含有时滞控制的准零刚度隔振器动力学分析

A quasi zero stiffness (QZS) vibration isolator can be realized through parallel connection of a positive stiffness and a negative one. Here, the dynamic features of a QZS vibration isolator composed of two oblique springs and a vertical spring under the simple harmonic excitation were studied. Introducing the linear displacement time-delay control strategy, the dynamic response characteristics of the system under the simple harmonic excitation were obtained with the averaging method. The first-order Lyapunov approximate stability theory and Routh-Hurwitz criterion were adopted to analyze the stability, jump phenomenon and Hopf bifurcation of the controlled system. The results showed that the time-delay control strategy can effectively improve the stability of the QZS vibration isolator; jump phenomenon and Hopf bifurcation can be avoided through choosing appropriate control parameters.