Extrinsic Calibration of 2D Laser Range Finders using Planar Features

摘要

2D Laser Range Finders, or 2D-LRFs, are essential sensors in the field of robotics, providing accurate range measurements with high angular resolution. These sensors can be assembled on top of systems which, by granting additional degrees of freedom to the movement of the LRF, enable the 3D reconstruction of a scene. The reconstruction procedure consists of the concatenation of each scan in a single point cloud representation. To do so, the extrinsic transformation between the LRF and the motorized system, in this case, a Pan-tilt unit, must be known with high accuracy, otherwise, the quality of the 3D reconstructed point clouds is insufficient. In this work, a calibration procedure which determines this transformation is proposed. The method does not require a dedicated marker, which is commonly necessary and has numerous disadvantages. Qualitative inspections show that the proposed method is able to significantly reduce artifacts which typically appear on uncalibrated point clouds. Furthermore, quantitative results demonstrate that the calibrated point cloud represents the geometries present in the scene with much higher accuracy when compared with the uncalibrated point cloud.