π€ AI Summary
To address the insufficient robustness of loop closure detection in LiDAR SLAM under cross-view and dynamic scenarios, this paper proposes a semantic graphβbased loop closure detection method leveraging Graph Attention Networks (GATs). We introduce object-level semantic graph modeling into LiDAR loop closure detection for the first time: PointPillars is employed to obtain semantic segmentation outputs, from which an explicit scene semantic graph is constructed to encode spatial structure and inter-object relationships. A GAT is then used to aggregate multi-hop semantic neighborhood information, learning interpretable node embeddings; loop closure is determined via graph-level similarity matching. Evaluated on the KITTI and Oxford RobotCar datasets, the method achieves a 12.3% improvement in mean Average Precision (mAP) and reduces false positive rate by 37%, significantly enhancing long-term localization robustness.