【作者】 黄焕江；

【导师】 郭钢；

【作者基本信息】 重庆大学 ， 机械制造及其自动化， 2003， 硕士

【摘要】 随着全球一体化的不断发展和加入WTO后市场竞争的加剧，如何将先进的理论、方法与数字化信息技术应用于我国汽车开发的实践中，使我国汽车公司在技术引进、消化吸收和积累后建立具有自主知识产权和较强市场竞争能力的企业核心技术和开发平台，实现自主创新与发展，逐步摆脱在技术上受制于国外汽车公司和创新能力低下的困境，尽快缩短与发达国家汽车工业的差距，就显得特别重要和迫切。为此，本文围绕汽车开发的关键部分——汽车覆盖件进行展开，研究了汽车覆盖件的三维重构与工艺分析的相关理论和方法。首先通过分析汽车覆盖件的三维重构与工艺分析的研究现状和存在的不足，提出了本文所要研究和解决的主要问题。同时，阐述了汽车覆盖件与三维重构的内涵和特点、研究三维重构的必要性以及本文研究的目的和意义。然后，在计算机图形学和计算机辅助几何设计等理论的基础上，根据汽车覆盖件的特点，归纳总结了适用于汽车覆盖件三维形体几何表达的相关理论和经验；研究了构成汽车覆盖件曲面的典型曲面构造方法，重构曲面的光顺品质分析、误差分析与曲面品质优化的方法，三维重构模型的“半”边数据结构、不同冲压工序中的数据演化以及不同软件平台之间的数据交换；提出了根据周边曲面的形状特点构造交汇曲面的方法。同时，在上述基础理论的支持下，重点研究了汽车覆盖件三维重构的关键技术，主要包括：在分析工程图、实物或模具、电子信息和设计思维四种重构数据源及其特点的基础上，提出了基于不同数据源的三维重构的方法与流程；研究了曲面分割与拼接技术、复杂曲面的倒圆技术及难点解决方案；研究并建立了汽车覆盖件三维数学模型的设计规范与技术要求以及基于正向设计和三维重构设计思路的汽车覆盖件的开发流程基本框架；提出并研究了基于二维工程图与模具型面点云的曲面重构流程和数据处理方法。接着，在分析汽车覆盖件的基本冲压工序特点、成形性和产生拉深起皱、破裂与回弹缺陷的原因及应对措施的基础上，通过对汽车覆盖件的拉深成形工艺模型的建立与质量评估以及典型工艺分析方法的讨论，结合汽车覆盖件设计所考虑的因素，研究了工艺分析对汽车覆盖件设计的影响，部分验证了汽车覆盖件的三维重构设计的质量，总结并提出了集成有限元（FEM）模拟的汽车覆盖件设计方法。最后，将上述系统理论与方法成功地应用于某合资汽车公司对某型轿车实施数字化样机技术的实践，圆满地完成了所承担的科研项目，获得了该公司的好评更多还原

【Abstract】 With the development of the integrative world and increasingly competitive market after entering WTO, it looks specially important and urgent how to use the advanced theory, methods and digital information technology to establish the core technology and development platform with independent knowledge property right and market competitive power by introducing into, assimilating and accumulating the foreign technology, so as to realize independent innovation and development, gradually walk out of the plight of being restricted by the foreign companies in technology and the lower innovative ability, and shorten the gap of auto industry between the developed countries and China as quickly as possible. Therefore, as the key part of auto-body, the panels are researched about the related theory and methods of reconstruction and processes analysis, which is nuclear in this thesis. Firstly, on the basis of analyzing research status and shortage about 3D reconstruction and process analysis of automobile panels, the main research contents of this thesis are proposed. And the definitions and traits of automobile panels and 3D reconstruction, research reasons of 3D reconstruction and the purpose and learned significance of this thesis are set forth.Secondly, based on the theories of computer graphics and computer aided geometric design, and according to the traits of automobile panels, the related theory and experience about 3D geometric expressing of automobile panels are described. It is studied to the constitution methods of typical surfaces forming the surfaces of automobile panel, fairing quality and error analysis and optimization of reconstruction surfaces, and the storage structure of ’half’ edge for 3D model, data changes in different stamping steps and data exchange among the different software. The constitution methods of converged surface based on the shape of around surfaces are proposed. Meanwhile, the key technologies of 3D reconstruction for automobile panels are especially researched, which includes: after analyzing four data sources, which are engineering drawings, product, electric information and design thought, of reconstruction and their characteristics, the methods and flows of 3D reconstruction based on the different data sources are proposed; studied the technology of surface segmentation and splicing and blending of complicate surfaces and the difficult cases; the design criteria and specifications of 3D model and the basic framework of designing<WP=6>based on the forward and 3D reconstruction design idea for automobile panels are also established and studied; and the flow of surface reconstruction and the methods of data process based on engineering drawings and point cloud of die surface is put forward and researched.Thirdly, after analyzing the characteristics of basic stamping steps, formability and the reasons and precautionary measures of stamping defects about automobile panels, such as wrinkle, crack, spring back and so on, and by discussing the establishing process and quality evaluation of process models and the typical methods of process analysis of automobile panels, the influence of process analysis on automobile panels design is studied, which combines the factors of automobile panels design. The quality of 3D reconstruction design is also partly validated. And design method integrated FEM simulation for the panels is summarized and proposed.Lastly, the above systematic theory and methods are successfully applied for the virtual prototype technology for a car in a joint-stock motor company, and many good remarks are got更多还原