CAREER: Mechanics of Kirigami-based Reconfigurable Structures

该教师早期职业发展计划（Career）奖将支持基于kirigami的可重构二维（2D）和三维（3D）结构的力学行为的基础研究。最近，古老的剪纸艺术kirigami激发了新兴的科学研究和工程创新，从机械超材料、可拉伸设备、太阳能跟踪到自组装的3D细观结构。然而，对于切割结构对基里伽米结构宏观力学响应的影响还缺乏基本的认识。该研究项目将建立一个理论框架，将宏观力学行为和基于切割的微观结构联系起来，形成一类新的基于基里伽米的结构，这些结构在2D和3D中都是可重构的。通过该项目开发的知识将推动多种技术的发展，包括可适应和可拉伸电子产品的支架、电子皮肤、自适应节能建筑围护结构、可编程软机器、软机器人和可重构声波波导。教育和推广目标将与更好地理解基里伽米结构的力学和结构决定的性质和功能的研究目标保持一致。坦普尔大学和费城博物馆的项目将用于扩大K-12学生对STEM的参与，包括坦普尔大学的女性工程探索暑期项目和STEM教育部门，以及费城的科学博物馆展览（富兰克林研究所）和艺术展（费城艺术博物馆）。基于kirigami的2D/3D结构将通过在平面薄片和块状材料上应用设计的切口和/或折叠来构建，以便在外力或外部刺激下驱动。系统的理论框架将发展，以预测运动学和本构建模的二维和三维基利伽米结构，并通过数值模拟，制造和实验测试验证。对于二维结构，统一的图案切割设计将兼顾对称和非对称变形。通过发展的均质连续体模型，确定整体力学性能与局部切削结构几何之间的定量关系。三维可重构的基里格米结构将由基里格米片的（自）折叠或三维切割多面体单元的组装构成，作为建筑结构的基本构建块。对于三维结构，其可重构性和力学性能将由局部三维切割单元的变形模式决定。通过小变形和有限变形的模态分析，建立预测整体变形模态的理论框架。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。

This Faculty Early Career Development Program (CAREER) award will support fundamental research on the mechanical behavior of kirigami-based reconfigurable two dimensional (2D) and three dimensional (3D) structures. Very recently, kirigami, the ancient paper cutting art, has inspired emerging scientific research and engineering innovations, ranging from mechanical metamaterials, stretchable devices, and solar tracking, to self-assembled 3D meso-structures. However, it largely lacks the fundamental understanding of cut-structures determined macroscopic mechanical response of kirigami structures. This research program will establish a theoretical framework for connecting the macroscopic mechanical behavior and cuts-based microstructures in a new class of kirigami-based structures, which are reconfigurable in both 2D and 3D. The knowledge developed through this project will advance multiple technologies, including scaffolds for conformable and stretchable electronics, electronic skin, adaptive energy efficient building envelope, programmable soft machines, soft robots, and reconfigurable acoustic wave guides. The education and outreach objectives will align with the research goal in generating better understanding of mechanics and structure-determined properties and functionalities in kirigami structures. Programs at Temple and museums in Philadelphia will be used to broaden the participation of K-12 in STEM, including Women's Engineering Exploration summer program and STEM education department at Temple, as well as Science museum displays (Franklin Institute) and Art show (Philadelphia Museum of Art) in Philadelphia. Kirigami-based 2D/3D structures will be constructed by applying designed cuts and/or folds to both planar sheets and bulk materials for actuation under forces or external stimuli. Systematic theoretical framework will be developed to predict the kinematics and constitutive modeling of 2D and 3D kirigami structures, with validation by numerical simulation, fabrication, and experimental testing. For 2D structures, a unified design of patterned cuts will account for both symmetric and non-symmetric deformation. The quantitative relationship between the overall mechanical properties and the geometry of localized cut structures will be determined through developed homogenization continuum model. 3D reconfigurable kirigami structures will be constructed from either (self-) folding of kirigami sheets or assembly of 3D cut polyhedron units as fundamental building blocks for architected structures. For 3D architected kirigami structures, their reconfigurability and mechanical properties will be determined by the deformation modes in localized 3D cut units. A theoretical framework will be developed to predict the overall deformation modes through mode analysis under both small and finite deformation.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.