Please note: This PhD defence will take place in DC 2314.
Futian Zhang, PhD candidate
David R. Cheriton School of Computer Science
Supervisors: Professors Jian Zhao, Keiko Katsuragawa
While unimanual input is widely adopted in Virtual Reality/Augmented Reality systems with head-mounted displays, some of them still require multiple steps to complete. Although the total task completion time may not be long, a high frequency of usage will still increase the overall activity duration and reduce user efficiency. However, when the user is executing unimanual input with the dominant hand, the non-dominant hand is mostly left unused, which could potentially help execute some steps synchronously with the dominant hand, while maintaining an intuitive user experience. By harnessing the capabilities of both hands simultaneously, bimanual input can extend the interaction dimension, complementing existing unimanual methods for elementary tasks, like pointing, locomotion, and command access, which are frequently used in short-time tasks. This thesis, Concerto, explores how bimanual input can be leveraged to improve the performance of elementary tasks.
Three projects examine how bimanual input can improve efficiency in VR/AR.
In the first project, I present a new interaction technique called Conductor, which aims to improve points, one of the fundamental tasks in VR/AR, by leveraging bimanual input. Conductor is an intuitive, intersection-based 3D pointing technique where users utilize their non-dominant hand to adjust the cursor distance along a ray while pointing with their dominant hand. I evaluate Conductor against Raycursor, a state-of-the-art VR pointing technique, and demonstrate that Conductor offers superior performance in selection tasks.
In the second project, I examine how Conductor can be adapted to another critical VR task: locomotion. I introduce Fly The Moon To Me (or Locomoontion for short), a technique that allows users to create a preview copy of the object they wish to approach, reposition it ideally using Conductor, and then seamlessly align the original object with this preview, along with the rest of the virtual environment. A teleportation experiment, in which participants locate a box and place another smaller box inside it, shows that Locomoontion is faster and requires less physical effort than the traditional Point & Teleport method, even with the Point & Tug modification.
In the third project, I explore how bimanual input can improve command selection tasks through shortcut mechanisms. I introduce the Drum Menu, a shortcut menu inspired by traditional marking menus, featuring three input methods with both unimanual and bimanual options for 4-item and 8-item VR controller layouts. Users can select commands by rotating the joystick, drawing a stroke, or pointing in specific directions. Bimanual input provides simultaneous access to two menu levels. A controlled user study shows that bimanual variants are faster than unimanual ones in the 4-item layout. Users favour the bimanual joystick menu for the 4-item layout, though the 8-item layout shows increased error rates for advanced users.
Together, this thesis pushes the boundaries of bimanual input, employing new interaction techniques to enhance the productivity of VR/AR users.