A low-frequency vibration isolator using permanent magnets and Kresling origami structure

The performance deterioration behavior resulting from vibrations in various mechanical systems, such as precision instruments, has long plagued engineers. One efficient approach for vibration protection is to use a quasi-zero stiffness (QZS) structure, which has high static and low dynamic characteristics. In this study, a low-frequency vibration isolator using permanent magnets and a Kresling origami structure is proposed that works for both torsional and/or axial excitations. The responses to both deterministic and random excitations were studied by establishing dynamic equations. The results show that the coupling of the axial and torsional motions results in an additional mass, which reduces the frequency and improves the low-frequency performance of the QZS structure. Force transmissibility was used to demonstrate the effects of the QZS structure. Compared with the degenerated linear system, the force transmissibility was lower over a wider frequency range. The ratio of the mean–square force of the QZS structure to that of a degenerate linear system under random excitation was also investigated. For weak Gaussian white noise, the QZS structure is effective and suitable for varying frequencies. However, it does not work for strong excitations. The results also show that the system damping aids in vibration isolation. We believe that our work provides a new method for designing a QZS structure using origami structures for multidirectional excitations.