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This paper reports on two studies focusing on the design of collision avoidance headway displays. The first study aims at examining interface issues relating to the headway information to drivers. It investigates integrated visual and auditory warnings. The purpose of the second study is to examine two particular factors that may affect drivers' braking responses in their use of an experimental Collision Avoidance System. It looks at the effects of both the absolute speeds of the target and following vehicle and the relative speed differences between the two vehicles.

Integrated multimodal systems is one promising direction to improve human–vehicle interaction. In order to create intelligent human–vehicle interfaces and reduce visual load during secondary tasks, combining a haptic rotary device and a graphic display will provide one practical solution. However, in literature, the proper display position for the haptic rotary device is not fully investigated. In this paper, one experimental infotainment system is studied (including a haptic rotary control device and a graphic display) to evaluate the proper display position. Measurements used include task completion time, reaction to road events, lane/velocity keeping during secondary tasks, and user preference. Three display positions are considered: high mounted position, cluster position, and center stack position. The results show that, with increased on-road and off-road visual loads, the cluster display position can reduce lane position deviation significantly compared to high mounted and center stack positions. In addition, the high mounted and cluster display positions are better toward two different road events, including strong wind gust and extreme deceleration of the lead car.

The effectiveness of signal coordination can be undermined by over-long spacing and different vehicle dynamic characteristics between neighbouring signal intersections in a signalised highway system. This study presents two dynamic speed guidance (DSG) strategies based on the traffic environment and facility deployment to congregate the traffic flow and optimise the arterial coordinated signal control system. One of them is the in-car display for individual guidance, and the other is the roadside display for group guidance. The two DSG strategies are calculated using the rolling horizon approach. A simulation platform that integrates data communication, traffic mobility and DSG application is programmed based on VISSIM, a microscopic simulation model. A section of Cao'an highway is used to assess the efficiency of two DSG strategies. The assessment results show that both the average stops and travel time of arterial vehicles can be optimised with the application of the two DSG strategies. In addition, the in-car strategy provides a significant benefit for on-board unit equipped vehicles, even in a low level of market penetration rate.

An evaluation approach for correspondence-driven domains is suggested and implemented. Touch screen and trackball controls were evaluated as interaction devices for large-area displays in the cockpits of highly agile jet aircraft. To account for the context conditions of selected use cases, informatory quality and the difficulty of situational demands were analysed and manipulated experimentally in dual-task scenarios, which were completed by experienced pilots. Results indicate a clear performance advantage of touch compared to trackball interaction, accompanied by less workload. Informatory dimensions induce different performance and workload ratings. Cognitive demands interfere the least with aiming performance, followed by visual and motor. Task and device influences are interdependent. Motor components of an additional task interfere especially with trackball control actions. Workload operates as a buffer. When difficulty increases, performance decrements are lower than workload increments. It is argued that this cognitive manipulation of informatory context is advisable for correspondence-driven domains, where context is expected to influence human---machine interaction. Transfer to automotive display evaluation appears to be straightforward.

Korea is currently experiencing a rapidly increasing distribution rate of in-vehicle display devices, such as navigation or DMB displays, owing to remarkable advances in IT. At the same time, the number of traffic accidents and traffic violations is increasing due to the distraction of drivers’ attention by such devices. In particular, in-vehicle display devices such as navigation systems temporarily distract drivers’ visual or cognitive attention when they perform a unit task. Accordingly, it is necessary to prepare adequate standards to regulate in-vehicle display devices, especially in Korea. There are few empirical studies that have employed experiments to support such regulation. In this study, an experiment was conducted using a driving simulator to establish the proper standards regarding the maximum distraction time per unit task that can be allowed without causing any disturbance in safe driving. A total of 25 participants participated in the experiment. The distraction time was controlled by asking participants to perform the two tasks at once: while participants were driving as a primary task, they performed secondary task that count the number of intersections between the start point and the arrival point displayed on the screen. The results showed that the 2.0 second condition differed from the controlled condition in the deviation in the distance from the preceding vehicle, speed, and steering wheel movement, whereas there were no differences between the controlled condition and the 1.0 or 1.5 second condition. Finally, the limitations of the study and the implications of the findings with regard to future studies and application of the Korean version of guidelines for in-vehicle display devices are discussed.

