Abstract：A compact ball-type quasi-zero-stiffness (QZS) isolator was proposed for the low-frequency vibration isolation. Firstly, parameters of quasi-zero stiffness were obtained by static analysis. Furthermore, dynamic model of the isolation system was established, and the frequency-response characteristic and vibration isolation performance were analyzed by using harmonic balance method. Effects of excitation amplitude and damping on the response were also discussed. Finally, numerical simulations were carried out by ADAMS software, and vibration isolation efficiencies were evaluated. Compared with the corresponding linear vibration isolation system, the QZS vibration isolator can obviously reduce the starting vibration isolation frequency, and posses much lower transmissibility in the range of low frequency. Therefore, negative stiffness resulting from ball-type mechanism significantly reduces the total vertical stiffness of the system, and the excellent low-frequency vibration isolation performance is achieved. What’s more, the compact design can be easy implemented for engineering practice.
2015, Vol. 34 
