Study on the hydraulic leveraged dynamic anti-resonance vibration isolator with nonlinear damping characteristics

The hydraulic leveraged dynamic anti-resonance vibration isolator with nonlinear damping characteristics are analyzed under harmonic excitations. A nonlinear mathematical model is proposed considering both the nonlinear damping of the fluid resistance and the volumetric stiffness induced by the bulge effect. The harmonic balance method, combined with the arc-length continuation algorithm, is performed to investigate the steady-state response and vibration transmissibility quantitively. The optimization of isolator parameters are obtained using the fixed-point theory, which leads to the relation between the damping coefficients and isolation performance. Parametric studies are then carried out to investigate the effects of the volumetric stiffness, bellows stiffness, and lever ratio on the isolation performance. The results indicate the importance of the damping parameters on the design of the band-stop characteristics to achieve the anticipated performance of anti-resonance isolators. Furthermore, the inertia-amplification ratio of the anti-resonance isolator needs to be balanced against its stopband suppression performance for the fluid-type leveraged system.