EXTRACTION OF ROAD-CROSSING POWER AND COMMUNICATION LINES FROM MOBILE MAPPING DATA

Abstract. In residential areas, maintenance of power and communication lines is an important issue. In recent years, the frequency and power of typhoons and storms have significantly increased. If utility poles incline due to strong winds, slack cables may contact with large vehicles. For automatically detecting loose road-crossing cables in wide areas, the MMS is very promising. However, when roadcrossing cables are measured using the MMS, large portions of points on cables may be lost, because the directions of laser beams are nearly parallel to the directions of road-crossing cables, and therefore, the laser beams cross road-crossing cables only a small number of times. In this paper, we propose a new method for reconstructing cables crossing roads. In our method, road-crossing cables are reconstructed using both point clouds and camera images. While point clouds of road-crossing cables may be partly missing, their camera images can be captured with little occlusion. Missing portions are recovered using lines extracted from camera images. First, points of each cable are extracted from a point cloud, and the 3D vertical plane on which the cable exists are calculated. From camera images, 2D line segments are extracted as candidates of cable lines. 2D line segments are projected onto the 3D vertical plane using the pinhole camera model. Finally, 3D cable lines are reconstructed on the 3D vertical plane from the merged points. In our experiments, road-crossing cables could be sufficiently extracted using our method.