Investigation on the dynamic performance of viscoelastic dielectric elastomer oscillators considering nonlinear material viscosity

As a typical kind of soft electroactive materials, dielectric elastomers are capable of producing large deformation under external stimuli, which makes them desirable materials for many practical applications in transduction technology, including tunable oscillators and resonators. The dynamic performance of such dielectric elastomer–based vibrational devices is strongly affected by material viscosity as well as electromechanical coupling. Moreover, as suggested by experiments and theoretical studies, dielectric elastomers exhibit deformation-dependent relaxation process, which makes the modeling of the dynamic performance of dielectric elastomer–based devices more challenging. In this work, by adopting the state-of-art modeling framework of finite-deformation viscoelasticity, the effect of the nonlinear material viscosity on the in-plane oscillation and the frequency tuning of dielectric elastomer membrane oscillators is investigated. From the simulation results, it is found that the nonlinear viscosity only affects the transient state of the frequency tuning process. The modeling framework developed in this work is expected to provide useful guidelines for predicting the dynamic performance of dielectric elastomer–based vibrational devices as well as their optimal design.