An Optimal Fractional Order PIλDμ For Robotic Manipulators Control Under Constrained Torque.

In robotic applications, the correct execution of a task can be a challenge for robotics experts. Therefore, it is necessary to implement a robust control structure for trajectory tracking. This paper proposes a robust control design to track the trajectory of an industrial robot via a fractional order PID controller with the Computed Torque Control (CTC) technique based on the Grey Wolf Optimizer (GWO). To examine the proposed robust control, the Fanuc 710ic/70 robot manipulator model is used as a case study. To begin with, the dynamic formulation of the robot is described. Then, with respect to the control design, the CTC controller that helps overcome the nonlinearity problem of the system is designed to improve the tracking performance. It is proposed to combine the fractional order PID with the CTC technique. This hybridization increases the performance of the control strategy and overcomes external disturbances, sensor noise suppression and especially input control constraints. Typically, FOPID controller parameters are set without considering the constraints of the actuator control inputs. Therefore, it affects its performance over time. To solve this problem, the controller parameters are updated online and optimized according to the input constraints using the GWO technique. The effectiveness of the proposed control strategy is demonstrated by the simulation results in terms of stability, trajectory tracking and compliance with limited inputs. [ABSTRACT FROM AUTHOR]