Collision Avoidance Behavior of Unalerted Drivers Using a Front-to-Rear-End Collision Warning Display on the Iowa Driving Simulator

This study investigated whether drivers who operate a vehicle equipped with a front-to-rear-end collision warning system can avoid crashing when a lead vehicle brakes at its maximum potential (e.g., -0.85 g). Drivers in the experimental condition drove a 1993 General Motors Saturn mounted on the Iowa Driving Simulator’s six-degree-of-freedom motion base. The simulator cab was equipped with a collision warning display that provided a primary auditory warning and secondary visual warning based on a time-to-collision algorithm between the subject’s vehicle and the lead vehicle. Two headway distances were tested (2.7 sec and 3.2 sec). The collision avoidance performance of subject drivers was compared to the behavior of drivers in a baseline condition where no collision warning display was present. Relative to the baseline condition, results indicate that drivers using the collision warning display ( a) showed significantly fewer crashes in the shorter headway condition, ( b) collided with the lead vehicle at significantly slower impact speeds, ( c) released the accelerator significantly faster, and ( d) had longer headways both at accelerator release and brake initiation.