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A DIY M&Ms and Skittles sorting machine

willemm.nl

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Re: A DIY M&Ms and Skittles sorting machine

#42
post #11

Here's the commercial version.[1] This machine is sorting peas by color. Peas. Individual peas. Each individual pea is examined by cameras for size, color, and looking like a pea. Rejects are kicked into the reject hopper by an air jet. There are machines like this for most fruit. Typical throughput is a ton per hour. Most fruit and berries go through such machines today. That's why the fruit at the supermarket is so…

I took a tour of a company where they build machines like this last year, it's amazing. One guy was telling about a customer who bought several machines from them, then buys rejected products from big manufacturers who have less sensitive machines, and find the good product out of those rejects and sells that again. Almost literally finding needles in haystacks, and making money from it (and reducing food waste). (not sure if the guy was supposed to talk about this, so keeping it vague on what the product was)

Re: A DIY M&Ms and Skittles sorting machine

#43
post #18

Earlier quoted context omitted.

A friend of mine works for a consulting company specializing in optics. They invented a machine for one client which sorts wheat grains. The machine does spectrography of each individual grain, looking for moulds and fungi as well as heavy metals and more. It's a big rotating drum with small chambers for each grain. After doing the spectrography it shoots each grain off into either the selected or rejected direction.…

> But it doesn't just reject every bad seed, instead it will optimize to keep within legally accepted limits. This is just... I guess the emotion you feel when reading the last paragraph defines you as either technical guy (outrage / resignation, depending on your age and experience) or managerial guy (pure delight). I am guessing there is a switch that makes it sort properly, you know, for VIP?

In the 1970s, the USA sold a large amount of wheat to the USSR in a famous deal.

The contract stipulated that the wheat would contain something like (I heard this from a friend whose friend knew something about it; in searching I can’t find a source online, so the story might be apocryphal. I also might be off on the precise percentage.)

Re: A DIY M&Ms and Skittles sorting machine

#47
post #27

Earlier quoted context omitted.

It seems far more reasonable to me that increasing the true positive rate (bad grains rejected) will also increase the false positive rate (good grains rejected), so it's not the value of the bad grains included (which is almost certainly very small) but instead the value of the good grains which would accidentally be destroyed.

According to my friend, no; it could definitely do a "better" job to select the best grain. But obviously no one is interested in rejecting grain that could be legally sold. Further, I'm guessing that there will always be some trace amounts of heavy metals, poisons and such in any grains so it's necessarily about setting a limit and optimizing the mix for the largest clean yield (in itself an interesting problem sinc…

There's a similar issue, IMO, with new home construction. There's a minimum legal quality limit for having a home be sellable, and anything past that basically doesn't get done. It's made worse by the home evaluation metrics - square footage, bathrooms/bedrooms, and location are most of what matters for getting a mortgage (and thus for bidding on and pricing a house).

Like, if you look closely at a 100 year old house, you'll find details like "the awnings over the window are just long enough to shade the window in the summer and short enough to get sun in the winter" that basically don't make it into modern homes.

Re: A DIY M&Ms and Skittles sorting machine

#49
post #11

Here's the commercial version.[1] This machine is sorting peas by color. Peas. Individual peas. Each individual pea is examined by cameras for size, color, and looking like a pea. Rejects are kicked into the reject hopper by an air jet. There are machines like this for most fruit. Typical throughput is a ton per hour. Most fruit and berries go through such machines today. That's why the fruit at the supermarket is so…

A friend of mine works for a consulting company specializing in optics. They invented a machine for one client which sorts wheat grains. The machine does spectrography of each individual grain, looking for moulds and fungi as well as heavy metals and more. It's a big rotating drum with small chambers for each grain. After doing the spectrography it shoots each grain off into either the selected or rejected direction.…

I apologize in advance for my ignorance. Why are the different kinds of wheat grains mixed in the first place?

Re: A DIY M&Ms and Skittles sorting machine

#50
This is still an awesome project, but anyone else notice the machine makes a mistake? @ 1:10, in the background, you can see a purple skittle with green ones.

(Technically it we don't see it make the mistake, but it probably had made a mistake...)

Awesome job! Any stats on its error rate?

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