python-octomap-2d

The python-octomap-2d project is a ROS2-based module for generating and managing octomaps, which are 2D occupancy grids used for robotic navigation.

The node subscribes to a point cloud, looks up the sensor origin via TF, integrates the scan into a 2D log-odds grid, and publishes two maps:

• Binary grid (-1 unknown / 0 free / 100 occupied)
• Probability grid (-1 unknown, else 0..100)

Implemented features

• Log-odds updates with global clamping & occupancy threshold
• Occlusion-aware free-space carving (first-hit stopping, optional occluder clearing)
• Angle binning (closest point per bearing) for efficient ray stops
• Dynamic canvas growth around the explored area
• Preprocessing: Z-band, range/FOV filters, density outlier removal

Topics

• Subscribes: sensor_msgs/PointCloud2 on io.input_topic (see config)
• Publishes:
  • Binary grid on io.output_topic (e.g., /projected_map)
  • Probability grid on io.output_prob_topic (e.g., /projected_map_prob)

Key Components

• config/configs.yaml: Configuration file for octomap parameters.
• src/: Contains Python scripts for octomap generation and processing:
  • msg_converter.py: Handles message conversions.
  • octomap_node.py: ROS 2 node (TF lookup, subscribers/publishers, timing)
  • octomap2d.py: core 2D mapper (log-odds + raycasting, dynamic growth)
  • preprocessor.py: Preprocesses data for octomap generation.
  • docker/ + docker-compose.yml — containerized runtime

Getting Started

Build the Docker Image

To build the Docker image for the octomap_ros2 service, run:

docker-compose build

Run the Octomap Node

To start the octomap_ros2 service, use:

docker-compose up

This will launch the octomap_node.py script inside the container.

Configuration

Modify the config/configs.yaml file to adjust octomap parameters as needed.