无源无芯片RFID的金属构件裂痕传感器

Passive chipless RFID-based crack sensor for metal components

摘要:

为满足对大规模建筑群体的低成本、长期检测需求,并扩大传感器识别范围,提出一种基于无源无芯片射频识别技术的金属构件裂痕传感器。依据交叉极化和工作带宽等影响因素及前期在HFSS平台上的大量仿真数据,设计满足优良检测性能的传感器模型；构建水平、垂直、对角裂痕,利用平面波电磁激励,检验不同裂痕形状对传感检测的影响；改变各类裂痕位置,分析谐振腔电场、电流与响应幅值变化,确定传感器最优识别范围。结果表明:在超高频段下,传感器对结构损伤检测响应的平均幅值偏差为5 dB；裂痕位置变化影响表面电流分布,进而改变响应幅值,而相较于无裂痕响应,结构损伤响应均呈现失谐状态,裂痕位置变化不影响其可检测性。该传感器可对物体表面任意位置的不同方向裂痕实现全范围检测,识别范围提高,且能够以较高分辨率对微小位置变化的裂痕进行实时监测。

Abstract:

In order to realize the demand for low-cost and long-term detection of large-scale building groups and to expand the identification range of the sensor, this paper proposed a metal crack sensor based on passive chipless radio frequency identification (RFID) technology. Based on the influencing factors such as cross-polarization and operating bandwidth and a large amount of simulation data on the HFSS platform in the early stage, the paper designed a sensor model with excellent detection performance. Horizontal, vertical, and diagonal cracks were constructed, and electromagnetic excitation of the plane wave was used to test the influence of different crack shapes on the sensing and detection. The position of various types of cracks was changed, and changes in the electric field of the resonant cavity, current, and response amplitude were analyzed to determine the optimal identification range of the sensor. The results show that the average amplitude deviation of the sensor’s response to structural damage detection is 5 dB in the ultra-high frequency band. The change of crack position will affect the surface current distribution, which will change the response amplitude, while the structural damage response is detuned compared with the crack-free response, and the change of crack position does not affect the detectability of cracks. The sensor is capable of detecting cracks in different directions at any position on the surface of an object over a full range, improving the identification range and enabling real-time monitoring of cracks with small positional variations at a high resolution.