Numerical simulation of dynamic electro-mechanical response of ionic polymer-metal composites

Ionic Polymer-Metal Composites (IPMC) is an emerging class of Electro-Active Polymer (EAP) materials. IPMC has attractive features, such as high sensitivity and light weight, which are useful for developing novel designs in the fields of bionic actuators, artificial muscles and dynamic sensors. A Finite Element (FE) model was developed for simulating the dynamic electro-mechanical response of an IPMC structure under an external voltage input. A lumped Resistor-Capacitor (RC) model was used to describe the voltage-to-current relationship of a Nafion IPMC film for the computation of electric field intensity. Moreover, the viscoelastic property of the IPMC film was considered in the model and the non-uniform bending behavior was also taken into account. Based on the proposed model and the assumption that the thicknesses of the two electrodes are the same and uniform, the optimal coating thickness of the IPMC electrode was determined. It was demonstrated that the dynamic electro-mechanical response of the IPMC structure can be predicted by the proposed FE model, and the simulation results were in good agreement with the experimental findings.