Indoor navigation maps for humans and indoor navigation and positioning maps for autonomous robots and drones or precise tracking of people or forklifts or other mobile objects are different things:
For humans – a basic 2D or 3D visualization of the building, warehouse, or plant with visual clues such as doors, halls, windows, etc., to localize themselves inside the building and find the way toward the points of interest. The map for humans is just a primary picture.
For robots – it is a complete indoor positioning system – not a picture – with stationary beacons (anchors), their coordinates, and underlying communication between the stationary and mobile beacons (tags). Thus, the correct wording would be “an indoor navigation map of stationary beacons” instead of just “indoor navigation map” because the majority of real-life indoor navigation and positioning systems rely on stationary beacons using different technologies (ultrasound, ultra-wideband radio, BLE, or WiFi).
Each submaps, similar to cells in cellular networks, covers its territory. Submaps consist of 1, 2, 3, or 4 stationary beacons for 1D, 2D, or 3D tracking.
Service zones – directly defined zones of responsibility for each submap. Submaps track only their service zones, even if they could cover more. It avoids ambiguity and “minority reports” from different submaps.
Handover zones – a relatively thin area where the service zones overlap between the neighboring submaps. The handover zones are needed to smoothly handover the track from one submap to another.
Floorplan/substrate is a visual, graphical representation of your indoor map. The system does not use it for indoor tracking, but it is easy for people to see the trackable objects against typical visual clues humans use: doors, entries, windows, corners, etc.
The easiest practical way to get to the floorplan – is to use an evacuation plan. An actual construction plan, if available, is excellent as well.
Again, the graphical floorplan is required only for human users and is not necessary for the indoor positioning system. The system relies on the coordinates of the stationary beacons and their absolute distances to them.
See a practical example of creating an indoor navigation map for a warehouse/assembly plan with a floorplan, map of beacons, multiple submaps, and numerous service and handover zones.
Precise tracking of workers on a plant.