新型准零刚度系统的设计、分析与仿真

DESIGN,ANALYSIS AND SIMULATION OF A NOVEL QUASI-ZERO STIFFNESS VIBRATION ISOLATION SYSTEM

采用拉伸弹簧组成的负刚度机构与正刚度线性弹簧并联,设计出一种新型的拉伸式准零刚度隔振系统,可用于隔离低频或超低频振动。建立该系统的静力学模型,得到系统具有准零刚度特性时所需满足的条件;与一种压缩式隔振系统的力-位移曲线进行对比;分析垂向弹簧的调节对系统的影响;建立该系统在简谐位移激励下的非线性动力学方程,利用谐波平衡法求得系统的近似响应;与压缩式隔振系统的位移传递率曲线进行对比;探索系统各主要参数对响应的影响;建立Adams动力学模型,通过仿真结果来证明静力学模型的正确性,并模拟基座激励振动,证明了拉伸式准零刚度系统在低频或超低频隔振中的性能远优于线性系统。

Combining a negative stiffness mechanism composed of tension spring with a linear positive stiffness spring in parallel,a novel quasi-zero stiffness vibration isolation systemwas designed which can be used to isolate low or ultra-low vibration. The static model of the system was established and the condition of quasi-zero stiffness characteristics was obtained.The fore-displacement curves of the tension-type isolator and a compression-type isolator were compared. The effect of adjustment of vertical spring in the system was analyzed. The dynamic equation was established when the system was excited by a harmonic amplitude on the displacement and the equation was solved by using Harmonic Balance method. The displacement transmissibility curves of the tension-type and the compression-type isolators were also compared. The effect of the main parameters on response of the system was explored. ADAMS model was established and the static model was proved to be correct. The vibration simulation results prove that the quasi-zero stiffness system has greater advantage than linear system in low or ultra-low vibration isolation.