Research On The Key Technology Of The CAD/CAPP/CAM Integration For Complicated Parts In The Marine Diesel

With the development of manufacturing science and technology, the CAD/CAPP/CAM integration technology research is unceasingly thorough. However, there has been no method which can fundamentally solve the problem of CAD/CAPP/CAM integration due to lack of unit data model among CAD, CAPP, CAM, the difference of the unit technology development level, the complexity of the system and the particularity of product objects, therefore, based on the complex marine diesel engine parts plants’true demand, an effective method for CAD/CAPP/CAM integration was explored, and a set of practical software about the complex marine diesel engine parts was also developed. The main results are as follows:(1)The complex marine diesel engine parts’CAD/CAPP/CAM integration system architecture was proposed based on the demand for CAD/CAPP/CAM technology in marine diesel engine industry, in accordance with each function’s symbol and demand of CAD/CAPP/CAM system, and the modular design thinking system for the overall planning. Given the principles and the development process of system development, the integrated system development platform and development tools were chosen.(2) The new method of application of characteristic polynomial theory in the feature matching algorithm was proposed on the basis of research on application of CAPP system of characteristics technology, the STEP technology and model-based definition technology, as well as the feature matching method from graph theory, the algorithm time complexity has been reduced compared to the existing algorithm. Information extraction for machining characteristics was realized by applying the "Feature Naming Method" through STEP neutral file implements. And the thought of characteristics of the reconstruction, the method and process is described with the aid of features reconstruction technology to build the processing characteristics of the database.(3) The feature-based process reasoning method is expounded by using the instance of the plane and hole drilling features of the complicated parts for the box-type parts. A method for box part working steps’sequence which used the n-dimensional vector inner product cosine of the angle algorithm was proposed. The analysis of the algorithm processes shows that the algorithm has more intact mathematical theory and strict sense of the global optimization and convergent stability.The penalty function method combined fuzzy theory was used to optimize the cutting parameters. Accordingly, combining the fuzzy theory and the weight of decision theory, the research was done in key technologies about the tool preference. All of these works had provided technical support for the integration of the CAPP system development.(4) Based on the processing information of the MBD-based technology for building process and modeling, the reverse-generated three-dimensional process model was developed, through the establishment of a binary relation between the processing methods and modeling operations group conversion, the three-dimensional process model can be created by using the process-oriented method. This method reduced the duplication of effort in the design process. It has an important reference value in the achievement of digital three-dimensional process model.(5) Aiming at the complex marine diesel engine components and the characteristics of firm CNC processing equipment, research has been done on the method of marine diesel engine tool path planning and optimization of complex parts by features. Based on the corresponding form of tool path, the machining features of complex marine diesel engine parts are classified. Based on its corresponding form of tool path, the intelligent NC automatic programming system has been developed. Preliminary exploration about the CAD/CAPP/CAM integration system implementation technologies of complex parts of marine diesel engine has been done based on the technology of MBD. The CAD、 CAPP、CAM integration method and technology based on the UG platform and the technology of building broad knowledge are studied in depth. Using the secondary development of UG platform technology, the CAD/CAPP/CAM integrated system of complex parts of marine diesel engine was developed. Using VERICUT software, virtual NC machining simulation platform was constructed to complete the integration system of marine diesel engine for the reliability and validity of the NC program verification.