一种避免轮廓相交的STL模型快速切片方法

A rapid slicing method for STL model to avoid contour intersection

为提高3D打印对STL三角网格模型分层切片的效率和准确性,提出一种避免轮廓相交的切片处理方法。首先建立模型与切平面相交的三角片集合,然后获取相交三角片与切平面的交点,并将交点映射为无向加权图,最后利用深度优先搜索算法交点进行拓扑排序,同时根据图中节点的连通特性判断轮廓相交情况,并采用基于图和Delaunay三角剖分相结合的方法对相交轮廓进行修复。实验测试结果表明,该方法不仅能够有效处理切片轮廓相交等奇异情况,准确地获得各层切片有序轮廓,而且能够避免耗时的网格拓扑关系重建,运行效率较传统商业软件有显著提高。

In order to improve the efficiency and accuracy of slicing STL models for 3D printing,a slicing method to avoid contour intersection is proposed.Firstly,the triangle set on the model intersecting with the tangent plane is extracted,then the intersection points of the triangle set with the tangent plane are calculated and mapped as an undirected weighted graph.Finally,the intersection points of the graph are topologically sorted by depth-first searching algorithm.At the same time,the contour intersection conditions are judged according to the connectivity characteristics of the nodes in the graph,and the intersecting contours are repaired by combining graph and Delaunay triangulation method.Experimental results show that the proposed method can not only deal with the singular cases of contour intersection and accurately obtain the ordered slice contour of each layer,but also can avoid time-consuming reconstruction of mesh topological relations,so the operation efficiency is significantly improved compared with the traditional commercial software.