In this paper, chiral metamaterials (CMM) were optimized from conceptual design to fine design with the effective elastic constants unchanged under finite strain. First, through calculation and comparison of examples, the unit cell method was selected to compute the effective elastic properties of the periodic chiral metamaterials under finite strain. Secondly, the conceptual design of chiral metamaterials with prescribed Poisson’s ratios under finite strain was realized through density-based and feature-driven topology optimization. Then, the method of moving asymptotes (MMA) was used to solve the optimization problems. Based on the optimal configuration, chiral metamaterials with prescribed Poisson’s ratios and Young’s moduli under finite strain were carefully designed through shape optimization. Genetic algorithm was used to solve the optimization problem. Finally, the optimal models were fabricated by 3D printing. The optimal design was validated by tensile test results, i.e., the designed chiral metamaterials can maintain effective elastic properties under large deformation, and the invariance of the effective elastic properties depends on the nonlinearity of the flexible chiral metamaterials.

本文从概念设计到精细设计优化了手性超材料（CMM），在有限应变下有效弹性常数不变。首先，通过实例的计算和比较，选择了晶胞方法来计算周期性手性超材料在有限应变下的有效弹性。其次，通过基于密度和特征驱动的拓扑优化，实现了在规定应变下具有规定泊松比的手性超材料的概念设计。然后，使用移动渐近线（MMA）的方法来解决优化问题。根据最佳构型，通过形状优化，精心设计了具有规定泊松比和杨氏模量的手性超材料。用遗传算法解决了优化问题。最后，通过3D打印制作了最佳模型。拉伸试验结果验证了最佳设计，即所设计的手性超材料可以在大变形下保持有效的弹性，而有效弹性的不变性则取决于柔性手性超材料的非线性。