Robust Trajectory Tracking Control of a Robotic Manipulator Using Fractional Order PID Controller

Abstract

This paper investigates the efficiency of FractionalOrder Proportional-Integral-Derivative (FOPID) control of a 2-degree-of-freedom (2-DOF) robotic manipulator for highprecision trajectory tracking. Although the standard PID controller offers a performance baseline, its integer-order structure often fails to adequately compensate for the inherent nonlinearities and dynamic coupling in multi-joint manipulators under real-time operation. By incorporating fractional-order calculus, the proposed FOPID controller provides additional tuning parameters that substantially expand the optimization space. Additionally, we present a comparative study of both controllers under various dynamic tracking scenarios of a disturbed system. Our findings indicate that the enhanced flexibility of the FOPID structure facilitates a more robust and optimized control performance, resulting in superior tracking accuracy and improved disturbance rejection. The obtained results highlight the practical value of advanced control strategies in meeting the high-performance requirements of the next generation of autonomous systems.