Adaptive Tuned Dynamic Vibration Absorber With Variable Stiffness Property Using Magneto-Rheological Elastomers

A passive type dynamic vibration absorber offers advantages in reliability and simple constitution, however, the use of the absorber with fixed property is usually limited to harmonically excited case, where the damper is only effective for pre-determined narrow frequency range. Design of the damper following well-known optimal tuning theory could extend the effective frequency range, yet the damping performance remains at a certain amount. In this paper, the stiffness controllable elastomer composite known as Magnetorheological elastomer (MRE) is applied to the dynamic absorber whose natural frequency is tunable by the external magnetic field. MREs are first fabricated and their field-dependent properties are investigated. The MRE is then applied to a dynamic absorber along with stiffness switching scheme so that the vibration of 1-DOF structure is damped more effectively. Investigations show that the vibration of the structure can be fully reduced by the proposed dynamic absorber with variable stiffness functionality.