Various viewing and travel techniques are used in immersive virtual reality to allow users to see different areas or perspectives of 3D environments. Our research evaluates techniques for visually showing transitions between two viewpoints in head-tracked virtual reality. We present four experiments that focus on automated viewpoint changes that are controlled by the system rather than by interactive user control. The experiments evaluate three different transition techniques (teleportation, animated interpolation, and pulsed interpolation), different types of visual adjustments for each technique, and different types of viewpoint changes. We evaluated how differences in transition can influence a viewer's comfort, sickness, and ability to maintain spatial awareness of dynamic objects in a virtual scene. For instant teleportations, the experiments found participants could most easily track scene changes with rotational transitions without translational movements. Among the tested techniques, animated interpolations allowed significantly better spatial awareness of moving objects, but the animated technique was also rated worst in terms of sickness, particularly for rotational viewpoint changes. Across techniques, viewpoint transitions involving both translational and rotational changes together were more difficult to track than either individual type of change.

Many researchers have studied methods of effective travel in virtual environments, but little work has considered scene transitions, which may be important for virtual reality experiences like immersive 360 degree movies. In this research, we designed and evaluated three different scene transition techniques in two environments, conducted a pilot study, and collected metrics related to sickness, spatial orientation, and preference. Our preliminary results indicate that faster techniques are generally preferred by gamers and more gradual transitions are preferred by participants with less experience with 3D gaming and virtual reality.

Traditionally in virtual reality systems, head tracking is used in head-mounted displays (HMDs) to allow users to control viewing using 360-degree head and body rotations. Our research explores interaction considerations that enable semi-natural methods of view control that will work for seated use of virtual reality with HMDs when physically turning all the way around is not ideal, such as when sitting on a couch or at a desk. We investigate the use of amplified head rotations so physically turning in a comfortable range can allow viewing of a 360-degree virtual range. Additionally, to avoid situations where the user's neck is turned in an uncomfortable position for an extended period, we also use redirection during virtual movement to gradually realign the user's head position back to the neutral, straight-ahead position. We ran a controlled experiment to evaluate guided head rotation and amplified head rotation without realignment during movement, and we compared both to traditional one-to-one head-tracked viewing as a baseline for reference. After a navigation task, overall errors on spatial orientation tasks were relatively low with all techniques, but orientation effects, sickness, and preferences varied depending on participants' 3D gaming habits. Using the guided rotation technique, participants who played 3D games performed better, reported higher preference scores, and demonstrated significantly lower sickness results compared to non-gamers.