Perception of Oncoming Vehicle Time-to-Arrival

Abstract

An experiment was conducted in a fixed-base driving simulator which manipulated the time-to-arrival (Ta) of an oncoming vehicle, the viewing distance to that vehicle and the type of oncoming vehicle to determine the perceptual basis for a left-turn decision. Forty-eight participants were randomly assigned to a group where either a motorcycle, a compact car, a full-size car, or delivery truck represented the oncoming vehicle. There were an equal number of participants of each gender in the four groups. As Ta was increased, underestimation of vehicle arrival time also increased. Significant main effects were found for Ta, gender of participants, vehicle type, and viewing distance, and for interactions for gender x Ta and gender x vehicle type. Males and females differed in their accuracy of judgments for vehicle types, where males were more accurate in estimating the arrival of delivery vans and motorcycles than their female peers. The pattern of results for the size of the approach vehicle were consistent with a margin-of-safety explanation which argues that driver underestimation of the arrival times of larger vehicles generally allows larger margins-of-safety than for smaller vehicles. The importance of these findings for the development of advanced in-vehicle collision avoidance and warning systems is briefly considered.