Dothraki: Tracking Tangibles Atop Tabletops Through De-Bruijn Tori
Dennis Schüsselbauer, Andreas Schmid, Raphael Wimmer
Abstract
Tangibles are small, graspable objects that act as input devices or physical representations of digital data. Oftentimes, it is desirable to track the position of tangibles on a surface and their relation to each other. However, outside-in tracking techniques - such as capacitive touchscreens or cameras - require setting up elaborate infrastructure and are prone to occlusion or interference. We propose Dothraki, an inside-out tracking technique for tangibles on flat surfaces. An optical mouse sensor embedded in the tangible captures a small (36×36 pixel / 1×1 mm), unique section of a black-and-white De-Bruijn dot pattern printed on the surface. Our system efficiently searches the pattern space in order to determine the precise location of the tangible with sub-millimeter accuracy. Our proof-of-concept implementation offers a recognition rate of up to 95%, robust error detection, an update rate of 14 Hz, and a low-latency relative tracking mode.