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Map Overlapping

asked 2022-06-13 06:09:11 -0500

Os7 gravatar image

updated 2022-06-13 14:15:59 -0500

Hello all I am facing an issue when trying to navigate, i am following the Nox_project which uses gmapping while navigating, when i try to build a map using gmapping the map keeps getting Overlapped, i checked the odom by moving the robot in rviz 1 meter and in real life and rotating the robot on rviz and in real life and they matched so I don't thing its an odometry problem thats the only problem i am facing as when i try the navigation stack the robot planes a goal in a right way but the map keeps changing on it making it creating a new plan so could there be a problem in gmapping other than odometry for over lapping ?

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answered 2022-06-13 09:31:14 -0500

Joe28965 gravatar image

You could try cartographer instead (or maybe hector slam). I'm about 85% sure I know what you mean (if you can, edit the post to add an image of your map).

Your odometry isn't perfect. Driving forward isn't too difficult. If you want a real test, drive around for about 3-4 minutes and then go back to your original point. Theoretically your odom and base_link should overlap again, once you're back at your starting point. You'll probably see that this isn't the case.

Gmapping doesn't deal well with this. Cartographer, on the other hand, creates a lot of small maps and tries to stitch them together (basically how the panorama function on your phone works).

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I see, i have a motor which is faster than the other motor but not so much do you think that is what causing the issue ? Of course its a differential drive robot

Os7 gravatar image Os7  ( 2022-06-13 14:13:44 -0500 )edit

You mean that it's not driving in a straight line? In that case, it is definitely the problem.

Joe28965 gravatar image Joe28965  ( 2022-06-14 01:11:40 -0500 )edit

Yeah it drifts a small bit , will try to solve it and check again

Os7 gravatar image Os7  ( 2022-06-14 01:18:01 -0500 )edit

Then that will be the reason. Gmapping won't be able to deal with that.

Joe28965 gravatar image Joe28965  ( 2022-06-14 06:36:51 -0500 )edit

Hello , its me again :) i fixed the robot movement for the most part but used hector slam at the end which worked perfectly, however when i try to navigate the robot can go to some goals without problems but sometimes the laser sensor readings drifts away from the map make the goal totally different in the real map but the same goal in rviz any idea how to solve this or what is causing this

Os7 gravatar image Os7  ( 2022-06-19 06:40:25 -0500 )edit

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Asked: 2022-06-13 06:09:11 -0500

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Last updated: Jun 13 '22