Dynamic Analysis and Active Control of a Dielectric Elastomer Balloon Covered by a Protective Passive Layer

Abstract

Dielectric elastomer (DE) balloons are intensively developed as sensors, actuators, and generators.  To ensure electrical safety, a DE balloon can be covered by an external passive layer. In this paper, the dynamic behaviours and active control for the DE balloon coupled with the passive layer are investigated. Based on the Hamilton’s principle, the dynamic model of the DE balloon covered by the passive layer is derived. With this coupled model, we demonstrate that three typical dynamic responses can appear and the transition among these dynamic behaviours can be achieved by altering the properties of the passive layer. The introduction of the passive layer is able to induce undesirable dynamic behaviours, which require to be controlled. Thus, we present two methods of control including proportional-derivative (PD) control and iterative learning control (ILC). We demonstrate that the undesirable dynamic responses can be effectively eliminated by the proposed methods of control. Particularly, control errors can be reduced by 2 or 3 orders of magnitude using the latter control method. We hope that the present analysis can improve the understanding of dynamic behaviours of a DE balloon covered by a passive layer and promote the control of undesirable dynamic responses.