标题： 面向制造的纠缠用于设计手性和各向异性超材料泡沫 显示英文标题

标题： Fabrication-Directed Entanglement for Designing Chiral and Anisotropic Metamaterial Foams

摘要： 纠缠网络在各种系统中至关重要，从生物结构到工程材料。 当前编程纠缠的技术通常依赖于复杂的化学反应，或者导致统计上均匀的网络，限制了创建具有精确工程功能的空间模式结构的能力。 因此，在单片纠缠结构内开发方法来编程复杂的机械行为（如各向异性和手性）仍然是一个关键挑战。 本文介绍了一种名为制造导向纠缠（FDE）的方法论，该方法结合了粘性线材打印（VTP）和拓扑优化（TO），用于编程单一均匀细丝的纠缠。 通过空间调整VTP参数（沉积高度、速度），我们控制局部卷曲密度，在单片纠缠泡沫中形成准两相（密集/稀疏）区域。 拓扑优化指导这些区域的放置，以实现目标宏观机械性能。 这里我们展示了具有可调柔韧性、刚度和手性的类似泡沫的机械超材料。 实验测试和模拟证实，与均匀VTP泡沫相比，FDE扩展了可实现的材料属性空间，使材料特性如可调方向刚度、泊松比从 $\nu\approx0.06~\text{to}~0.56$、以及由单一基础材料产生的新型显著正负耦合（$\eta_{212}\approx0.72$）成为可能。 这种方法为设计具有定制机械行为的复杂功能性纠缠泡沫结构提供了一个可行的新途径。 显示英文摘要

摘要： Entangled networks are fundamental in various systems, from biological structures to engineered materials. Current techniques for programming entanglement often rely on intricate chemistry or result in statistically homogeneous networks, limiting the ability to create spatially patterned structures with precisely engineered functions. Thus, a key challenge remains in developing approaches to program complex mechanical behaviors, such as anisotropy and chirality, within monolithic entangled structures. This work introduces Fabrication-Directed Entanglement (FDE), a methodology integrating viscous thread printing (VTP) and topology optimization (TO) to program the entanglement of a single homogeneous filament. By spatially adjusting VTP parameters (deposition height, speed), we control local coiling density, creating quasi-two-phase (dense/sparse) regions within a monolithic entangled foam. Topology optimization guides the placement of these regions to achieve target macroscopic mechanical properties. Here we show foam-like mechanical metamaterials with tunable compliance, rigidity, and chirality. Experimental testing and simulation confirm that FDE expands the achievable material property space compared to homogeneous VTP foams, enabling properties like tunable directional stiffness, Poisson's ratios from $\nu\approx0.06~\text{to}~0.56$, and novel significant normal-shear coupling ($\eta_{212}\approx0.72$) from a single base material. This approach offers a viable new pathway for designing complex, functional entangled foam structures with tailored mechanical behaviors.