This study evaluated the effect of visual pedestrian signal displays on the ability of persons with reduced visual acuity to accurately and confidently identify the pedestrian interval. While watching video clips of actual intersections presented on a 42-in. monitor under simulated visual impairment, participants attempted to determine the pedestrian interval (“Walk,” flashing “Don't Walk,” or steady “Don't Walk”) and provided confidence ratings for each judgment. Participants in Experiment 1 experienced simulated acuities of 20/70, 20/100, and 20/200; participants in Experiment 2 experienced approximate acuities of 20/20, 20/50, and 20/300. The study made a critical comparison of two methods of signaling the pedestrian change interval (i.e., flashing “Don't Walk”): (a) simultaneous presentation of a countdown and a flashing upraised hand symbol and (b) a countdown-only display without the flashing upraised hand. With the exception of performance in the 20/300 vision category, participants' accuracy on the interval discrimination task was, overall, rather high. However, under simulated visual impairment of 20/70 or worse, participants' success in correctly determining the pedestrian interval was, on average, 21.5 percentage points lower for the countdown display presented without the flashing upraised hand than for the countdown display with the upraised hand. The participants' average reported confidence in their judgment was also lower for the countdown-only condition, and their interval judgment response times also showed a negative effect of the countdown-only display. Implications of the study findings with regard to visual impairment and signal displays for the pedestrian change interval are discussed.

A real-time energy management display is developed and evaluated, and the feasibility and utility of the display in providing real-time guidance and information on an aircraft's energy state is investigated. Flight simulations were conducted with the UTSI's Aviation Systems research flight simulator to validate the display and to evaluate its utility for flying along constant specific excess power (PS) contours and for directly obtaining PS contours from level acceleration flight test. This study considers the energy state of the aircraft from the point of view of the relation that exists between specific excess power, PS, and the forces in flight. The approach yields as one result a cubic function for the PS of the aircraft. We then directly solve for velocity, V, as the control parameter for a given PS as a function of altitude, H. Using LabView software, this technique is used to build a real-time energy management display which provides guidance and real-time information on the aircraft's energy state. Flight simulation results proved the display to be successful in obtaining direct PS contours from level acceleration flight tests and in providing guidance for flights along constant PS contours at low airspeeds, although it was difficult to keep the PS constant. Santrauka Sukurtas ir įvertintas realaus laiko energijos valdymo monitorius, ištirtos jo galimybės ir panaudojimas informacijai apie energijos būklę teikti. Skrydžio simuliacijos rodo, kad monitorius sėkmingai gauna tiesioginįPSkontūrą greitėjančio skrydžio metu ir gali nukreipti skrydžius palei nuolatinįPSkontūrą, esant nedideliam greičiui, nors ir sunku išlaikyti nuolatinįPS. Reikšminiai žodžiai: perteklinė galia,horizontalusis pagreitėjimas,aukštis,greitis

Purpose: Within the context of thru-stop intersections, investigate the feasibility and future promise of warning systems inside the vehicle, where interfaces are best placed, and what modalities are most effective (visual versus haptic). Methods: A driving simulator study was conducted to compare three decision support systems (DSSs): a dynamic traffic sign, a set of displays on the vehicle side mirrors, and a vibrating seat. Dependent variables included measurements of safe driving behavior, and a usability questionnaire. A follow-up focus group study was conducted to gain further feedback on the in-vehicle systems and on ideas for how to improve the systems. Results: The vibrating seat yielded significantly higher results than the dynamic traffic sign on two safety variables. No system clearly outperformed the others in terms of promoting safer driving behavior, nor did any improve driving performance compared to the control condition. The questionnaire and usability data showed that the dynamic traffic sign was most preferred, while the in-vehicle displays were most comprehended. Comments during the simulator studies suggested that participants wanted stronger advisory messages from the systems, and the Focus Group Study confirms this. Conclusions: In-vehicle DSSs appear to be feasible for the purposes of assisting drivers with navigating rural thru-stop intersections. No results of this study indicate that in-vehicle systems are an inherently poor means of presenting traffic gap information to the driver. Results indicate that a visual display would be easier to comprehend than a vibrotactile display when no training or explanation is provided.

Occlusion is a practical technique to measure the visual demand imposed by in-vehicle tasks and to assess whether a task can be resumed having been interrupted. This study describes a number of important factors and variables that need to be controlled to ensure reliability of results. Training of participants on in-vehicle tasks is found to help consistency and five training sessions are required for complex tasks. No significant differences in training with and without occlusion goggles are reported. The required sample size is dependent on the variability of the task; for those investigated an appropriate sample size is found to be 14. For in-vehicle systems that exhibit a delay in response to the user, consistency is improved when these delays are excluded from timing measurements. In terms of calculating the occlusion parameter R, the within-participant basis is most consistent by taking the ratio of the respective median total shutter open time and total task times across trial repetitions completed by one participant on each task under evaluation and, for the purposes of identifying interface designs that exhibit poor resumability, the 85th percentile value is identified as most suitable. Findings from the study are discussed in terms of future application of the occlusion technique to assess in-vehicle information systems (IVIS).

The objectives of this study were to assess the effects of differing formats of forward-looking primary flight display (PFD; electronic attitude-direction indicator, full-color terrain, uniformly brown terrain) on general aviation (GA) pilot recoveries from unknown attitudes and to determine if recovery assistance embodied in the display could be useful. Total recovery times and control reversals were examined as indexes of performance for 40 GA pilots, and the recovery times were subjected to a comparative analysis using both a parametric difference analysis and an equivalence testing technique. Results suggest that for the specific conditions investigated, terrain-depicting PFDs supported performance that was equivalent to that observed with the standard attitude indicator. Equivalence testing is recommended for cases where it is desirable to determine if one device or system provides for performance that is equivalent to another.

