Comparative study between PI and sliding mode controllers for flexible joint manipulator driving by Brushless DC motor

In this paper, a comparison between PI and sliding mode control is proposed for the control for flexible joint manipulator driving by Brushless DC motor (BDCM)to improve the performance in the presence of errors in the parameters identification. First, the model of flexible joint manipulator was presented. Then, a PI control is studied and designed for tracking problem of the single flexible joint manipulator. Besides, sliding mode control is studied and designed also for the same problem. Finally, those strategies of control are implemented in the Matlab-Simulink environment to show the high performances and a comparative study of the different strategies of PI and sliding mode controllers was achieved. Although the presence of flexibility in the joint, the simulation results show the high performances of sliding mode controller by converging the error to zero and guaranteeing stability of the robot.