Property of force-free control with independent compensation for inertia, friction and gravity of industrial articulated robot arm

Force-free control can realize the flexible motion of industrial articulated robot arms without any change of the built-in controller. In this paper, the force-free control was extended to realize the motion as if it were under the circumstance of any inertia, any friction and any gravity through the independent compensation of inertia, friction and gravity. The property of the force-free control with independent compensation was also investigated by the experimental study of an actual industrial articulated robot arm, where the external force was measured by the force sensor which was attached to the tip of the robot arm.