Mutual collision avoidance during walking in real and collaborative virtual environments

In walkable multi-user HMD-based VR immersed users have to avoid colliding with each other while performing tasks or exploring the virtual environment. This paper presents an experiment in which we compare mutual collision avoidance behaviour of pairs of users walking in the matched real and virtual environments. To generalize our study, we investigate two types of multi-user VR setup: one in which both users share a common tracking space (colocated condition) and one where they move in two separate tracking spaces while sharing a common virtual space (distributed condition). Our results indicated significant differences in locomotor trajectories of participants between the real and virtual conditions. Precisely, we observed an increase in the clearance distance and the median path curvature and a decrease in the walking speed when participants performed the test in VR in the colocated condition. Moreover, we found effects of pre-conditioning between the colocated and distributed scenarios.