Vehicle does not repond to ROS thruster commands until a gazebo topic echo command is issued.

[rolker]

Describe the bug

After initial startup using competition.launch.py launch file, the simulated USV does not respond to ROS thruster messages. One way to get the USV to respond to the ROS messages is to issue a gz topic --echo --topic command with the relevant topic.

It seems like the ROS to gazebo bridge needs a bit of prodding to work correctly.

Expected behavior
I expect to see the USV move when a "ros2 topic pub" command is used to set the thruster values, but it stays still most of the time.

To Reproduce
List the steps to reproduce the problem:

1. In a terminal, run: ros2 launch vrx_gz competition.launch.py
2. In a separate terminal, run: ros2 topic pub /wamv/thrusters/right/thrust std_msgs/msg/Float64 "data: 100"
3. Observe a message in the first terminal acknowledging that the parameter bridge is passing the message from ROS to Gazebo, yet the USV is not reacting.
4. In yet another terminal, with the ros2 topic pub still sending at 1hz, run: gz topic --echo --topic /wamv/thrusters/right/thrust
5. Observe the USV finally start to spin in a slow circle

System Configuration:

• OS: Ubuntu 24.04
• ROS Version: ROS 2 Jazzy
• Gazebo Version:

gz sim --version
Gazebo Sim, version 8.9.0

• Graphics Card: Nvidia RTX 2080
• Are you using VRX or VRX Classic? (The default is VRX). The default jazzy branch from this repo.

Screenshots
N/A

Additional notes

The following shows up in the simulator terminal as soon as the first ROS message is sent.

[parameter_bridge-8] [INFO] [1763046730.454144965] [wamv.ros_gz_bridge]: Passing message from ROS std_msgs/msg/Float64 to Gazebo gz.msgs.Double (showing msg only once per type)

Data streams from the sensors are available as soon as the simulation starts and can be observed in rviz.

Once the thrusters decide to respond, the rest of the simulation seems to be working fine.

[stepanove]

Funny enough, I use basically the same commands to reproduce my issue (#866) and I haven't noticed any problems with the thrusters' responsiveness. I use the latest Docker-based development environment (version 3.0.4) and have tried to reproduce this issue several times with both the stock image (Gazebo 8.9) and the image updated to current versions of Ubuntu packages (Gazebo 8.10), without success.

[rolker]

Funny enough, I use basically the same commands to reproduce my issue (#866) and I haven't noticed any problems with the thrusters' responsiveness. I use the latest Docker-based development environment (version 3.0.4) and have tried to reproduce this issue several times with both the stock image (Gazebo 8.9) and the image updated to current versions of Ubuntu packages (Gazebo 8.10), without success.

In my case, I'm building the environment locally and not using Docker. I have noticed the oscillations you mention is your issue...

[stepanove]

In my case, I'm building the environment locally and not using Docker.

This suggests you might have some issues in your setup, what ros_gz_brige version do you have?
ros2 pkg xml ros_gz_bridge -t version

The docker dev environment comes with ros_gz_brige v1.0.16.

[stepanove]

@rolker, you might use my VRX playground project to compare packages versions and system configs. I'd suggest you give docker and VSCode devcontainers a chance. It's very convenient to have a complete development environment with customized IDE right in your repo. It makes collaboration much easier, everyone gets a clean, reproducible environment right out of the box and it comes virtually for free, all it takes is just a couple of text files.

btw, I've started looking at VRX with the idea of getting in touch with Nav2 and maybe trying to write plugins for it someday. It turns out you are there already:) I've added your Nav2 plugins to my playground and switched to your crabbing path follower:)

[rolker]

ros2 pkg xml ros_gz_bridge -t version

1.0.16

It's what got installed from following the documented install procedure.

[rolker]

@rolker, you might use my VRX playground project to compare packages versions and system configs. I'd suggest you give docker and VSCode devcontainers a chance. It's very convenient to have a complete development environment with customized IDE right in your repo. It makes collaboration much easier, everyone gets a clean, reproducible environment right out of the box and it comes virtually for free, all it takes is just a couple of text files.

btw, I've started looking at VRX with the idea of getting in touch with Nav2 and maybe trying to write plugins for it someday. It turns out you are there already:) I've added your Nav2 plugins to my playground and switched to your crabbing path follower:)

Cool! Your screenshot from your playground looks a lot like what I'm getting in RViz which is reassuring! :)

I did give dev containers a try while porting from noetic, but the container would crash often enough without giving me any hints to why that I decided it wasn't worth the extra friction for me at the time. I'll probably give another try someday.

Glad you found the crabbing path follower and that it's working for you! I wrote it a few years ago as a placeholder to allow our boats to drive a straight line in the strong currents in our local harbour, thinking it would get replaced with something more sophisticated eventually, but I haven't done so yet.

[stepanove]

ros2 pkg xml ros_gz_bridge -t version

1.0.16

It's what got installed from following the documented install procedure.

Maybe check other Gazebo relates packages.

Here is a list of packages in the stock 3.0.4 image:
packages-v3.0.4.txt
And here is what you get if you update everything to the current state of Ubuntu 24.04 (like in my devcontainer):
packages-v3.0.4-updated.txt

You cant try to just update your system, but it might be not so easy to revert, that's one of the reasons to use containers :)

btw, there is a small issue with Gazebo 8.10 and VRX. Gazebo spams with warnings about dummy_upper link, it looks like this warning is explicitly suppressed in VRX, but new Gazebo doesn't respect it for some reason. I mitigate it by adjusting Gazebo verbosity level in my playground launch file.

[stepanove]

Glad you found the crabbing path follower and that it's working for you! I wrote it a few years ago as a placeholder to allow our boats to drive a straight line in the strong currents in our local harbour, thinking it would get replaced with something more sophisticated eventually, but I haven't done so yet.

I'm new to marine robotics and there is not so much info on USV control on the web, compared to other types of vehicles. So your work will certainly serve me as a useful example when/if I get to implementing something :)

[ecschuetz]

hey @rolker , i have the exact same issue. thanks for sharing your workaround with "gz topic --echo --topic"

i need to echo all relevant topics so the wamv can drive. without "gz topic --echo --topic" it wont work.

i am on ubuntu 24.04 with ROS2 jazzy

gz sim --version

Gazebo Sim, version 8.9.0
Copyright (C) 2018 Open Source Robotics Foundation.
Released under the Apache 2.0 License.

ros2 pkg xml ros_gz_bridge -t version
1.0.16

have someone found a solution?

problem seems to be ros_gz_bridge?
sometimes launching it, it will work, sometimes not. very unreliable...

[stepanove]

Hi @ecschuetz, I have no such issues with vrx-devel docker image, but I see it builds some Gazebo related packages instead of using apt version, maybe it's related.
https://github.com/osrf/vrx/blob/260fa40976e87cb33f417d61762b9a0cec17cafb/docker/Dockerfile.base#L42C24-L42C62

[stepanove]

Hi @rolker , @ecschuetz , have you managed to fix the issue?
I tried to reproduce it with a stock osrf/ros:jazzy-desktop-full image, but it worked fine. I started a container and manually followed instructions from wiki. The only problem was to install sdformat14, it required adding OSRF repo.