Reduction of kinetosis via motion cues in automated vehicles

Abstract

Background: Passengers are more likely to experience kinetosis also known as “motion sickness” in automated vehicles than in manually driven ones. Therefore, the reduction or avoidance of motion sickness will become an increasingly important psychological issue to be dealt with. In several studies the provision of motion cues via light-based in-car Human-Machine Interfaces (HMI) has emerged as a promising method to alleviate kinetosis. However, questions of design and user experience of these HMI solutions are still open. Method: In this experimental simulation study with repeated measurements we assessed the design and user experience of light-based HMI designs. Participants experienced a virtual drive in an automated vehicle in an urban scenario, both with and without the HMI providing information about the vehicle’s directional changes. In order to preclude potential carryover effects, the two conditions were tested on separate days in a balanced order. The degree of experienced kinetosis and user experience ratings were assessed. In addition, the participants head motion during the drive was tracked via a head-mounted VR device as the movement of the head has been shown to correlate with subjective motion sickness. Scores for yaw, pitch and roll during turns and the straight sections in-between were calculated. Results: Contrary to our hypothesis, participants did not experience generally less kinetosis in the motion cue condition with the HMI. However, there was a significantly pronounced habituation effect for participants who were exposed to the non-motion cue condition first and the motion cue condition second in comparison to participants who were exposed to these two conditions in the opposite order. We could also observe differences in the participants’ head motions between the two conditions. Additionally, the HMI system’s design received favourable user experience ratings from participants regardless of condition order. Conclusion: We will discuss implications of these promising positive results for subsequent studies involving physical vehicles and for the design and specifications of light-based motion cue systems that aim to alleviate kinetosis.