PX4-ROS2-Gazebo Drone Simulation Template

This repository provides a template to set up a simulation environment for a quadcopter equipped with a camera. It integrates PX4, Gazebo Harmonic, and ROS2 Humble, enabling the development and testing of software for a drone with a companion computer. This environment is ideal for mission planning and computer vision applications. A Python example script is included to demonstrate how to control the drone and access the camera feed, serving as a starting point for further development.

Directory Structure

• PX4-Autopilot_PATCH/
  Contains custom worlds, models, and configurations to be copied into the PX4 installation. These files extend the default PX4 setup with additional simulation environments and drone models.

• ws_ros2/
  The ROS2 workspace where custom ROS2 nodes are developed and built. It includes the my_offboard_ctrl package, providing an example of drone control using ROS2.

Installation

This setup is tested on Ubuntu 22.04 and is not compatible with its derivatives (e.g., Linux Mint).

1. Clone the repository and run the installation script:

   cd ~
   git clone --recursive https://github.com/SathanBERNARD/PX4_Gazebo_ROS2_install_for_ubuntu.git
   cd ~/PX4_Gazebo_ROS2_install_for_ubuntu
   ./install_px4_gz_ros2_for_ubuntu.sh

2. Copy the custom worlds and models into the PX4 installation:

   cd ~/PX4_Gazebo_ROS2_install_for_ubuntu
   cp -r ./PX4-Autopilot_PATCH/* ~/PX4-Autopilot/

3. Install QGroundControl.

Usage (First Launch)

1. Launch QGroundControl

• Open QGroundControl.

2. Start the Micro XRCE-DDS Agent

• In a new terminal, start the Micro XRCE-DDS Agent:

  MicroXRCEAgent udp4 -p 8888

  The Micro XRCE-DDS Agent allows uORB messages to be published and subscribed to on a companion computer as ROS 2 topics.

  For more information, refer to the uXRCE-DDS documentation.

3. Run PX4 SITL and Gazebo

• In another terminal, launch PX4 SITL with Gazebo:

  PX4_SYS_AUTOSTART=4010 \
  PX4_SIM_MODEL=gz_x500_mono_cam \
  PX4_GZ_MODEL_POSE="1,1,0.1,0,0,0.9" \
  PX4_GZ_WORLD=test_world \
  ~/PX4-Autopilot/build/px4_sitl_default/bin/px4

  • PX4_SYS_AUTOSTART=4010 defines the airframe to be used by PX4. The 4010 airframe is the default for x500_mono_cam and is equivalent to the 4001 airframe.
  • PX4_SIM_MODEL=gz_x500_mono_cam specifies the model to load in Gazebo.
  • PX4_GZ_MODEL_POSE="1,1,0.1,0,0,0.9" sets the initial pose of the vehicle.
  • PX4_GZ_WORLD=test_world defines the Gazebo world to be loaded.

  Further information:

  • Gazebo Simulation Documentation
  • Airframes Reference
  • 4010 Airframe File

  In case of error message ERROR [gz_bridge] Service call timed out. try again.

4. Build and Run the ROS2 Node (Companion Computer Software)

• In a new terminal, build and run the ROS2 node:

  cd ~/PX4_Gazebo_ROS2_install_for_ubuntu/ws_ros2
  colcon build
  source install/local_setup.bash
  ros2 run my_offboard_ctrl offboard_ctrl_example

• To build only the my_offboard_ctrl package:

  colcon build --packages-select my_offboard_ctrl

  For additional details, refer to the ROS2 Package documentation.