Viscoelasticity Modeling of Dielectric Elastomers by Kelvin Voigt-Generalized Maxwell Model

Abstract

Dielectric elastomers (DEs) are polymer materials consisting of a network of polymer chains connected by covalent cross-links. This type of structural feature allows DEs to generate large displacement outputs owing to the nonlinear electromechanical coupling and time-dependent viscoelastic behavior. The major challenge is to properly actuate the nonlinear soft materials in applications of robotic manipulations. To characterize the complex time-dependent viscoelasticity of the DEs, a nonlinear rheological model is proposed to describe the time-dependent viscoelastic behaviors of DEs by combining the advantages of the Kelvin–Voigt model and the generalized Maxwell model. We adopt a Monte Carlo statistical simulation method as an auxiliary method, to the best knowledge of the author which has never reportedly been used in this field, to improve the quantitative prediction ability of the generalized model. The proposed model can simultaneously describe the DE deformation processes under step voltage and alternating voltage excitation. Comparisons between the numerical simulation results and experimental data demonstrate the effectiveness of the proposed generalized rheological model with a maximum prediction error of 3.762% and root-mean-square prediction error of 9.03%. The results presented herein can provide theoretical guidance for the design of viscoelastic DE actuators and serve as a basis for manipulation control to suppress the viscoelastic creep and increase the speed response of the dielectric elastomer actuators (DEA).

A Review on High‐Frequency Dielectric Elastomer Actuators: Materials, Dynamics, and Applications

“…This model could predict the dynamic response of the membrane and fitted the experiment well. Aiming to describe the behavior of a cylindrical DE more accurately, Nguyen et al [102] combined the advantages of the Kelvin-Voigt model and the Table 1. The summary of typical methods to enhance lifetime for DEAs and their corresponding reported life cycle or life endurance under a certain strain.…”

Characterizations and Inkjet Printing of Carbon Black Electrodes for Dielectric Elastomer Actuators

“…The real-time voltage was recorded in LabVIEW with an NI-9205 module (DAQ, National Instruments GmbH). A displacement laser (ILD 1420-10, Micro-Epsilon) was used to track the DEA actuation by monitoring the displacement of a tiny PDMS 52 that was placed at the edge of the DEA electrode (as shown in Figure S1c). The area strain/actuation (area strain = (A actuated − A initial )/ A initial × 100%) and voltage were plotted with the time.…”

The dissipative dynamic performances of dielectric elastomer actuator with viscoelastic effects

“…Gu [26] established a multi-relaxation time rheological model to accurately predict the electromechanical response of DEs. In a recently released study, Nguyen [27] combined the Kelvin-Voigt model and the generalized Maxwell model to derive the KV-GM model, which absorbed the advantages of both models. Compared with the experimental validation with limited waveforms and frequencies, the maximum prediction error is 3.762%.…”