Analysis of Braking Behaviors in Car Following Based on A Performance Index for Approach and Alienation

A new index is proposed to evaluate danger situation in car following based on the hypothesis that drivers are performing approach detection and deciding braking behavior with change of area of a preceding car on the retina. Based on the index, braking behaviors in car following situation is analyzed. The experimental results of a test driver with a real car with constant relative velocity to preceding car show that the braking behaviors can be characterized using the index and the gap. In addition, the results of laboratory experiments using a driving simulator support the results of the real car experiments. We conclude that the drivers' deceleration behavior in moderate danger levels can be characterized well in phase plane of the proposed index and the gap. Furthermore, we also show brake initiation timing can be characterized well based on the index modified by taking preceding car speed into account from the experimental results with a test driver.