Isolating vibrations with different polarizations via lightweight embedded metastructure

Lightweight engineering structures often suffer from environmental vibration that is difficult to suppress due to its low frequency and multiple polarizations. The emerging field of metastructure offers a practical solution for the lowfrequency vibration reduction without introducing extra isolators that have gigantic size and heavy weight. In this research, 3D printed subwavelength-scale microstructures are embedded into a honeycomb structure to form a lightweight metastructure which can suppress vibrations with different polarizations at targeted frequencies. Moreover, by simply rotating the fabricated resonators from horizontal embedment into vertical embedment, the bandgaps as well as the vibration isolations can be easily switched for different vibration sources. The multi-polarization vibration suspensions have also been demonstrated with strategically positioned resonators following interval and segment arrangements. Finally, metastructures with quasi-zero dynamic stiffness are designed to achieve the ultra-low frequency vibration isolation while maintaining their lightweight.