Motion Control of Flexible Joint

Abstract

This paper proposes an advanced control of flexible joint. Industrial robots generally have the elastic elements in the torque transmission. The torsional vibration is caused when the motion response is fast. This vibration deteriorates the motion of the joint. In the flexible joint control, it is important to increase the stability of the system in the wide motion range. In the proposed method, to obtain the stability of the system, state feedback is applied. For the purpose, the concept of an acceleration controller of the motor axis is applied. This controller is realized by the disturbance observer. The proposed method brings more robust control and the paper also shows the experimental results.