ROSConDemo/README.md

Apple Kraken Demo Project

This project demonstrates an example application of O3DE working with ROS 2. The integration is realized through ROS 2 Gem for O3DE.

How does it look like

The project includes

• Apple Orchard, a simulation scene with many rows of apple trees.
• Apple Kraken, a robot tasked with apple picking. It is ready to use and also included as an URDF.
  • Multiple Apple Krakens are supported
  • .. and you can spawn them using ROS 2 messages!
• Custom components for picking apples, which benefit from direct integration with ROS 2.
  • Yes, you can write ROS 2 code in O3DE!
• Autonomous operation which is based on ROS 2 navigation stack and ground truth.
  • Ground truth can be replaced with detectors based on sensor data. Give it a try!
• Apples
  • Thousands of apples!

Simulation scenes (levels)

Main Level

The main scene of the demo is set in an apple orchard surrounded by a countryside. The orchard is managed by the Apple Kraken.

The main level is rather performance intensive.

The Apple Kraken is a four-wheeled robot assigned the task of navigating around the orchard, collecting apples and storing them in its basket.

Playground Level

The playground scene is much lighter and can be used to quickly prototype with Kraken. There is only a couple of apple trees and the robot itself.

How to build the project and its dependencies

Requirements

Platforms

The project supports the following platforms:

• Ubuntu 22.04 with ROS 2 Humble
• Ubuntu 20.04 with ROS 2 Galactic

💡 Note: This demo is not supported on Windows!

O3DE

1. Refer to the O3DE System Requirements documentation to make sure that the system/hardware requirements are met.
2. Please follow the instructions to set up O3DE from GitHub.
3. Use the roscon_2022 branch: git checkout roscon_2022.

The following commands should prepare O3DE:

~$ git clone https://github.com/aws-lumberyard-dev/o3de.git
~$ cd o3de
~/o3de$ git lfs install
~/o3de$ git lfs pull
~/o3de$ git checkout roscon_2022
~/o3de$ python/get_python.sh
~/o3de$ scripts/o3de.sh register --this-engine

ROS 2 Gem

This project uses the ROS 2 Gem. Please make sure to follow the installation guide in README.md file. To learn more about how the Gem works check out the ROS 2 Gem user guide.

Note that the Gem instructions include installation of ROS 2 with some additional packages.

The Gem is open to your contributions!

Registering the Gem

During the step above, make sure to register the Gem in the engine: scripts/o3de.sh register --gem-path <PATH_TO_CLONED_ROS2_GEM>

Additional ROS 2 packages

The additional packages need to be installed. Use the following command:

sudo apt install ros-${ROS_DISTRO}-vision-msgs ros-${ROS_DISTRO}-nav-msgs ros-${ROS_DISTRO}-rmw-cyclonedds-cpp ros-${ROS_DISTRO}-cyclonedds

💡 Note: This is a dependency besides all the packages already required by the ROS 2 Gem.

Required environment settings

Some commands and environmental variables are necessary for ROS 2 systems, including this demo, to function properly. It is best to add these commands and settings to either ~/.bashrc or ~/.profile.

ROS 2 distribution and should always be sourced when building and running the demo and its command line interfaces. For a typical ROS 2 Humble installation, this would mean running the following for each console:

source /opt/ros/humble/setup.bash

Currently we are observing issues when running navigation with FastDDS (the default middleware for ROS 2 Humble). While the exact cause is yet to be investigated, there are no such issues when running with CycloneDDS. Thus, please set the following:

export RMW_IMPLEMENTATION=rmw_cyclonedds_cpp

Building this project

Build steps

1. Clone this project:

   git clone https://github.com/aws-lumberyard/ROSConDemo.git
   

2. Register this project in O3DE engine. In O3DE directory:

   scripts/o3de.sh register -pp <PATH_TO_THIS_PROJECT>
   

3. Ensure your ROS 2 is sourced:

   echo $ROS_DISTRO
   > humble
   

4. Configure build:

   cmake -B build/linux -G"Ninja Multi-Config" -DLY_DISABLE_TEST_MODULES=ON
   

5. Execute build (this will take a while the first time):

   cmake --build build/linux --config profile --target ROSConDemo Editor AssetProcessor ROSConDemo.Assets
   

