KBE Application for the Design and Manufacture of HSM Fixtures

摘要

The design of machining fixtures for aeronautical parts is strongly based in the knowledge of the fixture designer, and it comprises certain repetitive tasks. An analysis of the design process allows us to state its suitability for developing Knowledge Based Engineering (KBE) applications in order to capture the knowledge, and to systematize and automate the designs. This work justifies the importance of fixtures for High Speed Milling (HSM), and explains the development of a KBE application to automate the design and manufacturing of such elements. The application is the outcome of a project carried out in collaboration with the company EADS. In the development process, a specific methodology was used in order to represent the knowledge in a semi-structured way and to document the information needed to define the system. The developed KBE application is independent of the parts design system. This makes it necessary to use an interface to input the part geometry into the KBE application, where it is analyzed in order to extract the relevant information for the fixture design process. The results obtained from the application come in three different ways: raw material drawings, fixture 3D solid models, and text files (Bill Of Materials - BOM, and Numerical Control - NC programs). All the results are exported to other applications for use in other tasks. The designer interacts with the application through an ad hoc interface, where he is asked to select or input some data and where the results are also visualized. The prototype KBE application has been carried out in the ICAD development environment and the main interface is with the CAD/CAM system CATIA V4.