Effect of Tacticity on the Dynamic Response of Chiral Mechanical Metamaterials

In this work, a tacticity strategy is proposed to adjust the mechanical properties of chiral mechanical metamaterials for vibration isolation. By applying the finite element method, the impact of tacticity on tensile deformations, band structures, and vibration transmission spectra of chiral metamaterials is investigated. The axial deformations of isotactic configuration and syndiotactic configuration are similar under tensile loads, but rotational deformation occurs in the isotactic configuration. With the same geometric and material parameters, the first band gap of the syndiotactic configuration is lower than that of the isotactic configuration. The vibration suppression performance of chiral mechanical metamaterials is verified by numerical simulations and experiments. Parametric analysis of the band gap provides valuable insights for the manipulation and expansion of vibration reduction. Gradient design based on parametric analysis achieves an extended range of vibration suppression.