Driver distraction, warning algorithm parameters, and driver response to imminent rear-end collisions in a high-fidelity driving simulator.

This report presents three experiments that use a high fidelity driving simulator to examine driver response to imminent rear-end collision situations. The first experiment examines how variations in algorithm parameters affect the ability of a Rear end Collision Avoidance System (RECAS) to aid distracted drivers in avoiding an imminent collision. The results show that an early warning helps drivers to react more quickly and to avoid more collisions than either a late warning or no warning. The second experiment examines the ability of the RECAS to help non-distracted driver avoid an imminent collision. The results show that the RECAS benefits drivers even when they are not distracted. The third study examines the effect of manipulating the urgency of the auditory warning by changing the volume of the warning tone. Varying the volume levels for the warning tones had no systematic effect on the driver response. These studies show that the RECAS provides a potential safety benefit by reducing the time it takes drivers to remove their foot from the accelerator. The warnings do not speed the drivers' application of the brake, increase their maximum deceleration, or affect their mean deceleration. (Author/publisher)