New possibility of objective evaluation of yarn appearance

Abstract: The possibility of new and objective evaluation of yarn appearance wound on the board is described. A statistical method which has previously been used for the evaluation of surface unevenness of flat textile - semivariograms is used. The yarn board appearance is converted into a grey-scale image and the fluctuation in degrees of greyness between square fields in the image is evaluated by semivariogram. This method was applied on standard yarn boards from the standard CSN 80 0704 in addition to real yarn boards. The results of semivariograms constructed from a simulated ideal appearance of yarn on the board are discussed with the aim of introducing an ideal case behaviour of semivariograms. The possibility of using this function for the objective evaluation of yarn board appearance is also discussed.