Grid-type sensors using resistance change ratio for micro-crack detection

Abstract

A new sensing technique for detecting micro-cracks is proposed using the grid-type circuit. The location of micro damage can be estimated based on the tendency of resistance change ratio. The construction of a well-defined grid circuit is important to reliably measure the resistances for micro-scale crack detection. Therefore, the electrohydrodynamic (EHD) inkjet printing technology is applied to build the uniform grid-type circuit. A comparison analysis with respect to the resolution of the grid pattern is conducted to estimate more accurately the location of cracks on the grid-type sensor constructed by the EHD technique. In this work, the 10⨯10 and 20⨯20 grid circuits are considered on an identical surface. By measuring the resistance variations between the two endpoints on every grid with respect to each direction, the location of cracks is estimated by a simple algorithm. Finally, the micro-crack point can be detected using the proposed sensing approach. The proposed mechanism shows the ability to accurately detect the location of cracks.