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Node doesn't receive message, but rostopic list/info sees it [closed]

asked 2016-02-18 15:31:16 -0500

Pengatom gravatar image

updated 2016-02-18 15:48:51 -0500

I've modified the turtlesim tutorial to control some servos from a ps3 controller, and everything works fine when everything is running from my laptop. Now I want to move the part/file that actually do the moving of the servos over to a RPi.

I've added

export ROS_MASTER_URI=http://Yoda.local:11311

to the .bashrc on both nodes.

rostopic list/info/type displays the same info on both laptop and RPi, but when I try to get any actual data out, the RPi doesn't receive anything on rostopic echo/hz

I've tried running

rostopic pub -r 10 /robonova3/cmd_vel geometry_msgs/Twist '{linear: {x: 0.1, y: 0.0, z: 0.0}, angular: {x: 0.0,y: 0.0,z: 0.0}}'

on both machines, but its only picked up locally, not by the other machine...

Any suggestions?

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Closed for the following reason the question is answered, right answer was accepted by Procópio
close date 2016-02-25 03:53:35.530478


Have you also set the ROS_IP on both computers?

NEngelhard gravatar image NEngelhard  ( 2016-02-18 15:54:43 -0500 )edit

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answered 2016-02-18 15:59:04 -0500

This can happen when ROS_IP or ROS_HOSTNAME (only one of the two needed) are not set correctly on both machines. See also lEnvironmentVariables or this Q/A, Searching for "ROS_IP" or "ROS_HOSTNAME" here or on google should also provide sufficient info to fix this issue.

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Voila! Thanks Should've been better explained that this is needed. In the tutorial it's only mentioned as something to add if one cannot ssh to the machine - which I could...

Pengatom gravatar image Pengatom  ( 2016-02-19 07:31:16 -0500 )edit

you are welcome to edit the wiki to better explain that ;)

Procópio gravatar image Procópio  ( 2016-02-25 03:17:46 -0500 )edit

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Asked: 2016-02-18 15:31:16 -0500

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Last updated: Feb 18 '16