Finite element modeling and simulation of a soft array of dielectric elastomer actuators

Dielectric elastomers (DEs) consist of thin membranes of dielectric material (e.g., silicone) coated with compliant electrodes. When subject to a high voltage, a DE undergoes an in-plane expansion which can be used for actuation purposes. Nowadays, most of the applications of DE actuators (DEAs) are based on single-degree-of-freedom systems. If many DEA elements are combined together in an array-like structure, a new generation of distributed and cooperative micro-actuators can be developed, with potential applications in fields such as soft robotics, distributed acoustics, and wearables. In this work, we present the first steps towards the development of such types of cooperative DEA systems. In particular, we report a finite element (FE) simulation study conducted on a one-dimensional array of silicone-based DEAs. Individual activation of each actuator in the array can be performed in an independent way, thus allowing to implement cooperative control paradigms. First, a FE model of the system is implemented in COMSOL environment and validated by means of experimental data. Then, a simulation analysis is conducted with the aim of understanding how the system parameters (e.g., geometry, pre-stress, actuators spacing) affect the overall electro-mechanical performance. The presented analysis will serve as a reference for the development of distributed cooperative DEA systems.