Python version conflict between rclpy and ros-humble-realsense2-camera

[chenzhejin]

Hello experts,

I followed the installation tutorial and successfully installed all the required packages. However, when I tried to run the following command:

ros2 launch propif_bringup system.launch.py

I encountered the following error:

(propif_ros2) chenzhe@...:~/ProPIF_workspace/ProPIF/propif_ros2$ source install/setup.bash
(propif_ros2) chenzhe@...:~/ProPIF_workspace/ProPIF/propif_ros2$ ros2 launch propif_bringup system.launch.py

Output:

Both the simulation_node and control_node processes failed with a ModuleNotFoundError:

ModuleNotFoundError: No module named 'rclpy._rclpy_pybind11'
The C extension '/home/chenzhe/miniforge3/envs/propif_ros2/lib/python3.11/site-packages/_rclpy_pybind11.cpython-310-x86_64-linux-gnu.so' isn't present on the system.

This error seems to be caused by Python version mismatch and the rclpy C extension not being properly built. According to the ROS 2 Humble documentation, ROS 2 Humble officially supports Python 3.10.

So, I attempted to fix this by modifying environment.yml, changing the Python version from 3.11 to 3.10. However, I then encountered another issue when trying to create the environment:

mamba env create -f environment.yml

Error:

libmamba Could not solve for environment specs

The following packages are incompatible:

├─ python =3.10 * 
│  ├─ installable: python 3.10.8
│  └─ requires: python_abi =3.10 *_cp310
└─ ros-humble-realsense2-camera 
   └─ requires: python_abi =3.11 *_cp311, which conflicts with the above

This means the ros-humble-realsense2-camera package only supports Python 3.11, but switching to Python 3.11 breaks compatibility with the core rclpy module.

Since ros-humble-realsense2-camera is essential, simply removing it doesn't seem to be a reasonable solution.

I would appreciate any guidance or suggestions on how to properly resolve this version conflict.
Is there a recommended way to either:

Use Python 3.10 and still include ros-humble-realsense2-camera, or

Use Python 3.11 and successfully rebuild all necessary rclpy C extensions?

Thank you in advance!

[typedefSY]

Hi Chenzhe,

On my own machine, I used Python 3.11 for this project. I think the problem here is your ROS2 packages were compiled for Python 3.10, but your environment is using Python 3.11.
Since the official ROS2 Humble packages (from apt) only support Python 3.10, I recommend using RoboStack packages like I do, which support multiple Python versions.
Could you try to create a new clean env and use RoboStack packages instead of official ROS2-Humble? Please LMK if you meet any issues :)

[chenzhejin]

Ok i'll try this later, thank you for your support