Low-frequency vibration absorption of magnetic quasi-zero-stiffness structures with lever mechanism

Abstract

Dynamic vibration absorbers (DVAs) are widely employed in diverse engineering systems for their capacity to mitigate structural vibrations. However, traditional absorbers exhibit sensitivity to natural frequencies and present challenges in tuning within the low-frequency range. This study introduces a lever mechanism to enhance the low-frequency vibration absorption performance of magnetic quasi-zero-stiffness structures, resulting in a lever-type DVA (L-DVA). We elucidate the design philosophy behind the proposed L-DVA. An analytical model is derived based on the Lagrange equation and the frequency-response relationship is determined using the harmonic balance method. We conduct numerical and experimental analyses to assess the impact of the lever ratio, mass ratio, frequency ratio, nonlinear stiffness coefficient ratio, and damping ratio on vibration absorption performance. Furthermore, we fabricate a prototype of the L-DVA with an adjustable magnetic quasi-zero-stiffness structure, and the experimental results align with simulation outcomes. The result shows that this study is the ease of customization in the vibration absorption capabilities of magnetic quasi-zero-stiffness structures, achieved by adjusting the lever ratio. An increase in the lever ratio and tip mass effectively shifts the anti-resonant peak to a lower frequency. The decrease in the frequency ratio leads to a reduction in the anti-resonant frequency. This study validates the efficacy and feasibility of utilizing the L-DVA for low-frequency vibration absorption.