Machine vision controlled laser cutting of a non-rigid product

This paper describes a system, developed by the authors, which addresses the difficulties of making precisely placed cuts in a flexible product: textile lace. The problem of cut placement is compounded by the manufacturing variability of the product, resulting in relatively large dimensional variations between, and within, nominally identical product samples. To these may be added local distortions which occur when the tensions within the lace are released by cutting. These variations, which generally do not affect the saleability of the product, obviate `rigid-template´ based approaches to automation. Instead, an approach has been implemented based on machine-visual control, in which the visual data collected is reconciled in real-time with an undistorted map with respect to which the required cutting path has been defined. A machine which performs visually guided longitudinal separation of lace (scalloping) on multiple paths, simultaneously and at high speed (1m/s), using CO₂ laser beams, has been developed and is described