrum SD2500 Helmet-Mounted Display for the Air Warrior Block 3 Day/Night HMD Program by... Microvision Spectrum SD2500 Helmet-Mounted Display for the Air PE 622787 Warrior Block 3 Day/Night HMD Program PR 879 TA P WU DA361539 6. AUTHOR(S) Clarence E...ABSTRACT (Maximum 200 words) The Microvision Spectrum SD2500 HMD, a monocular, full-color scanning laser display, display, was evaluated for optical image

  10. A Real-Time Optical 6D Tracker for Head-Mounted Display Systems

    DTIC Science & Technology

    1990-03-01

    prototype uses off-the-shelf components and can be easily duplicated. Our results indicate that the new system significantly out-performs other existing... indicate that the Polhemus can provide about 16 position updates per second, and the lag in response can be as long as 120 milliseconds. 2.1.3 Mechanical...of rotational accuracy and 1cm of positional accuracy with this camera self-calibration process (Section 3.4.2). Our experience indicates that in order

  11. Jedi training: playful evaluation of head-mounted augmented reality display systems

    NASA Astrophysics Data System (ADS)

    Ozbek, Christopher S.; Giesler, Bjorn; Dillmann, Ruediger

    2004-05-01

    A fundamental decision in building augmented reality (AR) systems is how to accomplish the combining of the real and virtual worlds. Nowadays this key-question boils down to the two alternatives video-see-through (VST) vs. optical-see-through (OST). Both systems have advantages and disadvantages in areas like production-simplicity, resolution, flexibility in composition strategies, field of view etc. To provide additional decision criteria for high dexterity, accuracy tasks and subjective user-acceptance a gaming environment was programmed that allowed good evaluation of hand-eye coordination, and that was inspired by the Star Wars movies. During an experimentation session with more than thirty participants a preference for optical-see-through glasses in conjunction with infra-red-tracking was found. Especially the high-computational demand for video-capture, processing and the resulting drop in frame rate emerged as a key-weakness of the VST-system.

  12. Game-Based Evacuation Drill Using Augmented Reality and Head-Mounted Display

    ERIC Educational Resources Information Center

    Kawai, Junya; Mitsuhara, Hiroyuki; Shishibori, Masami

    2016-01-01

    Purpose: Evacuation drills should be more realistic and interactive. Focusing on situational and audio-visual realities and scenario-based interactivity, the authors have developed a game-based evacuation drill (GBED) system that presents augmented reality (AR) materials on tablet computers. The paper's current research purpose is to improve…

  13. Instrumentation and Tactor Considerations for a Head-Mounted Tactile Display

    DTIC Science & Technology

    2008-09-01

    S2 allow 2AFC [two alternate forced choice] decisions to be made in time or in location. For more detailed localization choices, an external keypad...Additional switches are connected to connector J2 to support detection and localization experiments: the two hand switches, S1 and S2 allow 2AFC

  14. Multi-user 3D display using a head tracker and RGB laser illumination source

    NASA Astrophysics Data System (ADS)

    Surman, Phil; Sexton, Ian; Hopf, Klaus; Bates, Richard; Lee, Wing Kai; Buckley, Edward

    2007-05-01

    A glasses-free (auto-stereoscopic) 3D display that will serve several viewers who have freedom of movement over a large viewing region is described. This operates on the principle of employing head position tracking to provide regions referred to as exit pupils that follow the positions ofthe viewers' eyes in order for appropriate left and right images to be seen. A non-intrusive multi-user head tracker controls the light sources of a specially designed backlight that illuminates a direct-view LCD.

  15. An Optical Analysis of the Farrand VCASS (Visually Coupled Airborne Systems Simulator) Helmet-Mounted Display

    DTIC Science & Technology

    1983-10-01

    helmet, without . display, at 0.7 kg (24.5 oz), with center of gravity located at X +1.16 cm (0.46 in.) and Y - +1.72 cm (0.68 in.) relative to the...8217J-4 417-70 noJ 4 - Y 00--- - - - - - /33 PANCAKE WINDOWTM 15-MM DIAMETER BEAM COMBINER EXIT PUPIL POLARI ZER RELAY OPTICS FIBEROPTIC FOLDING PRISM...TEE LEFT - DIMENSIIOS ARE GIVEN I MILLIMETERS - TEICKNESS IS AIAL SITANCE TO RlET SURFACE ASPHERIC CONSTANTS _ 2 (CURv) Y 4 6 o 10

  16. A full-color wide-field-of-view holographic helmet-mounted display for pilot/vehicle interface development and human factors studies

    NASA Technical Reports Server (NTRS)

    Burley, James R., II; Larussa, Joseph A.

    1990-01-01

    The application of advanced display concepts and helmet-mounted display (HMD) technology to air-to-air combat in highly maneuverable aircraft is discussed. The concepts considered include control authority, aircraft attitude, and energy maneuverability, and an HMD system designed for simulation studies is described. The human factors issues involved are addressed.

  17. Head-up display using an inclined Al2O3 column array.

    PubMed

    Cho, Wen-Hao; Lee, Chao-Te; Kei, Chi-Chung; Liao, Bo-Huei; Chiang, Donyau; Lee, Cheng-Chung

    2014-02-01

    An orderly inclined Al2O3 column array was fabricated by atomic layer deposition and sequential electron beam evaporation using a hollow nanosphere template. The transmittance spectra at various angles of incidence were obtained through the use of a Perkin-Elmer Lambda 900 UV/VIS/NIR spectrometer. The inclined column array could display the image information through a scattering mechanism and was transparent at high viewing angles along the deposition plane. This characteristic of the inclined column array gives it potential for applications in head-up displays in the automotive industry.

  18. Head-Up Auditory Displays for Traffic Collision Avoidance System Advisories: A Preliminary Investigation

    NASA Technical Reports Server (NTRS)

    Begault, Durand R.

    1993-01-01

    The advantage of a head-up auditory display was evaluated in a preliminary experiment designed to measure and compare the acquisition time for capturing visual targets under two auditory conditions: standard one-earpiece presentation and two-earpiece three-dimensional (3D) audio presentation. Twelve commercial airline crews were tested under full mission simulation conditions at the NASA-Ames Man-Vehicle Systems Research Facility advanced concepts flight simulator. Scenario software generated visual targets corresponding to aircraft that would activate a traffic collision avoidance system (TCAS) aural advisory; the spatial auditory position was linked to the visual position with 3D audio presentation. Results showed that crew members using a 3D auditory display acquired targets approximately 2.2 s faster than did crew members who used one-earpiece head- sets, but there was no significant difference in the number of targets acquired.

  19. Project plan for joint FAA/NASA head-up display concept evaluation

    NASA Technical Reports Server (NTRS)

    Haines, R. F.

    1978-01-01

    Head-Up Display (HUD) concept for large commercial turbojet transport aircraft is considered for the its contribution to aviation safety in the form of improved performance during the approach and landing phase flight. The basic reearch areas represent fundamental questions that are still unresolved and which were considered important to the effective use of the HUD by pilots. Project documentation and management responsibilities are outlined.

  20. Update of the AN/AVS-7 Head-Up Display program

    NASA Astrophysics Data System (ADS)

    Nicholson, Robert K.; Troxel, David

    1996-06-01

    The AN/AVS-7 head up display (HUD) system is designed to enhance night vision goggle pilotage by superimposing aircraft, navigation and flight symbology on the aviator's night vision imaging system. The AN/AVS-7 system is produced by AEL Industries Inc., Cross Systems Division under a five year production contract with the Army's Communications and Electronics Command. The program is managed by the Army's Project Manager for Night Vision, Reconnaissance, Surveillance and Target Acquisition.

  1. Synthetic Vision Enhanced Surface Operations With Head-Worn Display for Commercial Aircraft

    NASA Technical Reports Server (NTRS)

    Arthur, Jarvis J., III; Prinzel, Lawrence J., III; Shelton, Kevin J.; Kramer, Lynda J.; Williams, Steven P.; Bailey, Randall E.; Norman, R. M.

    2007-01-01

    Experiments and flight tests have shown that airport surface operations can be enhanced by using synthetic vision and associated technologies, employed on a Head-Up Display (HUD) and head-down display electronic moving maps (EMM). Although HUD applications have shown the greatest potential operational improvements, the research noted that two major limitations during ground operations were its monochrome form and limited, fixed field-of-regard. A potential solution to these limitations may be the application of advanced Head Worn Displays (HWDs) particularly during low-visibility operations wherein surface movement is substantially limited because of the impaired vision of pilots and air traffic controllers. The paper describes the results of ground simulation experiments conducted at the NASA Langley Research Center. The results of the experiments showed that the fully integrated HWD concept provided significantly improved path performance compared to using paper charts alone. When comparing the HWD and HUD concepts, there were no statistically-significant differences in path performance or subjective ratings of situation awareness and workload. Implications and directions for future research are described.

  2. Three-dimensional audio versus head-down traffic alert and collision avoidance system displays.

    PubMed

    Begault, D R; Pittman, M T

    1996-01-01

    The advantage of a head-up auditory display for situational awareness was evaluated in an experiment designed to measure and compare the acquisition time for capturing visual targets under two conditions: standard head-down Traffic Alert and Collision Avoidance System display and three-dimensional (3-D) audio Traffic Alert and Collision Avoidance System presentation. (The technology used for 3-D audio presentation allows a stereo headphone user to potentially localize a sound at any externalized position in 3-D auditory space). Ten commercial airline crews were tested under full-mission simulation conditions at the NASA-Ames Crew-Vehicle Systems Research Facility Advanced Concepts Flight Simulator. Scenario software generated targets corresponding to aircraft that activated a 3-D aural advisory (the head-up auditory condition) or a standard, visual-audio TCAS advisory (map display with monaural audio alert). Results showed a significant difference in target acquisition time between the two conditions, favoring the 3-D audio Traffic Alert and Collision Avoidance System condition by 500 ms.

  3. Human-machine interface issues in the use of helmet-mounted displays in short conjugate simulators

    NASA Astrophysics Data System (ADS)

    Melzer, James E.

    2011-06-01

    With the introduction of helmet-mounted displays (HMD) into modern aircraft, there is a desire on the part of pilot trainees to achieve a "look and feel" for the simulation environment similar to the real flight hardware. Given this requirement for high fidelity, it may be necessary to configure - or to perhaps re-configure - the HMD for a short conjugate viewing distance and to do so without causing eye strain or other adverse physiological effects. This paper will survey the human factors literature and provide an analysis on the visual construct issues of focus and vergence which - if not properly configured for the short conjugate simulator - could cause adverse effects, which can negatively affect training.

  4. Perceptual and cognitive effects on the use of helmet-mounted displays due to external operational factors

    NASA Astrophysics Data System (ADS)

    Harding, Thomas H.; Rash, Clarence E.; Lang, Gregory T.

    2010-04-01

    This paper addresses the human component of the human-machine interface and the effects of operational stressors on the user as a system operator. Discussions will strive to link operational stress factors to perception, cognition, and human performance errors and their implications for the design of helmet-mounted displays (HMDs). While many operational stressors can be self-imposed (e.g., fatigue, medication use and smoking), this discussion will focus on environment-related (external) stressors. Generally these factors are characteristics of an environment that require unique countermeasure development versus being under the direct control of the user. These include altitude, noise, vibration, thermal extremes and ambient lighting. Thus, it becomes incumbent upon the HMD designers to be cognizant of these environmental stressors and understand how the Soldier will perform when exposed to these conditions.

  5. Helmet-mounted tracker and display (HMT/D) interfaces: developing a standardized helmet-vehicle interface (HVI)

    NASA Astrophysics Data System (ADS)

    Kocian, Dean F.

    1998-08-01

    The successful integration of technology and human factors meets its ultimate challenge in the area of military performance. Nowhere are the stakes so high and the competition so rigorous as in the arena of combat. This paper documents the attempt to define, develop, and test a 'standardized' interface for helmet-mounted tracker and displays as these systems begin to phase into the military inventory as standard equipment for USAF and USN fighter aircraft. The design that has been evolved is based upon active use and refinement in an environment that is as close to combat conditions, as resources permit. Many of the design ideas and lessons-learned covered in this paper came either directly or indirectly from pilots and support personnel of the USAF 422 Test and Evaluation Squadron located at Nellis AFB, NV.

  6. Evaluation of Head Mounted and Head Down Information Displays During Simulated Mine-Countermeasures Dives to 42 msw

    DTIC Science & Technology

    2008-04-01

    information processing is slowed at each stage by narcosis ( nitrogen and carbon dioxide). It is likely that transferring information from sensory memory to...short term memory. Background noise is likely a factor in distracting the diver from attending to other, important information. Pressure ( narcosis ...Immersion in water increases the ambient pressure of the diving environment and may lead to narcosis . According to Fowler et al., (1985

  7. Head-up displays and their automotive application: an overview of human factors issues affecting safety.

    PubMed

    Ward, N J; Parkes, A

    1994-12-01

    In response to the recent innovations to use head-up displays (HUDs) in vehicles, this paper discusses the relevant human factors issues arising from this display format and the potential safety implications. A review is made of the relevant HUD literature, primarily from the aviation field. The primary issues for automotive HUDs relevant to system performance and safety in the driving task involve interference from background scene complexity, system novelty, user perceptual style, cognitive disruption, and perceptual tunnelling. Basic research is necessary to investigate the extent of these issues as well as to resolve fundamental design specifications (e.g. HUD size, shape, placement, information content). It is suggested that the introduction of HUDs into vehicles be carefully considered. This will necessitate not only the reconsideration what constitutes an in-vehicle display, but also what constitutes the information to be conveyed.

  8. Terrain Portrayal for Synthetic Vision Systems Head-Down Displays Evaluation Results

    NASA Technical Reports Server (NTRS)

    Hughes, Monica F.; Glaab, Louis J.

    2007-01-01

    A critical component of SVS displays is the appropriate presentation of terrain to the pilot. At the time of this study, the relationship between the complexity of the terrain presentation and resulting enhancements of pilot SA and pilot performance had been largely undefined. The terrain portrayal for SVS head-down displays (TP-HDD) simulation examined the effects of two primary elements of terrain portrayal on the primary flight display (PFD): variations of digital elevation model (DEM) resolution and terrain texturing. Variations in DEM resolution ranged from sparsely spaced (30 arc-sec) to very closely spaced data (1 arc-sec). Variations in texture involved three primary methods: constant color, elevation-based generic, and photo-realistic, along with a secondary depth cue enhancer in the form of a fishnet grid overlay.

  9. High brightness MEMS mirror based head-up display (HUD) modules with wireless data streaming capability

    NASA Astrophysics Data System (ADS)

    Milanovic, Veljko; Kasturi, Abhishek; Hachtel, Volker

    2015-02-01

    A high brightness Head-Up Display (HUD) module was demonstrated with a fast, dual-axis MEMS mirror that displays vector images and text, utilizing its ~8kHz bandwidth on both axes. Two methodologies were evaluated: in one, the mirror steers a laser at wide angles of <48° on transparent multi-color fluorescent emissive film and displays content directly on the windshield, and in the other the mirror displays content on reflective multi-color emissive phosphor plates reflected off the windshield to create a virtual image for the driver. The display module is compact, consisting of a single laser diode, off-the-shelf lenses and a MEMS mirror in combination with a MEMS controller to enable precise movement of the mirror's X- and Y-axis. The MEMS controller offers both USB and wireless streaming capability and we utilize a library of functions on a host computer for creating content and controlling the mirror. Integration with smart phone applications is demonstrated, utilizing the mobile device both for content generation based on various messages or data, and for content streaming to the MEMS controller via Bluetooth interface. The display unit is highly resistant to vibrations and shock, and requires only ~1.5W to operate, even with content readable in sunlit outdoor conditions. The low power requirement is in part due to a vector graphics approach, allowing the efficient use of laser power, and also due to the use of a single, relatively high efficiency laser and simple optics.

  10. Studying complex decision making in natural settings: using a head-mounted video camera to study competitive orienteering.

    PubMed

    Omodei, M M; McLennan, J

    1994-12-01

    Head-mounted video recording is described as a potentially powerful method for studying decision making in natural settings. Most alternative data-collection procedures are intrusive and disruptive of the decision-making processes involved while conventional video-recording procedures are either impractical or impossible. As a severe test of the robustness of the methodology we studied the decision making of 6 experienced orienteers who carried a head-mounted light-weight video camera as they navigated, running as fast as possible, around a set of control points in a forest. Use of the Wilcoxon matched-pairs signed-ranks test indicated that compared with free recall, video-assisted recall evoked (a) significantly greater experiential immersion in the recall, (b) significantly more specific recollections of navigation-related thoughts and feelings, (c) significantly more realizations of map and terrain features and aspects of running speed which were not noticed at the time of actual competition, and (d) significantly greater insight into specific navigational errors and the intrusion of distracting thoughts into the decision-making process. Potential applications of the technique in (a) the environments of emergency services, (b) therapeutic contexts, (c) education and training, and (d) sports psychology are discussed.

  11. Terrain Portrayal for Synthetic Vision Systems Head-Down Displays Evaluation Results: Compilation of Pilot Transcripts

    NASA Technical Reports Server (NTRS)

    Hughes, Monica F.; Glaab, Louis J.

    2007-01-01

    The Terrain Portrayal for Head-Down Displays (TP-HDD) simulation experiment addressed multiple objectives involving twelve display concepts (two baseline concepts without terrain and ten synthetic vision system (SVS) variations), four evaluation maneuvers (two en route and one approach maneuver, plus a rare-event scenario), and three pilot group classifications. The TP-HDD SVS simulation was conducted in the NASA Langley Research Center's (LaRC's) General Aviation WorkStation (GAWS) facility. The results from this simulation establish the relationship between terrain portrayal fidelity and pilot situation awareness, workload, stress, and performance and are published in the NASA TP entitled Terrain Portrayal for Synthetic Vision Systems Head-Down Displays Evaluation Results. This is a collection of pilot comments during each run of the TP-HDD simulation experiment. These comments are not the full transcripts, but a condensed version where only the salient remarks that applied to the scenario, the maneuver, or the actual research itself were compiled.

  12. High color fidelity thin film multilayer systems for head-up display use

    NASA Astrophysics Data System (ADS)

    Tsou, Yi-Jen D.; Ho, Fang C.

    1996-09-01

    Head-up display is gaining increasing access in automotive vehicles for indication and position/navigation purposes. An optical combiner, which allows the driver to receive image information from outside and inside of the automobile, is the essential part of this display device. Two multilayer thin film combiner coating systems with distinctive polarization selectivity and broad band spectral neutrality are discussed. One of the coating systems was designed to be located at the lower portion of the windshield. The coating reduced the exterior glare by approximately 45% and provided about 70% average see-through transmittance in addition to the interior information display. The other coating system was designed to be integrated with the sunshield located at the upper portion of the windshield. The coating reflected the interior information display while reducing direct sunlight penetration to 25%. Color fidelity for both interior and exterior images were maintained in both systems. This facilitated the display of full-color maps. Both coating systems were absorptionless and environmentally durable. Designs, fabrication, and performance of these coating systems are addressed.

  13. Biodynamic simulations of the effect of a neck-mounted air bag on the head/neck response during high G acceleration.

    PubMed

    Lee, C M; Freivalds, A; Lee, S Y

    1991-08-01

    New helmet-mounted devices (such as night-vision goggles, laser eye protection, etc.) have created new safety hazards for pilots during ejection or high G maneuvering. In order to prevent the resulting head/neck injuries, this study extends the air-bag protection system developed for ground vehicles to a neck mounted system for aircrew personnel. Results, carried out by computer biodynamic simulations using the Articulated Total Body Model (ATB), showed that: 1) helmet weight had little effect on head/neck torque, contact force and flexion angle; 2) initial head/neck position and center of gravity offsets of the helmet-mounted devices had significant effects on head-neck torques, contact forces, and neck flexion angles; and 3) the neck mounted air bag significantly reduced neck torques, contact forces, and neck flexion angles. We conclude that the neck-mounted air bag system could significantly reduce the severity of head/neck injuries to pilots during ejection or high G maneuvering.

  14. Some VTOL head-up display drive-law problems and solutions

    NASA Technical Reports Server (NTRS)

    Merrick, Vernon K.

    1993-01-01

    A piloted simulation test was conducted on the Ames Research Center's vertical motion simulator (VMS) in support of the Phase 2A flight test of NASA's V/STOL systems research aircraft (VSRA). During the simulation several problems were found with the head-up display (HUD) symbol drive laws and the flightpath synthesis. These problems and the solutions devised to solve them are described. Most of the resulting HUD drive-law changes were implemented during the simulation and their effectiveness was verified. Subsequently both the HUD symbol drive-law and flightpath-synthesis changes were implemented in the VSRA and tested successfully in the Phase 2A flight tests.

  15. An exploratory simulation study of a head-up display for general aviation lightplanes

    NASA Technical Reports Server (NTRS)

    Harris, R. L., Sr.; Hewes, D. E.

    1973-01-01

    The concept of a simplified head-up display referred to as a landing-site indicator (LASI) for use in lightplanes is discussed. Results of a fixed-base simulation study exploring the feasibility of the LASI concept are presented in terms of measurements of pilot performance, control-activity parameters, and subjective comments of four test subjects. These subjects, all of whom had various degrees of piloting experience in this type aircraft, performed a series of simulated landings both with and without the LASI starting from different initial conditions in the final approach leg of the landing maneuver.

  16. Head-up auditory displays for traffic collision avoidance system advisories: a preliminary investigation.

    PubMed

    Begault, D R

    1993-12-01

    The advantage of a head-up auditory display was evaluated in a preliminary experiment designed to measure and compare the acquisition time for capturing visual targets under two auditory conditions: standard one-earpiece presentation and two-earpiece three-dimensional (3D) audio presentation. Twelve commercial airline crews were tested under full mission simulation conditions at the NASA-Ames Man-Vehicle Systems Research Facility advanced concepts flight simulator. Scenario software generated visual targets corresponding to aircraft that would activate a traffic collision avoidance system (TCAS) aural advisory; the spatial auditory position was linked to the visual position with 3D audio presentation. Results showed that crew members using a 3D auditory display acquired targets approximately 2.2 s faster than did crew members who used one-earpiece headsets, but there was no significant difference in the number of targets acquired.

  17. A head-up display for mid-air drone recovery

    NASA Technical Reports Server (NTRS)

    Augustine, W. L.; Heft, E. L.; Bowen, T. E.; Newman, R. L.

    1978-01-01

    During mid-air retrieval of parachute packages, the absence of a natural horizon creates serious difficulties for the pilot of the recovery helicopter. A head-up display (HUD) was tested in an attempt to solve this problem. Both a roll-stabilized HUD and a no-roll (pitch only) HUD were tested. The results show that fewer missed passes occurred with the roll-stabilized HUD when the horizon was obscured. The pilots also reported that the workload was greatly reduced. Roll-stabilization was required to prevent vertigo when flying in the absence of a natural horizon. Any HUD intended for mid-air retrieval should display pitch, roll, sideslip, airspeed, and vertical velocity.

  18. A head up display format for application to V/STOL aircraft approach and landing

    NASA Technical Reports Server (NTRS)

    Merrick, Vernon K.; Farris, Glenn G.; Vanags, Andrejs A.

    1990-01-01

    A head up display (HUD) format developed at NASA Ames Research Center to provide pilots of V/STOL aircraft with complete flight guidance and control information for category-3C terminal-area flight operations, is described in detail. These flight operations cover a large spectrum, from STOL operations on land-based runways to VTOL operations on small ships in high seas. Included in this description is a complete geometrical specification of the HUD elements and their drive laws. The principal features of this display format are the integration of the flightpath and pursuit guidance information into a narrow field of view, easily assimilated by the pilot with a single glance, and the superposition of vertical and horizontal situation information. The display is a derivative of a successful design developed for conventional transport aircraft. The design is the outcome of many piloted simulations conducted over a four-year period. Whereas the concepts on which the display format rests could not be fully exploited because of field-of-view restrictions, and some reservations remain about the acceptability of superimposing vertical and horizontal situation information, the design successfully fulfilled its intended objectives.

  19. Novel microscope-integrated stereoscopic heads-up display for intrasurgical optical coherence tomography.

    PubMed

    Shen, Liangbo; Carrasco-Zevallos, Oscar; Keller, Brenton; Viehland, Christian; Waterman, Gar; Hahn, Paul S; Kuo, Anthony N; Toth, Cynthia A; Izatt, Joseph A

    2016-05-01

    Intra-operative optical coherence tomography (OCT) requires a display technology which allows surgeons to visualize OCT data without disrupting surgery. Previous research and commercial intrasurgical OCT systems have integrated heads-up display (HUD) systems into surgical microscopes to provide monoscopic viewing of OCT data through one microscope ocular. To take full advantage of our previously reported real-time volumetric microscope-integrated OCT (4D MIOCT) system, we describe a stereoscopic HUD which projects a stereo pair of OCT volume renderings into both oculars simultaneously. The stereoscopic HUD uses a novel optical design employing spatial multiplexing to project dual OCT volume renderings utilizing a single micro-display. The optical performance of the surgical microscope with the HUD was quantitatively characterized and the addition of the HUD was found not to substantially effect the resolution, field of view, or pincushion distortion of the operating microscope. In a pilot depth perception subject study, five ophthalmic surgeons completed a pre-set dexterity task with 50.0% (SD = 37.3%) higher success rate and in 35.0% (SD = 24.8%) less time on average with stereoscopic OCT vision compared to monoscopic OCT vision. Preliminary experience using the HUD in 40 vitreo-retinal human surgeries by five ophthalmic surgeons is reported, in which all surgeons reported that the HUD did not alter their normal view of surgery and that live surgical maneuvers were readily visible in displayed stereoscopic OCT volumes.

  20. Novel microscope-integrated stereoscopic heads-up display for intrasurgical optical coherence tomography

    PubMed Central

    Shen, Liangbo; Carrasco-Zevallos, Oscar; Keller, Brenton; Viehland, Christian; Waterman, Gar; Hahn, Paul S.; Kuo, Anthony N.; Toth, Cynthia A.; Izatt, Joseph A.

    2016-01-01

    Intra-operative optical coherence tomography (OCT) requires a display technology which allows surgeons to visualize OCT data without disrupting surgery. Previous research and commercial intrasurgical OCT systems have integrated heads-up display (HUD) systems into surgical microscopes to provide monoscopic viewing of OCT data through one microscope ocular. To take full advantage of our previously reported real-time volumetric microscope-integrated OCT (4D MIOCT) system, we describe a stereoscopic HUD which projects a stereo pair of OCT volume renderings into both oculars simultaneously. The stereoscopic HUD uses a novel optical design employing spatial multiplexing to project dual OCT volume renderings utilizing a single micro-display. The optical performance of the surgical microscope with the HUD was quantitatively characterized and the addition of the HUD was found not to substantially effect the resolution, field of view, or pincushion distortion of the operating microscope. In a pilot depth perception subject study, five ophthalmic surgeons completed a pre-set dexterity task with 50.0% (SD = 37.3%) higher success rate and in 35.0% (SD = 24.8%) less time on average with stereoscopic OCT vision compared to monoscopic OCT vision. Preliminary experience using the HUD in 40 vitreo-retinal human surgeries by five ophthalmic surgeons is reported, in which all surgeons reported that the HUD did not alter their normal view of surgery and that live surgical maneuvers were readily visible in displayed stereoscopic OCT volumes. PMID:27231616

  1. Advanced Pathway Guidance Evaluations on a Synthetic Vision Head-Up Display

    NASA Technical Reports Server (NTRS)

    Kramer, Lynda J.; Prinzel, Lawrence J., III; Arthur, Jarvis J., III; Bailey, Randall E.

    2005-01-01

    NASA's Synthetic Vision Systems (SVS) project is developing technologies with practical applications to potentially eliminate low visibility conditions as a causal factor to civil aircraft accidents while replicating the operational benefits of clear day flight operations, regardless of the actual outside visibility condition. A major thrust of the SVS project involves the development/demonstration of affordable, certifiable display configurations that provide intuitive out-the-window terrain and obstacle information with advanced guidance for commercial and business aircraft. This experiment evaluated the influence of different pathway and guidance display concepts upon pilot situation awareness (SA), mental workload, and flight path tracking performance for Synthetic Vision display concepts using a Head-Up Display (HUD). Two pathway formats (dynamic and minimal tunnel presentations) were evaluated against a baseline condition (no tunnel) during simulated instrument meteorological conditions approaches to Reno-Tahoe International airport. Two guidance cues (tadpole, follow-me aircraft) were also evaluated to assess their influence. Results indicated that the presence of a tunnel on an SVS HUD had no effect on flight path performance but that it did have significant effects on pilot SA and mental workload. The dynamic tunnel concept with the follow-me aircraft guidance symbol produced the lowest workload and provided the highest SA among the tunnel concepts evaluated.

