Research And Realization Of The STEP-NC Interpreter

STEP-NC(ISO14649)expends STEP into the area of CNC and renews the data interface between CAX and CNC, which helps CNC system to use data models of products in three dimensions according with STEP directly in order to output NC programs then control machines directly, eliminate choke points of the information stream between CAX, such as CAD, CAPP, CAM, CAE, PED, ERP and so on, connect the design product information and manufacturing product information on the base of STEP in the form of object-orientation, and change the traditional movement and switch control-orientation numerical programs into object-orientation programs.STEP has been applied into CAD/CAM systems, so STEP-NC makes information bidirectional between CNC and other CAX systems; the richer information in the program files raises the level of intelligent functions of CNC.The main features, the contents and structure, file formats and the direction of development of STEP-NC are summarized respectively on the basis of analyzing the shortcomings of ISO6983. All data types defined in the description language EXPRESS of STEP-NC are summed up and the mapping rules from EXPRESS to C++ language are given. Then functional architecture and main features of three STEP-NC translators are analyzed.According to the order of running, the system is divided into four parts, collecting information and identifying features, generating tool travel-paths, showing programs and examining file syntaxes. The system takes compound feature, replicate feature, profile feature, slot feature, step feature and chamfer for example in order to analyze the design process. The key technology of the implementation of each functional module involves a lot of things, including code of program and the algorithms and the flow charts.In the last, the software appearance is shown, which shows the main information included in the STEP-NC files, NC programs and the error information, then the output files is operated on the HIT-CNC milling machine and examines the feasibility of the translator.Thanks to the resources of the Document/View framework of MFC, the...