A sensor-to-segment calibration method for motion capture system based on low cost MIMU

The calibration for aligning wearable sensors with human body segments plays an important role in the realization of MIMU-based motion capture systems. This paper presents a novel calibration method using MIMU's 3-axis accelerometer, 3-axis magnetometer, and smartphone's compass (or commercial compass), which allows non-experts to easily implement the calibration procedure, because the subjects only need to face north and stand still for a few seconds after correction of the MIMU's magnetometer. The positions of the correction of a magnetometer in both indoor and outdoor environments were determined through experiments. Furthermore, the accuracy of the proposed calibration method, and the influence of the sensor's mounting positions were validated by an optical measurement system (NDI Polaris Spectra System). Finally, the accuracy of this method was evaluated by the localization and posture capture for a pedestrian. Experimental results demonstrated that the proposed calibration method can be effectively applied to human motion capture system.