Fractional-order modeling and control of ionic polymer-metal composite actuator

Abstract

Fractional-order (FO) calculus-based modeling and control of ionic polymer-metal composite (IPMC) actuators is studied in this paper. Since IPMC actuators exhibit FO dynamics, a suitable compensator must be designed for control thereof. In this work, we employ FO proportional-integral-derivative (FOPID) controllers, as well as FO inverse model (FOINVM) based control. Only open-loop control methods are considered. Since process model-based control is used, the IPMC actuator is modeled using a FO transfer function, whereby a process identification is performed. Additionally, the designed controller is implemented in hardware that allows the whole control system to be easily miniaturized and considered in embedded applications. All of the experiments presented in this paper are carried out with the IPMC actuator placed in a controlled inert environment. The results of the real-time control experiments are presented and discussed and indicate the validity of the considered modeling and control approach.