No `mavros/local_position/local` Topic

[weiweikong]

I installed mavros by

sudo apt-get install ros-indigo-ros*

and connected with Pixhawk (Stable Firmware) by

roslauch mavros px4.launch

I could get the topics and received data correctly such as imu/data, local_position/pose and local_position/velocity, however, there was no topic named local_position/local. Also, I checked the ROS wiki (http://wiki.ros.org/mavros#mavros.2BAC8-Plugins.local_position), where did not introduce such topic. So I am confused about this topic?

[LorenzMeier]

@vooon Do you still need to arm to get those? It would seem like this should not depend on arming.

[vooon]

@LorenzMeier i'm not sure about publishing rates, but i think question not about "not publishing" issue.

@weiweikong Use rostopic list! And i'm pretty sure you missed ~ symbol, which means private node namespace (/mavros by default).

[weiweikong]

@LorenzMeier @vooon I tried some further test.

mavros without arming the system

• Use roslaunch mavros px4.launch
• Then run rostopic list
• It seems that there was no mavros/local_position/local publishing.

mavros with arming the system

• Arm the system by RC
• Then run rostopic list, still no /mavros/local_position/local. But other nodes receive data smoothly, such as /mavros/local_position/pose, by running

rostopic ehco /mavros/local_position/pose

[weiweikong]

I checked the Pull https://github.com/mavlink/mavros/pull/420, and in master branch, the local_position.cpp has, https://github.com/mavlink/mavros/blob/master/mavros/src/plugins/local_position.cpp#L50-L51, renamed the publish nodes from local_position/local to

local_position = lp_nh.advertise<geometry_msgs::PoseStamped>("pose", 10);
local_velocity = lp_nh.advertise<geometry_msgs::TwistStamped>("velocity", 10);

So, it could be no /mavros/local_position/local topic in current version, no matter installing from master branch from github or using sudo apt-get install ros-indigo-mavros*.

[vooon]

Yes, just use ~local_position/pose.