YOCO: You Only Calibrate Once for Accurate Extrinsic Parameter in LiDAR-Camera Systems

TL;DR

This paper introduces a fully automatic, one-step extrinsic calibration method for LiDAR-camera systems that improves accuracy and automation by avoiding point registration, using plane point cloud analysis and optimization of extrinsic parameters.

Contribution

The proposed method eliminates the need for point registration in LiDAR-camera calibration, enabling automatic, precise, and robust extrinsic parameter estimation in a single step.

Findings

Outperforms existing calibration techniques in synthetic experiments.

Achieves less than 0.05 degree rotation and 0.015m translation errors in real-world tests.

Demonstrates robustness and automation in diverse LiDAR-camera setups.

Abstract

In a multi-sensor fusion system composed of cameras and LiDAR, precise extrinsic calibration contributes to the system's long-term stability and accurate perception of the environment. However, methods based on extracting and registering corresponding points still face challenges in terms of automation and precision. This paper proposes a novel fully automatic extrinsic calibration method for LiDAR-camera systems that circumvents the need for corresponding point registration. In our approach, a novel algorithm to extract required LiDAR correspondence point is proposed. This method can effectively filter out irrelevant points by computing the orientation of plane point clouds and extracting points by applying distance- and density-based thresholds. We avoid the need for corresponding point registration by introducing extrinsic parameters between the LiDAR and camera into the projection of extracted points and constructing co-planar constraints. These parameters are then optimized to solve for the extrinsic. We validated our method across multiple sets of LiDAR-camera systems. In synthetic experiments, our method demonstrates superior performance compared to current calibration techniques. Real-world data experiments further confirm the precision and robustness of the proposed algorithm, with average rotation and translation calibration errors between LiDAR and camera of less than 0.05 degree and 0.015m, respectively. This method enables automatic and accurate extrinsic calibration in a single one step, emphasizing the potential of calibration algorithms beyond using corresponding point registration to enhance the automation and precision of LiDAR-camera system calibration.