An Analysis of Driver's Behaviour during the System Limits (A Study Regarding the Warning Timing of System Limits for the Designing of Low Speed Adaptive Cruise Control Systems)

Abstract

We analyzed the driver's braking behavior during the system-limit-warning, meaning the system is inevitable to avoid the collision on the preceding vehicle, when the driver was using Low Speed Adaptive Cruise Control. It was observed that the drivers are judging the condition of system-limits, not only by themselves but also by the system-limit-warning. Driver's braking behavior was delayed when the assumed delay time was set at less than 1.2 s in the Stopping Distance Algorithm. We also analyzed the driver's braking behavior in the miss warning condition. Driver's braking behavior during the miss warning was extremely delayed when the assumed delay time was set at less than 1.0 s. In the designing of warning timing by use of Stopping Distance Algorithm, one of the optimal warning timing is 1.2s, when we focus on not only the normal condition that the warning system operate accurately but also the miss warning condition.