Design of Facile Dielectric Elastomer-Based Bending Module for Soft Robotics Applications

Abstract

Abstract Dielectric elastomer (DE)-based soft actuators have been actively studied in the field of soft actuation technology based on their unique properties such as high energy density, large actuation strain, inherent compliance, lightweight, silent operation, and faster response when compared with other actuators. A dielectric elastomer actuator (DEA) bending module based on dielectric elastomer minimum energy structures (DEMES) is proposed by adopting a bi-material system consisting of a DE membrane attached to a flexible acrylic frame with a hollow in the middle. Its bending performance can be satisfactorily predicted analytically and numerically, which helps design the DEA bending module better. For a typical DEA bending module with a DE membrane of 20 mm × 20 mm (width and length) and an acrylic frame with a hollow of 4 mm × 60 mm (width and length), 30.23° actuation angle and 53.96° actuation angle can be achieved with a single module and two serially assembled modules, respectively, under an 8 kV excitation voltage. The hollow design on the acrylic frame avoids the contact problem between the electrode-coated DE layer and the stiff frame sheet. A soft rotatable gripper and a biomimetic crawling robot are designed and fabricated for demonstration.