  2. The utility of Head-Up Displays - Eye-focus vs decision times

    NASA Technical Reports Server (NTRS)

    Weintraub, D. J.; Haines, R. F.; Randle, R. J.

    1984-01-01

    Instrument-panel information is presented by a Head-Up Display (HUD) to pilots in such a way that the symbols appear far away (at optical infinity) superimposed upon the landscape. The use of a HUD makes it, therefore, unnecessary for the pilot to take his eyes off the changing scene in order to look down and refocus on the instrument panel. It is pointed out that the HUD has proved superior to the conventional instrument-panel display. An experiment was conducted with the objective to help to determine which of the differences between HUD and conventional instrument-panel display are mainly responsible for the superiority of the HUD. Important features of this experiment are that the format of each virtual-image display, its luminance, and its angle subtended at the eye, remained the same as the optical distance and location were varied. It was found that the HUD symbology at optical infinity does reduce decision times compared to the same format at the location of a conventional instrument panel.

  3. Simulation evaluation of a low-altitude helicopter flight guidance system adapted for a helmet-mounted display

    NASA Technical Reports Server (NTRS)

    Swenson, Harry N.; Zelenka, Richard E.; Hardy, Gordon H.; Dearing, Munro G.

    1992-01-01

    A computer aiding concept for low-altitude helicopter flight was developed and evaluated in a real-time piloted simulation. The concept included an optimal control trajectory-generation algorithm based upon dynamic programming and a helmet-mounted display (HMD) presentation of a pathway-in-the-sky, a phantom aircraft, and flight-path vector/predictor guidance symbology. The trajectory-generation algorithm uses knowledge of the global mission requirements, a digital terrain map, aircraft performance capabilities, and advanced navigation information to determine a trajectory between mission way points that seeks valleys to minimize threat exposure. The pilot evaluation was conducted at NASA ARC moving base Vertical Motion Simulator (VMS) by pilots representing NASA, the U.S. Army, the Air Force, and the helicopter industry. The pilots manually tracked the trajectory generated by the algorithm utilizing the HMD symbology. The pilots were able to satisfactorily perform the tracking tasks while maintaining a high degree of awareness of the outside world.

  4. Development of a Flyable Acousto-Optic Laser Beam Deflection System for a Head Up Display of the Future.

    DTIC Science & Technology

    Rayleigh criteria). The system was designed for stroke writing but was demonstrated with lissajous writing. The acousto - optic deflectors employed...The report describes a laser display which is to be used in a Head-Up Display of the future. The uniqueness of the display is that it uses acousto ... optic components for the modulation and deflection of the laser beam. As a result, there are no moving parts, which increases the reliability and life

  5. Integration of Head-Up Display system in automotive industry: a generalized application

    NASA Astrophysics Data System (ADS)

    Betancur, J. Alejandro; Osorio, Gilberto; Mejía, Alejandro

    2013-06-01

    Throughout the development of the automotive industry, supporting activities related with driving has been material of analysis and experimentation, always seeking new ways to achieve greater safety for the driver and passengers. With the purpose of contributing to this topic, in order to contribute to this subject, this paper summarizes from past research experiences the use of Head-Up Display systems applied to the automobile industry, covering it from two main points of discussion: the first one, from a technical point of view, in which the main principles of optical design associated with a moderate-cost experimental set up are brought out; and the second one, an operational approach where an applied driving graphical interface is presented. Up to now, the results suggest that the experimental set up here discussed could be adaptable to any automobile vehicle, but it is needed further research and investment.

  6. An externally head-mounted wireless neural recording device for laboratory animal research and possible human clinical use.

    PubMed

    Yin, Ming; Li, Hao; Bull, Christopher; Borton, David A; Aceros, Juan; Larson, Lawrence; Nurmikko, Arto V

    2013-01-01

    In this paper we present a new type of head-mounted wireless neural recording device in a highly compact package, dedicated for untethered laboratory animal research and designed for future mobile human clinical use. The device, which takes its input from an array of intracortical microelectrode arrays (MEA) has ninety-seven broadband parallel neural recording channels and was integrated on to two custom designed printed circuit boards. These house several low power, custom integrated circuits, including a preamplifier ASIC, a controller ASIC, plus two SAR ADCs, a 3-axis accelerometer, a 48MHz clock source, and a Manchester encoder. Another ultralow power RF chip supports an OOK transmitter with the center frequency tunable from 3GHz to 4GHz, mounted on a separate low loss dielectric board together with a 3V LDO, with output fed to a UWB chip antenna. The IC boards were interconnected and packaged in a polyether ether ketone (PEEK) enclosure which is compatible with both animal and human use (e.g. sterilizable). The entire system consumes 17mA from a 1.2Ahr 3.6V Li-SOCl2 1/2AA battery, which operates the device for more than 2 days. The overall system includes a custom RF receiver electronics which are designed to directly interface with any number of commercial (or custom) neural signal processors for multi-channel broadband neural recording. Bench-top measurements and in vivo testing of the device in rhesus macaques are presented to demonstrate the performance of the wireless neural interface.

  7. Helmet-Mounted Display Research Capabilities of the NASA/Army Rotorcraft Aircrew Systems Concepts Airborne Laboratory (RASCAL)

    NASA Technical Reports Server (NTRS)

    Jacobsen, R. A.; Bivens, C. C.; Rediess, N. A.; Hindson, W. S.; Aiken, E. W.; Aiken, Edwin W. (Technical Monitor)

    1995-01-01

    The Rotorcraft Aircrew Systems Concepts Airborne Laboratory (RASCAL) is a UH-60A Black Hawk helicopter that is being modified by the US Army and NASA for flight systems research. The principal systems that are being installed in the aircraft are a Helmet Mounted Display (HMD) and imaging system, and a programmable full authority Research Flight Control System (RFCS). In addition, comprehensive instrumentation of both the rigid body of the helicopter and the rotor system is provided. The paper will describe the capabilities of these systems and their current state of development. A brief description of initial research applications is included. The wide (40 X 60 degree) field-of-view HMD system has been provided by Kaiser Electronics. It can be configured as a monochromatic system for use in bright daylight conditions, a two color system for darker ambients, or a full color system for use in night viewing conditions. Color imagery is achieved using field sequential video and a mechanical color wheel. In addition to the color symbology, high resolution computer-gene rated imagery from an onboard Silicon Graphics Reality Engine Onyx processor is available for research in virtual reality applications. This synthetic imagery can also be merged with real world video from a variety of imaging systems that can be installed easily on the front of the helicopter. These sensors include infrared or tv cameras, or potentially small millimeter wave radars. The Research Flight Control System is being developed for the aircraft by a team of contractors led by Boeing Helicopters. It consists of a full authority high bandwidth fly-by-wire actuators that drive the main rotor swashplate actuators and the tail rotor actuator in parallel. This arrangement allows the basic mechanical flight control system of the Black Hawk to be retained so that the safety pilot can monitor the operation of the system through the action of his own controls. The evaluation pilot will signal the fly

  8. Initial flight and simulator evaluation of a head up display for standard and noise abatement visual approaches

    NASA Technical Reports Server (NTRS)

    Bourquin, K.; Palmer, E. A.; Cooper, G.; Gerdes, R. M.

    1973-01-01

    A preliminary assessment was made of the adequacy of a simple head up display (HUD) for providing vertical guidance for flying noise abatement and standard visual approaches in a jet transport. The HUD featured gyro-stabilized approach angle scales which display the angle of declination to any point on the ground and a horizontal flight path bar which aids the pilot in his control of the aircraft flight path angle. Thirty-three standard and noise abatement approaches were flown in a Boeing 747 aircraft equipped with a head up display. The HUD was also simulated in a research simulator. The simulator was used to familiarize the pilots with the display and to determine the most suitable way to use the HUD for making high capture noise abatement approaches. Preliminary flight and simulator data are presented and problem areas that require further investigation are identified.

  9. A Three-Dimensional Heads-Up Primary Navigation Reference Display for Paratroopers Performing High Altitude High Open Jumps

    DTIC Science & Technology

    2007-11-02

    47 Figure 17. Basic Java3D Scene Graph [J3D99] .......................................................................................... 48...paratrooper’s movement in the physical world, measured by GPS, as movement in a computer generated scene . This reference, presented as a heads-up display on...the display with NVGs and the fact that the platform must be mobile enough to travel with a paratrooper both in an aircraft and under canopy. 1.3.2

  10. Chronic monitoring of cortical hemodynamics in behaving, freely-moving rats using a miniaturized head-mounted optical microscope

    NASA Astrophysics Data System (ADS)

    Sigal, Iliya; Gad, Raanan; Koletar, Margaret; Ringuette, Dene; Stefanovic, Bojana; Levi, Ofer

    2016-03-01

    Growing interest within the neurophysiology community in assessing healthy and pathological brain activity in animals that are awake and freely-behaving has triggered the need for optical systems that are suitable for such longitudinal studies. In this work we report label-free multi-modal imaging of cortical hemodynamics in the somatosensory cortex of awake, freely-behaving rats, using a novel head-mounted miniature optical microscope. The microscope employs vertical cavity surface emitting lasers (VCSELs) at three distinct wavelengths (680 nm, 795 nm, and 850 nm) to provide measurements of four hemodynamic markers: blood flow speeds, HbO, HbR, and total Hb concentration, across a > 2 mm field of view. Blood flow speeds are extracted using Laser Speckle Contrast Imaging (LSCI), while oxygenation measurements are performed using Intrinsic Optical Signal Imaging (IOSI). Longitudinal measurements on the same animal are made possible over the course of > 6 weeks using a chronic window that is surgically implanted into the skull. We use the device to examine changes in blood flow and blood oxygenation in superficial cortical blood vessels and tissue in response to drug-induced absence-like seizures, correlating motor behavior with changes in blood flow and blood oxygenation in the brain.

  11. Identification of Prey Captures in Australian Fur Seals (Arctocephalus pusillus doriferus) Using Head-Mounted Accelerometers: Field Validation with Animal-Borne Video Cameras

    PubMed Central

    Volpov, Beth L.; Hoskins, Andrew J.; Battaile, Brian C.; Viviant, Morgane; Wheatley, Kathryn E.; Marshall, Greg; Abernathy, Kyler; Arnould, John P. Y.

    2015-01-01

    This study investigated prey captures in free-ranging adult female Australian fur seals (Arctocephalus pusillus doriferus) using head-mounted 3-axis accelerometers and animal-borne video cameras. Acceleration data was used to identify individual attempted prey captures (APC), and video data were used to independently verify APC and prey types. Results demonstrated that head-mounted accelerometers could detect individual APC but were unable to distinguish among prey types (fish, cephalopod, stingray) or between successful captures and unsuccessful capture attempts. Mean detection rate (true positive rate) on individual animals in the testing subset ranged from 67-100%, and mean detection on the testing subset averaged across 4 animals ranged from 82-97%. Mean False positive (FP) rate ranged from 15-67% individually in the testing subset, and 26-59% averaged across 4 animals. Surge and sway had significantly greater detection rates, but also conversely greater FP rates compared to heave. Video data also indicated that some head movements recorded by the accelerometers were unrelated to APC and that a peak in acceleration variance did not always equate to an individual prey item. The results of the present study indicate that head-mounted accelerometers provide a complementary tool for investigating foraging behaviour in pinnipeds, but that detection and FP correction factors need to be applied for reliable field application. PMID:26107647

  12. Identification of Prey Captures in Australian Fur Seals (Arctocephalus pusillus doriferus) Using Head-Mounted Accelerometers: Field Validation with Animal-Borne Video Cameras.

    PubMed

    Volpov, Beth L; Hoskins, Andrew J; Battaile, Brian C; Viviant, Morgane; Wheatley, Kathryn E; Marshall, Greg; Abernathy, Kyler; Arnould, John P Y

    2015-01-01

    This study investigated prey captures in free-ranging adult female Australian fur seals (Arctocephalus pusillus doriferus) using head-mounted 3-axis accelerometers and animal-borne video cameras. Acceleration data was used to identify individual attempted prey captures (APC), and video data were used to independently verify APC and prey types. Results demonstrated that head-mounted accelerometers could detect individual APC but were unable to distinguish among prey types (fish, cephalopod, stingray) or between successful captures and unsuccessful capture attempts. Mean detection rate (true positive rate) on individual animals in the testing subset ranged from 67-100%, and mean detection on the testing subset averaged across 4 animals ranged from 82-97%. Mean False positive (FP) rate ranged from 15-67% individually in the testing subset, and 26-59% averaged across 4 animals. Surge and sway had significantly greater detection rates, but also conversely greater FP rates compared to heave. Video data also indicated that some head movements recorded by the accelerometers were unrelated to APC and that a peak in acceleration variance did not always equate to an individual prey item. The results of the present study indicate that head-mounted accelerometers provide a complementary tool for investigating foraging behaviour in pinnipeds, but that detection and FP correction factors need to be applied for reliable field application.

  13. Backup Alignment Devices on Shuttle: Heads-Up Display or Crew Optical Alignment Sight

    NASA Technical Reports Server (NTRS)

    Chavez, Melissa A.

    2011-01-01

    NASA s Space Shuttle was built to withstand multiple failures while still keeping the crew and vehicle safe. Although the design of the Space Shuttle had a great deal of redundancy built into each system, there were often additional ways to keep systems in the best configuration if a failure were to occur. One such method was to use select pieces of hardware in a way for which they were not primarily intended. The primary function of the Heads-Up Display (HUD) was to provide the crew with a display of flight critical information during the entry phase. The primary function of the Crew Optical Alignment Sight (COAS) was to provide the crew an optical alignment capability for rendezvous and docking phases. An alignment device was required to keep the Inertial Measurement Units (IMUs) well aligned for a safe Entry; nominally this alignment device would be the two on-board Star Trackers. However, in the event of a Star Tracker failure, the HUD or COAS could also be used as a backup alignment device, but only if the device had been calibrated beforehand. Once the HUD or COAS was calibrated and verified then it was considered an adequate backup to the Star Trackers for entry IMU alignment. There were procedures in place and the astronauts were trained on how to accurately calibrate the HUD or COAS and how to use them as an alignment device. The calibration procedure for the HUD and COAS had been performed on many Shuttle missions. Many of the first calibrations performed were for data gathering purposes to determine which device was more accurate as a backup alignment device, HUD or COAS. Once this was determined, the following missions would frequently calibrate the HUD in order to be one step closer to having the device ready in case it was needed as a backup alignment device.

  14. TRISTAR 1: Evaluation methods for testing head-up display (HUD) flight symbology

    NASA Technical Reports Server (NTRS)

    Newman, R. L.; Haworth, L. A.; Kessler, G. K.; Eksuzian, D. J.; Ercoline, W. R.; Evans, R. H.; Hughes, T. C.; Weinstein, L. F.

    1995-01-01

    The first in a series of piloted head-up display (HUD) flight symbology studies (TRISTAR) measuring pilot task performance was conducted at the NASA Ames Research Center by the Tri-Service Flight Symbology Working Group (FSWG). Sponsored by the U.S. Army Aeroflightdynamics Directorate, this study served as a focal point for the FSWG to examine HUD test methodology and flight symbology presentations. HUD climb-dive marker dynamics and climb-dive ladder presentations were examined as pilots performed air-to-air (A/A), air-to-ground (A/G), instrument landing system (ILS), and unusual attitude (UA) recover tasks. Symbolic presentations resembled pitch ladder variations used by the U.S. Air Force (USAF), U.S. Navy (USN), and Royal Air Force (RAF). The study was initiated by the FSWG to address HUD flight symbology deficiencies, standardization, issue identification, and test methodologies. It provided the mechanism by which the USAF, USN, RAF, and USA could integrate organizational ideas and reduce differences for comparisons. Specifically it examined flight symbology issues collectively identified by each organization and the use of objective and subjective text methodology and flight tasking proposed by the FSWG.

  15. Enhanced/Synthetic Vision and Head-Worn Display Technologies for Terminal Maneuvering Area NextGen Operations

    NASA Technical Reports Server (NTRS)

    Arthur, Jarvis J., III; Prinzell, Lawrence J.; Williams, Steven P.; Bailey, Randall E.; Shelton, Kevin J.; Norman, R. Mike

    2011-01-01

    NASA is researching innovative technologies for the Next Generation Air Transportation System (NextGen) to provide a "Better-Than-Visual" (BTV) capability as adjunct to "Equivalent Visual Operations" (EVO); that is, airport throughputs equivalent to that normally achieved during Visual Flight Rules (VFR) operations rates with equivalent and better safety in all weather and visibility conditions including Instrument Meteorological Conditions (IMC). These new technologies build on proven flight deck systems and leverage synthetic and enhanced vision systems. Two piloted simulation studies were conducted to access the use of a Head-Worn Display (HWD) with head tracking for synthetic and enhanced vision systems concepts. The first experiment evaluated the use a HWD for equivalent visual operations to San Francisco International Airport (airport identifier: KSFO) compared to a visual concept and a head-down display concept. A second experiment evaluated symbology variations under different visibility conditions using a HWD during taxi operations at Chicago O'Hare airport (airport identifier: KORD). Two experiments were conducted, one in a simulated San Francisco airport (KSFO) approach operation and the other, in simulated Chicago O'Hare surface operations, evaluating enhanced/synthetic vision and head-worn display technologies for NextGen operations. While flying a closely-spaced parallel approach to KSFO, pilots rated the HWD, under low-visibility conditions, equivalent to the out-the-window condition, under unlimited visibility, in terms of situational awareness (SA) and mental workload compared to a head-down enhanced vision system. There were no differences between the 3 display concepts in terms of traffic spacing and distance and the pilot decision-making to land or go-around. For the KORD experiment, the visibility condition was not a factor in pilot's rating of clutter effects from symbology. Several concepts for enhanced implementations of an unlimited field

  16. Enhanced/synthetic vision and head-worn display technologies for terminal maneuvering area NextGen operations

    NASA Astrophysics Data System (ADS)

    Arthur, Jarvis J., III; Prinzel, Lawrence J., III; Williams, Steven P.; Bailey, Randall E.; Shelton, Kevin J.; Norman, R. Mike

    2011-06-01

    NASA is researching innovative technologies for the Next Generation Air Transportation System (NextGen) to provide a "Better-Than-Visual" (BTV) capability as adjunct to "Equivalent Visual Operations" (EVO); that is, airport throughputs equivalent to that normally achieved during Visual Flight Rules (VFR) operations rates with equivalent and better safety in all weather and visibility conditions including Instrument Meteorological Conditions (IMC). These new technologies build on proven flight deck systems and leverage synthetic and enhanced vision systems. Two piloted simulation studies were conducted to access the use of a Head-Worn Display (HWD) with head tracking for synthetic and enhanced vision systems concepts. The first experiment evaluated the use a HWD for equivalent visual operations to San Francisco International Airport (airport identifier: KSFO) compared to a visual concept and a head-down display concept. A second experiment evaluated symbology variations under different visibility conditions using a HWD during taxi operations at Chicago O'Hare airport (airport identifier: KORD). Two experiments were conducted, one in a simulated San Francisco airport (KSFO) approach operation and the other, in simulated Chicago O'Hare surface operations, evaluating enhanced/synthetic vision and head-worn display technologies for NextGen operations. While flying a closely-spaced parallel approach to KSFO, pilots rated the HWD, under low-visibility conditions, equivalent to the out-the-window condition, under unlimited visibility, in terms of situational awareness (SA) and mental workload compared to a head-down enhanced vision system. There were no differences between the 3 display concepts in terms of traffic spacing and distance and the pilot decision-making to land or go-around. For the KORD experiment, the visibility condition was not a factor in pilot's rating of clutter effects from symbology. Several concepts for enhanced implementations of an unlimited field

  17. Leadership Behaviour Displayed by Heads of School--Its Extent and Importance

    ERIC Educational Resources Information Center

    Vilkinas, Tricia; West, Deborah

    2011-01-01

    This paper reports results of analyses of data from an online 360[degrees] feedback survey with 19 heads of school, 23 line managers and 120 significant others (peers, academic staff and administrative staff) from Australian universities. It focuses on the heads' effectiveness, and the extent and importance of several leadership roles. A series of…

  18. The effect of a monocular helmet-mounted display on aircrew health: a 10-year prospective cohort study of Apache AH MK 1 pilots: study midpoint update

    NASA Astrophysics Data System (ADS)

    Hiatt, Keith L.; Rash, Clarence E.; Watters, Raymond W.; Adams, Mark S.

    2009-05-01

    A collaborative occupational health study has been undertaken by Headquarters Army Aviation, Middle Wallop, UK, and the U.S. Army Aeromedical Research Laboratory, Fort Rucker, Alabama, to determine if the use of the Integrated Helmet and Display Sighting System (IHADSS) monocular helmet-mounted display (HMD) in the Apache AH Mk 1 attack helicopter has any long-term (10-year) effect on visual performance. The test methodology consists primarily of a detailed questionnaire and an annual battery of vision tests selected to capture changes in visual performance of Apache aviators over their flight career (with an emphasis on binocular visual function). Pilots using binocular night vision goggles serve as controls and undergo the same methodology. Currently, at the midpoint of the study, with the exception of a possible colour discrimination effect, there are no data indicating that the long-term use of the IHADSS monocular HMD results in negative effects on vision.

  19. Development of the C-17 Heads-Up Display (HUD) Container, CNU-676/E

    DTIC Science & Technology

    2006-01-27

    the container, mounting system or test item. There was no evidence of any contact on impact between the radome and the container walls or cover...leak technique was used to pressurize the container to a minimum test pressure of 10.34 kPa (1.5 psi). Maximum allowable leak rate is 0.34 kPa (0.05...hour. TEST CONCLUSIONS – No damage occurred during the above testing to either the container, mounting system , or test item. There was no evidence

  20. Head-up display (HUD) utility. II - Runway to HUD transitions monitoring eye focus and decision times

    NASA Technical Reports Server (NTRS)

    Weintraub, D. J.; Haines, R. F.; Randle, R. J.

    1985-01-01

    An experiment conducted using a head-up display (HUD) suggests that the demonstrated superiority of the HUD over a conventional instrument panel stems from its superior layout of information. A HUD display presents instrument-panel information to pilots in such a way that the symbols appear as a virtual image at optical infinity superimposed on the landscape. In the experiment conducted, the luminance of the display symbology and its angle subtended at the eye remained fixed, while optical distance and gaze angle were varied. Concomitant measures of eye movements, eye accommodative state, and decision-making time concerning airspeed, altitude and runway condition were obtained. It is found that, while looking straight ahead, at zero diopters, the HUD shortens decision time by 80 to 90 msec, not statistically significant at the 0.05 (slope of diopter/gaze interaction) level. The question of a cognitive overload induced by the luminous symbols of the HUD is subsequently addressed.

  1. A Low-Cost Part-Task Flight Training System: An Application of a Head Mounted Display

    DTIC Science & Technology

    1990-12-01

    tasks. For example, landing an aircraft, take- off , and formation flying all require a set of loosely related tasks that are required flying skills. These...location; surround sound to let a virtual world user hear sound from the direction of generation (for example, if a pilot’s wingman off his left wing...different view, like off the left wing, the user just looks left. Rather than pressing ’t’ (for throttle) to increase power, a throttle is used; and rather

  2. Vertical Vergence Calibration for Augmented Reality Displays

    DTIC Science & Technology

    2006-03-01

    2006 2. REPORT TYPE 3. DATES COVERED 00-00-2006 to 00-00-2006 4. TITLE AND SUBTITLE Vertical Vergence Calibration for Augmented Reality Displays...8-98) Prescribed by ANSI Std Z39-18 Vertical Vergence Calibration for Augmented Reality Displays Mark A. Livingston∗ Adam Lederer Virtual Reality...dimensional Graphics and Realism—Virtual Reality Keywords: augmented reality , head-mounted display, vergence 1 INTRODUCTION Many augmented reality (AR

  3. Astrocytes in the Optic Nerve Head of Glaucomatous Mice Display a Characteristic Reactive Phenotype

    PubMed Central

    Wang, Rui; Seifert, Philip; Jakobs, Tatjana C.

    2017-01-01

    Purpose Optic nerve head astrocytes, a subtype of white-matter astrocytes, become reactive early in the course of glaucoma. It was shown recently that in the DBA/2J mouse model of inherited glaucoma optic nerve astrocytes extend new longitudinal processes into the axon bundles before ganglion cell loss becomes apparent. The present study aims at testing whether this behavior of astrocytes is typical of early glaucomatous damage. Methods Mice expressing green fluorescent protein in individual astrocytes were used to evaluate the early response of astrocytes in the glial lamina of the optic nerve head after increasing the IOP using the microbead occlusion method. Tissue sections from the glial lamina were imaged consecutively by confocal and electron microscopy. Results Confocal and electron microscope images show that astrocytes close to the myelination transition zone in the hypertensive nerve heads extend new processes that follow the longitudinal axis of the optic nerve and invade axon bundles in the nerve head. Ultrastructurally, the longitudinal processes were largely devoid of subcellular organelles except for degenerating mitochondria. Conclusions The longitudinal processes are a common feature of glaucomatous optic nerve astrocytes, whereas they are not observed after traumatic nerve injury. Thus, astrocytes appear to fine-tune their responses to the nature and/or timing of the injury to the neurons that they surround. PMID:28170536

  4. An Operational evaluation of head up displays for civil transport operations. NASA/FAA phase 3 report

    NASA Technical Reports Server (NTRS)

    Lauber, J. K.; Bray, R. S.; Harrison, R. L.; Hemingway, J. C.; Scott, B. C.

    1982-01-01

    The advantages and disadvantages of head-up displays (HUDs) in commercial jet transport approach and landing operations was evaluated. Ten airline captains currently qualified in the B-727 aircraft flew a series of instrument landing system (ILS) and nonprecision approaches in a motion base simulator using both a flight director HUD concept and a flightpath HUD concept as well as conventional head-down instruments under a variety of environmental and operational conditions to assess: (1) the potential benefits of these HUDs in airline operations; (2) problems which might be associated with their use; and (3) flight crew training requirements and flight crew operating procedures suitable for use with the HUDs. Results are presented in terms of objective simulator based performance measures, subject pilot opinion and rating data, and observer data.

  5. Cross-axis adaptation improves 3D vestibulo-ocular reflex alignment during chronic stimulation via a head-mounted multichannel vestibular prosthesis

    PubMed Central

    Dai, Chenkai; Fridman, Gene Y.; Chiang, Bryce; Davidovics, Natan; Melvin, Thuy-Anh; Cullen, Kathleen E.; Della Santina, Charles C.

    2012-01-01

    By sensing three-dimensional (3D) head rotation and electrically stimulating the three ampullary branches of a vestibular nerve to encode head angular velocity, a multichannel vestibular prosthesis (MVP) can restore vestibular sensation to individuals disabled by loss of vestibular hair cell function. However, current spread to afferent fibers innervating non-targeted canals and otolith endorgans can distort the vestibular nerve activation pattern, causing misalignment between the perceived and actual axis of head rotation. We hypothesized that over time, central neural mechanisms can adapt to correct this misalignment. To test this, we rendered five chinchillas vestibular-deficient via bilateral gentamicin treatment and unilaterally implanted them with a head mounted MVP. Comparison of 3D angular vestibulo-ocular reflex (aVOR) responses during 2 Hz, 50°/s peak horizontal sinusoidal head rotations in darkness on the first, third and seventh days of continual MVP use revealed that eye responses about the intended axis remained stable (at about 70% of the normal gain) while misalignment improved significantly by the end of one week of prosthetic stimulation. A comparable time course of improvement was also observed for head rotations about the other two semicircular canal axes and at every stimulus frequency examined (0.2–5 Hz). In addition, the extent of disconjugacy between the two eyes progressively improved during the same time window. These results indicate that the central nervous system rapidly adapts to multichannel prosthetic vestibular stimulation to markedly improve 3D aVOR alignment within the first week after activation. Similar adaptive improvements are likely to occur in other species, including humans. PMID:21374081

  6. Simulation and flight test evaluation of head-up-display guidance for harrier approach transitions

    NASA Technical Reports Server (NTRS)

    Dorr, D. W.; Moralez, E., III; Merrick, V. K.

