Passive flexible chipless RFID strain detection system

A crack detection device relates to a displacement detection technology, in particular to a crack detection technology, and is characterized in that under the control of a main controller, a radio frequency identification (RFID) reader continuously sends out a radio frequency excitation signal, a chipless RFID sensor printed on the surface of an object to be detected generates a response signal related to the structure of the chipless RFID sensor after receiving the excitation signal, and the chipless RFID sensor transmits the response signal to the main controller after receiving the response signal. And the main controller performs frequency characteristic analysis on the response signal, judges whether the frequency point of the response signal deviates or not, and controls the alarm module to work and sends out an alarm signal if the deviation amount reaches an early warning value. Compared with the prior art, the crack detection device has the advantages that cracks can be detected, and objects can be co