Vibration investigation of conical dielectric elastomer thin membrane for energy harvesting system

Abstract

• Vibration model of conical DE membrane considering the rotation is established. • Experiment test is carried to validate output voltage of this conical membrane. • Effects of geometric size of the structure on vibration characters are studied. The dielectric elastomer (DE) has promising application prospects in many fields such as biomedicine, human-machine interface, soft robots, and energy harvesting. In present study, the conical energy harvesting structure is investigated and the DE is viewed as the hyperelastic neo-Hookean model. Considering the rotation and the tension of the DE membrane, the dynamic model of the conical DE thin membrane, i.e. mass-spring system is established based on the Euler-Lagrange method. The experiment is carried out to validate the output voltage of the conical thin membrane. The effects of excitation frequency, geometry size of the conical DE membrane, stiffness of the spring, pre-stretching on the resonance frequency, displacement amplitude and failed region are fully studied. The results demonstrate that the geometric size of the conical DE membrane greatly affects the resonance frequency and the amplitude. The principal resonance frequency of the quasi pointed conical DE structure is greater than the frustum conical DE structure, and the principal frequency of the quasi cylindrical conical DE structure is the lowest. The experiment result fits very well with the theoretical result for the output voltage. These findings can provide beneficial guidance for the design of the energy harvesting structures of high efficiency.