What is Center of Mass (COM)

Users sometimes lost their balance or even fell down when they played virtual reality (VR) games or projects. This may be attributed to degree of content, high-rate of latency, coordination of various sensory inputs, and others. The authors investigated the effect of sudden visual perturbations on human balance in VR environment. This research used the latest VR head mounted display to present visual perturbations to disturb balance. To quantify balance, measured by double-support and single-support stance, the authors measured the subject's center of pressure (COP) using a force plate. The results indicated that visual perturbations presented in virtual reality disrupted balance control in the single support condition but not in the double support condition. Results from this study can be applied to clinical research on balance and VR environment design.