  We investigate the ture electromechanical stability of dielectric elastomer
actuators by considering the competition between Maxwell and mechanical
stresses. Existing researches based on the positive defiiteness of the nominal
Hessian matrix addressed only the initial load routie stability, i.e., Born
stability, in the absence of prestresses. We generalize this method to account
for electromechanical stability at any prestress state. For large enough
prestresses, we demonstatre that the previous method for Born stability may
lead to predcitions that deviate considerably from the true results. The true
method for electromechanical stablity can help the factual design of actuators
constructed from dielectric elastomers.
