Key Concepts
- LiDAR-Visual-Inertial (LVI) — Triple fusion for robust outdoor SLAM
- Tightly-coupled LiDAR-camera — Joint optimization of point cloud and visual features
- Direct LiDAR-camera alignment — Photometric/geometric alignment without feature extraction
- Degradation handling — Graceful fallback when one modality fails (e.g., LiDAR in rain, camera in darkness)
- Range image — 2D projection of LiDAR scans for efficient processing (SuMa, RangeNet++)
LiDAR / LiDAR-Inertial SLAM
| System | Author/Year | Key Concepts |
|---|---|---|
| LOAM | Zhang 2014 | LiDAR odometry and mapping (foundational), edge + planar features |
| SuMa | Behley (Bonn) 2018 | Surfel-based LiDAR SLAM, projective ICP on range images |
| SuMa++ | Chen (Bonn) 2019 | SuMa + RangeNet++ semantics, semantic ICP weighting, dynamic object filtering |
| LIO-SAM | Shan 2020 | Tightly-coupled LiDAR-inertial, factor graph, GPS fusion |
| FAST-LIO2 | Xu 2022 | Direct LiDAR-inertial, ikd-Tree, extremely fast |
| PIN-SLAM | Pan (Bonn) 2024 | Neural point cloud LiDAR SLAM, point-to-SDF registration, elastic map deformation for loop closure |
Visual-LiDAR Fusion SLAM
| System | Author/Year | Key Concepts |
|---|---|---|
| LVI-SAM | Shan 2021 | LiDAR-Visual-Inertial via factor graph, LIO-SAM + VINS-Mono |
| R3LIVE | Lin 2022 | Real-time LiDAR-Visual-Inertial, dense RGB point cloud map |
| R3LIVE++ | Lin 2023 | Improved R3LIVE with mesh reconstruction |
| FAST-LIVO | Zheng 2022 | FAST-LIO + direct visual odometry, tightly-coupled LVI |
| FAST-LIVO2 | Zheng 2024 | Improved, sequential image processing, direct photometric fusion |
| OKVIS2-X | Boche 2025 | Visual+Inertial+Depth+LiDAR+GNSS configurable (also in Level 6) |
Resources
| Resource | Author/Year | Key Concepts |
|---|---|---|
| Multi-Sensor Fusion SLAM Survey | Zhu 2024 | Camera + LiDAR + IMU fusion SLAM — comprehensive survey |