Using multiple lidars with rtabmap

Posted by GiladB on
URL: http://official-rtab-map-forum.206.s1.nabble.com/Using-multiple-lidars-with-rtabmap-tp10172.html

Hi,
I'm interested in the possibility to integrate 2 lidars into rtabmap to improve localization accuracy.
I have two 2D-lidars on a robot, each with close to 270 degrees FOV that together cover nicely the full 360 degrees surrounding of the robot.
I try to understand how it will be best to integrate it to rtabmap if I choose to enable the subscribe_scan feature.

These are the 3 options that I came up with:
1) Integrate just 1 lidar
2) publish both scans under the same topic. Each have a different frame_id and min/max angle values so maybe it will be good enough for rtabmap to understand how to use it (Probably not how it was planned to be used, but maybe it is robust enough?)
3) Merge the two scans under a virtual scan with a virtual frame_id. in this case, since the frame_id is not the actual lidar's frame_id, I will need to define some inaccurate min/max range values which I don't know if they will affect rtabmap. Another possible issue could be the fact that each lidars are working in 33hz and they are not synced (Maybe if the robot moves rapidly, it will do more harm than good?)

I would love to hear what you think.

Thanks,
Gilad