A true generative CAPP system for DFM application to machined components

Abstract

Today's highly competitive marketplaces require production systems that are flexible and responsive to changing demands. To remain competitive, companies need close coordination and exchange of computer interpretable information between product design and the manufacturing system. Computer-Aided Process Planning (CAPP) is an essential key for achieving closer links among design and manufacturing activities.

The purpose of process planning is to generate feasible sequences for producing a part in a given production facility. To generate process plans automatically (true generative CAPP), design information along with production facility information needs to be appropriately represented. Most CAPP systems assume feasible designs as input and lack the capability to evaluate designs for manufacturability with respect to the production facility. The objective of this research is to develop a true generative CAPP system that is an integral part of a design for manufacturability (DFM) application for machined components. It involves determining appropriate representation schemes of machined components and production facility resources.

The created CAPP Module, developed using C++, consists of five process dependent modules for automatic process plan generation and evaluation: (1) Process selection, (2) Machine/Tool Selection, (3) Setup/Fixture Planning, (4) Operation Sequence Planning, and (5) Process Plan Evaluation. Process plan generation is performed by the first four modules. Evaluation of process plans is performed by the Process Plan Evaluation Module. Criteria such as cost, resource utilization, and production requirement, are used to generate the most appropriate process plan and to select additional process plans as needed.