Characterization of an Electromagnetic Vibration Isolator

Naibiao Zhou, Kefu Liu

.

DOI: 10.4236/jemaa.2011.312079                

Abstract

A novel vibration isolator is constructed by connecting a mechanical spring in parallel with a magnetic spring in order to achieve the property of high-static-low-dynamic stiffness (HSLDS). The HSLDS property of the isolator can be tuned off-line or on-line. This study focuses on the characterization of the isolator using a finite element based package. Firstly using the single physics solver, the stiffness behaviours of the mechanical and magnetic springs are determined, respectively. Then using the weakly coupled multi-physics method, the stiffness behaviours of the passive isolator and the semi-active isolator are investigated, respectively. With the found stiffness models, a nonlinear differential equation governing the dynamics of the isolator is solved using the time-dependent solver. The displacement transmissibility ratios of the isolator are obtained. The study confirms that the isolation region of the isolator can be widened through off-line or on-line tuning.

Keywords

High-Static-Low-Dynamic Stiffness Spring, Semi-Active Vibration Isolator, Magnetic Spring, Coupling of Structural Mechanics and Magnetics

Conflicts of Interest

The authors declare no conflicts of interest.

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