Toward an Affordable Multi-Modal Motion Capture System Framework for Human Kinematics and Kinetics Assessment

Abstract

The present study aims at designing and evaluating a low-cost, simple and portable system for human kinematics (joint angles) and kinetics (joint torques) motion assessment. The system is based on a single camera, a set of customized markers, low-cost inertial measurement units and an affordable Wii Balance board. The automatically detected and tracked marker positions and orientations were used synchronously with other sensors data as inputs to an Extended Kalman Filter based on a biomechanical model of the investigated tasks. The method was validated with arm motions and with lower-limb motions of a subject wearing an exoskeleton. External ground reaction forces measured with a Wii Balance board were compared to the estimated ones based on the proposed low-cost system. Comparative analysis shows good accuracy with a low average NRMS error.