The cob_3d_mapping_features package provides feature extraction and segmantation algorithms in order to describe point clouds.

ROS API

plane_extraction_nodelet

The plane_extraction_nodelet nodelet takes in sensor_msgs/PointCloud2 messages and extracts planes using RANSAC. Convex hull polygons are calculated for each plane and publish as a cob_3d_mapping_msgs/ShapeArray

Subscribed Topics

/point_cloud2 (sensor_msgs/PointCloud2)

• The input point cloud

Published Topics

/shape_array (cob_3d_mapping_msgs/ShapeArray)

• The extracted hull polygons

/visualization_marker (visualization_msgs/Marker)

• The extracted hull polygons as Marker for RViz

Parameters

~plane_constraint (int, default: 0)

• Constrain the planes extracted (0=NONE, 1=HORIZONTAL, 2=VERTICAL)

~voxel_leafsize (double, default: 0.04)

• Voxel resolution for down-sampling (in m)

~passthrough_min_z (double, default: -0.1)

• Minimum z value for pass-through filter (in m)

~passthrough_max_z (double, default: 3)

• Maximum z value for pass-through filter (in m)

~cluster_tolerance (double, default: 0.05)

• Minimum distance between points for clustering (in m)

~alpha (double, default: 0.1)

• Alpha value for convex hull

~target_frame (string, default: map)

• The frame input data is transformed to

~mode_action (bool, default: false)

• Use action or topic mode

~save_to_file (bool, default: false)

• Flag for saving the map as a PCD file after each update (for debugging)

~file_path (string, default: /tmp)

• File path for saving the map

Usage/Examples

Plane Extraction

Launch the plane extraction

roslaunch cob_3d_mapping_features extract_planes.launch