Scanned Data Triangulation Using Delaunay Tetrahedralization Approach for 3D Point Cloud Data

Abstract

Reverse Engineering (RE) is used to create surface models of existing products by capturing Point Cloud Data using either contact or non – contact scanners. Rapid Prototyping (RP) is used to fabricate the physical prototype of a product using a layer by layer additive technique. In this paper, a new method is suggested which creates a direct link between RE and RP. For RE process, 3D Laser Scanners have become more accurate and the speed of data acquisition has increased dramatically. However, handling of huge amount of Point Cloud Data is a major constraint. Rapid Prototyping (RP) demands solid model in Structured Tessellation Language (STL) format as a basic input. The three basic steps involved in creating a STL file from Point Cloud Data are as follows: 1) Data acquisition (Point Cloud Data), 2) Surface model and solid model development by using commercial software, 3) Generation of triangular mesh model using solid model and 4) STL file generation. This process is difficult; time consuming and laborious because gaps may appear in a surface model, being person dependent that may not allow the conversion of surface model into a perfect STL file. To overcome these steps, some researchers have suggested a technique in which STL file can be crated directly from the Point Cloud Data to avoid surface modeling tasks. Conventionally Delaunay triangulation is used for triangulation of 2D Point Cloud Data obtained from 3D Laser Scanner. In this paper, a new approach, “Delaunay Tetrahedralization” is suggested which is suitable for 3D Point Cloud Data. The efficiency of the algorithm is validated and the results are included in this paper.