INTRODUCTION: Pilots are susceptible to over-reliance on distance when making relative time-to-contact (TTC) judgments of surrounding intruders, referred to as "the distance bias." We tested the effect of adding perceptual cues and an information feature to cockpit displays of traffic information to mitigate this bias. METHOD: There were 14 general aviation pilots who participated in a simulated flight scenario and were asked to make relative TTC judgments. Three levels of perceptual cue (blinking, color-change, and no-cue) were crossed with two levels of velocity data tag (present and absent) with identification of the highest risk intruder as a response. RESULTS: Perceptual cues were associated with more accurate high-risk intruder selection (color = 95.95% correct, blinking = 95.98%, no-cue = 87.89%), decreased response time (color = 3.68 s, blinking = 3.19 s, no-cue = 6.08 s), reduced visual attention demand (color = 57% of attention, blinking = 58%, no-cue = 62%), lower workload ratings (color = 28.38/100, blinking = 29.66/100, no-cue = 48.91/100), and higher performance confidence ratings (color = 83.92/100, blinking = 82.71/100, no-cue = 58.85/100) than the no-cue displays. There was no difference between blinking and color cue displays. The data tag was associated with lower response times (present = 4.13 s, absent = 4.50 s) and higher confidence ratings (present = 78.69/100, absent = 71.63/100) than displays without. Displays including the blinking cue, color-change cue, and data tag were preferred over displays that did not include these features (color = 8 pilots, blinking = 6, no-cue = 0). DISCUSSION: The added display features were effective in mitigating the effect of the distance bias on pilot performance measures and received favorable subjective ratings. Language: en

Objective: An evaluation study was conducted to answer the question of which system properties of night vision enhancement systems (NVESs) provide a benefit for drivers without increasing their workload. Background: Different infrared sensor, image processing, and display technologies can be integrated into an NVES to support nighttime driving. Because each of these components has its specific strengths and weaknesses, careful testing is required to determine their best combination. Method: Six prototypical systems were assessed in two steps. First, a heuristic evaluation with experts from ergonomics, perception, and traffic psychology was conducted. It produced a broad overview of possible effects of system properties on driving. Based on these results, an experimental field study with 15 experienced drivers was performed. Criteria used to evaluate the development potential of the six prototypes were the usability dimensions of effectiveness, efficiency, and user satisfaction (International Organization for Standardization, 1998). Results: Results showed that the intelligibility of information, the easiness with which obstacles could be located in the environment, and the position of the display presenting the output of the system were of crucial importance for the usability of the NVES and its acceptance. Conclusion: All relevant requirements are met best by NVESs that are positioned at an unobtrusive location and are equipped with functions for the automatic identification of objects and for event-based warnings. Application: These design recommendations and the presented approach to evaluate the systems can be directly incorporated into the development process of future NVESs.

Cockpit displays of traffic information are designed to support pilots' abilities to perform conflict detection and resolution tasks. Three experiments investigated the effects of display dimensionality, conflict geometry, and time pressure of in-flight conflicts on performance. The results indicated that interactive viewpoints in 2 3-D displays eliminated ambiguity costs, resulting in performance on both tasks comparable to a 2-D coplanar display. Viewpoint interactivity in the 3-D displays was vulnerable to increased workload, although corresponding performance was no worse than the 2-D coplanar. All 3 display formats showed performance decrements for nonlevel conflict geometries and increased time pressure. Language: en

An operational evaluation of the automatic dependent surveillance system and cockpit display of traffic information (CDTI) provided an opportunity to examine how pilot use of CDTI enabled them to maintain predefined spacing intervals from other aircraft. Seventy percent of the controller -issued traffic calls resulted in positive visual acquisitions (83% displayed on CDTI). Approximately 55% of the approach clearances that included instructions to "follow that traffic" involved communication problems and operational concerns. In light of the findings and the participants' comments, changes to proposed procedures and supporting phraseology will be constructed and evaluated for the approach spacing application.

One of the most difficult aspects of manually controlled flight is the coupling between the control over the aircraft speed and altitude. These states cannot be changed independent of each other through the aircraft control devices, the elevator and the throttle. Rather, to effectively change an aircraft's speed and altitude, the controls have to be coordinated. The mediating mechanism that underlies the coordination of the controls is the management of the aircraft's energy state. This article shows that the abstraction hierarchy (AH; Rasmussen, 1986) framework can be effectively used to gain more insight into the underlying structure of the aircraft energy management problem. The derived AH representation is based on the analysis of the energy constraints on the control task. It reveals the levels of abstraction necessary to link the aircraft's physical controls to the speed and altitude goals and also how the aircraft energy is a critical mediating state of the control problem. Energy awareness can be ...

