Modeling of IPMC actuator using cascaded black box model of Preisach operator and fuzzy NARX structure

An ionic polymer metal composite (IPMC) actuator is an Electro-Active Polymer (EAP) that bends in response to a small applied electrical field as a result of mobility of cations in the polymer network. This paper proposes a cascaded model of Preisach operator and fuzzy Nonlinear Auto Regressive Exogenous (NARX) structure for modeling and identifying the nonlinear behavior of on type IPMC actuator. Firstly, a set of open loop input voltage signals were applied to the IPMC in order to investigate the IPMC bending actuation. Consequently, Secondly, a proper Preisach type fuzzy NARX model is developed with one input and one output to estimate the IPMC tip displacement. By employing the collected training data, an identification scheme based on incorporation of least square method and Particle Swarm Optimization (PSO) algorithm is then carried out to tune the model parameters.