A Weighted Ternary Feature Based Loop Closure Detection Method for LiDAR SLAM
摘要
In large-scale environments, LiDAR-based Simultaneous Localization and Mapping (SLAM) often encounters loop closure failures, resulting in uncorrected global accumulated errors. Compared with visual SLAM, which benefits from a variety of feature detectors and descriptors, LiDAR SLAM has received relatively limited attention in leveraging structural information for scene representation. To address this limitation, this study proposes a global descriptor based on weighted ternary features, which exhibits both rotation and translation invariance. Firstly, geometrically constrained planar and edge points are extracted to enhance the discriminative power of features. Then, a local adaptive coordinate system is constructed using each feature point and its principal orientation, enabling the extraction of stable and physically interpretable weighted ternary features and the parameterized modeling of point-to-point geometric relationships. Finally, a weighting mechanism that integrates normal vector deviation and curvature difference is introduced to strengthen local structural consistency, along with a density-based weighting strategy to capture global-level representations. Experimental results on the public KITTI dataset demonstrate that the proposed method reduces the root mean square error (RMSE) by up to 32% compared to LeGO-LOAM and improves the similarity score by up to 12% over Scan Context.