Fast and Accurate Extrinsic Calibration for Multiple LiDARs and Cameras

In this letter, we propose a fast, accurate, and targetless extrinsic calibration method for multiple LiDARs and cameras based on adaptive voxelization. On the theory level, we incorporate the LiDAR extrinsic calibration with the bundle adjustment method. We derive the second-order derivatives of the cost function w.r.t. the extrinsic parameter to accelerate the optimization. On the implementation level, we apply the adaptive voxelization to dynamically segment the LiDAR point cloud into voxels with non-identical sizes, and reduce the computation time in the process of feature correspondence matching. The robustness and accuracy of our proposed method have been verified with experiments in outdoor test scenes under multiple LiDAR-camera configurations.