Failure analysis of a dielectric elastomer plate actuator considering boundary constraints

Dielectric elastomer actuators, a promising transducer technology, have received much attention due to their high efficiency and large deformation. However, in addition to electrical breakdown, dielectric elastomer actuators may also be easily affected by electromechanical instability. These failure modes inhibit the full potential actuation of dielectric elastomers. This study examines the parametric range for which electromechanical instability can be avoided for a dielectric elastomer plate actuator while achieving large actuation. It is found that the electromechanical instability can altogether be eliminated by boundary constraints. With control of the boundary conditions, consideration should also be given to the possible mechanical buckling failure that may occur. Simulation results based on Gent constitutive model are presented to show how these failure modes can be controlled and to what extent the performance of the dielectric elastomer actuator can be improved. This work should provide a better understanding on how to achieve the desired actuation performance of dielectric elastomers, thus leading to a better and controlled design for the applications of these smart materials in transduction technologies.