Head Worn Display System for Equivalent Visual Operations

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

Using Helmet Mounted Displays to Designate and Locate Targets in the Urban Environment

Technologies have developed within the last ten years to allow the Helmet Mounted Display (HMD) to be much more effective as an air-to-ground (A/G) weapons cue. HMD A/G accuracy and performance requirements should be added to the Joint Helmet Mounted Cueing System (JHMCS) specifications, detailed to be as good or better than the FA-18 heads-up-display (HUD). Because of target ranging and line-of-sight (LOS) errors, the JHMCS is only used as an area sensor cue in the urban close air support (CAS) role. Therefore, for use against point targets, improvements to JHMCS are needed. LOS errors have to be reduced from the current 13-mil error, which would equate to +/- 260 feet from a 20,000 ft slant range. To decrease this error, more accurate helmet trackers must be used with faster update rates. HMD Earth referenced symbol update rates, which are currently restricted to 20 Hz, must be increased to allow the helmet to provide accurate information, despite aggressive maneuvering or operations in a turbulent environment. Accurate ranging sources must be developed to enhance the target elevation algorithm in the FA-18 to ensure usable target data, once designations are made. During turbulent flight conditions, the difference between the actual target position on the ground and the unstable target designation (TD) diamond depicting it cause motion differences, which distract the pilot. Methods to filter the movement of earth-referenced symbols should be explored, as well as increasing JHMCS symbol write rates. Additionally, vibration levels during low-level flight and moderate turbulence levels make HMD A/G aiming and designation tasks very difficult. Buffet suppression algorithms are used during vibrations in the air-to-air (A/A) aiming role and should be implemented for A/G use as well. The purpose of this study is to focus on present capabilities with JHMCS. The author’s tactical experience has been achieved on the FA-18 A-F variants and tactical applicability will be directed to that platform. While most references to helmet displays will center on lessons learned from the JHMCS, helmet mounted display experience was gained while serving as an exchange officer with the UK Royal Air Force and evaluating the Guardian HMD system. The analysis contained within this thesis is based on the operational insights of operating within the demanding Close Air Support (CAS) environment and the tactical enhancement that has been demonstrated with the use of Helmet Mounted Cueing systems. Currently, JHMCS is available to about half the FA-18 fleet and operational assessments, resulting from its use in the Iraqi conflict, has accelerated the demand for increased capabilities to this target cueing device. Lessons learned from the current generation of HMDs will play a major role in the design of the cockpit for the Joint Strike Fighter (JSF)

Characteristics of flight simulator visual systems

The physical parameters of the flight simulator visual system that characterize the system and determine its fidelity are identified and defined. The characteristics of visual simulation systems are discussed in terms of the basic categories of spatial, energy, and temporal properties corresponding to the three fundamental quantities of length, mass, and time. Each of these parameters are further addressed in relation to its effect, its appropriate units or descriptors, methods of measurement, and its use or importance to image quality

Ability of head-mounted display technology to improve mobility in people with low vision: a systematic review

Purpose: The purpose of this study was to undertake a systematic literature review on how vision enhancements, implemented using head-mounted displays (HMDs), can improve mobility, orientation, and associated aspects of visual function in people with low vision. Methods: The databases Medline, Chinl, Scopus, and Web of Science were searched for potentially relevant studies. Publications from all years until November 2018 were identified based on predefined inclusion and exclusion criteria. The data were tabulated and synthesized to produce a systematic review. Results: The search identified 28 relevant papers describing the performance of vision enhancement techniques on mobility and associated visual tasks. Simplifying visual scenes improved obstacle detection and object recognition but decreased walking speed. Minification techniques increased the size of the visual field by 3 to 5 times and improved visual search performance. However, the impact of minification on mobility has not been studied extensively. Clinical trials with commercially available devices recorded poor results relative to conventional aids. Conclusions: The effects of current vision enhancements using HMDs are mixed. They appear to reduce mobility efficiency but improved obstacle detection and object recognition. The review highlights the lack of controlled studies with robust study designs. To support the evidence base, well-designed trials with larger sample sizes that represent different types of impairments and real-life scenarios are required. Future work should focus on identifying the needs of people with different types of vision impairment and providing targeted enhancements. Translational Relevance: This literature review examines the evidence regarding the ability of HMD technology to improve mobility in people with sight loss

Aerospace medicine and biology: A continuing bibliography with indexes (supplement 408)

This bibliography lists 84 reports, articles and other documents introduced into the NASA Scientific and Technical Information System during Dec. 1995. Subject coverage includes: aerospace medicine and physiology, life support systems and man/system technology, protective clothing, exobiology and extraterrestrial life, planetary biology, and flight crew behavior and performance

Aerospace medicine and biology: A continuing bibliography with indexes (supplement 356)

This bibliography lists 192 reports, articles and other documents introduced into the NASA Scientific and Technical Information System during November 1991. Subject coverage includes: aerospace medicine and psychology, life support systems and controlled environments, safety equipment, exobiology and extraterrestrial life, and flight crew behavior and performance

Aerospace Medicine and Biology: A continuing bibliography with indexes, supplement 182, July 1978

This bibliography lists 165 reports, articles, and other documents introduced into the NASA scientific and technical information system in June 1978

Aerospace Medicine and Biology: A continuing bibliography with indexes, supplement 217, March 1981

Approximately 130 reports, articles, and other documents introduced into the NASA scientific and technical information system in February 1981 are included in this bibliography. Topics include aerospace medicine and biology

Area of Interest Display in Visual Simulation

Visual simulation to provide effective training for airplane flight in a wide field of view, high detail environment presents problems of cost and adequate detail. Research and development to meet these problems is addressing various techniques for concentrating high image detail in an area of interest (AOI) which is set within a larger field of view of comparatively low resolution and detail. This paper reviews the various AOI techniques and suggests possible future benefits to visual simulation for the space program