Evaluation of Seam Pucker Using Shape Parameters

Abstract

The aim of the paper is to analyse the distribution dynamics of the waves having developed in the place of the stitching
of the details assembled by different technological modes as well as to propose criteria for defect evaluation.
Geometrical shapes of the puckered specimen obtained from captured photos have been analysed. Characteristics of a
creasy contour have been measured as well as dynamics of the values were examined in order to obtain general
distribution tendencies taking into account different development of height and length of waves. For each lightweight
fabric, the inherent wave under different conditions of assembling has been determined. Analysis of geometrical shape
of the projection of the wave profile in the specimen seams demonstrated that waves occupy not the whole working part
of the test sample. This fact influences subjective perception of creasy surface, therefore, complex evaluation of the
defect requires indicators with respect to sharpness of waves and relative length of the creasy portion. The applied
method for assessment of puckering enabled to determine various puckering of the flexible fabrics assembled under
different modes as well as to compare different puckering.