Automatic Extrinsic Calibration Method for LiDAR and Camera Sensor Setups

TL;DR

This paper introduces a versatile, two-stage automatic calibration method for LiDAR and camera sensors that improves accuracy and ease of use in autonomous vehicle setups, validated through simulation and real-world tests.

Contribution

The paper presents a novel, generalizable calibration approach that handles different sensor modalities and resolutions, outperforming existing methods in accuracy and robustness.

Findings

Significantly outperforms existing calibration methods in synthetic tests.

Validates effectiveness through real-world experiments.

Provides open-source implementation for community use.

Abstract

Most sensor setups for onboard autonomous perception are composed of LiDARs and vision systems, as they provide complementary information that improves the reliability of the different algorithms necessary to obtain a robust scene understanding. However, the effective use of information from different sources requires an accurate calibration between the sensors involved, which usually implies a tedious and burdensome process. We present a method to calibrate the extrinsic parameters of any pair of sensors involving LiDARs, monocular or stereo cameras, of the same or different modalities. The procedure is composed of two stages: first, reference points belonging to a custom calibration target are extracted from the data provided by the sensors to be calibrated, and second, the optimal rigid transformation is found through the registration of both point sets. The proposed approach can handle devices with very different resolutions and poses, as usually found in vehicle setups. In order to assess the performance of the proposed method, a novel evaluation suite built on top of a popular simulation framework is introduced. Experiments on the synthetic environment show that our calibration algorithm significantly outperforms existing methods, whereas real data tests corroborate the results obtained in the evaluation suite. Open-source code is available at https://github.com/beltransen/velo2cam_calibration