Cartographer_ros: Documentation: Tuning guide

[ojura]

It would be nice if there was a comprehensive tuning guide with a little more in-depth explanation of the parameters available via Lua configuration files, implications what happens when they are changed, and recommendations for making adjustments (e.g. what to do if Cartographer fails to recognize loop closures because they end up being too far away). Although this would require some effort, I think it would be beneficial in long term, because the volume of tuning-related issues on Github should be decreased, saving you time.

Edit by @SirVer: Added checkboxes
Edit by @gaschler: Additional checkboxes

• [x] Tuning guide for slipping in local SLAM.
• [ ] Screencaps for local SLAM
• [ ] Tuning of loop closure.
• [ ] Explanation of Huber scale.
• [x] Tune for low latency (real time).
• [x] Tune for pure localization.

[ojura]

Some notes: A larger Huber scale adjusts the Huber loss function so that outliers have a larger effect. The parameter should be tuned so that it encompasses only inlier constraints.

Increasing the loop closure search window: see SPARSE_POSE_GRAPH.constraint_builder.fast_correlative_scan_matcher.linear_search_window and SPARSE_POSE_GRAPH.constraint_builder.max_constraint_distance in cartographer/configuration_files/sparse_pose_graph.lua.

[msy22]

What is the unit for the SPARSE_POSE_GRAPH.constraint_builder.max_constraint_distance parameter? Is it meters? pixels? voxels?

[wohe]

Meters. Similar with other distances.

[msy22]

Great, thanks for the clarification!

[MichaelGrupp]

Closing, we have a tuning guide in the docs. Extension proposals via PRs are always welcome :+1: