Marker-less tracking of human movement using Microsoft Kinect

This study quantifies the accuracy of the Microsoft Kinect in two motions. Ten participants were asked to perform reaching and throwing actions which were recorded simultaneously by a Kinect and a motion analysis corporation (MAC) capture system. Elbow and shoulder angles were calculated for both motions. NITE (PrimeSense, USA) and IPI soft tracking algorithms were used. NITE tracking had an average maximum error of 32.4° for the elbow and shoulder in the reach motion and 95.3° in the throwing motion. IPI soft had equivalent maximum error values of 22.3° and 43.0° respectively. While accuracy isn’t high, and suffers in high speed motions, the advantages offered by markerless tracking, low cost and zero calibration make the Kinect potentially valuable for motion analysis in coaching, clinical and educational domains