A Muscle Tension Estimation Method by using Mechanical Impedance of Human Knee Joint During Training by Manipulator

We have developed a manipulator for supporting human lower limb rehabilitation that enables to estimate muscular tension of protagonistic muscles of healthy persons during exercise. Non-healthy persons train while adjusting the antagonistic muscles due to damaged muscles. In order to increase estimation accuracy of antagonistic muscle, a method to derive each joint torque due to protagonistic muscles and antagonistic muscles through estimating joint mechanical impedance is proposed, where joint viscosity and stiffness are proportional to sum of protagonistic muscle force and antagonistic muscle force. From optimization algorithm applied to each joint torque due to protagonistic muscles and antagonistic muscles, muscle tension for each seven muscles related to knee joint is estimated. The waveform is similar to the one from EMG for both protagonistic muscles and antagonistic muscles.