Avinoam Borowsky

Drivers’ perception of vulnerable road users: A hazard perception approach

The present study examined how experienced and young-inexperienced drivers (either trained in hazard perception or not) respond to and identify pedestrians when they appear in residential roads within populated neighborhoods and in urban roads located outside neighborhoods and usually less populated. As part of a hazard perception test, participants were connected to an eye tracking system and were asked to observe 58 traffic scene movies and press a response button each time they detected a hazardous situation. Analyzing all pedestrian-related events revealed that, regardless of driving experience or training, drivers detect pedestrians less often when they appear in urban areas and more often when they appear in residential areas. Moreover, experienced drivers processed information more efficiently than young-inexperienced drivers (both trained and untrained) when pedestrians were identified. Visual search patterns in urban and residential traffic environments are discussed.

Formation and Evaluation of Act and Anticipate Hazard Perception Training (AAHPT) Intervention for Young Novice Drivers

Objective: Young novice drivers’ poor hazard perception (HP) skills are a prominent cause for their overinvolvement in traffic crashes. HP, the ability to read the road and anticipate forthcoming events, is receptive to training. This study explored the formation and evaluation of a new HP training intervention—the Act and Anticipate Hazard Perception Training (AAHPT), which is based upon exposing young novice drivers to a vast array of actual traffic hazards, aiming to enhance their ability to anticipate potential hazards during testing. Method: Forty young novices underwent one of 3 AAHPT intervention modes (active, instructional, or hybrid) or a control group. Active members observed video-based traffic scenes and were asked to press a response button each time they detected a hazard. Instructional members underwent a tutorial that included both written material and video-based examples regarding HP. Hybrid members received a condensed theoretical component followed by a succinct active component. Control was presented with a road safety tutorial. Approximately one week later, participants performed a hazard perception test (HPT), during which they observed other movies and pressed a response button each time they detected a hazard. Twenty-one experienced drivers also performed the HPT and served as a gold standard for comparison. Results: Overall, the active and hybrid modes were more aware of potential hazards relative to the control. Conclusions: Inclusion of an active–practical component generates an effective intervention. Using several evaluation measurements aids performance assessment process. Advantages of each of the training methodologies are discussed. Supplemental materials are available for this article. Go to the publishers online edition of Traffic Injury Prevention to view the supplemental file.

The effects of momentary visual disruption on hazard anticipation and awareness in driving.

Objective: Driver distraction is known to increase crash risk, especially when a driver glances inside the vehicle for especially long periods of time. Though it is clear that such glances increase the risk for the driver when looking inside the vehicle, it is less clear how these glances disrupt the ongoing processing of information outside the vehicle once the drivers eyes return to the road. The present study was aimed at exploring the effect of in-vehicle glances on the top-down processes that guide the detection and monitoring of hazards on the forward roadway. Method: Using a driving simulator, 12 participants were monitored with an eye-tracking system while they navigated various hazardous scenarios. Six participants were momentarily interrupted by a visual secondary task (simulating a glance inside the vehicle) prior to the occurrence of a potential hazard and 6 were not. Results: Eye movement analyses showed that interrupted drivers often failed to continue scanning for a potential hazard when their forward view reappeared, especially when the potential threat could not easily be localized. Additionally, drivers’ self-appraisal of workload and performance of the driving task indicated that, contrary to what one might expect, drivers in the interruption condition reported workload levels lower than and performance equal to drivers in the no interruption condition. Conclusions: Drivers who are momentarily disrupted even for a brief duration are at risk of missing important information when they return their gaze to the forward roadway. In addition, because they are not aware of missing this information they are likely to continue engaging in in-vehicle tasks even though they are demonstrably unsafe. The implications for safety, calibration, and targeted remediation are discussed.

Driving Speed of Young Novice and Experienced Drivers in Simulated Hazard Anticipation Scenes

Objective: In this study, we aimed to demonstrate analysis methods that are sensitive to speed-related differences between experienced and young novice drivers. These differences may be linked to determining which group is better at anticipating hazards. Background: Awareness of hazardous situations, especially potential ones, is a major discriminator between experienced and young novice drivers who tend to misidentify potential hazards in the traffic environment. Method: Experienced and young novice drivers were asked to drive a sequence of 14 scenarios in a driving simulator. Scenarios were created in two city areas, residential and business district, and included various types of hazards. Group homogeneity of speed for each group of drivers was computed for each scenario, and two business district scenarios were subjected to piecewise linear regression analysis. Results: Group homogeneity analysis showed consistent and significant experience-based differences across all scenarios, revealing that the experienced drivers as a group were more homogenous in choosing their driving speed. Differences between groups were larger in the business district where speed was less restricted. Piecewise linear regression analysis revealed that experienced drivers approached uncontrolled intersections by slowing down and responded earlier to materialized events. Conclusion: Young novice drivers were more likely than experienced drivers to choose diverse values of speed at any given road section, presumably due to their poor awareness of potential and hidden hazards. Unlike other analysis methods, it is argued that group homogeneity of speed is a more sensitive measurement to reveal these gaps. Application: Speed management could be the basis of future hazard anticipation simulator assessments.

