Accurate and Low-Latency Sensing of Touch Contact on Any Surface with Finger-Worn IMU Sensor

Head-mounted Mixed Reality (MR) systems enable touch in­teraction on any physical surface. However, optical methods (i.e., with cameras on the headset) have difficulty in determin­ing the touch contact accurately. We show that a finger ring with Inertial Measurement Unit (IMU) can substantially im­prove the accuracy of contact sensing from 84.74% to 98.61% (f1 score), with a low latency of 10 ms. We tested different ring wearing positions and tapping postures (e.g., with different fingers and parts). Results show that an IMU-based ring worn on the proximal phalanx of the index finger can accurately sense touch contact of most usable tapping postures. Partici­pants preferred wearing a ring for better user experience. Our approach can be used in combination with the optical touch sensing to provide robust and low-latency contact detection.