# Unable to build ROS python workspace on the RB5 drone Source: https://forum.modalai.com/topic/3717/unable-to-build-ros-python-workspace-on-the-rb5-drone Category: VOXL SDK and Software (https://forum.modalai.com/category/47/voxl-sdk-and-software) Tags: ros, rb5 Posted: 2024-08-13 17:46:53 UTC by Prabhav Gupta Replies: 2 · Views: 1603 ## Prabhav Gupta · 2024-08-13 17:46:53 UTC 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! ## Reply by Eric Katzfey (ModalAI staff) · 2024-08-14 15:10:56 UTC @Prabhav-Gupta said in [Unable to build ROS python workspace on the RB5 drone](/post/18593): > /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? ## Reply by Prabhav Gupta · 2024-08-14 16:37:48 UTC (in reply to Eric Katzfey) @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](/post/18593): > 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!