Interface metaphors are thought to enable an intuitive and effective interaction with a user interface by allowing users to draw on existing knowledge and reducing the need for instructions. This makes metaphors a promising candidate to drive the development of locomotion interfaces for virtual reality (VR). Since creating metaphoric interfaces can be difficult, it is important to analyze how typical locomotion metaphors can support an intuitive interaction. We performed a qualitative online study to observe the effect of typical metaphors (Walking, Steering, Flying, and Teleportation) and the influence of perceived affordances and user background. Our analysis shows that users adapt the interface expectations induced by metaphors to fit the perceived affordances instead of changing them. Several interests, the age, education, and gender influenced the expectations regarding the VR locomotion interface. Our findings contribute to a better understanding of users' mental models of VR locomotion metaphors, which seem necessary for designing more intuitive locomotion.

Overlaying real-world objects with virtual information is a fundamental aspect of augmented reality (AR). Traditional techniques typically rely on marker-based or feature-based computer vision methods, each with inherent limitations regarding robustness and environmental adaptability. In this paper, we introduce the Three-Touch (TT) technique, a novel approach that enables users to manually align virtual content with physical objects by selecting corresponding feature pairs. We conduct a comparative study between the TT technique and a conventional grab gesture (G) method, evaluating usability, user experience, task load, positioning accuracy, and task completion time. Our findings indicate that while the TT technique reduces physical and mental effort, it may lead to greater positional offsets and reduced task performance compared to the G technique.

The change of the user's viewpoint in an immersive virtual environment, called locomotion, is one of the key components in a virtual reality interface. Effects of locomotion, such as simulator sickness or disorientation, depend on the specific design of the locomotion method and can influence the task performance as well as the overall acceptance of the virtual reality system. Thus, it is important that a locomotion method achieves the intended effects. The complexity of this task has increased with the growing number of locomotion methods and design choices in recent years. Locomotion taxonomies are classification schemes that group multiple locomotion methods and can aid in the design and selection of locomotion methods. Like locomotion methods themselves, there exist multiple locomotion taxonomies, each with a different focus and, consequently, a different possible outcome. However, there is little research that focuses on locomotion taxonomies. We performed a systematic literature review to provide an overview of possible locomotion taxonomies and analysis of possible decision criteria such as impact, common elements, and use cases for locomotion taxonomies. We aim to support future research on the design, choice, and evaluation of locomotion taxonomies and thereby support future research on virtual reality locomotion.

Despite advances regarding autonomous functionality for robots, teleoperation remains a means for performing delicate tasks in safety critical contexts like explosive ordnance disposal (EOD) and ambiguous environments. Immersive stereoscopic displays have been proposed and developed in this regard, but bring about their own specific problems, e.g., simulator sickness. This work builds upon standardized test environments to yield reproducible comparisons between different robotic platforms. The focus was placed on testing three optronic systems of differing degrees of immersion: (1) A laptop display showing multiple monoscopic camera views, (2) an off-the-shelf virtual reality headset coupled with a pantilt-based stereoscopic camera, and (3) a so-called Telepresence Unit, providing fast pan, tilt, yaw rotation, stereoscopic view, and spatial audio. Stereoscopic systems yielded significant faster task completion only for the maneuvering task. As expected, they also induced Simulator Sickness among other results. However, the amount of Simulator Sickness varied between both stereoscopic systems. Collected data suggests that a higher degree of immersion combined with careful system design can reduce the to-be-expected increase of Simulator Sickness compared to the monoscopic camera baseline while making the interface subjectively more effective for certain tasks.