Anisotropic electrostatic actuation

We examine the theoretical basis for the enhancement of classical, dielectric actuation by first imposing an elongation ('pre-strain') in one of the two directions in the plane of the working elastomeric filling between flexible electrodes. Such anisotropic actuation has been shown experimentally to be effective in delivering more mechanical work from a given applied voltage. A wrinkling instability in the in-plane direction perpendicular to the load limits the applicability of this strategy. It is shown to intervene before pull-in.