Fibreoptic reflectometric technique for the automatic detection and measurement of surface cracks

Abstract

A new fibreoptic reflectometric technique for the automatic detection and measurement of surface cracks is proposed, described and analysed. A relationship between the system output image and the surface crack distribution is obtained from theory and a crack measurement principle is derived. Analysis of the experimental data obtained using a first laboratory prototype has validated the proposed measurement principle. The results of a second generation prototype confirm that the technique promises to be a valuable tool in practical inspection tasks.