Simulation

For developing missions for UASs using PX4 Autopilot, it is useful to set up the simulation environment provided by the software stack. For that, you need to download the resources introduced in the following sections.

TIP

We also recommend to check out the VS Code tasks related to launching a simulation which are available with the VS Code workspace template.

PX4 Autopilot

The simulation module for PX4 comes packaged with the source code. AutoAPMS requires at least v1.15.0.

git clone https://github.com/PX4/PX4-Autopilot.git --recursive

# Checkout specific version/branch and update submodules
PX4_VERSION=v1.15.0
(cd ./PX4-Autopilot && git checkout $PX4_VERSION && make submodulesclean)

# Install PX4 Autopilot dependencies on current system
sh ./PX4-Autopilot/Tools/setup/ubuntu.sh

If you ever find yourself switching revisions, you have to follow the steps below to cleanly update the PX4 source code:

cd ./PX4-Autopilot
make clean
make distclean
git checkout v1.15.0 # Switch version/tag/revision here
make submodulesclean # Make sure to update the submodules

Visit the Gaezebo Simulation Guide in the official documentation for learning how to launch a simulation environment for specific vehicles or introduce customized worlds.

Micro XRCE-DDS Agent

The Micro XRCE-DDS Agent is required to connect to the PX4 middleware and allow ROS 2 to interprete internal PX4 messages as ROS topics. The middleware is described in detail by the official documentation on the PX4-ROS 2/DDS Bridge. All you need to know for now is that you need to install the Micro XRCE-DDS Agent. We recommend adding the Git repository to your ROS workspace. Append the following snippet to your .repos file and fetch the package just like any other dependency using vcstool.

microxrcedds_agent:
    type: git
    url: https://github.com/eProsima/Micro-XRCE-DDS-Agent.git
    version: v2.4.2

NOTE

ROS 2 Humble doesn't support newer versions than 2.4.2 due to the fact that it only comes with Fast CDR 1.0.x.

As soon as the source code is available in your ROS workspace, you can build the package with colcon:

colcon build --packages-select microxrcedds_agent

Afterwards, you should be able to connect to the Micro XRCE-DDS client running on the simulator:

MicroXRCEAgent udp4 -p 8888

QGroundControl

QGroundControl (QGC) provides a powerful GUI that allows you to supervise and intervene with the current mission. It's really useful as a manual control panel when developing with AutoAPMS. Therefore, you should download the latest version of QGroundControl and follow the installation guide.

NOTE

As of now, the latest release of QGC does not yet show the names of custom ROS modes in the mode list.