Feature Information Extraction And Reconstruction Of The Rotor Model Based On Step Neutral File

International standards STEP is a international standards about the product in its processthroughout the life of the product data representation and exchange, the purpose is to providea neutral and not depends on the specific system mechanism, able to describe the entire lifecycle of the product data and maintain data consistency and integrity. In this paper, against therotor parts, understand the STEP neutral exchange file, detailed analysis and research STEPstandard and its structure. Extract three-dimensional geometric information which the STEPneutral exchange file extracted, after extracted feature information, reconstructOpenGL-based platform for its3D model. The contents and results are as follows:1. EXPRESS language and C++language mapping. STEP standard contains manyapplication protocols, this paper, for the three-dimensional shape of the product design, mainresearch application protocol AP203(3D product definition set), and related integratedresources; research STEP standard, learn EXPRESS formal description language; follow theAP203application protocol, establish mapping between a three-dimensional geometricentities EXPRESS and language C++language, and establish C++classes for each entity.2. STEP application protocol-based design of the lexical analyzer. According to theprinciple of STEP application protocol entity of the expression to design the STEP lexicalanalyzer. The lexical analyzer can finish read in of STEP neutral, extracting entityinformation, entity object instantiation and other function. We need to design flow chart ofthe program, algorithm and program for STEP lexical analyzer of the each module, throughthe use of C++language programming to complete the extraction of entity STEP neutral fileinformation.3. Based on the characteristics information of the STEP neutral exchange file extractmethod design. STEP neutral exchange file is based on the AP203application protocol, STEPneutral file is through solid mutual references describes product geometric entity, throughmutual reference between entities plus correlation operator, it complete description of productinformation. This paper studied STEP neutral file structure, the expression of solid information and lexical description format, complete the design of algorithm for featureinformation extraction based on STEP neutral exchange file, then studied and analyzed thefeature recognition technology, and then complete the information extraction, laid thefoundation for the model reconstruction and display of the3D geometry features.4. OpenGL-based3D geometric solid model reconstruction. Study on OpenGL3Dmodeling platform, according to the extracted3D geometry information, with OpenGLtechnology to draw the3D entity. Study on the application of OpenGL3D graphic library inthe middle of the three-dimensional entity model. In the Visual C++platform, by thecorresponding a certain way calls the corresponding function in the OpenGL dynamic linklibrary, realize the reconstruction of the3D geometric entities model in STEP data model.