RUI: Fast and Robust Non-Destructive Testing of Cylindrical Composite Components Based on Microwave Measurements

尽管复合材料和非金属部件的使用迅速而显着增长，但对这些材料进行快速、稳健的无损检测仍然是一个未满足的要求。特别是，复合管道正在迅速取代石油和天然气行业中的金属管道以对抗腐蚀。然而，由于超声波检测和其他适用于金属部件但不适用于复合材料的方法的挑战，传统的无损检测技术无法用于评估这些由复合材料制成的部件。因此，为了弥补这一差距，在该项目中，微波成像技术将用于圆柱形复合材料部件和同心管道的体积检查。该成像技术快速可靠，可用于检测各种应用中的各种复合材料。这项新技术可以提供关键的材料完整性数据，有助于降低成本、提高系统安全性并降低组件故障的风险。该项目的实施将显着增强纽约理工学院的研究和教育基础设施。该项目购买的设备将用于开发微波/天线工程领域的研究和教育计划。研究生和本科生，包括来自电气工程领域代表性不足的女性和少数群体的个人，将使用最先进的硬件和软件接受天线和微波设计的实践培训，从而获得一套独特的技能，为满足国家高科技产业的需求做好准备。这些活动对少数族裔和妇女产生了积极的、与社会相关的成果，有助于消除参与电气工程和工程教育的障碍。所提出的微波成像技术基于全息成像概念，该概念已在安全检查和其他应用中被证明是成功的。这些技术快速且对噪声具有鲁棒性。它们将针对复合材料管道的无损检测等应用进行修改，其中物体位于天线的极近场中，其物理尺寸不容忽视。与以前的近场全息成像技术相比，使用圆形反卷积概念的修改技术将解决圆柱成像设置中沿方位角方向的函数的周期性。此外，近场全息术的求解过程将得到改进，以减少对远离天线的特征的低估。这一改进将通过最初用于基于脑电图 (EEG) 的脑源定位的方法来实现。此外，还将研究新型微波断层扫描技术，以减轻全息技术中使用玻恩近似所带来的限制。在这项任务中，全息技术将与非线性成像方法相结合，设计出在成本和时间方面都很高效的新型微波断层扫描技术。这将允许检查更大和更高对比度的缺陷。将研究两种成像配置：（1）宽带单接收器天线和（2）窄带多接收器天线。将研究影响每种配置中分辨率的参数，包括频率数量、天线数量、天线之间的角距离以及成像表面之间的径向距离。所提出技术的有效性将通过模拟和实验设置来证明。此外，还将使用射频数据采集电路和定制设计的天线阵列开发紧凑且经济高效的成像装置。这种新的微波检测技术有可能彻底改变复合材料和非金属材料的无损检测。该奖项反映了 NSF 的法定使命，并通过使用基金会的智力价值和更广泛的影响审查标准进行评估，被认为值得支持。

Despite the rapid and significant growth in the use of composite and non-metallic components, fast and robust non-destructive testing of these materials is still an unfulfilled requirement. In particular, composite pipes are rapidly replacing metallic pipes in the oil and gas industry to combat corrosion. However, traditional non-destructive testing techniques cannot be employed for assessment of these components made of composite materials, due to the challenge of ultrasonic testing and other methods suitable for metallic components but not for composite materials. Thus, to bridge this gap, in this project, microwave imaging technology will be employed for volumetric inspection of cylindrical composite components and concentric pipes. The imaging technology is fast and reliable, and it can be employed for inspection of a vast range of composite materials in various applications. This novel technology can provide crucial material integrity data that could help reduce costs, increase system safety, and reduce the risk of component failures. Implementation of this project will significantly enhance the infrastructure for research and education at New York Institute of Technology. The equipment acquired for this project will be used to develop a research and education program in the field of microwave/antenna engineering. Graduate and undergraduate students, including females and individuals from minority groups underrepresented in the electrical engineering field, will receive practical training in antenna and microwave design using state-of-the-art hardware and software, and thus acquire a unique skill set that prepares them for the demands of the national high-tech industry. These activities have positive and societally relevant outcomes for minorities and women, helping to remove barriers to participation in electrical engineering and engineering education in general.The proposed microwave imaging technique is based on holographic imaging concepts already proved successful in security screening and other applications. These techniques are fast and robust to noise. They will be modified for applications such as non-destructive testing of composite pipes, in which the objects are in the extreme near-field of the antennas whose physical size cannot be ignored. In contrast to previous near-field holographic imaging techniques, the modified techniques using circular deconvolution concept will address the periodicity of the functions along the azimuthal direction in a cylindrical imaging setup. Furthermore, the solution process in near-field holography will be improved to reduce underestimation of features that are farther away from the antennas. This improvement will be implemented via an approach originally used for electroencephalography (EEG)-based brain source localization. Furthermore, novel microwave tomography techniques will be studied to alleviate the limitations imposed by the use of Born approximation in holographic techniques. In this task, holographic techniques will be combined with nonlinear imaging approaches to devise new microwave tomography techniques that are efficient in terms of cost and time. This will allow inspection of larger and higher contrast defects. Two configurations will be studied for imaging: (1) wideband single-receiver antennas and (2) narrow-band multiple-receiver antennas. Parameters affecting resolution in each configuration, including number of frequencies, number of antennas, angular distance between antennas, and radial distance between imaged surfaces, will be studied. Validity of the proposed techniques will be demonstrated via simulation and experimental setups. In addition, a compact and cost-effective imaging setup will be developed using RF data acquisition circuitry and custom-designed antenna arrays. This new microwave inspection technology can potentially revolutionize the non-destructive testing of composite and non-metallic materials.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.