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Netbook-Run Dice Robot Can Rack Up 1.3 Million Rolls a Day
stevel writes "The owner of games site GamesByEmail.com created Dice-O-Matic, 'a machine that can belch a continuous river of dice down a spiraling ramp, then elevate, photograph, process and upload almost a million and a half rolls to the server a day. ... The Dice-O-Matic is 7 feet tall, 18 inches wide and 18 inches deep. It has an aluminum frame covered with Plexiglas panels. A 6x4 inch square Plexiglas tube runs vertically up the middle almost the entire height. Inside this tube a bucket elevator carries dice from a hopper at the bottom, past a camera, and tosses them onto a ramp at the top. The ramp spirals down between the tube and the outer walls. The camera and synchronizing disk are near the top, the computer, relay board, elevator motor and power supplies are at the bottom.' While not called out in the article, the pictures clearly show a Dell Mini 9 running the show (and performing the optical recognition of the dice values.) No, it's not running Linux."
While not called out in the article, the pictures clearly show a Dell Mini 9 running the show (and performing the optical recognition of the dice values.)
Yes but there's not a lot of "optical recognition" going on. From the article:
The dice are "Michigan Red Eyes", which have different colored pips for each value. The different colors make it pretty easy to count rolls. For example, if 6 yellow dots are found in the image, there were three 2s rolled, no need to worry about determining the proper grouping or orientation of pips.
If you control the background as being black or shades of grey (which is what it appears on that dirty dirty Windows XP screen) then your task is a lot easier and less error prone. Well done on the designer's part but surely reduces the computational work load.
My work here is dung.
"To generate the dice rolls, I have used Math.random, Random.org and other sources, but have always received numerous complaints that the dice are not random enough." Math.random is an LCG and so therefore of dubious quality. Random.org, though, is a true RNG (not a PRNG). If random.org is not random enough, either they're doing something quite horribly wrong or (far more likely) players don't actually understand what random means.
The developer says that his users have complained that his software RNGs were not random enough. His aim in building this is to build a machine that is as random as if users were throwing their own dice. At the end, he promises (light-heartedly, I presume) to punish the dice if a user shows that they are not random.
Consciousness is an illusion caused by an excess of self consciousness.
Now finally, we have the technology to experimentally verify the claims made by a certain dice manufacturer!
http://en.wikipedia.org/wiki/Hardware_random_number_generator
The AACS key is NOT 0xF606EEFD628B1CA427BEA93A9CA9773F
Please don't use this method. You are not creating an evenly distributed d8. From all 36 possible outcomes of 2d6, your "mod" d8 comes out like this: 1 - 5 times; 2 thru 6 - 4 times each; 7 - 5 times; 8 - 6 times. You COULD use some kind of conversion table, but even then you would need to throw away 4 of the 36 combinations to make it work.
It depends on the dice being not biased, and the mechanics not exerting any influence.
One should test it by letting the machine rip for a couple of days, and then analyse the produced numbers for randomness, e.g. with the diehard test suite.
Never ascribe to malice that which is adequately explained by incompetence.
It has 200 dice. Clearly it's made for Shadowrun. :)
[John]
Shit better not happen!
Shannon entropy isn't the same thing as randomness. It's a measure of balance of the distribution. You could have a high entropy generator that is very unrandom, say, one that basically alternates between outputs. Or you could have a truly random distribution that favors some outputs over others, but completely unpredictably.
Wow. Fishing for nerds is so damned easy, they take the bait even when you put a sign on it saying "WARNING: CONTAINS FISHHOOKS".
For a good nerd time, try working out the probability distribution table for Mod8(D6+D6)+1. I suggested it as a joke, but it's less horrible thank you might think.
Why not use traditional white dice with black dots on a white background. Then it is as simple as
Calculating the full image is far more work than necessary. This also easily allows for an arbitrary number of dice to be used, assuming the don't start piling on top of each other.
Because if you count 36 dots, was that six dice with six rolled on each, or twelve threes, or ...
Even if you can count exactly how many dice you rolled, was the total of six dots from four dice three ones and a three, or was it one plus two plus two plus one?
I'm guessing that knowing the exact number of dice rolled and what each die rolled is important.