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RQT_Graph cmd_vel passthrough

asked 2015-06-07 15:16:05 -0600

luketheduke gravatar image

updated 2015-06-07 15:16:31 -0600

Hi All,! I am troubleshooting a robot I am working on and for some reason the twist commands are not getting to the base. On ething I found that I think is out of the ordinary is this: image description Is it normal that /cmd_vel is:

  1. Coming from two different sources into the rostopic node?
  2. Going through the Arduino node?
  3. And that it has that little loop above the /arduino bubble in the arduino node?

Thanks for all your help in advance,


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answered 2015-06-09 12:22:57 -0600

130s gravatar image

updated 2015-06-09 12:51:02 -0600

That diagram you poseted looks like a valid ROS node graph architecture-wise; ROS topic is n-to-n, not 1-to-1. See other threads for example (1, 2) for more concept.

Depending on your application, however, your configration can be problematic since all topics are published under the same name cmd_vel. You could publish the same topic type (called msg in ROS) under different names so that the subscribers can differentiate what they really need.

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When I loaded rqt_graph later it looked normal again. Thanks for your help! luketheduke

luketheduke gravatar image luketheduke  ( 2015-06-14 14:42:57 -0600 )edit

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Asked: 2015-06-07 15:16:05 -0600

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Last updated: Jun 09 '15