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

ethz.ch

181–190 of 190 posts

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

#181

Earlier quoted context omitted.

> Imagine a several hundred kilo machine stepping on your toes with its full weight just because it mis-estimated your movements. "Specifications. Tesla Bot is planned to measure 5 ft 8 in (173 cm) tall and weigh 125 lb (57 kg)." https://en.wikipedia.org/wiki/Optimus_(robot) I'm aware that Tesla tends to be over-optimistic in its timeline regarding AI and robotics. I do not endorse the estimates without question and…

Oops, I significantly exaggerated the weight, thanks for finding that. Still, 60kg is no laughing matter. Also, isn't the fact that companies which are way further along in developing robot capabilities are not thinking about wide-scale commercialization decent evidence for it not being viable yet?

A rumor in some articles I read suggests that Boston Dynamics robots might actually use less AI compared to Tesla Bots. This is attributed to their origin in more traditional robot control systems research. Some of the impressive choreographies showcased in their videos were, at least in part, orchestrated by their engineers. This implies that these robots may not perform as effectively in unpredictable and partial information environments, such as the real world.

In contrast, the technology behind Tesla Bots is rooted in its research into AI for self-driving cars, which is designed to work well in unpredictable real-world situations.

I'm not aware of any public confirmation of this rumor though.

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

#183
post #67
post #64

Earlier quoted context omitted.

If the wall is going to move a little shotcrete ain't going to stop it.

I’d disagree with this. The general rule in mining is “six inches of shotcrete will hold up the world.”

Under compression. If you tried to stop a dry-stack wall from moving, it'd be under tension.

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

#184
post #183
post #67

Earlier quoted context omitted.

I’d disagree with this. The general rule in mining is “six inches of shotcrete will hold up the world.”

Under compression. If you tried to stop a dry-stack wall from moving, it'd be under tension.

Not to mention the shotcrete | granite rock binding will shred itself after a year or two of daily heat|cool cycling in the sun - the expansion rates of the two materials don't match.

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

#185
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…

I'm surprised the seeds would survive the heat and pressure of a shotgun cartridge blast that contained enough gun powder to embed them in a wall

it didn't embed them into the wall but in cracks and spaces where they could germinate.

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

#186

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/…

I'm from Mallorca and this technique is also alive there. We call these "marjades" for the terraces and the walls themselves are called "marges".

https://ca.wikipedia.org/wiki/Marge

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

#187

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/…

Dry stone walling is also very common in the UK. It's a complex and now expensive skill, but a properly-built (this bit is key) wall will stay put for well over a hundred years because the rocks can shift a little rather then cracking the structure as temperatures change and water drains right out of them. It's also very locally distinctive because the shape of the stones and therefore the wall layout and texture dep…

Completely unrelated, but are you the adhesive_wombat I would listen to on SoundCloud when I was younger?

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

#188
post #153

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/…

Interesting! I am living in Catalonia now, but in Barcelona. I haven't seen (or paid attention) to a wall like that. Will pay more attention and try to find some nearby. Thanks!

You won't find them in the city haha. That said, Catalonia is a very beautiful place and I encourage you to visit its rural landscapes, like Montserrat, Rupit and Viladrau (and of course, all of the Pyrenees)! Also in the coast I love Tossa de Mar and Sant Martí d'Empúries, near L'Escala.

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

#189
post #42

Earlier quoted context omitted.

Appreciate this. Where can we read more on this engineering? All citations are welcome, I am fascinated by this engineering domain.

There are Civil Engineers here (I only studied it at Uni - I ended up in IT!) When you deploy a structure like a retaining wall you want to try and ensure that the materials you use will retain their properties as long as possible and if part of it fails, it should not case the whole structure to fail. Add additional design requirements as you like eg colour and texture but always think about function first or you wi…

I'm not finding info on "Devon Popples" for use in gabions. Was that a typo? If so, curious what the ideal filling is.

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

#190

Earlier quoted context omitted.

Dry stone walling is also very common in the UK. It's a complex and now expensive skill, but a properly-built (this bit is key) wall will stay put for well over a hundred years because the rocks can shift a little rather then cracking the structure as temperatures change and water drains right out of them. It's also very locally distinctive because the shape of the stones and therefore the wall layout and texture dep…

Completely unrelated, but are you the adhesive_wombat I would listen to on SoundCloud when I was younger?

No, it's just a random adjective-noun pair used last time I restarted my aaccount!
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