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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

#41

Post by maxglute »

WhitneyLand wrote: post #38

- Wouldn’t this type of wall normally be built using heavy machinery without laborers lifting and placing heavy rocks? - A heavy machinery operator would no longer be needed, but wouldn’t you need 1 or more people to operate and manage the robot as well as verify the solution? It’s a really cool direction for construction but I wonder what the net/net cost savings would really be in the near future anyway.

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.

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

#42

Post by gerdesj »

toomuchtodo wrote: post #14
myegorov wrote: post #12

Earlier quoted context omitted.

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.

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 will regret it later!

In a garden setting, you will want to consider: gabions, drystone walling and "sleepers" (large lumps of wood - like railway sleepers).

Some quick material thoughts: Wood is prone to rotting, so ensure it is treated and well drained. Drystone walling can be prone to collapse unless it is allowed to drain properly and plants/weeds should be removed. It should be slanted at around 5 degrees from vertical to resist collapse. Gabions made of galvanized steel wire are extremely strong and resistant to pretty much anything. Devon Popples are an ideal filling for gabions and make a phenomenal structure.

I built a deck part way down in my garden. It is about 5m wide and sticks out about 1.8m. Behind it is a sleeper retaining wall which is about 1.8m high. I angled it back by about 2 degrees from vertical. I laid it on a concrete strip to spread the load and gravel base and back filled with quite a lot of scrap brick and rubbish for drainage. I used some 2m x 10mm stainless steel threaded rods embedded into the conc base to ensure horizontal stability (horizontal shear). I used 180mm, No. 10 passivated screws to keep the wall together whilst I built it and back filled.

"Where can we read more on this engineering"

It's everywhere but you will have to deal with local conditions. I am not convinced you are what you claim.

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

#43

Post by gerdesj »

toomuchtodo wrote: post #26
gerdesj wrote: post #24

Earlier quoted context omitted.

"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 would still need humans to erect the gabions though, no? Trying to understand the best optimization use case for this product and best fit final results. Please excuse my knowledge gaps! I’m am trying to fill those gaps.

What problem are you trying to fix?

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

#45

Post by toomuchtodo »

gerdesj wrote: post #43
toomuchtodo wrote: post #26

Earlier quoted context omitted.

You would still need humans to erect the gabions though, no? Trying to understand the best optimization use case for this product and best fit final results. Please excuse my knowledge gaps! I’m am trying to fill those gaps.

What problem are you trying to fix?

Reduction in human labor for building these types of structures. The world is getting old fast, but infrastructure is still required, both new and maintenance of what exists today. Also, job assistance that reduces the toll on humans in this industry. This prevents treating the human as a consumable when the automation can be human driven, increasing quality of life and potential career longevity (if desired).

Not replacing humans, to be clear, but helping them build better with less effort. Thank you for indulging me. I hope to eventually leave tech to build things that are needed that are built to last (I too am getting old fast).

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

#46

Post by beachy »

maxglute wrote: post #41
WhitneyLand wrote: post #38

- Wouldn’t this type of wall normally be built using heavy machinery without laborers lifting and placing heavy rocks? - A heavy machinery operator would no longer be needed, but wouldn’t you need 1 or more people to operate and manage the robot as well as verify the solution? It’s a really cool direction for construction but I wonder what the net/net cost savings would really be in the near future anyway.

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.

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

#47

Post by logtempo »

WhitneyLand wrote: post #38

- Wouldn’t this type of wall normally be built using heavy machinery without laborers lifting and placing heavy rocks? - A heavy machinery operator would no longer be needed, but wouldn’t you need 1 or more people to operate and manage the robot as well as verify the solution? It’s a really cool direction for construction but I wonder what the net/net cost savings would really be in the near future anyway.

I don't like wars, but being able to build a wall out of some broken concrete blocks without it being man handled is a good feature I believe.

Also being able to build during a long period of time (during the night for example) make the job less exhausting.

Also one could think of it as an assistant: put some augmented reality display, and let the machine showing to the operator where to put the rock.

Or help for building records: you keep the operator part, but you record the scans and position and weights during construction phase, so you can eventually run simulation later to know how the wall will change over time etc.

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

#48

Post by jacquesm »

toomuchtodo wrote: post #26
gerdesj wrote: post #24

Earlier quoted context omitted.

"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 would still need humans to erect the gabions though, no? Trying to understand the best optimization use case for this product and best fit final results. Please excuse my knowledge gaps! I’m am trying to fill those gaps.

You can fill gabions that have been pre-made by using a mini excavator. Or you can do it by hand but that's pretty labor intensive, unless you like wheelbarrows and buckets I would advise against it. Personal experience and all that ;)

The important thing with gabion is to realize that they still need careful planning, anchoring, leveling and possibly a foundation to ensure that they aren't going to shift over time.

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

#50

Post by mlhpdx »

ano-ther wrote: post #11
fnordpiglet wrote: post #6

Earlier quoted context omitted.

It could perhaps if it had all rocks available up front to scan and plan the entire wall with. But it retrieves one rock at a time and can only place on the top row somewhere. Given the geometries are random I wouldn’t expect it to reliably have tight fits given how it’s sampling and placing.

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.
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