Basic information

Online documentation

https://rclUE.readthedocs.io/en/devel/

Supported versions

Main support

  • Ubuntu 20.04

  • Unreal Engine 5.10

  • ROS2 Foxy

  • Clang: 13.0.1

Maintenance/experimental

  • Ubuntu 22.04 and ROS2 Humble(UE5_devel_humble branch)

  • Ubuntu 24.04 and ROS2 Humble(UE5_devel_jazzy branch)

Please download UE5.10 for Linux by following Unreal Engine for Linux

Branches

  • devel: This build of the plugin is based on ROS2 Foxy and has been tested on Ubuntu 20 and UE5.10.

  • UE5_devel_foxy: Same as above.

  • UE5_devel_humble_20.04(experimental): This build of the plugin is based on ROS 2 humble and has been tested on Ubuntu 20.04 and UE5.1.

  • UE5_devel_humble(experimental): This build of the plugin is based on ROS 2 humble, Ubuntu 22.04 and UE5.1.

  • UE5_devel_jazzy(experimental): This build of the plugin is based on ROS 2 jazzy, Ubuntu 24.04 and UE5.1.

TroubleShooting

Missing library

Due to pre-compiled libraries, ThirdParty/ros/lib/librcl.so dynamically links libyaml.so and libspdlog.so.1, which needs to be provided by/installed on the host system. If not, Unreal fails to load the plugin or package the project without further details.

On some operating systems, even with libyaml and libspdlog installed, the version appendix may not exist. You can try creating them using:

cd /lib64
ln -s </path/to/libyaml.so.X.Y.Z> libyaml.so
ln -s </path/to/libspdlog.so.X.Y.Z> libspdlog.so.1

rclUE and ROS2

Description

  • We use ros2 ‘foxy’ lightweighted (not all binaries are included). Source/ThirdParty/ros folder is fully autogenerated by UE_tools

  • ros includes UE_msgs

  • UE uses centimeters but ROS uses meters. Please convert manually or use URRConversionUtils in RapyutaSimulationPlugins

  • within the Unreal Editor: Edit->Plugins, search and enable for rclc

Windows is currently unsupported

Getting Started

The plugin folder contains a video “Example_BP_PubSub.mp4” demonstrating how to setup a PubSub example in Blueprint.

An example setup using this plugin can be found at turtlebot3-UE

Notes on working with ROS 2 and UE

  • rcl and void* types cannot be managed by UE (no UPROPERTY) and therefore can’t be used directly in Blueprint. Whenever access to these variables is needed, the user should write a class to wrap it and all of their handling must be done in C++.

  • some basic numerical types are not natively supported in Blueprint (e.g. double, unsigned int). In order to use these, a workaround is needed (a plugin implementing those types for BP, a modified UE or a custom implementation).

  • In autogenerated messages, the method MsgToString() should be implemented by the user as its current purpose is to help debugging.

How to update ROS inside RclUE

Currently there is a scripts in UE_tools to automatically build and update ROS2 libraries. Please follow steps

Add CustomMsg in rclUE or other Plugins

Please check CustomMsgExample as a example of custom msg in different plugin then rclUE.

Install pre-commit

Please install pre-commit before commiting your changes. Follow this instruction https://pre-commit.com/

then run

pre-commit install

Documentation

Tools

documentation is built with three tools

Locally build

  1. install tools in #tools section.

  2. build

    cd docs
make --always-make html

  3. Open following in your browser.

    • Sphinx at file:///<path to cloned repo>/docs/source/_readthedocs/html/index.html

    • Original doxygen output at file:///<path to cloned repo>/docs/source/_readthedocs/html/doxygen_generated/html/index.html

Maintainer

yu.okamoto@rapyuta-robotics.com