Folding, crumpling and entangling of sheets and filaments

片材和长丝的折叠、起皱和缠结

• 批准号: 2005090
• 负责人: Arshad Kudrolli
• 金额: $ 48.78万
• 依托单位: Clark University
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2020
• 资助国家: 美国
• 起止时间: 2020-06-15 至 2025-05-31
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2005090&HistoricalAwards=false
• 关键词: Folding; crumpling; entangling; sheets; filaments

Nontechnical Abstract:The goal of the project is to study large shape transformations of thin sheets and filaments when twisted while being held under tension, using noninvasive 3D laser and x-ray scanning techniques. The study will relate the evolution of the structure to its strength in terms of its torsional response far above the onset of initial buckling and after they come in self-contact. The study will focus on complementary hyperelastic materials which can stretch significantly compared to their size, and inextensible materials which bend and deform plastically. The element-level measurements of the internal structure will be analyzed in terms of physical models which incorporate their geometry and elasticity response. Fundamental understanding of the shape and strength of elastomers under large deformations will impact the development of a wide range of materials, including functional yarns and synthetic tissues. The results will be published in peer reviewed journals and will increase scientific knowledge in the field of condensed matter physics and will be disseminated freely via the internet. The project work will support undergraduate student internships and the research work of graduate students towards their dissertations. The research and mentoring activity will result in educating undergraduate and graduate students pursuing careers in STEM related disciplines, and outreach activities to K-12 students. Technical Abstract:The goal of the project is to study topological transformations of thin sheets and filaments as they are driven to collapse and self-packing under extreme boundary loading. The geometry as a function of applied boundary loading will be obtained using noninvasive 3D laser and x-ray scanning techniques and characterizing the surface curvatures and energetics. The study will focus on complementary reversible and irreversible strain-transformed materials in the nonperturbative deformation regime beyond the reach of classical elasticity theories. A filament model based on the origami kinematics will be developed to explain the emergence of self-folds, twist localization and helical wrapping. Damage networks will be analyzed with random and spatially correlated fold algorithms to identify the processes that shape sheet singularities, and their compliance under repeated quenching using torque measurements. The relative contribution of the elasticity of the elements and the contact mechanics will be probed to understand the shaping of yarns and tissues. The results will be published in peer reviewed journals and will increase scientific knowledge in the field of condensed matter physics, biomaterials, and rapid prototyping. The research and mentoring activity will result in educating multi-generational groups of students pursuing careers in STEM related disciplines. The project work will support undergraduate student internships and the research work of graduate students towards their dissertations.This DMR grant supports research on topological transformation of sheets and filaments under extreme stress with funding from the Condensed Matter Physics (CMP) Program in the Division of Materials Research of the Mathematical and Physical Sciences Directorate.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.

摘要：该项目的目标是利用非侵入性3D激光和x射线扫描技术，研究薄板和细丝在被拉伸时扭曲的大形状变化。该研究将把结构的演变与它的强度联系起来，就其扭转响应而言，远高于初始屈曲的开始和之后，它们进入自接触。研究将集中在互补的超弹性材料上，这种材料与它们的尺寸相比可以显著拉伸，而不可扩展的材料可以弯曲和塑性变形。内部结构的单元级测量将根据包含几何和弹性响应的物理模型进行分析。对弹性体在大变形下的形状和强度的基本理解将影响包括功能纱线和合成组织在内的广泛材料的发展。研究结果将发表在同行评议的期刊上，并将增加凝聚态物理领域的科学知识，并将通过互联网自由传播。项目工作将支持本科生实习和研究生的论文研究工作。这项研究和指导活动将为从事STEM相关学科的本科生和研究生提供教育，并为K-12学生提供外展活动。技术摘要：该项目的目标是研究薄板和细丝在极端边界载荷下被驱动坍塌和自包装时的拓扑变换。利用非侵入性三维激光和x射线扫描技术并表征表面曲率和能量学，将获得作为应用边界载荷函数的几何形状。本研究将集中在经典弹性理论所不能及的非摄动变形状态下的互补可逆和不可逆应变转换材料。一个基于折纸运动学的细丝模型将被开发来解释自折叠，扭转定位和螺旋缠绕的出现。损伤网络将使用随机和空间相关的折叠算法进行分析，以识别形成薄板奇点的过程，以及它们在使用扭矩测量重复淬火下的依从性。为了更好地理解纱线和组织的成形过程，我们将探讨各个单元的弹性和接触力学的相对贡献。研究结果将发表在同行评议的期刊上，并将增加凝聚态物理、生物材料和快速成型领域的科学知识。研究和指导活动将导致教育多代学生群体在STEM相关学科的职业生涯。项目工作将支持本科生实习和研究生的论文研究工作。这项DMR拨款支持极端应力下薄片和细丝的拓扑变换研究，资金来自数学和物理科学理事会材料研究部的凝聚态物理（CMP）项目。该奖项反映了美国国家科学基金会的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。