Multi-mode reduction of structure by viscoelastic material containing embedded ball-like mass

The authors have been studying a multimodal and multiaxial vibration reduction device called eMDVA (embedded Mass Dynamic Vibration Absorber) which consists of a spherical shaped mass embedded in viscoelastic material. In a recent paper, we developed an FEM model based on experimental results of the eMDVA with spherical viscoelastic material and used it to design ellipsoid-shaped viscoelastic material. This paper presents an experimental investigation of the multiaxial vibration reduction ability of the eMDVA and compare the experimental result with the numerical ones by the FEM model. An eMDVA with ellipsoid-shaped viscoelastic material designed by the FEM model was constructed and its vibration characteristics were measured. Then, a series of vibration measurement tests for a 1:10 scale model of the underframe of a railway vehicle by applying the eMDVA has been conducted and the multi-mode vibration reduction effect has been confirmed.