Indoor navigation maps for humans and indoor navigation and positioning maps for autonomous robots and drones or for 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. in order for the humans to localize themselves inside the building and find the way towards the points of interest. The map for humans is just a basic picture
For robots – it is a complete indoor positioning system – not a picture – with stationary beacons (anchors), their coordinates, underlying communication between the stationary and mobile beacons (tags). Thus, a 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)
One or more submaps – they are similar to cells in cellular networks – each of them cover its own territory. Submaps consists 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 in their service zones, even if they could cover more. It is done in order to avoid ambiguity and “minority reports” from different submaps
Handover zones – a relatively thin areas where the service zones are overlapping between the neighboring submaps. The handover zones are needed in order to smoothly hand over tracking from one submap to another
Floorplan/substrate is visual, graphical representation of your indoor map. It is not used by the system for indoor tracking, but it is easy for people to see the trackable objects against typical visuals clues used by humans: doors, entries, windows, corners, etc.
The easiest practical way to get the floorplan – to use an evacuation plan. Real construction plan, if available, is great as well.
Again, the graphical floorplan is required only for human users and it is not required for the indoor positioning system. The system relies on the coordinates of the stationary beacons and absolute distances to them
See a practical example of how to create indoor navigation map for a warehouse/assembly plan with a floorplan, map of beacons, multiple submaps, multiple service and handover zones