Abstract
It is a challenging task for people to drive a car to cross a road intersection while avoiding collision with lead and trail vehicles. It has been proposed that drivers’ speed regulation in this task can be explained as they intercept a gap of the train of incoming traffic. This explanation turns the task from an avoidance task to an interception task. It raises a question about the difference between interception of a physical object and interception of a gap; it concerns an ontological issue because a physical object is an entity, but a traffic gap is not. To test this explanation, we asked participants (N = 12) to adjust a car’s speed to cross an intersection in a virtual environment. We manipulated the size of the traffic gap and the time of arrival of the traffic gap at the intersection. In comparison conditions, the traffic gap was replaced with a box with the same dimensions with the traffic gap. The box appeared and moved either alone or between incoming vehicles as the gap appeared. In each trial, the participant initially adjusted the car’s speed to a fixed value while approaching the intersection; then a train of vehicles and/or the box appeared on the other road and approached the intersection; then the participant needed to adjust the car’s speed to pass through the traffic gap or the box while avoiding other vehicles or the two ends of the box. We analyzed participants’ speed regulation and examined whether they used the constant bearing strategy to intercept the traffic gap or the box. We did not find any consistent evidence for it such as a constant bearing angle computed with respect to the interception point of the gap or the box. Participants’ eye movements will be examined and discussed.