EFRI NewLAW: Topological Mechanical Metamaterials Science

工程、物理和材料科学中的重大挑战之一是设计具有自然系统中不存在的特性的材料的能力。机械超材料试图通过建立一个由线性或非线性组件组成的聚合系统来实现这一点，这些组件共同展示了不同于其组成材料的材料特性和功能，甚至超过了它们的组成材料的特性和功能。然而，它们的功能通常会受到缺陷和缺陷的影响，这在现实世界的应用程序中是不可避免的。这就引出了一个问题，即是否存在一种新的范式，由此一种新的构建块和相互作用类别使材料的设计能够对缺陷坚固，并以新的功能为特征。这些研究将证明，拓扑学中的概念提供了一种组织原理，该原理在波导、结构稳定性和断裂等领域引起了广泛的杂质免疫现象。该项目的发现将对机械能控制系统和设备的设计和制造产生影响，这些系统和设备的运行依赖于波的聚焦、放大、定位和衰减。其中包括超声波换能器、声纳、噪音吸收或增强装置，以及用于振动过滤和冲击/爆炸保护的材料系统。该项目的目标将通过一个团队的合作实现，该团队汇集了拓扑机械超材料、实验波动力学、线性和非线性波传播、凝聚态物理和数学方面的专家。这种多学科的研究方法提供了大量机会，扩大工程和科学领域代表性不足群体的参与范围。例如，将与芝加哥科学与工业博物馆合作，组织面向代表性不足群体的外联计划。这个项目研究了挑战力学中经典概念的拓扑力学超材料，如互易性、时间反转对称性和对缺陷的敏感性。我们的目标是研究它们的基本性质，如有序、无序和非晶态系统中拓扑模的存在，非线性的影响，以及整体的能量输运。在这些研究的指导下，研究小组将探索拓扑机械超材料的工程意义，重点是波导性、结构稳定性和断裂。这些研究将在新的实验平台上进行，从陀螺系统作为概念验证，到新设计的具有材料/结构系统开发潜力的连续系统。这项研究有望实现改变动态控制设备和材料设计范式的功能。该团队在理论、模拟和实验方面的独特优势提供了成功执行这一雄心勃勃的研究计划所必需的技能组合。

One of the grand challenges in engineering, physics, and materials science is the ability to design materials with properties that do not occur in natural systems. Mechanical metamaterials attempt to achieve this by building an aggregate system out of linear or nonlinear components, that collectively exhibit material properties and functionalities that differ from, and surpass those of, their constituent materials. However, their functionality is typically compromised by defects and imperfections, which are unavoidable in real world applications. This begs the question of whether a new paradigm exists, whereby a new class of building blocks and interactions enables the design of materials that are robust to imperfections and that are characterized by new functionalities. These studies will demonstrate that concepts from topology provide an organizing principle that gives rise to a wide range of impurity-immune phenomena in areas such as wave guiding, structural stability, and fracture. The project findings will have implications for the design and fabrication of mechanical energy control systems and devices whose operation relies on wave focusing, amplification, localization and attenuation. These include ultrasonic acoustic transducers, sonars, noise absorbing or enhancing devices, and material systems for vibration filtering and impact/blast protection. The objectives of the project will be achieved through the collaboration of a team that combines experts in topological mechanical metamaterials, experimental wave dynamics, linear and nonlinear wave propagation, condensed matter physics and mathematics. This multi-disciplinary approach to research is rich in opportunities for outreach and for broadening participation of underrepresented groups in engineering and science. For example, outreach programs to underrepresented groups will be organized in collaboration with the Museum of Science and Industry in Chicago. This project investigates topological mechanical metamaterials that challenge classical notions in mechanics such as reciprocity, time reversal symmetry and sensitivity to defects. The objective is to investigate their fundamental properties, such as the existence of topological modes in ordered, disordered and amorphous systems, the effects of nonlinearities, as well as energy transport in the bulk. Guided by these studies, the research team will then explore the engineering implications of topological mechanical metamaterials, focusing on wave guiding, structural stability and fracture. These investigations will be conducted on novel experimental platforms ranging from gyroscopic systems as proof-of-concepts, to newly designed continuous systems that have potential for material/structural system development. The research is expected to enable functionalities that shift the paradigm in which dynamic control devices and materials are designed. The team's unique strengths in theory, simulation and experiments provide the combination of skills that are essential for the successful execution of this ambitious research program.