الفهرس 
IntroductiionOnly 14 pages are availabe for public view
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Abstract
An optical measurement system was established to measure pick density variation from a unit length to another. The measuring system consists of a mechanical unit to simulate the take-up of fabric on the weaving machine and two optical systems. The first optical system detects picks that cut the path of a laser beam and the second monitors passing of the fabric unit lengths. Two electrical signals were obtained as output from the two systems. The signals were recorded simultaneously using a digital storage oscilloscope. Signals Analysis was then carried out using designed computer software programs. Measuring results of density and determination of its variation from a unit length to another showed exact coincidence with manual measurements by conventional means. Yarn diameter and gab distance between yarns were measured and hence individual yarn spacing were determined. Yarn spacing variation due to cloth fell displacements, double pick and course pick defects were detected and assessed. Also, the irregularity of weft thread diameter was assessed and weft thread count was estimated. The system was also used to estimate the fabric dimensional properties using suitable geometrical models. The system could be used as on-line system for measuring pick density variation on weaving machines or as a new testing apparatus for fabric analysis.