A study of a beam-like electromagnetic vibration absorber

This paper presents a study of a beam-like semi-active electromagnetic vibration absorber (EVA). The EVA consists of a flexible ferromagnetic cantilever beam, a ferromagnetic mass attached to the free end of the beam, and an E-shaped electromagnet. By changing the current of the electromagnet, the interactive force between the ferromagnetic mass and the electromagnet is varied accordingly, hence, the stiffness of this EVA is online tunable. The working frequency of the EVA is adjusted simultaneously as well. A finite element method (FEM) analysis study has been carried out to determine the characterization of the EVA. The effective stiffness of the absorber from FEM agrees with the results from the experiment well. A 2 degree-of-freedom experimental semi-active control system is built up to test the effectiveness of the EVA design. The performance under both steady-state exciting and sweeping frequency exciting show the EVA effectiveness in vibration suppression.