Unable to launch script

[fatburg3r]

Hi, I'm a beginner and just started learning px4 and mavros. I wanted to launch a python script obtained from the px4 User Guide website. https://docs.px4.io/main/en/ros/mavros_offboard_python.html

I created a ros package (package_px4), python script file (position.py), launch file (start.launch). As per the website, I added

source ~/Firmware/Tools/setup_gazebo.bash ~/Firmware ~/Firmware/build/px4_sitl_default
export ROS_PACKAGE_PATH=$ROS_PACKAGE_PATH:~/Firmware
export ROS_PACKAGE_PATH=$ROS_PACKAGE_PATH:~/Firmware/Tools/sitl_gazebo
export GAZEBO_PLUGIN_PATH=$GAZEBO_PLUGIN_PATH:/usr/lib/x86_64-linux-gnu/gazebo-9/plugins

at the end of the .bashrc file.

I tried to source the .bashrc file but the terminal gave me this output.

GAZEBO_PLUGIN_PATH :/usr/lib/x86_64-linux-gnu/gazebo-9/plugins:/usr/lib/x86_64-linux-gnu/gazebo-9/plugins:/usr/lib/x86_64-linux-gnu/gazebo-9/plugins:/usr/lib/x86_64-linux-gnu/gazebo-9/plugins:/home/syuant/Firmware/build/px4_sitl_default/build_gazebo:/usr/lib/x86_64-linux-gnu/gazebo-9/plugins:/home/syuant/Firmware/build/px4_sitl_default/build_gazebo:/usr/lib/x86_64-linux-gnu/gazebo-9/plugins:/home/syuant/Firmware/build/px4_sitl_default/build_gazebo:/home/syuant/Firmware/build/px4_sitl_default/build_gazebo:/home/syuant/Firmware/build/px4_sitl_default/build_gazebo:/home/syuant/Firmware/build/px4_sitl_default/build_gazebo:/home/syuant/Firmware/build/px4_sitl_default/build_gazebo
GAZEBO_MODEL_PATH :/home/syuant/Firmware/Tools/sitl_gazebo/models:/home/syuant/Firmware/Tools/sitl_gazebo/models:/home/syuant/Firmware/Tools/sitl_gazebo/models:/home/syuant/Firmware/Tools/sitl_gazebo/models:/home/syuant/Firmware/Tools/sitl_gazebo/models
LD_LIBRARY_PATH /home/syuant/ros_workspace/devel/lib:/opt/ros/noetic/lib:/home/syuant/Firmware/build/px4_sitl_default/build_gazebo:/home/syuant/Firmware/build/px4_sitl_default/build_gazebo:/home/syuant/Firmware/build/px4_sitl_default/build_gazebo:/home/syuant/Firmware/build/px4_sitl_default/build_gazebo:/home/syuant/Firmware/build/px4_sitl_default/build_gazebo

When I tried launching the script roslaunch package_px4 start.launch, I still got this error

Resource not found: px4
ROS path [0]=/opt/ros/noetic/share/ros
ROS path [1]=/home/syuant/ros_workspace/src/mavlink
ROS path [2]=/home/syuant/ros_workspace/src/mavros/libmavconn
ROS path [3]=/home/syuant/ros_workspace/src/mavros/mavros_msgs
ROS path [4]=/home/syuant/ros_workspace/src/mavros/mavros
ROS path [5]=/home/syuant/ros_workspace/src/mavros/mavros_extras
ROS path [6]=/home/syuant/ros_workspace/src/package_alpha
ROS path [7]=/home/syuant/ros_workspace/src/package_px4
ROS path [8]=/home/syuant/ros_workspace/src/mavros/test_mavros
ROS path [9]=/opt/ros/noetic/share
The traceback for the exception was written to the log file

Any ideas on why this is happening? Thanks in advance.

[stevenchangg]

Hello @fatburg3r Did u manage to find a solution to this issue? Because I am facing the exact same problem rn 😅 Thanks in advance!

[fatburg3r]

I didn't figure out what was wrong, I got it working on the second try but not on the third. Not sure if this will help, but here's the end of my .bashrc file.

# for ros1 noetic
source /opt/ros/noetic/setup.bash
source ~/ros_workspace/devel/setup.bash

source ~/Firmware/Tools/setup_gazebo.bash ~/Firmware ~/Firmware/build/px4_sitl_default
export ROS_PACKAGE_PATH=$ROS_PACKAGE_PATH:~/Firmware
export ROS_PACKAGE_PATH=$ROS_PACKAGE_PATH:~/Firmware/Tools/sitl_gazebo
export GAZEBO_PLUGIN_PATH=$GAZEBO_PLUGIN_PATH:/usr/lib/x86_64-linux-gnu/gazebo-9/plugins
export GAZEBO_MODEL_PATH=$GAZEBO_MODEL_PATH:/home/syuant/Firmware/Tools/sitl_gazebo/models

[AlexWUrobot]

I solved it by this way, based on Ubuntu 18.04 and Python 3.6 https://discuss.px4.io/t/mavros-posix-sitl-launch-is-neither-a-launch-file-in-package-px4-nor-is-px4-a-launch-file-name/30522 https://docs.px4.io/main/en/simulation/ros_interface.html

[topiga]

Hey @fatburg3r, did you find a solution for this : https://discuss.px4.io/t/failed-to-use-mavlink-mav-cmd-set-message-interval/28921 I’m having exactly the same problem as you do