Bioinspired bistable dielectric elastomer actuator based on low-melting-point alloy phase change regulation

Soft bistable actuators that exhibit flexibility, fast response, and low energy consumption are key components for applications such as fast grippers, shape reconfiguration actuators, and deployable soft robots. Inspired by the structure of rhododendron leaves, we designed a bistable dielectric elastomer actuator (BDEA) by integrating a dielectric elastomer with a low-melting-point alloy. The developed BDEA can operate reversibly between two stable states through the synergistic application and control of high voltage and Joule heating. The transition process between the two stable states of the actuator was elucidated using finite element analysis. The bending angles of the actuator in the two deformation directions were measured, and grasping experiments were performed. The experimental results show that the direction and magnitude of deformation of the bistable actuator can be tuned to conform to the shape of the target object. The developed BDEA has enhanced shape adaptability and higher bearing capacity compared to conventional soft actuators.