An adaptive control system for dielectric elastomers

Dielectric elastomers actuate under a capacitive mechanism and the resulting actuator is especially desirable as a biomimetic 'artificial muscle' device. This paper investigates the development and control of an acrylic dielectric elastomer, 3M VHB 4930, when used as a mechanical actuator. An embedded sensing and actuation system is proposed in the paper. The capacitance of the dielectric elastomer would be calculated using the feedback of a high frequency sensing signal attached to the actuation voltage. A PID closed loop quasi-digital voltage control system is developed for controlling the actuation voltage. Experiments are carried out to test the performance against the nonlinearity of the material. The combination of the solutions proved the feasibility of using the dielectric elastomer as a mechanical actuator.