CaliView: Continuous Viewpoint Calibration Using Dynamic Rotation Gain Control

Head tracking allows users of Virtual Reality (VR) to freely rotate their heads 360 degrees while exploring virtual environments. When using VR in a limited space, the ability to physically rotate one's head is limited to a specific range. To address this issue, previous studies have proposed methods to employ distinct rotation factors for real and imaginary rotations. However, its primary usage lies in redirected walking; thus, it is unsuitable for seated VR. In this article, we propose CaliView, which consistently adjusts the user's perspective to always face an optimal direction in VR, all while ensuring a comfortable posture. CaliView continuously controls the rotation gain to ensure that the disparity between the present body orientation and the optimal orientation is reduced to zero, encouraging the user to assume a forward-facing position with the target orientation. To assess the suggested approach, CaliView, we experimented to compare three conditions: CaliView, snap turning only (SnapTurn), and hybrid of CaliView and snap turning (Hybrid). The research findings suggest that CaliView functions as a useful reorientation technique, enabling implicit reorientation without sacrificing the user experience. Additionally, this study showcases its compatibility with various other techniques, such as the traditional snap-turn, thus emphasizing its versatility.