Effects of training on learning and use of an adaptive cruise control system

This study examined the effects of formalized training on driver behavior and understanding of an adaptive cruise control (ACC) system with drivers experienced with ACC. Sixteen participants drove an ACC-equipped vehicle while following a lead vehicle around a test track. Participants completed three laps, each featuring different lead vehicle behaviors, such as making a lane change or stopping at a red light, that test the limitations and capabilities of ACC. Immediately before driving, half of the participants watched a training video describing how the ACC system would respond to these lead vehicle behaviors. Braking behavior and use of ACC was recorded by cameras, and participants’ knowledge of the ACC system limitations was assessed by a pre- and post-test questionnaire. Surprisingly, compared to the participants who did not receive training, those who did receive training showed significantly more use of the brake versus allowing the ACC to slow or stop the vehicle for them during certain conditions. We did not observe significant differences between the two groups in time spent using ACC, though participants who did not receive training tended to re-engage ACC more often following automatic deactivation when the system reached its limits than those who received training. We did not observe differences in participants’ understanding of ACC between groups as measured by the post-test questionnaire. Results are discussed in the context of driver experience and trust in automation.