Effects of Time-Gap Settings of Adaptive Cruise Control (ACC) on Driver’s Risk Feeling Estimated by the Car-Following Situation

Abstract

The present study aimed to clarify the effects of deceleration of the leading vehicle and time-gap setting of ACC on the driver's subjective risk feeling (RF). We measured the RF toward the deceleration of leading vehicle in the field experiments and proposed a RF model using 1/TTC based on results of the field experiments. Also, we developed a car-following simulation model to simulate the car-following behavior for the driving with the ACC when the leading vehicle decelerates. The car-following simulation model was verified by comparing results of the field experiments with those of the field experiments based on the relationship between 1/TTC and THW. In addition, the driver's risk feeling was examined under various conditions corresponding to results of the car-following simulation using the RF model. It is supposed that these findings are effective in expanding the use of ACC under various road conditions and traffic conditions.