Performance Analysis and Experimental Validation of 2-DOF Fractional-Order Controller for Underactuated Rotary Inverted Pendulum

Abstract

Several numbers of controllers are developed and implemented to enhance the performance of rotary single inverted pendulum (RSIP). This paper addresses a new two-degree-of-freedom (2-DOF) fractional control strategy for RSIP, which is a composition of feedback and feed-forward paths. Primary controller relates the perturbation attenuation, while the secondary controller is accountable for set point tracking. The pole placement technique is used for the design of 2-DOF proportional integral derivative (2-DOF PID) controller. In order to intensify the potentiality of 2-DOF PID controller, it is supplemented with fractional calculus. The tuning of fractional parameters is done by frequency domain analysis using the Nyquist plot. The proposed 2-DOF fractional-order PID controller is materialized on RSIP system which out turns the outstanding experimental results for both stabilization and trajectory tracking tasks. The system is investigated for stability, sensitivity and robustness, which confirms the ability of the proposed controller to reject the external random perturbations.