Re: Depth precision in mapping

Posted by matlabbe on
URL: http://official-rtab-map-forum.206.s1.nabble.com/Depth-precision-in-mapping-tp464p472.html

Hi Kazu,

Yes, this is a limitation of the Kinect. The Kinect v2 has much better depth precision (up to 10-12 meters as I've seen), but less portable than an Xtion Pro Live. It may worth a try depending on your application. Otherwise, you can still filter the depth from the Kinect under 4 meters to have better precision in the map.

Another event that can create multiple layers like you are seeing is if the odometry is poor. If the robot moves toward a dead end and there are some odometry errors in translation, the depth may not be aligned all together. Example: the robot is at 6 meters from the dead end wall, it moves toward it. At first it takes an image of the wall, which is at 6 meters. It moves 3 meters toward the wall but has a big odometry error of 1 meter, so it thinks it moved 2 meters instead. However, the wall is seen at 3 meters in front of the robot instead of 4 meters accordingly to odometry. Well, there will be 1 meter error on the wall cloud (appearing at 5 and 6 meters from the original position).

cheers,
Mathieu