Walking-in-Place for VR Navigation Independent of Gaze Direction Using a Waist-Worn Inertial Measurement Unit

Many techniques have been proposed for navigation using head-mounted-displays (HMDs) in virtual reality (VR). A walking-in-place (WIP) interface for virtual locomotion provides a high presence and an immersive experience in a virtual environment (VE). However, most of the WIP techniques can only navigate users in the direction of their gaze. Other WIP methods considering virtual locomotion direction have complex configurations or are only feasible when the tracking spaces are not limited. This paper proposes a WIP interface independent of gaze direction based on the data analysis of waist-mounted inertial sensors. Our method can navigate in the locomotion direction by calculating the orientation of the pelvis. We experimentally compared two WIP methods using a navigation task that required participants to periodically observe the surrounding VE: (1) Conventional WIP (gaze-based direction) (2) Proposed WIP (pelvis-based direction). While there was no difference in learnability or cybersickness between the two methods, the proposed method had shorter task time and higher efficiency.