Motion Calculation for Human Lower Extremities Based on EMG-Signal-Processing and Simple Biomechanical Model

Abstract

In this paper we present a way to calculate the motion of the human lower ex-tremities online based on surface EMG signals emitted by the activated muscles. The EMG signal evaluation is directly integrated into the control loop of the model to allow for more flexible and spontaneous movements than with predefined trajectories. The algorithm imple-ments a simple biomechanical model composed of bones and muscles. An additional stability controller modifies the torques in the ankle, knee and hip joints to keep the model in a stable pose. The proposed method will be part of a control system for an exoskeleton robot where the movement of the model will be interpreted as the intended movement of the operator. The performance of the presented method was investigated on the stand-to-sit movement.