This paper studies the dynamic properties of a 3D chiral mechanical metamaterial, which largely depend on tacticity describing the connection forms of the chiral unit. Based on the finite element theory and Bloch's theorem, a dynamic model of the 3D chiral mechanical metamaterial is established to analyze the band structures and transmission responses. The isotactic configuration converts longitudinal waves into transverse waves due to the chirality, which results in the vibration attenuation of the longitudinal wave that is independent on band gaps. The band gaps appear at the band structures of the syndiotactic configuration, and the generation mechanism is related to the vibration mode of ligaments, which can be used to predict band gap. The samples were manufactured by additive manufacturing to vibration transmission test for verifying the dynamic responses and the band gaps of the 3D chiral mechanical metamaterial with different tacticities. In addition, the gradient design and programmable design are used to further expand the vibration attenuation region, which has the potential for practical applications of vibration suppression.

本文研究了 3D 手性机械超材料的动态特性，这在很大程度上取决于描述手性单元连接形式的立构规整度。基于有限元理论和布洛赫定理，建立了3D手性力学超材料的动力学模型，分析了能带结构和传输响应。等规构型由于手性将纵波转换为横波，这导致纵波的振动衰减与带隙无关。带隙出现在间规构型的能带结构上，其产生机制与韧带的振动方式有关，可用于预测带隙。样品通过增材制造进行振动传输测试，以验证具有不同立构规整度的 3D 手性机械超材料的动态响应和带隙。此外，采用梯度设计和可编程设计，进一步扩大了减振区域，具有抑振实际应用的潜力。