Yarn Evenness Parameters Evaluation: A New Approach

This paper presents MPS1 (Mass Parameterization System), an automatic system for determination of mass characteristics of textile yarn. It is based on 1 mm parallel capacitive sensors, working online or offline. This new approach allows direct measurement of yarn mass in the 1 mm range (increasing the resolution by eight times) [Pinto, J. G., Dissertação de Mestrado, Minho University, 2004; Baxter, L. Capacitive sensors: design and applications, IEEE Press, 1997]. Acquisition and data processing are performed in Labview™ from National Instruments. All parameters commonly used in the textile industry are determined for different values of sensitivity defined interactively by the operator. In MPS1, the new parameters were used (integral of deviation rate [IDR%], signal processing techniques based on the fast Walsh-Hadamard Transform and on fast impulse frequency determination [FDFI]) and others adapted (deviation rate [DR%], spectograms, frequency and mass variation diagrams, coefficient of variation [CV%], mean deviation [U%], faults counting and extension). Anew feature of this system is also the online automatic quality classification of mass parameters.