linefit_ground_segmentation
Implementation of the ground segmentation algorithm proposed in
@inproceedings{himmelsbach2010fast,
title={Fast segmentation of 3d point clouds for ground vehicles},
author={Himmelsbach, Michael and Hundelshausen, Felix V and Wuensche, H-J},
booktitle={Intelligent Vehicles Symposium (IV), 2010 IEEE},
pages={560--565},
year={2010},
organization={IEEE}
}
The linefit_ground_segmentation
package contains the ground segmentation library.
A ROS interface is available in linefit_ground_segmentation_ros
The library can be compiled separately from the ROS interface if you're not using ROS.
Installation
Requires the following dependencies to be installed:
- catkin_simple
https://github.com/catkin/catkin_simple.git
- eigen_conversions
sudo apt install ros-noetic-eigen-conversions
Compile using your favorite catkin build tool (e.g. catkin build linefit_ground_segmentation_ros
)
Launch instructions
The ground segmentation ROS node can be launch by executing roslaunch linefit_ground_segmentation_ros segmentation.launch
.
Input and output topic names can be specified in the same file.
Getting up and running with your own point cloud source should be as simple as:
- Change the
input_topic
parameter insegmentation.launch
to your topic. - Adjust the
sensor_height
parameter insegmentation_params.yaml
to the height where the sensor is mounted on your robot (e.g. KITTI Velodyne: 1.8m)
Parameter description
Parameters are set in linefit_ground_segmentation_ros/launch/segmentation_params.yaml
This algorithm works on the assumption that you known the height of the sensor above ground.
Therefore, you have to adjust the sensor_height
to your robot specifications, otherwise, it will not work.
The default parameters should work on the KITTI dataset.
Ground Condition
- sensor_height Sensor height above ground.
- max_dist_to_line maximum vertical distance of point to line to be considered ground.
- max_slope Maximum slope of a line.
- min_slope Minimum slope of a line.
- max_fit_error Maximum error a point is allowed to have in a line fit.
- max_start_height Maximum height difference between new point and estimated ground height to start a new line.
- long_threshold Distance after which the max_height condition is applied.
- max_height Maximum height difference between line points when they are farther apart than long_threshold.
- line_search_angle How far to search in angular direction to find a line. A higher angle helps fill "holes" in the ground segmentation.
- gravity_aligned_frame Name of a coordinate frame which has its z-axis aligned with gravity. If specified, the incoming point cloud will be rotated, but not translated into this coordinate frame. If left empty, the sensor frame will be used.
Segmentation
- r_min Distance at which segmentation starts.
- r_max Distance at which segmentation ends.
- n_bins Number of radial bins.
- n_segments Number of angular segments.
Other
- n_threads Number of threads to use.
- latch Latch output point clouds in ROS node.
- visualize Visualize the segmentation result. ONLY FOR DEBUGGING. Do not set true during online operation.