A high-performance dielectric elastomer actuator with programmable actuations

Abstract

The rapid development of the soft robotics has led to the emergence of many novel soft actuators, among them, dielectric elastomer actuators (DEAs) have demonstrated the clear advantages of large actuation strains, fast response speeds and high energy densities. When actuated at its resonance, the DEA can exhibit a significantly boost in its output stroke/power and energy efficiency, thus enabling dynamic soft robotic applications with high power density demands. As a result, increasing researches have been dedicated to improve the outputs of the DEAs and to expand their functionalities. In this work, we present a bistable DEA (BDEA) that exploits the inherent bistability to broaden the resonant bandwidth, increase the output and expand the actuation programmability. Through extensive experiments, we show that proposed BDEA can exhibit a significantly broader resonant bandwidth and potentially higher power output and energy efficiency than a monostable counterpart that is widely adopted in the literature. The developed BDEA also exhibits three oscillation modes and a control strategy is proposed to achieve switching between these oscillation modes. Robust programmable actuation is demonstrated in experiments in this work. The outcomes of this work can offer guidelines for developing next-generation highly programmable DEAs and multi-functional soft robotic systems.