A Methodology to Support Robotic Polishing of Molds Integrated with CAD/CAM

Abstract

Typically, the final process in the manufacture of molds is mechanical polishing, a process predominantly conducted manually. This is an important process step to improve the surface quality of the mold without affecting the geometry of the cavity. Currently, the European mold manufacturing industry faces two challenges for the polishing phase of manufacture. Firstly, economics when compared to global low-cost production areas. Secondly, the industry is starting to suffer the loss of skilled benchmen specialized in performing such operations. To address these two problems, robotic polishing has been investigated as an alternative or supplement to the conventional manual polishing process in the manufacturing of molds because of its high efficiency, improved reliability, and robustness. This paper presented a new methodology that allows robotic polishing to replace majority of manual polishing work for the manufacture of molds and achieves complete information integration with current CAD/CAM systems. Based on a number of experimental works, the types of features that are suitable for robotic polishing have been identified and a new robotic polishing feature classification has been proposed. A new polishing process planning has been developed to be integrated with current CAD/CAM systems, which includes a robotic polishing process knowledge database; a polishing process selection method; and a polishing process sequencing using genetic algorithm aiming to combine minimum polishing time and the specific constraints and rules for polishing process sequencing. Finally, a case study based on the proposed methods has been given, which demonstrates the proposed methodology is able to be implemented in the practical environment to allow robotic polishing to take majority of manual polishing workloads for mold manufacturing and achieve information integration with current CAD/CAM systems.