Getting A Head Start With iRobot Create3 (ROS2)

Question

With the announcement of the iRobot Create3 "with ROS2 support", and to get a head start playing with it, iRobot has some create3 GitHub repos:

• https://github.com/iRobotEducation/create3_sim
• https://github.com/iRobotEducation/create3_examples and apparently a dependency on:
• https://github.com/iRobotEducation/irobot_create_msgs

I have started a "Create3 ROS2 Controller" with a RaspberryPi3B running ROS2 Galactic over 64-bit Ubuntu 20.04 Server.

Since this is a headless, no desktop install, I have not installed the create3_sim repo.

Where should I put irobot_create_msgs and how do I build it?

My tree:

$ tree -L 2
├── create3ros
│   ├── create3_examples_ws
│   ├── create3_ws

This is the error:

ubuntu@CREATE3:~/create3ros/create3_examples_ws$ colcon build
Starting >>> create3_examples_msgs
Starting >>> create3_examples_py
Finished <<< create3_examples_py [5.42s]                                                           
[Processing: create3_examples_msgs]                             
Finished <<< create3_examples_msgs [49.4s]                       
Starting >>> create3_coverage
--- stderr: create3_coverage                          
CMake Error at CMakeLists.txt:22 (find_package):
  By not providing "Findirobot_create_msgs.cmake" in CMAKE_MODULE_PATH this
  project has asked CMake to find a package configuration file provided by
  "irobot_create_msgs", but CMake did not find one.

  Could not find a package configuration file provided by
  "irobot_create_msgs" with any of the following names:

    irobot_create_msgsConfig.cmake
    irobot_create_msgs-config.cmake

  Add the installation prefix of "irobot_create_msgs" to CMAKE_PREFIX_PATH or
  set "irobot_create_msgs_DIR" to a directory containing one of the above
  files.  If "irobot_create_msgs" provides a separate development package or
  SDK, be sure it has been installed.


---
Failed   <<< create3_coverage [7.51s, exited with code 1]

Summary: 2 packages finished [58.1s]
  1 package failed: create3_coverage
  1 package had stderr output: create3_coverage
```

Answer 1

For anyone looking for the answer for ROS2 Humble, there is an easy package

sudo apt install -y ros-humble-irobot-create-msgs

Answer 2

Got it: Needed to clone the msgs into the same src dir as the examples:

$ tree -L 4
.
├── create3ros
│   ├── create3_examples_ws
│   │   └── src
│   │       ├── create3_examples
│   │       └── irobot_create_msgs

and the build proceeds and succeeds after 16min 31s.