    1994-01-01

    Position and speed guidance displays for STOVL aircraft curved, decelerating approaches to hover and vertical landing have been evaluated for their effectiveness in reducing pilot workload and improving performance. The NASA V/STOL Systems Research Aircraft, a modified YAV-8B Harrier prototype, was used to evaluate the displays in flight, whereas the NASA Ames Vertical Motion Simulator was used to extend the flight test results to instrument meteorological conditions (IMC) and to examine performance in various conditions of wind and turbulence. The simulation data showed close correlation with the flight test data, and both demonstrated the feasibility of the displays. With the exception of the hover task in zero visibility, which was level-3, averaged Copper-Harper handling qualities ratings given during simulation were level-2 for both the approach task and the hover task in all conditions. During flight tests in calm and clear conditions, the displays also gave rise to level-2 handling qualities ratings. Pilot opinion showed that the guidance displays would be useful in visual flight, especially at night, as well as in IMC.

  7. Microscope-integrated intraoperative OCT with electrically tunable focus and heads-up display for imaging of ophthalmic surgical maneuvers.

    PubMed

    Tao, Yuankai K; Srivastava, Sunil K; Ehlers, Justis P

    2014-06-01

    We present novel optical and mechanical designs for a microscope-integrated intraoperative optical coherence tomography (iOCT) system with enhanced function and ergonomics for visualization of ophthalmic surgical maneuvers. Integration of an electrically tunable lens allows rapid focal plane adjustment and iOCT imaging of both anterior and posterior segment tissue microstructures while maintaining parfocality with the ophthalmic surgical microscope. We demonstrate novel visualization of instrument positions relative to tissue layers of interest as colormap overlays onto en face OCT data, which may provide integrative display of volumetric information during surgical maneuvers. Finally, we implement a heads-up display system to provide real-time feedback as proof-of-principle for iOCT-guided ophthalmic surgery.

  8. Quantification of Contrast Sensitivity and Color Perception using Head-worn Augmented Reality Displays

    DTIC Science & Technology

    2009-03-01

    the case the Sony Glasstron PLM -50, enables a filter that reduces transmittance of light from the environment. Two binocular displays showed differ...Edition). Thomson Wadsworth, 2007. [5] S. E. Kirkley, Jr. Augmented Reality Performance Assessment Bat- tery (ARPAB): Object Recognition, Distance

  9. Globular Head-Displayed Conserved Influenza H1 Hemagglutinin Stalk Epitopes Confer Protection against Heterologous H1N1 Virus

    PubMed Central

    Klausberger, Miriam; Tscheliessnig, Rupert; Neff, Silke; Nachbagauer, Raffael; Wohlbold, Teddy John; Wilde, Monika; Palmberger, Dieter; Krammer, Florian; Jungbauer, Alois; Grabherr, Reingard

    2016-01-01

    Significant genetic variability in the head region of the influenza A hemagglutinin, the main target of current vaccines, makes it challenging to develop a long-lived seasonal influenza prophylaxis. Vaccines based on the conserved hemagglutinin stalk domain might provide broader cross-reactive immunity. However, this region of the hemagglutinin is immunosubdominant to the head region. Peptide-based vaccines have gained much interest as they allow the immune system to focus on relevant but less immunogenic epitopes. We developed a novel influenza A hemagglutinin-based display platform for H1 hemagglutinin stalk peptides that we identified in an epitope mapping assay using human immune sera and synthetic HA peptides. Flow cytometry and competition assays suggest that the identified stalk sequences do not recapitulate the epitopes of already described broadly neutralizing stalk antibodies. Vaccine constructs displaying 25-mer stalk sequences provided up to 75% protection from lethal heterologous virus challenge in BALB/c mice and induced antibody responses against the H1 hemagglutinin. The developed platform based on a vaccine antigen has the potential to be either used as stand-alone or as prime-vaccine in combination with conventional seasonal or pandemic vaccines for the amplification of stalk-based cross-reactive immunity in humans or as platform to evaluate the relevance of viral peptides/epitopes for protection against influenza virus infection. PMID:27088239

  10. Navigational Heads-Up Display: Will a Shipboard Augmented Electronic Navigation System Sink or Swim?

    DTIC Science & Technology

    2015-03-01

    testbed platform consisted of a virtual environment that fully simulated a conning officer’ s basic tasks in conditions of restricted navigation; this...of a working display platform onboard Navy warships 14. SUBJECT TERl"\\IS Conning, virtual reality, augmented reality, cognitive tunneling, ship 15...testbed platform consisted of a virtual environment that fully simulated a conning officer’s basic tasks in conditions of restricted navigation; this type

  11. Optoelectronic Mounting Structure

    DOEpatents

    Anderson, Gene R.; Armendariz, Marcelino G.; Baca, Johnny R. F.; Bryan, Robert P.; Carson, Richard F.; Chu, Dahwey; Duckett, III, Edwin B.; McCormick, Frederick B.; Peterson, David W.; Peterson, Gary D.; Reber, Cathleen A.; Reysen, Bill H.

    2004-10-05

    An optoelectronic mounting structure is provided that may be used in conjunction with an optical transmitter, receiver or transceiver module. The mounting structure may be a flexible printed circuit board. Thermal vias or heat pipes in the head region may transmit heat from the mounting structure to the heat spreader. The heat spreader may provide mechanical rigidity or stiffness to the heat region. In another embodiment, an electrical contact and ground plane may pass along a surface of the head region so as to provide an electrical contact path to the optoelectronic devices and limit electromagnetic interference. In yet another embodiment, a window may be formed in the head region of the mounting structure so as to provide access to the heat spreader. Optoelectronic devices may be adapted to the heat spreader in such a manner that the devices are accessible through the window in the mounting structure.

  12. Documentation and teaching of surgery with an eye movement driven head-mounted camera: see what the surgeon sees and does.

    PubMed

    Schneider, Erich; Bartl, Klaus; Dera, Thomas; Böning, Guido; Wagner, Philipp; Brandt, Thomas

    2006-01-01

    A first proof of concept was developed for a head-mounted video camera system that is continuously aligned with the user's orientation of gaze. In doing so, it records images from the user's perspective that can document manual tasks during, e.g., surgery. Eye movements are tracked by video-oculography and used as signals to drive servo motors that rotate the camera. Thus, the sensorimotor output of a biological system for the control of eye movements evolved over millions of years is used to move an artificial eye. All the capabilities of multi-sensory processing for eye, head, and surround motions are detected by the vestibular, visual, and somatosensory systems and used to drive a technical camera system. A camera guided in this way mimics the natural exploration of a visual scene and acquires video sequences from the perspective of a mobile user, while the oculomotor reflexes naturally stabilize the camera on target during head and target movements. Various documentation and teaching applications in health care, industry, and research are conceivable.

  13. Advanced helmet mounted display (AHMD)

    NASA Astrophysics Data System (ADS)

    Sisodia, Ashok; Bayer, Michael; Townley-Smith, Paul; Nash, Brian; Little, Jay; Cassarly, William; Gupta, Anurag

    2007-04-01

    Due to significantly increased U.S. military involvement in deterrent, observer, security, peacekeeping and combat roles around the world, the military expects significant future growth in the demand for deployable virtual reality trainers with networked simulation capability of the battle space visualization process. The use of HMD technology in simulated virtual environments has been initiated by the demand for more effective training tools. The AHMD overlays computer-generated data (symbology, synthetic imagery, enhanced imagery) augmented with actual and simulated visible environment. The AHMD can be used to support deployable reconfigurable training solutions as well as traditional simulation requirements, UAV augmented reality, air traffic control and Command, Control, Communications, Computers, Intelligence, Surveillance, and Reconnaissance (C4ISR) applications. This paper will describe the design improvements implemented for production of the AHMD System.

  14. Conformal flight path symbology for head-up displays: Defining the distribution of visual attention in three-dimensional space

    NASA Astrophysics Data System (ADS)

    Ververs, Patricia May

    An extensive investigation of the format for head-up display (HUD) instrumentation was conducted in a two-part experiment. First, a pilot's information requirements for the tasks of approach, landing, and taxi were determined through a survey administered to professional commercial pilots via the world wide web. The results of the survey were applied in the development of two symbology sets, one set for flight navigation and the second for ground navigation. Second, twenty pilots from the University of Illinois at Urbana-Champaign were recruited to participate in a 3-day experiment. The study was designed to investigate the format for symbology on HUDs and the performance effects of using conformal and partially conformal symbology to support the pilots' tasks. In addition, two different methods were investigated for supporting the pilots' transition between the task of flying and the task of landing. A seamless transition used visual momentum techniques to smoothly guide the pilots' cognitive transition between the serial displays and the associated tasks. A seamed approach employed an abrupt change between the displays to alert the pilots of the task switch. The results indicate that incorporating a virtually conformal, tunnel-in-the-sky symbology into a complete HUD instrumentation set offers promising pilot performance effects. Pilots easily navigated the complex curved approaches with little to no deviation from the flight path (approximately 10 feet), while performing the secondary tasks of the scanning their instruments and the environment. The seamless transition between the flight and ground symbology offered the pilots a preview of the upcoming landing task, thereby preparing them for the task switch. On the ground, the perspective (scene-linked) symbology set supported landing and taxi navigation tasks with the equal efficiency to the plan view display but with much greater precision. Theories of allocation of attention were used to interpret the

  15. Color speckle in laser displays

    NASA Astrophysics Data System (ADS)

    Kuroda, Kazuo

    2015-07-01

    At the beginning of this century, lighting technology has been shifted from discharge lamps, fluorescent lamps and electric bulbs to solid-state lighting. Current solid-state lighting is based on the light emitting diodes (LED) technology, but the laser lighting technology is developing rapidly, such as, laser cinema projectors, laser TVs, laser head-up displays, laser head mounted displays, and laser headlamps for motor vehicles. One of the main issues of laser displays is the reduction of speckle noise1). For the monochromatic laser light, speckle is random interference pattern on the image plane (retina for human observer). For laser displays, RGB (red-green-blue) lasers form speckle patterns independently, which results in random distribution of chromaticity, called color speckle2).

  16. Design and Testing of an Unlimited Field-of-regard Synthetic Vision Head-worn Display for Commercial Aircraft Surface Operations

    NASA Technical Reports Server (NTRS)

    Arthur, Jarvis J., III; Prinzel, Lawrence J., III; Shelton, Kevin J.; Kramer, Lynda J.; Williams, Steven P.; Bailey, Randall E.; Norman, Robert M.

    2007-01-01

    Experiments and flight tests have shown that a Head-Up Display (HUD) and a head-down, electronic moving map (EMM) can be enhanced with Synthetic Vision for airport surface operations. While great success in ground operations was demonstrated with a HUD, the research noted that two major HUD limitations during ground operations were their monochrome form and limited, fixed field of regard. A potential solution to these limitations found with HUDs may be emerging Head Worn Displays (HWDs). HWDs are small, lightweight full color display devices that may be worn without significant encumbrance to the user. By coupling the HWD with a head tracker, unlimited field-of-regard may be realized for commercial aviation applications. In the proposed paper, the results of two ground simulation experiments conducted at NASA Langley are summarized. The experiments evaluated the efficacy of head-worn display applications of Synthetic Vision and Enhanced Vision technology to enhance transport aircraft surface operations. The two studies tested a combined six display concepts: (1) paper charts with existing cockpit displays, (2) baseline consisting of existing cockpit displays including a Class III electronic flight bag display of the airport surface; (3) an advanced baseline that also included displayed traffic and routing information, (4) a modified version of a HUD and EMM display demonstrated in previous research; (5) an unlimited field-of-regard, full color, head-tracked HWD with a conformal 3-D synthetic vision surface view; and (6) a fully integrated HWD concept. The fully integrated HWD concept is a head-tracked, color, unlimited field-of-regard concept that provides a 3-D conformal synthetic view of the airport surface integrated with advanced taxi route clearance, taxi precision guidance, and data-link capability. The results of the experiments showed that the fully integrated HWD provided greater path performance compared to using paper charts alone. Further, when

  17. Head mounted DLP for visual stimulation in freely moving rats: a novel tool for visual neuroscience research

    NASA Astrophysics Data System (ADS)

    Mandel, Yossi; Arens-Arad, Tamar; Farah, Nairouz; Zlotnik, Alex; Zalevsky, Zeev

    2015-03-01

    Novel technologies are constantly under development for vision restoration in blind patients. In some of these techniques, such as photodiode implants or optogenetics based treatment, a glasses mounted optical projection system projects the visual scene onto the retina. The desired projection system is characterized by a relatively high power density, a localized retinal stimulation area and compatibility for wavelengths that are specific for the technology at hand. The challenges of obtaining such a projection system are not only limited by developing the tools and the apparatus for testing the visual performance of artificial retina, but also devising the technique and the methodology for training and testing the behaving animals using this tool. Current research techniques used for evaluation of visual function in behaving animals utilize computer screens for retinal stimulation, and therefore do not fulfill the requirements of the evaluation of retinal implant performance or optogenetics based treatment (inefficient power and no wavelength flexibility). In the following work we will present and evaluate a novel projection system that is suited for behavioral animal studies and meet the requirements for artificial retinal stimulation. The proposed system is based on a miniature Digital Mirror Device (DMD) for pattern projection and a telescope for relaying the pattern directly onto the animal eye. This system facilitates the projection of patterns with high spatial resolution at high light intensities with the desired wavelength and may prove to be a vital tool in natural and artificial vision performance research in behaving animals.

  18. Head orientation prediction: delta quaternions versus quaternions.

    PubMed

    Himberg, Henry; Motai, Yuichi

    2009-12-01

    Display lag in simulation environments with helmet-mounted displays causes a loss of immersion that degrades the value of virtual/augmented reality training simulators. Simulators use predictive tracking to compensate for display lag, preparing display updates based on the anticipated head motion. This paper proposes a new method for predicting head orientation using a delta quaternion (DQ)-based extended Kalman filter (EKF) and compares the performance to a quaternion EKF. The proposed framework operates on the change in quaternion between consecutive data frames (the DQ), which avoids the heavy computational burden of the quaternion motion equation. Head velocity is estimated from the DQ by an EKF and then used to predict future head orientation. We have tested the new framework with captured head motion data and compared it with the computationally expensive quaternion filter. Experimental results indicate that the proposed DQ method provides the accuracy of the quaternion method without the heavy computational burden.

  19. A novel detachable head-mounted device for simultaneous EEG and photoacoustic monitoring of epilepsy in freely moving rats.

    PubMed

    Wang, Bo; Zhou, Junli; Carney, Paul; Jiang, Huabei

    2015-02-01

    The study of neuro-hemodynamic changes in freely moving animals provides for a better understanding of brain dynamics in normal and disease states. While it has been shown that hemodynamic changes are closely related to seizures, methods for detection in freely moving animals are limited. In this work, we integrate photoacoustic sensor technology and electroencephalography into a small portable device that can be attached on the head of wake freely moving animals. We demonstrate chronic simultaneous monitoring of photoacoustic and electroencephalographic signals in an acute seizure model of epilepsy. Our results demonstrate that both the neural and vascular responses during seizures in freely moving rats have characteristics which are observed to be different and more diverse from that of anesthetized rats. This implies that the neurovascular coupling in seizure in free moving animals are more complicated, which calls for more detailed study in future. To the best of our knowledge, this is the first time for hemodynamic monitoring of seizure in free moving animals. This technology also promises for other hemodynamic related research study in freely moving small animals.

  20. Evaluation of Microscopic Disease in Oral Tongue Cancer Using Whole-Mount Histopathologic Techniques: Implications for the Management of Head-and-Neck Cancers

    SciTech Connect

    Campbell, Sorcha; Poon, Ian; Markel, Dan; Vena, Dan; Higgins, Kevin; Enepekides, Dan; Rapheal, Simon; Wong, John; Allo, Ghassan; Morgen, Eric; Khaoum, Nader; Smith, Ben; Balogh, Judith; MacKenzie, Robert; Davidson, Jean; Wang, Dan; Yaffe, Martin

    2012-02-01

    Purpose: To map the distribution of microscopic disease (MD) in head-and-neck cancer by analyzing digital images of whole-mounted serial sections of tongue cancer specimens. Methods and Materials: Ten T1-3 oral tongue cancer specimens were evaluated. The specimens were sliced into 3-mm blocks from which one or more 4-{mu}m slides were taken and digitized to create whole-mounted serial sections. Gross tumor and microscopic disease were digitally contoured on each slide. Lines perpendicular to the gross tumor volume (GTV) edge were created at 0.05-mm intervals and the distance between GTV and MD measured. Results: Of 88 slides assessed, 44 (50%) had evidence of MD. Of the 63,809 perpendicular lines drawn along the GTV edges, 2320 (3.6%) encountered microscopic disease along their path. The majority of MD abutted the GTV, and only 26.7% was noncontiguous with the GTV edge. The maximum distance from the border was 7.8 mm. Ninety-nine percent of all MD was within 4.75 mm and 95% was within 3.95 mm of the GTV. Conclusion: In this study we were able to assess the distribution of MD more accurately than has been possible with routine pathologic techniques. The results indicate that when the GTV is correctly identified, there is very little MD to be found outside this volume. This has implications for the volume of tissue resected at surgery and the volume included in the clinical target volume in conformal radiotherapy planning.

  1. 76 FR 17582 - Special Conditions: Bombardier Model BD-700-1A10 and BD-700-1A11 Airplanes, Head-Up Display (HUD...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-03-30

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF TRANSPORTATION Federal Aviation Administration 14 CFR Part 25 Special Conditions: Bombardier Model BD-700-1A10 and BD-700-1A11 Airplanes, Head-Up Display (HUD) With Video Synthetic Vision System (SVS) AGENCY: Federal...

  2. The effect of helmet-mounted display symbology on the opto-kinetic cervical reflex, frame of reference, and pilot performance

    NASA Astrophysics Data System (ADS)

    Liggett, Kristen Kim

    2000-08-01

    In spite of all the latest technological advances incorporated into today's modern fighter aircraft, spatial disorientation (SD) in flight continues to be a problem. To determine their attitude, pilots need a frame of reference against which their orientation can be compared. Recently, there have been numerous studies conducted that verify and characterize a visual reflex observed in pilots called the opto-kinetic cervical reflex (OKCR), which implies that pilots use a world frame of reference to orient themselves when looking at real world visual cues. In contrast, when pilots use instruments to determine orientation, the information is portrayed in an aircraft frame of reference. Transitions between the two frames of reference appear to be related to SD incidences. New helmet-mounted display (HMD) technology is being designed for the cockpit. HMDs portray aircraft-referenced symbology superimposed on a world-referenced scene. This research was designed to investigate how pilots would use real world and symbology frames of reference under various task configurations. Because the HMD horizon symbol is conformal to the true horizon, it was hypothesized that pilots would exhibit the OKCR, when viewing the real-world horizon cue with the HMD horizon symbol as in visual meteorological conditions (VMC) and when viewing the horizon symbology alone during instrument meteorological conditions (IMC). It was also hypothesized that transitions between different visual cues would be easier for the pilot to achieve when using the HMD. Twelve pilot-subjects completed four tasks (VMC flight, IMC flight, unusual attitude recovery, and in and out of clouds) to examine frames of reference and pilot performance. Results showed that pilots did not exhibit the OKCR when using the HMD symbology during the VMC and IMC tasks, indicating that a world frame of reference was not used to perform the tasks. In tasks where both real world visuals and the HMD symbology were present, pilots were

  3. Optical advantages in retinal scanning displays

    NASA Astrophysics Data System (ADS)

    Urey, Hakan

    2000-06-01

    Virtual Retinal DisplayTM technology is a retinal scanning display (RSD) technology being developed at Microvision, Inc., for a variety of applications including microdisplays. An RSD scans a modulated light beam onto a viewer's retina to produce a perceived image. Red, green and blue light sources, such as lasers, laser diodes or LEDs combine with Microvision's proprietary miniaturized scanner designs to make the RSD very well suited for head-worn and helmet-mounted displays (HMD). This paper compares the features of RSD technology to other display technologies such as the cathode ray tubes or matrix-based displays for HMD and other wearable display applications, and notes important performance advantages due to the number of pixel- generating elements. Also discussed are some fundamental optical limitations for virtual displays used in the HMD applications.

  4. Plasma Screen Floating Mount

    DOEpatents

    Eakle, Robert F.; Pak, Donald J.

    2004-10-26

    A mounting system for a flat display screen, particularly a plasma display screen, suspends the screen separately in each of the x-, y- and z-directions. A series of frames located by linear bearings and isolated by springs and dampers allows separate controlled movement in each axis. The system enables the use of relatively larger display screens in vehicles in which plasma screen are subject to damage from vibration.

  5. Effects of Head-Supported Devices on Female Aviators during Simulated Helicopter Missions

    DTIC Science & Technology

    1998-05-01

    addressed. 14. SUBJECT TERMS . , . . Helmets, Head-mounted displays, Head-supported devices, Night-vision goggles, Whole-body vibration , helicopter ...Training Phase 1" Simulated Helicopter Vibration 16 Subject Preparation 17 Maximum Voluntary Contraction and EMG Calibration 17 Sub-maximal Endurance 17...exposure of female military subjects to simulated helicopter vibration signatures and different helmet configurations. Ultimately, these limits must

  6. Combustor mount

    SciTech Connect

    Harris, H.S.

    1986-07-01

    For a gas turbine engine, mounting means are described for attaching the annular burner to the engine case including a mount lug having a relatively flat surface extending from and secured to the annular burner, a mount pin attached to the engine case having one end extending through an opening in the flat surface of the mount lug, a bushing frictionally engaging the pin and extending through the opening, and having a flange surrounding the opening and bearing against one side of the flat surface, a washer fitted over the pin and bearing against the opposite side of the flat surface to sandwich with the flange the mount lug, and the bushing having an increased internal diameter portion adjacent the washer and weldment means securing the washer to the mount lug.

  7. New ultraportable display technology and applications

    NASA Astrophysics Data System (ADS)

    Alvelda, Phillip; Lewis, Nancy D.

    1998-08-01

    MicroDisplay devices are based on a combination of technologies rooted in the extreme integration capability of conventionally fabricated CMOS active-matrix liquid crystal display substrates. Customized diffraction grating and optical distortion correction technology for lens-system compensation allow the elimination of many lenses and systems-level components. The MicroDisplay Corporation's miniature integrated information display technology is rapidly leading to many new defense and commercial applications. There are no moving parts in MicroDisplay substrates, and the fabrication of the color generating gratings, already part of the CMOS circuit fabrication process, is effectively cost and manufacturing process-free. The entire suite of the MicroDisplay Corporation's technologies was devised to create a line of application- specific integrated circuit single-chip display systems with integrated computing, memory, and communication circuitry. Next-generation portable communication, computer, and consumer electronic devices such as truly portable monitor and TV projectors, eyeglass and head mounted displays, pagers and Personal Communication Services hand-sets, and wristwatch-mounted video phones are among the may target commercial markets for MicroDisplay technology. Defense applications range from Maintenance and Repair support, to night-vision systems, to portable projectors for mobile command and control centers.

  8. Optics designs and system MTF for laser scanning displays

    NASA Astrophysics Data System (ADS)

    Urey, Hakan; Nestorovic, Ned; Ng, Baldwin S.; Gross, Abraham A.

    1999-07-01

    The Virtual Retinal DisplayTM (VRDTM) technology is a new display technology being developed at Microvision Inc. The displayed image is scanned onto the viewer's retina using low- power red, green, and blue light sources. Microvision's proprietary miniaturized scanner designs make VRD system very well suited for head-mounted displays. In this paper we discuss some of the advantages of the VRD technology, various ocular designs for HMD and other applications, and details of constructing a system MTF budget for laser scanning systems that includes electronics, modulators, scanners, and optics.

  9. Design of monocular multiview stereoscopic 3D display

    NASA Astrophysics Data System (ADS)

    Sakamoto, Kunio; Saruta, Kazuki; Takeda, Kazutoki

    2001-06-01

    A 3D head mounted display (HMD) system is useful for constructing a virtual space. The authors have developed a 3D HMD system using the monocular stereoscopic display. This paper shows that the 3D vision system using the monocular stereoscopic display and capturing camera builds a 3D virtual space for a telemanipulation using a captured real 3D image. In this paper, we propose the monocular stereoscopic 3D display and capturing camera for a tele- manipulation system. In addition, we describe the result of depth estimation using the multi-focus retinal images.

  10. The role of cognitive switching in head-up displays. [to determine pilot ability to accurately extract information from either of two sources

    NASA Technical Reports Server (NTRS)

    Fischer, E.

    1979-01-01

    The pilot's ability to accurately extract information from either one or both of two superimposed sources of information was determined. Static, aerial, color 35 mm slides of external runway environments and slides of corresponding static head-up display (HUD) symbology were used as the sources. A three channel tachistoscope was utilized to show either the HUD alone, the scene alone, or the two slides superimposed. Cognitive performance of the pilots was assessed by determining the percentage of correct answers given to two HUD related questions, two scene related questions, or one HUD and one scene related question.

  11. A review of some head-up display formats. [tests on sensing equipment for flights following partly visible terrain close to the ground

    NASA Technical Reports Server (NTRS)

    Naish, J. M.

    1979-01-01

    Two alternate head-up display devices (HUD) were compared for properties relevant to the accurate performance of concurrent tasks in real flight conditions and in various flight modes. The comparisons were made to find the disorientation resistance of the HUDs along with the tracking accuracy, interference resistance, fixation resistance, and error resistance. The use of displacement and flight path information for vertical control is discussed in terms of flight stability. Several combinations of symbols and driving signals are described, including a compensated control law, which were used in simulated flight to deal with wind shear.

  12. Wavelength-Dependent and-Independent Effects of Veiling Glare on the Visibility of Head-Up Display (HUD) Symbology

    DTIC Science & Technology

    1988-09-01

    the wavelength dependence of human illuminance sensitivity. When the human visibility function is taken into account, the magnitude of the wavelength... dependence is reduced by a factor of 4.2. A second effect is a wavelength-independent effect in subjects. This second effect is directly correlated with...displays; Illuminance; Laser bioeffects; Visibility; Visual perception; Visual sensitivity; Wavelength dependence .

  13. A heads-up display for diabetic limb salvage surgery: a view through the google looking glass.

    PubMed

    Armstrong, David G; Rankin, Timothy M; Giovinco, Nicholas A; Mills, Joseph L; Matsuoka, Yoky

    2014-09-01

    Although the use of augmented reality has been well described over the past several years, available devices suffer from high cost, an uncomfortable form factor, suboptimal battery life, and lack an app-based developer ecosystem. This article describes the potential use of a novel, consumer-based, wearable device to assist surgeons in real time during limb preservation surgery and clinical consultation. Using routine intraoperative, clinical, and educational case examples, we describe the use of a wearable augmented reality device (Google Glass; Google, Mountain View, CA). The device facilitated hands-free, rapid communication, documentation, and consultation. An eyeglass-mounted screen form factor has the potential to improve communication, safety, and efficiency of intraoperative and clinical care. We believe this represents a natural progression toward union of medical devices with consumer technology.

  14. Pressure vessel bottle mount

    NASA Technical Reports Server (NTRS)

    Wingett, Paul (Inventor)

    2001-01-01

    A mounting assembly for mounting a composite pressure vessel to a vehicle includes a saddle having a curved surface extending between two pillars for receiving the vessel. The saddle also has flanged portions which can be bolted to the vehicle. Each of the pillars has hole in which is mounted the shaft portion of an attachment member. A resilient member is disposed between each of the shaft portions and the holes and loaded by a tightening nut. External to the holes, each of the attachment members has a head portion to which a steel band is attached. The steel band circumscribes the vessel and translates the load on the springs into a clamping force on the vessel. As the vessel expands and contracts, the resilient members expand and contract so that the clamping force applied by the band to the vessel remains constant.

  15. Proliferation of counterbalanced, CRT-based stereoscopic displays for virtual environment viewing and control

    NASA Astrophysics Data System (ADS)

    Bolas, Mark T.; Lorimer, Eric R.; McDowall, Ian E.; Mead, R. X.

    1994-04-01

    Many researchers have felt that counterbalanced, stereoscopic immersive displays were an interim technology that would be supplanted as advances in LCDs and electronics made lightweight, head-mounted viewers popular. While there is still a long way to go in the development of truly practical head-mounted displays, it now seems clear that counterbalanced display will always play a significant role in the development, applications, and general dissemination of virtual environment tools. This paper hopes to explain the unexpected popularity of these devices, and to highlight features of these displays that have become apparent since the 1989 SPIE paper that described an early workable example of this genre. In addition, this paper describes the current state of this technology and the acceptance of counterbalanced displays in a wide range of applications since the original SPIE paper.

