Safety assessment of a rear-end crash avoidance system.

This paper assesses the safety impact of an automotive collision avoidance system (ACAS) at three levels: exposure and response to driving conflicts, involvement in severe near-crashes, and unintended consequences. The ACAS performs forward crash warning and adaptive cruise control functions. The safety assessment is based on objective data collected from a field operational test by sixty-six volunteers who drove ten equipped vehicles on public roads over 158,000 km. This paper focuses on estimating the safety benefits of this integrated system based on driver exposure and response todriving conflicts, with and without ACAS assistance. Generally, the ACAS reduced driver exposure to lead-vehicle-decelerating and lead-vehicle-stopped conflicts at speeds greater than or equal to 56 km/h. Moreover, the ACAS has the potential to prevent between 133,000 (3%) and 1,039,000 (26%) rear-end crashes annually in the United States if fully deployed in the light vehicle fleet (e.g., passenger cars, vans, minivans, sport utility vehicles, and light trucks). For the covering abstract see ITRD E134653.