This work investigates the characterization and modelling of hysteresis in a core-free dielectric electro-active polymer (EAP) tubular actuator. The overall hysteresis effect of the voltage driven system comprises the inherent hysteresis of the fabricated tubular actuator plus a time lag introduced by the associated power supply when charging and discharging the actuator. Specifically the dynamic asymmetric hysteretic model of the voltage driven tubular actuator is decomposed into two models in series, comprising the nonlinear static voltage-strain characteristic of the actuator and an approximate symmetric hysteretic characteristic. The Bouc-Wen model approach is popular in engineering because of its simple interpretation as a nonlinear black-box model, the relatively low number of parameters needed to describe it, and the availability of both optimization and least squares estimation approaches to identify model parameters from experimental data. A disadvantage of the Bouc-Wen modelling approach is that it cannot accurately model asymmetric hysteresis behaviour. The use of the decomposition approach allows the Bouc-Wen model to be used to describe the approximate symmetric hysteretic characteristic. The model parameters are identified using an evolutionary computational algorithm - particle swarm optimization (PSO). PSO is an evolutionary based optimization approach that has been shown to be superior to genetic algorithms.

Date Published: 6 April 2009
PDF: 9 pages
Proc. SPIE 7287, Electroactive Polymer Actuators and Devices (EAPAD) 2009, 728717 (6 April 2009); doi: 10.1117/12.815421

Published in SPIE Proceedings Vol. 7287:
Electroactive Polymer Actuators and Devices (EAPAD) 2009
Yoseph Bar-Cohen; Thomas Wallmersperger, Editor(s)