An estimation method of muscle forces for each muscle group using theory of functionally different effective muscles considering human dynamics

Although the effectiveness of biofeedback using an electromyogram (EMG) has been reported, it is seldom used in ordinary therapeutic exercise because it takes time to attach electrodes. Conventional muscle force estimation methods using joint torque take time in order to solve optimization problems. In order to make the computation time shorter, a method has been proposed, which converts tip force of limbs to each force of 6 muscle groups by using the FEM theory for 2D motion of 2 joints of limbs, which is given to each optimization problem. Since muscles exert not only tip force of limbs but also force due to dynamics such as inertia force and so on, estimation accuracy is not satisfactory. The new tip force which is sum of tip force of limbs and the tip force according to dynamics of limbs is given to the muscle force estimation method using the FEM theory. For the exercise using the manipulator for lower limbs, the estimation result of the proposed method is similar to Okuyama´s muscle force estimation method which uses joint torque considering dynamics of limbs while the computation time is shorter than the Okuyama´s method.