LMBAO: A Landmark Map for Bundle Adjustment Odometry in LiDAR SLAM

TL;DR

This paper introduces LMBAO, a landmark map-based bundle adjustment odometry method for LiDAR SLAM that improves accuracy and real-time performance by active landmark maintenance and optimized sliding window management.

Contribution

The paper proposes a novel landmark map strategy for bundle adjustment odometry that enhances accuracy and efficiency in LiDAR SLAM, enabling real-time operation.

Findings

Achieves real-time performance in outdoor driving scenarios.

Outperforms state-of-the-art LiDAR SLAM algorithms like Lego-LOAM and VLOM.

Maintains high accuracy by active landmark management and optimized sliding window.

Abstract

LiDAR odometry is one of the essential parts of LiDAR simultaneous localization and mapping (SLAM). However, existing LiDAR odometry tends to match a new scan simply iteratively with previous fixed-pose scans, gradually accumulating errors. Furthermore, as an effective joint optimization mechanism, bundle adjustment (BA) cannot be directly introduced into real-time odometry due to the intensive computation of large-scale global landmarks. Therefore, this letter designs a new strategy named a landmark map for bundle adjustment odometry (LMBAO) in LiDAR SLAM to solve these problems. First, BA-based odometry is further developed with an active landmark maintenance strategy for a more accurate local registration and avoiding cumulative errors. Specifically, this paper keeps entire stable landmarks on the map instead of just their feature points in the sliding window and deletes the landmarks according to their active grade. Next, the sliding window length is reduced, and marginalization is performed to retain the scans outside the window but corresponding to active landmarks on the map, greatly simplifying the computation and improving the real-time properties. In addition, experiments on three challenging datasets show that our algorithm achieves real-time performance in outdoor driving and outperforms state-of-the-art LiDAR SLAM algorithms, including Lego-LOAM and VLOM.