A Novel UHF RFID Sensor Based Crack Detection Technique for Coal Mining Conveyor Belt

This paper presents the design and analysis of a novel passive Ultra High Frequency (UHF) radio frequency identification (RFID) based sensor for crack detection in coal mining conveyor belts. The proposed sensor is built on an interdigital capacitor (IDC) based resonator integrated with a commercial UHF RFID chip. The paper illustrates the theoretical sensing principles of the sensor along with its design requirements. To enable the operation of the conveyor belt sample in the UHF band, a dielectric characterization of the belt is performed. This characterization helps obtain the material parameters of the belt, such as the dielectric constant and loss tangent. A thorough analysis of the proposed sensor in terms of simulation and experiment is also exemplified in this paper. Both simulated and experimental studies cater to a robust sensor performance for detecting cracks in the conveyor belt environment. The simulated analysis illustrates the variation of different sensing parameters, including impedance, gain, and backscattered power, with respect to different crack widths, orientations, and locations. The experimental results of fabricated sensor prototypes eventually manifest the backscattered power variation of the sensor into the change of received signal strength indicator (RSSI). An extensive analysis of the experimentally obtained results demonstrates that the proposed sensor can reliably and efficiently detect the presence and growth of cracks along with their variation in widths and orientations. The validation of simulated results through experiments essentially lays the basis for adopting machine learning based crack characterization in the future.