The influence of walking speed on muscle activity of thigh and application in prostheses control

Changes in walking speed may eventually result in modifications of the patterning of muscle activity. The surface electromyography (EMG) signals provide easy and noninvasive access to physiological processes that cause the contraction of muscles. The influence of walking speed on muscle and EMG activity of amputee´s thigh was analyzed, the speed pattern recognition approach based on the combination of surface EMG signal and knee angle was applied to recognize the walking speed of amputee, and the walking speed control strategy of above knee prostheses was proposed. The result of experiment demonstrated that the phasing of muscle activity remained relatively stable over every walking speed despite substantial changes in EMG´s amplitude. Adjusting the swing velocity of prosthesis knee can improve the performance of prosthesis and decrease the energy consumption. The outcome of this investigation could promote the future design of neural-controlled artificial legs.