In 3 experiments, we examined maneuver choice, flight safety, and mental workload across 3-dimensional (3D) perspective and 2-dimensional coplanar cockpit displays of traffic information in a free-flight simulation. In Experiment 1 (30 pilots), we examined dimensionality issues; in Experiments 2 and 3 (18 pilots each), we examined the effects of traffic density, dimensionality, and vertical profile orientation. Collectively, these data may be modeled by trade-offs between the display types: The coplanar suite suffers from scanning-related integration that increases with conflict density; the 3D display suffers from perceptual ambiguity. This research informs our understanding of how displays modulate performance in free-flight environments.

Licensed mariners carried out two simulated navigation studies testing electronic chart and information display systems (ECDIS) against paper chart navigation. In the first study, six mariners each completed approaches to Halifax, Nova Scotia, harbour with good and bad visibility and a range of wind and currents. Conditions included chart with radar, ECDIS with radar overlay and ECDIS with separate radar. ECDIS produced better performance and a smaller workload than paper charts and the radar overlay was slightly better than the separate radar display. In the second study, six new mariners completed exercises with low visibility and heavy or light radar traffic using ECDIS with radar overlay, ECDIS without overlay and ECDIS with optional overlay. Mariners preferred the optional overlay but all three conditions produced about equal performance. Based on mariners' performance and expressed preference, we recommend that ECDIS systems provide optional radar overlays.

Synthetic vision information systems (SVIS) are the next generation of cockpit display systems that will become an integral part of the commercial flight deck in the future. The goal of this study was to evaluate SVIS against conventional glass cockpit displays to assess whether or not SVIS can improve pilot performance, situation awareness (SA), and workload. The evaluation was conducted in a fixed-base laboratory flight simulator located in the Operator Performance Laboratory at the University of Iowa. A total of 12 pilot evaluators hand-flew fairly difficult approaches into the Eagle County, Colorado, airport. Specially designed questionnaires were used in various phases of the flights to estimate workload, SA, and user preference. Information relating to SA was collected using the Situation Awareness Global Assessment Technique and workload estimates were obtained using the NASA Task Loading Index technique. Eye movement data were collected using a modified IScan ETL 500 system, and analyzed to find a...

The retrofit question concerns whether useful and effective synthetic vision displays are usable in aircraft that have limited-size display spaces. Two experiments were conducted to examine the efficacy of these displays and develop field-of-view and terrain texture recommendations for design. The first experiment examined issues of field of view and display size using an Asheville, North Carolina, synthetic vision database and fixed-based simulator. The second experiment was conducted on the NASA B-757 aircraft at Dallas/Fort Worth International Airport and investigated the efficacy of both head-down and head-up displays and generic and photorealistic terrain texture. Both experiments confirmed the retrofit capability and that all sizes and texturing methods were found to be viable candidates for synthetic vision displays. These results, future directions, and implications for meeting national aeronautic safety and capacity goals are discussed.

The effectiveness of three different data link interfaces, involving auditory, visual, and redundant presentation of Air Traffic Control (ATC) information, was evaluated in a single pilot general aviation simulator. Fifteen certified flight instructor pilots flew a Frasca flight simulator with full visual display of the outside world, through a series of ATC-instructed maneuvers, while scanning outside for traffic. ATC instructions, of various lengths, were delivered through a text based data link display, through synthesized voice (similar to the current system), or through a redundant voice-text format. Pilots read back the instructions and then complied with whatever maneuver was instructed, while monitoring for traffic. Visual scanning was measured. The results revealed that the visual display provided greatest accuracy of communications readback, and was least disruptive of both traffic monitoring and flight path tracking. The auditory-only condition was most disruptive of these tasks, in part becaus...

The vehicle display condition must be adapted to the visual characteristics of elderly people, because increasing elderly drivers are expected. In this study, the measurements of two visual characteristics were found–visual acuity for distance and muddiness of crystalline lens, and the effect on display condition due to visual characteristics was investigated. The results show that the display condition for elderly people should be as follows. The size of characters is extended. The luminance level in night conditions has a widely a adjustable level, and in daytime conditions is set at similar or slightly higher levels in comparison with young and middle aged drivers.

Thirty-six pilots (31 men, 5 women) were tested in a flight simulator on their ability to intercept a pathway depicted on a highway-in-the-sky (HITS) display. While intercepting and flying the pathway, pilots were required to watch for traffic outside the cockpit. Additionally, pilots were tested on their awareness of speed, altitude, and heading during the flight. Results indicated that the presence of a flight guidance cue significantly improved flight path awareness while intercepting the pathway, but significant practice effects suggest that a guidance cue might be unnecessary if pilots are given proper training. The amount of time spent looking outside the cockpit while using the HITS display was significantly less than when using conventional aircraft instruments. Additionally, awareness of flight information present on the HITS display was poor. Actual or potential applications of this research include guidance for the development of perspective flight display standards and as a basis for flight training requirements.

