CAD-based path planning for 3-D line laser scanning

The problem of path planning for 3-D line laser scanning is addressed in th is article. The path under study is for a line, as opposed to a point in co nventional CNC and CMM toolpath planning. While the objective of the latter case is to drive a point along a curve, that of the former case is to driv e a line across a surface. To solve this problem, a path planning method is developed. First, a slicing approach is put forward to divide a part CAD m odel into a number of sections, since the laser scanning line is limited by the scanning width and a single scanning pass cannot cover the whole surfa ce. Second, for each section, at scanning pass is generated to cover the se ction surface. To ensure a maximum coverage for each section, the surface p rofile is determined, and the top of the scanning window is set along the u pper boundary of the surface profile. Third, combination of scanning all th e sections forms a complete scan of a surface. It is shown that with the pr oposed method a 3-D line laser scanning process can be effectively automate d. (C) 1999 Elsevier Science Ltd. All rights reserved.