Drivers' selected settings for adaptive cruise control (ACC): Implications for long-term use

Adaptive Cruise Control (ACC) is a system that assists drivers on longitudinal control by automatically adjusting the throttle. Users can set the speed and gap setting based on their driving preferences. In this study, drivers' ACC use pattern and selection choices are examined based on their level of experience and geographical location. Experienced ACC users from urban settings in Washington are compared to less urbanized areas in Iowa. Information on novice ACC users were also collected in Washington and compared with experienced ACC users within the same area. The outcomes show that although similar use patterns do exist, there are differences in geographical locations and experience levels that impact drivers' choice of ACC settings. In Iowa, experienced ACC drivers select faster speed and closer time headway distance than drivers in Washington State. This suggests that use of ACC differ given environmental surroundings. Within Washington, experienced ACC users set faster speed, closer time headway distance, and intervened less compared with novice ACC users. This suggests that drivers' behavior may change with greater exposure to ACC, which can provide insights on drivers' automation reliance after extended use.