[HN Gopher] A swarm of robots built this tunnel [video] ___________________________________________________________________ A swarm of robots built this tunnel [video] Author : cjg Score : 42 points Date : 2022-12-21 10:33 UTC (12 hours ago) (HTM) web link (www.youtube.com) (TXT) w3m dump (www.youtube.com) | Gravityloss wrote: | The content about the new method starts roughly here: | https://youtu.be/bfJY0syocfU?t=227 | interroboink wrote: | The Wadsworth constant strikes again (: | nathan_phoenix wrote: | Seems like a cool concept but also quite early stage with unsure | viability. Curious how transportation would change if they | succeed in making tunnels x2 cheaper. | euroderf wrote: | That still leaves American tunnels ridiculously more expensive | than elsewhere in the West. There are more reliable wins | elsewhere in the overall process. | geocrasher wrote: | Seems very "Popular Science" to me. I expect to see that when I | see the Moller Sky Car in production. | strangattractor wrote: | Looks much more interesting than the Boring Company. They look | large enough to fit something other than Tesla's through them. | throwawaymaths wrote: | This is 100% how the first permanent (i.e. not tin cans) lunar | habitation will be built, possibly Mars too. | bagels wrote: | What gives you such confidence in your statement? | dylan604 wrote: | using a throwaway account gives one all sorts of confidence. | melling wrote: | @6m Could build tunnels up to 10 times faster and at half the | cost. | | A lot of US cities could be retrofitted with subways. | | Even NYC metro area badly needs a few more tunnels: | | https://en.m.wikipedia.org/wiki/Gateway_Program_(Northeast_C... | hutzlibu wrote: | "Could build tunnels up to 10 times faster and at half the | cost." | | Maybe. So far they have only drilled through wood and not | stone. | sroussey wrote: | While this method can create new tunnels, I see it's first best | use at enlarging existing tunnels by setting the "concrete" type | stuff surrounding an existing tunnel but at a larger diameter | (well, also need not be round!). Then demolition of the existing | tunnel walls and some cave in of other materials and you have a | new larger tunnel after cleanup. | dylan604 wrote: | You'd still lose use of the existing tunnel. Why not build a | new second tunnel? | Animats wrote: | Now that's an interesting idea. Dig a ring of small holes around | the perimeter of the tunnel and use them to build the tunnel | liner. Then remove the dirt and rock in the middle. | | Microtunneling has been around for years. It's done with small | tunnel boring machines, to install pipes of various sizes.[1] The | drives are usually not that long, because these are pushed from | the starting point, not self-propelled like the big TBMs. | | That's what they seem to be doing here. There's some hand-waving | around the "special borepipes". Those are apparently drilled by | existing techniques. Only when all those tubes are in place | around the perimeter of the tunnel volume do the robots move in | and grout. Trying to do all that pumped concrete grouting work | with those small tubular robot vehicles is a neat trick. The | animations show them drilling small crosswise holes longer than | the tube diameter, which is a bit suspicious. | | All this would seem to be limited by how far you can drive the | "special borepipes" using standard drilling techniques. That can | be quite a distance, though; the current microtunneling record is | 2.2 km.[2] That's more than enough for most urban projects. | You're going to want stations and access points along the route, | so the drive can be done in sections. | | (When watching the original post video, start at 3:30 to skip a | long ad.) | | [1] https://www.youtube.com/watch?v=teVrJs6CSe0 | | [2] https://www.napipelines.com/building-big-microtunneling- | terr... | amelius wrote: | What is the advantage? You have to remove the dirt in the | middle either way. And with a bigger drill you can get through | tougher obstacles. | afinlayson wrote: | I figured the Boring company had a similar approach, but when I | researched their technique ... I was very disappointed. This is | really cool. Can't wait to see it go into production. | thombat wrote: | How does Boring's technique differ to conventional current | approaches? (i.e. I'm too lazy to repeat your research..) | tshadley wrote: | So the robots are building the shell of the tunnel before the | material within the tunnel (spoil) is removed. | | The robots do not seem specifically involved with removing spoil | or even carving it into smaller pieces (at least pieces smaller | than the tunnel diameter). | | Does this mean building tunnel shells is the hardest part of | tunnel building, not breaking up and removing spoil? | | Or does this approach somehow make it easier to fragment and | remove the spoil since it's now in tunnel-sized chunks? | | (Edit: Yes, stabilising the tunnel is the hard part, see | excellent and thorough answer by rmccue) | rmccue wrote: | Stabilising the tunnel is the hard part; anyone can dig a hole, | but keeping that hole stable is what makes it a tunnel. The big | innovation from Brunel and the ancestor of most modern tunnels | was the tunneling shield [1], which provided an area to safely | work ahead of the supporting structure. | | Modern Tunnel Boring Machines (TBMs) incorporate a tunneling | shield, with the addition of a large machine behind the cutting | head which builds the tunnel walls as it goes along. | | The innovation here is to build the stabilisation first and | tunnel out the rest; it seems more akin to pipe/box jacking [2] | in that sense, where you basically force the outer walls | through the material using hydraulics, then excavate the spoil. | Their demonstrations so far are at the scale where box jacking | would probably make more sense, but if they can deliver on the | promise of having effectively an arbitrary long tunnel then | that'd make the technique more broadly applicable. | | [1]: https://en.wikipedia.org/wiki/Tunnelling_shield [2]: | https://en.wikipedia.org/wiki/Pipe_ramming ___________________________________________________________________ (page generated 2022-12-21 23:00 UTC)