To all those snidely commenting about trains or rail: Do you think that Japan, of all places, is not familiar with railways? The article states that this is for palletized or small-package loads. Give them some credit.
It's what people call a "gadgetbahn": something that does the job of a railway, but not using railway technology, thereby introducing a whole load of unproven tech. This looks great in the AI renders but then turns out to make it infeasible.
> Currently the world's longest conveyor belt is 61km
100km. The article you linked used miles.
That one transfers the load between different sections of its length. The longest conveyer that does not transfers the load is 31km at Boddington Bauxite Mine in Australia.
> This is five times longer [...]
Does that actually introduce any new technical difficulties?
Suppose I needed a 2m x 1m table. I could get some 2m long boards and put enough in parallel to get my 1m width. I could put 1m boards perpendicular to those underneath at the ends and nail the 2m long boards to them. Then add legs at the 4 corners and I have a table.
Then I need a 5m x 1m table. I could take the same approach except using 5m boards instead of 2m boards. I might need to nail some more perpendiculars in the middle part of the table or maybe add some legs in the middle.
As I need longer and longer tables that approach keeps working up to maybe 10m. I don't think my local source of boards has boards longer than that.
So if I need a 30m x 1m table I need a new approach. I need to figure out something that doesn't require single boards that span the whole thing. It has to be limited to boards I can reasonably get. Let's say I figure out how to make that 30m x 1m table using no boards longer than 4m.
At that point I expect that I'd be able to build tables of any greater length by just doing whatever I did in the middle of the 30m table but doing more of that.
I'd expect that a similar thing happens when you build a 100km long conveyor. The specific project was "build a 100km long conveyor" but to solve it you figure out the solution to "build an arbitrarily long conveyor" and then apply that to "build a 100km long conveyor".
It worked out in Paris for quite a while, granted it was smaller than pallet workloads but still, a large physical object transportation network (akin to pneumatic tubes) was quite useful. IIRC the downfall was flooding combined with degraded infrastructure due to lack of maintenance, but those are procedural and planning issues, not foundational issues that cannot be overcome.
Similar smaller-than-container transportation networks exist elsewhere, even temporary ones used for evacuating tunnels while they are being bored. Even coal strip-mining type of situations have extremely long length conveyor systems that work pretty well.
If you forget the nonsense AI picture for a moment, what they are doing is essentially not much more than extra-specialised rail, which when built for a specific purpose makes a lot of sense, especially when you want to factor in autonomy, or per-object routing instead of single-train based routing. It's already done in factories too.
I'm not arguing you can make something like this work. However it will cost a lot of $$$ and in the end you won't have anything better than known freight trains. Even if you convince every [geographical area the size of Japan] to install one, the scale factors still won't make this better or cheaper than a train.
But that's the thing, it has already been done, already been proven and it does work. Roads and classic freight rail are not the only thing that are used right now that do this.