Enhancing the deformation range of ionic polymer metal composites through electrostatic actuation

The large range of deformations of ionic polymer metal composites (IPMCs) has often been proposed as a key advantage of these soft active materials. Nevertheless, many applications in soft robotics still cannot be addressed by current IPMC technology, demanding an even wider deformation range. Here, we empirically demonstrate the feasibility of integrating electrostatic actuation to enhance IPMC deformations. Through the use of external contactless electrodes, an electrostatic pressure is generated on the IPMC, thereby magnifying the deformation elicited by the small voltage applied across its electrodes. A mathematical model is established to predict the onset of the pull-in instability, which defines when electrostatic actuation can be effectively utilized to enhance IPMC performance.