The fabrication of evermore sophisticated miniaturized soft robotic components made up of Electro-Active Polymers (EAPs) is constantly demanding parallel development from the simulation point of view. The incorporation of crystallographic anisotropic micro-architectures, within an otherwise nearly uniform isotropic soft polymer matrix, has shown a great potential in terms of advanced three-dimensional actuation (i.e., stretching, bending, twisting), specially at large strains, that is, beyond the onset of geometrical instabilities. To accommodate for this response, we develop a phenomenological invariant-based polyconvex transversely isotropic framework for the simulation of EAPs at large strains. We show the existence of a solution and we also present various computational examples. Finally, we mention possible extensions to non-polyconvex material models.
This is a joint work with A.J. Gil (Swansea), M. Horak (Prague), and R. Ortigosa (Cartagena).