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著地增长，但对这些材料进行快速而可靠的无损检测仍然是一个未满足的要求。特别是，在石油和天然气行业，复合管道正在迅速取代金属管道，以对抗腐蚀。然而，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，因为超声波检测和其他方法适用于金属部件而不适用于复合材料。因此，为了弥补这一差距，在本项目中，微波成像技术将用于圆柱形复合材料部件和同心管的体积检测。该成像技术快速可靠，可用于多种复合材料的检测。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，降低组件故障的风险。该项目的实施将大大加强纽约理工学院的研究和教育基础设施。为该项目获得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，包括女性和来自电气工程领域代表性不足的少数群体的个人，将接受天线和微波设计方面的实践培训，使用最先进的硬件和软件，从而获得一套独特的技能，为他们满足国家高科技产业的需求做好准备。这些活动对少数民族和妇女具有积极和社会相关的结果，有助于消除参与电气工程和工程教育的障碍。提出的微波成像技术是基于全息成像的概念，已经在安全检查和其他应用中被证明是成功的。这些技术速度快，抗噪能力强。它们将被修改，用于诸如复合管道的无损检测等应用，其中物体位于天线的极端近场，其物理尺寸不容忽视。与以前的近场全息成像技术相比，使用圆形反褶积概念的改进技术将解决圆柱形成像设置中沿方位角方向的函数周期性。此外，将改进近场全息的求解过程，以减少对距离天线较远的特征的低估。这种改进将通过一种最初用于基于脑电图（EEG）的脑源定位的方法来实现。此外，将研究新的微波断层成像技术，以减轻在全息技术中使用玻恩近似所施加的限制。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效率高的新型微波断层扫描技术。这将允许检查更大和更高的对比度缺陷。将研究成像的两种配置：(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分辨率的参数，包括频率数量、天线数量、天线之间的角距离和成像表面之间的径向距离。所提出的技术的有效性将通过模拟和实验设置来证明。此外，使用射频数据采集电路和定制设计的天线阵列，将开发一种紧凑且具有成本效益的成像装置。这种新的微波检测技术可能会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。

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.