Disambiguating touch with a smart-ring

Capacitive touchscreens have changed the way in which people interact with computational devices. In fact, direct touch input on screens is immediately understandable and appealing to both novice and advanced users and, more importantly, it leverages people's natural ability to use multiple fingers for input gestures. However, currently off-the-shelves touchscreens are unable to disambiguate among different fingers or to determine whether different touch-points belong to the same user, reducing the expressiveness of finger touches to that of multiple pointers. In this paper, we propose to augment human touch using a smart-ring. When the finger wearing the ring is in contact with the touchscreen, a unique ID is transmitted through vibration patterns from the ring to the touched device. It therefore becomes possible to distinguish touch between different users, or to associate different meanings to different touches for the same user. In this paper, we explore this design space and present a set of applications to demonstrate the feasibility of this technique.