The exerting muscle forces of the arms, waist and legs of the care personnel are detected by the muscle hardness sensors placed on the care personnels upper arms, on the legs above the knees and on the back above the hip. The output signals of the sensors are transmitted to the embedded microcomputer. The embedded microcomputer calculates the necessary joint torques for maintaining the position of lifting a patient and the torques are combined with the output signals of the muscle sensors to make control signals inputted into the air pump driving circuits. Then the supply of air flow to the cuff changes in accordance with the necessary joint torque. The necessary joint torques and the muscle forces driving the joints are estimated by computing the equations of body mechanics, as a function of the joint angles. The joint angles are detected by potentiometers.

Fig.1 Construction of Power Assist Suit