Precise Position Control of Quanser Servomotor using Fractional Order Fuzzy PID Controller

Abstract

Sophisticated automation is dependent upon industrial robots with precise position control servomotors. In the present work, a fractional order fuzzy PID controller (FOFPID) was designed to improve the position control response of a rotary servo system. The control errors and their fractional derivatives were applied as input scaling factors to the fuzzy logic controller (FLC). Fuzzy inference system (FIS) was employed to restrict performance indices in control signals. FOFPID performance for a Quanser servomotor was compared against PID, fractional order PID and fuzzy PID (FPID) controllers in terms of both simulations and hardware implementation. The controller performance evaluation metrics included time domain characteristics such as rise, peak, settling times and over / undershoots. The integral absolute and integral time absolute errors were also evaluated for comparisons among the different controllers. Results establish that only the FOFPID controller achieves zero percent over and undershoots. It also attains better set point tracking over other controllers. Thus, FOFPID controller is the key to precision robotics in the smart factories of tomorrow.