Virtual Reality (VR) users typically either sit or stand/walk when using VR; however, the impact of this is little researched, and there is a lack of any broad or systematic analysis of how this difference in physical posture might affect user experience and behavior. To address this gap, we propose such a systematic analysis that was refined through discussions and iterations during a dedicated workshop with VR experts. This analysis was complemented by an online survey to integrate the perspectives of a larger and more diverse group of VR experts, including developers and power users. The result is a validated expert assessment of the impact of posture and degree of embodiment on the most relevant aspects of VR experience and behavior. In particular, we posit potential strong effects of posture on user comfort, safety, self-motion perception, engagement, and accessibility. We further argue that the degree of embodiment can strongly impact cybersickness, locomotion precision, safety, self-motion perception, engagement, technical complexity, and accessibility. We provide a compact visualization of key findings and discuss areas where posture and embodiment do or do not have a known influence, as well as highlight open questions that could guide future research and VR design efforts.

To use the full potential of immersive data analysis when wearing a head-mounted display, users have to be able to navigate through the spatial data. We collected, developed and evaluated 5 different hands-free navigation methods that are usable while seated in the analyst's usual workplace. All methods meet the requirements of being easy to learn and inexpensive to integrate into existing workplaces. We conducted a user study with 23 participants which showed that a body leaning metaphor and an accelerometer pedal metaphor performed best. In the given task the participants had to determine the shortest path between various pairs of vertices in a large 3D graph.

In this work we describe the scenario of fully-immersive desktop VR, which serves the overall goal to seamlessly integrate with existing workflows and workplaces of data analysts and researchers, such that they can benefit from the gain in productivity when immersed in their data-spaces. Furthermore, we provide a literature review showing the status quo of techniques and methods available for realizing this scenario under the raised restrictions. Finally, we propose a concept of an analysis framework and the decisions made and the decisions still to be taken, to outline how the described scenario and the collected methods are feasible in a real use case.

Leaning (the upper body) has several times been shown to be a suitable virtual travel technique when being seated; in both, flying as well as ground-based scenarios. The direction of the steering method most commonly used is gaze/head-directed. However, this does not allow to inspect the environment independently from the direction of movement. The change to torso-directed steering allows for the latter and additionally does not take anything from the natural character of the leaning metaphor. We empirically investigated the impact of this freedom in a ground-based scenario and complemented the conditions with a virtual body-directed method and then crossed all with device-based control conditions. In the conducted study (n = 25), we found the torso-directed methods objectively performed the best (traveled distance, completion time & number of collisions), and found torso-directed leaning subjectively rated the most usable one.

The inquiry into the impact of diverse transitions between cross-reality environments on user experience remains a compelling research endeavor. Existing work often offers fragmented perspectives on various techniques or confines itself to a singular segment of the reality-virtuality spectrum, be it virtual reality or augmented reality. This study embarks on bridging this knowledge gap by systematically assessing the effects of six prevalent transitions while users remain immersed in tasks spanning both virtual and physical domains. In particular, we investigate the effect of different transitions while the user is continuously engaged in a demanding task instead of purely focusing on a given transition. As a preliminary step, we evaluate these six transitions within the realm of pure virtual reality to establish a baseline. Our findings reveal a clear preference among participants for brief and efficient transitions in a task-driven experience, instead of transitions that prioritize interactivity and continuity. Subsequently, we extend our investigation into a cross-reality context, encompassing transitions between virtual and physical environments. Once again, our results underscore the prevailing preference for concise and effective transitions. Furthermore, our research offers intriguing insights about the potential mitigation of visual incoherence between virtual and augmented reality environments by utilizing different transitions.

The ongoing migration of HMDs to the consumer market also allows the integration of immersive environments into analysis workflows that are often bound to an (office) desk. However, a critical factor when considering VR solutions for professional applications is the prevention of cybersickness. In the given scenario the user is usually seated and the surrounding real world environment is very dominant, where the most dominant part is maybe the desk itself. Including this desk in the virtual environment could serve as a resting frame and thus reduce cybersickness next to a lot of further possibilities. In this work, we evaluate the feasibility of a substitution like this in the context of a visual data analysis task involving travel, and measure the impact on cybersickness as well as the general task performance and presence. In the conducted user study ( $n=52$ ), surprisingly, and partially in contradiction to existing work, we found no significant differences for those core measures between the control condition without a virtual table and the condition containing a virtual table. However, the results also support the inclusion of a virtual table in desk-based use cases.