Design and simulation analysis of a quasi-zero stiffness flexible vibration isolation metastructure

Abstract

To effectively suppress the low-frequency micro-vibration, a multilayer quasi-zero stiffness flexible vibration isolation metastructure is proposed in this paper. First, a single-layer quasi-zero stiffness flexible structure is designed based on the compliant mechanism theory by using the shape optimization method. Second, based on the large deformation theory combined with the shooting method, the static characteristics of the flexible structure are analyzed and later verified by the finite element simulation. Finally, the single-layer vibration isolation structures are stacked to construct a multilayer quasi-zero stiffness flexible vibration isolation system, whose finite element model and multi-degree-of-freedom simplified model are established, and their vibration isolation characteristics are studied. Moreover, the effects of the damping ratio and the number of layers on the vibration isolation performance are discussed. The results indicate that in the frequency range of effective vibration isolation, with the increasing number of layers, the initial vibration isolation frequency shifts toward a low frequency, and the vibration isolation effect is markedly improved.