# Error when launching mpa_to_ros2

Source: https://forum.modalai.com/topic/3582/error-when-launching-mpa_to_ros2
Category: VOXL SDK and Software (https://forum.modalai.com/category/47/voxl-sdk-and-software)
Tags: ros
Posted: 2024-06-25 14:33:16 UTC by Judoor 0
Replies: 3 · Views: 864

## Judoor 0 · 2024-06-25 14:33:16 UTC

Hi,
I'm on the starling2 with sdk-1.3.
I tried to follow the tutorial to install mpa_to_ros2 but at the end I can't run the mpa_to_ros2 node.

First I installed ros2 on the voxl2, then I built the mpa_to_ros2 package on qrb5165 emulator
(I did it with master branch and dev branch)
And finally run ./deploy_to_voxl.sh then when running 
ros2 launch voxl_mpa_to_ros2 voxl_mpa_to_ros2.launch
I've got this error message :
```
[INFO] [launch]: All log files can be found below /opt/ros/foxy/log/2024-06-24-16-50-13-486942-m0054-9328
[INFO] [launch]: Default logging verbosity is set to INFO
Task exception was never retrieved
future: <Task finished coro=<LaunchService._process_one_event() done, defined at /opt/ros/foxy/lib/python3.6/site-packages/launch/launch_service.py:226> exception=InvalidLaunchFileError('',)>
Traceback (most recent call last):
  File "/opt/ros/foxy/lib/python3.6/site-packages/launch/launch_service.py", line 228, in _process_one_event
    await self.__process_event(next_event)
  File "/opt/ros/foxy/lib/python3.6/site-packages/launch/launch_service.py", line 248, in __process_event
    visit_all_entities_and_collect_futures(entity, self.__context))
  File "/opt/ros/foxy/lib/python3.6/site-packages/launch/utilities/visit_all_entities_and_collect_futures_impl.py", line 45, in visit_all_entities_and_collect_futures
    futures_to_return += visit_all_entities_and_collect_futures(sub_entity, context)
  File "/opt/ros/foxy/lib/python3.6/site-packages/launch/utilities/visit_all_entities_and_collect_futures_impl.py", line 45, in visit_all_entities_and_collect_futures
    futures_to_return += visit_all_entities_and_collect_futures(sub_entity, context)
  File "/opt/ros/foxy/lib/python3.6/site-packages/launch/utilities/visit_all_entities_and_collect_futures_impl.py", line 38, in visit_all_entities_and_collect_futures
    sub_entities = entity.visit(context)
  File "/opt/ros/foxy/lib/python3.6/site-packages/launch/action.py", line 108, in visit
    return self.execute(context)
  File "/opt/ros/foxy/lib/python3.6/site-packages/launch/actions/include_launch_description.py", line 130, in execute
    launch_description = self.__launch_description_source.get_launch_description(context)
  File "/opt/ros/foxy/lib/python3.6/site-packages/launch/launch_description_source.py", line 84, in get_launch_description
    self._get_launch_description(self.__expanded_location)
  File "/opt/ros/foxy/lib/python3.6/site-packages/launch/launch_description_sources/any_launch_description_source.py", line 53, in _get_launch_description
    return get_launch_description_from_any_launch_file(location)
  File "/opt/ros/foxy/lib/python3.6/site-packages/launch/launch_description_sources/any_launch_file_utilities.py", line 56, in get_launch_description_from_any_launch_file
    raise InvalidLaunchFileError(extension, likely_errors=exceptions)
launch.invalid_launch_file_error.InvalidLaunchFileError: The launch file may have a syntax error, or its format is unknown
```

I also tried installing mpa_to_ros2 by running *apt-get install voxl-mpa-to-ros2*

But in the end the result was the same.

Am I missing something ? 

Which tutorial am i suppose to follow ?

Julien

## Reply by Zachary Lowell 0 · 2024-06-25 15:29:42 UTC

It is not a launch but a ros2 node itself - should just be `ros2 run voxl_mpa_to_ros2 voxl_mpa_to_ros2`, no launch script.

Zach

## Reply by Judoor 0 · 2024-06-25 16:40:26 UTC (in reply to Zachary Lowell 0)

@Zachary-Lowell-0 said in [Error when launching mpa\_to\_ros2](/post/17892):
> ros2 run voxl_mpa_to_ros2 voxl_mpa_to_ros2

I've got 
"No executable found"
when doing this command

Julien

## Reply by Judoor 0 · 2024-06-26 07:54:59 UTC (in reply to Zachary Lowell 0)

@Zachary-Lowell-0 well it work now!
I found these lines on another thread of the forum:

    sudo apt-get install voxl-ros2-foxy
    sudo apt-get install voxl-mpa-to-ros2
    voxl-configure-mpa-to-ros2
    source /opt/ros/foxy/mpa_to_ros2/install/setup.bash
    export ROS_HOME=/opt/foxy
    ros2 run voxl_mpa_to_ros2 voxl_mpa_to_ros2_node

And everything worked first time ! So please put these line directly on the documentation cause I lost so much time with this install !