The effects of two types of vision enhancement system (VES) displays on younger- and older-driver performance were systematically examined in various contexts. Younger and older drivers used either a conformal or a nonconformal VES display while driving in a fixed-base driving simulator. Within each block of trials, traffic scenarios were used to test driver performance: everyday driving, intersection approaches, emergency events, and VES failure. Conformal imagery directly highlighted aspects of the traffic environment, whereas nonconformal displays were coupled to environmental events but not superimposed on them. In all driving scenarios, conformal displays had a performance advantage over nonconformal displays. These advantages, however, depended on what was highlighted and whether a highlight covered or obscured important information about the environment. The perceived benefits of VESs are in situations where visibility is limited by weather (e.g., fog, snow, or rain), time of day (e.g., night or dusk), or roadway geometry (e.g., curves or railway crossings). Implications of the results for the design of conformal and nonconformal VESs and for future research are discussed.

This study compared the effect of alternative graphic or numeric vertical navigation aircraft cockpit displays on horizontal and vertical flight technical error, workload, and subjective preference. Displays included (a) a moving map with altitude range arc; (b) the same format, supplemented with a push-to-see profile view, including a vector flight-path predictor; (c) an equivalent numeric display; and (d) a numeric nonvertical navigation display. Sixteen pilots each flew 4 different approaches with each format in a Frasca 242 simulator. Our vertical navigation displays reduced vertical flight technical error by as much as a factor of 2 without increasing workload. Relative advantages of the graphics formats are discussed.

Sixteen younger and 16 older drivers participated in this simulated driving experiment. They were instructed to perform a push button task and a navigation task while using the displayed traffic information to drive through each scenario. The Advanced Traveler Information (ATI) was presented visually only, aurally only, or by multi-modality display. All drivers made significantly fewer errors in responding to hazard warnings when using multi-modality and auditory displays compared to visual-only displays. When the ATI system presented complex information, multi-modality display led to significantly faster and more accurate recognition of hazards and better control of car direction and speed. The results indicate that multi-modality display of ATI is optimal, particularly for older drivers.

Three prototype displays are contrasted for aircraft navigation and tactical hazard awareness: a conventional 2-D coplanar display, an exocentric (God's eye) 3-D display, and an immersed (pilot's eye) 3-D display coupled with a small scale global display. Strengths and weaknesses of each display type are discussed, related particularly to the ambiguity of perspective displays and to attention allocation problems with dual-display suites. In Experiment 1, 8 pilots flew with each of the displays around an airspace populated by waypoints, hazards, and traffic. Performance measures revealed the anticipated costs and benefits of each display type. In Experiment 2, cognitive engineering techniques of performance and cognitive task analysis were applied to remediate the weaknesses of each display type. Emphasis was placed on display enhancements to resolve 3-D ambiguity and visual momentum and cueing techniques to facilitate attention allocation and switching. Analysis of performance of 27 additional participant...

In 2 experiments we describe the relevance of aircraft predictor information to the availability and deployment of visual attention. In both, airplane pilots fly a simulator in which flight path prediction is given bearing on the future state of their own aircraft and of a second traffic "intruder" aircraft that they must maneuver to avoid. The cockpit traffic display on which this information is depicted is an integral component of the concept of free flight or pilot self-separation. In Experiment 1 we show that added layers of predictive information improve performance, reduce mental workload (as subjectively measured), and that added complexity of the visual display thus resulting does not increase the inferred measure of head downtime (secondary-task performance). In Experiment 2 we examine the consequences to performance and visual attention if prediction is occasionally in error. We adopt the hypothesis that trust is related to the relative allocation of attention between the predictor symbol and the raw data of actual aircraft state. Such unreliability damages performance to some extent, particularly when the unreliable predictor forecasts more complex conflict geometry. This cost reveals the substantial allocation of attention to the predictor symbol. However, pilots, knowing the level of unreliability, appear to be relatively well calibrated in their allocation of attention between the 2 information sources.

A simulation study was performed to evaluate helmet-mounted display symbology for fighter aircraft ground collision avoidance systems. Four visual alert symbologies were tested: an iconic cue, an aircraft-fixed (AF) guidance cue, a head-fixed (HF) guidance cue, and an HF guidance cue with a pitch ladder. Participants were given audio and visual side tasks and responded to alerts in different aircraft attitudes. Shorter reaction times were observed when a HF visual alert was given in addition to the standard audio alert. No significant differences in recovery performance (measured by response time and altitude loss) were observed between display formats. However, the display format had a significant effect on participant head motion. With HF guidance cues, pilots were able to perform the recovery maneuver with their heads off axis; with AF guidance cues or no guidance cues, pilots consistently turned their heads to face forward before maneuvering the aircraft.

