Swing-In-Place (SIP): A Less Fatigue Walking-in-Place Method With Side-Viewing Functionality for Mobile Virtual Reality

The concept of mobile Virtual Reality (VR) headset that utilize mobile smartphone as the main display and processing device has successfully achieved a low-cost but yet feasible method to implement VR for a mobile user. However, locomotion in mobile VR is still a challenge because the ways to interact with the smartphone are limited. Walking-in-place (WIP) can be used as a hands-free input method to control locomotion inside a mobile VR environment, at the same time, enhance user experience by increasing the sense of immersion. Commonly, WIP implementation in mobile VR uses the inertia sensors of smartphone to detect WIP, thus no additional apparatus is needed. However, common WIP implementation navigates based on user's gaze direction, but in reality, we may walk and look into different direction at the same time. Besides that, fatigue caused by WIP is another important issue to be considered for prolongs usage of VR application. So, we present a less fatigue WIP gesture, swing-in-place (SIP) with a WIP implementation that allows users to travel and look in different directions during locomotion. Our implementation used only the accelerometer and gyroscope in single smartphone. Evaluation results show that SIP able to provide a similar feeling of immersion and it is less fatigue when compared with a common WIP method used in mobile VR. The side-viewing functionality is liked by the users.