A Novel Electromagnetic Quasi-zero Stiffness Vibration Isolator: Non-contact Design and Performance Evaluation

This study presents a novel non-contact electromagnetic quasi-zero stiffness (QZS) vibration isolator designed to address the limited low-frequency isolation performance of conventional linear isolators, as well as the inherent issues of friction, wear, and fatigue in traditional QZS systems. The proposed isolator integrates a negative stiffness mechanism — formed by bilateral linear eddy current stators and ferromagnetic plates — in parallel with a positive stiffness unit comprising disc-type eddy current stators and a permanent magnet array. This hybrid configuration enables QZS characteristics near the equilibrium position, thereby achieving effective low-frequency vibration isolation. Both electromagnetic simulations and experimental results confirm that the non-contact operation eliminates mechanical wear, significantly enhances system reliability, and provides high redundancy by maintaining operational functionality even under partial coil failure. Furthermore, by tuning the excitation current, the system achieves adaptive wideband isolation across varying load conditions. The proposed design not only substantially improves low-frequency isolation performance but also maintains a high load-carrying capacity, offering a robust and reliable solution for practical low-frequency vibration.