  16. Mirror mount

    DOEpatents

    Humpal, Harold H.

    1987-01-01

    A mirror mount (10) is provided that allows free pitch, yaw and roll motion of the mirror (28) while keeping the location of a point (56) on the surface of the mirror (28) fixed in the rest frame of reference of the mount (10). Yaw movement is provided by two yaw cylinders (30,32) that are bearing (52) mounted to provide rotation. Pitch and roll motion is provided by a spherically annular shell (42) that is air bearing (72,74) mounted to move between a clamp (60) and an upper pedestal bearing (44). The centers of curvature of the spherical surfaces of the shell (42) lie upon the point (56). Pitch motion and roll motion are separately and independently imparted to mirror (28) by a pair of pitch paddles (34) and a pair of roll paddles (36) that are independently and separately moved by control rods (76,80) driven by motors (78,82).

  17. Mirror mount

    DOEpatents

    Humpal, H.H.

    1986-03-21

    A mirror mount is provided that allows free pitch, yaw and roll motion of the mirror while keeping the location of a point on the surface of the mirror fixed in the rest frame of reference of the mount. Yaw movement is provided by two yaw cylinders that are bearing mounted to provide rotation. Pitch and roll motion is provided by a spherically annular shell that is air bearing mounted to move between a clamp and an upper pedestal bearing. The centers of curvature of the spherical surfaces of the shell lie upon the point. Pitch motion and roll motion are separately and independently imparted to mirror by a pair of pitch paddles and a pair of roll paddles that are independently and separately moved by control rods driven by motors.

  18. Mirror mount

    DOEpatents

    Humpal, H.H.

    1987-11-10

    A mirror mount is provided that allows free pitch, yaw and roll motion of the mirror while keeping the location of a point on the surface of the mirror fixed in the rest frame of reference of the mount. Yaw movement is provided by two yaw cylinders that are bearing mounted to provide rotation. Pitch and roll motion is provided by a spherically annular shell that is air bearing mounted to move between a clamp and an upper pedestal bearing. The centers of curvature of the spherical surfaces of the shell lie upon the point. Pitch motion and roll motion are separately and independently imparted to mirror by a pair of pitch paddles and a pair of roll paddles that are independently and separately moved by control rods driven by motors. 5 figs.

  19. Videometric head tracker for augmented reality applications

    NASA Astrophysics Data System (ADS)

    Janin, Adam L.; Zikan, Karel; Mizell, David; Banner, Mike; Sowizral, Henry A.

    1995-12-01

    For the past three years, we have been developing augmented reality technology for application to a variety of touch labor tasks in aircraft manufacturing and assembly. The system would be worn by factory workers to provide them with better-quality information for performing their tasks than was previously available. Using a see-through head-mounted display (HMD) whose optics are set at a focal length of about 18 in., the display and its associated head tracking system can be used to superimpose and stabilize graphics on the surface of a work piece. This technology would obviate many expensive marking systems now used in aerospace manufacturing. The most challenging technical issue with respect to factory applications of AR is head position and orientation tracking. It requires high accuracy, long- range tracking in a high-noise environment. The approach we have chosen uses a head- mounted miniature video camera. The user's wearable computer system utilizes the camera to find fiducial markings that have been placed on known coordinates on or near the work piece. The system then computes the user's position and orientation relative to the fiducial marks. It is referred to as a `videometric' head tracker. In this paper, we describe the steps we took and the results we obtained in the process of prototyping our videometric head tracker, beginning with analytical and simulation results, and continuing through the working prototypes.

  20. Carp head kidney leukocytes display different patterns of oxygen radical production after stimulation with PAMPs and DAMPs.

    PubMed

    Vera-Jimenez, N I; Nielsen, M E

    2013-10-01

    Wound healing and tissue regeneration are essential mechanisms to ensure the survival and health of any organism. Despite this, only a few studies have been devoted to study tissue regeneration during wound healing in fish. Reactive oxygen species (ROS), in particular hydrogen peroxide, play an important dual role both for promoting tissue repair, but also for eradication of pathogens. This study aims at dissecting the contribution of PAMPs (using β-glucan) and DAMPs in the respiratory burst response of carp head kidney-derived leukocytes, and address their contribution to wound healing processes. Consistent with a pathogen eradication strategy, ROS responses to PAMP stimulation (β-glucan) was fast, vigorous and highly dominated by production of superoxide anion. In contrast, stimulation with DAMPs led to a slow, subtle but long-lasting production of oxygen radicals dominated by hydrogen peroxide. Using an in vitro model of scratch-wounded CCB fibroblast cell cultures and a novel PhotoID proliferation assay, stimulation with low and continuous levels of hydrogen peroxide (5 μM) led to a slight increase in the percentage of wound recovery and thus promoted wound closure. In contrast, high doses of hydrogen peroxide (300 μM) impaired fibroblast scratch-wound recovery and caused cell death. These results elucidate the capacity of hydrogen peroxide to influence the fate of tissue regeneration through the establishment of environments suitable for promoting either tissue regeneration or oxidative stress and thereby potential tissue damage. Direct in vitro stimulation with β-glucans did not impact fibroblast scratch-wound recovery, which further suggests that interaction with tissue-resident leukocytes or other components of the fish immune system are required to induce fibroblast proliferation and thus for the accelerated wound healing promoted by β-glucan stimulation.

  1. Mirror mount

    DOEpatents

    Kuklo, Thomas C.; Bender, Donald A.

    1994-01-01

    A unique lens or mirror mount having adjustable constraints at two key locations to allow for "X" and "Y" tilts of the mirror only. The device uses two pair of flexures of a type such that the pivots of the mirror gimble are rigidly fixed in all planes allowing the device to have zero stacking tolerance and zero wear over time.

  2. Real-time simulation of combined short-wave and long-wave infrared vision on a head-up display

    NASA Astrophysics Data System (ADS)

    Peinecke, Niklas; Schmerwitz, Sven

    2014-05-01

    Landing under adverse weather conditions can be challenging, even if the airfields are well known to the pilots. This is true for civil as well as military aviation. Within the scope of this paper we concentrate especially on fog conditions. The work has been conducted within the project ALICIA. ALICIA is a research and development project co-funded by European Commission under the Seventh Framework Programme. ALICIA aims at developing new and scalable cockpit applications which can extend operations of aircraft in degraded conditions: All Conditions Operations. One of the systems developed is a head-up display that can display a generated symbology together with a raster-mode infrared image. We will detail how we implemented a real-time enabled simulation of a combined short-wave and long-wave infrared image for landing. A major challenge was to integrate several already existing simulation solutions, e.g., for visual simulation and sensors with the required data-bases. For the simulations DLRs in-house sensor simulation framework F3S was used, together with a commercially available airport model that had to be heavily modified in order to provide realistic infrared data. Special effort was invested for a realistic impression of runway lighting under foggy conditions. We will present results and sketch further improvements for future simulations.

  3. A green-color portable waveguide eyewear display system

    NASA Astrophysics Data System (ADS)

    Xia, Lingbo; Xu, Ke; Wu, Zhengming; Hu, Yingtian; Li, Zhenzhen; Wang, Yongtian; Liu, Juan

    2013-08-01

    Waveguide display systems are widely used in various display fields, especially in head mounted display. Comparing with the traditional head mounted display system, this device dramatically reduce the size and mass. However, there are still several fatal problems such as high scatting, the cumbersome design and chromatic aberration that should be solved. We designed and fabricated a monochromatic portable eyewear display system consist of a comfortable eyewear device and waveguide system with two holographic gratings located on the substrate symmetrically. We record the gratings on the photopolymer medium with high efficiency and wavelength sensitivity. The light emitting from the micro-display is diffracted by the grating and trapped in the glass substrate by total internal reflection. The relationship between the diffraction efficiency and exposure value is studied and analyzed, and we fabricated the gratings with appropriate diffraction efficiency in a optimization condition. To avoid the disturbance of the stray light, we optimize the waveguide system numerically and perform the optical experiments. With this system, people can both see through the waveguide to obtain the information outside and catch the information from the micro display. After considering the human body engineering and industrial production, we design the structure in a compact and portable way. It has the advantage of small-type configuration and economic acceptable. It is believe that this kind of planar waveguide system is a potentially replaceable choice for the portable devices in future mobile communications.

  4. Mirror mount

    DOEpatents

    Kuklo, T.C.; Bender, D.A.

    1994-10-04

    A unique lens or mirror mount having adjustable constraints at two key locations to allow for ''X'' and ''Y'' tilts of the mirror only is disclosed. The device uses two pair of flexures of a type such that the pivots of the mirror gimble are rigidly fixed in all planes allowing the device to have zero stacking tolerance and zero wear over time. 4 figs.

  5. Visual Processing: Implications for Helmet Mounted Displays

    DTIC Science & Technology

    1990-05-01

    Photometer (Model 1980A-PL). A Gerbrands 300-C Digital Millisecond Timer (Model 03C6) was used to control the exposure duration of the stimuli for all...dichoptic task). The order of eye presentation was randomized to counterbalance possible order effects. 3. RESULTS Post hoc examination of the luminance

  6. Military display market segment: wearable and portable

    NASA Astrophysics Data System (ADS)

    Desjardins, Daniel D.; Hopper, Darrel G.

    2003-09-01

    The military display market (MDM) is analyzed in terms of one of its segments, wearable and portable displays. Wearable and portable displays are those embedded in gear worn or carried by warfighters. Categories include hand-mobile (direct-view and monocular/binocular), palm-held, head/helmet-mounted, body-strapped, knee-attached, lap-born, neck-lanyard, and pocket/backpack-stowed. Some 62 fielded and developmental display sizes are identified in this wearable/portable MDM segment. Parameters requiring special consideration, such as weight, luminance ranges, light emission, viewing angles, and chromaticity coordinates, are summarized and compared. Ruggedized commercial versus commercial off-the-shelf designs are contrasted; and a number of custom displays are also found in this MDM category. Display sizes having aggregate quantities of 5,000 units or greater or having 2 or more program applications are identified. Wearable and portable displays are also analyzed by technology (LCD, LED, CRT, OLED and plasma). The technical specifications and program history of several high-profile military programs are discussed to provide a systems context for some representative displays and their function. As of August 2002 our defense-wide military display market study has documented 438,882 total display units distributed across 1,163 display sizes and 438 weapon systems. Wearable and portable displays account for 202,593 displays (46% of total DoD) yet comprise just 62 sizes (5% of total DoD) in 120 weapons systems (27% of total DoD). Some 66% of these wearable and portable applications involve low information content displays comprising just a few characters in one color; however, there is an accelerating trend towards higher information content units capable of showing changeable graphics, color and video.

  7. Using EMG to anticipate head motion for virtual-environment applications

    NASA Technical Reports Server (NTRS)

    Barniv, Yair; Aguilar, Mario; Hasanbelliu, Erion

    2005-01-01

    In virtual environment (VE) applications, where virtual objects are presented in a see-through head-mounted display, virtual images must be continuously stabilized in space in response to user's head motion. Time delays in head-motion compensation cause virtual objects to "swim" around instead of being stable in space which results in misalignment errors when overlaying virtual and real objects. Visual update delays are a critical technical obstacle for implementing head-mounted displays in applications such as battlefield simulation/training, telerobotics, and telemedicine. Head motion is currently measurable by a head-mounted 6-degrees-of-freedom inertial measurement unit. However, even given this information, overall VE-system latencies cannot be reduced under about 25 ms. We present a novel approach to eliminating latencies, which is premised on the fact that myoelectric signals from a muscle precede its exertion of force, thereby limb or head acceleration. We thus suggest utilizing neck-muscles' myoelectric signals to anticipate head motion. We trained a neural network to map such signals onto equivalent time-advanced inertial outputs. The resulting network can achieve time advances of up to 70 ms.

  8. 77 FR 31493 - Safety Zones; Fourth of July Fireworks Displays Within the Captain of the Port Charleston Zone, SC

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-05-29

    ... Displays on certain navigable waterways in Hilton Head Island, Mount Pleasant, Murrells Inlet, North... from the hazards associated with launching fireworks over navigable waters of the United States... purpose of the rule is to protect the public from the hazards associated with launching fireworks...

  9. Integrated primary flight display: the sky arc

    NASA Astrophysics Data System (ADS)

    Voulgaris, Theodore J.; Metalis, Sam A.; Mobley, R. S.

    1995-05-01

    Flight instrument interpretability has been a key piloting issue because it is directly related to operator performance and inversely related to operator error. To improve interpretability we have developed the Sky Arc, a new symbology initially developed for attitude control, particularly for a helmet-mounted display. It consists of an integrated set of graphic symbols which vary in a continuous, analog fashion with changing flight parameters. The Sky Arc currently integrates, pitch, roll, heading, air speed, and terrain avoidance. The display can be integrated into a head down display, a head up display, or a helmet mounted display. In this preliminary study the usability of the Sky Arc as an attitude indicator was compared to a conventional head-up display pitch ladder symbology. The test involved six test subject pilots and a medium-fidelity simulator. The pilots were asked to fully recover from a series of unusual attitude conditions that were presented on the simulator. The time taken to recover and the correctness of the recovery procedure served as the objective evaluation measures. A Likert-type rating scale and open-ended subject matter expert opinions served as the subjective measures of evaluation. To examine whether there was a relationship between usability of the attitude indicator and difficulty of the unusual attitude, the workload levels involved in performing the unusual attitude recoveries were grouped into three levels, low, medium, and high. At each workload level there were four conditions, for a total of 12 different conditions. Each pilot was asked to recovery twice from each condition, for a total of 24 unusual attitude recovery trials. The test trials were counterbalanced and displayed in a prearranged order. No differences due to difficulty of the unusual attitude were detected. Overall, the study revealed that the Sky Arc led to generally faster recoveries than did the standard display, as well as higher subjective preference ratings

  10. Color Head Down Display Program

    DTIC Science & Technology

    1993-04-01

    energy is converted 36 to the mission of UV light at a wavelength of 2537 A. Thw inner surface of the lamp is coned with phosphns selected to transform... rradiation of silicon with neunrns is known to beta of bipolar transistors and, therefore, increase the breakdown of the SOI floating substrate MOS...was also an incmse in leakage current after rradiation , but we were able to reduce it by doing a Postirradiation anneal 52 14- , 1 3 -e-- GILm Vbdn - 12

  11. Visualization of cortical, subcortical, and deep brain neural circuit dynamics during naturalistic mammalian behavior with head-mounted microscopes and chronically implanted lenses

    PubMed Central

    Resendez, Shanna L.; Jennings, Josh H.; Ung, Randall L.; Namboodiri, Vijay Mohan K.; Zhou, Zhe Charles; Otis, James M.; Nomura, Hiroshi; McHenry, Jenna A.; Kosyk, Oksana; Stuber, Garret D.

    2016-01-01

    Genetically encoded calcium indicators for visualizing dynamic cellular activity have greatly expanded our understanding of the brain. However, due to light scattering properties of the brain as well as the size and rigidity of traditional imaging technology, in vivo calcium imaging has been limited to superficial brain structures during head fixed behavioral tasks. This limitation can now be circumvented by utilizing miniature, integrated microscopes in conjunction with an implantable microendoscopic lens to guide light into and out of the brain, thus permitting optical access to deep brain (or superficial) neural ensembles during naturalistic behaviors. Here, we describe procedural steps to conduct such imaging studies using mice. However, we anticipate the protocol can be easily adapted for use in other small vertebrates. Successful completion of this protocol will permit cellular imaging of neuronal activity and the generation of data sets with sufficient statistical power to correlate neural activity with stimulus presentation, physiological state, and other aspects of complex behavioral tasks. This protocol takes 6–11 weeks to complete. PMID:26914316

  12. Visualization of cortical, subcortical and deep brain neural circuit dynamics during naturalistic mammalian behavior with head-mounted microscopes and chronically implanted lenses.

    PubMed

    Resendez, Shanna L; Jennings, Josh H; Ung, Randall L; Namboodiri, Vijay Mohan K; Zhou, Zhe Charles; Otis, James M; Nomura, Hiroshi; McHenry, Jenna A; Kosyk, Oksana; Stuber, Garret D

    2016-03-01

    Genetically encoded calcium indicators for visualizing dynamic cellular activity have greatly expanded our understanding of the brain. However, owing to the light-scattering properties of the brain, as well as the size and rigidity of traditional imaging technology, in vivo calcium imaging has been limited to superficial brain structures during head-fixed behavioral tasks. These limitations can now be circumvented by using miniature, integrated microscopes in conjunction with an implantable microendoscopic lens to guide light into and out of the brain, thus permitting optical access to deep brain (or superficial) neural ensembles during naturalistic behaviors. Here we describe steps to conduct such imaging studies using mice. However, we anticipate that the protocol can be easily adapted for use in other small vertebrates. Successful completion of this protocol will permit cellular imaging of neuronal activity and the generation of data sets with sufficient statistical power to correlate neural activity with stimulus presentation, physiological state and other aspects of complex behavioral tasks. This protocol takes 6-11 weeks to complete.

  13. Virtual displays for entertainment applications: hitting cost/performance with LED arrays

    NASA Astrophysics Data System (ADS)

    Karpman, Maurice S.; Wells, Ben A.

    1997-01-01

    Virtual displays have tremendous potential in entertainment applications such as video games, head mount displays for personal computers, and mobile World Wide Web viewers. These consumer applications require high quality virtual displays at a cost below $40 per eye. This combination of performance and cost is not realizable with virtual displays based on LCDs or CRTs. However, low cost, high quality virtual displays can be achieved using patented scanned linear array technology and red, green and blue monolithic LED arrays. A 384 by 224 full color virtual display prototype has been built using this approach. The prototype delivers 4-bits of grayscale per color and flicker-free performance at a 60 Hz frame refresh rate. This paper discuses details of our LED based full color virtual display prototype; development of red, green and blue monolithic LED arrays; and work-in- progress to miniaturize the display and scale the resolution to full VGA.

  14. Head tracker evaluation utilizing the dynamic tracker test fixture

    NASA Astrophysics Data System (ADS)

    La Moure Shattuck, Judson, III; Parisi, Vincent M., II; Smerdon, Arryn J.

    2007-04-01

    In military aviation, head tracker technologies have become increasingly important to track the pilot's head position and orientation, allowing the user to quickly interact with the operational environment. This technology allows the pilot to quickly acquire items of interest and see Fighter Data Link type information. Acquiring the target on a helmet-mounted tracker/display which can automatically slew a weapon's seeker is far more efficient than having to point at the target with the nose of the aircraft as previously required for the heads-up display (HUD) type of target acquisition. The United States Air Force (USAF) has used and evaluated a variety of helmet-mounted trackers for incorporation into their high performance aircrafts. The Dynamic Tracker Test Fixture (DTTF) was designed by the Helmet-Mounted Sensory Technology (HMST) laboratory to accurately measure rotation in one plane both static and dynamic conditions for the purpose of evaluating the accuracy of head trackers, including magnetic, inertial, and optical trackers. This paper describes the design, construction, capabilities, limitations, and performance of the DTTF.

  15. Mount St. Helens Rebirth

    NASA Technical Reports Server (NTRS)

    2002-01-01

    could be seen falling from the sky over the Great Plains, more than 1500 km distant. This image was acquired by Landsat 7 on Aug. 22, 1999. It was produced at 30-m resolution using bands 3, 2, and 1 to display red, green, and blue, respectively ('true color'). Some of the effects of the massive eruption on May 18, 1980, can still be seen clearly, especially on the northern and eastern flanks of Mount St. Helens, which are still mostly barren (shades of white and gray). The crater is in the center of the image. Note the streaking from the crater (gray on the image). These are the remnants of pyroclastic flows (superheated avalanches of gas, ash and pieces of rock) that carved deep channels down the slopes and onto the relatively flat areas near the base of the mountain. The partially-filled Spirit Lake can be seen just to the northeast of the crater (blue-black on the image), and the where most of the energy was directed during the blast is the gray area immediately to the northwest of the crater. However, on other parts of the mountain, the rejuvenation process is obvious. Ash deposits have supplied minerals which have accelerated vegetation growth (various shades of green). Though far from what it looked like 20 years ago, Mount St Helens is actively recovering. Data courtesy Landsat 7 project and EROS Data Center. Caption by James Foster, NASA Goddard Space Flight Center.

  16. 49 CFR 572.112 - Head assembly.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 7 2013-10-01 2013-10-01 false Head assembly. 572.112 Section 572.112... 50th Percentile Male § 572.112 Head assembly. The head assembly consists of the head (drawing 78051-61X...) accelerometers that are mounted in conformance to § 572.36 (c). (a) Test procedure. (1) Soak the head assembly...

  17. 49 CFR 572.112 - Head assembly.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 49 Transportation 7 2011-10-01 2011-10-01 false Head assembly. 572.112 Section 572.112... 50th Percentile Male § 572.112 Head assembly. The head assembly consists of the head (drawing 78051-61X...) accelerometers that are mounted in conformance to § 572.36 (c). (a) Test procedure. (1) Soak the head assembly...

  18. 49 CFR 572.112 - Head assembly.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 49 Transportation 7 2014-10-01 2014-10-01 false Head assembly. 572.112 Section 572.112... 50th Percentile Male § 572.112 Head assembly. The head assembly consists of the head (drawing 78051-61X...) accelerometers that are mounted in conformance to § 572.36 (c). (a) Test procedure. (1) Soak the head assembly...

  19. 49 CFR 572.112 - Head assembly.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 7 2010-10-01 2010-10-01 false Head assembly. 572.112 Section 572.112... 50th Percentile Male § 572.112 Head assembly. The head assembly consists of the head (drawing 78051-61X...) accelerometers that are mounted in conformance to § 572.36 (c). (a) Test procedure. (1) Soak the head assembly...

  20. Localization of Head-Mounted Vibrotactile Transducers

    DTIC Science & Technology

    2013-02-01

    hair gel, yet her results fell within the range achieved by her male counterparts. Additionally, during equipment pilot testing , a few researchers of... follicles themselves are aiding in tactor detection and identification as their hair strands are subjected to the stimuli. This result is anecdotal...14 4.4 The Effect of Hair

  1. Thin optical display panel

    DOEpatents

    Veligdan, James Thomas

    1997-01-01

    An optical display includes a plurality of optical waveguides each including a cladding bound core for guiding internal display light between first and second opposite ends by total internal reflection. The waveguides are stacked together to define a collective display thickness. Each of the cores includes a heterogeneous portion defining a light scattering site disposed longitudinally between the first and second ends. Adjacent ones of the sites are longitudinally offset from each other for forming a longitudinal internal image display over the display thickness upon scattering of internal display light thereagainst for generating a display image. In a preferred embodiment, the waveguides and scattering sites are transparent for transmitting therethrough an external image in superposition with the display image formed by scattering the internal light off the scattering sites for defining a heads up display.

  2. I-PORT: new "hands-free" near-eye display

    NASA Astrophysics Data System (ADS)

    Carollo, Jerome T.; Hoppe, Michael

    2007-04-01

    The patent pending I-PORT TM is a highly versatile, hands-free, low profile near-eye display system. It was originally designed with the medical market in mind as a data (monocular) or surgical (binocular) head worn display. The concept takes advantage of a technique used with surgical loupes where they are sometimes mounted "into" eyeglasses. The I-PORT TMdisplay module is similarly mounted onto or into the spectacle lens of protective eyewear or sunglasses. The I-PORT TM is capable of various fields of view and resolutions while being low profile providing minimal obscuration. It is an ideal remote viewer for medical, military and commercial equipment. Our system is capable of producing fields of view greater than 50 degrees in full color and can incorporate either organic light emitting diode, (OLED) or active matrix liquid crystal display (AMLCD) image sources of various resolutions.

  3. Projection-type see-through holographic three-dimensional display

    PubMed Central

    Wakunami, Koki; Hsieh, Po-Yuan; Oi, Ryutaro; Senoh, Takanori; Sasaki, Hisayuki; Ichihashi, Yasuyuki; Okui, Makoto; Huang, Yi-Pai; Yamamoto, Kenji

    2016-01-01

    Owing to the limited spatio-temporal resolution of display devices, dynamic holographic three-dimensional displays suffer from a critical trade-off between the display size and the visual angle. Here we show a projection-type holographic three-dimensional display, in which a digitally designed holographic optical element and a digital holographic projection technique are combined to increase both factors at the same time. In the experiment, the enlarged holographic image, which is twice as large as the original display device, projected on the screen of the digitally designed holographic optical element was concentrated at the target observation area so as to increase the visual angle, which is six times as large as that for a general holographic display. Because the display size and the visual angle can be designed independently, the proposed system will accelerate the adoption of holographic three-dimensional displays in industrial applications, such as digital signage, in-car head-up displays, smart-glasses and head-mounted displays. PMID:27694975

  4. Projection-type see-through holographic three-dimensional display

    NASA Astrophysics Data System (ADS)

    Wakunami, Koki; Hsieh, Po-Yuan; Oi, Ryutaro; Senoh, Takanori; Sasaki, Hisayuki; Ichihashi, Yasuyuki; Okui, Makoto; Huang, Yi-Pai; Yamamoto, Kenji

    2016-10-01

    Owing to the limited spatio-temporal resolution of display devices, dynamic holographic three-dimensional displays suffer from a critical trade-off between the display size and the visual angle. Here we show a projection-type holographic three-dimensional display, in which a digitally designed holographic optical element and a digital holographic projection technique are combined to increase both factors at the same time. In the experiment, the enlarged holographic image, which is twice as large as the original display device, projected on the screen of the digitally designed holographic optical element was concentrated at the target observation area so as to increase the visual angle, which is six times as large as that for a general holographic display. Because the display size and the visual angle can be designed independently, the proposed system will accelerate the adoption of holographic three-dimensional displays in industrial applications, such as digital signage, in-car head-up displays, smart-glasses and head-mounted displays.

  5. Projection-type see-through holographic three-dimensional display.

    PubMed

    Wakunami, Koki; Hsieh, Po-Yuan; Oi, Ryutaro; Senoh, Takanori; Sasaki, Hisayuki; Ichihashi, Yasuyuki; Okui, Makoto; Huang, Yi-Pai; Yamamoto, Kenji

    2016-10-03

    Owing to the limited spatio-temporal resolution of display devices, dynamic holographic three-dimensional displays suffer from a critical trade-off between the display size and the visual angle. Here we show a projection-type holographic three-dimensional display, in which a digitally designed holographic optical element and a digital holographic projection technique are combined to increase both factors at the same time. In the experiment, the enlarged holographic image, which is twice as large as the original display device, projected on the screen of the digitally designed holographic optical element was concentrated at the target observation area so as to increase the visual angle, which is six times as large as that for a general holographic display. Because the display size and the visual angle can be designed independently, the proposed system will accelerate the adoption of holographic three-dimensional displays in industrial applications, such as digital signage, in-car head-up displays, smart-glasses and head-mounted displays.

  6. PV module mounting method and mounting assembly

    DOEpatents

    Lenox, Carl J.S.; Johnson, Kurt M.

    2013-04-23

    A method for mounting PV modules to a deck includes selecting PV module layout pattern so that adjacent PV module edges are spaced apart. PV mounting and support assemblies are secured to the deck according to the layout pattern using fasteners extending into the deck. The PV modules are placed on the PV mounting and support assemblies. Retaining elements are located over and secured against the upper peripheral edge surfaces of the PV modules so to secure them to the deck with the peripheral edges of the PV modules spaced apart from the deck. In some examples a PV module mounting assembly, for use on a shingled deck, comprises flashing, a base mountable on the flashing, a deck-penetrating fastener engageable with the base and securable to the deck so to secure the flashing and the base to the shingled deck, and PV module mounting hardware securable to the base.

  7. Magnetic core mounting system

    DOEpatents

    Ronning, Jeffrey J.

    2002-01-01

    A mounting apparatus for an electromagnetic device such as a transformer of inductor includes a generally planar metallic plate as a first heat sink, and a metallic mounting cup as a second heat sink. The mounting cup includes a cavity configured to receive the electromagnetic device, the cavity being defined by a base, and an axially-extending annular sidewall extending from the base to a flange portion of the mounting cup. The mounting cup includes first and second passages for allowing the leads of first and second windings of the electromagnetic device to be routed out of the cavity. The cavity is filled with a polyurethane potting resin, and the mounting cup, including the potted electromagnetic device, is mounted to the plate heat sink using fasteners. The mounting cup, which surrounds the electromagnetic device, in combination with the potting resin provides improved thermal transfer to the plate heat sink, as well as providing resistance to vibration and shocks.

