How to make a marble size sorting machine


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I would like to couple it with a large hopper and a mechanism that does different things based on the accumulation of certain sizes of marbles in each bay. It could play notes, and/or unleash some other thing or process. So, you load up the hopper with a random assortment of marbles, but you don’t know precisely what the result is going to be! I love marble machines, but this could add an element of randomness to how one behaves.


Have you lost your marbles?


Rats. And here I thought Matthias Wandel had made a new video for his marble machine. (

Neat idea, though.


twitch twitch uhhhhh, no. stifled scream


No, no, no. There is nothing probabilistic about this machine. If you input marbles with a normally-distributed diameter, then yes, you’ll see a rough gaussian curve in the output. But that’s because it was in the input. If the marbles are uniformly distributed, you’ll see a nice rectangle instead of a bell curve. If they’re all the same size, they’ll all go in the same box. That’s an impulse function, but only if you force an infinite number of marbles into an infinitely small box.


It would only be a normal distribution if the marbles were manufactured with a process that allowed a normal distribution of sizes to be created. What if there were only two marble machines at the factory, highly precise, and one makes marbles 1/100th of a mm smaller diameter with an error of +/- 1/10000th mm? Then, the marbles would fall into two bins, unless you had a marble sorting machine that could detect <1/10000th difference. So, that was my long, engineering way of saying I agree with your statement.


Marble size sorting machine? Psh, it’s clearly a marble colour sorting machine.


Exactly, I was imaging something with a Raspberry Pi or Arduino attached to a camera that was doing color analysis before I noticed the size differences.


How to make a marble size sorting machine

For those on the go, instead consider the benefit of making a marble-size sorting machine.


Sounds like somebody is ready for their Six Sigma course…


I just threw up in my mouth and on my desk a little. Bleh.

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