Evaluation of users' experience and posture in a rotated swivel seating configuration.

This study aims to evaluate a car passenger's experience and actions in a rotated seat in terms of interaction with an adjacent passenger. A static user study was conducted, using a stationary test vehicle with two front row seats facing rearwards. The seats were mounted on a swivel plate which allowed inboard rotation. Thirty-two participants in 16 test pairs were grouped based on stature; short or tall. The participants within each pair knew each other. Three seating configurations were evaluated; 0° and 10° and 20° inboard rotated position of both seats. The participants were seated in each seating configuration for 10 min; 5 min they engaged in a conversation with each other and 5 min they were watching media on an Ipad mounted in front of them. Subjective data from each participant on their experiences and preferences were collected through questionnaires, and objective data on sitting postures and eye gaze were collected through video recording. Ninety-two percent of the short participants preferred to sit in the 20° rotated seating configuration when watching media and 75% preferred the 20° seating configuration when engaged in conversation. Compared to short participants, the tall participants showed a relative larger spread in seating configuration preference; 15% and 30% of them preferred the reference position for media and conversation, respectively. Leg interference was common for tall participants when 20° inboard rotated. They perceived it uncomfortable and used various strategies to avoid contact, including crossing legs or feet. Time spent with mutual eye contact did not vary by seating configuration. This static user study shows that rotated seats could be a desired seating configuration in future autonomous vehicles for individuals who know each other. It reveals the reasons behind the preferences and the extent of desired seat rotation, showing differences between tall and short individuals. By understanding how occupant position and posture can be influenced by offering various seating configurations, the occupant can choose a comfortable position that is also safe. The leg and feet positions are raised as the body region with most variations and for which an increased understanding of influence in a crash is encouraged.