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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

#51

Post by Probiotic6081 »

myegorov wrote: post #12
toomuchtodo wrote: post #9

Earlier quoted context omitted.

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…

The ability of a dry stack retaining wall to shift and breathe is a feature, not a bug. For stone walls that require added reinforcement against lateral loads, look into tiebacks or geogrid reinforcement.

Or make the walls squiggly ~~~ for extra structural integrity

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

#52

Post by s1artibartfast »

zyxin wrote: post #39
Animats wrote: post #31

Nice. Heavy equipment with many degrees of freedom is hard for humans to control. Some operators are really good, but not all of them. A backhoe hooked up to a virtual reality input arm with force feedback was built several decades ago. The operator could feel obstructions, and dig out the dirt around a pipe by feel. Never became a product, though. Probably too early.

Do operators currently need to manually control every movement of the arm? I always assumed that such heavy equipment uses inverse kinematics to help the operator.

It is usually one lever per hydraulic cylinder.

The human brain already automates the kinematics.

There isn't much upside to automation and a lot of downside because of the diverse instructions required.

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

#53

Post by h2odragon »

Animats wrote: post #31

Nice. Heavy equipment with many degrees of freedom is hard for humans to control. Some operators are really good, but not all of them. A backhoe hooked up to a virtual reality input arm with force feedback was built several decades ago. The operator could feel obstructions, and dig out the dirt around a pipe by feel. Never became a product, though. Probably too early.

The force feedback would be yet another layer of tetchy stuff to keep running in a really harsh environment.

I've know backhoe operators who strongly preferred older equipment, when its too new the pins are too tight and they have no "slop" to work with. That slop is what they're using for sensory input, if you watch them. With attention and experience that's real time feedback.

The whole machine is the force feedback mechanism. You're not just sitting there in a comfy chair pulling levers, you're on top of a collection of systems all singing their own song in response to the varying loads placed on them.

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

#54

Post by throw0101b »

gerdesj wrote: post #24
toomuchtodo wrote: post #9

Earlier quoted context omitted.

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…

"You could potentially shotcrete" You could stop water draining through the retaining wall and turn it into a dam, which will not end well. My back garden/yard has a 40m drop to a lawn. The levels are managed by dry stone walls. Soil here is heavy clay with really heavy clay sub soil, so efficient drainage is imperative. As well as drystone walls, consider gabions which can form phenomenally tough retaining walls. Yo…

> You could stop water draining through the retaining wall and turn it into a dam, which will not end well.

Which is why gravel backfill with a perforated pipe at the base (that drains to day light) is specified by many/most building codes.

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

#55

Post by Daub »

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. Perfect result! The following year it was covered in flowers.

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

#56

Post by saalweachter »

gerdesj wrote: post #42
toomuchtodo wrote: post #14

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…

Another quick tip: resist the urge to stack your stones long-ways parallel to the course of wall. Instead, put the longest dimension perpendicular to the wall.

This makes it much harder for the wall to fall outward as it shifts.

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

#57

Post by rpmisms »

gerdesj wrote: post #42
toomuchtodo wrote: post #14

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 am not convinced you are what you claim.

Knowing where to look without colleagues or steeping in the field is difficult. When teaching people to code, I often run into the same issue: assuming people are good at googling, or know what Stack Overflow is.

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

#58

Post by nopinsight »

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 public sometime between 2025 and 2027. ” https://builtin.com/robotics/tesla-robot

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

#59

Post by maxglute »

beachy wrote: post #46
maxglute wrote: post #41

Earlier quoted context omitted.

There's probably a lot of savings to be had by lifting safety rules. Cram more machines to do more work on site and finish faster.

I think this is great tech, but maybe not for those reasons. On any safe site, people are already very cautious and working well back from the excavator. Some teams have a protocol where you have to make eye contact with the digger driver before you can go anywhere within the sweep of its arm.

But without the excavator operator, can you not cram more autonomous excavators to get more work done? Seems like sufficiently good sensors would allow them to work in each others safety zones for parallel work.

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

#60

Post by kbenson »

daxfohl wrote: post #40
mauvehaus wrote: post #21

Earlier quoted context omitted.

Visiting Scotland, I was told that the apparent lack of stability is what keeps the sheep from pushing against the dry stone walls there. Apocryphal or true? No idea. It's intriguing to think that sheep have a sense for stable construction, and that people have learned to deceive it.

They had no problem escaping through them in Clarkson's Farm.

I really enjoyed that show, but I have no confidence that production assistants weren't gallavanting about at night acting as gremlins.

Clarkson is first and foremost an entertainer, and I'm sure he'd agree with that assessment.

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