Development of a lower extremity exoskeleton system for human-robot interaction

A human-robot interaction system should not restrain the human motion, but just provide appropriate assistive torque according to the operator´s intention. It requires a very precise actuating system which can realize zero impedance between the human and the robot. In the proposed system, the actuator module employing a series elastic actuator (SEA) mechanism is developed, which contains a torsional spring between an actuator and a human joint. Four actuator modules are applied to assist the operator´s lower extremity movement in the hip joints and the knee joints on the sagittal plane.