cartographer-project / cartographer

Cartographer is a system that provides real-time simultaneous localization and mapping (SLAM) in 2D and 3D across multiple platforms and sensor configurations.
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What determines how many nodes are added to a trajectory? #1824

Open jotadepicas opened 3 years ago

jotadepicas commented 3 years ago

Hi, I'm testing cartographer using the Deutsches Museum public bag. I'm trying different Lua settings and checking how it affects the mapping process, etc.

What I notice is that, no matter what configuration I change (whether it's sampling ratios, publish frequencies, accumulated range data for submaps, voxel filter size, motion filter settings, etc, etc), the amount of points in the trajectory seems to be always the same. Take for example this screenshot taken from Rviz:

image

What I get from this image is that every intra-submap contraint in gold/yellow for submap 0, goes from the coordinates origin (0,0) to each and every node in the trajectory for this submap. This amount of nodes, and the consequent amount of constraints, seem to remain invariant no matter what configuration I change.

Is it because it depends purely on range scan frequency (which is constant because I'm replaying a bag)?

What controls when/if a node is added to a trajectory?

Thanks!