Avoiding the pull-in instability of a dielectric elastomer film and the potential for increased actuation and energy harvesting

Abstract

Pull-in instability often occurs when a film of a dielectric elastomer is subjected to an electric field. In this work, we concoct a set of simple, experimentally implementable, conditions that render the dielectric elastomer film impervious to pull-in instability for all practical loading conditions. We show that a uniaxially pre-stretched film has a significantly large actuation stretch in the direction perpendicular to the pre-stretch and find that the maximal specific energy of a dielectric elastomer generator can be increased from 6.3 J g⁻¹ to 8.3 J g⁻¹ by avoiding the pull-in instability.