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Where can I get TransformStamped values?

I am quite new to ROS and I am creating a new frame "map" as I am using mapserver to publish map and also creating a tf2 from map to odom, which is required for the localization. So the first step, is to create a TransformStamped object with details filled in. The header.frameid and header.childid is obivious, map and odom, but where can I obtain the transform values? When I have included amcl package and r`un rosrun tf tfecho map odom` I got these results and I wonder where can I get them?:

 At time 13.558
- Translation: [0.013, -0.002, 0.000]
- Rotation: in Quaternion [-0.000, 0.000, 0.000, 1.000]
            in RPY (radian) [-0.000, 0.000, 0.000]
            in RPY (degree) [-0.000, 0.001, 0.010]

Asked by stevemartin on 2018-10-24 04:24:58 UTC

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see related: #q306575

Asked by mgruhler on 2018-10-25 01:46:48 UTC

@stevemartin: you may want to review REP-105. That should make the relationship between all these frames a little clearer.

@mgruhler is correct: those values are not "special", they are the result of localisation of your robot in the map frame.

Asked by gvdhoorn on 2018-10-25 02:44:51 UTC

Answers

Well, actually it is the localization node (i.e. amcl, for example) which produces the transfrom from map to odom. So this is where those values come from.

If you want to do localization yourself, your code needs to produce those values...

Asked by mgruhler on 2018-10-25 01:42:26 UTC

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