PX4 Development

Ubuntu Development Environment

On a clean Ubuntu environment (e.g., 18.04 LTS), we need to

• Run the script ubuntu.sh to install PX4 related dependencies (both hardware and simulation)

  • use arg --no-nuttx to omit NuttX/Pixhawk tools

  • use arg --no-sim-tools to omit jMAVSim and Gazebo9 simulator

• Install ROS Melodic by following the official ROS Wiki.

• Run the script ubuntu_sim_common_deps.sh to install common dependencies for simulation.

• Install MAVROS by following the instructions in its official repository.

  • we use source installation for development

  • use sudo for install_geographiclib_datasets.sh

  • echo "source ~/catkin_ws/devel/setup.bash --extend" >> ~/.bashrc

Notes

• ubuntu.sh is needed for both hardware and simulation

• ubuntu_sim_ros_melodic.sh is not used/recommended

  • To have more flexibility, we install three parts separately: ROS, sim dependencies, and MAVROS

Gazebo SITL Simulation

In order to run PX4 in Gazebo simulation, we have three more steps.

• build PX4 source code to generate a Iris quadrotor model in Gazebo (i.e. the target)

• set up environment variables

• roslaunch Gazebo simulation and run offboard control program

Build Iris quadrotor model in Gazebo

git clone [e-mail]:UCR-Robotics/PX4-Autopilot.git --recursive
cd PX4-Autopilot
DONT_RUN=1 make px4_sitl_default gazebo
# iris.sdf will be generated in PX4-Autopilot/Tools/sitl_gazebo/models/iris

Ser up environment variables

# may add the following to ~/.bashrc 
PX4_SRC_DIR=~/PX4-Autopilot
export GAZEBO_PLUGIN_PATH=$GAZEBO_PLUGIN_PATH:${PX4_SRC_DIR}/build/px4_sitl_default/build_gazebo
export GAZEBO_MODEL_PATH=$GAZEBO_MODEL_PATH:${PX4_SRC_DIR}/Tools/sitl_gazebo/models
export LD_LIBRARY_PATH=$LD_LIBRARY_PATH:${PX4_SRC_DIR}/build/px4_sitl_default/build_gazebo
export ROS_PACKAGE_PATH=$ROS_PACKAGE_PATH:${PX4_SRC_DIR}
export ROS_PACKAGE_PATH=$ROS_PACKAGE_PATH:${PX4_SRC_DIR}/Tools/sitl_gazebo

Run Offboard Control

• launch SITL and MAVROS by mavros_posix_sitl.launch

  • similar to px4.launch or posix_sitl.launch

• run offboard control C++ program by rosrun <package_name> offboard_node

References

• PX4 documentation: Ubuntu Development Environment

  • provides two bash scripts: ubuntu.sh and ubuntu_sim_ros_melodic.sh

  • build targets for Gazebo, jMAVSim, or NuttX

  • ROS/Gazebo and Raspberry Pi (armhf or aarch64)

• PX4 documentation: MAVROS installation
• PX4 documentation: ROS with Gazebo Simulation

  • set up environment variables

  • ROS launch files

• PX4 documentation: MAVROS Offboard Control C++ Example