Launching the Editor

Launch the O3DE Editor (in the Project directory):

build/linux/bin/profile/Editor

Running the demo scenario

You can try out the demo scenario as presented during ROSCon 2022. Take the following steps:

1. Launch the Editor and select the Main level. Allow it to load.
2. Run the simulation with Ctrl-G` or by pressing the Play button in the Editor. When it loads, you should be able to see the Apple Kraken.
3. Once the simulation is running, start the navigation stack. If you followed all the instructions, launch it with ros2 launch o3de_kraken_nav navigation.launch.py. You should see a new Rviz2 window.
4. Using RViz2, set the navigation goal using a widget in the toolbar (2D Goal Pose). You need to click and drag to indicate direction the robot will be facing. Make sure to set the goal next to an apple tree, to have the tree on the right side. Not too close, not too far. You can set subsequent goals for the robot to move around.
5. Once the robot arrives and stops next to the tree, you can trigger apple gathering.
6. Either wait for the robot to complete its job (gather all reachable apples) or cancel the gathering through the /cancel_apple_gathering service.
7. Select another navigation goal for the robot.
8. Spawn another Apple Kraken.

Controlling the Apple Kraken

Navigation

To run ROS 2 navigation stack with this Project, please use this repo for necessary instructions and packages.

Triggering Apple Gathering

Check available services in a terminal using this command:

• ros2 service list

If your simulation is running, you should be able to see the apple gathering service(s) listed there.

• It should be named /trigger_apple_gathering. It might include a namespace.

If Apple Kraken is in position, next to a tree, you can trigger apple gathering with this command:

• ros2 service call /trigger_apple_gathering std_srvs/srv/Trigger

You can also cancel a gathering operation in progress by calling another service:

• ros2 service call /cancel_apple_gathering std_srvs/srv/Trigger

Spawn more Krakens

Please read the following section on Robot Spawner.

To spawn a new Apple Kraken, you can used named points (provided by a Spawner Component) or custom poses. An example call:

ros2 service call /spawn_entity gazebo_msgs/srv/SpawnEntity '{name: 'apple_kraken', initial_pose: {position:{ x: 4, y: 4, z: 0.2}, orientation: {x: 0.0, y: 0.0, z: 0.0, w: 1.0}}}'

Troubleshooting

Check-list

• Is O3DE running ok with an empty or default project?
• Is ROS 2 installation ok? (check with ros2 topic pub etc.)
• Is ROS 2 workspace sourced? (check ROS_DISTRO, AMENT_PREFIX_PATH)
  • Note this needs to be true before cmake is ran. Re-run configuration and build when in doubt.
• Do you have compatible settings for crucial ENV variables when running the navigation / orchestration stack in the console and when running the simulator?
  • check RMW_IMPLEMENTATION, ROS_DOMAIN_ID etc.
• Check console for errors as well as logs. From the Project folder, check user/log/Editor.log.
• Are simulation topics up when you play the simulation?
  • ros2 node list should include /o3de_ros2_node
  • ros2 topic list should include /clock, /tf and /tf_static regardless of robot presence.
  • topic list should also include /pc, /ackermann_vel and /ground_truth_3D_detection if there is a robot in the scene and simulation is running.
    • note that with multiple robots, these topics will be namespaced.
  • ros2 service list should also show several simulation and robot services such as spawning and apple gathering.

Other

💡 Note: Take note that these vision_msgs are different between Humble and Galactic, in particular detection messages which are used by ground truth detector.

License

For terms please see the LICENSE*.TXT files at the root of this repository.