Soft elastomers that can exhibit extremely large deformations under the action of an electric field are essential for applications such as soft robotics, stretchable and flexible electronics, energy harvesting among others. The critical limiting factor in conventional electro-actuation of such materials is the occurrence of the so-called pull-in instability. In this work, we demonstrate an extraordinarily simple way to coax a dielectric thin film towards a symmetry-breaking pitchfork bifurcation state while avoiding pull-in instability. Through the nonlinear interplay between the two bifurcation modes, we predict electro-actuation strains that exceed what is conventionally possible by 200%, and at significantly lower applied electric fields.

在电场作用下会表现出极大变形的软弹性体对于诸如软机器人，可伸缩和柔性电子，能量收集等应用至关重要。在这种材料的常规电致动中的关键限制因素是所谓的拉入不稳定性的发生。在这项工作中，我们演示了一种极简单的方法来将介电薄膜哄骗到对称的干草叉分叉状态，同时避免拉入不稳定性。通过两个分叉模式之间的非线性相互作用，我们预测电致动应变将超过传统可能的电致应变200％，并且施加的电场明显降低。