Design and Experimental Study of a Quasi-Zero-Stiffness Vibration Isolator Based on the Spring Hinge Mechanism Metamaterial

Vibration has a great impact on the accuracy of precision instruments, so vibration isolation is essential. Quasi-zero-stiffness (QZS) vibration isolators are practical solutions for isolation in the low-frequency range. In this paper, a spring hinge mechanism metamaterial is proposed, which can adapt to varying load patterns while achieving a wide range of QZS, and the low-frequency and comprehensive-frequency vibration isolation performance is superior. This paper conducts static and dynamic analysis at the level of a single cell. Through static analysis, it can be found that the external force is always constant when the structural parameters meet the condition of QZS, which shows that the structure can achieve QZS in a large range of deformation. On this basis, the dynamic model is built, and the system response is simulated and analyzed under harmonic and sweep excitation. It is found that the vibration amplitude is almost zero in both cases, and the results show that the vibration isolation performance of the structure is superior. Furthermore, the spring hinge mechanism skeleton is obtained through 3D printing and an experimental testing setup is established. The experimental results demonstrate that the devised QZS isolator can achieve a wide range of QZS characteristics, and the vibration isolation effect of the structure is about 80% under random excitation. In the low frequency band less than 200 Hz, the transmission ratio of the system is less than 0.4, indicating that the devised spring hinge mechanism has superior vibration isolation performance of low frequency and comprehensive frequency.