부산대학교 도서관

The effect of the Coulomb friction on a quasi-zero stiffness (QZS) isolator which configured by combining an Euler buckled beam negative stiffness corrector and a linear isolator is presented in this paper. Assuming friction damping provided by linear roller guider, the dynamic responses of the vibration isolation system and the equivalent linear one are obtained by using harmonic balance method (HBM). The static and dynamic characteristics of the QZS isolator are both investigated. For the linear isolator, the resonance frequency will increase and the peak transmissibility will decrease with the increasing of Coulomb friction or the decreasing of the excitation amplitude. However, in the case of QZS isolator, the natural frequency is decreased with the help of the negative stiffness mechanism and the amplification factor at the resonance is not obvious with the presence of the friction damping. Theory and experiment show good accordance. Therefore, it is recommend that one should add light Coulomb friction damping into the system to get better performance when using the QZS isolator in practice. The results present here can be a useful guideline when design such kind of vibration isolator.