Slam drift error

Hello i succesfully managed to run the fantastic gazebo simulation of the rosbot on the ready to go virtual machine and after a while i was having fun navigating the robot around and building the map i found out that probably there is some error accumulating/various over time on the robot position tracking and map construction because some building were covered as if they were absent as you can see from the printscreen i will try to attach. Is that normal for this SLAM navigation and map construction, like an error that should be corrected by using some software enhancement like self matching etc. or I am badli interpreting the plot?
Also I would like to better see the map, it seems that the map scan is completely squeezed on the z=0 plane, how to view it more solid 3D in space??
Thanks a lot for help

I don’t know how to attach a printscreen here

Hello Alessio_Stella,

Map in the example is created based on laser scanner measurements. Both laser scans and generated map are two dimensional. Map cells can have three states:

  1. Free, marked with white
  2. Occupied, marked with black
  3. Unknown, marked with grey

To add your printscreen, use “upload” button from post edit toolbar, then choose appropriate image file.