0
$\begingroup$

Rosanswers logo

In gmapping documents http://www.ros.org/wiki/gmapping, and in 5.1.5,5.1.6 says that base_link → odom, and map → odom.

I have try to use map → odom → base_link → base_laser.

  1. I don't know "base_link → odom" is right or "odom → base_link" is right? Why?

  2. What's the transform formula between odom and base_link?

  3. Can I output the transform data(map→odom) from gmapping?

Thank you~


Originally posted by sam on ROS Answers with karma: 2570 on 2011-07-30

Post score: 0

$\endgroup$

1 Answer 1

0
$\begingroup$

Rosanswers logo

  1. odom -> base_link. You are building a tree starting from a fixed frame and going down the attached things.

  2. What do you mean with formula? It should be the robot's motion estimation.

  3. Do you mean output for debugging or generate? For the former use tf_echo (or display in rviz), for the latter: Yes, that's what it's supposed to do.


Originally posted by dornhege with karma: 31395 on 2011-07-30

This answer was ACCEPTED on the original site

Post score: 0


Original comments

Comment by dornhege on 2011-08-01:
I haven't written the package, but I would say that it gets the data from the odom->base_link transform and the motion model is "hardcoded" as gmapping params (instead of using the covariance).

Comment by sam on 2011-07-31:
Why my gmapping node doesn't require /odom? Doesn't Gmapping need to know the position of robot or laser range finder?

Comment by RB on 2013-11-13:
What could be the reasons of empty map.pgm although it's size is 15.3 MB. Now laser messages are properly published and the tf tree looks ok. But no transform from [/GrndTruth] to frame[/map] and no transform from [/base_GrndTruth to frame[/map]. You can view in details http://answers.ros.org/question/94671/error-in-creating-2d-global-map-of-the-environment/

$\endgroup$

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.