Fractional Order Control of a Robot System Driven

by DC Motors

Mihailo Lazarević

This paper presents the new algorithms of  PID control based on fractional calculus (FC) and an optimal procedure in the position control of a 3 DOF robotic system driven by DC motors. The objective of this work is to find out the optimal settings for a fractional controller in order to fulfill the proposed design specifications for the closed-loop system, taking advantage of the fractional orders,  and . The effectiveness of the suggested optimal fractional PID control is demonstrated with a suitable robot with three degrees of freedom as an illustrative example. In addition, this paper proposes a robust fractional-order sliding mode control of a 3-DOF robot system driven by DC motors. Primarily, a conventional sliding mode controller based on a  sliding surface is designed. Numerical simulations have been carried out to show the proposed control system's robustness properties as well as the significance of the proposed control which resulted in reducing output oscillations (chattering-free) of the given robot. The simulations also include a comparison of the fractional-order  sliding mode controller with the standard PD sliding-mode controller.

Key words: robots, DC motor, robust control, control algorithm, PID algorithm, fractional order control, vibration setting.