A knowledge-based system for process-sequence design in axisymmetric sheet-metal forming

Abstract

A hybrid Computer-Aided Engineering (CAE) system for automatic process-sequence design for the manufacture of axisymmetric sheet-metal components has been developed. The input to the CAE system is the final sheet-metal object geometry that needs to be manufactured, and the output from the system is the process sequence with intermediate object geometries. Two main components of the hybrid CAE system are a knowledge-based expert-system module (symbolic module) and a process-modeling analysis module (numeric module). The knowledge-based system module will first generate an initial-guess process sequence based on experience-based die-design guidelines, and this process sequence will then be tested for defects and failures by mathematically modeling the sheet-metal forming process using the analysis module. The analysis module will formulate mechanics of metal forming and predict stresses and strains in the deformed geometry and punch load versus displacement. This paper describes the knowledge-based system and compares process sequences outputted by the system with corresponding process sequences from industrial practice. It was found through several test cases that the blank diameter and the number of stations suggested by the knowledge-based system compare well with those used in industrial practice.