Practical robust control for flexible joint robot manipulators

In this paper we proposed a practical robust controller which has simple structure, more easy tuning factor, and control forms having direct relation with control performance. This robust control is designed using the motor side dynamics directly. The design procedure consists of three parts. A model based computed torque control part to decrease stead-state errors, a feedback based control part to increase control accuracy, and robust control part to maintain the tracking performance using the nonlinear H-infinity control. The designed robust control is applied to a 6 DOF robot manipulator with joint flexibilities. The proposed robust controller has better tracking performance and advantage in its application.