介电弹性体驱动器动态电压下的变形特征及击穿行为研究

Dielectric elastomer based actuators (DEAs) is regularly subjected to dynamic electric loads to produce reciprocating deformations and its driving performance such as deformation response and breakdown behavior is affected by various driving voltage parameters. The relevant changing laws are unrevealed, and it is difficult to predict its critical breakdown condition in applications. The dynamic deformation and breakdown behaviors of circular DEAs based on VHB4910 film are experimentally investigated, and the changing rules of driving voltage parameters on the dynamic deformation and breakdown behavior of DEA are summarized. The experimental results show that the dynamic deformation equilibrium positions of the DEAs are affected by the voltage amplitude and the deformation amplitudes are influenced by both the frequency and amplitude of the voltage. Moreover the dynamic breakdown voltages of DEAs appear to be scattered with no obvious regularity, while the dynamic voltage cycle index of DEAs is significantly affected by driving voltage parameters. Finally, the classical fatigue curve equation under the mechanical cycle loads is referred to propose a formula that is used to characterize the electric fatigue curve of DEA by replacing the mechanical stress amplitude with the nominal electrostatic stress. This study provides a new way for predicting the dynamic voltage cycle index of DEA under dynamic voltages.