High-Performance Dielectric Elastomer Actuators

Abstract

Dielectric elastomer actuators (DEAs) feature high energy efficiency, lightweight, design flexibility and the use of low cost materials and processes. This holds particularly true for membrane actuators, which, in addition to the dielectric elastomer comprise a separate biasing system. The particular design of the biasing system may dramatically improve the DEA performance, but at the same time, it adds complexity to such a design process. Therefore, in this work, a systematic design approach to adapt DEA systems to specific applications is developed. It allows calculation of all relevant design parameters and incorporates experimentally validated scaling laws to account for actuator geometry \neffects. Finally, the capability of the design process is illustrated at two examples. In the first one, the force output of circular membrane DEAs, which is typically in the hundreds of millinewton range, is increased by more than two orders of magnitude. For the first time, record-high forces of 100 Newton are generated, while an innovative overall system design maintains compactness. The second system is designed for high reversible actuation strains in the range of >50%. The use of silicone as elastomer additionally results in high-speed actuation. DEA systems with such outstanding performance prove that they are capable of competing with existing technologies such as solenoids, while adding additional functionality and, in the future, smartness through “self-sensing” properties.