X型准零刚度隔振器的隔振特性分析

将一种X型结构应用于准零刚度隔振器以改善其低频隔振性能.根据牛顿运动定律建立了系统的动力学方程.利用增量谐波平衡法对非线性常微分方程进行求解，得到系统的幅频响应曲线.讨论了等同约化刚度γ值对系统传递率的影响.研究结果表明:水平弹簧的无量纲预压缩长度的合理区间为 (0，2).在共振区时，γ值的增大可以减小力传递率.在较高频率激励下，γ值的变化对系统隔振性能影响较弱.随着γ值减小，共振区的位移传递率急剧减小.此外，γ值的减小也会引起共振频率减小，并且使得跳跃现象消失.因此，X型准零刚度隔振器的等同约化刚度γ值是一个可以有效反映系统低频隔振效果的理想参数.

Vibration Isolation Characteristics Analysis of X-shaped Quasi-Zero Stiffness Vibration Isolator

An X-shaped structure is applied to quasi-zero stiffness isolator to improve its low frequency isolation performance. The dynamic equation of the system is established by using the Newton’s motion law. The amplitude-frequency response curves of the system are obtained by using the incremental harmonic balance method. The effect of equivalent reduced stiffness γ on system transmissibility is discussed. Research results show that the reasonable numerical interval of dimensionless pre-compression length of horizontal spring is (0， 2). In the resonant region， the increase of γ can significantly reduce the force transmissibility. At higher excitation frequencies， the effect of the change of γ on the vibration isolation performance of the system is weak. With the decrease of γ， the displacement transmissibility in the resonance region decreases sharply. In addition， the decrease of γ will also reduce the resonance frequency and make the jump phenomenon disappear. Therefore， the equivalent reduced stiffness γ of the X-shaped quasi-zero stiffness isolator is an ideal parameter which can effectively reflect the effect of low-frequency vibration isolation of the system. The effect of equivalent reduced stiffness γ is discussed in detail.