Characterization of the transverse elongation of polymeric electrostatic actuators induced by Maxwell stress

This article gives a review of the research done in our lab over the past few years on the characterization of the transverse elongation of polymeric electrostatic actuators induced by Maxwell stress. Dielectric elastomers are known to produce large transverse strains in response to Maxwell stresses and thus provide a useful form of electromechanical actuation. The transverse strain responses of dielectric elastomer based Maxwell stress actuators have been investigated. The mechanical properties of elastomer cannot be fully understood on the basis of linear elastic theories. Models of hyperelasticity that are capable of describing the large deformation of rubber-like polymer materials have been used to interpret our experimental results. Our experimental and FEA studies on elastomer film actuators have helped us to understand how both the geometry and the material properties of the elastomers influence the observed actuation capabilities. Getting a high transverse strain requires not only good material properties, but also optimized actuator/electrode geometry. Some other factors, such as the electrode properties also influence the actuator performance.