Costmap
Used in nav2. I first interacted with costmaps working at Enlighted.
I am not super familiar with costmaps, https://github.com/ros-planning/navigation2/blob/1efc96c3aa1b80d4926238238b56d45a9d7a8993/doc/design/CostmapFilters_design.pdf
- Inflation layer: http://wiki.ros.org/costmap_2d/layered