Ros2: Set Gazebo clock publish rate

[HarunTeper]

Hello,

the default publish rate of the gazebo clock node is 10Hz. So far, it is most convenient to use the following approach to use Ros2 and Gazebo in a launch file for me:

gazebo_launch_cmd = IncludeLaunchDescription(
PythonLaunchDescriptionSource(os.path.join(pkg_gazebo_ros, 'launch', 'gazebo.launch.py')),
launch_arguments={'world': world}.items()
)
However, looking at the launch files and some other threads, I can't manage to set the publish_rate for the gazebo clock node. Is it possible to include the parameter .yaml file in the launch arguments or to include a parameter {'publish_rate': '10'} to the list of parameters, so that it can be set by the launch file.

[allenh1]

This is a duplicate of #1211 and #1247... Would be really great if this could be addressed. It makes the gazebo clock unusable for time-sensitive calculations.

[john-maidbot]

I had this same issue. Pretty frustrating 😅 If anyone else finds this, there is a workaround (it would be a good solution if not for the error message, but it worked for me on ros2 galactic, gazebo version 11.9.0):
https://answers.ros.org/question/378362/how-to-set-gazebo-clock-publish-rate-foxy/

[allenh1]

@john-maidbot I have a pull request (see #1332) for dealing with this... It works for all my purposes, but would require you to build from source.

[jacobperron]

#1391 has made it more convenient to set ROS parameters (including publish_rate) from the launch file.

[pinkponk]

For anyone else having problems with this and sees this issue, I finally got it to work with this:

    gazebo_params_path = os.path.join(
                    get_package_share_directory(package_name),'config','gazebo_params.yaml')
    gazebo_world_path = os.path.join(
                    get_package_share_directory(package_name),'worlds','AAAA.world')

    gazebo = IncludeLaunchDescription(
                PythonLaunchDescriptionSource([os.path.join(
                    get_package_share_directory('gazebo_ros'), 'launch', 'gazebo.launch.py')]),
                    launch_arguments={
                        'params_file': gazebo_params_path,
                                      'world': gazebo_world_path }.items()
         )

Dont forget to include the config dir in the CMakeList.txt

install(
  DIRECTORY config launch worlds
  DESTINATION share/${PROJECT_NAME}
)

gazebo_config.yaml

# gazebo_params.yml
gazebo:
    ros__parameters:
        publish_rate: 400.0