A knowledge-based approach to automated machining process selection and sequencing

This paper describes an expert module for automatic process selection and sequencing. This process selection and sequencing algorithm comprises three sub-algorithms, the transformation algorithm, the refinement algorithm and the linearization algorithm. The module is a part of a prototype expert process planning system for the machining of prismatic parts. In this prototype CAPP system, both the part description and the operation sequence are represented by a tree structure. To generate the process sequence for a given part, an operation tree is converted from the geometric description in the transformation algorithm and this tree will then be refined and then linearized to the final process sequence. The system is equipped with a sequence knowledge-base which records various types of information including the process capabilities, filling knowledge, surface priority, surface knowledge, refinement knowledge, and linearizing strategy.