The Buckling of Fabrics during Feeding into Automatic Sewing Stations

Abstract

Abstract When a fabric panel is fed into a sewing machine by a robot, it may buckle in one of two modes: compressive buckling or shear buckling. Computational techniques for predicting the onset of buckling are required for off-line programming of robotic feeding systems, and this paper is concerned with predicting compressive buckling. Although a previous analysis of compressive buckling accounted for the fabric's non-linear bending characteristics, it cannot be used to determine the onset of buckling, since it predicts an infinitely large critical buckling force (i.e. the force at the onset of buckling). It is shown that improvements to this analysis, by changing the assumptions regarding the initial non-linearities in bending, are not helpful. In this paper, an empirical method for obtaining the critical buckling force is presented. By using this method, it is shown that the resistance of most fabrics to buckling during feeding can be estimated. The method can also be used to estimate the onset of vertical compressive buckling