Determination of yarn hairiness using optical sensors

Abstract

Yarn quality higly depends of the level of homogeneity of yarn- unevnness, wich quantifies the mean variation in linear density of strand or part of it. These irregularities are detected using capacitive sensors which, in commercial equipments, perform yarn analysis in steps of 8mm ; MPS1 performs 1mm analysis. These increase in resolution enables direct detection as most yarn irregularities occur in lengths between 1mm and 4mm[1]. Another important feature of yarn is hairiness, which can also significantly affet the appearance of fabrics. Its measurement is usually undertaken using optical sensors for samples of 2mm or less; MPS1 upgrade performs hairiness yarn analysis in 1mm samples. It is possible to determine all important yarn parameters for evaluating yarn quality using capacitive and optical sensors measurements, together with signal processing techniques.