FaceWidgets: Exploring Tangible Interaction on Face with Head-Mounted Displays

We present FaceWidgets, a device integrated with the backside of a head-mounted display (HMD) that enables tangible interactions using physical controls. To allow for near range-to-eye interactions, our first study suggested displaying the virtual widgets at 20 cm from the eye positions, which is 9 cm from the HMD backside. We propose two novel interactions, widget canvas and palm-facing gesture, that can help users avoid double vision and allow them to access the interface as needed. Our second study showed that displaying a hand reference improved performance of face widgets interactions. We developed two applications of FaceWidgets, a fixed-layout 360 video player and a contextual input for smart home control. Finally, we compared four hand visualizations against the two applications in an exploratory study. Participants considered the transparent hand as the most suitable and responded positively to our system.