A biped humanoid robot which can be used as a human motion simulator, meaning the robot can perform equal exercises with human beings tests welfare equipment which are under development in place of a human, and provides quantitative data. The frameworks of the robot are mainly made from aluminum alloy in order to realize a light weight, high stiffness, and a wide movable range robot. Each actuator system of the joint consists of a DC motor, a harmonic drive gear, a lug belt, and two pulleys. Thi