| Many practical applications of Virtual Reality (VR) technology rely on adequate immersive representations of 3D spaces and support of embodied, dynamic interactions with the virtual world. Evaluation of these properties remains an important research problem.;This thesis aims at developing a method of conducting user evaluations of dynamic, full-body interactions in VR systems based on using support for perception and action coupling as a criterion for comparison. The thesis has three main components.;First, the thesis starts by presenting an experimental perceptual evaluation study looking at distance perception in real and virtual environments. The results indicate that the choice of the method to report perceived distances (i.e. the type of action used to express perceptual variable of interest) may have a significant effect on the outcome of the study. We argue for the need to develop an approach to VR evaluation that holistically considers both perception and action.;Second, we propose a theoretical framework to conduct such user evaluations based on the notion of affordances. The thesis presents the second experimental study that explores perception of affordances in a complex, realistic task of bicycling across two lanes of opposing traffic in a VR simulator. This experiments highlights methodological approach to studies of user's perception of dynamic affordances.;Finally, we present an experimental study that builds on theoretical and methodological frameworks developed in the thesis to explore the effects of display type and locomotion modality on user performance in a dynamic VR task that involves synchronization of self-motion with motion of virtual objects. The results inform our understanding of the trade-offs involved in selecting major components of the VR system. |
