Zed-ros-wrapper: [BUG] ROS Noetic + Ubuntu 20.04: No Module named 'rospkg'

[Stigmaru]

Describe the bug
Running zed2.launch yields errors seemingly triggered by no module rospkg despite verifying that it is installed to /usr/lib/python3/...

Device information:

• OS: Ubuntu
• OS version: 20.04
• CPU: Intel Xeon E-2176 CPU @ 2.7GHz
• GPU Nvidia: Quadro P3200
• ZED SDK Version: ZED_SDK_Ubuntu18_cuda10.0_v3.1.2.run
• ROS Wrapper version: Latest https://github.com/stereolabs/zed-ros-wrapper#build-the-program

To Reproduce
Steps to reproduce the behavior:

1. Run roslaunch zed_wrapper zed2.launch
2. Get error

Expected behavior
Expected launch file to run

Screenshots
If applicable, add screenshots to help explain your problem.

Additional context
Running on new install of Ros Noetic with Ubuntu 20.04. Also had to use a different catkin_make command:
catkin_make -DPYTHON_EXECUTABLE=/usr/bin/python3 -DPYTHON_INCLUDE_DIR=/usr/include/python3.7m

[Myzhar]

Hi @AeroWRX
I'm sorry, but the ROS Wrapper has not yet been tested with Ubuntu 20.04 and ROS Noetic.
ROS Noetic uses Python3 instead of Python2 and not all the ROS packages work directly on ROS Noetic.

I found this solution for your problem:
https://answers.ros.org/question/245967/importerror-no-module-named-rospkg-python3-solved/

Let me know if it works for you

[adimehta03]

No @Myzhar , that did not work! Do you think its better to rollback to the previous Ubuntu version?

[Myzhar]

I think it's better. Furthermore there is no official support for CUDA in Ubuntu 20.04. We are waiting for it to release a version of the ZED SDK for Ubuntu 20.04.

[adimehta03]

@Myzhar I am a newbie to Ubuntu, is there any way to rollback to the previous version without losing any files?

[Myzhar]

I think that the only way is formatting. Unless you use a docker image based on Ubuntu 18.04

[2273024530]

sudo update-alternatives --config python
change your default version of python to python3

[adamanov]

The reason this error occurs is because Python packages in /opt are added to PYTHONPATH environment variable BUT for ones in /usr, path does not exist in PYTHONPATH variable. The python-rospkg gets installed in /usr by default. So you just need following line in .bashrc to fix this:

export PYTHONPATH=$PYTHONPATH:/usr/lib/python3.7/dist-packages

[brilliant-ember]

This worked for me, because by default python2 is the default so we have to explicitly tell the computer that we want python3 to be default so this fixed it for me.

 sudo apt install python-is-python3

https://answers.ros.org/question/39657/importerror-no-module-named-rospkg/?answer=363168#post-id-363168

[rohitdavas]

On ubuntu, the same issue I faced but after conda deactivate these issues are resolved.

I think if we have installed noetic or any distro as said in guide, the anaconda python is creating the problem.

try conda deactivate and it should be fine.
perhaps it would be nice if you turn off auto activation of base of conda using conda config --set auto_activate_base false

[awiseturtle]

This worked for me, because by default python2 is the default so we have to explicitly tell the computer that we want python3 to be default so this fixed it for me.

 sudo apt install python-is-python3

https://answers.ros.org/question/39657/importerror-no-module-named-rospkg/?answer=363168#post-id-363168

This worked for me too!

[LimingGao]

I fixed this issue by switching the default python version in my computer from python2.7 to pthon3.5
Switch command:
sudo update-alternatives --config python