A Review on High-Frequency Dielectric Elastomer Actuators: Materials, Dynamics, and Applications

Dielectric elastomer actuators (DEAs) as a typical class of electroactive polymers have been developed rapidly in the last two decades due to their advantages such as large strain, high energy density, and fast response. The high-frequency characteristics of DEAs enable them to be applied in a wider range of fields. In this review, the high-frequency (>10 Hz) characteristics and applications of DEAs are focused on. The basic concepts and metrics for high-frequency DEAs are first given. Next, the commercial and synthesized dielectric and electrode materials of DEAs used in high-frequency applications are reviewed. Following materials, strategies for extending the lifetime of DEAs are introduced. Subsequently, the dynamic modeling approaches for DEAs are presented, considering damping, inertia, and the electrical loss. Building on the fundamental research, some important applications are summarized based on the high-frequency motions of DEAs including loudspeakers, active vibration suppression, pumps/valves, haptic devices, and high-speed mobile robots. Finally, the conclusions and future perspectives are given. This review will give readers a clearer understanding of how to design and use high-frequency DEAs.