Stereoscopic bimanual interaction for 3D visualization

Virtual Environments (VE) are being widely used in various research fields for several decades such as 3D visualization, education, training and games. VEs have the potential to enhance the visualization and act as a general medium for human-computer interaction (HCI). However, limited research has evaluated virtual reality (VR) display technologies, monocular and binocular depth cues, for human depth perception of volumetric (non-polygonal) datasets. In addition, a lack of standardization of three-dimensional (3D) user interfaces (UI) makes it challenging to interact with many VE systems. To address these issues, this dissertation focuses on evaluation of effects of stereoscopic and head-coupled displays on depth judgment of volumetric dataset. It also focuses on evaluation of a two-handed view manipulation techniques which support simultaneous 7 degree-of-freedom (DOF) navigation (x,y,z + yaw,pitch,roll + scale) in a multi-scale virtual environment (MSVE). Furthermore, this dissertation evaluates auto-adjustment of stereo view parameters techniques for stereoscopic fusion problems in a MSVE. Next, this dissertation presents a bimanual, hybrid user interface which combines traditional tracking devices with computer-vision based "natural" 3D inputs for multi-dimensional visualization in a semi-immersive desktop VR system. In conclusion, this dissertation provides a guideline for research design for evaluating UI and interaction techniques

Development and quasi-experimental evaluation of a screen-based virtual reality tutorial

The challenges users face when interacting with screen-based virtual reality (VR) are addressed in this study with theories from the literature to open a line of inquiry into pre-immersion training development as described by Ausburn and Ausburn (2010). Cognitive load (Sweller, 1988) and wayfinding (Lynch, 1960) are discussed as potential theories underlying the challenges new virtual reality users face, and a tutorial is designed employing the theories of advance organizers (Ausbel, 1960), discovery learning (Bruner, 1961), and chunking (Miller, 1956; Anderson, 1977) alongside Gagne's (1965) nine events of instruction to supplant (Ausburn & Ausburn, 2003; Solomon, 1970) those challenges. The researcher-developed tutorial is quasi-experimentally evaluated and qualitatively assessed by the study participants to inform the development of an introductory checklist for designing VR training tutorials. The researcher found that the experimental tutorial helped participants navigate within virtual reality environments, promoted the transfer of training with curricular materials, helped users develop a sense of presence in the virtual environment, and supported a reduction of the subjects' perceived cognitive load. However, expected gender differences were not evident in the data, and while users' perceived cognitive load was reduced by using the tutorial, there was no significant effect on their learning performance, suggesting that other factors may influence performance in virtual environments. Also, instructional design flaws of the screen-based tutorial were discussed, and the VR tutorial design checklist was outlined