Influence of seating orientation on motion sickness in autonomous vehicles

A major advantage of autonomous vehicles (AVs) is the passengers' ability to perform non-driving related tasks (NDRTs) while being driven. Among these NDRTs, social interaction with other passengers is considered to be particularly valuable. Seating layouts featuring rotatable front seats will enable a new level of social interaction during autonomous car journeys. However, being seated against the direction of travel is not very popular. Fear of motion sickness is one of the main reasons for this reluctance, which is commonly explained by the inability to see the road ahead. This raises the question to what extent motion sickness in rearward facing passengers of autonomous vehicles is to be expected and to what degree this is caused by the inability to see through the windscreen. To answer this question, a field experiment in real traffic with N = 55 participants was conducted. Seating orientation and forward view were manipulated and their effects on motion sickness as well as related factors relevant to the acceptance of AVs were analyzed. Both a rearward seating orientation and a restricted forward view led to significantly increased motion sickness. The insights gained serve as a basis for the development of HMIs that improve the acceptance of rearward facing seating orientations in AVs.