Maintaining lane position during low-visibility conditions can be a challenge for snowplow operators. Providing continuous and accurate lane position information to complement existing roadway cues may be the solution to increasing driver awareness. The first phase of a systemsbased approach to designing the operator interface for a snowplow lane tracking system is described. Through a systems-based approach, not only can the type of controls and displays to use for the operator interface be better defined, but the interface’s role and the amount, type, and presentation of information can be determined. In this first phase, ridealong interviews and an operator survey were used to identify factors affecting forward visibility and lane position in snowplow operations. More than 1,000 department of transportation snowplow operators from Iowa and Minnesota completed the survey. Ride-along drives showed that operators frequently lose sight of the forward roadway for brief periods and use several cues to adjust the lane position of their vehicles. Survey findings indicated that center and shoulder lines are helpful and intuitive cues for left- and right-wing plow operations. Additional findings suggest that operators need a flexible system that enables them to adjust alarm thresholds and that the operator interface should be designed as an aid rather than as a primary display. Because drivers do not have the visual resources for a dedicated display, a peripheral visual or haptic (tactile) display could be used to complement existing roadway cues.

Thirty-six participants were tested on their ability to orient toward the nearest airport based on the manner in which information was presented on a global positioning system (GPS) area navigation display. Results indicated that use of the tabular, text-only format normally found on such displays was significantly slower and less accurate than either a map display of nearest airport information or a text display that included an orientation symbol. Additionally, pilots ignored information from the heading indicator, focusing on the GPS to perform the task. Discussion focuses on the need to support pilot decision making.

The study used a vehicle-based driving simulator to evaluate two graphical displays, one showing risk probability in terms of safety margin (Time Headway, TH), and one showing risk severity in terms of Kinetic Energy (KE). Twenty-seven subjects were randomly allocated to one of three experimental conditions: Control, TH, and KE. Subjects undertook three driving tasks (ABA design). For the second driving task in the TH and KE conditions, subjects drove in the presence of their respective feedback displays. Measures of TH and KE levels were taken, as well as subjective measures of risk and task loading. It was found that the KE display was more effective than the TH display in reducing the proportion of time subjects spent at short headways. The KE display was also effective in reducing the proportion of time subjects spent at high speed. The KE display appeared to affect the perception of risk (severity of potential accidents). It was concluded that further research evaluating displays that combined the positive effects of both parameters within a single representation display is needed.

It has been established that head-down displays (HDDs), such as those commonly placed in the dashboard of commercial automobiles, can draw drivers’ attention away from the primary driving task (Bach et al., 2008). This problem can be exacerbated when screens are “busy” with graphics or rich information. In this paper, we present the results of a driving simulator-based user study where we examined two potential alternatives to HDDs for presenting textual lists. Subjects conducted a series of street name finding tasks using each of three system variants: one with a HDD, one with a head-up display (HUD), and one with only an auditory display. We found that the auditory display had the least impact on mental load, but at the expense of task completion efficiency. The HUD variant also had a low impact on mental load and scored highest in user satisfaction, and therefore appears to be the most viable target for future study.

One of the aspects that cause an interactive vehicle simulator to differ from the real system is delay in the visual display. Because of this delay, the person in the simulator receives visual feedback of his control actions slightly later when compared with the real system, which can reduce the task performance. Compensation techniques can be applied to reduce the effects of delay. This article describes an algorithm that was implemented in a driving simulator for this purpose. Two experiments were carried out, in which subjects drove the simulator with and without compensation, to evaluate its effect on task performance and control effort. The results show that the display delay is counterbalanced by the compensation in an effective and efficient manner: when using the compensation, driving behaviour in the simulator has a better resemblance to that in the real vehicle.

Eight vehicles equipped with an autonomous Route Guidance System (RGS) were deployed in two geographical areas for a field test. The RGS provided the driver with turn-by-turn instructions to a selected destination using graphics presented on a monochromatic screen and verbal instructions through a dedicated speaker. Each of 45 participants drove a vehicle for approximately one month and reported their experiences in a post-drive debriefing. The debriefing consisted of both a questionnaire and a structured interview. The emphasis of the field test was to evaluate the driver interface. The results indicated that the participants were generally satisfied with the performance and usefulness of this implementation of a route guidance system. They liked the accuracy of the system and the ease of guidance to destinations. Implications for future system design improvements are discussed.

A sequential or RAP COM (rapid communication) display was compared with a more conventional spatial display as participants monitored dynamically changing sets of three-digit numbers and responded to occasional target stimuli. In an effort to equate the stimulus-response compatibility of the two displays, we had participants respond to the targets with a chord keyboard in Experiment 1 and vocally in Experiment 2. We examined the influence of display duration on performance with the RAP COM and spatial formats by presenting stimuli at three different durations (400, 800, and 1200 ms). The influence of practice on performance with the RAP COM and spatial displays was also investigated. Participants responded to targets more quickly in the RAP COM than in the spatial displays at each of the three presentation durations and across more than 2000 trials of practice. Accuracy was influenced by the display presentation duration. Accuracy was higher for the RAP COM than for the spatial display at the 800-ms stimulus presentation duration in Experiment 1 and at the 800- and 1200-ms presentation durations in Experiment 2. The results are discussed in terms of the potential utility of RAP COM displays for complex, real-world systems.

