Drivers’ hand positions on the steering wheel while using Adaptive Cruise Control (ACC) and driving without the system

Adaptive Cruise Control (ACC) is an Advanced Driver Assistance System that maintains a predefined speed and headway to the vehicle in front. Despite the expected benefits, the effects of ACC usage on drivers’ behaviour are not completely identified yet. In this context, the present study was performed to investigate drivers’ perceived risk and mental workload associated with the usage of ACC, through the measurement of drivers’ hand positions (high, medium, and low) on the steering wheel. In addition, the study also aimed to understand the effect of sensation seeking on the drivers’ hand position. A study was conducted in a driving simulator, with 26 participants who drove twice, once with ACC and once manually, along the same route. Using Wilcoxon exact test, the results showed that the percentage of high and low hand position on the steering wheel did not change while driving with ACC or manually. Besides, no differences were found between the ACC driving condition and the manual driving condition on self-reported experienced mental workload and perceived risk. However, the score on the sensation seeking questionnaire was related to the hand positions selected by the participants.