Tunable Tensegrity Structures and Metamaterials

张拉整体是由受压支柱组成的特殊结构，这些受压支柱通过处于预应力状态的连续拉索网络连接。这些结构表现出极端的特性，例如低质量和重量、高弹性、高强度和丰富的可调性。这些特性可用于工程应用，并有可能超越当前已建立的解决方案的性能。此外，张拉整体结构已用于越来越多的工程应用，包括可展开圆顶、可调谐天线和可持续自适应太阳能电池阵列等。从几何角度来看，张拉整体已被证明是可扩展的：从大空间结构到微米和纳米尺度的应用已经证明了它们的跨尺度适用性。尽管许多人认为预应力要求是张拉整体结构进一步发展的障碍，但该项目通过继续检验预应力要求使张拉整体可部署、可调节和可变形的前提，探索了这一新兴趋势。该研究项目将贡献理论、计算和实验能力，以推进张拉整体结构和超材料领域的发展，并发现张拉整体功能的新模式。除了向公众和研究界广泛分享研究者的经验之外，还将通过建立基于课程开发、培训示范和通过传播我们的研究结果和工具来提高对这些结构的认识的灵活的教育和外展计划来补充该研究。该研究的目标是深入了解张拉整体，以便：（i）设计或找到任何几何形状的张拉整体，可能存在孔和开口，从而允许特定应用的张拉整体设计； (ii) 使用增材制造进行快速原型制作和新设计的概念验证； (iii) 建造和制造大规模的面向应用的张拉整体结构（例如人体规模），记录经验，并传播挑战和解决方案； (iv) 设计可编程/可重新编程的基于张拉整体的超材料，并使用布洛赫波分析框架研究其动态特性； (v) 研究预应力水平对改变张拉整体超材料内带隙尺寸和分布的影响。具体来说，该项目应导致创建和分析优雅的 1 级（“浮动支柱”）可重编程张拉整体超材料，以及可用于临时避难所或结构部件保护等设计的大型张拉整体结构。因此，它将推进结构、理论和计算力学、制造和材料工程方面的知识基础。该奖项反映了 NSF 的法定使命，并通过使用基金会的智力价值和更广泛的影响审查标准进行评估，被认为值得支持。

Tensegrities are special structures composed of compression struts connected by a continuous network of tension cables in a state of prestress. These structures exhibit extreme properties such as low-mass and weight, high-resilience, high-strength, and rich-tunability. These properties can be harnessed for use in engineering applications and potentially exceed the performance of currently established solutions. In addition, tensegrity structures have been used in an increasing number of engineering applications, including deployable domes, tunable antennas, and sustainable adaptive solar arrays to name a few. From a geometrical perspective, tensegrities have been shown to be scalable: applications ranging from large space structures to the micro and nano scales have proven their cross-scale applicability. Although many have viewed the prestress requirement as a hindrance to further development of tensegrity structures, this project explores this burgeoning trend by continuing to examine the premise that prestress requirements enable tensegrities to be deployable, tunable, and morphable. This research project will contribute theoretical, computational and experimental capabilities to advance the field of tensegrity structures and metamaterials, and to discover novel modes of tensegrity functionality. The research will be complemented by establishing a flexible educational and outreach program based on curriculum development, training demonstrations, and increasing awareness of these structures by disseminating our findings and tools, in addition to sharing investigator experiences broadly to the public and research communities. The goal of the research is to achieve a deep understanding of tensegrities in order to: (i) design or find tensegrities in any geometry, with the possibility of holes and openings, allowing for application specific tensegrity designs; (ii) use additive manufacturing to conduct rapid prototyping and proof of concept of new designs; (iii) construct and manufacture large-scale application-oriented tensegrity structures (e.g. human-scale), document the experience, and disseminate the challenges and solutions; (iv) design programmable/reprogrammable tensegrity-based metamaterials and study their dynamic characteristics using a Bloch wave analysis framework; and (v) investigate the influence of prestress level to change the size and distribution of band gaps within the tensegrity metamaterial. Specifically, this project should lead to the creation and analysis of elegant Class-1 (“floating struts”) reprogrammable tensegrity metamaterials, and large-scale tensegrity structures which may be used in the design of temporary shelters or structural component protection, among others. As such, it will advance the knowledge base in structures, theoretical and computational mechanics, manufacturing, and materials engineering.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.