Pure localization - Strange behavior with residuals

[LukasBergs]

Hi Cartographer Team,

We have been using Cartogrpaher for our project for almost a year now and really love the software. At this point a big thank you for providing the code!

Unfortunately, we have reached a point where we are stuck with the following issue:

We are using Cartographer for pure localization. In certain cases, we see a jump in localization which we can neither explain nor reliably reproduce. Every time a jump occurs we see big "inter residuals, different trajectory" in rviz. Usually these residuals are quite small and barely visible. Only when an incorrect jump occurs, they are big and clearly visible. It does not look like these jumps occur due to incorrect point cloud matching. Most of the time (I am not sure if even every time) the constraint builder gets a score of exactly 90.0% when incorrect jumps occure.

You can find my lua file, a picture and a video showing the strange behavior here:
https://drive.google.com/drive/folders/1RZMLzlye5Q0CM8TuA5ndxgQC7MDofluZ?usp=sharing

Can someone explain what these residuals do, how they are created and why these incorrect jumps occure? Can these jumps somehow be prevented by changes in the .lua file? Since we are using an initial pose when starting pure localization mode a possible workaround would also be to prevent jumps bigger then x meters. Is that possible?

If you need more data or information feel free to ask!

Thanks a lot for your time, Lukas