I-PD Motion Control Scheme for Rigid Robotic Manipulators

Although the problem of controlling the motion of rigid robotic manipulators is a well-studied classical problem, a nouvelle method is presented in this article and demonstrated to have its own merits. This paper proposes a simple linear integral control scheme without gravity compensation. A PID controller is split into two parts: integral in the outer loop that works on the tracking error and a PD in the inner loop for stabilization and pole placement. A simulation study is performed to compare the performance of different existing methods with the proposed scheme. For this, the PUMA-560 manipulator arm is selected and a motion benchmark is designed. MATLAB/SIMULINK results show that the performance of the proposed method is comparable to that of inverse-dynamics method with the advantage of not having to compute the model online.