Torque sensor based robot arm control using disturbance observer

In this paper, a robust torque control method is proposed for a robot arm which is equipped with joint torque sensor. The proposed controller is used to control the joint torque and make it to be equal with the torque controller reference input torque. A flexible joint robot model will be introduced to model the robot arm system. The disturbance observer scheme is used to reduce the disturbance effects on the system. The PI torque controller is implemented using the characteristics of disturbance observer. The performance of the proposed controller is demonstrated through experiments with a one degree of freedom robot arm.