Design and Evaluation of 3D Multimodal Virtual Environments for Visually Impaired People

Spatial information presented visually is not easily accessible to visually impaired users. Current technologies, such as screen readers, cannot intuitively convey spatial layout or structure. This lack of overview is an obstacle for a visually impaired user, both when using the computer individually and when collaborating with other users. With the development of haptic and audio technologies, it is possible to let visually impaired users access to threedimensional (3D) Virtual Reality (VR) environments through the senses of touch and hearing. The work presented in this thesis comprises investigations of haptic and audio interaction for visually impaired computer users in two stages. The first stage of my research focused on collaborations between sighted and blind-folded computer users in a shared virtual environment. One aspect I considered is how different modalities affect one’s awareness of the other’s actions, as well as of one’s own actions, during the work process. The second aspect I investigated is common ground, i.e. how visually impaired people obtain a common understanding of the elements of their workspace through different modalities. A third aspect I looked at was how different modalities affect perceived social presence, i.e. their ability to perceive the other person’s intentions and emotions. Finally, I attempted to understand how human behavior and efficiency in task performance are affected when different modalities are used in collaborative situations. The second stage of my research focused on how the visually impaired access 3D multimodal virtual environment individually. I conducted two studies based on two different haptic and audio prototypes concerning understanding the effect of haptic-audio modalities on navigation and interface design. One prototype that I created was a haptic and audio game, a