汽车车身覆盖件逆向工程技术

机械论文编号:JX860  论文字数:15231.页数:37   附图

 目  录
中文摘要 i
英文摘要 ii
目录 iii
第一章     绪论 1
1.1   本课题研究背景 1
1.2   逆向工程介绍 2
1.3   逆向工程发展状况 3
第二章    逆向工程开发与设计 4
2.1   逆向工程四个过程 4
2.2   逆向工程常用软件 4
2.3   逆向工程中常用的测量方法 5
2.4   测量机盖板点云数据 7
2.5   IMAGEWARE 调点云 7
第三章     CATIA V5 软件介绍 8
      3.1   CATIA V5 简单介绍 8
      3.2   CATIA V5基础 8
      3.3   零件设计 10
      3.4   创成式曲面设计 11
第四章     三维建模 13
      4.1   点云 13
      4.2   坐标系的建立 16
       4.3   三维建模 19
         4.3.1  曲线拟合造型 19
         4.3.2  曲线插值过程 21
      4.4   建立外板的曲面  22
       4.5   曲面直接拟合 25
      4.6   曲面重构的特点 30
       4.7   三维出模 31
第五章    总结  32
致谢 33
参考文献 34
 三维图（另附）

摘要
    在20世纪90年代，国际汽车界兴起一种逆向工程的汽车产品开发新方式。经过几年的发展，积累了很多经验，取得巨大进步，可以说已成为现代汽车产品开发的主流形式。
 本文首先介绍下逆向的四个过程和所用的CATIA软件，对CATIA软件的两个重要模块有所了解。以车前盖板逆向工程设计为例主要以CATIA软件为平台建模的实例来说明逆向的整个过程。用三维测量机测得三维数据，形成点云并网格化。根据网格后的大面或局部特征建立适当的三维坐标，在快速成形模块，拉成大的面。选取点云的边线，拉升相交面，相交减，形成外轮廓线。用这种方法完成一个车前盖板的三维模型。
    实施逆向工程的目的是为了更好地实现汽车产品设计的并行工程，使产品设计与其它相关过程实行同步作业，并使之优化，大大提高产品设计的一次成功率，从而缩短周期，降低成本，减少风险，提高质量，增强企业竞争力。
 逆向工程不仅仅是反制的过程，更是一个学习与交流的平台。中国的汽车制造业起步相对来说比较晚，与发达的国家比起来有一点的差距，根据实际情况说明逆向工程对我国汽车设计方向有指导性的意义。
 
关键词：逆向工程  车前盖板  点云采集   三维建模
                         
 
 
 
　 Auto body reverse engineering
 Abstract
 In the 1990s, the international automobile industry develop a new way which is named reverse engineering of automotive products . After several years of development,accumulated a lot of experience and achieved tremendous progress, it can be said the method has become the mainstream form of product development.
 This article first introduces the four process of reverse and the use of CATIA software which has two important models. As an example,the front cover of reverse engineering design,it is used to illustrate reverse during the whole process.We use three-dimensional measuring machines to get the data. And then it is form of cloud formation and grid.According to the grid and features，we can establish an appropriate three-dimensional coordinates and form a big surface. Select the point cloud the lines and then elevate intersection face.After the intersection,it forms the outline of the product. In this way, the establishment of three-dimensional model is founded.
    The implementation of reverse engineering is designed to better concurrent engineering .In order to enhance the success rate and reduce the cost, you should keep all the steps at the same time.If you put it in practice, you can shorten the cycle of product and increase the competitiveness of enterprises.
 Reverse engineering is not only get the objects,but also it is a learning and communication platform. Automobile manufacturing industry in China starts relatively lately compared with the developed countries. According to the actual situation , reverse engineering in the design leads the direction.
Keywords:   Reverse engineering  The front cover of car   Point acquisition   Three-dimensional modeling