A Noncontact Feed Microwave Metal Devices Deformation and Stress Sensor Based on Metamaterial

In this article, a noncontact feed microwave metal deformation and stress sensor based on microwave harvesting metamaterial (MHMA) is proposed. It integrates HMA array, feed network, and complementary cross-finger split-ring resonator detector (CFSRRD). The sensor can be applied in the detection system composed of waveguide antenna (WA at 10 GHz) and vector network analyzer (VNA). In the processing of monitoring, the signal emitted by WA will be captured by the MHMA array and output to CFSRRD through the feed network. Then the response signal of CFSRRD will be returned to WA and analyzed by VNA. From the analysis results, the deformation information of metal device will be obtained. Combined with the initial conditions of metal devices, the stress mutation information can be further obtained. Simulation and measurement results show that the designed sensor can detect the metal pipeline deformation caused by external force, pressure, or high temperature with a reliable accuracy level of 500 μm (submillimeter Level), and the minimum detectable radius of pipe is 30 mm. It has the advantage of simple structure, strong adaptability, and overcomes the shortcoming that traditional detection methods are difficult to detect the operating state of metal devices in a complex environment.