Pinnacle elimination and stability analyses in nonlinear oscillation of soft dielectric elastomer slide actuators

Dielectric elastomers (DEs) exhibit significant potential applications as soft robots. Due to complicated electromechanical coupling behavior, DEs generate a strong nonlinear oscillation, which may induce the undesired failure and other instabilities. Based on the DE slide actuators (DESAs), we deduce a viscoelastic dynamic model by incorporating the inertial forces and viscous dampings in all three principal directions. Numerically, calculations are utilized to detect the dynamic properties of the DESA. By employing the established model, the special phenomenon of pinnacle elimination in nonlinear oscillation is achieved. The dynamic loss of tension instability in both two DE membranes of the DESA is also analyzed. Effects of the voltage amplitude, the mass bar, the length ratio between two membranes, and the prestretches of DEs are considered and discussed, respectively.