快速成型过程中精度控制及其传递规律的研究-材料加工工程专业论文.docxVIP

武汉理T=：^：=学域，l：学位论文摘要 武汉理T=：^：=学域，l：学位论文 摘要 本文在全面分析和总结目前快速原型制造技术(R刚)国内外发展现 状及应用的基础上，针对快速原型制造技术存在的问题，对快速成型过程 中影响快速成型制品精度的关键技术进行了研究和探讨。 首先从STL转化过程中误差产生的原因着手，找到表面网格化处理这 个因素会对精度产生影响，结合具有代表性的三维造型软件，对转化过程 中控制参数(弦高)进行优化，得到既能满足三维实体精度要求，又不需 要占用太多时间、空间等情况下的最佳弦高选用值。 通过分析STL转化过程中三角形面片之间的几何连续性，应用其连续 性，使得各个三角形之间建立一种索引关系。在读入STL文件时．通过面、 边、点的拓扑信息，可分析STL文件缺陷，利用相关软件进行修复，可以 显著降低内存占用量，加快拓扑信息提取时间，提高STL转化精度。 通过对LOM快速成形系统及其制件精度的分析，研究了数字模型一快 速原型之间的精度传递规律，提出对数字模型的修改方案，并利用研究所 得精度传递规律，进行实验验证。 关键词：快速原型制造 STL数据模型 数据处理 精度控制 武汉理工大学硕士学位论文Abstract 武汉理工大学硕士学位论文 Abstract Based on a full—scale analysis and summary for the development status in quo and the application of Rapid PrototypingManufacturing nationally and intemationally,the key technology which has effect 011 the precision of products in RP process is researched and probed into according to problems existed in RPM technology． The paper set about from the reason of error produced in the course of transferring CAD model to STL files．It is found out that surface-meshing process has important effect on precision which results in the emergence of errors．By combining with using typical three—dimensional paint software，the control parameter in transferring process，namel y the Chord Height，is optimized．n屺optimal Chord Height parameter is found by which the entity can be described more accurately．It also takes less time and EMS memory to deal with． Geometry continuity of the triangular facets is analyzed in the course of generating STL files．The index relation is built up between every triangular facet by making use of this continuity．The disfigurements existed in STL files can be analyzed if topology information among facets，sides and points is utilized when reading STL files．If repaired by using relative software，it will take less time and EMS memory to process datum and improve the precision in process oftransferring CAD model to STL files． The precision of product made by the LOM rapid prototyping system is analyzed in this paper．The law of precis