Lego Axle Sorter [video] | Hacker News Reader

Lego Axle Sorter [video]

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213 pointsdgtlmoon26 comments

I highly recommend that user's full channel:

https://www.youtube.com/user/akiyuky/videos

Akiyuky is apparently a process engineer in Japan, and posts impressive lego-based contraptions.

A lot of of them are for GBC, or "Great Ball Contraption", a collaborative project to make lego modules whose sole purpose is to move standard lego balls from one point to another. You'll often see collections of these at lego conventions. For example:

https://www.youtube.com/watch?v=_cbpNV8ivME

Thanks for sharing, this last video about GBC is just mesmerising!

Related, checkout matthias wendel who does woodwork and lego contraptions

Lego domino row building machine

https://www.youtube.com/watch?v=de4xdOVVROQ

Also, for other mechanical motions I really like watching thang

https://www.youtube.com/user/thang010146/videos

That Matthias video takes me back - one of the first channels I ever subscribed to back in 2007 because of this cool wooden marble adding machine: https://www.youtube.com/watch?v=GcDshWmhF4A

The sorting mechanism reminded me of the matrix sorter in the Linotype machine [1], in my mind still one of the most impressive mechanical achievements of all time.

Background: the Linotype allows you to type text on a keyboard, which is then automatically cast into lead slugs which can be directly used for printing. Oh, and it has optional automatic justification. It does all of this with 19th century mechanics. Here is one in action [2]. The casting mold is made up of small movable letters, called matrices [3], which have a 7 bit code at the top (made up of teeth). The matrices are then transported along a special distributor bar above the sorting bins until there are no corresponding teeth to hold them, at which place they fall down into the correct bin [4]

[1] https://en.wikipedia.org/wiki/Linotype_machine

[2] https://youtu.be/HEsAXZg-S04?t=24s

[3] https://en.wikipedia.org/wiki/Linotype_machine#/media/File:L...

[4] https://en.wikipedia.org/wiki/Linotype_machine#/media/File:L...

The impressive part is the entire system is mechanically timed and synced without using any computer control. Also, that little motor is running the entire machine. Still the best toy ever made in my opinion. Been into technic sets since the 80's.

This is one of my favorite videos of his. https://www.youtube.com/watch?v=oYhAKxOlfXQ All movement and actuation is powered by a single motor. The timing is synchronized through gearing and linkages. I am in awe whenever I watch it.

This is kind of like playing a Zachtronics game without using the sync instruction (I think each one has a "wait for signal" concept), but in real life!

Nice. This is standard industrial feeder technology, done with Legos. Here's a commercial bowl feeder, which uses many of the same tricks.[1] Here's a discussion of the design principles.[2] You don't try to align the parts much; you just push or drop the misaligned ones back into the feeder for another try.

It's good that people are doing this. The US doesn't have enough production engineers, and stuff like this is how you learn that kind of job.

[1] https://www.youtube.com/watch?v=QsJzSFVAnhk [2] https://www.autodev.com/vibratory-feeder-bowl-orienting-part...

I spent many years writing motion control software for medical instruments and I am absolutely in awe of talented mechanical engineers.

Something as seemingly simple as retrieving parts from a bin of bulk pieces, singulating them so they're in a straight line and correctly spaced, making sure they are all oriented in the same direction and then passing them off to another moving sub-assembly all the while achieving a spec of "no more than one jam every 5,000 pieces" and still maintaining sufficient throughput is amazingly difficult. Especially doing it while avoiding all the other patented solutions.

The subtleties of, say, fixing a problem by making a tab just 0.05" shorter need a level of skill that's only obtained through decades of honing your craft.

A nice discussion of doing something similar with zipper pulls:https://www.bunniestudios.com/blog/?p=4364

I want a machine that could do this will all types of Lego. I've got a 25 lb box of Lego pieces in the garage I'd love to get sorted into little plastic bags.

Harder by orders of magnitude: https://jacquesmattheij.com/sorting-two-metric-tons-of-lego/

Wow! 38,000 shapes in 100+ colors (according to that post). Yeah, that's definitely a much bigger challenge. "The final result classifies a part in approximately 30 ms on a GTX1080ti Nvidia GPU." Very nice.

I've seen way too many "How It's Made" episodes... He needs some sort of vibrating table, and a high speed belt with a "jump" of some sort to combine with those air cannons.

Why I've been meaning to build a "Lego Refractory" instead: a leaf blower at the bottom of a 10ft tall acrylic tube, with exit doors at various heights. It would sort Legos by their terminal velocity in free-fall.

Do it!!!

And film every single test run and failure. I would subscribe to this Patreon!!!

I've tried just that but could not get it to work. If you manage to get it to work reliably this is likely the fastest mechanism you could make.

Some problems that you will run in to:

- the timing will need to be very precise

- you will likely need sensors before the stations

- Lego bricks come in all shapes and sizes and will respond unpredictably to air currents

- you will need a way to arrest momentum or they'll shoot right back out

Still, this is orders of magnitude faster than my contraption if you can get it work.

Amazing. Is there a mechanical "program" (similar to a player piano roll) that sequences all of the actions? I didn't see one.

I think there's no "program" here. All the machinery does the same action for every piece, the singulation is with overflow/skipping buckets, and the sorting happens because the openings are constructed progressively bigger such that the longest axle falls of (tips over the edge due to imbalance) in the first bin, the second longest in the second bin, etc.

Still, super impressive and cool!

There are drive shafts at the bottom of the device that drive mechanical linkages.

There is one obviously visible cam (yellow half-circle) that seems to control the little wheel that shoots a single piece into slots that move over the sorting bins.

This gives me very strong ASMR.

Its never too late to have a happy childhood.

Add 2013?

Isn't there a simpler way to do this by lining up the mixed axles parallel to each other and then lifting the longest ones with a perpendicular bar?

I recall seeing this mechanism in WWII archive footage. A factory worker came up with it and he was praised for improving efficiency.

Maybe less complex in terms of moving parts, but also sounds less space efficient.

this is so ironic, I was googling around this morning trying to find out how lego organizes and classifies different blocks. This was the first video that came up

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