CPS: Medium: Collaborative Research: Scalable Intelligent Backscatter-Based RF Sensor Network for Self-Diagnosis of Structures

该网络物理系统（CPS）资助将通过依靠一种具有前所未有的可扩展性和空间分辨率的新型传感技术获得的数据，推进混凝土结构的结构健康监测。现代社会严重依赖于各种工程结构和基础设施的健全和稳定的功能，如桥梁、建筑物、管道、岩土结构、飞机、风力涡轮机和工业设施。由于老龄化、大规模城市化和气候变化，越来越需要对这些结构的健康状况、性能和运行进行准确可靠的评估，以确保其持续运作和安全使用。该技术通过将混凝土转化为智能自感知材料，实现对混凝土结构的高分辨率无所不在和可扩展的感知，从而实现可靠的长期结构健康监测。这反过来又有助于国家的可持续性和弹性，并促进国家的繁荣、福利和安全。该项目推进了结构健康监测的多个核心研究领域，包括使用嵌入式设备的CPS系统架构，基于射频传感器的多参数传感和网络，以及用于准确可靠数据分析的机器学习。研究成果对其他CPS领域具有很强的可转译性。该项目还以多种方式为中学教育和外联活动以及本科和研究生教育作出贡献。该项目的目的是创建一种新的传感系统，该系统由广泛嵌入大量混凝土结构中的射频传感器组成，并利用射频特性感知其位置。目标是评估反映被监测结构在运行条件下行为的关键参数，如变形、温度和湿度，以及损伤的检测和表征。该项目有以下智力贡献：1)在宽频率范围内工作的基于无源射频的传感；智能激励器和通过反向散射调制相互通信的网络射频传感器的架构；为传感器供电的太阳能射频激励器平台。2)在励磁器可用采集功率约束下，基于能量的射频传感器网络监测能力和网络连通性的传感与网络优化。3)基于高斯过程集成建模原理的函数估计机器学习方法，应用于自定位和大体积混凝土结构内材料参数三维分布的推断。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 Cyber-Physical Systems (CPS) grant will advance structural health monitoring of concrete structures by relying on data acquired by a novel sensing technology with unprecedented scalability and spatial resolution. Modern society depends critically on sound and steadfast functioning of a variety of engineering structures and infrastructures, such as bridges, buildings, pipelines, geotechnical structures, aircrafts, wind turbines, and industrial facilities. Due to aging, massive urbanization, and climate change, there is a growing need for accurate and reliable assessment of the health condition, performance, and operation of these structures in order to ensure their continuous functioning and safe use. The researched technology enables pervasive and scalable sensing of concrete structures with high resolution by transforming concrete into a smart self-sensing material, thereby enabling reliable long-term structural health monitoring. This in turn contributes to the nation’s sustainability and resilience and to advancing the nation’s prosperity, welfare, and security. The project advances multiple core research areas in structural health monitoring including CPS system architectures using embedded devices, multi-parameter sensing and networking based on radio frequency sensors, and machine learning for accurate and reliable data analytics. The research outcomes are highly translational to various other CPS domains. The project also contributes to secondary education and outreach activities in multiple ways as well as to undergraduate and graduate education. The aim of this project is to create a novel sensing system comprised of radio frequency sensors that are pervasively embedded in large volumes of concrete structures and that sense their localities using radio frequency properties. The objective is the assessment of key parameters that reflect the behavior of the monitored structure under operational conditions, such as deformation, temperature, and humidity, as well as detection and characterization of damages. The project has the following intellectual contributions: 1) Passive radio frequency-based sensing that operates over a wide range of frequencies; architectures of smart exciters and networked radio frequency sensors that communicate among themselves via backscatter modulation; solar-powered radio frequency exciter platform that powers the sensors. 2) Energy-based sensing and network optimization of the radio frequency sensor network in terms of its monitoring ability and network connectivity given the constraints on the available harvested power at the exciters. 3) Machine learning methods for function estimation based on the principle of ensemble modeling with Gaussian processes and applied to self-localization and to inference of three-dimensional distributions of material parameters within large volumes of concrete structures.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.