To Use or Not to Use Viewpoint Oscillations When Walking in VR? State of the Art and Perspectives.

Viewpoint oscillations are periodic changes in the position and/or orientation of the point of view in a virtual environment. They can be implemented in Virtual Reality (VR) walking simulations to make them feel closer to real walking. This is especially useful in simulations where users remain in place because of space or hardware constraints. As for today, it remains unclear what exact benefit they bring to user experience during walking simulations, and with what characteristics they should be implemented. To answer these questions, we conduct a systematic literature review focusing on five main dimensions of user experience (walking sensation, vection, cybersickness, presence and embodiment) and discuss 44 articles from the fields of VR, Vision, and Human-Computer Interaction. Overall, the literature suggests that viewpoint oscillations benefit vection, and with less evidence, walking sensation and presence. As for cybersickness, the literature contains contrasted results. Based on these results, we recommend using viewpoint oscillations in applications that require accurate distance or speed perception, or that aim to provide compelling walking simulations without a walking avatar, and a particular attention should be paid to cybersickness. Taken together, this work gives recommendations for enhancing walking simulations in VR, which may be applied to entertainment, virtual visits, and medical rehabilitation.