Development of Surface Crack Sensors using Fractal Geometries of Complementary Split Ring Resonators

摘要

This paper introduces novel microwaves-based designs of surface crack sensor topologies with high sensitivity. The proposed sensors are developed based on fractal geometries of complementary split ring resonators (CSRR). The design has attractive features for practical implementation including design simplicity, flexible design parameters and a wide dynamic range of the sensing-related frequency. These features allow the user to easily customize the sensor design to meet specific inspection procedure requirements (i.e. to precisely detect relevant indications and bypass irrelevant ones). The sensor performance has been verified using the full-wave numerical simulation package ANSYS HFSS. A proof-of- concept resonance frequency shift of 620 MHz was obtained for a surface crack having 100-um width and 2mm depth. Topology of the proposed crack sensors achieved more than 25% sensitivity enhancement compared to recently developed CSRR surface crack sensor. This topology was able to detect a 10-um width surface crack with 230 MHz shift in the resonance frequency.