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CAREER: The Mechanics of Hierachically Multistable Metastructures

职业：分层多稳态元结构的力学

基本信息

批准号：
1944597
负责人：
Andres Arrieta
金额：
$ 54.16万
依托单位：
Purdue University
依托单位国家：
美国
项目类别：
Standard Grant
财政年份：
2020
资助国家：
美国
起止时间：
2020-08-01 至 2025-07-31
项目状态：
未结题

来源：
https://www.nsf.gov/awardsearch/showAward?AWD_ID=1944597&HistoricalAwards=false
关键词：
CAREER Mechanics Hierachically Multistable Metastructures

项目摘要

This Faculty Early Career Development (CAREER) grant will support research investigating the mechanics of a new class of material systems exhibiting intrinsic reshaping and property adaptation. Conventional engineering materials have fixed macroscopic properties that are derived from specific atomic compositions. This limits the available design possibilities when compared to biological systems that exhibit many unconventional and time-varying properties, like inherent self-shaping. This biological characteristic can be attributed to unique microstructures comprising hierarchical geometrical arrangements, spanning several length scales. A unique geometrical characteristic enabling property adaptation is multistability; i.e. a system’s capacity to exhibit several coexisting states. Pursuing this concept, this research aims to derive models to harness (locally) multistable arrangements, or metastructures, that display macroscopic adaptability from changes at the local scale. Understanding the mechanics of such multistable structures will facilitate the development of advanced structures and robotic materials relevant to the aerospace, biomedical and robotics industries. This will expand the U.S. scientific and technological edge, ultimately benefiting the economy and society at large. Furthermore, this effort’s multidisciplinary (engineering and material science) nature allows for promoting STEM education. This is pursued by establishing teaching strategies for courses with multidisciplinary content and offering design experiences partnering undergraduate and graduate students.The novel concept of hierarchical multistability in material systems entails the appearance of multiple coexisting global configurations for a single combination of local (multistable) states, thereby breaking the one-to-one correspondence between local and global states commonly found in multistable metamaterials. The objective of this project is to understand the fundamental mechanics responsible for the manifestation of hierarchical multistability. Specifically, this effort aims to determine the local (unit-cell) and global (metastructural) interaction mechanisms responsible for the appearance of hierarchical multistability. The central hypothesis is that long-range effects in the strain field develop compliant deformation modes in the metastructure due to local distortions introduced from changes of state at the unit scale. Building on this hypothesis and departing from considering nearest-neighbor coupling, this research aims to derive long-range interaction models between unit cells. The characteristics of hierarchical multistability opens novel avenues for designing programmable structures that couple sensing, computation and property adaptation. The resulting metastructures are relevant to the aerospace, biomedical and robotic industries. Furthermore, the results from this effort are leveraged to develop an educational plan to encourage multidisciplinary STEM education and research by: 1) offering multidisciplinary design experiences partnering with Purdue University’s EPICS program; and 2) establishing pedagogical strategies for teaching courses with multidisciplinary content.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.

这笔学院早期职业发展(Career)补助金将支持研究一种新的材料系统的力学机制，这种材料系统表现出内在的重塑和性能适应。传统的工程材料具有固定的宏观性质，这些性质源于特定的原子组成。与生物系统相比，这限制了可用设计的可能性，生物系统表现出许多非传统和时变的特性，如固有的自我塑造。这种生物学特征可以归因于独特的微结构，包括跨越几个长度尺度的分层几何排列。使属性适应的一个独特的几何特征是多稳定性；即，一个系统展现出几种共存状态的能力。追寻这一概念，这项研究的目的是建立模型，以驾驭(局部)多稳定安排或元结构，这些安排或元结构从局部尺度的变化中表现出宏观适应性。了解这种多稳态结构的力学原理将有助于开发与航空航天、生物医学和机器人行业相关的先进结构和机器人材料。这将扩大美国的科技优势，最终造福于整个经济和社会。此外，这一努力的多学科性质(工程和材料科学)允许促进STEM教育。这是通过为多学科内容的课程制定教学策略并为本科生和研究生提供合作设计经验来实现的。材料系统中分层多稳定性的新概念需要出现局部(多稳态)的单一组合的多个共存的全局构型，从而打破在多稳态超材料中常见的局部和全局状态之间的一对一对应。本项目的目标是了解导致等级多稳定性表现的基本机制。具体地说，这项工作旨在确定导致分层多稳定性出现的局部(单位-细胞)和全局(元结构)相互作用机制。中心假设是，应变场中的长期效应在亚结构中发展了柔顺变形模式，这是由于单位尺度上的状态变化引入的局部扭曲。基于这一假设，本研究从考虑近邻耦合出发，旨在推导出单元细胞之间的远程相互作用模型。层次化的多稳定性特性为设计耦合传感、计算和性能自适应的可编程结构开辟了新的途径。由此产生的元结构与航空航天、生物医学和机器人行业相关。此外，这一努力的结果被用来制定一项教育计划，通过以下方式鼓励多学科STEM教育和研究：1)与普渡大学的EPICS计划合作提供多学科设计经验；2)为教学具有多学科内容的课程建立教学战略。该奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。