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Wound roll Electroactive polymer actuators fabricated with Dielectric Elastomer (DE) materials provide high bandwidth actuation for robots, minipumps, loudspeakers, valves and prosthetic devices. In this paper we develop a DE wound roll actuator fabrication process that produces high strain (13%), reliable (3480 cycles at maximum strain), and stiff (157 N/m) actuators. An axisymmetric Finite Element Method (FEM) model with electrostatic and radial bulk modulus nonlinearity predicts actuator displacement and stress. The maximum compressive radial stress occurs at the center of the innermost active layer. This layer also has the thinnest material, indicating the most likely failure point. The nonlinear model predicts actuator displacement in response to applied voltage and load, and matches experiments to within 1 mm 1

In this paper a simple experimental system consisting of a length of cable, fixed to the edge of a rotating disc at its upper end, and free at its lower end or with a point mass ( drogue ) attached there, is described. This system exhibits a rich variety of bifurcation behaviours as the length of cable, angular speed of the fixed end, mass of the drogue and elasticity of the cable is varied. Bifurcation diagrams for the quasistationary configurations (cable shapes that appear stationary with respect to the rotating reference frame) are described. Linearized stability analyses of these quasistationary balloons are compared with solutions to the full time–dependent equations of motion. It is shown that there is an exchange of stability at the turning points of the quasi–stationary bifurcation curves, and that Hopf bifurcations occur at otherwise undistinguished points of these curves. It is shown that limit–cycle oscillations of the system occur at angular speeds corresponding to points on the bifurcations curves in the neighbourhood of the Hopf bifurcation points. These oscillations have been observed experimentally.