大尺寸STL模型单元化分割及切片处理算法研究

Cell division and slicing algorithm of large-scale STL model

3D打印技术可实现由数字化模型到实体模型的快速转换,但对于超大尺寸的模型,需要对其进行分割、堆叠、打包进而打印成型.本文针对大尺寸模型的分割打印问题,开展了相应的研究工作.首先,创建一个用于存放立体光刻(stereolithography,STL)模型的3D空间,分析并提取出模型的特征信息,根据3D打印机的加工范围进行单元划分.然后,对每个单元格内的三角面片进行直接切片处理,闭合轮廓直接生成打印区域,开放轮廓则先采用单元边界的修剪和映射处理,再将其闭合生成打印区域,进而获得单元模型的分层打印路径.最后,采用多喷头分区打印或单喷头多次打印,完成大尺寸模型的3D打印.通过典型模型的分割打印实验验证,本方法可以有效地对STL模型进行快速分割和切片处理,特别是对于超大尺寸的STL模型,简化了数据处理流程.

3D printing technology can realize the transformation from digital model to physical model.However,due to the limitation of the working volume of the printer,the maximum size of the single printing is still limited.For large size models,they need to be segmented,stacked,packaged and printed.In this paper,the segmentation and slicing algorithm of large-scale model is studied to optimize the large size model processing.First,a 3D space is created for storing the stereolithography(STL)model.The characteristic information of the model is analyzed and extracted.The model is divided into cells according to the processing scope of 3D printers.Then,the triangular facets in each cell are sliced directly.The closed contour is directly used to generate the printing layer.The open contour is closed by pruning and mapping of the cell boundary,and then the closed contour is used to generate the layer printing path.Finally,the printing layers of each cell model can be obtained.The 3D printing of large size model can be completed by using multi-nozzle partition printing or multiple printing with single nozzle.The experimental results of typical model segmentation and printing show that this algorithm can be used to effectively segment and slice the STL model,especially for the large-size STL model.This research work can simplify the data processing flow of large-scale 3D printing.