Structural vibration control using a tunable hybrid shape memory material vibration absorber

摘要

Vibration absorber has been used as an effective tool in the vibration reduction of structure-suffered single-frequency excitation. However, for structures subjected to excitation with varying frequency, an absorber with actively tunable fre quency capability may offer more powerful solution. In this study, an absorber that consisted of a spring element made of hybrid shape memory materials was proposed. A cantilevered beam fabricated by superelastic core and shape mem ory polymer sleeves was employed as the spring element of the absorber. By controlling the electric current through the superelastic core, and thereby the temperature of the shape memory polymer sleeves, the natural frequency of the absorber was tunable. The fabricated hybrid shape memory material absorber was capable of changing its natural fre quency by more than 45%. Finally, vibration reduction of a cantilever structure subjected to different harmonic excita tions was demonstrated using gain-scheduling control algorithm.