An intelligent software system for the automatic generation of NC programs from wireframe models of 2-1/2D mechanical parts

Abstract

The aim of this work is to generate automatically NC part programs for machined components of 2-1/2 dimensions starting from a wireframe CAD model. An IGES post-processor was developed to interface the system to any CAD system, then a conversion program sought to obtain solid modelling geometry from the wireframe model. Subsequently, drawing annotation information was allocated to solid model entities through pattern matching techniques in Prolog. The product model was completed by deriving feature instances according to pre-defined feature templates constructed in Prolog according to a simple model. Operation selection uses the feature model as well as process planning knowledge structured into a hierarchy of Prolog rules processed by a context sensitive inference engine. The resulting operation sequence is communicated to a module that calculates cutting conditions and produces NC code. The system was proved to work satisfactorily with components of an industrial standard.