Smooth touch and force control to unknown environment without force sensor for industrial robot

This paper proposes a new smooth touch control to unknown environments for industrial robot. The touch control is one of the useful methods for the smooth force control. Many applications of the manipulator should have a high stiffness position control method. However, the controller has no flexibility to the environments. Therefore, a method of high performance force control is an important factor for many applications. For this purpose, this paper proposes a new force control structure based on I-PD force controller and disturbance observer. The experimental results in this paper confirm that the proposed method has fine validity of smooth touch control to unknown environments such as concrete, foamed styrol and cardboard box by using the tested 3-DOF industrial manipulator.