Method for automatically positioning defects of a coupon of flexible material having non-homogeneous characteristics

A method for automatically positioning defects in a coupon of flexible material with non-homogeneous characteristics from which pieces are intended to be cut, comprising the successive steps of:

• obtaining a digital image of the contour of the coupon in its initial state and the position of its defects;
• after repositioning the coupon in a state ready for cutting, obtaining a new digital image of the contour of the coupon;
• superimposing the digital images of the contours of the coupon in its initial state and in its state ready for cutting;
• determining a rotation value to be applied to at least one of the two contours in order to minimize the total surface area of the zones delimited by the two contours that do not overlap;
• applying the rotation value to the position of each defect of the digital image of the coupon in its initial state in order to pre-position each defect inside the digital image of the coupon in its state ready for cutting;
• determining a plurality of geometric transformations to locally minimize the surface area of the zones of the two contours that do not overlap;
• and
• applying to the position of each pre-positioned defect inside the digital image of the coupon in its state ready for cutting, one of the geometric transformations as a function of the position of the defect inside the contour of the coupon in its initial state in order to accurately reposition the defect inside the digital image of the coupon in its state ready for cutting.