Interactive scan planning for heritage recording

Terrestrial laser scanning has received attention as an efficient technology in the cultural heritage domain for recording the geometry of historic monuments quickly and precisely. It is important to find appropriate scanner configurations to make the scanning process efficient and to build reliable records. These configurations should satisfy required constraints such as full coverage, sufficient overlap, scan range limit, and laser incidence angle. This is called the view planning problem. We sought to develop a scan planning scheme for recording large monuments in the cultural heritage domain. Typical approaches to deal with the view planning problem, however, do not consider the specific requirements in this domain. In this paper, we propose an interactive scan planning approach that supports analytic computation as well as heuristic decision. It includes three supporting guides. A next scan grid supports semi-automated optimization in interactive planning, and scan geometry helps the user to intuitively decide the next best position in a feasible region. A knowledge guide, which is reasoned out by similar properties, provides the user with experts' heuristic solutions to aid practical planning. These guides support efficient scan planning in a complementary manner. We introduce the use of region of interest to obtain more accurate data for focused features. ScanPlanner is implemented on this basis. The result of tests showed that the proposed approach allows users to make efficient and reliable scan plans for heritage recording.