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Data loss between publisher and subscriber

asked 2017-10-03 17:15:12 -0500

_nobot.enter
5 ●2 ●5 ●5

Hello

I was running ROS package with one publisher and subscriber in below link. https://github.com/oroca/oroca_ros_tu...

Basically, publisher sends a number (add 1 every loop) and subscriber gets it.

So, I run subscriber first, then run publisher in a different terminal.
Then I could see that there was a loss.

Publisher starts with 0, but Subscriber gets from 3.

Is this normal? Is this solvable?

Thank you in advance.

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answered 2017-10-05 04:21:17 -0500

Stefan Kohlbrecher

24361 ●173 ●299 ●444 https://www.energy-rob...

When a publisher is created, there is some setup performed "behind the scenes", such as registering with the ROS Master and potential subscribers. This means that when one publishes immediately after creation of the publisher, messages might not actually get out because the Publisher wasn't "ready" yet. See for instance also other Q/As such as this one. Pretty sure that adding a sleep here in line 13 would fix the issue.

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Thanks Stefan Kohlbrecher :D

_nobot.enter ( 2017-10-05 13:50:17 -0500 )edit

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Asked: 2017-10-03 17:15:12 -0500

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Last updated: Oct 05 '17

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