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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

#31
post #27
post #18

Earlier quoted context omitted.

> 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?

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 since the regulations are not for each grain but instead for all of the grain taken together).

Re: A DIY M&Ms and Skittles sorting machine

#32
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?

Speaking of legally accepted limits, a college friend told me of his first engineering job as a chemical engineer where the factory refined sugar and graded it based on impurities sold at different prices. Sometimes a batch turned out too good so his manager would insist on pouring an amount of sand into the mix to make sure it would meet the agreed upon impurity target.

Re: A DIY M&Ms and Skittles sorting machine

#33
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?

The legal limits probably don't specify rejection criteria on a per-grain basis - they probably say something like "No more than x.x% trace of fungus Y in a given batch", so being able to calibrate on the fly is pretty important.

Re: A DIY M&Ms and Skittles sorting machine

#35
Now that green skittles have changed from "lime" to "apple" (my lawsuit regarding calling the flavor assortment "original" will be filed any day now), I need a machine like this to sort the green ones into the trash where they belong.

Re: A DIY M&Ms and Skittles sorting machine

#36
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…

The fact that the air jet can target individual bad peas out of that torrent is incredible. Computationally, probably not that difficult, but the timing required must be ridiculous.

Re: A DIY M&Ms and Skittles sorting machine

#38
post #35

Now that green skittles have changed from "lime" to "apple" (my lawsuit regarding calling the flavor assortment "original" will be filed any day now), I need a machine like this to sort the green ones into the trash where they belong.

I would counter sue the shit outta you.
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