Predicting the readability of transparent text

Will a simple global masking model based on image detection be successful at predicting the readability of transparent text? Text readability was measured for two types of transparent text: additive (as occurs in head-up displays) and multiplicative (which occurs in see-through liquid crystal display virtual reality displays). Text contrast and background texture were manipulated. Data from two previous experiments were also included (one using very low contrasts on plain backgrounds, and the other using higher-contrast opaque text on both plain and textured backgrounds). All variables influenced readability in at least an interactive manner. When there were background textures, the global masking index (that combines text contrast and background root mean square contrast) was a good predictor of search times (r = 0.89). When the masking was adjusted to include the text pixels as well as the background pixels in computations of mean luminance and contrast variability, predictability improved further (r = 0.91)

Preliminary study of head-up assessment techniques. 1: Viewing duration of instrument panel and HUD symbology using a recall methodology

Eight commercial pilots were shown 50 colored, high fidelity slides of a standard instrument panel (IP) with the needle positions of each instrument varying from slide to slide and then 50 slides of a head-up display (HUD) symbology format which contained an equivalent amount of flight-related information as the instrument panel slides. All stimuli were presented under controlled, static viewing conditions that allowed the measurement of the speed and accuracy with which one randomly selected flight parameter on each slide could be read. The subject did not know which parameter would be requested and, therefore, had to remember the total set of information in order to answer the question correctly. The results showed that from 6.6 - 8.7 sec total viewing time was required to correctly extract altitude, airspeed, heading, VSI, or ADI from the IP slides and from 6.1 to 7.4 sec for the HUD slides

Aspects of Synthetic Vision Display Systems and the Best Practices of the NASA's SVS Project

NASA s Synthetic Vision Systems (SVS) Project conducted research aimed at eliminating visibility-induced errors and low visibility conditions as causal factors in civil aircraft accidents while enabling the operational benefits of clear day flight operations regardless of actual outside visibility. SVS takes advantage of many enabling technologies to achieve this capability including, for example, the Global Positioning System (GPS), data links, radar, imaging sensors, geospatial databases, advanced display media and three dimensional video graphics processors. Integration of these technologies to achieve the SVS concept provides pilots with high-integrity information that improves situational awareness with respect to terrain, obstacles, traffic, and flight path. This paper attempts to emphasize the system aspects of SVS - true systems, rather than just terrain on a flight display - and to document from an historical viewpoint many of the best practices that evolved during the SVS Project from the perspective of some of the NASA researchers most heavily involved in its execution. The Integrated SVS Concepts are envisagements of what production-grade Synthetic Vision systems might, or perhaps should, be in order to provide the desired functional capabilities that eliminate low visibility as a causal factor to accidents and enable clear-day operational benefits regardless of visibility conditions

Helicopter flights with night-vision goggles: Human factors aspects

Night-vision goggles (NVGs) and, in particular, the advanced, helmet-mounted Aviators Night-Vision-Imaging System (ANVIS) allows helicopter pilots to perform low-level flight at night. It consists of light intensifier tubes which amplify low-intensity ambient illumination (star and moon light) and an optical system which together produce a bright image of the scene. However, these NVGs do not turn night into day, and, while they may often provide significant advantages over unaided night flight, they may also result in visual fatigue, high workload, and safety hazards. These problems reflect both system limitations and human-factors issues. A brief description of the technical characteristics of NVGs and of human night-vision capabilities is followed by a description and analysis of specific perceptual problems which occur with the use of NVGs in flight. Some of the issues addressed include: limitations imposed by a restricted field of view; problems related to binocular rivalry; the consequences of inappropriate focusing of the eye; the effects of ambient illumination levels and of various types of terrain on image quality; difficulties in distance and slope estimation; effects of dazzling; and visual fatigue and superimposed symbology. These issues are described and analyzed in terms of their possible consequences on helicopter pilot performance. The additional influence of individual differences among pilots is emphasized. Thermal imaging systems (forward looking infrared (FLIR)) are described briefly and compared to light intensifier systems (NVGs). Many of the phenomena which are described are not readily understood. More research is required to better understand the human-factors problems created by the use of NVGs and other night-vision aids, to enhance system design, and to improve training methods and simulation techniques

Head-up displays - A study of their applicability in civil aviation

Benefits and problems of using head-up displays in commercial and general aviation aircraf

Human Factors Criteria for Displays: A Human Factors Design Standard Update of Chapter 5

This document contains updates and expands the design criteria and information on displays from the Human Factors Design Standard. A research team of human factors experts evaluated the existing guidelines for relevancy, clarity, and usability. They drafted new guidelines as necessary based on relevant sources, and they reorganized the document to increase usability. This resulted in extensive changes to the original document including the addition of new guidelines, sources, and topic areas

Literature concerning control and display technology applicable to the Orbital Maneuvering Vehicle (OMV)

A review is presented of the literature concerning control and display technology that is applicable to the Orbital Maneuvering Vehicle (OMV), a system being developed by NASA that will enable the user to remotely pilot it during a mission in space. In addition to the general review, special consideration is given to virtual image displays and their potential for use in the system, and a preliminary partial task analysis of the user's functions is also presented

