This paper addresses the problem of creating a consistent 3D scene in a common coordinate system from multiple views. The proposed algorithms allow to digitize large environments fast and reliably without any intervention and solve the 6D SLAM problem. A 360 3D laser scanner acquires data of the environment and interprets the 3D points online. A fast variant of the iterative closest points (ICP) algorithm  registers the 3D scans in a common coordinate system and relocalizes the robot. The registration uses a forest of approximate d-trees. The resulting approach is highly reliable and fast, such that it can be applied online to exploration and mapping in RoboCup Rescue.
The paper is organized as follows: The remainder of this section describes the state of the art in automatic 3D mapping and presents the autonomous mobile robot and the used 3D scanner. Section describes briefly the online extraction of semantic knowledge of the environment, followed by a discussion of the scan matching using forests of trees (section ). Section presents experiments and results and concludes.