Muscle Extension Model for FES-Assisted Knee Swinging Ergometer for Stroke Patient

This work is focused on the development of physiological and mathematical model of muscle extension induced by FES-assisted knee swinging ergometer. A muscle model composed of muscle activation, muscle contraction and body segmental dynamics is developed to perform full knee extension. The developed muscle model is then incorporated with a humanoid model and a knee swinging ergometer model to perform simulation of FES-assisted knee swinging exercise. The developed humanoid model possesses the characteristics of stroke patient while the knee swinging ergometer was developed with the ability of utilizing the non-paretic knee in assisting the swinging of the paretic knee. The developed muscle model is evaluated under the dynamic simulation of FES-assisted knee swinging ergometer. The active torque and knee trajectories are recorded and the results shows that the design of knee swinging ergometer had successfully reduced the required stimulation pulse width in performing full knee extension. It is also suggested that the muscle model developed can be used for future analysis and control development of FES-assisted knee swinging ergometer for stroke patient.