Keep Calm and Ride Along: Passenger Comfort and Anxiety as Physiological Responses to Autonomous Driving Styles

Autonomous vehicles have been rapidly progressing towards full autonomy using fixed driving styles, which may differ from individual passenger preferences. Violating these preferences may lead to passenger discomfort or anxiety. We studied passenger responses to different driving style parameters in a physical autonomous vehicle. We collected galvanic skin response, heart rate, and eye-movement patterns from 20 participants, along with self-reported comfort and anxiety scores. Our results show that the presence and proximity of a lead vehicle not only raised the level of all measured physiological responses, but also exaggerated the existing effect of the longitudinal acceleration and jerk parameters. Skin response was also found to be a significant predictor of passenger comfort and anxiety. By using multiple independent events to isolate different driving style parameters, we demonstrate a method to control and analyze such parameters in future studies.