Dynamic Measurement Of Raw Silk Evenness Based On Machine Vision

Recent researches on various measurements of silk evenness were analyzed andcompared in this paper. on the basis of the existing technologies, a dynamicmeasurement system of raw silk evenness based on machine vision is introduced.When the raw silk is moving at a certain speed by a drive device, the raw silkimages are continuously captured by image acquisition system including a ChargeCoupled Device (CCD) line sensor, a telecentric lens, a light source. The using of linescan CCD sensor can achieve the high-speed accessing the raw silk images;Telecentric lens overcomes the impact of jitter along the optical axis on the themeasurement accuracy during the raw silk is moving. To extract the main body of theraw silk accurately, the raw silk images are processed sequentially with thresholdsegmentation, morphological opening operation. Threshold is used to realize theseparation of raw silk and background, morphological opening operation can eliminatethe protrusion and the loop fiber which surrounding the main body of raw silk in thebinary image. by calculating the change in diameter of raw silk, the coefficient ofvariation (CV value) of diameter is adopted to characterized the raw silk evenness. Inorder to get the raw silk diameter, Programming is based on the concept of Run-LengthEncoding in this paper.The commonly used raw silk which specifications for20/22D is tested, The resultis compared with the the CV value obtained by USTER ME100tester. Based on thedevastation between two results, Specific image processing steps used in the system isconfirmed: Gaussian histogram algorithm is selected in threshold segmentation stepand the square structuring element with size6×6is adopted in morphology processing step. Experimental results show that the application of this system meets therequirements of raw silk evenness measurement, and this method pays more attentio nto changes in in size of raw silk.