Accessible Calibration of Insole Force Sensors Using the Wii Balance Board for Kinetic Gait Analysis

This paper presents a novel calibration method of insole sensors to estimate vertical ground reaction force (vGRF) during walking using the Wii Balance Board (WBB) as an accessible alternative to costly force plates. The sensor forces were weighted using linear least-squares regression to fit to the measurements of the WBB during walking and standing. By comparison with force plates, the accuracies of the vGRF estimated by the method with walking through the WBB were equivalent to the force plate-based calibration. In addition, the method using standing on the WBB did not have large deteriorations when compared to the above methods.