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Autonomous excavator constructs a six-metre-high dry-stone wall

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Re: Autonomous excavator constructs a six-metre-high dry-stone wall

#101

Post by highstep »

mlhpdx wrote: post #50
ano-ther wrote: post #11

Earlier quoted context omitted.

It scans 20-30 (a truckload) before building a section of the wall with them.

Exactly as I do as a human when I build such walls (several of them in my life). It’s a very difficult spatial problem to fit the stones into a pretty, stable structure. No doubt something large memories and detailed spatial search on a computer could help with. That doesn’t seem to have happened in this example, though. That wall is horrendously ugly.

Not only ugly, but unstable and sketchy. I wouldn't go near that wall.

Re: Autonomous excavator constructs a six-metre-high dry-stone wall

#102

Post by TomWhitwell »

aristophenes wrote: post #96

The photo of the wall in the article is obviously digitally altered, just to the left of the person walking. The rocks change into uniform smooth grey, and it doesn’t match the reflection in the water. Is it supposed to be the digital plan of the wall vs the real thing?

Yes, I think it's an artistic interpretation of a digital model of the stones - how the autonomous system sees them.

Re: Autonomous excavator constructs a six-metre-high dry-stone wall

#103

Post by diroussel »

beambot wrote: post #99
schiffern wrote: post #87

Earlier quoted context omitted.

So the question becomes, how do existing concrete manufacturers determine whether locally sourced materials ("random rocks") are suitable? In traditional dry stone construction, strength of each rock is determined by sound and by sight. It seems crazy, but nowadays this should be feasible with a neural net. If you want to get fancy (or achieve high reliability) add ultrasound in the grippers or other sensor modalitie…

> how do existing concrete manufacturers determine whether locally sourced materials ("random rocks") are suitable? They test individual samples from each pour on a calibrated press. For large buildings and critical pours, they'll keep & test multiple samples that undergo accelerated aging to make sure they're up to spec for the anticipated lifetime of the building (or until the concrete fully stabilizes over a few m…

So could catagorization of local stone based on acoustic and visual indicators, combined with random sampling and strength testing provide the assurance needed that a wall will have the required structural properties?

Re: Autonomous excavator constructs a six-metre-high dry-stone wall

#104

Post by evilaubergine »

rkangel wrote: post #98
aristophenes wrote: post #96

The photo of the wall in the article is obviously digitally altered, just to the left of the person walking. The rocks change into uniform smooth grey, and it doesn’t match the reflection in the water. Is it supposed to be the digital plan of the wall vs the real thing?

It absolutely matches the reflection in the water - you can see the hard hat of the person and the colour transition. The change in colour will be the result of a change in source of boulder. The whole point is that they are "recycling".

where were the wireframe mesh rocks sourced from?

Re: Autonomous excavator constructs a six-metre-high dry-stone wall

#105

Post by hutzlibu »

toomuchtodo wrote: post #9
beachy wrote: post #8

This seems like game changing technology. There are a heap of such walls around here, some built long ago by Dalmation immigrants (and some allegedly by German POWs). It's quite labour intensive and highly skilled to create them. We have some on our property, used to retain the hillside after land slips. They were built with an excavator by a gnarly old guy who was unbelievably skilled. One thing I wonder is whether…

You could potentially shotcrete (spray it with concrete to reinforce) the wall after the robotic excavator is done if you’re concerned about stability. I can’t speak to whether you can highly automate this as well, but it seems possible with current state robotics with human operators. https://en.wikipedia.org/wiki/Shotcrete https://www.geostabilization.com/technology/shotcrete-robot/ https://dawinvehicles.en.made-in…

One of the ideas of this project is, to NOT use concrete, to not have CO2 emmisions.

And depending on the "skill" of the robot and its algorithms, it could be very stable. I know that quite some ancient buildings in south america are put together just with stones put together(with precision and shaping of stones). They survived earthquakes and are still standing. So if enough stones of various shapes are avaiable - you won't need concrete. The weight and friction will hold them together.

Re: Autonomous excavator constructs a six-metre-high dry-stone wall

#106

Post by tsimionescu »

nopinsight wrote: post #58

Nice achievement! With upcoming multimodal foundation models, there will be many more robots with increasing capabilities soon. The world of robotics will look very different just in the next 5 years. Some announcements: China’s plan: “…China aims to be ready to mass-produce humanoids by 2025.” https://www.therobotreport.com/china-plans-to-mass-produce-h... Tesla Robot: “…it would be low cost and available to the pub…

You should take both of those announcements with a huge dollop of salt. Even the article you shared is extremely skeptical of the actual progress of Tesla's robot. And Chinese press releases should really not be read into too much - they are often much more for internal signalling then information.

Either way, there are companies which are much farther along than those - Boston Dynamics has a series of extremely impressive robots. They are still very far away from being a consumer technology. The kinds of physical power required to achieve the movements makes them extremely dangerous to be around on any malfunction or glitch, and they are very heavy machinery. Even animals and other humans, which are far more advanced in terms of their ability to control their movements, sometimes accidentally hurt others (stepping on your toes, turning around and hitting you when they didn't know you're there, etc.). Imagine a several hundred kilo machine stepping on your toes with its full weight just because it mis-estimated your movements.

Re: Autonomous excavator constructs a six-metre-high dry-stone wall

#107

Post by RichieAHB »

rendaw wrote: post #76

I'm surprised centimeter precision is sufficient. I'd have thought millimeter precision or so would be required. It feels like 1cm could accumulate to a gap or could spell the difference between stable points contacting and not.

IIUC cm precision should be fine if the algorithms looking for stable placement accounts for that cm (and reality id imagine it’d account for less precision than that). If a placement needs sub cm precision the algorithm would just discard that option.

Additionally there shouldn’t be any accumulation in a specific direction. Any accumulated gaps would be accounted for when placing the next rock and rectified to within a cm.

Re: Autonomous excavator constructs a six-metre-high dry-stone wall

#108

Post by adammarples »

Daub wrote: post #55

Having made a few dry stone walls I can attest to the merit of this achievement. Judging where rocks are to be placed, and in what orientation is a zen art. Anecdotally... I once tried to get wild flowers to grow on a stone wall. Every year we would seed the wall, only for the seeds to fall out or be eaten by birds. On inspiration, my boss filled a few shotgun cartridges up with seeds and fired them at the wall. Perf…

It sounds like judging where rocks are to be placed is a simple optimization algorithm

Re: Autonomous excavator constructs a six-metre-high dry-stone wall

#109

Post by 7734128 »

aristophenes wrote: post #96

The photo of the wall in the article is obviously digitally altered, just to the left of the person walking. The rocks change into uniform smooth grey, and it doesn’t match the reflection in the water. Is it supposed to be the digital plan of the wall vs the real thing?

If you zoom in you can see that it's a polygon like mesh. It's certainly supposed to be how the rocks are represented in the system.

Re: Autonomous excavator constructs a six-metre-high dry-stone wall

#110

Post by jvidalv »

Just wanted to share that in my country (Spain) and more concretely in my area (rural part of Catalonia) we have a building technique called “Pedra Seca” literal translation is “Dry Stone”. It basically involves building stuff with just rocks, nothing more. It’s still in use mostly in agricultural fields.

Here are a few examples:

https://dd9de8c7b7.cbaul-cdnwnd.com/b5fbcf0e77b7b72ef95acd62...

https://static1.ara.cat/clip/98e3619e-8dd2-4c0b-828c-254a62e...

The google search:

https://www.google.com/search?client=safari&sca_esv=58408328...

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