  8. Fixed mount wavefront sensor

    DOEpatents

    Neal, Daniel R.

    2000-01-01

    A rigid mount and method of mounting for a wavefront sensor. A wavefront dissector, such as a lenslet array, is rigidly mounted at a fixed distance relative to an imager, such as a CCD camera, without need for a relay imaging lens therebetween.

  9. Fitness activity classification by using multiclass support vector machines on head-worn sensors.

    PubMed

    Loh, Darrell; Lee, Tien J; Zihajehzadeh, Shaghayegh; Hoskinson, Reynald; Park, Edward J

    2015-08-01

    Fitness activity classification on wearable devices can provide activity-specific information and generate more accurate performance metrics. Recently, optical head-mounted displays (OHMD) like Google Glass, Sony SmartEyeglass and Recon Jet have emerged. This paper presents a novel method to classify fitness activities using head-worn accelerometer, barometric pressure sensor and GPS, with comparisons to other common mounting locations on the body. Using multiclass SVM on head-worn sensors, we obtained an average F-score of 96.66% for classifying standing, walking, running, ascending/descending stairs and cycling. The best sensor location combinations were found to be on the ankle plus another upper body location. Using three or more sensors did not show a notable improvement over the best two-sensor combinations.

  10. A method for generating enhanced vision displays using OpenGL video texture

    NASA Astrophysics Data System (ADS)

    Bernier, Kenneth L.

    2010-04-01

    Degraded visual conditions can marvel the curious and destroy the unprepared. While navigation instruments are trustworthy companions, true visual reference remains king of the hills. Poor visibility may be overcome via imaging sensors such as low light level charge-coupled-device, infrared, and millimeter wave radar. Enhanced Vision systems combine this imagery into a comprehensive situation awareness display, presented to the pilot as reference imagery on a cockpit display, or as world-conformal imagery on head-up or head-mounted displays. This paper demonstrates that Enhanced Vision imaging can be achieved at video rates using typical CPU / GPU architecture, standard video capture hardware, dynamic non-linear ray tracing algorithms, efficient image transfer methods, and simple OpenGL rendering techniques.

  11. Photovoltaic module mounting system

    SciTech Connect

    Miros, Robert H. J.; Mittan, Margaret Birmingham; Seery, Martin N; Holland, Rodney H

    2012-04-17

    A solar array mounting system having unique installation, load distribution, and grounding features, and which is adaptable for mounting solar panels having no external frame. The solar array mounting system includes flexible, pedestal-style feet and structural links connected in a grid formation on the mounting surface. The photovoltaic modules are secured in place via the use of attachment clamps that grip the edge of the typically glass substrate. The panel mounting clamps are then held in place by tilt brackets and/or mid-link brackets that provide fixation for the clamps and align the solar panels at a tilt to the horizontal mounting surface. The tilt brackets are held in place atop the flexible feet and connected link members thus creating a complete mounting structure.

  12. Photovoltaic module mounting system

    SciTech Connect

    Miros, Robert H. J.; Mittan, Margaret Birmingham; Seery, Martin N; Holland, Rodney H

    2012-09-18

    A solar array mounting system having unique installation, load distribution, and grounding features, and which is adaptable for mounting solar panels having no external frame. The solar array mounting system includes flexible, pedestal-style feet and structural links connected in a grid formation on the mounting surface. The photovoltaic modules are secured in place via the use of attachment clamps that grip the edge of the typically glass substrate. The panel mounting clamps are then held in place by tilt brackets and/or mid-link brackets that provide fixation for the clamps and align the solar panels at a tilt to the horizontal mounting surface. The tilt brackets are held in place atop the flexible feet and connected link members thus creating a complete mounting structure.

  13. VISTA NF-16D programmable display system development

    NASA Astrophysics Data System (ADS)

    Bailey, Randall E.; Landers, Thomas F.

    1998-08-01

    Wright Laboratory's Variable-Stability In-Flight Simulator Test Aircraft (VISTA) NF-16D is the newest in-flight simulator in the USAF inventory. This unique research aircraft will perform a multitude of missions: evaluate flight characteristics of new aircraft that have not yet flown, perform research in the areas of flying qualities, flight control design, pilot-vehicle interface, weapons and avionics integration, and train test pilots and engineers. The VISTA is being upgraded to enhance its simulation fidelity and its research capabilities through the addition of a programmable Helmet-Mounted Display (HMD) and Head-up Display (HUD) in the front cockpit. The programmable HMD system consists of a GEC Marconi Avionics Viper II Helmet- Mounted Optics Module integrate with a modified Helmet Integrated Systems Limited HGU-86/P helmet, the Honeywell Advanced Metal Tolerant tracker, and a GEC-Marconi Avionics Programmable Display Generator. The monocular HMD system is designed for growth to stroke-on-video, binocular capability. Lessons-learned in the VISTA HMD development are reviewed. An outline of the proposed VISTA HMD demonstration flight is given to highlight the VISTA programmable display system capabilities.

  14. High bandwidth optical mount

    DOEpatents

    Bender, Donald A.; Kuklo, Thomas

    1994-01-01

    An optical mount, which directs a laser beam to a point by controlling the position of a light-transmitting optic, is stiffened so that a lowest resonant frequency of the mount is approximately one kilohertz. The optical mount, which is cylindrically-shaped, positions the optic by individually moving a plurality of carriages which are positioned longitudinally within a sidewall of the mount. The optical mount is stiffened by allowing each carriage, which is attached to the optic, to move only in a direction which is substantially parallel to a center axis of the optic. The carriage is limited to an axial movement by flexures or linear bearings which connect the carriage to the mount. The carriage is moved by a piezoelectric transducer. By limiting the carriage to axial movement, the optic can be kinematically clamped to a carriage.

  15. High bandwidth optical mount

    DOEpatents

    Bender, D.A.; Kuklo, T.

    1994-11-08

    An optical mount, which directs a laser beam to a point by controlling the position of a light-transmitting optic, is stiffened so that a lowest resonant frequency of the mount is approximately one kilohertz. The optical mount, which is cylindrically-shaped, positions the optic by individually moving a plurality of carriages which are positioned longitudinally within a sidewall of the mount. The optical mount is stiffened by allowing each carriage, which is attached to the optic, to move only in a direction which is substantially parallel to a center axis of the optic. The carriage is limited to an axial movement by flexures or linear bearings which connect the carriage to the mount. The carriage is moved by a piezoelectric transducer. By limiting the carriage to axial movement, the optic can be kinematically clamped to a carriage. 5 figs.

  16. Rapid jetting status inspection and accurate droplet volume measurement for a piezo drop-on-demand inkjet print head using a scanning mirror for display applications

    NASA Astrophysics Data System (ADS)

    Shin, Dong-Youn; Kim, Minsung

    2017-02-01

    Despite the inherent fabrication simplicity of piezo drop-on-demand inkjet printing, the non-uniform deposition of colourants or electroluminescent organic materials leads to faulty display products, and hence, the importance of rapid jetting status inspection and accurate droplet volume measurement increases from a process perspective. In this work, various jetting status inspections and droplet volume measurement methods are reviewed by discussing their advantages and disadvantages, and then, the opportunities for the developed prototype with a scanning mirror are explored. This work demonstrates that jetting status inspection of 384 fictitious droplets can be performed within 17 s with maximum and minimum measurement accuracies of 0.2 ± 0.5 μ m for the fictitious droplets of 50 μ m in diameter and -1.2 ± 0.3 μ m for the fictitious droplets of 30 μ m in diameter, respectively. In addition to the new design of an inkjet monitoring instrument with a scanning mirror, two novel methods to accurately measure the droplet volume by amplifying a minute droplet volume difference and then converting to other physical properties are suggested and the droplet volume difference of ±0.3% is demonstrated to be discernible using numerical simulations, even with the low measurement accuracy of 1 μ m . When the fact is considered that the conventional vision-based method with a CCD camera requires the optical measurement accuracy less than 25 nm to measure the volume of an in-flight droplet in the nominal diameter of 50 μ m at the same volume measurement accuracy, the suggested method with the developed prototype offers a whole new opportunity to inkjet printing for display applications.

  17. Rapid jetting status inspection and accurate droplet volume measurement for a piezo drop-on-demand inkjet print head using a scanning mirror for display applications.

    PubMed

    Shin, Dong-Youn; Kim, Minsung

    2017-02-01

    Despite the inherent fabrication simplicity of piezo drop-on-demand inkjet printing, the non-uniform deposition of colourants or electroluminescent organic materials leads to faulty display products, and hence, the importance of rapid jetting status inspection and accurate droplet volume measurement increases from a process perspective. In this work, various jetting status inspections and droplet volume measurement methods are reviewed by discussing their advantages and disadvantages, and then, the opportunities for the developed prototype with a scanning mirror are explored. This work demonstrates that jetting status inspection of 384 fictitious droplets can be performed within 17 s with maximum and minimum measurement accuracies of 0.2 ± 0.5 μm for the fictitious droplets of 50 μm in diameter and -1.2 ± 0.3 μm for the fictitious droplets of 30 μm in diameter, respectively. In addition to the new design of an inkjet monitoring instrument with a scanning mirror, two novel methods to accurately measure the droplet volume by amplifying a minute droplet volume difference and then converting to other physical properties are suggested and the droplet volume difference of ±0.3% is demonstrated to be discernible using numerical simulations, even with the low measurement accuracy of 1 μm. When the fact is considered that the conventional vision-based method with a CCD camera requires the optical measurement accuracy less than 25 nm to measure the volume of an in-flight droplet in the nominal diameter of 50 μm at the same volume measurement accuracy, the suggested method with the developed prototype offers a whole new opportunity to inkjet printing for display applications.

  18. Man-in-the-loop study of filtering in airborne head tracking tasks

    NASA Technical Reports Server (NTRS)

    Lifshitz, S.; Merhav, S. J.

    1992-01-01

    A human-factors study is conducted of problems due to vibrations during the use of a helmet-mounted display (HMD) in tracking tasks whose major factors are target motion and head vibration. A method is proposed for improving aiming accuracy in such tracking tasks on the basis of (1) head-motion measurement and (2) the shifting of the reticle in the HMD in ways that inhibit much of the involuntary apparent motion of the reticle, relative to the target, and the nonvoluntary motion of the teleoperated device. The HMD inherently furnishes the visual feedback required by this scheme.

  19. Maneuvering impact boring head

    DOEpatents

    Zollinger, W.T.; Reutzel, E.W.

    1998-08-18

    An impact boring head may comprise a main body having an internal cavity with a front end and a rear end. A striker having a head end and a tail end is slidably mounted in the internal cavity of the main body so that the striker can be reciprocated between a forward position and an aft position in response to hydraulic pressure. A compressible gas contained in the internal cavity between the head end of the striker and the front end of the internal cavity returns the striker to the aft position upon removal of the hydraulic pressure. 8 figs.

  20. Maneuvering impact boring head

    DOEpatents

    Zollinger, W. Thor; Reutzel, Edward W.

    1998-01-01

    An impact boring head may comprise a main body having an internal cavity with a front end and a rear end. A striker having a head end and a tail end is slidably mounted in the internal cavity of the main body so that the striker can be reciprocated between a forward position and an aft position in response to hydraulic pressure. A compressible gas contained in the internal cavity between the head end of the striker and the front end of the internal cavity returns the striker to the aft position upon removal of the hydraulic pressure.

  1. Enhanced spatial-state feedback for night-vision goggle displays

    NASA Astrophysics Data System (ADS)

    Bachelder, Edward N.; Hansman, R. John, Jr.

    1997-06-01

    A preliminary study was conducted to investigate the use of visual flow cues as an aid to ground and vertical drift awareness during helicopter flight and targeting while using night vision goggles (NVGs). Three displays wee compared: (1) NVG display: simulated NVG image of cockpit and external environment. (2) Overlay display: NVG image with an overlay display but with symbology flow cue field and a surrounding wire-frame globe; (3) Cut-out display: same as the overlay display but with symbology removed from the central region. Three levels of contrast were also compared using each display type. The visual scenery was displayed to subjects using a helmet-mounted virtual reality device that had a 40 by 50 degree field-of-view liquid crystal display. The study involved six pilots. Three tasks were given: (1) Search task: designate enemy targets with a helmet-mounted sight; (2) Hover task: null out all transnational and yaw rates while in a hover; (3) Search/Hover task: perform both Search and Hover tasks simultaneously. These tasks were conducted in a fixed-based helicopter simulator which used the dynamics of a small-scale model helicopter. The following performance measures were collected: (1) Pilot ability to detect and recognize targets; (2) Pilots ability to null transnational and yaw rates; (3) Time scanning the instrument panel. Subjects also rated displays for efficacy in completing the three tasks. Target detection scores conducted during the Search and Search/Hover tasks were highest using the NVG display, followed by the cut-out display. Root-mean-square (RMS) drift rate error was comparable for all display types in the Hover and Hover/Search tasks, however RMS control input activity in all the translational axes was significantly higher in both rate-cueing displays than with the NVG display. From the control input and drift rate time histories it appears that the motion cues were more compelling in the overlay and cut- out displays than those perceived

  2. Stable mirror mount

    DOEpatents

    Cutburth, Ronald W.

    1990-01-01

    An improved mirror mount assembly is disclosed. The mirror mount assembly provides a post assembly slidable in a Y-axis orientation and a nut plate assembly slidable in an X-axis orientation and a device for simultaneously locking the post assembly and the key assembly in a fixed position.

  3. Stable mirror mount

    DOEpatents

    Cutburth, R.W.

    1983-11-04

    An improved mirror mount assembly is disclosed. The mirror mount assembly provides a post assembly slidable in a Y-axis orientation and a nut plate assembly slidable in an X-axis orientation and means for simultaneously locking said post assembly and said key assembly in a fixed position.

  4. Spherical mirror mount

    NASA Technical Reports Server (NTRS)

    Meyer, Jay L. (Inventor); Messick, Glenn C. (Inventor); Nardell, Carl A. (Inventor); Hendlin, Martin J. (Inventor)

    2011-01-01

    A spherical mounting assembly for mounting an optical element allows for rotational motion of an optical surface of the optical element only. In that regard, an optical surface of the optical element does not translate in any of the three perpendicular translational axes. More importantly, the assembly provides adjustment that may be independently controlled for each of the three mutually perpendicular rotational axes.

  5. Motion parallax in immersive cylindrical display systems

    NASA Astrophysics Data System (ADS)

    Filliard, N.; Reymond, G.; Kemeny, A.; Berthoz, A.

    2012-03-01

    Motion parallax is a crucial visual cue produced by translations of the observer for the perception of depth and selfmotion. Therefore, tracking the observer viewpoint has become inevitable in immersive virtual (VR) reality systems (cylindrical screens, CAVE, head mounted displays) used e.g. in automotive industry (style reviews, architecture design, ergonomics studies) or in scientific studies of visual perception. The perception of a stable and rigid world requires that this visual cue be coherent with other extra-retinal (e.g. vestibular, kinesthetic) cues signaling ego-motion. Although world stability is never questioned in real world, rendering head coupled viewpoint in VR can lead to the perception of an illusory perception of unstable environments, unless a non-unity scale factor is applied on recorded head movements. Besides, cylindrical screens are usually used with static observers due to image distortions when rendering image for viewpoints different from a sweet spot. We developed a technique to compensate in real-time these non-linear visual distortions, in an industrial VR setup, based on a cylindrical screen projection system. Additionally, to evaluate the amount of discrepancies tolerated without perceptual distortions between visual and extraretinal cues, a "motion parallax gain" between the velocity of the observer's head and that of the virtual camera was introduced in this system. The influence of this artificial gain was measured on the gait stability of free-standing participants. Results indicate that, below unity, gains significantly alter postural control. Conversely, the influence of higher gains remains limited, suggesting a certain tolerance of observers to these conditions. Parallax gain amplification is therefore proposed as a possible solution to provide a wider exploration of space to users of immersive virtual reality systems.

  6. Orbital Welding Head Held By Robot

    NASA Technical Reports Server (NTRS)

    Gangl, Kenneth J.; Graham, Benny F.; Nesmith, Malcolm F.; Mcferrin, David C.

    1992-01-01

    Orbital welding head positioned by robot controls motion and voltage of arc-welding torch mounted in head. New head encircles part at torch end, and held and manipulated by robot arm at opposite end. Entire welding operation automated. Useful for operations in hazardous environments.

  7. Three-dimensional visualization and display technologies; Proceedings of the Meeting, Los Angeles, CA, Jan. 18-20, 1989

    NASA Astrophysics Data System (ADS)

    Robbins, Woodrow E.; Fisher, Scott S.

    1989-09-01

    Special attention was given to problems of stereoscopic display devices, such as CAD for enhancement of the design process in visual arts, stereo-TV improvement of remote manipulator performance, a voice-controlled stereographic video camera system, and head-mounted displays and their low-cost design alternatives. Also discussed was a novel approach to chromostereoscopic microscopy, computer-generated barrier-strip autostereography and lenticular stereograms, and parallax barrier three-dimensional TV. Additional topics include processing and user interface isssues and visualization applications, including automated analysis and fliud flow topology, optical tomographic measusrements of mixing fluids, visualization of complex data, visualization environments, and visualization management systems.

  8. Three-dimensional visualization and display technologies; Proceedings of the Meeting, Los Angeles, CA, Jan. 18-20, 1989

    NASA Technical Reports Server (NTRS)

    Robbins, Woodrow E. (Editor); Fisher, Scott S. (Editor)

    1989-01-01

    Special attention was given to problems of stereoscopic display devices, such as CAD for enhancement of the design process in visual arts, stereo-TV improvement of remote manipulator performance, a voice-controlled stereographic video camera system, and head-mounted displays and their low-cost design alternatives. Also discussed was a novel approach to chromostereoscopic microscopy, computer-generated barrier-strip autostereography and lenticular stereograms, and parallax barrier three-dimensional TV. Additional topics include processing and user interface isssues and visualization applications, including automated analysis and fliud flow topology, optical tomographic measusrements of mixing fluids, visualization of complex data, visualization environments, and visualization management systems.

  9. The effect of hair density on the coupling between the tactor and the skin of the human head.

    PubMed

    Myles, Kimberly; Kalb, Joel T; Lowery, Janea; Kattel, Bheem P

    2015-05-01

    The purpose of this study was to determine the effect of hair density on vibration detection thresholds associated with the perception of low frequency vibration stimuli applied to the head. A host of tactile sensitivity information exists for other parts of the body, however the same information is lacking for the head. Thirty-three college students, age 18-35, were recruited for the study. A mixed design was used to evaluate the effect of hair density, head location, and frequency on vibration detection thresholds. Results suggest that hair density might slightly impede vibration signals from reaching the scalp and reduce vibration sensitivity, for the least sensitive locations on the head. This research provides design recommendations for head-mounted tactile displays for women and those with hair that can be used to convey directional cues for navigation and as alerts to critical events in the environment.

  10. Defense display market assessment

    NASA Astrophysics Data System (ADS)

    Desjardins, Daniel D.; Hopper, Darrel G.

    1998-09-01

    This paper addresses the number, function and size of principal military displays and establishes a basis to determine the opportunities for technology insertion in the immediate future and into the next millennium. Principal military displays are defined as those occupying appreciable crewstation real-estate and/or those without which the platform could not carry out its intended mission. DoD 'office' applications are excluded from this study. The military displays market is specified by such parameters as active area and footprint size, and other characteristics such as luminance, gray scale, resolution, angle, color, video capability, and night vision imaging system (NVIS) compatibility. Funded, future acquisitions, planned and predicted crewstation modification kits, and form-fit upgrades are taken into account. This paper provides an overview of the DoD niche market, allowing both government and industry a necessary reference by which to meet DoD requirements for military displays in a timely and cost-effective manner. The aggregate DoD market for direct-view and large-area military displays is presently estimated to be in excess of 242,000. Miniature displays are those which must be magnified to be viewed, involve a significantly different manufacturing paradigm and are used in helmet mounted displays and thermal weapon sight applications. Some 114,000 miniature displays are presently included within Service weapon system acquisition plans. For vendor production planning purposes it is noted that foreign military sales could substantially increase these quantities. The vanishing vendor syndrome (VVS) for older display technologies continues to be a growing, pervasive problem throughout DoD, which consequently must leverage the more modern display technologies being developed for civil- commercial markets.

  11. Simulator evaluation of display concepts for pilot monitoring and control of space shuttle approach and landing. Phase 2: Manual flight control

    NASA Technical Reports Server (NTRS)

    Gartner, W. B.; Baldwin, K. M.

    1973-01-01

    A study of the display requirements for final approach management of the space shuttle orbiter vehicle is presented. An experimental display concept, providing a more direct, pictorial representation of the vehicle's movement relative to the selected approach path and aiming points, was developed and assessed as an aid to manual flight path control. Both head-up, windshield projections and head-down, panel mounted presentations of the experimental display were evaluated in a series of simulated orbiter approach sequence. Data obtained indicate that the experimental display would enable orbiter pilots to exercise greater flexibility in implementing alternative final approach control strategies. Touchdown position and airspeed dispersion criteria were satisfied on 91 percent of the approach sequences, representing various profile and wind effect conditions. Flight path control and airspeed management satisfied operationally-relevant criteria for the two-segment, power-off orbiter approach and were consistently more accurate and less variable when the full set of experimental display elements was available to the pilot. Approach control tended to be more precise when the head-up display was used; however, the data also indicate that the head-down display would provide adequate support for the manual control task.

  12. NIF small mirror mount

    SciTech Connect

    McCarville, T

    1999-07-01

    A number of small mirror mounts have been identified that meet the stringent stability, wave front, and cleanliness standards of the NIF. These requirements are similar to those required in other performance critical optical design applications. Future design teams would conserve time and effort if recognized standards were established for mirror mount design and performance characteristics. Standards for stability, physical features, wave front distortion, and cleanliness would simplify the qualification process considerably. At this point such standards are not difficult to define, as the technical support work has been performed repeatedly by mirror mount consumers and suppliers.

  13. 1. PANORAMA, FROM ULAKTA HEAD COMMAND POST TO THE WEST ...

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

    1. PANORAMA, FROM ULAKTA HEAD COMMAND POST TO THE WEST TOWARD MOUNT BALLYHOO - Naval Operating Base Dutch Harbor & Fort Mears, Ulakta Head Fixed Defense Battery Command Post No. 1, Unalaska, Aleutian Islands, AK

  14. PANORAMA, FROM ULAKTA HEAD COMMAND POST TO THE WEST TOWARDS ...

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

    PANORAMA, FROM ULAKTA HEAD COMMAND POST TO THE WEST TOWARDS MOUNT BALLYHOO - Naval Operating Base Dutch Harbor & Fort Mears, Ulakta Head Fixed Defense Battery Command Post No. 1, Unalaska, Aleutian Islands, AK

  15. Mounting for ceramic scroll

    DOEpatents

    Petty, Jack D.

    1993-01-01

    A mounting for a ceramic scroll on a metal engine block of a gas turbine engine includes a first ceramic ring and a pair of cross key connections between the first ceramic ring, the ceramic scroll, and the engine block. The cross key connections support the scroll on the engine block independent of relative radial thermal growth and for bodily movement toward an annular mounting shoulder on the engine. The scroll has an uninterrupted annular shoulder facing the mounting shoulder on the engine block. A second ceramic ring is captured between mounting shoulder and the uninterrupted shoulder on the scroll when the latter is bodily shifted toward the mouting shoulder to define a gas seal between the scroll and the engine block.

  16. Mechanical strain isolator mount

    NASA Technical Reports Server (NTRS)

    James, Gordon E. (Inventor)

    1991-01-01

    Certain devices such as optical instruments must preserve their alignmental integrity while being subjected to mechanical strain. A mechanical strain isolator mount is provided to preserve the alignmental integrity of an alignment sensitive instrument. An alignment sensitive instrument is mounted on a rectangular base. Flexural legs are connected at their proximal ends to the rectangular base. Flexural legs are also spaced parallel to the sides. Mounting pads are connected to the legs at the distal end and the mechanical strain isolator mount is attached to the substrate by means of threaded bolts. When a mounting pad and its respective leg is subjected to lateral strain in either the X or Y direction via the substrate, the respective leg relieves the strain by bending in the direction of the strain. An axial strain on a mounting pad in the Z direction is relieved by a rotational motion of the legs in the direction of the strain. When the substrate is stress free, the flexural legs return to their original condition and thus preserve the original alignment integrity of the alignment sensitive instrument.

  17. Recent research results in stereo 3-D pictorial displays at Langley Research Center

    NASA Technical Reports Server (NTRS)

    Parrish, Russell V.; Busquets, Anthony M.; Williams, Steven P.

    1990-01-01

    Recent results from a NASA-Langley program which addressed stereo 3D pictorial displays from a comprehensive standpoint are reviewed. The program dealt with human factors issues and display technology aspects, as well as flight display applications. The human factors findings include addressing a fundamental issue challenging the application of stereoscopic displays in head-down flight applications, with the determination that stereoacuity is unaffected by the short-term use of stereo 3D displays. While stereoacuity has been a traditional measurement of depth perception abilities, it is a measure of relative depth, rather than actual depth (absolute depth). Therefore, depth perception effects based on size and distance judgments and long-term stereo exposure remain issues to be investigated. The applications of stereo 3D to pictorial flight displays within the program have repeatedly demonstrated increases in pilot situational awareness and task performance improvements. Moreover, these improvements have been obtained within the constraints of the limited viewing volume available with conventional stereo displays. A number of stereo 3D pictorial display applications are described, including recovery from flight-path offset, helicopter hover, and emulated helmet-mounted display.

  18. Flight Simulator Evaluation of Display Media Devices for Synthetic Vision Concepts

    NASA Technical Reports Server (NTRS)

    Arthur, J. J., III; Williams, Steven P.; Prinzel, Lawrence J., III; Kramer, Lynda J.; Bailey, Randall E.

    2004-01-01

    The Synthetic Vision Systems (SVS) Project of the National Aeronautics and Space Administration's (NASA) Aviation Safety Program (AvSP) is striving to eliminate poor visibility as a causal factor in aircraft accidents as well as enhance operational capabilities of all aircraft. To accomplish these safety and capacity improvements, the SVS concept is designed to provide a clear view of the world around the aircraft through the display of computer-generated imagery derived from an onboard database of terrain, obstacle, and airport information. Display media devices with which to implement SVS technology that have been evaluated so far within the Project include fixed field of view head up displays and head down Primary Flight Displays with pilot-selectable field of view. A simulation experiment was conducted comparing these display devices to a fixed field of view, unlimited field of regard, full color Helmet-Mounted Display system. Subject pilots flew a visual circling maneuver in IMC at a terrain-challenged airport. The data collected for this experiment is compared to past SVS research studies.

  19. Vibration isolation mounting system

    NASA Technical Reports Server (NTRS)

    Carter, Sam D. (Inventor); Bastin, Paul H. (Inventor)

    1995-01-01

    A system is disclosed for mounting a vibration producing device onto a spacecraft structure and also for isolating the vibration forces thereof from the structure. The system includes a mount on which the device is securely mounted and inner and outer rings. The rings and mount are concentrically positioned. The system includes a base (secured to the structure) and a set of links which are interconnected by a set of torsion bars which allow and resist relative rotational movement therebetween. The set of links are also rotatably connected to a set of brackets which are rigidly connected to the outer ring. Damped leaf springs interconnect the inner and outer rings and the mount allow relative translational movement therebetween in X and Y directions. The links, brackets and base are interconnected and configured so that they allow and resist translational movement of the device in the Z direction so that in combination with the springs they provide absorption of vibrational energy produced by the device in all three dimensions while providing rotational stiffness about all three axes to prevent undesired rotational motions.

  20. Heater head for a Stirling engine

    SciTech Connect

    Darooka, D.K.

    1988-09-06

    A heater head is described for a compound Stirling engine modules, each including a displacer cylinder coaxially aligned with the displacer cylinder of the other of the engine modules, a displacer piston mounted for reciprocation in the displacer cylinder.

  1. Display Tactics

    ERIC Educational Resources Information Center

    Tetlow, Linda

    2009-01-01

    Display took a wide variety of forms ranging from students presenting their initial planning and thought processes, to displays of their finished work, and their suggestions for extending the task should they, or others, have time to return to it in the future. A variety of different media were used from traditional posters in many shapes and…

  2. Mounted drilling apparatus

    SciTech Connect

    Manten, H.

