Automated scan plan generation using STL meshes for 3D stripe-type laser scanner

Abstract

Reverse engineering and computer-aided inspection technologies play an important role in reducing the lead-time and improving the quality in the production of products containing complex and aesthetic surfaces. In this paper, we propose a laser scan planning system for complex freeform surfaces that is based on STL (STereoLithography) meshes. The developed laser scan planning system consists of three steps and it is assumed that the original CAD model of the part exists. Firstly, the surface model is approximated by STL meshes. The meshes are generated considering the curvature of the model so that more vertices are sampled in high curvature regions. From the mesh model, the region for which the scanning will be performed is selected and the normal vector of each node point is estimated. Secondly, scan directions and regions are determined through the region growing method. Also, scan paths are generated by generating a minimum-bound rectangle of points to be scanned. Finally, the generated scan directions and paths are validated by checking optical constraints and the collision avoidance. © Springer-Verlag 2003.