Re: misalignment from tango multi session

Posted by matlabbe on
URL: http://official-rtab-map-forum.206.s1.nabble.com/misalignment-from-tango-multi-session-tp5046p6011.html

Hi,

CPU is the most important thing. There are no optimizations done on GPU for scan matching. GPU is mostly used only for visualization/rendering the map in real-time. A bigger GPU will make the visualization smoother and also details can be increased (more points to show). Same for RAM, larger maps can be visualized. If visualization is done remotely, a GPU is not needed. A SSD is always nice too, as the database is recorded on hard-drive by default. If you have a lot of RAM, you may even keep the whole database in memory instead of hard drive (parameter DbSqlite3/InMemory=true). The disadvantage is that if the computer crashes, there is no way to recover the data (when database is on disk, it is possible to recover the database after a system crash, see "rtabmap-recovery" tool).

For the configuration, it is difficult to say. Sure faster is better in general (to avoid having 100% CPU usage on one core). However, the quality may not be higher depending on the speed of the robot/scanner. For example, icp done in 20 ms at 5 m/s would give same quality than icp done in 100 ms at 1 m/s. Well, depending what is the frame rate of the lidar, you may get better results when moving slower anyway to avoid displacement errors inside a single scan during its rotation. If you can increase the rotation rate of the lidar, I recommend to do so.

cheers,
Mathieu