On Tolerance Information Extraction of Feature Model in Automotive Engine CAPP System

A generative automotive engine CAPP (Computer-Aided-Process Planning) system based on Oracle database was developed. A practical tolerance information communication solution between the CAD and CAPP system was proposed and realized in an independent file schema. A parametrical cylinder head model based on manufacturing feature was created to meet the requirements of the CAPP system feature recognizing. The data structure of the tolerance information in the Pro/ENGINEERING database was presented. A Pro/TOOLKIT program was developed to extract the model’s tolerance information automatically. The tolerance information extracted was then organized with EXPRESS language and imported into the CAPP system database Oracle.