Hover Pad: interacting with autonomous and self-actuated displays in space

Handheld displays enable flexible spatial exploration of information spaces -- users can physically navigate through three-dimensional space to access information at specific locations. Having users constantly hold the display, however, has several limitations: (1) inaccuracies due to natural hand tremors; (2) fatigue over time; and (3) limited exploration within arm's reach. We investigate autonomous, self-actuated displays that can freely move and hold their position and orientation in space without users having to hold them at all times. We illustrate various stages of such a display's autonomy ranging from manual to fully autonomous, which -- depending on the tasks -- facilitate the interaction. Further, we discuss possible motion control mechanisms for these displays and present several interaction techniques enabled by such displays. Our Hover Pad toolkit enables exploring five degrees of freedom of self-actuated and autonomous displays and the developed control and interaction techniques. We illustrate the utility of our toolkit with five prototype applications, such as a volumetric medical data explorer.