Re: RTAB-map only for mapping

Posted by matlabbe on
URL: http://official-rtab-map-forum.206.s1.nabble.com/RTAB-map-only-for-mapping-tp1896p2855.html

Hi,

gmapping should be already refining odometry while mapping (with laser). The problem is that RTAB-Map reconstruction is done in another map representation (graph-based map) than gmapping (which is a particle filter). RTAB-Map cannot know from gmapping when a loop closure is detected or odometry is refined. Well, it can detect that current pose has been corrected, but it cannot know how the whole map has been corrected.

For example, if we set RTAB-Map just in mapping mode without its loop closure detection or its odometry refining, then just subscribe to camera and last estimated pose from gmapping, the maps will correspond until gmapping does a map correction (loop closure, odometry correction). Then from there, the maps (rtabmap map vs gmapping map) will diverge from each other.

If gmapping would maintain a graph of key poses with its map, it would be possible (with some code modifications) for RTAB-Map to subscribe on this graph and update the whole 3D map when gmapping corrects the map, so that maps are always synchronized.

cheers,
Mathieu

cheers,
Mathieu