91–100 of 190 posts
I wish there were more companies in the US that can look at problem and solve it to a great deal of technical complexity. It seems like we’re too focused on large and shiny objects.
Would be best if some entity quickly moves towards commercialization/packaging of this solution.
Earlier quoted context omitted.
Not only is this a technical marvel, but it has potential construction physics implications. In simple terms, currently we expend energy to fragment rock, and then we expend additional energy (as concrete) to glue it back together. We do all this to re-arrange rocks into a shape (and strength) we want, and most importantly to do it cheap . Suddenly, an alternative just got a lot cheaper. Clearly this isn't fully bake…
The problem with dry stone construction is that you cannot determine the performance characteristics required for, say, a building foundation. Not all boulders are created equal, but a professional concrete pour, mixed and installed to the manufacturer’s specification is going to have a guaranteed maximum strength- something random boulders will not have. What we can do is create our own concrete mix using Portland c…
ETH Zurich[1, 2] is fairly famous as an engineering school. Somehow in my mind it is linked with computer scientist Edsger Dijkstra[3], but according to the Wiki he was never based there. [1] https://en.wikipedia.org/wiki/ETH_Zurich [2] https://ethz.ch/en.html [3] https://en.wikipedia.org/wiki/Edsger_W._Dijkstra
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
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?
The change in colour will be the result of a change in source of boulder. The whole point is that they are "recycling".
Earlier quoted context omitted.
The problem with dry stone construction is that you cannot determine the performance characteristics required for, say, a building foundation. Not all boulders are created equal, but a professional concrete pour, mixed and installed to the manufacturer’s specification is going to have a guaranteed maximum strength- something random boulders will not have. What we can do is create our own concrete mix using Portland c…
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…
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 months / years).
Earlier quoted context omitted.
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.
It's nowhere near autonomous, but it's several times faster than total manual control would be.