Unable to build ROS python workspace on the RB5 drone

[Prabhav Gupta]

Hi,

I am working on a RB5 Drone. I had setup a Python ROS workspace (ROS Melodic) and it was working okay up until a few days ago.

I had to upgrade the SDK on the drone to the latest available. After that, I have been facing issues with building the workspace.

This is the error I am facing while running catkin build:

rb5:~/python_ws$ catkin build obj_det                                                                                                                                                                                
/bin/sh: /home/root/python_ws/install/env.sh: Permission denied                                                                                                                                                      
WARNING: Sourced environment from `/home/root/python_ws/install/env.sh` has no environment variables. Something is wrong.                                                                                            
----------------------------------------------------------------------------------------------------------                                                                                                           
Profile:                     default                                                                                                                                                                                 
Extending:             [env] /home/root/catkin_ws/devel:/opt/ros/melodic                                                                                                                                             
Workspace:                   /home/root/python_ws                                                                                                                                                                    
----------------------------------------------------------------------------------------------------------                                                                                                           
Build Space:        [exists] /home/root/python_ws/build                                                                                                                                                              
Devel Space:        [exists] /home/root/python_ws/devel                                                                                                                                                              
Install Space:      [exists] /home/root/python_ws/install                                                                                                                                                            
Log Space:          [exists] /home/root/python_ws/logs                                                                                                                                                               
Source Space:       [exists] /home/root/python_ws/src                                                                                                                                                                
DESTDIR:            [unused] None
----------------------------------------------------------------------------------------------------------
Devel Space Layout:          linked
Install Space Layout:        merged
----------------------------------------------------------------------------------------------------------
Additional CMake Args:       -DPYTHON_EXECUTABLE=/usr/bin/python3 -DPYTHON_INCLUDE_DIR=/usr/include/python3.6m -DPYTHON_LIBRARY=/usr/lib/aarch64-linux-gnu/libpython3.6m.so
Additional Make Args:        None
Additional catkin Make Args: None
Internal Make Job Server:    True
Cache Job Environments:      False
----------------------------------------------------------------------------------------------------------
Whitelisted Packages:        None
Blacklisted Packages:        None
----------------------------------------------------------------------------------------------------------
Workspace configuration appears valid.
----------------------------------------------------------------------------------------------------------
[build] Found '5' packages in 0.0 seconds.
Starting  >>> cv_bridge               
/bin/sh: /home/root/python_ws/install/env.sh: Permission denied
WARNING: Sourced environment from `/home/root/python_ws/install/env.sh` has no environment variables. Something is wrong.
_________________________________________________________________________________________________________
Errors     << cv_bridge:check /home/root/python_ws/logs/cv_bridge/build.check.019.log
CMake Warning at /usr/share/cmake-3.10/Modules/FindBoost.cmake:1626 (message):
  No header defined for python3; skipping header check
Call Stack (most recent call first):
  CMakeLists.txt:11 (find_package)

CMake Error at /home/root/python_ws/src/vision_opencv/cv_bridge/CMakeLists.txt:16 (find_package):
  Could not find a package configuration file provided by "OpenCV" (requested
  version 3) with any of the following names:

    OpenCVConfig.cmake
    opencv-config.cmake

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


make: *** [cmake_check_build_system] Error 1
cd /home/root/python_ws/build/cv_bridge; catkin build --get-env cv_bridge | catkin env -si  /usr/bin/make cmake_check_build_system; cd -
.........................................................................................................
Failed     << cv_bridge:check          [ Exited with code 2 ]
Failed    <<< cv_bridge                [ 1.5 seconds ]
Abandoned <<< obj_det                  [ Unrelated job failed ]
[build] Summary: 0 of 2 packages succeeded.
[build]   Ignored:   3 packages were skipped or are blacklisted.
[build]   Warnings:  None.
[build]   Abandoned: 1 packages were abandoned.
[build]   Failed:    1 packages failed.
[build] Runtime: 1.6 seconds total.

I set this workspace up by following this tutorial on the web: https://medium.com/@beta_b0t/how-to-setup-ros-with-python-3-44a69ca36674

Any suggestions on what is going wrong here?

Thanks a lot!

[Eric Katzfey]

@Prabhav-Gupta said in Unable to build ROS python workspace on the RB5 drone:

/bin/sh: /home/root/python_ws/install/env.sh: Permission denied

This error looks suspicious. Does that file exist? Does it have execute permissions set on it?

[Prabhav Gupta]

@Eric-Katzfey

I had backed up my ROS workspace using adb pull before flashing the drone and used adb push to reinstate my workspace on the drone. This unfortunately changed up the file permissions for the folders within the workspace.

I was able to fix this by deleting (using rm -rf) all folders within my ROS workspace except the src (which contains the packages I was working on) and building the packages again.

I was then faced with the other CMake error visible above -

@Prabhav-Gupta said in Unable to build ROS python workspace on the RB5 drone:

CMake Error at /home/root/python_ws/src/vision_opencv/cv_bridge/CMakeLists.txt:16 (find_package):
Could not find a package configuration file provided by "OpenCV" (requested
version 3) with any of the following names:

OpenCVConfig.cmake
opencv-config.cmake

I fixed this by building opencv from source on the drone (following this - https://docs.opencv.org/4.x/d7/d9f/tutorial_linux_install.html)

After installing opencv, the catrkin build did not return any errors at the time. I do need to check whether my ROS Nodes are working as expected or not. Will update here once I do the same.

Thank you for your time!