【作者】 张胜文；

【导师】 王贵成；

【作者基本信息】 江苏大学 ， 机械制造及其自动化， 2013， 博士

【摘要】 随着制造科学与技术发展,CAD/CAPP/CAM集成技术研究及应用不断深入,但是由于CAD、CAPP、CAM三者之间缺少统一的数据模型,系统的复杂性和产品对象的特殊性,目前尚没有一种方法能够系统地解决船用柴油机复杂零件CAD/CAPP/CAM集成问题。因此,本研究针对船用柴油机复杂零件生产企业的实际需求,对CAD/CAPP/CAM系统集成的关键技术问题开展研究,探索一种有效的CAD/CAPP/CAM集成方法,实现了船用柴油机复杂零件CAD/CAPP/CAM系统集成。论文主要研究工作及取得的成果如下：(1)基于船用柴油机行业对CAD/CAPP/CAM集成技术的需求,按照CAD/CAPP/CAM系统各个子功能的特性及要求并按照模块化设计的思想对系统进行了总体规划,提出了集成系统的体系结构,给出了系统开发的原则与开发流程。(2)对特征技术、STEP技术和MBD技术等在CAPP系统中应用的关键技术,以及基于图论的特征匹配方法进行重点研究的基础上,提出了特征多项式理论在特征匹配算法中应用的新方法,实现了已有算法的时间复杂度改进。运用“特征命名法”通过STEP中性文件实现了箱体类复杂零件中需要加工的特征儿何信息提取。并描述了特征重构的思想、方法与流程,借助于特征重构技术构建了加工特征数据库。(3)以箱体类复杂零件中的平面、孔加工特征为例阐述了基于特征的工艺推理方法,提出了运用n维向量内积夹角余弦算法进行工步排序的方法,该算法在复杂零件工步排序领域应用具有更加完备的数学理论基础、严格意义上的全局优化性以及收敛稳定性。应用模糊理论、权重决策理论等对刀具优选的关键技术开展了研究,用惩罚函数法结合模糊理论等知识进行了切削参数优化,为集成化CAPP系统提供了切削刀具的优化选择及切削参数的推荐。(4)从基于MBD技术构建加工工艺信息与建模信息映射出发,提出了三维工序模型逆向生成的方法,通过建立加工方法与建模操作组之间的二元关系与转换关系,使工艺人员能面向零件的工艺方法创建三维工序模型,减少了设计过程中的重复性劳动,对于实现数字化三维工序模型快速生成具有重要的参考价值。(5)针对船用柴油机复杂零件和企业数控加工设备的特点,探索了成组技术与知识工程技术在智能数控编程系统中的应用,对基于特征的船用柴油机复杂零件刀具轨迹规划与优化方法、基于UG NX平台的CAD、CAPP、CAM集成方法开展了研究,利用UG NX平台的二次开发技术开发了智能化船用柴油机复杂零件CAD/CAPP/CAM集成系统。以VERICUT软件为平台,构建了虚拟数控加工仿真平台,并在企业生产中进行了船用柴油机复杂零件数控加工程序的可靠性和有效性验证。更多还原

【Abstract】 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.更多还原