Analysis of Resonance Suppression Performance of a Time-Varying Isolation Platform

Expanding the low-frequency isolation range and suppressing the amplitude in the resonant region are important goals for vibration isolation in recent years. Various quasi-zero stiffness isolators and active isolators have emerged, achieving the expansion of the isolation range to low frequency. However, resonance suppression performance is limited by the damping structure and damping materials, making it difficult to achieve the ideal damping ratio. To simultaneously expand the low-frequency isolation range and suppress resonance, a time-varying isolation platform is proposed based on the resonant energy dispersion phenomenon of a time-varying structure. A finite element (FE) model of a fixed isolation platform is established to verify the low-frequency isolation range. One of the isolators slides along the flexible plate that changes the inherent characteristics of an isolation system which can suppress the formation of resonance. The effects of the time-varying path, damping and isolator stiffness on the amplitude in the resonant region are analyzed. The results demonstrate that the time-varying isolation platform not only has lower resonant frequency, but also can suppress the resonance peak to disperse the resonance energy in situations where system parameters are unidentified. The time-varying isolation platform provides a new approach for low frequency vibration isolation.