Augmenting the iterative closest point (ICP) alignment algorithm with intensity
Geomatica , Volume 63 - Issue 4 p. 407- 418
TITAN® is a mobile terrestrial multi-LiDAR system. It uses GPS and an Inertial Measurement Unit (IMU) to determine its position and attitude. By using four LiDARs, the TITAN system has overlapping coverage. When the GPS signal is lost, the position error increases exponentially with the duration of the interruption. Drift in the position data manifests itself as a misalignment of the overlapping point clouds. By determining the change in pose required to align the overlapping point clouds, the amount of position drift can be estimated. This paper explores the feasibility of increasing position accuracy by incorporating corrections obtained from the alignment of overlapping LiDAR point clouds. The performance of point cloud alignment is improved by integrating intensity information into the Iterative Closest Point (ICP) alignment algorithm. Unfortunately, overlapping point clouds for the TITAN system contains little geometric and intensity variation. This severely limits the availability of areas on which to base an alignment.