The influence of the viewpoint in a self-avatar on body part and self-localization

The goal of this study is to determine how a self-avatar in virtual reality, experienced from different viewpoints on the body (at eye- or chest-height), might influence body part localization, as well as self-localization within the body. Previous literature shows that people do not locate themselves in only one location, but rather primarily in the face and the upper torso. Therefore, we aimed to determine if manipulating the viewpoint to either the height of the eyes or to the height of the chest would influence self-location estimates towards these commonly identified locations of self. In a virtual reality (VR) headset, participants were asked to point at sev- eral of their body parts (body part localization) as well as "directly at you" (self-localization) with a virtual pointer. Both pointing tasks were performed before and after a self-avatar adaptation phase where participants explored a co-located, scaled, gender-matched, and animated self-avatar. We hypothesized that experiencing a self-avatar might reduce inaccuracies in body part localization, and that viewpoint would influence pointing responses for both body part and self-localization. Participants overall pointed relatively accurately to some of their body parts (shoulders, chin, and eyes), but very inaccurately to others, with large undershooting for the hips, knees, and feet, and large overshooting for the top of the head. Self-localization was spread across the body (as well as above the head) with the following distribution: the upper face (25%), the up- per torso (25%), above the head (15%) and below the torso (12%). We only found an influence of viewpoint (eye- vs chest-height) during the self-avatar adaptation phase for body part localization and not for self-localization. The overall change in error distance for body part localization for the viewpoint at eye-height was small (M = –2.8 cm), while the overall change in error distance for the viewpoint at chest-height was significantly larger, and in the upwards direction relative to the body parts (M = 21.1 cm). In a post-questionnaire, there was no significant difference in embodiment scores between the viewpoint conditions. Most interestingly, having a self-avatar did not change the results on the self-localization pointing task, even with a novel viewpoint (chest-height). Possibly, body-based cues, or memory, ground the self when in VR. However, the present results caution the use of altered viewpoints in applications where veridical position sense of body parts is required

The effectiveness of training in virtual environments

The research presented in this thesis explores the use of consumer virtual reality technology for training, comparing its validity to more traditional training formats. The need to evaluate the effectiveness of training in virtual environments is critical as a wider audience gains access to an array of emerging virtual reality consumer devices. Training is an obvious use case for these devices. This is motivated by the well-known success of domain-specific training simulators, the ability to train in safe, controlled environments and the potential to launch training programs when the physical components required to complete a task are not readily available. In this thesis, we present four user studies that aim to compare the effectiveness of systems with varying levels of immersion for learning transfer of several tasks, ranging from object location spatial memory to more complex assembly procedures. For every study, evaluation of the effectiveness of training took place in a real-world, physical environment. The first two studies compare geometric and self-motion models in describing human spatial memory through scale distortions of real and virtual environments. The third study examines the effect of level of immersion, self-avatar and environmental fidelity on object location memory in real and virtual environments. The fourth study compares the effectiveness of physical training and virtual training for teaching a bimanual assembly task. Results highlight the validity of virtual environments for training. The overall conclusion is that virtual training can yield a resulting performance that is superior to other, more traditional training formats. Combined, the outcomes of each of the user studies motivate further study of consumer virtual reality systems in training and suggest considerations for the design of such virtual environments