DLBAcalib: Robust Extrinsic Calibration for Non-Overlapping LiDARs Based on Dual LBA

TL;DR

This paper introduces DLBAcalib, a targetless, robust extrinsic calibration method for non-overlapping LiDARs that leverages bundle adjustment and iterative refinement to improve accuracy without manual intervention.

Contribution

It presents a novel joint optimization framework combining LiDAR bundle adjustment with adaptive outlier resistance for non-overlapping LiDAR calibration.

Findings

Achieves 5 mm translational and 0.2° rotational accuracy

Operates without infrastructure or manual tuning

Outperforms existing calibration methods in robustness

Abstract

Accurate extrinsic calibration of multiple LiDARs is crucial for improving the foundational performance of three-dimensional (3D) map reconstruction systems. This paper presents a novel targetless extrinsic calibration framework for multi-LiDAR systems that does not rely on overlapping fields of view or precise initial parameter estimates. Unlike conventional calibration methods that require manual annotations or specific reference patterns, our approach introduces a unified optimization framework by integrating LiDAR bundle adjustment (LBA) optimization with robust iterative refinement. The proposed method constructs an accurate reference point cloud map via continuous scanning from the target LiDAR and sliding-window LiDAR bundle adjustment, while formulating extrinsic calibration as a joint LBA optimization problem. This method effectively mitigates cumulative mapping errors and achieves outlier-resistant parameter estimation through an adaptive weighting mechanism. Extensive evaluations in both the CARLA simulation environment and real-world scenarios demonstrate that our method outperforms state-of-the-art calibration techniques in both accuracy and robustness. Experimental results show that for non-overlapping sensor configurations, our framework achieves an average translational error of 5 mm and a rotational error of 0.2{\deg}, with an initial error tolerance of up to 0.4 m/30{\deg}. Moreover, the calibration process operates without specialized infrastructure or manual parameter tuning. The code is open source and available on GitHub (\underline{https://github.com/Silentbarber/DLBAcalib})