共查询到10条相似文献,搜索用时 281 毫秒
1.
STL实体模型的拓扑重建及其缺陷修复 总被引:6,自引:0,他引:6
STL文件是CAD系统与快速成型制造系统之间进行数据交换的标准格式文件,由于CAD系统在生成STL文件时使用的转换方法不当,使得由STL文件描述的实体模型有许多缺陷,要修复缺陷建立实体模型的拓扑关系是必要的。该文首先对STL实体模型进行了拓扑关系重建,然后修复了一些实体模型中常见的缺陷。 相似文献
2.
Chung-Shing Wang Author Vitae Wei-Hua A. Wang Author Vitae Author Vitae 《Computers in Industry》2010,61(3):187-197
This paper presents a simple process to construct 3D rapid prototyping (RP) physical models for computer tomography (CT) medical images segmentation. The use of stereolithography (STL) triangular meshes as a basis for RP construction facilitates the simplification of the process of converting CT images to an RP model. This is achieved by constructing the STL triangular meshes directly from data points without having to draw the curve model first. The grey prediction algorithm is used to sort contour point data in each layer of the medical image. The contour difference detection operation is used to sequence the points for each layer. The 3D STL meshes are then constructed by this proposed layer-by-layer sequence meshes algorithm to build the STL file. Once this STL file is saved, a 3D physical model of the medical image can be fabricated by RP manufacturing, and its virtual reality model can also be presented for visualization. CT images of a human skull and femur bone were used as the case studies for the construction of the 3D solid model with medical images. The STL models generated using this new methodology were compared to commercial computer-aided design (CAD) models. The results of this comparative analysis show that this new methodology is statistically comparable to that of the CAD software. The results of this research are therefore clinically reliable in reconstructing 3D bio-CAD models for CT medical images. 相似文献
3.
由于STL文件格式的容易生成且不需要复杂的CAD系统支持,已经发展成为快速成型制造领域数据交换的准标准;但是STL模型的精度与其数据文件的尺寸之间存在严重的矛盾,为了在较小的STL文件下得到较高的轮廓精度,本文提出了一种基于三次NURBS曲线STL模型截面轮廓的重构技术,通过设置直线阈值和转角阈值的方法,分段拟合STL截面轮廓数据,使其截面轮廓具有更好的平滑度和更高的精度。 相似文献
4.
5.
Because of the differences in the nature of rapid prototyping (RP) processes, there is no standard machine path code for them. Each RP process, based on its characteristics and requirements, uses the standard CAD file format to extract the required data for the process. Selective inhibition of sintering (SIS) is a new layered fabrication method based on powder sintering. Like other RP systems, SIS needs a specialized machine path generator to create an appropriate machine path file. Machine path (i.e., boundary path and hatch path) should produce the printing pattern that enables the SIS machine user to easily remove the fabricated part from the surrounding material. A new machine path algorithm, which generates appropriate boundary and hatch paths for the SIS process is proposed. The new machine path generator provides the ability to process CAD models of any size and complexity, the ability for machine path verification before sending the file to the SIS machine, and the ability to fix the possible STL files disconnection errors. In this system, very large STL files can be processed in a relatively small computer memory. The system has been successfully tested on STL files as large as 200 MB. The generated path files have been used in fabrication of several parts by the SIS process. 相似文献
6.
STL数据检验和修复 总被引:2,自引:0,他引:2
STL数据文件是快速成型最常用的数据交换文件,STL数据的错误将影响快速成型预处理的进行.本文提出一种STL数据检验和修复算法,它通过对STL数据建立拓扑关系,依据棱与面的关联度快速捕获STL数据的错误.针对不同的STL数据错误采用相应的算法,对STL数据进行有效的修复. 相似文献
7.
8.
STL(stereo lithography)作为3D扫描数据和快速原型制造事实上的标准,其广泛应用于娱乐、制造业和Internet等领域.但随着3D模型越来越复杂,数据量越来越庞大,从STL文件难以快速获得完整拓扑关系以及其存在大量冗余信息的缺点,制约着STL网格模型的进一步优化处理与应用.为此,需要针对STL网格模型进行网格重建.本文针对2维流形的STL三角形曲面网格模型,提出了一种快速的网格重建方法.主要利用删除在重建过程中达到饱和的顶点,以便减少需要比对的顶点数,并结合STL文件数据的相关性来提高顶点搜索与比较的效率.对于非封闭的曲面网格,本文算法在提高曲面网格重建效率的同时,还能有效地提取曲面网格模型的边界信息.另外,重建的曲面网格数据文件大大地减少了存储空间,有效地去除了冗余数据.实验结果表明本文算法的高效性及鲁棒性. 相似文献
9.
快速成型技术在医学领域有着广泛而重要的应用,为了从医学图像中得到快速成型文件,详细论述了MC(marchingcubes)算法生成STL文件的步骤及需要注意的问题,并将其与轮廓连接生成STL文件的方法进行比较,说明了所提方法优势及可行性。方法先对CT序列图像进行阈值分割、区域增长等图像预处理,然后用MC算法得到用三角片组成的几何模型,最后根据文件格式标准,生成STL文件,其中着重讨论了STL文件中三角面片顶点顺序如何确定这一问题。 相似文献
10.
CAD/CAM技术在脚医学中的应用 总被引:1,自引:0,他引:1
将CAD/CAM技术与脚医学结合,研究开发脚支撑设计制造系统,包括脚底曲面数据的读取及处理,根据医疗规划完成三维脚支撑模型的构造,平衡及光滑处理,激光快速原型文件和铣削加工刀具轨迹的自动生成等。 相似文献