    1982-07-20

    The drilling apparatus includes a mount in the form of a cylindrical member defining an elongated passageway and being provided with two opposite guiding rails each being formed with an elongated recessed channel communicating with the passageway; a rotary drive for holding a drill rod has a non-rotating casing provided with guiding elements movable in the recesses of the guiding rails; a feeding mechanism for advancing the rotary drive includes either tooth racks arranged in the recesses of the guiding rails and driving pinions mounted on the casing of the rotary drive or cylinder and piston units located in the recesses of the guide rails and cooperating with feed cables or chains. The mount is supported on a mobile undercarriage which is provided with two pairs of vertically adjustable supporting legs.

  3. MOUNT BALDY WILDERNESS, ARIZONA.

    USGS Publications Warehouse

    Finnell, Tommy L.; Soule, John H.

    1984-01-01

    The Mount Baldy Wilderness, Arizona, was surveyed for mineral resources and was judged to have little or no promise for the occurrence of mineral resources. No mineral deposits, mining claims, or concentrations of trace metals were recognized within the area. No oil test holes have been drilled within the area; holes drilled about 35 mi north of the area were not productive. Further study of the Mount Baldy Wilderness would seem warranted only in the event that economic deposits of minerals or petroleum are found in nearby areas.

  4. Evaluation of display and control concepts for a terminal configured vehicle in final approach in a windshear environment

    NASA Technical Reports Server (NTRS)

    Levison, W. H.

    1978-01-01

    A revised treatment of nonrandom inputs was incorporated in the model. Response behavior was observed for two display configurations (a pictorial EADI presentation and a flight-director configuration requiring use of a panel-mounted airspeed indicator), two control configurations (attitude and velocity control wheel steering), and two shear environments, each of which contained a head-to-tail shear and a vertical component. In general, performance trends predicted by the model were confirmed experimentally. Experimental and analytical results both indicated superiority to the EADI display with respect to regulation of height and airspeed errors. Velocity steering allowed tighter regulation of height errors, but control parameters had little influence on airspeed regulation. Model analysis indicated that display-related differences could be ascribed to differences in the quality of speed-related information provided by the two displays.

  5. Helmet-Mounted Displays: Sensation, Perception and Cognition Issues

    DTIC Science & Technology

    2009-01-01

    256 Peripheral Vision... peripheral vision (i.e., tunnel vision) and a loss of color perception and scene contrast but no loss of consciousness. The pilot still has auditory...into the instantaneous FOV of the subject, providing a higher performance system. Special techniques such as foveal/ peripheral image generation and

  6. Apollo Telescope Mount Illustration

    NASA Technical Reports Server (NTRS)

    1972-01-01

    The Apollo Telescope Mount (ATM) served as the first marned astronomical observatory in space. It was designed for solar research from Earth orbit aboard the Skylab. This image is a cutaway illustration of the ATM canister with callouts and characteristics. The ATM was designed and developed by the Marshall Space Flight Center.

  7. Apollo Telescope Mount Illustration

    NASA Technical Reports Server (NTRS)

    1971-01-01

    The Apollo Telescope Mount (ATM) served as the first marned astronomical observatory in space. It was designed for solar research from Earth orbit aboard the Skylab. This image is a cutaway illustration of the ATM canister. The ATM was designed and developed by the Marshall Space Flight Center.

  8. Apollo Telescope Mount Illustration

    NASA Technical Reports Server (NTRS)

    1971-01-01

    The Apollo Telescope Mount (ATM) served as the first marned astronomical observatory in space. It was designed for solar research from Earth orbit aboard the Skylab. This image is a cutaway illustration of the ATM canister with callouts. The ATM was designed and developed by the Marshall Space Flight Center.

  9. Housing And Mounting Structure

    DOEpatents

    Anderson, Gene R.; Armendariz, Marcelino G.; Baca, Johnny R.F.; Bryan, Robert P.; Carson, Richard F.; Duckett, III, Edwin B.; McCormick, Frederick B.; Miller, Gregory V.; Peterson, David W.; Smith, Terrance T.

    2005-03-08

    This invention relates to an optical transmitter, receiver or transceiver module, and more particularly, to an apparatus for connecting a first optical connector to a second optical connector. The apparatus comprises: (1) a housing having at least a first end and at least a second end, the first end of the housing capable of receiving the first optical connector, and the second end of the housing capable of receiving the second optical connector; (2) a longitudinal cavity extending from the first end of the housing to the second end of the housing; and (3) an electromagnetic shield comprising at least a portion of the housing. This invention also relates to an apparatus for housing a flexible printed circuit board, and this apparatus comprises: (1) a mounting structure having at least a first surface and a second surface; (2) alignment ridges along the first and second surfaces of the mounting structure, the alignment ridges functioning to align and secure a flexible printed circuit board that is wrapped around and attached to the first and second surfaces of the mounting structure; and (3) a series of heat sink ridges adapted to the mounting structure, the heat sink ridges functioning to dissipate heat that is generated from the flexible printed circuit board.

  10. Vibrotactile Sensitivity of the Head

    DTIC Science & Technology

    2009-01-01

    tissue in the skull, via vibrators mounted on the head, which stimulates the cochlea (resulting in an auditory sensation) while bypassing the external...are compatible with the sensitivity of the user. The extent to which vibrotactile* stimulation of the head is viable as a method of communication...cycle fraction of 0.25, and three repetitions extending the stimulation period of the signal to 750 ms (figure 5). Furthermore, the signal was divided

  11. Scaling Robotic Displays: Displays and Techniques for Dismounted Movement with Robots

    DTIC Science & Technology

    2010-04-01

    improvements for the displays. They suggested a better system for preventing glare or washout with the HHD. Several suggested adding a better sunshield...at a 45° angle so the sun does not shine directly on it. For the HMD, they suggested a better mounting system was needed. Problems were...display area bigger. 2 Stiffer armature to prevent wobbling, better mounting system than the goggles, and a focusing feature to adjust diopters for

  12. Use of display technologies for augmented reality enhancement

    NASA Astrophysics Data System (ADS)

    Harding, Kevin

    2016-06-01

    Augmented reality (AR) is seen as an important tool for the future of user interfaces as well as training applications. An important application area for AR is expected to be in the digitization of training and worker instructions used in the Brilliant Factory environment. The transition of work instructions methods from printed pages in a book or taped to a machine to virtual simulations is a long step with many challenges along the way. A variety of augmented reality tools are being explored today for industrial applications that range from simple programmable projections in the work space to 3D displays and head mounted gear. This paper will review where some of these tool are today and some of the pros and cons being considered for the future worker environment.

  13. Head Lice

    MedlinePlus

    Head lice are parasitic wingless insects. They live on people's heads and feed on their blood. An adult louse ... Children ages 3-11 and their families get head lice most often. Personal hygiene has nothing to ...

  14. Head Lice

    MedlinePlus

    ... Schedules Nutrient Shortfall Questionnaire Home Diseases and Conditions Head Lice Head Lice Condition Family HealthKids and Teens Share Head Lice Table of Contents1. Overview2. Symptoms3. Causes4. Prevention5. ...

  15. Suppression of biodynamic interference in head-tracked teleoperation

    NASA Technical Reports Server (NTRS)

    Lifshitz, S.; Merhav, S. J.; Grunwald, A. J.; Tucker, G. E.; Tischler, M. B.

    1991-01-01

    The utility of helmet-tracked sights to provide pointing commands for teleoperation of cameras, lasers, or antennas in aircraft is degraded by the presence of uncommanded, involuntary heat motion, referred to as biodynamic interference. This interference limits the achievable precision required in pointing tasks. The noise contributions due to biodynamic interference consists of an additive component which is correlated with aircraft vibration and an uncorrelated, nonadditive component, referred to as remnant. An experimental simulation study is described which investigated the improvements achievable in pointing and tracking precision using dynamic display shifting in the helmet-mounted display. The experiment was conducted in a six degree of freedom motion base simulator with an emulated helmet-mounted display. Highly experienced pilot subjects performed precision head-pointing tasks while manually flying a visual flight-path tracking task. Four schemes using adaptive and low-pass filtering of the head motion were evaluated to determine their effects on task performance and pilot workload in the presence of whole-body vibration characteristic of helicopter flight. The results indicate that, for tracking tasks involving continuously moving targets, improvements of up to 70 percent can be achieved in percent on-target dwelling time and of up to 35 percent in rms tracking error, with the adaptive plus low-pass filter configuration. The results with the same filter configuration for the task of capturing randomly-positioned, stationary targets show an increase of up to 340 percent in the number of targets captured and an improvement of up to 24 percent in the average capture time. The adaptive plus low-pass filter combination was considered to exhibit the best overall display dynamics by each of the subjects.

  16. An evaluation of flight path formats head-up and head-down

    NASA Technical Reports Server (NTRS)

    Sexton, George A.; Moody, Laura E.; Evans, Joanne; Williams, Kenneth E.

    1988-01-01

    Flight path primary flight display formats were incorporated on head-up and head-down electronic displays and integrated into an Advanced Concepts Flight Simulator. Objective and subjective data were collected while ten airline pilots evaluated the formats by flying an approach and landing task under various ceiling, visibility and wind conditions. Deviations from referenced/commanded airspeed, horizontal track, vertical track and touchdown point were smaller using the head-up display (HUD) format than the head-down display (HDD) format, but not significantly smaller. Subjectively, the pilots overwhelmingly preferred (1) flight path formats over attitude formats used in current aircraft, and (2) the head-up presentation over the head-down, primarily because it eliminated the head-down to head-up transition during low visibility landing approaches. This report describes the simulator, the flight displays, the format evaluation, and the results of the objective and subjective data.

  17. Voluntary presetting of the vestibular ocular reflex permits gaze stabilization despite perturbation of fast head movements

    NASA Technical Reports Server (NTRS)

    Zangemeister, Wolfgang H.

    1989-01-01

    Normal subjects are able to change voluntarily and continuously their head-eye latency together with their compensatory eye movement gain. A continuous spectrum of intent-latency modes of the subject's coordinated gaze through verbal feedback could be demonstrated. It was also demonstrated that the intent to counteract any perturbation of head-eye movement, i.e., the mental set, permitted the subjects to manipulate consciously their vestibular ocular reflex (VOR) gain. From the data, it is inferred that the VOR is always on. It may be, however, variably suppressed by higher cortical control. With appropriate training, head-mounted displays should permit an easy VOR presetting that leads to image stabilization, perhaps together with a decrease of possible misjudgements.

  18. Mount Erebus activity

    NASA Astrophysics Data System (ADS)

    An international team of scientists reports that unusually high seismic activity joggled Mount Erebus last fall. However, the Antarctic volcano showed no external signs of an eruption.When scientists from the United States, Japan, and New Zealand returned to the world's southernmost active volcano last November for their annual field expedition, they found that seismic stations recorded 650 small tremors on October 8; prior to that, the number of quakes had averaged between 20 and 80 per day. The October 8 maximum was followed by 140 on October 9 and 120 on October 10. Philip R. Kyle, assistant professor of geochemistry at the New Mexico Institute of Mining and Technology in Socorro and leader of the team studying Mount Erebus, noted that some of the strongest earthquakes recorded during the team's 3 years of observations occurred on October 8; these registered less than 2 on the Richter scale.

  19. Mount Wilson Observatory

    NASA Astrophysics Data System (ADS)

    Murdin, P.

    2000-11-01

    Mount Wilson Observatory, located in the San Gabriel Mountains near Pasadena, California, was founded in 1904 by George Ellery Hale with financial support from Andrew Carnegie. In the 1920s and 1930s, working at the 2.5 m Hooker telescope, Edwin Hubble made two of the most important discoveries in the history of astronomy: first, that `nebulae' are actually island universes—galaxies—each with bil...

  20. Thread-Mounted Thermocouple

    NASA Technical Reports Server (NTRS)

    Ward, Stanley W.

    1988-01-01

    Thread-mounted thermocouple developed to accurately measure temperature of surrounding material. Comprised of threaded rod or bolt drilled along length, dual-hole ceramic insulator rod, thermocouple wire, optional ceramic filler, and epoxy resin. In contact with and takes average temperature of, surrounding material. Fabricated easily in size and metal to suit particular application. Because of simplicity and ability to measure average temperature, widespread use of design foreseen in varity of applications.

  1. Plasma displays

    SciTech Connect

    Sobel, A.

    1991-12-01

    Plasma displays make use of lightly ionized glow discharges to produce light, perform switching and selection functions, or both. Both the negative glow and the positive column are used. Color can be attained by using UV from the discharge to stimulate phosphors. The adroit use of priming can reduce the number of drive circuits required - an advantage unique in the display art to plasma devices. Short voltage pulses can improve the efficacy of positive-column devices. Short voltage pulses can improve the efficacy of positive-column devices. The gas discharge can be used as a source of electrons, which can then excite cathodoluminescent phosphors in a variety of colors. It can also be used as a selection means for liquid-crystal displays. In this paper a wide variety of device configurations, using both unidirectional and bidirectional pulse excitations, is described.

  2. Solar panel mounting assembly

    SciTech Connect

    Eiden, G.E.

    1990-01-02

    This patent describes a mounting assembly for pivotally connecting a solar panel or collector to a base. The mounting assembly comprising: a frame whereupon the solar panel or collector can be mounted; a first plate connected to the frame, the plate having a pivot hole and a plurality of angle displacement holes each being equidistant from the pivot hole; a second plate connected to the base and situated substantially parallel to the first plate. The second plate having a pivot hole and an angle displacement hole being situated substantially the same distance apart from the second plate pivot hole as the distance between the pivot and displacement holes of the first plate; a pivot shaft received through the plate pivot hole and the second plate pivot hole whereby the frame and first plate can pivot with respect to the second plate and the base; an angle displacement shaft selectively received through the second plate angle displacement hole and any one of the first plate angle displacement holes whereby the frame and first plate can be selectively angularly fixed with respect to the second plate and the base; a U-member having two legs, the second plate being connected to the U-member; and, a selectively rotable shaft.

  3. Monitoring Mount Baker Volcano

    USGS Publications Warehouse

    Malone, S.D.; Frank, D.

    1976-01-01

    Hisotrically active volcanoes in the conterminous United States are restricted to the Cascade Range and extend to the Cascade Range and extend from Mount Baker near the Canadian border to Lassen Peak in northern California. Since 1800 A.D, most eruptive activity has been on a relatively small scale and has not caused loss of life or significant property damage. However, future  volcanism predictably will have more serious effects because of greatly increased use of land near volcanoes during the present century. (See "Appraising Volcanic Hazards of the Cascade Range of the Northwestern United States," Earthquake Inf. Bull., Sept.-Oct. 1974.) The recognition an impending eruption is highly important in order to minimize the potential hazard to people and property. Thus, a substantial increase in hydrothermal activity at Mount Baker in March 1975 ( see "Mount Baker Heating Up," July-Aug. 1975 issue) was regarded as a possible first signal that an eruption might occur, and an intensive monitoring program was undertaken. 

  4. Performance Effects of Mounting a Helmet-Mounted Display on the ANVIS Mount of the HGU-56P Helmet (Reprint)

    DTIC Science & Technology

    2006-09-01

    on the Microvision , Inc., Redmond, Washington, Spectrum SD2500 HMD. The SD2500 is a monocular, full-color, scanning laser HMD.5 Figure 1. Front...contributing equally) with a contrast ratio of 33. This contrast ratio was derived from a recent evaluation of the Microvision , Inc., Virtual...portion of the spectrum. 0.0 0.2 0.4 0.6 0.8 1.0 380 430 480 530 580 630 680 730 780 Wavelength (nm) R el at iv e lu m in an ce Figure 3

  5. 62. SIXTEEN INCH GUN MOUNTED ON THE MACHINING LATHE; LOOKING ...

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

    62. SIXTEEN INCH GUN MOUNTED ON THE MACHINING LATHE; LOOKING WSW. THE GUN ITSELF EXTENDS BEYOND THE BRICK ARCHES OF THE MAIN SHOP FLOOR'S W WALL AND INTO THE W AISLE. THE LATHE'S CUTTING HEAD CAN BE SEEN AT THE RIGHT CENTER OF THE VIEW. (Ryan) - Watervliet Arsenal, Building No. 110, Hagner Road between Schull & Whittemore Roads, Watervliet, Albany County, NY

  6. Evaluating the Impact of Head Rotation Amplification on Virtual Reality Training Effectiveness

    SciTech Connect

    Ragan, Eric D; Bowman, Doug A; Scerbo, Siroberto; Bacim, Felipe

    2013-01-01

    Virtual reality (VR) systems have been proposed for use in numerous training scenarios, such as room clearing, which require the trainee to maintain spatial awareness. But many VR training systems lack a fully surrounding display, requiring trainees to use a combination of physical and virtual turns to view the environment, thus decreasing spatial awareness. One solution to this problem is to amplify head rotations, such that smaller physical turns are mapped to larger virtual turns, allowing trainees to view the surrounding environment with head movements alone. For example, in a multi-monitor system covering only a 90-degree field of regard, head rotations could be amplified four times to allow the user to see the entire 360-degree surrounding environment. This solution is attractive because it can be used with lower-cost VR systems and does not require virtual turning. However, the effects of amplified head rotations on spatial awareness and training transfer are not well understood. We hypothesized that small amounts of amplification might be tolerable, but that larger amplifications might cause trainees to become disoriented and to have decreased task performance and training transfer. In this paper, we will present our findings from an experiment designed to investigate these hypotheses. The experiment placed users in a virtual warehouse and asked them to move from room to room, counting objects placed around them in space. We varied the amount of amplification applied during these trials, and also varied the type of display used (head-mounted display or CAVE). We measured task performance and spatial awareness. We then assessed training transfer in an assessment environment with a fully surrounding display and no amplification. The results of this study will inform VR training system developers about the potential negative effects of using head rotation amplification and contribute to more effective VR training system design.

  7. Perceiving a stable world during active rotational and translational head movements.

    PubMed

    Jaekl, P M; Jenkin, M R; Harris, Laurence R

    2005-06-01

    When a person moves through the world, the associated visual displacement of the environment in the opposite direction is not usually seen as external movement but rather as a changing view of a stable world. We measured the amount of visual motion that can be tolerated as compatible with the perception of moving within a stable world during active, sinusoidal, translational and rotational head movement. Head movements were monitored by means of a low-latency, mechanical head tracker and the information was used to update a helmet-mounted visual display. A variable gain was introduced between the head tracker and the display. Ten subjects adjusted this gain until the visual display appeared stable during sinusoidal yaw, pitch and roll head rotations and naso-occipital, inter-aural and dorso-ventral translations at 0.5 Hz. Each head movement was tested with movement either orthogonal to or parallel with gravity. A wide spread of gains was accepted as stable (0.8 to 1.4 for rotation and 1.1 to 1.8 for translation). The gain most likely to be perceived as stable was greater than that required by the geometry (1.2 for rotation; 1.4 for translation). For rotational motion, the mean gains were the same for all axes. For translation there was no effect of whether the movement was inter-aural (mean gain 1.6) or dorso-ventral (mean gain 1.5) and no effect of the relative orientation of the translation direction relative to gravity. However translation in the naso-occipital direction was associated with more closely veridical settings (mean gain 1.1) and narrower standard deviations than in other directions. These findings are discussed in terms of visual and non-visual contributions to the perception of an earth-stable environment during active head movement.

  8. Perceptual stability during active head movements orthogonal and parallel to gravity.

    PubMed

    Jaekl, P; Jenkin, M; Harris, L R

    2003-01-01

    We measured how much the visual world could be moved during various head rotations and translations and still be perceived as visually stable. Using this as a monitor of how well subjects know about their own movement, we compared performance in different directions relative to gravity. For head rotations, we compared the range of visual motion judged compatible with a stable environment while rotating around an axis orthogonal to gravity (where rotation created a rotating gravity vector across the otolith macula), with judgements made when rotation was around an earth-vertical axis. For translations, we compared the corresponding range of visual motion when translation was parallel to gravity (when imposed accelerations added to or subtracted from gravity), with translations orthogonal to gravity. Ten subjects wore a head-mounted display and made active head movements at 0.5 Hz that were monitored by a low-latency mechanical tracker. Subjects adjusted the ratio between head and image motion until the display appeared perceptually stable. For neither rotation nor translation were there any differences in judgements of perceptual stability that depended on the direction of the movement with respect to the direction of gravity.

  9. Perception de la verticale avec Un cadre visuel solidaire de la tete: implications pour la conception des afficheurs de casques en ae’ronauflque (Perception of the Vertical With a Head-Mounted Visual Frame: Implication for the Design of Helmet-Mounted Displays in Aeronautics)

    DTIC Science & Technology

    2003-02-01

    leurs changements d’orientation. L’orientation du cadre solidaire de la tete ne peut etre 6valude que sur la base des signaux de position de la tete...r6fdrentiel c6phalocentr6 sont inexistantes. Au contraire, lorsque lorientation du cadre est dissoci6e de celle de la tete, toute rotation peut etre ...rapport it la tete peuvent etre prises en compte en conjonction avec les signaux vestibulaires et proprioceptifs qui renseignent sur lorientation de la

  10. The Mount Wilson magnetograph

    NASA Technical Reports Server (NTRS)

    Howard, R.; Boyden, J. E.; Bruning, D. H.; Clark, M. K.; Crist, H. W.; Labonte, B. J.

    1983-01-01

    In the summer of 1957, an instrument quite similar to the prototype solar magnetograph described by Babcock (1953) was installed at the 150-foot tower telescope at the Mount Wilson Observatory, and daily magnetograph observations of the full disk of the sun were started. During the following years, the instrument was modified and improved on several occasions. The present investigation is concerned with the present state of the magnetograph, which was largely rebuilt during 1981. Attention is given to the spectrograph entrance slit, the diffraction grating, the exit slit, the employed microprocessor, the setup procedure, the magnetic signal, the Doppler signal, and a solar magnetogram.

  11. MOUNT WASHINGTON WILDERNESS, OREGON.

    USGS Publications Warehouse

    Taylor, Edward M.; Causey, J. Douglas

    1984-01-01

    On the basis of a mineral survey, Mount Washington Wilderness, Oregon has little promise for the occurrence of metallic mineral or fossil fuel resources. Abundant cinder resources occur in the wilderness, but other large volume cinder deposits are available outside the wilderness and closer to markets. Analysis of the geothermal potential of the High Cascades province cannot be made without data on the subsurface thermal and hydrologic regimes which can only be provided by deep drill holes. Several deep holes could be drilled in areas outside the wildernesses of the High Cascades, from which extrapolations of the geothermal potential of the wildernesses could be made.

  12. Rebuilding Mount St. Helens

    USGS Publications Warehouse

    Schilling, Steve P.; Ramsey, David W.; Messerich, James A.; Thompson, Ren A.

    2006-01-01

    On May 18, 1980, Mount St. Helens, Washington exploded in a spectacular and devastating eruption that shocked the world. The eruption, one of the most powerful in the history of the United States, removed 2.7 cubic kilometers of rock from the volcano's edifice, the bulk of which had been constructed by nearly 4,000 years of lava-dome-building eruptions. In seconds, the mountain's summit elevation was lowered from 2,950 meters to 2,549 meters, leaving a north-facing, horseshoe-shaped crater over 2 kilometers wide. Following the 1980 eruption, Mount St. Helens remained active. A large lava dome began episodically extruding in the center of the volcano's empty crater. This dome-building eruption lasted until 1986 and added about 80 million cubic meters of rock to the volcano. During the two decades following the May 18, 1980 eruption, Crater Glacier formed tongues of ice around the east and west sides of the lava dome in the deeply shaded niche between the lava dome and the south crater wall. Long the most active volcano in the Cascade Range with a complex 300,000-year history, Mount St. Helens erupted again in the fall of 2004 as a new period of dome building began within the 1980 crater. Between October 2004 and February 2006, about 80 million cubic meters of dacite lava erupted immediately south of the 1980-86 lava dome. The erupting lava separated the glacier into two parts, first squeezing the east arm of the glacier against the east crater wall and then causing equally spectacular crevassing and broad uplift of the glacier's west arm. Vertical aerial photographs document dome growth and glacier deformation. These photographs enabled photogrammetric construction of a series of high-resolution digital elevation models (DEMs) showing changes from October 4, 2004 to February 9, 2006. From the DEMs, Geographic Information Systems (GIS) applications were used to estimate extruded volumes and growth rates of the new lava dome. The DEMs were also used to quantify dome

  13. Flight experiment of pilot display for search-and-rescue helicopter

    NASA Astrophysics Data System (ADS)

    Funabiki, Kohei; Tsuda, Hiroka; Iijima, Tomoko; Nojima, Takuya; Tawada, Kazuho; Yoshida, Takashi

    2009-05-01

    JAXA (Japan Aerospace Exploration Agency), together with Shimadzu Corporation and NEC, has initiated a research project named SAVERH (Situation Awareness and Visual Enhancer for Rescue Helicopter) that aims at inventing method of presenting suitable pilot information to support helicopter search and rescue missions. As the initial stage of this research, a series of flight experiments was conducted to investigate the feasibility of operations enhanced by an E/SVS (Enhanced / Synthetic Vision System) and to clarify system issues. An integrated system comprising an HMD (Helmet Mounted Display) and a FLIR (Forward Looking Infrared) sensor were installed in a JAXA research helicopter, and Tunnel-in-the-Sky symbology and a Synthetic Terrain image combined with the FLIR image were presented on the HMD and/or on a Head Down Display (HDD). Through a total of 17 flights including night flights, the potential capability of the system was demonstrated while many issues for further investigation were identified.

  14. Restocking the optical designers' toolbox for next-generation wearable displays (Presentation Recording)

    NASA Astrophysics Data System (ADS)

    Kress, Bernard C.

    2015-09-01

    Three years ago, industry and consumers learned that there was more to Head Mounted Displays (HMDs) than the long-lasting but steady market for defense or the market for gadget video player headsets: the first versions of Smart Glasses were introduced to the public. Since then, most major consumer electronics companies unveiled their own versions of Connected Glasses, Smart Glasses or Smart Eyewear, AR (Augmented Reality) and VR (Virtual Reality) headsets. This rush resulted in the build-up of a formidable zoo of optical technologies, each claiming to be best suited for the task on hand. Today, the question is not so much anymore "will the Smart Glass market happen?" but rather "which optical technologies will be best fitted for the various declinations of the existing wearable display market," one of the main declination being the Smart Glasses market.

  15. Surface mount component jig

    DOEpatents

    Kronberg, James W.

    1990-08-07

    A device for bending and trimming the pins of a dual-inline-package component and the like for surface mounting rather than through mounting to a circuit board comprises, in a first part, in pin cutter astride a holder having a recess for holding the component, a first spring therebetween, and, in a second part, two flat members pivotally interconnected by a hinge and urged to an upward peaked position from a downward peaked position by a second spring. As a downward force is applied to the pin cutter it urges the holder downward, assisted by the first spring and a pair of ridges riding on shoulders of the holder, to carry the component against the upward peaked flat members which guide the pins outwardly. As the holder continues downwardly, the flat members pivot to the downward peaked position bending the pins upwardly against the sides of the holder. When the downward movement is met with sufficient resistance, the ridges of the pin cutter ride over the holder's shoulders to continue downward to cut any excess length of pin.

  16. Digital Holography Display (2)

    NASA Astrophysics Data System (ADS)

    Lee, Cheok Peng; Asundi, A.; Yu, Yang; Xiao, Zhen Zhong

    equipments and components can be easy line up and mounted in the compartment. 3) This solid 6 mm diameter fibre conduit is implemented to transmit the higher diffractive image, it is also the brightest and clearer image as compare to other lower order images. This means many of the lower order and blurred images would be neglected for display and consider as the energy lost.

  17. Updated defense display market assessment

    NASA Astrophysics Data System (ADS)

    Desjardins, Daniel D.; Hopper, Darrel G.

