An integrated CAD system for the blanking of irregular-shaped sheet metal products

Abstract

Abstract This paper describes research work into developing computer-aided design for the blanking and piercing of irregularly-shaped sheet metal products. This approach to an integrated CAD system is based on knowledge-based rules. Knowledge for the CAD system is formulated from plasticity theories, experimental results and the empirical knowledge of field experts. The system has been written in Auto LISP on the AutoCAD system with a personal computer. The system is composed of six main modules: input and shape treatment, production feasibility check, blank layout, strip layout, die layout and drawing edit module. Based on the knowledge-based rules, the system, STRTDES1, is designed by considering several factors, such as the complexities of the blank geometry and the punch profiles and the availability of press equipment and standard parts. This system can therefore carry out a die design for each process that is obtained from the results of an automated process-planning system and generate part drawings and the assembly drawing of the die set in graphic form. The developed system provides powerful capabilities for the process planning and dies design of irregularly-shaped products.