# problems installing voxl-mpa-to-ros2

Source: https://forum.modalai.com/topic/3920/problems-installing-voxl-mpa-to-ros2
Category: VOXL SDK and Software (https://forum.modalai.com/category/47/voxl-sdk-and-software)
Tags: ros
Posted: 2024-11-07 22:19:53 UTC by LR
Replies: 5 · Views: 1452

## LR · 2024-11-07 22:19:53 UTC

Hello,

I'm following this guide https://docs.modalai.com/ros2-installation-voxl2/ to build the voxl-mpa-to-ros2 pkg and push it into VOXL2. I'm facing some problems with the instructions, in detail, I succeeded into creating the qrb5165-emulator image, then I can install the dependencies with './install_build_deps.sh qrb5165 dev', but when I try to run the build.sh file the voxl_msgs pkg fail to compile. Below the error I obtain. What am I doing wrong?

![error_mpa_ros2.png](https://forum.modalai.com/assets/uploads/files/1731017952119-error_mpa_ros2.png)

## Reply by Zachary Lowell 0 · 2024-11-08 18:18:53 UTC

@LR Hi going to look into this - for now can you just install the deb as is via `apt-get install voxl-mpa-to-ros2` ?

Will let you know if I run into the same error.

## Reply by jmltt · 2024-11-09 16:43:47 UTC

This is the same build error I ran into (see here https://forum.modalai.com/topic/3908/voxl-px4-and-voxl-mpa-to-ros2-message-compatibility-and-build-issues)

It turned out to be a issue with the version of empy installed when running install_build_dependencies (specifically in python3 -m pip install colcon-common-extensions lark)

I resolved it by downgrading empy after running the install build dependencies script in the docker container

```
python3 -m pip uninstall -y empy
python3 -m pip install empy==3.3.4

```

## Reply by Zachary Lowell 0 · 2024-11-11 16:23:03 UTC

Yep @jmltt @LR I merged in an MR this morning that will capture this error for empy not being compatible - thanks for the find @jmltt !!!

## Reply by LR · 2024-11-14 23:03:14 UTC (in reply to Zachary Lowell 0)

@Zachary-Lowell-0 Hi, thank you for your response! I've tried to installed it directly but when I try to access it with *ros2 run voxl_mpa_to_ros2 voxl_mpa_to_ros2* it doesn't find the node, I also checked under *opt/ros/foxy/mpa_to_ros2/install* and the package is not there...![support3.png](https://forum.modalai.com/assets/uploads/files/1731625042823-support3.png) 
I tried again to install it on the docker container with what @jmltt told me and now I have this problem
![support4.png](https://forum.modalai.com/assets/uploads/files/1731625175801-support4.png) 
Lastly I tried also to install *voxl_mpa_to_ros* for melodic but in this case the package contains just the launch file and not the *voxl_mpa_to_ros_node* so again I cannot call the function
![support5.png](https://forum.modalai.com/assets/uploads/files/1731625352265-support5.png)  

Sorry for all this...

## Reply by LR · 2024-11-15 14:28:26 UTC (in reply to LR)

@LR I removed and reinstalled voxl-mpa-to-ros2 and that is working now, for voxl-mpa-to-ros I still have the same problem