Harnessing Dielectric Breakdown of Dielectric Elastomer to Achieve Large Actuation

It is an interesting open question how to achieve large actuation of a dielectric elastomer (DE). In many previous works, in order to harness snap-through instability to achieve large deformation, a reservoir was employed to assist the dielectric elastomer actuator (DEA) to optimize its loading condition/path, which makes the whole actuation system bulky and heavy. In this paper, we explore large actuation of a DE balloon with applications to a soft flight system. The balloon consists of two separate DEAs: The inner one is stiffer while the outer one is softer. The whole actuation system has a small volume and a low weight, but can achieve large actuation by harnessing dielectric breakdown of the inner elastomer. The volume induced by dielectric breakdown is more than 20 times the voltage-induced volume change of DEAs. The experiments demonstrate a soft flight system, which can move effectively in air by taking advantage of large actuation of this DE balloon. This project also shows that failure of materials can be harnessed to achieve useful functionalities.