ArduPilot Gazebo Plugin

This is the official ArduPilot plugin for Gazebo. It replaces the previous ardupilot_gazebo plugin and provides support for the recent releases of the Gazebo simulator (Gazebo Garden) and (Gazebo Harmonic).

It also adds the following features:

• More flexible data exchange between SITL and Gazebo using JSON.
• Additional sensors supported.
• True simulation lockstepping. It is now possible to use GDB to stop the Gazebo time for debugging.
• Improved 3D rendering using the ogre2 rendering engine.

The project comprises a Gazebo plugin to connect to ArduPilot SITL (Software In The Loop) and some example models and worlds.

Prerequisites

Gazebo Garden or Harmonic is supported on Ubuntu 22.04 (Jammy). Harmonic is recommended. If you are running Ubuntu as a virtual machine you will need at least Ubuntu 20.04 in order to have the OpenGL support required for the ogre2 render engine. Gazebo and ArduPilot SITL will also run on macOS (Big Sur, Monterey and Venturua; Intel and M1 devices).

Follow the instructions for a binary install of Gazebo Garden or Gazebo Harmonic and verify that Gazebo is running correctly.

Set up an ArduPilot development environment. In the following it is assumed that you are able to run ArduPilot SITL using the MAVProxy GCS.

Installation

Install additional dependencies:

Ubuntu

Garden (apt)

Manual - Gazebo Garden Dependencies:

sudo apt update
sudo apt install libgz-sim7-dev rapidjson-dev
sudo apt install libopencv-dev libgstreamer1.0-dev libgstreamer-plugins-base1.0-dev gstreamer1.0-plugins-bad gstreamer1.0-libav gstreamer1.0-gl

Harmonic (apt)

Manual - Gazebo Harmonic Dependencies:

sudo apt update
sudo apt install libgz-sim8-dev rapidjson-dev
sudo apt install libopencv-dev libgstreamer1.0-dev libgstreamer-plugins-base1.0-dev gstreamer1.0-plugins-bad gstreamer1.0-libav gstreamer1.0-gl

Rosdep

Use rosdep with osrf's rosdep rules to manage all dependencies. This is driven off of the environment variable GZ_VERSION.

export GZ_VERSION=harmonic # or garden
sudo bash -c 'wget https://raw.githubusercontent.com/osrf/osrf-rosdep/master/gz/00-gazebo.list -O /etc/ros/rosdep/sources.list.d/00-gazebo.list'
rosdep update
rosdep resolve gz-harmonic # or gz-garden
# Navigate to your ROS workspace before the next command.
rosdep install --from-paths src --ignore-src -y

macOS

brew update
brew install rapidjson
brew install opencv gstreamer

Ensure the GZ_VERSION environment variable is set to either garden or harmonic.

Clone the repo and build:

git clone https://github.com/ArduPilot/ardupilot_gazebo
cd ardupilot_gazebo
mkdir build && cd build
cmake .. -DCMAKE_BUILD_TYPE=RelWithDebInfo
make -j4

Configure

Set the Gazebo environment variables in your .bashrc or .zshrc or in the terminal used to run Gazebo.

Terminal

Assuming that you have cloned the repository to $HOME/ardupilot_gazebo:

export GZ_SIM_SYSTEM_PLUGIN_PATH=$HOME/ardupilot_gazebo/build:$GZ_SIM_SYSTEM_PLUGIN_PATH
export GZ_SIM_RESOURCE_PATH=$HOME/ardupilot_gazebo/models:$HOME/ardupilot_gazebo/worlds:$GZ_SIM_RESOURCE_PATH

.bashrc or .zshrc

Assuming that you have cloned the repository to $HOME/ardupilot_gazebo:

echo 'export GZ_SIM_SYSTEM_PLUGIN_PATH=$HOME/ardupilot_gazebo/build:${GZ_SIM_SYSTEM_PLUGIN_PATH}' >> ~/.bashrc
echo 'export GZ_SIM_RESOURCE_PATH=$HOME/ardupilot_gazebo/models:$HOME/ardupilot_gazebo/worlds:${GZ_SIM_RESOURCE_PATH}' >> ~/.bashrc

Reload your terminal with source ~/.bashrc (or source ~/.zshrc on macOS).

Usage

1. Iris quad-copter

Run Gazebo

gz sim -v4 -r iris_runway.sdf

The -v4 parameter is not mandatory, it shows additional information and is useful for troubleshooting.

Run ArduPilot SITL

To run an ArduPilot simulation with Gazebo, the frame should have gazebo- in it and have JSON as model. Other commandline parameters are the same as usual on SITL.

sim_vehicle.py -v ArduCopter -f gazebo-iris --model JSON --map --console

Arm and takeoff

STABILIZE> mode guided
GUIDED> arm throttle
GUIDED> takeoff 5

2. Zephyr delta wing

The Zephyr delta wing is positioned on the runway for vertical take-off.

Run Gazebo

gz sim -v4 -r zephyr_runway.sdf

Run ArduPilot SITL

sim_vehicle.py -v ArduPlane -f gazebo-zephyr --model JSON --map --console

Arm, takeoff and circle

MANUAL> mode fbwa
FBWA> arm throttle
FBWA> rc 3 1800
FBWA> mode circle

Increase the simulation speed

The zephyr_runway.sdf world has a <physics> element configured to run faster than real time:

<physics name="1ms" type="ignore">
  <max_step_size>0.001</max_step_size>
  <real_time_factor>-1.0</real_time_factor>
</physics>

To see the effect of the speed-up set the param SIM_SPEEDUP to a value greater than one:

MANUAL> param set SIM_SPEEDUP 10

3. Streaming camera video

Images from camera sensors may be streamed with GStreamer using the GstCameraPlugin sensor plugin. The example gimbal models include the plugin element:

<plugin name="GstCameraPlugin"
    filename="GstCameraPlugin">
  <udp_host>127.0.0.1</udp_host>
  <udp_port>5600</udp_port>
  <use_basic_pipeline>true</use_basic_pipeline>
  <use_cuda>false</use_cuda>
</plugin>

The <image_topic> and <enable_topic> parameters are deduced from the topic name for the camera sensor, but may be overriden if required.

The gimbal.sdf world includes a 3 degrees of freedom gimbal with a zoomable camera. To start streaming:

gz topic -t /world/gimbal/model/mount/model/gimbal/link/pitch_link/sensor/camera/image/enable_streaming -m gz.msgs.Boolean -p "data: 1"

Display the streamed video:

gst-launch-1.0 -v udpsrc port=5600 caps='application/x-rtp, media=(string)video, clock-rate=(int)90000, encoding-name=(string)H264' ! rtph264depay ! avdec_h264 ! videoconvert ! autovideosink sync=false

Models

In addition to the Iris and Zephyr models included here, a selection of models configured use the ArduPilot Gazebo plugin is available in ArduPilot/SITL_Models. Click on the images to see further details.

Troubleshooting

For issues concerning installing and running Gazebo on your platform please consult the Gazebo documentation for troubleshooting frequent issues.