EAGER: Materials and Structures for Novel Strain Gradient Sensors

这一早期探索性研究拨款(EIGER)项目的目标是研究将挠性电(FE)结构用于新型应变梯度传感器(SGS)的可行性，这种传感器可以在非常早期的阶段检测损伤并在线监测损伤的开始和发展。传感器的发展是实现结构健康监测能力的关键使能技术。新的传感材料和传感概念迫切需要对高应变梯度区附近经常发生的早期损伤进行现场监测。这种有限元传感器能够对局部损伤位置附近最敏感的测量应变梯度进行高灵敏的传感。特别是，特征尺寸从毫米到10微米的FE微复合材料将首次被制造并在应变下进行测试，用于应变梯度传感。还将对有限元微结构进行尺度效应研究。这项研究将为新型应变梯度传感器(SGS)奠定基础，它将极大地促进结构损伤传感技术领域的科学和工程知识的发展，并极大地提高结构损伤早期检测和现场结构健康监测的能力。这项研究将通过丰富智能纳米结构和纳米制造的新研究生课程和为K-12学生介绍纳米制造的专业工作坊，将教育活动整合到课程发展中。这一努力还将把这种多学科的奖励带给博士后研究员、研究生和本科生，并纳入推广计划。

The objective of this EArly Grant for Exploratory Research (EAGER) project is to investigate the feasibility of using flexoelectric (FE) structures for a new class of strain gradient sensor (SGS) that can detect damage at a very early stage and in-situ monitor the damage initiation and progression. Advances in sensors are key enabling technologies to the realization of structure health monitoring (SHM) capability. New sensing materials and sensing concepts are in critical need for in-situ monitoring early damage that often occurs near the high strain gradient areas. Such a FE sensor enables high-sensitive sensing of strain gradient which is most sensitive measurand near the localized damage location. In particular, FE micro-composites with feature sizes ranged from mm to 10 microns will be fabricated and tested under strain, for the first time, for strain gradient sensing. Scale effect study on FE microstructures will also be performed. This study will lay the groundwork for a new class of strain gradient sensor (SGS) which will significantly advance scientific and engineering knowledge in the area of structure damage sensing technology and greatly enhance SHM capability of early damage detection and in-situ structural health monitoring. This research will integrate the educational activities in curricular developments by enriching a new graduate course in Smart Nanostructures and Nanofabrications and professional workshops for introducing nanofabrication for K-12 students. This effort would also carry this multidisciplinary bonus to a postdoctoral researcher, graduate and undergraduate students and into the outreach programs.