A Motion Tracker Using High-Accuracy AR Markers for On-site Motion Analysis

Motion analysis of human body is indispensable for design and evaluation of assistive technologies. Especially, on-site analyses, which are conducted not in experimental environments but in life circumstances, are important to develop truly beneficial assistive technologies. We developed a portable motion tracking system using high-accuracy AR markers. It enables easy measurement of 6-DOF (six degrees of freedom) motion of multiple tracking points by a single camera. The pose estimation errors are about 5 [mm] in location (depth) and about 2 [deg] in orientation. We applied the prototype of the motion tracker to the on-site motion analysis tasks, and demonstrated its availability in the evaluation of assistive technologies.