Design and experimental study of a hybrid vibration absorber for global vibration control

A simple and practical hybrid vibration absorber (HVA) is proposed for global vibration control of flexible structures under random stationary excitations. The HVA, regulated by a pole placement controller, uses a linear translational feedback signal to synthesize active moment via a moment actuator. It is shown, analytically and experimentally, capable of damping vibration in the entire primary structure. While the passive tuned mass damper (TMD) can suppress tonal vibration in the primary structure at the vicinity of the coupling point, it enhances vibration at other locations and other frequencies. The presented HVA, in contrast, can provide more than 48% extra broadband attenuation on vibrations at multiple points when compared with the passive TMD in experimental verification on a beam structure. Up to 85% extra broadband attenuation can be observed at the coupling point. The proposed HVA is a simple and economic alternative for engineers to retrofit the conventional TMD to a higher performance HVA for damping vibrations at multiple locations of the primary structure.