We present a system, intended for automotive design review use cases, that incorporates a tracked tablet in a CAVE, where both the tablet and the CAVE provide different views and interaction possibilities within the same virtual scene. At its core, this idea is not novel. However, the literature reveals few examples of this paradigm in which virtual information is presented on a second physical device to augment an immersive virtual environment. Similarly, it is unclear where the system should be positioned within existing augmented/mixed/virtual reality taxonomies. We argue that interactions occur within a nesting of virtual and physical contexts, and that formalizing these relationships is important when attempting to understand perceptual issues. The goal of this paper is, thus, to describe the new system by proposing a scheme to formally identify sources of bias and then adapting an existing taxonomy to classify such systems.

This study incorporated a dual-task paradigm, in which participants were asked to perform basic locomotion tasks with one of three interfaces while remembering a sequence of either spatial or verbal items. Interfaces varied in similarity to natural body movements. Stopping performance was compromised when concurrently remembering a spatial, but not verbal, sequence. Also users exhibited lower performance on spatial memory tasks while using more unnatural locomotion interfaces. These results confirm that semi-natural locomotion interfaces require spatial working memory resources and thus locomotion interfaces compete with ongoing spatial tasks, as opposed to those requiring verbal resources or general attention resources.