Compact Storage Facility

There exists a business in which storage-space is rented. For decades they tended to occupy a significant chunk of landscape, to allow easy ground-level access to each storage unit (various sizes available) of the facility. Recently I've seen some multi-storey storage facilities getting built, so I'm guessing they incorporate very powerful elevator systems, for moving large amounts of stuff easily between ground level and the level of some particular storage unit.

Even the multi-storey facilities still occupy more landscape than necessary, however, and this Idea is about a way to shrink them significantly (or to put a lot more units into the same space as before). It depends partly upon a lot of statistical data about how many of the storage units in a typical facility are ever accessed at the same time....

First, we need to select a size for a storage unit. A common size is about 3 meters x 3 meters of floor area. For the purposes of this Idea, we shall offer 3 sizes, a 2x2- meter space, a 3x3-meter space, and a 4x4-meter space. All the units are the same height --let's go with 3 meters. This facility is 3 storeys high, with all the storage units on each floor being the same size.

Each storage unit is literally a box, strongly built. There are doors on all four of its walls, and each box is move- able. It has a bunch of caster wheels on the bottom, and an RFID chip on top, along with means of being grabbed (by ceiling-mounted machinery) and moved.

Now see the link, for a classic puzzle/game. Imagine all the squares EXCEPT ONE occupied by a storage-unit box, and an aisle completely surrounding the overall square.

Remember what I said earlier, about how many of the units are ever simultaneously accessed? A 5x5 array of move- able storage-unit boxes has 24 total in that array, with 8 on the inside and 16 on the outside. If as many as 2/3 of all the units are ever accessed simultaneously, this array would be fine.

However, if all the units are simultaneously ever accessed to a lesser extent, then a 6x6 array (or more) might be preferred. it will contain 35 move-able storage-unit boxes, of which 15 would be on the inside and 20 on the outside (4/7 of them accessible at once). A 7x7 array would hold 48 move-able units, with 24 on the inside and 24 on the outside (50% accessible simultaneously). An 8x8 array would hold 63 units, with 35 on the inside and 28 on the outside (4/9 accessible simultaneously). Historical usage statistics are extremely critical to this Idea!

Note that where-ever one's particular rented storage unit might be, the "puzzle" consists of finding the shortest path for moving that unit to the outside edge of the array. The renter can be told where, along the outside aisle, to go to await the arrival of the storage box. I suspect the corner- locations will always be prime destinations (never want to shift any box getting accessed!!). I'm sure computers can solve that simple a puzzle with ease.

(Technically, there will probably always be one less than the maximum of simultaneously-accessible outer boxes, due to the need to be able to shift at least two of them, to move a desired box to the outside. If the array had two holes in it instead of one, though, then only shifting a corner box becomes problematic to its neighbors. Perhaps the corner-boxes should be permanently fixed in place, and never moved? They would only need 2 doors each, but renters could be charged more, for the convenience of always knowing where to go to access their stuff.)

When someone closes the door to the storage unit, the system can then know that the renter is done, and that space along the surrounding aisle is now available to a different renter. The purpose of the RFID chips is to make sure the units can be re-identified if a complete power failure happens to cause location-data to be lost.