Demonstrating Dothraki: Tracking Tangibles Atop Tabletops Through De-Bruijn Tori

Abstract

We demonstrate usage examples and technical properties of 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. The MuC demonstration encompasses four separate demos that showcase typical application scenarios and features: a magic lens, two tangibles that know each others relative position, a simple geometry application that measures distances and angles, and tangibles that know on which of multiple surfaces they have been placed.