# Voxl_mpa_to_ros

Source: https://forum.modalai.com/topic/1391/voxl_mpa_to_ros
Category: General Questions (https://forum.modalai.com/category/2/general-questions)
Posted: 2022-09-27 22:23:56 UTC by gauravshukla914
Replies: 7 · Views: 1806

## gauravshukla914 · 2022-09-27 22:23:56 UTC

For some reason, when I do - 
roslaunch voxl_mpa_to_ros voxl_mpa_to_ros.launch

it doesn't seem to work fully. Here's the output - 

```
voxl:~$ roslaunch voxl_mpa_to_ros voxl_mpa_to_ros.launch 
... logging to /home/root/.ros/log/7da4c736-3eb2-11ed-b715-18473db1be57/roslaunch-apq8096-3745.log
Checking log directory for disk usage. This may take awhile.
Press Ctrl-C to interrupt
Done checking log file disk usage. Usage is <1GB.

started roslaunch server http://localhost:57891/

SUMMARY
========

PARAMETERS
 * /rosdistro: indigo
 * /rosversion: 1.11.21

NODES
  /
    voxl_mpa_to_ros_node (voxl_mpa_to_ros/voxl_mpa_to_ros_node)

auto-starting new master
process[master]: started with pid [3764]
ROS_MASTER_URI=http://localhost:11311

setting /run_id to 7da4c736-3eb2-11ed-b715-18473db1be57
process[rosout-1]: started with pid [3777]
started core service [/rosout]
process[voxl_mpa_to_ros_node-2]: started with pid [3780]

MPA to ROS app is now running

Found new interface: qvio_overlay
Found new interface: stereo
Found new interface: tracking
Found new interface: imu1
Found new interface: qvio

```
And it stops after this. When I do rostopic list on the other terminal, it says unable to communicate with the Master. My bashrc file is correct with correct ROS_MASTER_IP and ROS_IP. Even rqt says the same thing. I plan to see the output of the camera in the rqt viewer.

## Reply by gauravshukla914 · 2022-09-28 23:37:36 UTC

Can someone help me with this? Thanks!

## Reply by tangotoo · 2022-09-29 00:23:28 UTC

I don't know if its related to your problem, but I had a lack of communication issue between voxl-vision and my PX4 and it was due to an additional process, voxl-mavlink-server not running.  You may want to check if there are any other supporting processes you need running first in order to bring up ROS.  I'm not a ROS user, so I can't help too much in that regard.

## Reply by gauravshukla914 · 2022-09-29 17:22:25 UTC

@modaltb @Ed-Sutter @tom @Alex-Gardner anyone?

## Reply by Dong Liu · 2022-09-30 16:35:22 UTC

@gauravshukla914 

Don't know it is related. But I had the same experience. You can't rostopic list because the ROS_MASTER_URI and ROS_IP are not set correctly.

There is file /home/root/my_ros_env.sh which defines these two variables. Need to be changed to reflect the real values.

Dong

## Reply by gauravshukla914 · 2022-09-30 17:58:15 UTC

@Dong-Liu yes that's correct. Everytime a master ip or ros ip changes, I make sure to give the corrects IPs in the bachrc file and source it. This is not the issue, but thanks for the suggestion though!

## Reply by gauravshukla914 · 2022-10-03 15:46:58 UTC

This is solved. I'm made to source my_ros_env.sh file everytime before launching the mpa file. But this never used to happen before. Anyway for now its working by sourcing the my_ros_env.sh everytime. Thanks all!

## Reply by Dong Liu · 2022-10-04 05:16:10 UTC (in reply to gauravshukla914)

@gauravshukla914 I also noticed it. Somehow on the drone's ROS indigo system. roslaunch voxl_mpa_to_ros voxl_map_to_ros.launch won't honor the existing ROS_MASTER_URI, it always source ROS_MASTER_URI etc from my_ros_env.sh