
Watch a Hypnotizing Machine Sort River Rocks by Age - tzury
http://www.atlasobscura.com/articles/watch-a-hypnotizing-machine-sort-river-rocks-by-age?utm_source=facebook.com&utm_medium=atlas-page
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bsder
Awww, this is an art installation. That disappoints me. I was hoping that
there was a good scientific reason why somebody had to do this ...

ObRobot: ABB Robotics pickers are always good robotics porn ...

[https://youtu.be/wg8YYuLLoM0?t=77](https://youtu.be/wg8YYuLLoM0?t=77)

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kpil
It's awesome, that's what it is. It's a nice illustration. You could have a
student do it, but it would not be as fun.

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vinchuco
Request to remove "hypnotizing" from the title.

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munificent
This really begs for a time lapse.

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sp332
There's a lot more information on the actual video page.
[https://vimeo.com/167126696](https://vimeo.com/167126696)

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thomk
I'm curious about the sorting algorithm. The article states that rocks are
actually sorted twice. I wonder how so.

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slackingoff2017
My guess is the first pass places every rock into a known location and the
second one moves them to their correct spot. Assuming the machine starts out
without knowing the total number of rocks this would make sense. You can't put
any rocks into the right spot until you've seen all of them.

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BugsJustFindMe
Surely a machine that can see rocks can see all the rocks without moving them.
It might need to weigh them to measure density, but that still doesn't explain
double sorting.

