Modelling and simulation of a commercially available dielectric elastomer actuator

TL;DR

This paper develops a control-oriented model for a commercial dielectric elastomer actuator, demonstrating that a simplified elastic model suffices for control, while a more complex Kelvin-Maxwell model captures detailed dynamics effectively.

Contribution

It presents a systematic approach to model a commercial DEA using minimal assumptions, comparing static and dynamic models, and identifying the Kelvin-Maxwell model as optimal for detailed dynamics.

Findings

Hooke's law suffices for static description.

No viscoelastic model needed for control purposes.

Kelvin-Maxwell model with three Maxwell elements offers good accuracy and efficiency.

Abstract

In order to fully harness the potential of dielectric elastomer actu-ators (DEAs) in soft robots, advanced control methods are need-ed. An important groundwork for this is the development of a control-oriented model that can adequately describe the underly-ing dynamics of a DEA. A common feature of existing models is that always custom-made DEAs were investigated. This makes the modelling process easier, as all specifications and the struc-ture of the actuator are well known. In the case of a commercial actuator, however, only the information from the manufacturer is available and must be checked or completed during the modelling process. The aim of this paper is to explore how a commercial stacked silicone-based DEA can be modelled and how complex the model should be to properly replicate the features of the actu-ator. The static description has demonstrated the suitability of Hooke's law. In the case of dynamic description, it is shown that no viscoelastic model is needed for control-oriented modelling. However, if all features of the DEA are considered, the general-ized Kelvin-Maxwell model with three Maxwell elements shows good results, stability and computational efficiency.