Interface design is an important factor in assessing the potential effects on safety of interacting with an in-vehicle information system while driving. In the current study, the layout of information on a visual display was manipulated to explore its effect on driving performance in the context of music selection. The comparative effects of an auditory-verbal (cognitive) task were also explored. The driving performance of 30 participants was assessed under both baseline and dual task conditions using the Lane Change Test. Concurrent completion of the music selection task with driving resulted in significant impairment to lateral driving performance (mean lane deviation and percentage of correct lane changes) relative to the baseline, and significantly greater mean lane deviation relative to the combined driving and the cognitive task condition. The magnitude of these effects on driving performance was independent of layout concept, although significant differences in subjective workload estimates and performance on the music selection task across layout concepts highlights that potential uncertainty regarding design use as conveyed through layout concept could be disadvantageous. The implications of these results for interface design and safety are discussed.

This study was designed to investigate effects of different display configuration designs. Nineteen drivers completed a driving simulator study designed to resemble normal driving. Driving performance, glance behaviour, physiological measures, and task completion times was measured for two display configuration designs both during driving only and during driving with a simple secondary task, which consisted of detection, and off-setting of presented warnings. The display configuration design with more centrally placed information, e.g. the HUD and HDD, had less detrimental effects on driving performance and glance behaviour. The physiological measures showed, however, no significant differences between display configuration designs.

Polygon displays compress information that would otherwise be conveyed by separate indicators into a single display in which each reading is represented by the distance of a polygon vertex from its center. The effect on detection of fault states of varying the number of polygon vertices from 4 to 20 in a display presented peripherally around a dynamic, simulated flight display was studied. Presence of the dynamic task reduced both speed and accuracy of response to the polygon display but did not significantly affect the pattern of response to differing numbers of vertices. All measures of performance were better with larger numbers of vertices. If the vertices are processed serially, more vertices require more processing time. Therefore, the result argues for holistic processing and implies that such information integration is beneficial to human performance in fault detection.

Advanced driver assistance systems (ADAS) can be designed to adapt to the driver's current needs, for example, taking the traffic conditions in the immediate vicinity of the ego vehicle into account. This motivates the design of a system intended to measure the local traffic conditions in a way, which corresponds to the driver's perception of traffic conditions. A new method of measurement is introduced. It is based on automotive sensor technology. A stochastic approach is employed to optimise and evaluate the relationship between the subjective measurements made by the driver and the objective measurements presented. To this end, the drivers' subjective ratings are taken as reference. The analysis presented here is based on simulation data. The outcomes show that the design of the developed simulation environment is applicable to this work. It is shown that the objective measures correspond to the driver's subjective ratings. Thus, it is possible to estimate the driver's perception of traffic conditions using a technical measurement. The algorithm in its presented form is appropriate to give an estimation, which can be used as an input parameter for ADAS.

OBJECTIVE: This experiment attempted to identify the features of air traffic geometry that would influence the difficulty and biases of pilots' conflict detection using a cockpit display of traffic information (CDTI). BACKGROUND: There was previously no systematic study on effects of such features on conflict detection using the CDTI. METHOD: Twenty-four pilots viewed dynamic encounters between their own aircraft and an intruder aircraft on a simulated CDTI; difficulty was varied by the intruder aircraft's distance and time to closest point of approach (CPA), relative speed, miss distance at CPA, approach side, and conflict angle. Participants estimated the intruder's location at, and its time to, CPA. Effects on three estimation error measures were explored: intruder's miss distance at CPA, orientation at CPA, and time to CPA. RESULTS: (a) Estimation errors increased with slower speeds, longer times to CPA, and longer distances to CPA and with longer miss distances at CPA; (b) the best performance occurred at a conflict angle of 90 degrees; (c) there was a bias to judge conflicts to be more risky than was actually the case; and (d) there was a "distance-over-speed" bias, such that two aircraft farther apart and converging rapidly were perceived as less risky than when they were closer to each other and converging at a slower rate, despite identical time to CPA. CONCLUSION: Pilots' conflict detection with CDTI was subject to various errors and biases, which has important safety implications. APPLICATION: The design of procedures, displays, and decision support tools for the free flight environment needs to take these human performance limitations into account. Language: en

This paper reports on a study of the effect of headway displays on driver following behavior. A visual color display, mounted in the instrument panel, was designed to indicate to drivers whether the headway they maintained was appropriate for the vehicle speed. Various human factors issues concerning the design and development of a headway display, are experimentally addressed.

Using an in-car instrumentation may sometimes even conflict with driving requirements. Drivers can easily solve such problems provided designers have taken the necessary precautions by providing for optimum display location, and clear organization, and by allowing good legibility in all conditions of illumination. The purpose of the present paper is to list the required standards and identify the gaps to be filled in by appropriate research.

