Drivers' overall comfort experiences of reclined positions in a passenger car with an automated driving function

-Automated driving (AD) in cars enables reclined positions when drivers disengage from driving tasks. The objective was to explore driver comfort in self-selected reclined positions during AD, and whether the chosen seat back angle is affected by stature. The study involved 29 participants in upright and reclined positions during AD on a test track at 30 km/h. After experiencing AD, the participants could adjust their reclined position settings. Seat settings of upright, reclined and adjusted reclined positions were collected, along with questionnaire and interview data about comfort. Statistical tests and thematic analysis were performed. The results implied that drivers may prefer reclined positions during AD, if they can observe the traffic and intervene with the AD system. Regardless of stature, drivers using AD do not want to recline as much as expected from static experiments. The automotive industry should revisit expectations for reclined positions to ensure driver comfort in AD.