    1999-08-01

    This paper addresses the number, function and size of principal military displays and establishes a basis to determine the opportunities for technology insertion in the immediate future and into the next millennium. Principal military displays are defined as those occupying appreciable crewstation real-estate and/or those without which the platform could not carry out its intended mission. DoD 'office' applications are excluded from this study. The military displays market is specified by such parameters as active area and footprint size, and other characteristics such as luminance, gray scale, resolution, angle, color, video capability, and night vision imaging system compatibility. Funded, future acquisitions, planned and predicted crewstation modification kits, and form-fit upgrades are taken into account. This paper provides an overview of the DoD niche market, allowing both government and industry a necessary reference by which to meet DoD requirements for military displays in a timely and cost-effective manner. The aggregate DoD installed base for direct-view and large-area military displays is presently estimated to be in excess of 313,000. Miniature displays are those which must be magnified to be viewed, involve a significantly different manufacturing paradigm and are used in helmet mounted displays and thermal weapon sight applications. Some 114,000 miniature displays are presently included within future weapon system acquisition plans. For vendor production planning purposes it is noted that foreign military sales could substantially increase these quantities. The vanishing vendor syndrome (VVS) for older display technologies continues to be a growing, pervasive problem throughout DoD, which consequently must leverage the more modern, especially flat panel, display technologies being developed to replace older, especially cathode ray tube, technology for civil-commercial markets. Total DoD display needs (FPD, HMD) are some 427,000.

  18. Improvement of Head-Up Display Standards. Volume 1. Head-Up Display Design Guide. Appendix

    DTIC Science & Technology

    1987-09-01

    the angle between an aircraft longitudinal reference (FRL or ACPL) and the air velocity vector projected on the plane defined by the aircraft ...longitudinal axes. 11. ANGLE OF SIDESLIP (BETA): The angle of sideslip is the angle between the aircraft longitudinal reference (FRL or ACRL) and the air...velocity vector projected on the plane defined by the aircraft longitudinal reference and the aircraft lateral ax- is. BETA is the left-right equivalent of

  19. Head MRI

    MedlinePlus

    ... the head; MRI - cranial; NMR - cranial; Cranial MRI; Brain MRI; MRI - brain; MRI - head ... the test, tell your provider if you have: Brain aneurysm clips An artificial heart valves Heart defibrillator ...

  20. Head Injuries

    MedlinePlus

    ... scalp internal head injuries, which may involve the skull, the blood vessels within the skull, or the brain Fortunately, most childhood falls or ... knock the brain into the side of the skull or tear blood vessels. Some internal head injuries ...

  1. Heads Up

    MedlinePlus

    ... Us HEADS UP Apps Reshaping the Culture Around Concussion in Sports Get HEADS UP on Your Web Site Concussion ... fit, and maintain the right helmet for specific sports. Concussion Laws Learn about Return to Play and other ...

  2. Mount Vesuvius, Italy

    NASA Technical Reports Server (NTRS)

    2002-01-01

    This Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) image of Mt. Vesuvius, Italy was acquired September 26, 2000. The full-size false-color image covers an area of 36 by 45 km. Vesuvius overlooks the city of Naples and the Bay of Naples in central Italy. (Popocatepetl and Mount Fuji are other volcanos surrounded by dense urban areas.) In 79 AD, Vesuvius erupted cataclysmically, burying all of the surrounding cites with up to 30 m of ash. The towns of Pompeii and Herculanaeum were rediscovered in the 18th century, and excavated in the 20th century. They provide a snapshot of Roman life from 2000 years ago: perfectly preserved are wooden objects, food items, and the casts of hundreds of victims. Vesuvius is intensively monitored for potential signs of unrest that could signal the beginning of another eruption. Image courtesy NASA/GSFC/MITI/ERSDAC/JAROS, and U.S./Japan ASTER Science Team

  3. Head lice.

    PubMed

    Frankowski, Barbara L; Weiner, Leonard B

    2002-09-01

    Head lice infestation is associated with little morbidity but causes a high level of anxiety among parents of school-aged children. This statement attempts to clarify issues of diagnosis and treatment of head lice and makes recommendations for dealing with head lice in the school setting.

  4. Virtual acoustic displays

    NASA Technical Reports Server (NTRS)

    Wenzel, Elizabeth M.

    1991-01-01

    A 3D auditory display can potentially enhance information transfer by combining directional and iconic information in a quite naturalistic representation of dynamic objects in the interface. Another aspect of auditory spatial clues is that, in conjunction with other modalities, it can act as a potentiator of information in the display. For example, visual and auditory cues together can reinforce the information content of the display and provide a greater sense of presence or realism in a manner not readily achievable by either modality alone. This phenomenon will be particularly useful in telepresence applications, such as advanced teleconferencing environments, shared electronic workspaces, and monitoring telerobotic activities in remote or hazardous situations. Thus, the combination of direct spatial cues with good principles of iconic design could provide an extremely powerful and information-rich display which is also quite easy to use. An alternative approach, recently developed at ARC, generates externalized, 3D sound cues over headphones in realtime using digital signal processing. Here, the synthesis technique involves the digital generation of stimuli using Head-Related Transfer Functions (HRTF's) measured in the two ear-canals of individual subjects. Other similar approaches include an analog system developed by Loomis, et. al., (1990) and digital systems which make use of transforms derived from normative mannikins and simulations of room acoustics. Such an interface also requires the careful psychophysical evaluation of listener's ability to accurately localize the virtual or synthetic sound sources. From an applied standpoint, measurement of each potential listener's HRTF's may not be possible in practice. For experienced listeners, localization performance was only slightly degraded compared to a subject's inherent ability. Alternatively, even inexperienced listeners may be able to adapt to a particular set of HRTF's as long as they provide adequate

  5. Reality and Surreality of 3-D Displays: Holodeck and Beyond

    DTIC Science & Technology

    2000-01-01

    Holodeck is the reality that significantly better 3D display systems are possible. Keywords: true 3D displays, multiplexed 2D display ( autostereoscopic ...displays still do not use them in their own offices. Thus, 3D approaches that are autostereoscopic (that is, no-head gear is required) are preferred. A...challenges noted throughout the aforegoing sections of this paper will be steadily overcome. True 3D , autostereoscopic (no head gear) monitors with usable

  6. Mount Zion Cemetery, 1975 Plot Plan Mount Zion Cemetery/ ...

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

    Mount Zion Cemetery, 1975 Plot Plan - Mount Zion Cemetery/ Female Union Band Cemetery, Bounded by 27th Street right-of-way N.W. (formerly Lyons Mill Road), Q Street N.W., & Mill Road N.W., Washington, District of Columbia, DC

  7. Head stabilization shows visual and inertial dependence during passive stimulation: implications for virtual rehabilitation.

    PubMed

    Wright, W Geoffrey; Agah, Mobin Rastgar; Darvish, Kurosh; Keshner, Emily A

    2013-03-01

    Sensorimotor coordination relies on the fine calibration and integration of visual, vestibular, and somatosensory input. Using virtual environments (VE) allows for the dissociation of visual and inertial inputs to manipulate human behavioral outputs. Our goal was to employ VE technology in a novel manner to investigate how head stabilization is affected by spatiotemporal properties of dynamic visual input when combined with passive motion on a linear sled. Healthy adults (n = 12) wore a head-mounted display during naso-occipital sinusoidal horizontal whole body translations while seated. Subjects were secured in a seat with a five-point harness, with the head free to move. Frequency and amplitude of sinusoidal input (i.e., inertial conditions) were set to create overlapping conditions of maximum acceleration (amax) or velocity (vmax). Four inertial conditions were combined with four visual conditions (VIS). VIS were created so that direction of optic flow either matched direction of passive motion or did not. The effect of near and far fixation distance within the VE was also tested. Head kinematics were collected with a three-axis gyro. Head stability showed a complex interaction dependent on changes in weighting of visual and inertial inputs that changed with the sled driving frequency. Inertial condition affected amplitude (p < 0.0000) and phase (p < 0.0000) of head pitch angular velocity. In the absence of visual input, head pitch velocity amplitude increased (p < 0.01). An interaction effect between inertial and VIS conditions on head yaw occurred in SW (p < 0.05). There was also a significant interaction of depth of field and inertial condition on amplitude (p < 0.001) and phase (p < 0.05) of head yaw velocity in SW, especially during high vmax conditions. We conclude visual flow can organize lateral cervical responses despite being discordant with inertial input. When using VE for rehabilitation, possible unintended, involuntary or reflexive motor responses

  8. LED display for solo aircraft instrument navigation

    NASA Technical Reports Server (NTRS)

    Crouch, R. K.; Kelly, W. L., VI; Lina, L. J.; Meredith, B. D.

    1979-01-01

    Solo pilot's task is made easier through convenient display of landing and navigation data. Use of display shows promise as more efficient means of presenting sequential instructions and data, such as course heading, altitude, and radio frequency, to minimize pilot's workload during solo instrument flight.

  9. Augmenting digital displays with computation

    NASA Astrophysics Data System (ADS)

    Liu, Jing

    As we inevitably step deeper and deeper into a world connected via the Internet, more and more information will be exchanged digitally. Displays are the interface between digital information and each individual. Naturally, one fundamental goal of displays is to reproduce information as realistically as possible since humans still care a lot about what happens in the real world. Human eyes are the receiving end of such information exchange; therefore it is impossible to study displays without studying the human visual system. In fact, the design of displays is rather closely coupled with what human eyes are capable of perceiving. For example, we are less interested in building displays that emit light in the invisible spectrum. This dissertation explores how we can augment displays with computation, which takes both display hardware and the human visual system into consideration. Four novel projects on display technologies are included in this dissertation: First, we propose a software-based approach to driving multiview autostereoscopic displays. Our display algorithm can dynamically assign views to hardware display zones based on multiple observers' current head positions, substantially reducing crosstalk and stereo inversion. Second, we present a dense projector array that creates a seamless 3D viewing experience for multiple viewers. We smoothly interpolate the set of viewer heights and distances on a per-vertex basis across the arrays field of view, reducing image distortion, crosstalk, and artifacts from tracking errors. Third, we propose a method for high dynamic range display calibration that takes into account the variation of the chrominance error over luminance. We propose a data structure for enabling efficient representation and querying of the calibration function, which also allows user-guided balancing between memory consumption and the amount of computation. Fourth, we present user studies that demonstrate that the ˜ 60 Hz critical flicker fusion

  10. The Second Generation High Speed Rotor Head Mounted Instrumentation System

    NASA Technical Reports Server (NTRS)

    Lewis, John; Reynolds, R. S. (Technical Monitor)

    1997-01-01

    NASA Ames Research Center has been investigating the air pressure flow of a rotor blade on a UH-60 Black Hawk helicopter in-flight. This paper will address the changes and improvements due to additional restrictions and requirements for the instrumentation system. The second generation instrumentation system was substantially larger and this allowed greatly improved accessibility to the components for ease of maintenance as well as improved gain and offset adjustment capabilities and better filtering.

  11. 14. AERIAL VIEW OF ENGINE DISPLAY INSIDE PASSENGER CAR SHOP ...

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

    14. AERIAL VIEW OF ENGINE DISPLAY INSIDE PASSENGER CAR SHOP (NOW A TRANSPORTATION MUSEUM) - Baltimore & Ohio Railroad, Mount Clare Passenger Car Shop, Southwest corner of Pratt & Poppleton Streets, Baltimore, Independent City, MD

  12. Circular displays: control/display arrangements and stereotype strength with eight different display locations.

    PubMed

    Chan, Alan H S; Hoffmann, Errol R

    2015-01-01

    Two experiments are reported that were designed to investigate control/display arrangements having high stereotype strengths when using circular displays. Eight display locations relative to the operator and control were tested with rotational and translational controls situated on different planes according to the Frame of Reference Transformation Tool (FORT) model of Wickens et al. (2010). (Left. No, Right! Development of the Frame of Reference Transformation Tool (FORT), Proceedings of the Human Factors and Ergonomics Society 54th Annual Meeting, 54: 1022-1026). In many cases, there was little effect of display locations, indicating the importance of the Worringham and Beringer (1998. Directional stimulus-response compatibility: a test of three alternative principles. Ergonomics, 41(6), 864-880) Visual Field principle and an extension of this principle for rotary controls (Hoffmann and Chan (2013). The Worringham and Beringer 'visual field' principle for rotary controls. Ergonomics, 56(10), 1620-1624). The initial indicator position (12, 3, 6 and 9 o'clock) had a major effect on control/display stereotype strength for many of the six controls tested. Best display/control arrangements are listed for each of the different control types (rotational and translational) and for the planes on which they are mounted. Data have application where a circular display is used due to limited display panel space and applies to space-craft, robotics operators, hospital equipment and home appliances. Practitioner Summary: Circular displays are often used when there is limited space available on a control panel. Display/control arrangements having high stereotype strength are listed for four initial indicator positions. These arrangements are best for design purposes.

  13. Military Display Market: Fourth Comprehensive Edition

    DTIC Science & Technology

    2006-02-01

    acceleration up to 6g for 1 minute, and operate without degradation when subjected to the vibration environment of the various helicopters for which it...Helmet-Mounted Displays (HMD) and Night Vision Goggles ( NVG ), are in excess of 224,000. Of these, some 17,700 are miniature displays, either CRT...have significantly impacted future budgets: The DOD U.S. Global Defense Posture Review and the 2005 Base Realignment and Closure (BRAG) Commission

  14. Mount St. Helens Flyover

    NASA Technical Reports Server (NTRS)

    2002-01-01

    This Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) image of Mt. St. Helens volcano in Washington State was acquired on August 8, 2000 and covers an area of 37 by 51 km. Mount Saint Helens, a volcano in the Cascade Range of southwestern Washington that had been dormant since 1857, began to show signs of renewed activity in early 1980. On 18 May 1980, it erupted with such violence that the top of the mountain was blown off, spewing a cloud of ash and gases that rose to an altitude of 19 kilometers. The blast killed about 60 people and destroyed all life in an area of some 180 square kilometers (some 70 square miles), while a much larger area was covered with ash and debris. It continues to spit forth ash and steam intermittently. As a result of the eruption, the mountain's elevation decreased from 2,950 meters to 2,549 meters. The simulated fly-over was produced by draping ASTER visible and near infrared image data over a digital topography model, created from ASTER's 3-D stereo bands. The color was computer enhanced to create a 'natural' color image, where the vegetation appears green. The topography has been exaggerated 2 times to enhance the appearance of the relief. Landsat7 aquired an image of Mt. St. Helens on August 22, 1999. Image and animation courtesy NASA/GSFC/MITI/ERSDAC/JAROS, and U.S./Japan ASTER Science Team.

  15. Vetronics Technology Demonstrator Display Technology

    DTIC Science & Technology

    2007-11-02

    Private Computing Devices CanadaA GENERAL DYNAMICS COMPANY Display Architecture Video Module •General Purpose Video I/F • LVDS •RGB Analog •Separate...Hsync & Vsync •Composite TTL Sync •Sync on Green (RS-170) •NTSC/PAL/SECAM •Frame rate/Scan converter/Scaler •Standard LVDS output Power Supply Module...Mil-Std-1275 compliant input •Heater Power @ 150W LCD Display Head •Backlight •Microcontroller •Video I/F ( LVDS ) •Adapted for each specific LCD •8.4

  16. Head Injuries

    MedlinePlus

    ... injury, cerebral contusion, cerebral laceration, coma, head trauma, hematoma, impaired consciousness, postconcussion syndrome, skull fracture, skull penetration, stupor, vegetative state Family Health, Infants ...

  17. Mount Rainier National Park

    USGS Publications Warehouse

    Hoffman, Robert; Woodward, Andrea; Haggerty, Patricia K.; Jenkins, Kurt J.; Griffin, Paul C.; Adams, Michael J.; Hagar, Joan; Cummings, Tonnie; Duriscoe, Dan; Kopper, Karen; Riedel, Jon; Samora, Barbara; Marin, Lelaina; Mauger, Guillaume S.; Bumbaco, Karen; Littell, Jeremy S.

    2014-01-01

    Natural Resource Condition Assessments (NRCAs) evaluate current conditions for a subset of natural resources and resource indicators in national parks. NRCAs also report on trends in resource condition (when possible), identify critical data gaps, and characterize a general level of confidence for study findings. The resources and indicators emphasized in a given project depend on the park’s resource setting, status of resource stewardship planning and science in identifying high-priority indicators, and availability of data and expertise to assess current conditions for a variety of potential study resources and indicators. Although the primary objective of NRCAs is to report on current conditions relative to logical forms of reference conditions and values, NRCAs also report on trends, when appropriate (i.e., when the underlying data and methods support such reporting), as well as influences on resource conditions. These influences may include past activities or conditions that provide a helpful context for understanding current conditions and present-day threats and stressors that are best interpreted at park, watershed, or landscape scales (though NRCAs do not report on condition status for land areas and natural resources beyond park boundaries). Intensive cause-andeffect analyses of threats and stressors, and development of detailed treatment options, are outside the scope of NRCAs. It is also important to note that NRCAs do not address resources that lack sufficient data for assessment. For Mount Rainier National Park, this includes most invertebrate species and many other animal species that are subject to significant stressors from climate change and other anthropogenic sources such as air pollutants and recreational use. In addition, we did not include an analysis of the physical hydrology associated with streams (such as riverine landforms, erosion and aggradation which is significant in MORA streams), due to a loss of staff expertise from the USGS

  18. Mount St. Helens

    NASA Technical Reports Server (NTRS)

    2005-01-01

    This Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) image of Mount St. Helens was captured one week after the March 8, 2005, ash and steam eruption, the latest activity since the volcano's reawakening in September 2004. The new lava dome in the southeast part of the crater is clearly visible, highlighted by red areas where ASTER's infrared channels detected hot spots from incandescent lava. The new lava dome is 155 meters (500 feet) higher than the old lava dome, and still growing.

    With its 14 spectral bands from the visible to the thermal infrared wavelength region, and its high spatial resolution of 15 to 90 meters (about 50 to 300 feet), ASTER images Earth to map and monitor the changing surface of our planet.

    ASTER is one of five Earth-observing instruments launched December 18, 1999, on NASA's Terra satellite. The instrument was built by Japan's Ministry of Economy, Trade and Industry. A joint U.S./Japan science team is responsible for validation and calibration of the instrument and the data products.

    The broad spectral coverage and high spectral resolution of ASTER provides scientists in numerous disciplines with critical information for surface mapping, and monitoring of dynamic conditions and temporal change. Example applications are: monitoring glacial advances and retreats; monitoring potentially active volcanoes; identifying crop stress; determining cloud morphology and physical properties; wetlands evaluation; thermal pollution monitoring; coral reef degradation; surface temperature mapping of soils and geology; and measuring surface heat balance.

    The U.S. science team is located at NASA's Jet Propulsion Laboratory, Pasadena, Calif. The Terra mission is part of NASA's Science Mission Directorate.

    Size: 21.9 by 24.4 kilometers (13.6 by 15.1 miles) Location: 46.2 degrees North latitude, 122.2 degrees West longitude Orientation: North at top Image Data: ASTER bands 8, 3, and 1 Original Data Resolution

  19. Retired NASA F-18 being mounted on pedestal mount at Lancaster California Municipal Baseball Stadium

    NASA Technical Reports Server (NTRS)

    1997-01-01

    While workers on the ground steady the craft with guy ropes, workers atop a high-lift truck align the mounting plates as an F/A-18 Hornet airplane formerly flown by NASA's Dryden Flight Research Center is mounted on a 28-foot-tall pedestal in front of the municipal baseball stadium in the city of Lancaster, California. The aircraft was loaned to the city for pulbic display after its recent retirement by Dryden, which is located at nearby Edwards, California. The blue-and-white twin-jet aircraft was flown as a safety chase and support aircraft by NASA Dryden for about nine years before being retired. Known as 'The Hangar,' the stadium is the home field of the Lancaster Jethawks, a Class-A farm team of the Seattle Mariners.

  20. Adjustable Optical Mount Is More Rigid

    NASA Technical Reports Server (NTRS)

    Asbury, Bill G.; Coombs, David S.; Jones, Irby W.; Moore, Alvah S., Jr.

    1994-01-01

    Improved mount for lens or mirror in laser offers rigidity similar to that of nonadjustable optical mount. In comparison with older adjustable optical mounts, this one less susceptible to movements and distortions caused by vibrations and by thermal expansions and contractions. Mount contains neither adjustment rods (which grow or shrink as temperature varies) nor springs (which transmit vibrations to mounted optic).

  1. Detector Mount Design for IGRINS

    NASA Astrophysics Data System (ADS)

    Oh, Jae Sok; Park, Chan; Cha, Sang-Mok; Yuk, In-Soo; Park, Kwijong; Kim, Kang-Min; Chun, Moo-Young; Ko, Kyeongyeon; Oh, Heeyoung; Jeong, Ueejeong; Nah, Jakyoung; Lee, Hanshin; Jaffe, Daniel T.

    2014-06-01

    The Immersion Grating Infrared Spectrometer (IGRINS) is a near-infrared wide-band high-resolution spectrograph jointly developed by the Korea Astronomy and Space Science Institute and the University of Texas at Austin. IGRINS employs three HAWAII-2RG Focal Plane Array (H2RG FPA) detectors. We present the design and fabrication of the detector mount for the H2RG detector. The detector mount consists of a detector housing, an ASIC housing, a Field Flattener Lens (FFL) mount, and a support base frame. The detector and the ASIC housing should be kept at 65 K and the support base frame at 130 K. Therefore they are thermally isolated by the support made of GFRP material. The detector mount is designed so that it has features of fine adjusting the position of the detector surface in the optical axis and of fine adjusting yaw and pitch angles in order to utilize as an optical system alignment compensator. We optimized the structural stability and thermal characteristics of the mount design using computer-aided 3D modeling and finite element analysis. Based on the structural and thermal analysis, the designed detector mount meets an optical stability tolerance and system thermal requirements. Actual detector mount fabricated based on the design has been installed into the IGRINS cryostat and successfully passed a vacuum test and a cold test.

  2. Comparing the effectiveness of different displays in enhancing illusions of self-movement (vection).

    PubMed

    Riecke, Bernhard E; Jordan, Jacqueline D

    2015-01-01

    Illusions of self-movement (vection) can be used in virtual reality (VR) and other applications to give users the embodied sensation that they are moving when physical movement is unfeasible or too costly. Whereas a large body of vection literature studied how various parameters of the presented visual stimulus affect vection, little is known how different display types might affect vection. As a step toward addressing this gap, we conducted three experiments to compare vection and usability parameters between commonly used VR displays, ranging from stereoscopic projection and 3D TV to high-end head-mounted display (HMD, NVIS SX111) and recent low-cost HMD (Oculus Rift). The last experiment also compared these two HMDs in their native full field of view (FOV) and a reduced, matched FOV of 72° × 45°. Participants moved along linear and curvilinear paths in the virtual environment, reported vection onset time, and rated vection intensity at the end of each trial. In addition, user ratings on immersion, motion sickness, vection, and overall preference were recorded retrospectively and compared between displays. Unexpectedly, there were no significant effects of display on vection measures. Reducing the FOV for the HMDs (from full to 72° × 45°) decreased vection onset latencies, but did not affect vection intensity. As predicted, curvilinear paths yielded earlier and more intense vection. Although vection has often been proposed to predict or even cause motion sickness, we observed no correlation for any of the displays studied. In conclusion, perceived self-motion and other user experience measures proved surprisingly tolerant toward changes in display type as long as the FOV was roughly matched. This suggests that display choice for vection research and VR applications can be largely based on other considerations as long as the provided FOV is sufficiently large.

  3. Comparing the effectiveness of different displays in enhancing illusions of self-movement (vection)

    PubMed Central

    Riecke, Bernhard E.; Jordan, Jacqueline D.

    2015-01-01

    Illusions of self-movement (vection) can be used in virtual reality (VR) and other applications to give users the embodied sensation that they are moving when physical movement is unfeasible or too costly. Whereas a large body of vection literature studied how various parameters of the presented visual stimulus affect vection, little is known how different display types might affect vection. As a step toward addressing this gap, we conducted three experiments to compare vection and usability parameters between commonly used VR displays, ranging from stereoscopic projection and 3D TV to high-end head-mounted display (HMD, NVIS SX111) and recent low-cost HMD (Oculus Rift). The last experiment also compared these two HMDs in their native full field of view (FOV) and a reduced, matched FOV of 72° × 45°. Participants moved along linear and curvilinear paths in the virtual environment, reported vection onset time, and rated vection intensity at the end of each trial. In addition, user ratings on immersion, motion sickness, vection, and overall preference were recorded retrospectively and compared between displays. Unexpectedly, there were no significant effects of display on vection measures. Reducing the FOV for the HMDs (from full to 72° × 45°) decreased vection onset latencies, but did not affect vection intensity. As predicted, curvilinear paths yielded earlier and more intense vection. Although vection has often been proposed to predict or even cause motion sickness, we observed no correlation for any of the displays studied. In conclusion, perceived self-motion and other user experience measures proved surprisingly tolerant toward changes in display type as long as the FOV was roughly matched. This suggests that display choice for vection research and VR applications can be largely based on other considerations as long as the provided FOV is sufficiently large. PMID:26082735

  4. Apollo Telescope Mount Spar Assembly

    NASA Technical Reports Server (NTRS)

    1969-01-01

    The Apollo Telescope Mount (ATM), designed and developed by the Marshall Space Flight Center, served as the primary scientific instrument unit aboard the Skylab. The ATM contained eight complex astronomical instruments designed to observe the Sun over a wide spectrum from visible light to x-rays. This image shows the ATM spar assembly. All solar telescopes, the fine Sun sensors, and some auxiliary systems are mounted on the spar, a cruciform lightweight perforated metal mounting panel that divides the 10-foot long canister lengthwise into four equal compartments. The spar assembly was nested inside a cylindrical canister that fit into the rack, a complex frame, and was protected by the solar shield.

  5. SXI prototype mirror mount

    NASA Astrophysics Data System (ADS)

    1995-04-01

    The purpose of this contract was to provide optomechanical engineering and fabrication support to the Solar X-ray Imager (SXI) program in the areas of mirror, optical bench and camera assemblies of the telescope. The Center for Applied Optics (CAO) worked closely with the Optics and S&E technical staff of MSFC to develop and investigate the most viable and economical options for the design and fabrication of a number of parts for the various telescope assemblies. All the tasks under this delivery order have been successfully completed within budget and schedule. A number of development hardware parts have been designed and fabricated jointly by MSFC and UAH for the engineering model of SXI. The major parts include a nickel electroformed mirror and a mirror mount, plating and coating of the ceramic spacers, and gold plating of the contact rings and fingers for the camera assembly. An aluminum model of the high accuracy sun sensor (HASS) was also designed and fabricated. A number of fiber optic tapers for the camera assembly were also coated with indium tin oxide and phosphor for testing and evaluation by MSFC. A large number of the SXI optical bench parts were also redesigned and simplified for a prototype telescope. These parts include the forward and rear support flanges, front aperture plate, the graphite epoxy optical bench and a test fixture for the prototype telescope. More than fifty (50) drawings were generated for various components of the prototype telescope. Some of these parts were subsequently fabricated at UAH machine shop or at MSFC or by the outside contractors. UAH also provide technical support to MSFC staff for a number of preliminary and critical design reviews. These design reviews included PDR and CDR for the mirror assembly by United Technologies Optical Systems (UTOS), and the program quarterly reviews, and SXI PDR and CDR. UAH staff also regularly attended the monthly status reviews, and made a significant number of suggestions to improve

  6. SXI prototype mirror mount

    NASA Technical Reports Server (NTRS)

    1995-01-01

    The purpose of this contract was to provide optomechanical engineering and fabrication support to the Solar X-ray Imager (SXI) program in the areas of mirror, optical bench and camera assemblies of the telescope. The Center for Applied Optics (CAO) worked closely with the Optics and S&E technical staff of MSFC to develop and investigate the most viable and economical options for the design and fabrication of a number of parts for the various telescope assemblies. All the tasks under this delivery order have been successfully completed within budget and schedule. A number of development hardware parts have been designed and fabricated jointly by MSFC and UAH for the engineering model of SXI. The major parts include a nickel electroformed mirror and a mirror mount, plating and coating of the ceramic spacers, and gold plating of the contact rings and fingers for the camera assembly. An aluminum model of the high accuracy sun sensor (HASS) was also designed and fabricated. A number of fiber optic tapers for the camera assembly were also coated with indium tin oxide and phosphor for testing and evaluation by MSFC. A large number of the SXI optical bench parts were also redesigned and simplified for a prototype telescope. These parts include the forward and rear support flanges, front aperture plate, the graphite epoxy optical bench and a test fixture for the prototype telescope. More than fifty (50) drawings were generated for various components of the prototype telescope. Some of these parts were subsequently fabricated at UAH machine shop or at MSFC or by the outside contractors. UAH also provide technical support to MSFC staff for a number of preliminary and critical design reviews. These design reviews included PDR and CDR for the mirror assembly by United Technologies Optical Systems (UTOS), and the program quarterly reviews, and SXI PDR and CDR. UAH staff also regularly attended the monthly status reviews, and made a significant number of suggestions to improve

  7. Kinematic high bandwidth mirror mount

    DOEpatents

    Kuklo, Thomas C.

