Virtual reality sickness typically results from visual-vestibular conflict. Because self-motion from optical flow is driven most strongly by motion at the periphery of the retina, reducing the user’s field-of-view (FOV) during locomotion has proven to be an effective strategy to minimize visual vestibular conflict and VR sickness. Current FOV restrictor implementations reduce the user’s FOV by rendering a restrictor whose center is fixed at the center of the head mounted display (HMD), which is effective when the user’s eye gaze is aligned with head gaze. However, during eccentric eye gaze, users may look at the FOV restrictor itself, exposing them to peripheral optical flow which could lead to increased VR sickness. To address these limitations, we develop a foveated FOV restrictor and we explore the effect of dynamically moving the center of the FOV restrictor according to the user’s eye gaze position. We conducted a user study (n=22) where each participant uses a foveated FOV restrictor and a head-fixed FOV restrictor while navigating a virtual environment. We found no statistically significant difference in VR sickness measures or noticeability between both restrictors. However, there was a significant difference in eye gaze behavior, as measured by eye gaze dispersion, with the foveated FOV restrictor allowing participants to have a wider visual scan area compared to the head-fixed FOV restrictor, which confined their eye gaze to the center of the FOV.
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VR Sickness Adaptation With Ramped Optic Flow Transfers From Abstract To Realistic Environments
VR sickness is a major concern for many users as VR continues its expansion towards widespread everyday use. VR sickness is thought to arise, at least in part, due to the user’s intolerance of conflict between the visually simulated self-motion and actual physical movement. Many mitigation strategies involve consistently modifying the visual stimulus to reduce its impact on the user, but this individualized approach can have drawbacks in terms of complexity of implementation and non-uniformity of user experience. This study presents a novel alternative approach that involves training the user to better tolerate the adverse stimulus by tapping into natural adaptive perceptual mechanisms. In this study, we recruited users with limited VR experience that reported susceptibility to VR sickness. Baseline sickness was measured as participants navigated a rich and naturalistic visual environment. Then, on successive days, participants were exposed to optic flow in a more abstract visual environment, and strength of the optic flow was successively increased by increasing the visual contrast of the scene, because strength of optic flow and the resulting vection are thought to be major causes of VR sickness. Sickness measures decreased on successive days, indicating that adaptation was successful. On the final day, participants were again exposed to the rich and naturalistic visual environment, and the adaptation was maintained, demonstrating that it is possible for adaptation to transfer from more abstract to richer and more naturalistic environments. These results demonstrate that gradual adaptation to increasing optic flow strength in well-controlled, abstract environments allows users to gradually reduce their susceptibility to sickness, thereby increasing VR accessibility for those prone to sickness.
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- Award ID(s):
- 1911041
- NSF-PAR ID:
- 10355651
- Date Published:
- Journal Name:
- Frontiers in Virtual Reality
- Volume:
- 3
- ISSN:
- 2673-4192
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.3389/frvir.2022.848001
