Point Cloud Computation for Object Slicing in 3-D Printing

Abstract

3-D printing has become a viable technology in the past several decades. The current state-of-the-art is to model the object using NURBS. Once the modeling has been completed, the object is converted into a tessellated model and saved as an STL file. The file is then passed onto a slicer that cuts the triangulated model into closed polygonal sections. The interior of the sections is filled with the required material and glued to the layer underneath. In principle this all sounds well, however, there are several fundamental problems with the tessellation as well as the slicing. This paper investigates the possibility to use a point cloud to address this issue. It uses the original NURBS model and converts the model into a point cloud, based on layer thickness and accuracy requirements, for direct slicing. The method requires no expensive tessellation, has no anomalies, needs no model repair and no conversion. The only major computational requirement is point evaluation which can be done error free and in an inexpensive manner. Such an approach may have been prohibitive a decade or so ago. However, with the proliferation of powerful hardware and the abundance of memory, point-based approaches are more than viable today.

Keywords: 3-D printing, NURBS, Point cloud, Object slicing

Downloads

Download the Paper Download the BiBTeX

Citation

William Oropallo, Les A. Piegl, Paul Rosen, and Khairan Rajab. Point cloud computation for object slicing in 3-d printing. In CAD Conference and Exhibition, pages 34--38, 2016. [ DOI ]

Bibtex


@inproceedings{Oropallo.2016.CADConf,
  title = {Point Cloud Computation for Object Slicing in 3-D Printing},
  author = {William Oropallo and Les A. Piegl and Paul Rosen and Khairan Rajab},
  booktitle = {CAD Conference and Exhibition},
  pages = {34--38},
  year = {2016},
  abstract = {3-D printing has become a viable technology in the past several decades. 
  	The current state-of-the-art is to model the object using NURBS. Once the modeling has 
	been completed, the object is converted into a tessellated model and saved as an STL 
	file. The file is then passed onto a slicer that cuts the triangulated model into closed 
	polygonal sections. The interior of the sections is filled with the required material 
	and glued to the layer underneath. In principle this all sounds well, however, there are 
	several fundamental problems with the tessellation as well as the slicing. This paper 
	investigates the possibility to use a point cloud to address this issue. It uses the 
	original NURBS model and converts the model into a point cloud, based on layer thickness 
	and accuracy requirements, for direct slicing. The method requires no expensive 
	tessellation, has no anomalies, needs no model repair and no conversion. The only major 
	computational requirement is point evaluation which can be done error free and in an 
	inexpensive manner. Such an approach may have been prohibitive a decade or so ago. 
	However, with the proliferation of powerful hardware and the abundance of memory, 
	point-based approaches are more than viable today.},
  keywords = {3-D printing, NURBS, Point cloud, Object slicing},
  doi = {10.14733/cadconfP.2016.34-38}
}