Viscoelastic modelling and experimental results of a dielectric electro‐active polymer diaphragm actuator

Abstract

AbstractCommon actuating principles e.g. solenoids or piezo‐elements have mostly exploited their potential as electromechanical transducers. A new technology based on Dielectric Electro‐active Polymers (DEAPs) enables major progress in efficiency and functionality for actuators. In order to use the advantages of this new technology in a feasible application, a silicone based DEAP diaphragm actuator was tested experimentally. Here, the mechanical properties of the fundamental parts of the DEAP diaphragm actuator, namely the stressstrain behaviour of an equibiaxially pre‐stretched hyperelastic polymer and the mechanical response of a DEAP diaphragm actuator, were determined by appropriate test benches.The investigated DEAP diaphragm actuator consists of a dielectric, which corresponds to a thin elastic silicone film sandwiched between two compliant electrodes. Furthermore, DEAPs are pre‐stretched, actually up to five times their in‐plane dimensions, in order to improve their performance. In that context, the influence of the pre‐stretched state on the actuator performance was investigated. In addition, a viscoelastic finite‐element model of the electromechanical system has been developed and validated with the experimental results. The mechanical part of the DEAP diaphragm actuator was realized with an incompressible isotropic elastic model, whereas the electrical part was approximated with a circular parallel‐plate capacitor. (© 2014 Wiley‐VCH Verlag GmbH & Co. KGaA, Weinheim)