An application of machine vision for automating the manufacture of cork stoppers

Most of the 7.5 thousand million cork stoppers used annually throughout the world are produced in Portugal by manual methods that have not changed for many years. At a time when labour costs in Portugal are approaching those in other EC countries and when impending EC safety regulations will shortly make current manufacturing methods unlawful, there is an urgent need to modernise the industry. This paper describes the further development by the authors of a low-cost vision system that enables a machine to manufacture cork stoppers automatically. The vision system, which uses six monochrome CCD cameras and a solid-state laser, is capable of generating a punching pattern optimised to make best use of the raw cork material. The vision system allows objective quality control constraints to be applied and decreases the amount of waste produced when compared with the manual method. A fully functioning prototype of the machine has been built and successfully tested