Semi-active vibration absorber based on real-time controlled MR damper

• A new semi-active vibration absorber with real-time controlled MR damper (MR-SVA) is developed.
• The frequency control takes the semi-active restriction of the MR damper force into account in order to guarantee precise frequency tuning of the MR-SVA.
• The non-linear adaptive damping control takes the limited stroke of the MR-SVA mass into account to secure that the MR-SVA can be installed on real structures where space is limited.
• The experiments show that the MR-SVA outperforms the passive TMD significantly in all test cases.

A semi-active vibration absorber with real-time controlled magnetorheological damper (MR-SVA) for the mitigation of harmonic structural vibrations is presented. The MR damper force targets to realize the frequency and damping adaptations to the actual structural frequency according to the principle of the undamped vibration absorber. The relative motion constraint of the MR-SVA is taken into account by an adaptive nonlinear control of the internal damping of the MR-SVA. The MR-SVA is numerically and experimentally validated for harmonic excitation of the primary structure when the natural frequency of the passive mass spring system of the MR-SVA is correctly tuned to the targeted structural resonance frequency and when de-tuning is present. The results demonstrate that the MR-SVA outperforms the passive TMD at structural resonance frequency by at least 12.4% and up to 60.0%.