    1995-01-01

    An adjustable mirror mount system for a mirror is disclosed comprising a mirror support having a planar surface thereon, a mirror frame containing a mirror and having a planar surface behind the mirror facing the planar surface of the mirror support and parallel to the reflecting surface of the mirror and mounted pivotally to the mirror support at a point central to the frame, a first adjustment means between the mirror support and the mirror frame spaced from the central pivot mount for adjusting the movement of the mirror along one axis lying in the plane of the planar surface of the mirror frame; and a second adjustment means between the mirror support and the mirror frame spaced from the central pivot mount for adjusting the movement of the mirror along a second axis lying in the plane of the planar surface of the mirror frame and perpendicular to the first axis.

  8. Solar panel parallel mounting configuration

    NASA Technical Reports Server (NTRS)

    Mutschler, Jr., Edward Charles (Inventor)

    1998-01-01

    A spacecraft includes a plurality of solar panels interconnected with a power coupler and an electrically operated device to provide power to the device when the solar cells are insolated. The solar panels are subject to bending distortion when entering or leaving eclipse. Spacecraft attitude disturbances are reduced by mounting each of the solar panels to an elongated boom made from a material with a low coefficient of thermal expansion, so that the bending of one panel is not communicated to the next. The boom may be insulated to reduce its bending during changes in insolation. A particularly advantageous embodiment mounts each panel to the boom with a single mounting, which may be a hinge. The single mounting prevents transfer of bending moments from the panel to the boom.

  9. Kinematic high bandwidth mirror mount

    DOEpatents

    Kuklo, T.C.

    1995-03-21

    An adjustable mirror mount system for a mirror is disclosed comprising a mirror support having a planar surface thereon, a mirror frame containing a mirror and having a planar surface behind the mirror facing the planar surface of the mirror support and parallel to the reflecting surface of the mirror and mounted pivotally to the mirror support at a point central to the frame, a first adjustment means between the mirror support and the mirror frame spaced from the central pivot mount for adjusting the movement of the mirror along one axis lying in the plane of the planar surface of the mirror frame; and a second adjustment means between the mirror support and the mirror frame spaced from the central pivot mount for adjusting the movement of the mirror along a second axis lying in the plane of the planar surface of the mirror frame and perpendicular to the first axis. 7 figures.

  10. Head perturbations during walking while viewing a head-fixed target

    NASA Technical Reports Server (NTRS)

    Das, Vallabh E.; Zivotofsky, Ari Z.; Discenna, Alfred O.; Leigh, R. John

    1995-01-01

    Inexpensive, head-fixed computer displays are now available that subjects can wear during locomotion. Our hypothesis is that viewing a head-fixed visual display will change the character- istics of rotational head perturbations during natural walking. Using a 3-axis angular rate sensor, we measured head rotations during natural or treadmill walking, in 10 normal subjects and 2 patients with deficient vestibular function, as they attempted to view (1) a stationary target at optical infinity; and (2) a target at a distance of 20 cm rigidly attached to the head. Normal subjects and patients showed no significant change in the predominant frequency of head rotations in any plane (ranging 0.7-5.7 Hz) during the two different viewing tasks. Mean peak head velocities also showed no difference during the two viewing conditions except in the yaw plane, in which values were greater while viewing the near target. Predominant frequencies of head rotations were similar in the pitch plane during natural or treadmill walking; however, peak velocities of pitch head rotations were substantially greater during natural walking. One vestibular patient showed modest increases of head velocity during natural walking compared with normal subjects. Rotational head perturbations that occur during natural walking are largely unaffected when subjects view a head-fixed target. There is need to study how such perturbations, which induce vestibular eye movements, affect vision of head-fixed displays.

  11. Dry tilt network at Mount Rainier, Washington

    USGS Publications Warehouse

    Dzurisin, Daniel; Johnson, Daniel J.; Symonds, R.B.

    1984-01-01

    In addition to its primary responsibility of monitoring active Mount St. Helens, the David A. Johnston Cascades Volcano Observatory (CVO) has been charged with obtaining baseline geodetic and geochemical information at each of the other potentially active Cascade volcanoes. Dry tilt and/or trilateration networks were established during 1975-82 at Mount Baker, Mount St. Helens, Mount Hood, Mount Shasta, Lassen Peak, Crater Lake, and Long Valley caldera; coverage was extended during September 1982 to include Mount Rainier.

  12. Retired NASA F-18 being mounted on pedestal mount at Lancaster California Municipal Baseball Stadium

    NASA Technical Reports Server (NTRS)

    1997-01-01

    Workers carefully align a mounting bracket attached to an F/A-18 Hornet aircraft with the top of a pedestal in front of the municipal baseball stadium in the city of Lancaster, California. The Blue-and-white twin-jet aircraft, formerly flown as a safety chase and support aircraft by NASA's Dryden Flight Research Center, Edwards, California, was loaned to the city for display following its recent retirement. Known as 'The Hangar,' the stadium is the home field of the Lancaster Jethawks, a Class-A farm team of the Seattle Mariners.

  13. Retired NASA F-18 being mounted on pedestal mount at Lancaster California Municipal Baseball Stadium

    NASA Technical Reports Server (NTRS)

    1997-01-01

    An F/A-18 Hornet aircraft formerly flown by NASA's Dryden Flight Research Center, Edwards, California, is sandwiched between two groups of workers as they mount it atop a pedestal at the municipal baseball stadium in the city of Lancaster, California. NASA Dryden had flown the blue-and-white twin-jet as a safety chase and support aircraft for about nine years prior to its recent retirement. The aircraft is now in loan to the city for public display. Known as 'The Hangar,' the stadium is the home field of the Lancaster Jethawks, a Class-A farm team of the Seattle Mariners.

  14. Examiner's finger-mounted fetal tissue oximetry

    NASA Astrophysics Data System (ADS)

    Kanayama, Naohiro; Niwayama, Masatsugu

    2014-06-01

    The best way to assess fetal condition is to observe the oxygen status of the fetus (as well as to assess the condition of infants, children, and adults). Previously, several fetal oximeters have been developed; however, no instrument has been utilized in clinical practice because of the low-capturing rate of the fetal oxygen saturation. To overcome the problem, we developed a doctor's finger-mounted fetal tissue oximeter, whose sensor volume is one hundredth of the conventional one. Additionally, we prepared transparent gloves. The calculation algorithm of the hemoglobin concentration was derived from the light propagation analysis based on the transport theory. We measured neonatal and fetal oxygen saturation (StO2) with the new tissue oximeter. Neonatal StO was measured at any position of the head regardless of amount of hair. Neonatal StO was found to be around 77%. Fetal StO was detected in every position of the fetal head during labor regardless of the presence of labor pain. Fetal StO without labor pain was around 70% in the first stage of labor and around 60% in the second stage of labor. We concluded that our new concept of fetal tissue oximetry would be useful for detecting fetal StO in any condition of the fetus.

  15. Examiner's finger-mounted fetal tissue oximetry.

    PubMed

    Kanayama, Naohiro; Niwayama, Masatsugu

    2014-06-01

    The best way to assess fetal condition is to observe the oxygen status of the fetus (as well as to assess the condition of infants, children, and adults). Previously, several fetal oximeters have been developed; however, no instrument has been utilized in clinical practice because of the low-capturing rate of the fetal oxygen saturation. To overcome the problem, we developed a doctor's finger-mounted fetal tissue oximeter, whose sensor volume is one hundredth of the conventional one. Additionally, we prepared transparent gloves. The calculation algorithm of the hemoglobin concentration was derived from the light propagation analysis based on the transport theory. We measured neonatal and fetal oxygen saturation (StO₂) with the new tissue oximeter. Neonatal StO₂ was measured at any position of the head regardless of amount of hair. Neonatal StO₂ was found to be around 77%. Fetal StO₂ was detected in every position of the fetal head during labor regardless of the presence of labor pain. Fetal StO₂ without labor pain was around 70% in the first stage of labor and around 60% in the second stage of labor. We concluded that our new concept of fetal tissue oximetry would be useful for detecting fetal StO₂ in any condition of the fetus.

  16. The glass dome: low-occlusion obstacle symbols for conformal displays

    NASA Astrophysics Data System (ADS)

    Peinecke, Niklas; Chignola, Alvaro; Schmid, Daniela; Friedl, Hartmut

    2016-05-01

    Contemporary helmet mounted displays integrate high-resolution display units together with precise head-tracking solutions. This combination offers the opportunity to show symbols in a conformal way. Conformality here means that a hazard symbol is linked to the outside scenery. Thus, a pilot intuitively understands the connection between the symbol and its corresponding terrain feature, even if the feature is not fully visible due to degraded visual conditions. To accomplish this purpose the symbol has to be sufficiently noticeable in terms of size and brightness. However, this gives rise to the danger that parts of the outside scenery are occluded by the symbol. Furthermore, symbols should not clutter the display, in order not to distract the pilot. We present a solution framework of highlighting obstacles by symbols that balance low occlusion against noticeability. Our concept allows including different representations for individual classes of obstacles in a unified way. We detail the implementation of the display symbols. Finally, we present results of a first acceptance test with pilots.

  17. Solar panel truss mounting systems and methods

    DOEpatents

    Al-Haddad, Tristan Farris; Cavieres, Andres; Gentry, Russell; Goodman, Joseph; Nolan, Wade; Pitelka, Taylor; Rahimzadeh, Keyan; Brooks, Bradley; Lohr, Joshua; Crooks, Ryan; Porges, Jamie; Rubin, Daniel

    2015-10-20

    An exemplary embodiment of the present invention provides a solar panel truss mounting system comprising a base and a truss assembly coupled to the base. The truss assembly comprises a first panel rail mount, second panel rail mount parallel to the first panel rail mount, base rail mount parallel to the first and second panel rail mounts, and a plurality of support members. A first portion of the plurality of support members extends between the first and second panel rail mounts. A second portion of the plurality of support members extends between the first panel rail mount and the base rail mount. A third portion of the plurality of support members extends between the second panel rail mount and the base rail mount. The system can further comprise a plurality of connectors for coupling a plurality of photovoltaic solar panels to the truss assembly.

  18. Solar panel truss mounting systems and methods

    DOEpatents

    Al-Haddad, Tristan Farris; Cavieres, Andres; Gentry, Russell; Goodman, Joseph; Nolan, Wade; Pitelka, Taylor; Rahimzadeh, Keyan; Brooks, Bradley; Lohr, Joshua; Crooks, Ryan; Porges, Jamie; Rubin, Daniel

    2016-06-28

    An exemplary embodiment of the present invention provides a solar panel truss mounting system comprising a base and a truss assembly coupled to the base. The truss assembly comprises a first panel rail mount, second panel rail mount parallel to the first panel rail mount, base rail mount parallel to the first and second panel rail mounts, and a plurality of support members. A first portion of the plurality of support members extends between the first and second panel rail mounts. A second portion of the plurality of support members extends between the first panel rail mount and the base rail mount. A third portion of the plurality of support members extends between the second panel rail mount and the base rail mount. The system can further comprise a plurality of connectors for coupling a plurality of photovoltaic solar panels to the truss assembly.

  19. Optical mounts for harsh environments

    NASA Astrophysics Data System (ADS)

    Mimovich, Mark E.; Griffee, Jonathan C.; Goodding, James C.

    2009-08-01

    Development and testing of a lightweight-kinematic optical mount with integrated passive vibration-and-shock mitigation technologies and simple / robust optical alignment functionality is presented. Traditionally, optical mounts are designed for use in laboratory environments where the thermal-mechanical environments are carefully controlled to preserve beam path conditions and background disturbances are minimized to facilitate precise optically based measurements. Today's weapon and surveillance systems, however, have optical sensor suites where static and dynamic alignment performance in the presence of harsh operating environments is required to nearly the same precision and where the system cannot afford the mass of laboratory-grade stabilized mounting systems. Jitter and alignment stability is particularly challenging for larger optics operating within moving vehicles and aircraft where high shock and significant temperature excursions occur. The design intent is to have the mount be suitable for integration into existing defense and security optical systems while also targeting new commercial and military components for improved structural dynamic and thermal distortion performance. A mount suitable for moderate-sized optics and an integrated disturbance-optical metrology system are described. The mount design has performance enhancements derived from the integration of proven aerospace mechanical vibration and shock mitigation technologies (i.e. multi-axis passive isolation and integral damping), precision alignment adjustment and lock-out functionality, high dimensional stability materials and design practices which provide benign optical surface figure errors under harsh thermal-mechanical loading. Optical jitter, alignment, and wave-front performance testing of an eight-inch-aperture optical mount based on this design approach are presented to validate predicted performance improvements over an existing commercial off-the-shelf (COTS) design.

  20. Head Tilt

    MedlinePlus

    ... Throat Emotional Problems Eyes Fever From Insects or Animals Genitals and Urinary Tract Glands & Growth Head Neck & Nervous System Heart Infections Learning Disabilities Obesity Orthopedic Prevention Sexually Transmitted Skin Tobacco ...

  1. Head Noises.

    ERIC Educational Resources Information Center

    Senior, Tom

    2000-01-01

    Explains how a toy called "Sound Bites" can be modified to demonstrate the transmission of sound waves. Students can hear music from the toy when they press it against any bone in their heads or shoulders. (WRM)

  2. Head Injuries

    MedlinePlus

    ... before. Often, the injury is minor because your skull is hard and it protects your brain. But ... injuries can be more severe, such as a skull fracture, concussion, or traumatic brain injury. Head injuries ...

  3. Head lice

    MedlinePlus

    ... make the nits easier to remove. Some dishwashing detergents can help dissolve the "glue" that makes the ... clothes and bed linens in hot water with detergent. This also helps prevent head lice from spreading ...

  4. Head Injuries

    MedlinePlus

    ... won't stop crying complains of head and neck pain (younger or nonverbal children may be more fussy) ... vision pupils of unequal size weakness or paralysis neck pain or stiffness seizure If your child is unconscious: ...

  5. Diffractive optics for compact flat panel displays. Final report

    SciTech Connect

    Sweeney, D.; DeLong, K.

    1997-04-29

    Three years ago LLNL developed a practical method to dramatically reduce the chromatic aberration in single element diffractive imaging lenses. High efficiency, achromatic imaging lenses have been fabricated for human vision correction. This LDRD supported research in applying our new methods to develop a unique, diffraction-based optical interface with solid state, microelectronic imaging devices. Advances in microelectronics have led to smaller, more efficient components for optical systems. There have, however, been no equivalent advances in the imaging optics associated with these devices. The goal of this project was to replace the bulky, refractive optics in typical head-mounted displays with micro-thin diffractive optics to directly image flat-panel displays into the eye. To visualize the system think of the lenses of someone`s eyeglasses becoming flat-panel displays. To realize this embodiment, we needed to solve the problems of large chromatic aberrations and low efficiency that are associated with diffraction. We have developed a graceful tradeoff between chromatic aberrations and the diffractive optic thickness. It turns out that by doubling the thickness of a micro-thin diffractive lens we obtain nearly a two-times improvement in chromatic performance. Since the human eye will tolerate one diopter of chromatic aberration, we are able to achieve an achromatic image with a diffractive lens that is only 20 microns thick, versus 3 mm thickness for the comparable refractive lens. Molds for the diffractive lenses are diamond turned with sub-micron accuracy; the final lenses are cast from these molds using various polymers. We thus retain both the micro- thin nature of the diffractive optics and the achromatic image quality of refractive optics. During the first year of funding we successfully extended our earlier technology from 1 cm diameter optics required for vision applications up to the 5 cm diameter optics required for this application. 3 refs., 6 figs.

  6. Color Breakup In Sequentially-Scanned LC Displays

    NASA Technical Reports Server (NTRS)

    Arend, L.; Lubin, J.; Gille, J.; Larimer, J.; Statler, Irving C. (Technical Monitor)

    1994-01-01

    In sequentially-scanned liquid-crystal displays the chromatic components of color pixels are distributed in time. For such displays eye, head, display, and image-object movements can cause the individual color elements to be visible. We analyze conditions (scan designs, types of eye movement) likely to produce color breakup.

  7. 49 CFR 572.112 - Head assembly.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) ANTHROPOMORPHIC TEST DEVICES Side Impact Hybrid Dummy...) accelerometers that are mounted in conformance to § 572.36 (c). (a) Test procedure. (1) Soak the head assembly in a test environment at any temperature between 18.9 and 25.6 degrees C. (66 to 78 degrees F.) and...

  8. Ice Volumes on Cascade Volcanoes: Mount Rainier, Mount Hood, Three Sisters, and Mount Shasta

    USGS Publications Warehouse

    Driedger, Carolyn L.; Kennard, Paul M.

    1986-01-01

    During the eruptions of Mount St. Helens the occurrence of floods and mudflows made apparent the need for predictive water-hazard analysis of other Cascade volcanoes. A basic requirement for such analysis is information about the volumes and distributions of snow and ice on other volcanoes. A radar unit contained in a backpack was used to make point measurements of ice thickness on major glaciers of Mount Rainier, Wash.; Mount Hood, Oreg.; the Three Sisters, Oreg.; and Mount Shasta, Calif. The measurements were corrected for slope and were used to develop subglacial contour maps from which glacier volumes were measured. These values were used to develop estimation methods for finding volumes of unmeasured glaciers. These methods require a knowledge of glacier slope, altitude, and area and require an estimation of basal shear stress, each estimate derived by using topographic maps updated by aerial photographs. The estimation methods were found to be accurate within ?20 percent on measured glaciers and to be within ?25 percent when applied to unmeasured glaciers on the Cascade volcanoes. The estimation methods may be applicable to other temperate glaciers in similar climatic settings. Areas and volumes of snow and ice are as follows: Mount Rainier, 991 million ft2, 156 billion ft3; Mount Hood, 145 million ft2, 12 billion ft3; Three Sisters, 89 million ft2, 6 billion ft3; and Mount Shasta, 74 million ft2, 5 billion ft3. The distribution of ice and firn patches within 58 glacierized basins on volcanoes is mapped and listed by altitude and by watershed to facilitate water-hazard analysis.

  9. Evolution: Five Heads Are Better Than One.

    PubMed

    Phillips, Patrick C

    2016-04-04

    Three newly discovered species of fig-living nematodes display remarkable diversity in head morphology depending on their local environment. This shows that a great deal of ecological diversity can be maintained in the absence of substantial genetic variation.

  10. Comparison of head-steered and aircraft-fixed infrared imagery for employing the AGM-65 Maverick missile

    NASA Astrophysics Data System (ADS)

    Osgood, Robert K.; Wells, Maxwell J.; Meador, Douglas P.

    1995-05-01

    Eight veteran USAF fighter pilots, experienced with AGM-65 Maverick air-to-ground missiles, flew a night, low-level ground attack mission in a flight simulator equipped with a helmet-mounted display (HMD). The mission was performed by delivering five Maverick missiles against ground vehicles using either an aircraft-fixed forward-looking infrared (FLIR) sensor image on a head-up display (HUD) or a head-steered FLIR as the missile aiming device. Additionally, the pilots employed their weapons by two methods: fixing and launching missiles singly or in varying numbers (multiple method). The purpose of the experiment was to determine what, if any, advantage there is to employing the AGM-65 using the HMD FLIR image to slew the missile seeker onto the target versus the conventional method of using the FLIR image displayed on the HUD. With a head-steered sensor (and fixing and launching weapons singly) subjects released their weapons quicker (14.6 second interval between launches vs. 17.1 sec.), at a higher altitude (1739 feet vs. 1603 ft.), and slightly farther from the target (3.42 nautical miles vs. 3.37 nm). Furthermore, data indicated the pilots looked farther off-boresight when searching for and locking the weapon onto a target, thereby more effectively using the full field-of-regard of the missile seeker. The participants also contributed their opinions of the advantages and disadvantages of the two mechanizations.

  11. VIBRATION DAMPING AND SHOCK MOUNT

    DOEpatents

    Stevens, D.J.; Forman, G.W.

    1963-12-10

    A shock absorbing mount in which vibrations are damped by an interference fit between relatively movable parts of the mount is described. A pair of generally cup-shaped parts or members have skirt portions disposed in an oppositely facing nesting relationship with the skirt of one member frictionally engaging the skirt of the other. The outermost skirt may be slotted to provide spring-like segments which embrace the inner skirt for effecting the interference fit. Belleville washers between the members provide yieldable support for a load carried by the mount. When a resonant frequency of vibration forces acting upon the moumt attains a certain level the kinetic energy of these forces is absorbed by sliding friction between the parts. (AEC)

  12. Mounting clips for panel installation

    DOEpatents

    Cavieres, Andres; Al-Haddad, Tristan; Goodman, Joseph; Valdes, Francisco

    2017-02-14

    An exemplary mounting clip for removably attaching panels to a supporting structure comprises a base, spring locking clips, a lateral flange, a lever flange, and a spring bonding pad. The spring locking clips extend upwardly from the base. The lateral flange extends upwardly from a first side of the base. The lateral flange comprises a slot having an opening configured to receive at least a portion of one of the one or more panels. The lever flange extends outwardly from the lateral flange. The spring bonding flange extends downwardly from the lever flange. At least a portion of the first spring bonding flange comprises a serrated edge for gouging at least a portion of the one or more panels when the one or more panels are attached to the mounting clip to electrically and mechanically couple the one or more panels to the mounting clip.

  13. On and Off the Horse: Mechanisms and Patterns of Injury in Mounted and Unmounted Equestrians

    PubMed Central

    Carmichael, Samuel P.; Davenport, Daniel L.; Kearney, Paul A.; Bernard, Andrew C.

    2014-01-01

    Introduction The purpose of this study is to determine whether discrepant patterns of horse-related trauma exist in mounted versus unmounted equestrians from a single Level 1 trauma center to guide awareness of injury prevention. Methods Retrospective data were collected from the University of Kentucky Trauma Registry for patients admitted with horse-related injuries between January 2003 and December 2007 (n=284). Injuries incurred while mounted were compared with those incurred while unmounted. Results Of 284 patients, 145 (51%) subjects were male with an average age of 37.2 years (S.D. 17.2). Most injuries occurred due to falling off while riding (54%) or kick (22%), resulting in extremity fracture (33%) and head injury (27%). Mounted equestrians more commonly incurred injury to the chest and lower extremity while unmounted equestrians incurred injury to the face and abdomen. Head trauma frequency was equal between mounted and unmounted equestrians. There were 3 deaths, 2 of which were due to severe head injury from a kick. Helmet use was confirmed in only 12 cases (6%). Conclusion This evaluation of trauma in mounted versus unmounted equestrians indicates different patterns of injury, contributing to the growing body of literature in this field. We find interaction with horses to be dangerous to both mounted and unmounted equestrians. Intervention with increased safety equipment practice should include helmet usage while on and off the horse. PMID:24767580

  14. Precision alignment and mounting apparatus

    NASA Technical Reports Server (NTRS)

    Preston, Dennis R. (Inventor)

    1993-01-01

    An alignment and mounting apparatus for mounting two modules (10,12) includes a first portion having a cylindrical alignment pin (16) projecting normal to a module surface, a second portion having a three-stage alignment guide (18) including a shoehorn flange (34), a Y-slot (42) and a V-block (22) which sequentially guide the alignment pin (16) with successively finer precision and a third portion in the form of a spring-loaded captive fastener (20) for connecting the two modules after alignment is achieved.

  15. Steering a simulated unmanned aerial vehicle using a head-slaved camera and HMD

    NASA Astrophysics Data System (ADS)

    de Vries, Sjoerd C.; Padmos, Pieter

    1997-06-01

    Military use of unmanned aerial vehicles (UAVs) is gaining importance. Video cameras in these devices are often operated with joysticks and their image is displayed on a CRT. In this experiment, the simulated camera of a simulated UAV was slaved to the operator's head movements and displayed using a helmet mounted display (HMD). The task involved maneuvering a UAV along a winding course marked by tress. The influence of several parameters of the set-up on a set of flight handling characteristics was assessed. To enable variation of FOV and to study the effect of the HMD optics, a simulated HMD consisting of a head slaved window, was projected on a screen. One of the FOVs, generated in this way, corresponded with the FOV of the real HMD, enabling a comparison. The results show that the simulated HMD yields a significantly better performance that the real HMD. Performance with a FOV of 17 degrees is significantly lower than with 34 or 57 degrees. An image lag of 50 ms, typical of pan-and-tilt servo motor systems, has a small but significant influence on steering accuracy. Monocular and stereoscopic presentation did not result in significant performance differences.

  16. Simulator evaluation of takeoff performance monitoring system displays

    NASA Technical Reports Server (NTRS)

    Middleton, David B.; Person, Lee H., Jr.; Srivatsan, Raghavachari

    1988-01-01

    The development of head-up and head-down cockpit displays to convey symbolic status and advisory information to the pilot to aid him in his decision to continue or abort takeoff is described. It also describes a pilot-in-the-loop evaluation of the displays using the NASA Langley transport systems research vehicle fixed-base simulator. It was found that the head-up display was monitored with little effort and did not obstruct or distract from the runway scene.

  17. Takeoff Performance Monitoring System display options

    NASA Technical Reports Server (NTRS)

    Middleton, David B.; Srivatsan, Raghavachari; Person, Lee H., Jr.

    1992-01-01

    The development of displays for the Takeoff Performance Monitoring System (TPMS) is described with attention given to the three concepts prepared for commercial applications. The TPMS algorithm is described and related to the display requirements for pilots of two-engine airplanes. Head-up and -down displays are considered for displaying the simple advisory data which indicate whether the takeoff is a 'Go' or 'No-go' based on engine failure, acceleration error, and runway length. Six pilots are shown the three display options which include: (1) basic information; (2) basic data with 'Go/No-go' advisory flags; and (3) basic data, advisory flags, and an abort-warning symbol. The pilots tended to select the option with the most advisory data available, but the inconclusive preference study led to the concept of presenting all three configurations as possible display options for the TPMS.

  18. Portable human/computer interface mounted in eyewear

    NASA Astrophysics Data System (ADS)

    Spitzer, Mark B.; Aquilino, P. D.; Olson, Mark H.; McClelland, Robert W.; Rensing, Noa M.

    1998-08-01

    This paper presents results on the development of an eyeglass based human/computer interface. The interface comprises a display mounted within the eyeglasses, and a lens for relaying information inconspicuously to the wearer's eye. The paper will discuss eyeglass interface systems that utilize miniature displays and magnifying optics to provide a field of view of up to 10 degrees, with a resolution of approximately .03 degrees per pixel. Details of the design and construction of such systems, including methods of addressing the need for prescriptive correction will be presented. The paper concludes with comments on adding other new features to the interface system.

  19. Ergonomic design considerations for an optical data link between a warfighter's head and body-worn technologies

    NASA Astrophysics Data System (ADS)

    Trew, Noel; Linn, Aaron; Nelson, Zac; Burnett, Greg; Sedillo, Mike

    2012-06-01

    Today, warfighters are burdened by a web of cables linking technologies that span the head and torso regions of the body. These cables help to provide interoperability between helmet-worn peripherals such as head mounted displays (HMDs), cameras, and communication equipment with chest-worn computers and radios. Although promoting enhanced capabilities, this cabling also poses snag hazards and makes it difficult for the warfighter to extricate himself from his kit when necessary. A newly developed wireless personal area network (WPAN), one that uses optical transceivers, may prove to be an acceptable alternative to traditional cabling. Researchers at the Air Force Research Laboratory's 711th Human Performance Wing are exploring how best to mount the WPAN transceivers to the body in order to facilitate unimpeded data transfer while also maintaining the operator's natural range of motion. This report describes the two-step research process used to identify the performance limitations and usability of a body-worn optical wireless system. Firstly, researchers characterized the field of view for the current generation of optical WPAN transceivers. Then, this field of view was compared with anthropometric data describing the range of motion of the cervical vertebrae to see if the data link would be lost at the extremes of an operator's head movement. Finally, this report includes an additional discussion of other possible military applications for an optical WPAN.

  20. Mount Holyoke College Reshapes Reengineering.

    ERIC Educational Resources Information Center

    Carnevale, Madeline; Beretska, Sandra; Morrissey, Debra

    1999-01-01

    Reports on two reengineering projects at Mount Holyoke College (Massachusetts) that led participants to conclude that business process reengineering (BPR) in higher education involves a magnitude of cultural change that differentiates it significantly from BPR in the corporate world. The two projects involved redesigning a library department and…