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Scan topic for mapping

asked 2012-07-04 05:50:21 -0500

allenh1 gravatar image

updated 2012-07-06 05:48:40 -0500

I'm having trouble with mapping... I have both the laser scan and odometry from a bagfile. When I run the laser scan trough a node (doesn't change any data, just converts to a pointcloud) and convert back to a laserscan with poincloudtolaser, it will not map from the new topic.

I'm sure this has something to do with the base_link or some frame_id thing, but I have no idea how to set this up... Any help?

The published scan has a different laser topic. It is /laserOut/filtered (again, no filtering yet). So, I run gmapping with the following:

rosrun gmapping slam_gmapping _particles:=100 _linearUpdate:=0.1 _angularUpdate:=0.1 scan:=/laserOut/filtered

This accounts for the update interval and points at the topic to listen to. Gmapping is not having trouble with scan matching. It scores like it does normally. The only difference is the fact that it does not update the map after.

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answered 2012-07-04 06:09:41 -0500

Hi, normaly the TF (or as you called it frame_id think ;-) ) for a laser scan message is by default "/laser" and the topic name is "/scan". With

rostopic list

you can check if the topic name "/scan" is available. If yes the just check by

rostopic echo /scan

if the header of the message contains the correct default frame_id. Alternatively you can also try


and check the results.

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All is as it should be there... What would cause GMapping to scan match and score highly, but not update the map?

allenh1 gravatar image allenh1  ( 2012-07-05 07:37:24 -0500 )edit

As far as i remember was there a parameter for setting up the map updated ratio, i.e. the parameter after how many meters or change in degree shall the map be republished. May this helps.

tlinder gravatar image tlinder  ( 2012-07-05 08:11:54 -0500 )edit

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Asked: 2012-07-04 05:50:21 -0500

Seen: 896 times

Last updated: Jul 06 '12