Design of a robust quantitative feedback theory position controller for an ionic polymer metal composite actuator using an analytical dynamic model

Abstract

Nowadays, ionic polymer metal composite actuators are widely used in many fields such as biometric, biomedical, and micro-manipulator devices. Although extensive research exists on control of the ionic polymer metal composite actuators, not much research has been done on robust control considering the nonlinear dynamics of the ionic polymer metal composite. In this study, for the first time, a closed-loop robust controller based on quantitative feedback theory is designed to overcome the actuation performance degradation of the ionic polymer metal composite actuators. First, an analytical electromechanical model is developed to fully describe dynamics of the flexible ionic polymer metal composite actuator. The model is based on the Euler–Bernoulli beam theory and includes structural damping to model viscoelastic behavior of the ionic polymer metal composite actuator. Considering the highly nonlinear and uncertain dynamics of the ionic polymer metal composite actuator, a feedback controller based on quantitative feedback theory is designed to suppress the arbitrary external disturbances and consistently track desired input. Results indicate that the robust quantitative feedback theory control techniques can significantly improve the ionic polymer metal composite performance against nonlinearity and parametric uncertainties.

Challenges and Perspectives in Control of Ionic Polymer-Metal Composite (IPMC) Actuators: A Survey

“…In [69] and [70] a robust controller based on the quantitative feedback theory was employed for position tracking of the IPMC actuator. The quantitative feedback theory is well suited for systems with large parameter uncertainties.…”

“…The quantitative feedback theory is well suited for systems with large parameter uncertainties. In [69] the second-order transfer function served as a model in the controller design, whereas in [70] for this purpose a nonlinear electromechanical model of the IPMC was developed and then reduced to a family of the fourth-order linear uncertain transfer functions.…”

A QFT Robust Controller as a Remedy for TRMS

“…Desired timedomain responses are translated into frequency domain tolerances, which lead to bounds (or constraints) on the loop transmission function. The design process enables the designer to a trade-off between compensator complexity and system performance (Gharib & Moavenian, 2016;Jahanpour et al, 2015;Moavenian et al, 2011;Moeinkhah, et al, 2014).…”

Robust super-twisting sliding mode controller with state observer for position tracking of ionic polymer–metal composite actuators

“…Open-loop position response of an IPMC is not repeatable, and it is difficult to maintain its tip displacement at a desired position. Thus, a closed-loop control scheme is necessary to guarantee proper functioning and reliability (Moeinkhah et al, 2014).…”

“…First, linear control methodologies, such as proportional–integral–derivative (PID) controller (Richardson et al, 2003) and linear quadratic regulator (LQR) controller (Mallavarapu and Leo, 2001), have been applied. To conquer the highly nonlinear and uncertain dynamics of the IPMC actuators, advanced control approaches, such as H ∞ control (Chen and Tan, 2008), adaptive control (Brufau-Penella et al, 2008), robust quantitative feedback control (Ahn et al, 2010; Moeinkhah et al, 2014), operator-based control (Deng and Wang, 2012), and fuzzy logic control (Goharimanesh et al, 2017), have been applied. Yet, now some sliding mode strategies have also been applied to control IPMC actuators.…”