Design of a dielectric elastomer actuator driven pneumatic pump

Abstract

Dielectric elastomer actuators (DEA) enable to build compact, silent and lightweight systems capable of a large actuation bandwidth up to the kHz range. They consist of a thin elastomer film between two electrically conductive and flexible electrodes. If a high voltage is supplied to a DEA, the opposing electrical charges on the two electrodes result in electrostatic forces which produce a controllable deformation. This work presents a systematic design approach for the design of DEA driven pneumatic pumps for mobile applications. Due to the combination of large actuation bandwidth and the high compactness, DEA appear as highly suitable for designing pumps for such applications. Silicone based circular out-of-plane membrane DEAs (also referred to as cone DEAs) combined with biasing springs are studied in this work. A commercially available pump mechanism, consisting of a rolling diaphragm and check valves, is used as an experimental platform to validate the design strategy. Based on characterization data of both DEA membrane and pump, a systematic design approach based on graphical method is performed. The proposed design method allows to predict the system performance at high actuation frequencies by accounting for both static and dynamic effects, as well as external loads, without relying on complex material models. The design procedure forms the basis for building the pump by utilizing rapid prototyping. The performance of the pump can then experimentally evaluated in terms of pressure and resulting flow rate to validate the design concept.