Investigation of effect of woven structure characteristic on brightness of fabric for automatic defect detection application

The quality of a finished textile product depends on the processes of yarn, fabric, finishing and ready-made with starting from fiber properties. Likewise, in order to prevent possible defects in the final product, the raw material, semi materials and processes must be controlled during production. The defects on the textile products can be tested with different ways by laboratory test equipments. The detection of defects which are on the raw fabric or finished fabric is done manually in the quality control machines. The new systems have been developed automatically to perform quality controls of the fabric with image analysis. In these systems, the image of the fabric is transferred to the computer with taking by a camera and then the defect analysis is done by computer with passing the various algorithm processes. Structural characteristics of the fabric affects the change in brightness of fabrics, thus the detectability of defects varies according to the type of fabric. In this study, the effects of fabric structural parameters on the brightness of the fabric and also, the effects of the brightness of the fabric on the defect detection were investigated at the automatic control systems. Three main parameters were focused as the fabric structural parameters which are weave pattern type (plain, twill, saten), cover factor (different weft setts) and fiber type (cotton, poliester, linen and lyocell). Ten different fabric samples were woven related with these three parameters and same size mispick defects were formed to make defect detection analysis at the fabric samples. The brightness of these samples was measured with using spectrometer and image analysis. Matlab and Photoshop programs were utilized as image analysis methods. Then, a coefficient was calculated based on the standard deviation values of Photoshop program. The amount of change of the defect detectability according to the fabric parameters was found with this coefficient at different constructions of the fabric.