Dynamic characteristics analysis for a quasi-zero-stiffness system coupled with mechanical disturbance

Abstract

In this paper, an analysis is given about dynamic characteristics for a quasi-zero-stiffness isolator coupled with mechanical disturbance from a view of engineering application. In addition to traditional Columbo friction and linear damping in the vertical direction, the influence of other disturbing parameters such as geometrically nonlinear damping, friction and inertia of rods is also taken into consideration. The dynamic equation is formulated with parameters above to give an investigation of static characteristics, respectively, based on Newton’s second law and D’Alembert’s principle. Moreover, the frequency–amplitude response and transmissibility characteristics are obtained for this model subjected to the vibrating base by using average method with the introduction of piecewise function and then analyze the effect on the vibration response and isolation caused by disturbance. Furthermore, the passive vibration isolation simulation is conducted to verify the theorem. Therefore, it is recommended that the geometrically nonlinear damping can be introduced to the quasi-zero-stiffness system appropriately which can decrease the peak value of transmissibility in the low-frequency range, and nearly has no effect on the high-frequency region. And the mass of the rod should not be bigger than $$10^{-3}$$ times of the isolator. The conclusions can provide engineering guidance for design and application about quasi-zero-stiffness system.