Functional differences in gaze based on roles in collision avoidance between wheelchair-type personal mobility vehicles

Recently, the development of personal mobility vehicles (PMVs) has expanded shared spaces where pedestrians and different forms of mobility interact. In these shared spaces, traffic participants must interact with PMVs using strategies different from those used when interacting with pedestrians. This study aimed to elucidate the role-based differences in the function of gaze toward the partner in collision avoidance between PMVs. The experiment measured gaze, positional information, and understanding of the partner's intentions as two wheelchair-type PMVs passed each other and avoided collision. The results showed that the function of gaze varies based on roles in collision avoidance. First, we observed that the leader, who passes through the collision point first, gazes toward their partner to demand coordination behavior, while the follower, who passes through the collision point later, gazes at their partner to prompt coordination behavior and adjust their own behavior. Second, our results showed that only the follower's gaze improves the ratings of understanding and conveying the partner's intentions. These findings provide evidence that gaze is a critical source of information in collision avoidance between two PMVs, and its utilization varies depending on the role.