【作者】 马淑梅；

【导师】 李爱平；

【作者基本信息】 同济大学 ， 机械制造及其自动化， 2006， 博士

【摘要】 在经济全球化时代，任何企业所能拥有的产品竞争优势都是相对的、暂时的，除非持之以恒地创新。因此，不断开发新产品是企业最重要的任务，也应该成为我国学者的研究热点。作为产品快速开发的重要支撑技术集成逆向工程技术，其研究和应用的成果对解决与之相关的产品快速开发问题具有一定的指导作用。本文针对STL模型的快速建模、模型综合优化及重构模型的再设计等集成逆向工程中的主要关键技术进行了深入研究。 主要研究工作及成果归纳如下： (1)针对产品快速开发的需求，建立了集成逆向工程系统的体系结构。全面、系统地总结和分析了集成逆向工程系统各环节上的现有方法和技术难点，内容贯穿了从数据获取到产品制造的整个过程，促进了集成逆向工程系统中目前仍需要解决的问题和待完善的技术研究，为本文研究方向的确定奠定了基础。提出了针对离散数据，采用模仿式的创新设计方式和基于STL模型的RE／RP系统直接集成的方法，推进和丰富了产品快速开发关键技术的研究。 (2)针对离散数据输入数据组织形式，开发了基于离散数据的STL模型的快速建模的算法。从算法的时间效率性，适应性和处理对象的复杂性等角度出发，采用将3D离散数据投影到某一平面的方法，把一个3D三角划分问题转化成平面上不规则点的三角划分问题，并使用凸壳来减少计算时间，在三角网格的划分过程中同时实现最小权优化，从而避免了三角网格完全生成后再进行优化和调整的反复过程，提高了时间效率性，降低了算法的复杂性。该算法能够有效地处理各种不同类型曲面的离散数据，且实现过程简单，弥补了现有商业CAD的不足，使得算法具有很强的适应性，为基于STL模型的模仿式创新设计提供了及时有效的技术支持，是产品快速开发中模型创新设计的关键环节。 (3)针对环域网格划分的特点，提出了STL模型综合优化的概念，并研究了其算法实现。在将传统的最小角最大化和最小权这两种优化方法相结合，进行全局初始优化的基础上，提出增加顶点删除法这种综合改良方法。通过增加合适的网格顶点，删除退化的几何要素，生成新的几何要素，并对网格中拓扑关系发生改变的相应几何要素进行实时地更新，更为主动地优化三角形形状。解决了优化过程中出现的退化现象和局域狭长三角形比较集中现象，并将网格更多还原

【Abstract】 In the times of economy globalization, nothing could help one company or enterprise to hold constant advantage over others, but temporary and relative, except for innovation. So, keeping on development on new products has become the main task for corporations, which should be the hot spot for academic research in China. As the important support technology in the rapid product development, the research and application of the integrated reverse engineering help to solve the related problems. The key technology of the integrated reverse engineering are studied deeply. They are modeling STL model rapidly, model integrated optimization and re-constructed model re-designing technology.The main research works and results in this paper are summed up as follows:(1) Aiming at the requirement of rapid product development, the integrated reverse engineering system frame is founded. Problems need to be solved and technology need to be completed in the current integrated reverse engineering system are educed after made comprehensive and systematic summery and analysis of the current methods and key technology in the reverse engineering, which go through all the procedures from data acquisition to product finishing, all of which set the foundation of research orientation. Model innovative design methods for handling discrete data and solution to directly realize integration of RE/RP based STL model are presented. These results promote the research of rapid product development, and help to solve some key problems.(2) Aiming at the input organization order of discrete data, the algorithm of modeling STL model rapidly based on discrete data is exploited. Time efficiency of algorithm, adaptation, complex of objects, projecting 3D discrete data to a certain plane, with which to transfer 3D triangular mesh into mesh of disordered spots in one plane, meanwhile reduce time by means of bulge shell is presented. To apply bulge shell method can efficiently reduce time of mesh in the selected area, enhance mesh speed, meanwhile realize minimum weight so as to avoid repeat optimization and更多还原