EVALUATION OF THE PARAMETERS OF NARROW SURFACE-DEFECTS USING FOURIER DESCRIPTORS OF THE TOPOGRAPHY OF THE MAGNETIC-FIELD

The authors describe a method of classifying a narrow slit-like surfac e defect on the basis of the angle of inclination and depth using Four ier descriptors of the contour of the topography of the horizontal com ponent of the leakage field for the current model [1]. They examine a method of defining the boundary of the classification region with an a llowance made for the finite width of the window of counting the topog raphy of the field and results of calculating the boundaries of cluste rs for a representative teaching sample of modeling defects. It is sho wn that the classification evaluation of the geometrical parameter can be made more accurate using isolines of the apparent component of the fourth descriptor and the dependence of the apparent component of the first descriptor on the angle of inclination and the depth of defects to which these isolines correspond.