Study on the quasi-static and dynamic response of dielectric elastomer actuator under electrical loads

The characteristics of five strain energy functions for dielectric elastomer (DE) are compared. A hyperelastic constitutive model based on second order Ogden strain energy function is achieved, which can accurately simulate the nonlinear large deformation of VHB4910 DE membrane under different tensile rates. According to the established model of DE, the quasi-static and dynamic response equations have been developed with regard to the dielectric constant changes of DE. The relation between the element's pre-stretch and DC voltage under equal bi-axial loading condition is analysed. Its dynamic response is predicted under constant and harmonic electrical loads. The results show that DE has an optimal pre-stretch rate corresponding to a minimum DC voltage inducing its extreme electrodeformation. The electrical strength has a significant influence on the dynamic response of DE. The vibration frequency of DE actuator diminishes as the electrical strength increases. The variation behaves nonlinear.