Commercial Motor Vehicle Driver Performance with Adaptive Cruise Control in Adverse Weather

The purpose of this study was to investigate how commercial motor vehicle (CMV) drivers’ performance with adaptive cruise control (ACC) was affected by weather conditions. The study analyzed 33,000 hours of naturalistic data across 78 CMV drivers throughout the United States. It was found that drivers set their ACC speed to an average of 63 m/h, regardless of weather conditions. It was also found that users of one brand ACC allowed the system to control the headway of the vehicle for 7.4% of the time in adverse weather compared to 6.0% of the time in non-adverse conditions. Finally, the study found that the mean headway in adverse conditions was longer using ACC compared to manual driving across both brands ACC. Manufacturers of ACC systems do not recommend their use in adverse conditions, and their observed use in this study indicates their performance in adverse weather needs to be better understood.