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A DIY M&Ms and Skittles sorting machine

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Re: A DIY M&Ms and Skittles sorting machine

#61

Post by jfim »

taneq wrote: post #56
Drdrdrq wrote: 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?

Well, kind of both. As an engineer I applaud the fact that it optimizes for maximum usage while remaining in-spec. I'd still hope they preferentially discard the really nasty stuff. A few slightly discoloured grains per kg is much better than an entire dead mouse every 100kg.

You'd be surprised how disgustingly high the legal limits are for food to be considered defective in the US, though.

http://www.fda.gov/Food/GuidanceRegulation/GuidanceDocuments...

Re: A DIY M&Ms and Skittles sorting machine

#62

Post by germinalphrase »

ThrustVectoring wrote: post #47
yesbabyyes wrote: post #31

Earlier quoted context omitted.

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…

A list of which would make for an interest design book.

Re: A DIY M&Ms and Skittles sorting machine

#63

Post by [deleted] »

ThrustVectoring wrote: post #47
yesbabyyes wrote: post #31

Earlier quoted context omitted.

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…

[deleted]

Re: A DIY M&Ms and Skittles sorting machine

#64

Post by zkms »

Animats wrote: 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…

https://www.youtube.com/watch?v=Lz88nsWL4kw there's also similar sorting machines for larger items (tomatoes in this case) that use mechanical paddles instead of air bursts to shoot down unwanted items.

Speaking of air bursts, here's an example of the sort of valve that gets used to actuate (with precise timing constraints) the air burst:

http://www.matrixairvalves.com/sorting-manifolds.php

Re: A DIY M&Ms and Skittles sorting machine

#65

Post by elihu »

I wish I had a link, but this reminds me of a machine that was at the OMSI Maker Faire in Portland last summer that measured the shininess of pennies and then directed them into a large board with columns (kind of like a giant connect-four board).

The machine sorted the pennies to match a greyscale image given as input, so that the final output is a penny mural ready to be encased in epoxy.

Re: A DIY M&Ms and Skittles sorting machine

#66

Post by a_w »

ue_ wrote: post #53
jacobolus wrote: post #43

Earlier quoted context omitted.

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.)

That doesn't sound like a very nice thing to do. I wonder if capitalism is to blame, as I would certainly blame capitalism, or good old fashioned egotistical rivalry that I'm told was common in many areas of life then between the USSR and the US. I'd say that feeding humans or even livestock is more important than profits. Or at least, it ought to be.

Unfortunately for some profit is still more important than human health or the environment [0]

"Trafigura, Vitol and BP exporting dirty diesel to Africa, says Swiss NGO

"Traders blend cheap fuel with sulphur levels many times the European limit for sale in African countries, says Public Eye"

[0] https://www.theguardian.com/world/2016/sep/15/trafigura-vito...

Re: A DIY M&Ms and Skittles sorting machine

#67

Post by [deleted] »

ThrustVectoring wrote: post #47
yesbabyyes wrote: post #31

Earlier quoted context omitted.

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…

[deleted]

Re: A DIY M&Ms and Skittles sorting machine

#68

Post by BillyParadise »

You could probably sell one of these into every concert theatre in the world. I'm wracking my brain and exercising my google-fu, but I can't seem to find/remember which famous musician wanted only one color of candy on their rider. Or was it everything except the green ones. Or something like that.

Re: A DIY M&Ms and Skittles sorting machine

#69

Post by sahinabi »

BillyParadise wrote: post #68

You could probably sell one of these into every concert theatre in the world. I'm wracking my brain and exercising my google-fu, but I can't seem to find/remember which famous musician wanted only one color of candy on their rider. Or was it everything except the green ones. Or something like that.

van halen -

apparently they don't want the green ones : http://www.snopes.com/music/artists/vanhalen.asp

Re: A DIY M&Ms and Skittles sorting machine

#70

Post by Hello71 »

yesbabyyes wrote: post #31
Hello71 wrote: 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…

that seems implausible to me, for two major reasons:

1. you're suggesting that the machine has a zero percent false positive rate, which I believe given the circumstances is physically impossible. for this type of machine, there must necessarily be some increasing function relating false positive to true positive rate. perhaps doubling true positives from (making up some numbers) 0.0001% to 0.0002% only wastes 0.01% of the available grain, but either way, I refuse to believe that increasing the true positive rate is truly "free".

2. you're effectively stating that the grain processors take out most of the bad grain, then dump it back in. given that the allowable percentages of "bad material" are (as far as I know) quite low, I don't really see why they would bother reducing the amount thrown away from, say, 0.0001% to 0.00008% to save that tiny amount of money.

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