FMSG: Shape-programmable elastic-plastic tubes as building blocks for origami

折纸艺术将二维纸张（例如纸张）转换为复杂的 3D 形状。近年来，工程师和科学家已将折纸用于实际应用，包括军事或美国宇航局的可展开结构、可以薄片形式微加工的自折叠机器人，以及对温度或酸度变化等刺激做出反应的执行器。这个未来制造种子资助 (FMSG) 项目将开发管折纸的新概念，其中通过弯曲管而不是片材来实现复杂的 3D 形状。该奖项支持对管折纸的设计和未来制造的基础研究，其规模迄今为止尚未探索。预计管折纸有许多潜在的应用，例如减少复合材料制造等工艺对环境的影响，或者允许更广泛地采用混凝土 3D 打印等环保技术。该项目将保持美国在先进制造业的领先地位，促进科学进步，促进国家繁荣。它将促进塑料加工、计算力学和聚合物科学领域具有不同专业知识的研究人员之间的多学科合作。该研究将支持训练匹兹堡大学的两名研究生以及匹兹堡大学和宾夕法尼亚州立大学的几名本科生研究人员。两家机构都致力于招募代表性不足的少数群体参与研究。研究人员将在本科生和大学预科阶段开展折纸艺术向折纸工程转化的推广活动，以吸引不同的学生进入 STEM 领域。弹塑管折纸的概念基于两个想法。首先，可以利用复合材料中弹性变形与非弹性变形之间的差异来驱动形状变化。第二个是使用弯曲管材（而不是弯曲板材）来创建折纸的概念。该项目将提高对弹塑性复合材料弯曲力学的科学理解，并将这些知识应用于实现管折纸。该项目的主要实验任务是通过共挤出制造双层弹塑管，使用激光在管上产生表面“缺陷”，并量化管对压力的弯曲程度。主要计算任务是开发 3D 有限元模拟来创建变形的预测模型，并使用此类模拟来合理设计近似任何所需弯曲序列所需的缺陷图案。这项未来制造研究得到了材料研究、数学科学以及土木、机械和制造创新部门的支持。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。

The art of origami converts two-dimensional sheets such as paper into complex 3D shapes. In recent years, engineers and scientists have adopted origami for practical applications including deployable structures for the military or NASA, self-folding robots that can be microfabricated in thin sheet form, and actuators that respond to stimuli such as changes in temperature or acidity. This Future Manufacturing Seed Grant (FMSG) project will develop the new concept of tube origami in which complex 3D shapes are realized by bending tubes rather than sheets. This award supports fundamental research on the design and future manufacturing of tube origami, at a scale hitherto unexplored. Numerous potential applications for tube origami are anticipated, e.g. reducing the environmental impact of processes such as composite manufacturing or allowing eco-friendly techniques such as 3D printing of concrete to be adopted more broadly. This project will maintain US leadership in advanced manufacturing, promote scientific progress, and increase national prosperity. It will foster multi-disciplinary collaboration between investigators with diverse expertise in plastics processing, computational mechanics, and polymer science. The research will support the training of two graduate students at the University of Pittsburgh, and several undergraduate researchers at the University of Pittsburgh and the Penn State University. Both institutions are committed to recruiting underrepresented minorities into research. The investigators will conduct outreach at undergraduate and pre-college level on the translation of origami art towards origami engineering to attract diverse students towards STEM fields.The concept of elastic-plastic tube origami is based on two ideas. The first is that the difference between elastic versus inelastic deformation in a composite can be exploited to drive shape changes. The second is the concept of using bending of tubes (rather than bending of sheets) to create origami. This project will improve the scientific understanding of the bending mechanics of elastic-plastic composites and apply that knowledge to implement tube origami. The chief experimental tasks in this project are to manufacture bilayered elastic-plastic tubes by coextrusion, create surface "defects" on the tube using lasers, and quantify the bending of the tubes in response to pressure. The chief computational tasks are to develop 3D finite element simulations to create a predictive model for the deformation and use such simulations for rational design of the defect patterns needed to approximate any desired sequence of bending. This Future Manufacturing research is supported by the Divisions of Materials Research, Mathematical Sciences, and Civil, Mechanical and Manufacturing Innovation.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.