This ROS 2 module performs ground segmentation on LiDAR point clouds using the ground segmentation algorithm from the Robust Field Autonomy Lab, originally developed as part of the lego_loam SLAM system.
- The segmentation algorithm was proposed by Michael Himmelsbach and the publication is available at https://ieeexplore.ieee.org/document/5548059:
- The vertical structures identification was proposed by Igor Bogoslavskyi and the publication is available at https://ieeexplore.ieee.org/document/7759050:
Ground segmentation is a critical preprocessing step in many robotics applications such as autonomous navigation and SLAM. This implementation leverages the ground segmentation technique from LeGO-LOAM, which classifies ground and non-ground points in 3D LiDAR scans based on geometric features and elevation gradients.
- Efficient ground/non-ground point classification
- Compatible with standard point cloud formats (e.g., ROS
sensor_msgs/PointCloud2) - Designed for real-time performance in outdoor environments
- Can be integrated as a preprocessing node in SLAM or obstacle detection pipelines
/lidar/points(sensor_msgs/PointCloud2)
The input point cloud data, typically from a 3D LiDAR sensor. This topic should contain the full point cloud from which ground and segmented (non-ground) points will be extracted.
-
/ground_cloud(sensor_msgs/PointCloud2)
Contains only the points classified as ground. Useful for mapping flat surfaces or terrain. -
/segmented_cloud_pure(sensor_msgs/PointCloud2)
Contains the remaining non-ground points (e.g., obstacles, structures, vegetation).
| Parameter Name | Type | Default | Description |
|---|---|---|---|
num_vertical_scans |
int |
16 |
Number of vertical scan lines (rings) in the LiDAR sensor (e.g., Velodyne VLP-16). |
num_horizontal_scans |
int |
1800 |
Number of horizontal resolution bins. Higher values provide finer angular resolution. |
vertical_angle_bottom |
double |
-15.0 |
Vertical angle (in degrees) of the lowest LiDAR scan ring. |
vertical_angle_top |
double |
15.0 |
Vertical angle (in degrees) of the highest LiDAR scan ring. |
sensor_mount_angle |
double |
0.0 |
Mounting angle of the LiDAR sensor (in degrees). Adjust if the sensor is tilted. |
ground_scan_index |
int |
7 |
Index of the scan ring up to which points are considered for ground segmentation. |
| Parameter Name | Type | Default | Description |
|---|---|---|---|
segment_valid_point_num |
int |
5 |
Minimum number of consecutive valid points required in a segment to consider it valid. |
segment_valid_line_num |
int |
3 |
Minimum number of different scan lines that must contain valid points in a segment. |
segment_theta |
double |
60.0 |
Angle threshold (in degrees) used to determine whether a group of points belongs to the same segment. |
All parameters can be configured via a YAML configuration file or dynamically on the ROS parameter server.
- M. Himmelsbach, F.V. Hundelshausen, and H-J. Wuensche, “Fast Segmentation of 3D Point Clouds for Ground Vehicles,” Proceedings of the IEEE Intelligent Vehicles Symposium, pp. 560-565, 2010.
- I. Bogoslavskyi and C. Stachniss, “Fast Range Image-based Segmentation of Sparse 3D Laser Scans for Online Operation,” Proceedings of the IEEE/RSJ International Conference on Intelligent Robots and Systems, pp. 163-169, 2016.
- Shan, T. & Englot, B. (2018). LeGO-LOAM: Lightweight and Ground-Optimized Lidar Odometry and Mapping on Variable Terrain. IEEE IROS
This project is licensed under the GPLv3 license.