Being in Two Spaces: Investigating and Mitigating Spatial Conflicts in Virtual Reality

Virtual Reality (VR) allows people to immerse themselves in a computer-mediated environment. When interacting in VR, a person mainly sees the virtual environment and is visually disconnected from the physical space. However, this person is still physically interacting within the physical space—the experience of using VR occurs in two spaces. Simultaneously interacting with both the virtual and the physical space can lead to accidents, such as colliding with obstacles, like furniture or bystanders. Especially since VR technology has become more prominent in diverse physical spaces, such as during transportation, at home, or outdoors, the chance of accidents and collisions increases, negatively affecting the VR experience. I refer to this phenomenon as a spatial conflict caused by a misalignment between two spaces, disrupting the VR experience. To enhance the safety of VR interaction, more knowledge is needed to identify different types of spatial conflicts, understand how they form in the VR experience, and develop mitigation guidelines. I define two categories of spatial conflicts: (1) cognitive spatial conflicts which may occur in the cognitive process when a person updates spatial or body representations, and (2) action spatial conflicts which are caused by the actions of people while using VR. First, I conducted one lab study, demonstrating that cognitive spatial conflicts can occur when updating spatial representations and affect the sense of presence. Through one lab and two online studies, I showed that when experiencing a virtual body, cognitive spatial conflicts can negatively affect the judgment of body ownership. For action spatial conflicts, I investigated collisions with the physical space by identifying behaviors and reasons for how people interact with the VR safety boundary through an online survey and lab study. Further, I developed an interaction technique (FingerMapper) to reduce collisions while using VR in a confined physical space. Through a speculative design process, I explored how action spatial conflicts may occur in future VR scenarios and derived mitigation guidelines. Based on my findings, I discuss alternative types of conflicts, how to enhance VR safety, and implications for the definition of presence. Finally, I identify two major challenges for future research: mitigating spatial conflicts in collaborative VR scenarios and developing computational models to further understand cognitive strategies when people interact in two spaces. This thesis contributes a better understanding of spatial conflicts in VR and their mitigation, consisting of (1) empirical evidence for cognitive spatial conflicts during spatial updating and the formation of body-ownership judgments, (2) empirical evidence for action spatial conflicts by identifying behaviors and strategies of how people interact with the VR safety boundary and obstacles, and (3) mitigation guidelines and an interaction technique (FingerMapper) for action spatial conflicts.