Cybersickness continues to bar many individuals from taking full advantage of virtual reality (VR) technology. Previous work has established that navigating virtual terrain with elevation changes poses a significant risk in this regard. In this paper, we investigate the effectiveness of three cybersickness reduction strategies on users performing a navigation task across virtual elevation-altering terrain. These strategies include static field of view (FOV) reduction, a flat surface approach that disables terrain collision and maintains constant elevation for users, and SmoothRide, a novel technique designed to dampen a user's perception of vertical motion as they travel. To assess the impact of these strategies, we conducted a within-subjects study involving 61 participants. Each strategy was compared against a control condition, where users navigated across terrain without any cybersickness reduction measures in place. Cybersickness data were collected using the Fast Motion Sickness Scale (FMS) and Simulator Sickness Questionnaire (SSQ), along with galvanic skin response (GSR) data. We measured user presence using the IGroup Presence questionnaire (IPQ) and a Single-Item Presence Scale (SIP). Our findings reveal that users experienced significantly lower levels of cybersickness using SmoothRide or FOV reduction. Presence scores reported on the IPQ were statistically similar between SmoothRide and the control condition. Conversely, terrain flattening had adverse effects on user presence scores, and we could not identify a significant effect on cybersickness compared to the control. We demonstrate that SmoothRide is an effective, lightweight, configurable, and easy-to-integrate tool for reducing cybersickness in simulations featuring elevation-altering terrain.

Virtual reality (VR) technologies are used in a diverse range of applications. Many of these involve an embodied conversational agent (ECA), a virtual human who exchanges information with the user. Unfortunately, VR technologies remain inaccessible to many users due to the phenomenon of cybersickness: a collection of negative symptoms such as nausea and headache that can appear when immersed in a simulation. Many factors are believed to affect a user's level of cybersickness, but little is known regarding how these factors may influence a user's opinion of an ECA. In this study, we examined the effects of virtual stairs, a factor associated with increased levels of cybersickness. We recruited 39 participants to complete a simulated airport experience. This involved a simple navigation task followed by a brief conversation with a virtual airport customs agent in Spanish. Participants completed the experience twice, once walking across flat hallways, and once traversing a series of staircases. We collected self-reported ratings of cybersickness, presence, and perception of the ECA. We additionally collected physiological data on heart rate and galvanic skin response. Results indicate that the virtual staircases increased user level's of cybersickness and reduced their perceived realism of the ECA, but increased levels of presence.

Cybersickness (i.e., visually induced motion sickness) serves as a significant obstacle to the usage and broader adoption of virtual reality (VR) technologies. This collection of symptoms akin to motion sickness can be impacted by different characteristics of a virtual experience, such as visual realism and optical flow. However, relatively little is known regarding how cybersickness is influenced by traversing uneven virtual terrain. In this study, we aim to better understand the impacts of different virtual terrain types on cybersickness in VR. We recruited 38 participants to navigate a virtual forest environment with three terrain variants: flat surface, terrain with regular bumps, and irregular terrain generated from Perlin noise. We collected cybersickness data using the Fast Motion Sickness Scale (FMSS) and Simulator Sickness Questionnaire (SSQ) in addition to galvanic skin response data. Our results indicate that users felt greater levels of cybersickness in the presence of regular bumps and irregular terrain than they did when traversing flat geometry. We recommend that designers exercise caution when incorporating uneven terrain into their virtual experiences, and maintain awareness of the risks carried by these design decisions.