Emily M. Stelzer

Multidimensional measure of display clutter and pilot performance for advanced head-up display.

INTRODUCTION This study was conducted to: develop a multidimensional measure of display clutter for advanced head-up displays (HUDs) incorporating enhanced and synthetic vision; assess the influence of HUD configuration on perceptions of display clutter, workload, and flight performance; model clutter scores in terms of visual display properties; and model flight performance in terms of subjective and objective clutter indices. METHODS In a flight simulator, 18 pilots with different levels of flight experience flew approaches divided into three segments. Three HUD configuration sets were presented under two levels of flight workload. Pilot ratings of overall display clutter, its underlying dimensions, and mental workload were recorded along with flight performance measures. Display image analysis software was used to measure visual properties of the HUDs. RESULTS The multidimensional measure of clutter showed internal consistency with overall perceived clutter. Calculated clutter scores were sensitive to HUD configurations and in agreement with a priori display classifications. There was a trend for the extremes of display clutter to cause higher workload and less stable performance due to cognitive complexity and a lack of information for high and low clutter displays, respectively. Multiple linear regression models of perceived clutter were developed based on HUD visual properties with predictive utility. Models of flight performance based on the clutter score and workload ratings were also developed, but with less predictive power. DISCUSSION Measures and models of display clutter are expected to be applicable to the evaluation of a range of display concepts.

Bottom-up and Top-down Contributors to Pilot Perceptions of Display Clutter in Advanced Flight Deck Technologies

Future concepts for the National Airspace System rely on technologies, such as synthetic and enhanced vision systems, to support flight efficiency associated with improved terrain and traffic awareness. While these technologies provide the pilot access to information not available with traditional flight instrumentation, the presentation of this additional information may serve to produce display clutter, thus inhibiting the processes and tasks they are designed to support. An experiment was conducted to assess pilot perceptions and identification of both bottom-up (data-driven) and top-down (knowledge-driven) contributing factors to display clutter. Results revealed the importance of both visual and information density (bottom-up and top-down factors, respectively) to the perception of clutter. Although added display elements provided pilots with critical flight information, pilots considered displays to be cluttered when the imposed visual density exceeded the information density required for specific flight tasks. These findings suggest that moderate levels of display clutter may be tolerable, to the extent that the information is relevant to the tasks at hand.

Measurement and Modeling of Display Clutter in Advanced Flight Deck Technologies

Clutter is a key concern in the design of complex displays, particularly in safety-critical domains such as aviation. The objective of this research was to investigate techniques for measuring subjective perceptions of clutter and to model the predicted impacts of clutter on pilot performance within the context of advanced flight deck technologies. Six commercial pilots flew simulated approaches under varied workload conditions with low-, medium-, and high-clutter head-up displays, rating the perceived clutter and subjective mental workload associated with each display configuration. Results revealed that high-clutter displays produced elevated reports of perceived clutter and workload due to information density or redundancy, whereas low-clutter displays were perceived as less cluttered but challenging to use due to lack of relevant information typically used during flight. A multidimensional measure of clutter was found to be more sensitive to display differences than an overall perceived rating of clutter, and low-level visual display properties were successful in predicting clutter perceptions and pilot performance. Finalized products of this research could support optimized display design through the identification of clutter thresholds and the implementation of clutter alerts, decluttering mechanisms, or both, and could be used to support display certification and acquisitions processes.

A Human Systems Integration Framework for Air Traffic Management System Design and Acquisition

The Federal Aviation Administration is working to modernize the systems used by air traffic controllers through the agency’s vision of the Next Generation Air Transportation System. These systems are acquired through the FAA’s Acquisition Management System (AMS) process. To date, human factors analysis is included in this process, though improvements can be made in the alignment of human systems integration principles with these systems engineering processes. This paper provides a recommended human systems integration framework to support air traffic management system design, and examines two potential cases in which the framework can be used to support the process.

Controller Use of a Block Occupancy-Based Surface Surveillance Display for Surface Management

Advanced surface surveillance capabilities cannot be economically justified at small and medium airports, though these airports continue to suffer from runway incursions. A block occupancy-based surface surveillance approach, in which runways and taxiways are divided into blocks and the occupancy of a block is displayed to the controller, may provide a low cost solution to these airports. A medium fidelity simulation was conducted to examine controller situation awareness, workload, and aircraft identification performance with the use of the block occupancy display. Results indicate that the presence of the display improves controller detection of safety critical runway events. However, controllers indicate that associating occupied blocks with aircraft identification is burdensome.

Data and Knowledge as Predictors of Perceptions of Display Clutter, Subjective Workload and Pilot Performance

Display clutter is defined as an unintended effect of displaying visual imagery that may obscure or confuse other information, or that may be redundant or not relevant to the task at hand. There exists a limited amount of research that has explored both data-driven and knowledge-driven parameters as dual contributors to perceptions of clutter. In the present study, six pilots flew simulated approaches under varied workload conditions with synthetic and enhanced vision display configurations that represented “low,” “medium,” and “high” clutter. Results evinced that high clutter displays produced elevated reports of perceived clutter and workload due to density or redundant presentation of information, while low clutter displays were perceived as less cluttered but challenging to use because of a lack of information typically required for flight. Pilots identified both data-driven (bottom-up) and knowledge-driven (top-down) as contributors to clutter, and these challenges were mirrored in flight technical performance. Conclusions support the notion that design of advanced technologies must consider not only the physical appearance of data within the display, but also the utility of that information to tasks the displays are designed to support.

Low cost surface awareness technology and field demonstration

Advanced surface surveillance capabilities have been shown to dramatically improve surface safety and aid in situation awareness, but these capabilities cannot be economically justified for small and medium airports. The MITRE Corporation has developed a concept for Low Cost Surface Awareness, built upon the use of commercial-off-the-shelf infrared cameras, computer vision processing, and georeferencing algorithms. The end-to-end solution was prototyped and demonstrated at Teterboro Airport. The demonstration revealed that aircraft and airport operations vehicles can be located on the airport surface with less than 35 feet error.

Supporting The Development Of Empirically Driven Human Systems Integration Guidelines For System Requirements

The Federal Aviation Administration’s vision for the Next Generation Air Transportation System (NextGen) includes the implementation of advanced automation capabilities to deliver operational benefits. As these new systems have been deployed, some inefficiencies in the systems engineering process have been noted and attributed to the failure to adequately consider human systems integration in the engineering process (GAO, 2010). Human systems integration can be improved through the definition of quantitative requirements, which ensure that systems are designed effectively and validated fully prior to implementation. This paper provides an overview of a process used to define quantitative guidelines for human systems integration and the application of that process to a set of guidelines for supporting the perception of visual and auditory displays.

Block occupancy based surface surveillance

The proposed surface surveillance concept divides airport runways and taxiways into a number of operationally suitable, discrete, and contiguous sections called blocks. The system uses magnetometers or other suitable sensors positioned at each of the block boundaries to monitor aircraft and vehicle movements into and out of these blocks. The system then indicates the block occupancy information for tower controllers on a two-dimensional (2-D) display of an airport map. This surveillance information is envisioned to improve controller situational awareness of surface operations, particularly in reduced visibility.