Is More Information Better? How Dismounted Soldiers Use Video Feed From Unmanned Vehicles: Attention Allocation and Information Extraction Considerations

Operational tactics in urban areas are often aided by information from unmanned aerial vehicles (UAVs). A major challenge for dismounted soldiers, particularly in urban environments, is to understand the conflict area in general and particularly from the UAV feed. The UAV feed is usually used to enhance soldiers’ situation awareness abilities but less for identifying specific elements. A possible way to further enhance soldiers’ abilities is to provide them with multiple sources of information (e.g., aerial and ground views). This study examined the benefits of presenting video feed from UAVs and unmanned ground vehicles (UGVs) in a combined interface, relative to presenting aerial feed alone. Thirty former infantry soldiers with no experience in operating unmanned vehicles participated. Objective performance, subjective evaluations, and eye-tracking patterns were examined in two scenarios. In Scenario 1, performance scores in both identification and orientation tasks were superior in the combined configuration. In Scenario 2, performance scores in the identification tasks were improved, and the addition of the UGV feed did not harm performance in the orientation task. Eye movement scanning patterns reinforced that both UAV and UGV feeds were used for the mission. The combined configuration generated consistent benefits with regard to the identification tasks, perceived mental demand, and reduction of false reports without having any apparent cost on participants. Ground views may provide additional support to dismounted soldiers.

Minimum Time to Situation Awareness in Scenarios Involving Transfer of Control from an Automated Driving Suite

This research assessed the impact of vehicle automation on a driver’s ability to anticipate latent threats and to detect materialized hazards on the forward roadway. In particular, the minimum alert time before transfer of control was determined. This was the minimum time required after an autonomous driving suite (ADS) had been in full control of a vehicle for the driver to reacquire the same level of situation awareness that he or she had when in full control of the vehicle. This simulator study included five treatment conditions during which drivers either were always in complete control of their own vehicle (control) or were required to resume control at 4 s, 6 s, 8 s, or 12 s before the appearance of a latent hazard (transfer). While the vehicle was in autonomous mode, the drivers performed an in-vehicle task for more than a minute and were told not to glance at the forward roadway. Analysis of eye movements showed that drivers in the control condition detected nearly 40% more hazards compared with drivers in the shortest transfer condition. The results indicated how long before control was transferred from the ADS back to a driver that the driver should be told that a transfer would occur, if the driver were to have full situation awareness. Unlike previous studies, this study both ensured that the driver was not watching for hazards while the ADS was in control and used a measure of situation awareness (hazard anticipation) that was closely linked to the actual understanding a driver had of the threats present in a given scenario.

Experienced drivers are quicker to achieve situation awareness than inexperienced drivers in situations of transfer of control within a Level 3 autonomous environment

Previous researchers examining transfers of control from semi-autonomous to manual driving have found that younger drivers engaged in a secondary task while in automated mode need at least 8 seconds to achieve the same level of situation awareness as drivers always in control of their vehicle (Samuel et al., 2016). It is likely that middle-age drivers, with their increased driving experience would require less time. To test this hypothesis, middle-age drivers participated in a driving simulator experiment where they were asked to either drive manually (control) or with a simulated autonomous system (experimental conditions). While in automated mode, drivers either received an alert 4s, 6s, 8s, or 12s prior to the presence of a latent hazard. The proportion of latent hazards anticipated was examined. The results were consistent with the hypothesis that middle-age drivers were better at anticipating hazards overall and were faster to achieve appropriate situation awareness associated with manual driving than younger drivers.

Evaluation of Training Interventions to Mitigate Effects of Fatigue and Sleepiness on Driving Performance

Fatigue and sleepiness are leading contributors to road crashes. Either can occur in the evening, sometime around 10:00 p.m., after a day that begins in the morning, sometime around 8:00 a.m. Other factors contribute as well to performance decrements in the evening for those who regularly work during the day. It is arguably the case that these various factors are responsible for the observed decrements in safety-critical driving skills, such as hazard anticipation, hazard mitigation, and attention maintenance, which occur in the evening. However, it is by no means clear whether a training program can be designed to mitigate the effects that such factors have on these critical driving skills. A simulator experiment was undertaken to determine whether a training program [sleepiness and fatigue evaluation training (SAFE-T)] could lead to improvements in the hazard anticipation, hazard mitigation, and attention maintenance skills of drivers who had been awake for 12 h. The results showed that for all three skills trained drivers performed significantly better during the posttest (after SAFE-T) than the pretest (before SAFE-T), whereas the placebo drivers performed significantly worse during the posttest than the pretest. Fatigue and sleepiness both increased during the posttest from their pretest values. Thus the effects of training are still observed even in the presence of increases in fatigue and sleepiness.

Where do older pedestrians glance before deciding to cross a simulated two-lane road? A pedestrian simulator paradigm

Knowing where to older pedestrians allocate their glances before deciding to cross the road can contribute to understanding the causes that lead them to make bad road crossing decisions. Research on older drivers suggest that they are over involved in crashes that involve navigation through intersections mainly because they focused on their travel path and rarely on other areas in the scene from where a hazard might appear. Yet, it is less known how older pedestrians spread their attention on their expected travel path. Eleven older participants (over 65) and ten younger adults were asked to make a road crossing decision in a simulated environment, while wearing an eye-tracker. Results exemplify significant differences between the younger and older adults; the older adults, in comparison to the younger, spent more time focusing on the central area of the scene and even less so in the last five seconds before making the crossing decision. These findings are consistent with older drivers’ behavior at intersections, suggesting that older pedestrians might be overly focused on their travel path.

The use of a homogeneity measure to identify hazard perception abilities of novices and experienced drivers in a driving simulator

Comparisons between young-novice and experienced drivers are beneficial for the development of both testing and training methodologies for young-novice drivers. Simulators are essential tools of driver assessment especially for novices. One way to look at the differences between driver groups is by examination of performance with regard to specific events. In addition, overall examination of performance across scenarios is important as it shows general patterns of behavior rather than specific ones. The common method to do so is by looking at the average of certain driving related measures or their variability. Using data derived from two hazard perception test (HPT) experiments in a driving simulator, we demonstrate how the use of a group homogeneity measure is more sensitive than the former two. Altogether, we demonstrate that consistently and regardless of road environment, experienced drivers manage their speed in a more homogenous way while novices act as inconsistent individuals.