Using Insurance Claims Data to Evaluate the Collision-Avoidance and Crash-Mitigating Effects of Collision Warning and Brake Support Combined with Adaptive Cruise Control

Cars are increasingly equipped with functions that protect drivers from crashes. Forward Collision Warning and Brake Support combined with Adaptive Cruise Control (CWB+ACC) are collision-avoidance features available in modern cars. Previous real-world evaluations have reported on the crash-avoidance performance of these technologies. The objective of this study was to evaluate the safety effect of CWB+ACC in terms of crashes mitigated by reduced impact speed, as well as crashes avoided. The typical conflict situation addressed by the systems is a rear-end frontal collision, i.e. a collision with a vehicle in front of the subject car that is positioned in, or traveling along, the same path. Car-to-pedestrian and car-to-cyclist crashes are also addressed by these systems. For CWB+ACC cars, rear-end frontal collisions were reduced by 37%. A clear mitigating effect was found for different crash-severity levels, and the average number of spare parts used was reduced for CWB+ACC cars. No significant reduction of injured occupants was found for CWB+ACC cars (in striking or struck vehicles). Although an extensive dataset was used for the analysis, there were not enough car-to-pedestrian or car-tocyclist crashes available to obtain a statistically significant analysis of these events.