Robust Control Design of 6-DOF Robot for Nuclear Power Plant Dismantling

Controller design for robotic manipulator in a nuclear environment has been a challenging task for more than a decade. In this paper three different control techniques were proposed which include PID control, sliding mode control (SMC) and sliding mode control with sliding perturbation observer (SMCSPO). Dynamic modeling of the system was done using the Lagrange approach. The trajectory was planned for manipulator's end-effector, then trajectory for each joint was computed. Then control algorithms were designed and implemented in MATLAB/Simulink. The simulation results illustrated that PID is a linear control, therefore, when controlling the system with uncertainties the performance of PID is not good. Sliding mode control is a robust non-linear control and have good performance characteristics but information of upper bound of perturbation is necessary. To overcome this problem SMCSPO a robust control with disturbance rejection logic has been implemented and result shows that SMCSPO performance is better than SMC and PID in the presence of uncertainties and external disturbance due to disturbance compensation.