This work presents and demonstrates a passive isolation system that offers the performance of a skyhook damper, but without the need of an inertial reference. This “virtual skyhook” isolation system can be used to reduce the transmission of base excitations to a structure. An analysis of the concept is presented, and model predictions are compared to experimental measurements for a simple test structure. The results demonstrate that the proposed isolation system significantly attenuates transmissibility at resonance without the penalty of increased transmissibility at higher frequencies, which often limits the performance of passive approaches. Practical issues regarding the design and implementation of the virtual skyhook vibration isolation system are also presented and discussed. To the best of the authors’ knowledge, this is the first experimental demonstration of an entirely passive skyhook damper isolation system.

Issue Section:
Technical Papers
Keywords:
resonance, damping, vibration isolation
Topics:
Dampers, Damping, Design, Resonance, Springs, Vibration isolation, Excitation
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 by ASME
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