Velocity command interface is broken on rolling+ionic

[christophfroehlich]

Describe the bug
Velocity command interface is broken on rolling+ionic? position interfaces work

To Reproduce
Steps to reproduce the behavior:

1. ros2 launch gz_ros2_control_demos diff_drive_example.launch.py
2. ros2 run gz_ros2_control_demos example_diff_drive
3. nothing moves

same with cart_velocity example

Environment (please complete the following information):

• OS: Ubuntu noble
• Version rolling from source, ros-rolling-gz-sim-vendor 0.2.0, ionic 9.0.0

Additional context
The same examples work on humble+fortress.

[saikishor]

I've tested this on Jazzy and it is working. I will also test it on rolling and update here

[christophfroehlich]

I can confirm, it works with jazzy and harmonic 8.7.
Harmonic + rolling version of gz_ros2_control also works.

I just have rebuilt my rolling docker and workspace, but still the robots don't move on ionic.

[saikishor]

I confirm that in rolling it doesn't work 🙏🏽

[christophfroehlich]

@azeey Could you please help us here? What has changed from Harmonic to Ionic, so that velocity commands are not working any more?

[JuuHuu]

After the update, my differential car cannot move in Gazebo Harmonic + Jazzy. However it can be controlled before the update. Finally i find it is because i set linear.x.max_jerk: and other jerk limits in controller config file to 0. It should be set to .NAN.

[christophfroehlich]

If you have had has_jerk_limits=false in your parameter file, it should have printed you a warning? Otherwise it should not have worked before already 🤔
However, this is not related to this issue here.