This paper describes a 2–1/2 year project concerning human factors and future driver-information systems. The project goals are to (1) develop human factors guidelines, (2) devise test methods for safety and ease of use, and (3) develop a model that predicts driver performance when using these systems. A literature review has been completed and focus groups that identified driver needs have been conducted. In addition, a method was developed to select the most beneficial systems using accident reduction, congestion relief, and driver needs/wants as the criteria. Consequently, car phones, navigation, traffic information, vehicle monitoring, and hazard warning systems were selected for further study. Preliminary versions of each have been designed and laboratory tests are in progress. Usability tests in a driving simulator and on the road are scheduled.

A survey was distributed and an experiment was performed to analyze two air traffic control (ATC) color-coded display formats: (1) the currently used plan view display format, and (2) a perspective display format. The results of both the survey and experiment were used to extract specific user requirements from which specifications could be applied to design a three-dimensional, dynamic, color-coded, perspective display for use in an ATC environment. The emphasis of the survey and current experiment focused on the air traffic controller's point of view in terms of cognitive workloads, task and information requirements, color preferences, and air traffic workloads relative to traffic density and complexity. Fifteen full-performance air traffic controllers performed three timed tasks: (1) resolve impending air traffic conflicts, (2) identify the callsigns of aircraft in the highest and lowest actual altitudes, and (3) reconstruct air traffic situations. Two levels of traffic density were crossed with two display types for six different ATC scenarios. The results indicated that for the conflict resolution task performance was faster for the perspective display format only in the lower density level, and performance was the same for both display types in the higher density level. Performance for altitude extraction task for both density levels was faster for the perspective display format than for the plan view display format. Performance was the same for the reconstruction task for both display types and both density levels. Finally, performance was faster for the conflict resolution task than for the altitude extraction task across both display types and both density levels.

This paper presents a cognitive analysis of a pilot's navigation task and describes an experiment comparing a new map display that employs the principle of visual momentum with the two traditional approaches, track-up and north-up. The data show that the advantage of a track-up alignment is its congruence with the egocentered forward view; however, the inconsistency of the rotating display hinders development of a cognitive map. The stability of a north-up alignment aids the acquisition of a cognitive map, but there is a cost associated with the mental rotation of the display to a track-up alignment for tasks involving the ego-centered forward view. The data also show that the visual momentum design captures the benefits and reduces the costs associated with the two traditional approaches.

In the first part of the reported research, 12 instrument-rated pilots flew a highfidelity simulation, in which air traffic control presentation of auditory (voice) information regarding traffic and flight parameters was compared with advanced display technology presentation of equivalent information regarding traffic (cockpit display of traffic information) and flight parameters (data link display). Redundant combinations were also examined while pilots flew the aircraft simulation, monitored for outside traffic, and read back communications messages. The data suggested a modest cost for visual presentation over auditory presentation, a cost mediated by head-down visual scanning, and no benefit for redundant presentation. The effects in Part 1 were modeled by multiple-resource and preemption models of divided attention. In the second part of the research, visual scanning in all conditions was fit by an expected value model of selective attention derived from a previous experiment. This model accounted for 94% of the variance in the scanning data and 90% of the variance in a second validation experiment. Actual or potential applications of this research include guidance on choosing the appropriate modality for presenting in-cockpit information and understanding task strategies induced by introducing new aviation technology.

The Nara Prefectural Police HQ developed and began operating a traffic movement display system. Unlike the conventional method of traffic condition display on a wall map which extracts traffic volume or flow data in time series and expresses its changing conditions from moment to moment as a quantity, this new system enables the spatiotemporally continuous expression of traffic volume or traffic flow. This paper introduces the traffic movement display system which is considered to be an effective means for an intelligent transport system (ITS) and discusses its applications to the wall map display including the identification and display of specific vehicles such as buses and trucks by making the best use of this system of information obtainable from infrared beacons which also perform a part of the ITS.

A vehicle-based data collection system is explored. It is capable of gathering accurate data on the relative movements of adjacent vehicles, and hence driver behavior, in a traffic stream. The instrumented vehicle may support a variety of detection devices, for example a tracking laser rangefinder head, or a constantly scanning laser beam (a LIDAR). To relate the measurements to the position of the vehicles on the road, several sub-systems are devised to calculate corrections required by variations in steering, and vibrational movements caused by the road surface. Operational specifications of the vehicle are devised, in terms of road and traffic conditions required for optimum performance, and strategies for use.

The paper first discusses using HUDs for in-vehicle navigation/route guidance systems based on the results of preliminary experiments. It then discusses how and what kinds of information should be displayed by HUDs to assure ease of recognition by the driver. Finally, based on these considerations, a HUD system is proposed as a visual interface for future in-vehicle navigation/route guidance systems. >