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TF Error between two machines

Hello,

I am working with two machines together. One for a manipulator("melodic" version) and the second for the autonomous platform("kinetic" platform). In the first computer (It is the master) I run the urdf of all the system and the urdriver for the manipulator. In the second machine I run RTABmap and robotlocalization pkg. When I look in Rviz I see that there is an error when the fixed frame is "map" or "odom" (these are the only 2 frames which published in the second machine). There is no link between the whole frames Although in rqt it looks fine. If I change the fixed frame to another frame like "basefootprint) it is look fine. In addition, when I run "tfmonitor" between "map" and the highlighted frames in Rviz(see image) I have the same error.

I added some images and I will glad if someone can give me some suggestions for that.

Thanks, Aviad

https://ibb.co/k2mgTbJ

https://ibb.co/ZX6jbQ1

https://ibb.co/P563CMk

Asked by Aviad on 2019-11-19 04:36:20 UTC

Comments

Have you propperly set ROS_MASTER_URI and ROS_HOSTNAME on both machines ?

Asked by Delb on 2019-11-19 05:01:07 UTC

Hi, I seted ROS_MASTER_URI well but I did not set ROS_HOSTNAME at all. I can see the topics which published between the computers. Maybe the ROS_HOSTNAME is the problem?

Asked by Aviad on 2019-11-19 05:16:55 UTC

It could indeed create issues, you have to set ROS_HOSTNAME or set ROS_IP for each machine with their corresponding ip adress.

Asked by Delb on 2019-11-19 05:27:35 UTC

I have ROS_IP for both machines. So, if I understand you I don't need to set ROS_HOSTNAME too. Right?

Asked by Aviad on 2019-11-19 05:41:34 UTC

Yes ROS_HOSTNAME and ROS_IP are mutually exclusive. Have you tried running roswtf while running the program ? It can detect TF issues (doc link)

Asked by Delb on 2019-11-19 06:08:39 UTC

If you look at the rqt_graph, the timestamps for map and odom are like 160 seconds in the future. Try synchronizing the clocks between the machines (ntpdate).

Asked by matlabbe on 2019-11-19 08:33:05 UTC

@Aviad: please attach your screenshots directly to this question.

I've given you sufficient karma for that.

Asked by gvdhoorn on 2019-11-20 03:17:31 UTC

Answers