Graduation Year


Document Type




Degree Name

Doctor of Philosophy (Ph.D.)

Degree Granting Department

Computer Science and Engineering

Major Professor

Srinivas Katkoori, Ph.D.

Co-Major Professor

Andrew Raij, Ph.D.

Committee Member

Rajiv Dubey, Ph.D.

Committee Member

Paul Rosen, Ph.D.

Committee Member

Sriram Chellappan, Ph.D.

Committee Member

Eleazar Vasquez, Ph.D.


Redirected Walking, Point and Teleport, Controllers, Walk in Place, Head Mounted Display


In the recent years, virtual reality has been used as an effective tool for a wide range of areas such as training, rehabilitation, education and games. The affordability of the new generation headsets helped this medium to become more widespread. However, in order for virtual reality to become mainstream, more content that is specifically designed for this medium is needed. Since virtual reality is a different technology than the computer systems, different design principles may be required for these content for better user experience. One of the crucial components of virtual reality applications is locomotion, since the viewpoint of the user is very important in immersing the users into virtual reality and locomotion is used for moving the viewpoint of user in virtual environments. Locomotion in virtual reality is expected to have a direct effect on user experience in terms of many elements such as effort, enjoyment, frustration, motion sickness and presence. Up to date, many locomotion techniques for virtual reality have been studied in the literature. However, many of these techniques were evaluated in large tracked areas. Although professional motion tracking systems can track large areas, today’s new generation affordable commercial virtual reality systems can only track room scale environments. This dissertation aims at evaluating different locomotion techniques in room scale tracked areas for neurotypical individuals and individuals with ASD. Several previous studies concurred that virtual reality is an effective medium for the training and rehabilitation of individuals with ASD. However, no previous study evaluated locomotion in virtual reality for this specific population. Thus, this dissertation aims at finding out the suitable virtual reality locomotion techniques for individuals with ASD.

With these motivations, in this dissertation, locomotion techniques for room scale virtual reality were evaluated under three experiments: virtual reality for vocational rehabilitation system, evaluation of eight virtual reality locomotion techniques, and point & teleport direction specification experiment.

In the first experiment of virtual reality for vocational rehabilitation system, locomotion, interaction, and display components in an immersive virtual reality system for vocational rehabilitation was evaluated by 10 neurotypical individuals and 9 individuals with high functioning ASD. The results indicated that neurotypical individuals favored real walking over walk-in-place; tangible interaction over haptic device, touch & snap and touch screen; and head mounted display over curtain screen. For the participants with high functioning ASD, real walking was favored over walk-in-place; touch screen was favored over haptic device, tangible interaction and touch & snap; and curtain screen was favored over head mounted display.

In the second experiment, eight virtual reality locomotion techniques were evaluated in a room scale tracked area (2m by 2m). These eight locomotion techniques were: redirected walking, walk-in-place, stepper machine, point & teleport, joystick, trackball, hand flapping and flying. Among these locomotion techniques, the three were commonly used in virtual reality (redirected walking, walk-in-place and joystick), the two were unexplored –explored previously only by a few related studies (stepper machine and point & teleport), and the three were selected and/or modified for individuals with ASD based on their common characteristics (trackball, hand flapping and flying). These eight techniques were evaluated in an immersive virtual reality test environment. A user study was performed with 16 neurotypical participants and 15 participants with high functioning ASD. The results indicated that for neurotypical individuals, point & teleport, joystick and redirected walking were suitable virtual reality locomotion techniques for room scale tracked areas whereas hand flapping and flying were not suitable. For individuals with high functioning ASD, point & teleport, joystick and walk-in-place were suitable virtual reality locomotion techniques for room scale tracked areas whereas hand flapping and flying were not suitable.

Locomotion techniques that are similar to point & teleport have been starting to be used in commercial video games, however were not evaluated in the literature. For this reason, a separate experiment was performed as the third experiment to investigate the effects of an additional direction specification component of point & teleport. Since this direction specification component exerted an additional cognitive load into the use of the same technique, which was recommended to be avoided for individuals with ASD in the literature, it was only evaluated by neurotypical individuals. An immersive virtual maze environment was developed and a user study was performed with 16 neurotypical users. The results indicated that the additional direction specification feature did not improve the user experience.