US Army Weapon Systems Human-Computer Interface (WSHCI) style guide, Version 1

A stated goal of the U.S. Army has been the standardization of the human computer interfaces (HCIS) of its system. Some of the tools being used to accomplish this standardization are HCI design guidelines and style guides. Currently, the Army is employing a number of style guides. While these style guides provide good guidance for the command, control, communications, computers, and intelligence (C4I) domain, they do not necessarily represent the more unique requirements of the Army`s real time and near-real time (RT/NRT) weapon systems. The Office of the Director of Information for Command, Control, Communications, and Computers (DISC4), in conjunction with the Weapon Systems Technical Architecture Working Group (WSTAWG), recognized this need as part of their activities to revise the Army Technical Architecture (ATA). To address this need, DISC4 tasked the Pacific Northwest National Laboratory (PNNL) to develop an Army weapon systems unique HCI style guide. This document, the U.S. Army Weapon Systems Human-Computer Interface (WSHCI) Style Guide, represents the first version of that style guide. The purpose of this document is to provide HCI design guidance for RT/NRT Army systems across the weapon systems domains of ground, aviation, missile, and soldier systems. Each domain should customize and extend this guidance by developing their domain-specific style guides, which will be used to guide the development of future systems within their domains

Helmet-Mounted Display Symbology and Stabilization Concepts

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

Human Factors Evaluation of Portable Electronic Devices in Tactical Aircraft

As the service life of aging military aircraft are extended and these aircraft are tasked with new missions they were never designed to support, military aircraft are constantly being upgraded with new systems and avionics. Additionally, many legacy aircraft have poor cockpit layouts or incorporate older displays that are not compatible with or require extensive modification to support these new technologies. Unfortunately, many acquisition programs do not have the luxury of an unlimited budget and schedule to complete the required upgrades. One alternative is to incorporate a portable electronic device or PED into the cockpit. These devices can provide moving maps, real time intelligence information, or simply transition to a paperless cockpit. Adding a PED can be a cheaper and easier alternative than redesigning the entire cockpit. Although PEDs have some cost and schedule benefits, the human factors concerns can often overshadow the money and time saved using these devices. This paper investigates the human factors and aircrew systems design considerations when integrating laptop, pentablet, and personal digital assistant (PDA) type devices into attack and strike-fighter fixed wing aircraft. The range of issues that human factors engineers must consider with any potential PED is wide-ranging, from display readability to operator training and from user interface to degraded system operation. This paper focuses on the hardware integration requirements for PEDs in tactical fixed wing aircraft. While software functionality and aircrew workload are important factors that must be considered for any system, these issues are outside the scope of this paper. When integrating a PED system, there are six critical operational issues (COI) every system must meet before it can be considered operationally effective and suitable for the cockpit environment. The six PED COIs are: The display must be easily readable under all anticipated lighting conditions ranging from direct sunlight to night time operations. Also, the display must have adequate off axis readability if the display is not in the pilot’s primary field of view or if shared by two crew members. The display lighting must be compatible with existing cockpit lighting, including night vision imaging systems (NVIS). Lighting compatibility affects both internal and external cockpit vision and the ability to shift focus from outside to inside the cockpit and vice versa. The input devices and controls must allow for fast, accurate data entry and system optimization to present mission critical information in the desired format at the appropriate time. The PED must be integrated into the cockpit so it is easily accessible to the pilot while not restricting the pilot’s access to other cockpit controls and displays. If the PED is used as an electronic kneeboard, it must be properly secured so the device remains firmly in place and is comfortable to wear, especially during dynamic maneuvering and extended combat missions. The PED must not interfere with normal and emergency ingress and egress, including the ejection process. Also, the PED should not increase the risk of injury during an emergency egress scenario. For each COI, military and Federal Aviation Administration (FAA) human factors, cockpit guidelines, and specifications are outlined and applied to PED use in a military cockpit. This paper examines several fielded systems used in both commercial and military aviation, as well as potential Commercial Off the Shelf (COTS) systems. Ground and flight test reports for fielded and developmental PEDs provide examples as to how these guidelines and specifications apply to PED integration into the cockpit. Finally, the author, a Navy test pilot with experience employing PEDs in tactical cockpits, provides an aviator perspective to these guidelines and specifications in a combat environment. Based on the PED COIs, military specifications presented, and lessons learned from currently deployed PED systems, five conclusions were made when conducting this evaluation: Pentablet computers are preferred over laptops and PDAs. PEDs should not serve as the primary indicator of safety of flight or mission critical information. Integrating COTS systems does not guarantee cost and schedule savings. Touch screens and reprogrammable push buttons are the optimum control option. PEDs should be mounted on kneeboards vice the instrument panel. PEDs have excellent potential to fulfill many roles in the tactical cockpit, including electronic checklists, navigation charts, and real time weapon system control. While PEDs may not be the perfect solution to many system integration problems, they are viable options that deserve further consideration by any program manager or acquisition professional