Understanding Perspectives for Single- and Multi-Limb Movement Guidance in Virtual 3D Environments

Movement guidance in virtual reality has many applications ranging from physical therapy, assistive systems to sport learning. These movements range from simple single-limb to complex multi-limb movements. While VR supports many perspectives – e.g., first person and third person – it remains unclear how accurate these perspectives communicate different movements. In a user study (N=18), we investigated the influence of perspective, feedback, and movement properties on the accuracy of movement guidance. Participants had on average an angle error of 6.2° for single arm movements, 7.4° for synchronous two arm movements, and 10.3° for synchronous two arm and leg movements. Furthermore, the results show that the two variants of third-person perspectives outperform a first-person perspective for movement guidance (19.9% and 24.3% reduction in angle errors). Qualitative feedback confirms the quantitative data and shows users have a clear preference for third-person perspectives. Through our findings we provide guidance for designers and developers of future VR movement guidance systems.