Adaptive cruise control: User differences in urban and rural environments

This study aimed to evaluate the perceived use and safety of Adaptive Cruise Control (ACC), a system that automatically maintains a user-defined headway by controlling vehicle speed. A survey, comparable to that of Dickie and Boyle (2009), was administered to drivers in Washington State who were experienced with ACC. In this paper, urban settings in Iowa are compared to the less urbanized areas of Iowa. The outcomes show that drivers in both states had similar perceptions of ACC usefulness and reliability with high confidence in understanding the controls and feedback of the ACC system. Differences were observed in user's perception of ACC's ability to help avoid a crash. In Iowa, drivers felt that ACC would help avoid crashes even with a vehicle stopped in their lane, while Washington drivers had more neutral responses towards ACC's ability to avoid crashes. In fact, drivers in Washington preferred to maintain a longer following distance when compared to Iowa drivers. This could be indicative of general ACC use in urban settings where there is more exposure to varied traffic conditions and is discussed as part of this paper.