Out-of-vehicle distractions were identified as contributing factors to about 29.4 % of all crashes that were reported between the years 1995 to 1999 (Stutts J. K., 2005; Stutts J. R., 2001).These crash statistics are from a decade ago. With the increase of cars, pedestrians, shops,vendors, billboards and signs over the last decade it can be safely assumed that the driving environment is more complex now and has greater potential for external driver distraction. Given this, it is important to know the effects of out-of-vehicle distraction on drivers’ ability to drive safely in their presence. With this in mind, a driving simulator study was conducted that compared younger novice and older experienced drivers on their ability to maintain their attention on the forward roadway, anticipate potential hazards and maintain vehicle control while performing an out-of-vehicle tasks. The results of the experiment indicate that both age groups took equally long glances away from the forward roadway at the out-of-vehicle task and that these long glances away from the forward roadway had a negative effects on the hazard anticipation performance of both age groups. In addition, these long glances away from the forward roadway did have a significantly negative impact on the lane maintainence ability of younger drivers as compared to their experienced counterparts but these long glances away from the forward roadway did not seem to affect the speed maintainence abilities of either group. No matter what the vehicle measures indicate, it is clear that both age groups are at elevated risk of crashing when they are attending to tasks that are outside the vehicle.

A potential factor for curve accidents are anticipatory skills. Horizontal curves have been recognized as a significant safety issue for many years. This study investigates the impact and effectiveness of three curve based perceptual speed calming countermeasures (advanced curve warning signs, chevron sign, and heads-up display(HUD) sign) on drivers’ hazard anticipation and mitigation behavior across both left and right-winding curves, and sharp (radius 200m) and flat (radius 500m) curves. Experimental results show that the speed and lateral control in the horizontal curves differed with respect to curve radii, direction, and the type of countermeasure presented. These differences in behavior are probably due to curve-related disparities, the type of perceptual countermeasure, and the presence of hazard at the apex of the curve. HUD is found to be effective at not only reducing the drivers’ speed in the curve, but also improve the latent hazard anticipation ability of the driver at the apex of the curve. Flat and sharp curves with indications of a safety problem were virtually developed in the simulator as representative as possible without upsetting the simulator’s fidelity. 48 participants were recruited for this study between the age range of 18 and 34, and driving experience range was from 0.25 to 17.75 years.

The current driving simulator study investigates the effect of 2 distinct levels of distraction on a drivers’ situational awareness and latent and inherent hazard anticipation. In this study, rear-end crashes were used as the primary crash configuration to target a specific category of crashes due to distraction. The two types of task load used in the experiment was a cognitive distraction (mock cell-phone task) & visual distraction (I-pad task). Forty-eight young participants aged 18-25 years navigated 8 scenarios each in a mixed subject design with task load (cognitive or visual distraction) as a between-subject variable and the presence/absence of distraction representing the within-subject variable. All participants drove 4 scenarios with a distraction and 4 scenarios without any distraction. Physiological variables in the form of Heart rate and heart rate variability was collected for each participant during the practice drives and after each of the 8 experimental drives. After the completion of each experimental drive, participants were asked to fill up a NASA TLX questionnaire which quantifies the overall task load experienced by giving it a score between 1 and 100, where higher scores translate to higher perceived task load. Eye-movements were also recorded for the proportion of latent and inherent hazards anticipated and mitigated for all participants. Standard vehicle data (velocity, acceleration & lane offset) were also collected from the simulator for each participants’ each drive. Analysis of data showed that there was a significant difference in velocity, lane offset and task load index scores across the 2 groups (between-subject factors). The vehicle data, heart rate data and TLX data was analyzed using Mixed subject ANOVA. There was also a logistic regression model devised which showed significant effects of velocity, lane offset, TLX scores and age on a participants’ hazard anticipation abilities. The findings have a major practical implication in reducing drivers’ risk of fatal, serious or near crashes.

The objective of the current study is to evaluate the use of virtual reality (VR) headsets to measure driving performance. This is desirable because they are several orders of magnitude less expensive and, if validated, could greatly extend the powers of simulation. Out of several possible measures of performance that could be considered for evaluating VR headsets, the current study specifically examines drivers’ latent hazard anticipation behavior both because it has been linked to crashes and because it has been shown to be significantly poorer in young drivers compared to their experienced counterparts in traditional driving simulators and in open road studies. The total time middle-aged drivers spend glancing at a latent hazard and the average duration of each glance was also compared to these same times for younger drivers using a VR headset and fixed-based driving simulator. In a between-subject design, forty-eight participants were equally and randomly assigned to one out of four experimental conditions – two young driver cohorts (18 – 21 years) and two middle-aged driver cohorts (30 – 55 years) navigating either a fixed-based driving simulator or a VR-headset-based simulator. All participants navigated six unique scenarios while their eyes were continually tracked. The proportion of latent hazards anticipated by participants which constituted the primary dependent measure was found to be greater for middle-aged drivers than young drivers across both platforms. Results also indicate that the middle-aged participants glanced longer than their younger counterparts on both platforms at latent hazards, as measured by the total glance duration but had no difference when measured by the average glance duration. Moreover, the difference in the magnitude of performance between middle-aged and younger drivers was the same across the two platforms. There were also no significant differences found for the severity of simulator sickness symptoms across the two platforms. The study provides some justification for the use of virtual reality headsets as a way of understanding drivers’ hazard anticipation behavior.