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I am working with the gps-waypoint branch of the ardrone driver. I follow the steps of the website but in the end I always get the same message (''topic [/ardrone/navdata_gps] does not appear to be published yet'') when I try to see what is being published on this topic. I already checked that the parameter "_enable_navdata_gps" is set to true.

I have no idea what the problem is. The firmware of the GPS module is the last one and I am using ROS Indigo on Ubuntu 14.04 .

Thanks in advance.

Originally posted by JCUAV on ROS Answers with karma: 41 on 2015-10-08

Post score: 0

Original comments

Comment by Mani on 2015-10-08:
How do you enable navdata_gps? Could you please specify the exact command you use to execute the driver?

Comment by JCUAV on 2015-10-09:
$ rosrun ardrone_autonomy ardrone_driver _enable_navdata_gps:=True

I have already found the solution but thanks anyway.


1 Answer 1


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After using another computer I realized it was some kind of path problem. The first time I used the binary installation for the driver but the GPS branch is intalled from source. Therefore when we ran the package, the path /opt/ros/indigo/share/ardrone_autonomy was followed instead of using the files from the catkin workspace.

What I did is to unistall the ardrone_autonomy driver with the command "$ sudo apt-get --purge remove ros-indigo-ardrone-autonomy".
At this point (after running the driver again), I was able to see "/ardrone/navdata_gps" between the list of topics but when we typed "rostopic echo /ardrone/navdata_gps" we got the message "Cannot load message class for [/ardrone/navdata_gps]. Are your messages built?". The solution to this is to clean the workspace (catkin_make clean),then build it (catkin_make) and finally source the path (source devel/setup.bash).

Hopefully this is helpful.

Originally posted by JCUAV with karma: 41 on 2015-10-09

This answer was ACCEPTED on the original site

Post score: 1

Original comments

Comment by ktiwari9 on 2017-06-17:
Hi @JCUAV, I am still struggling with this. I am on ROS Kinetic running on Ubuntu 16.04. I installed the ardrone autonomy like "$apt-get install ros-kinetic-ardrone-autonomy" and then I sourced the bash file in /opt/ros/kinetic. When I launch the autonomy node, I dont see the GPS topic. Help Plz

Comment by Maureen on 2017-07-03:
so useful!!!


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