Random Number generator

[Zachhale]

Good morning,

I have had trouble with this lately. I was hoping for some assistance. See below:

Mechanical Random Number Generating Device:

Need:
Mechanical device that chooses a number 1-10 through a process that is/seems random to the viewer(s). Device must produce a random number anywhere from 1 through 10 which cannot be affected by any factors within the operator's control.

Range requirement:
10 possible outcomes.

Device/design can not contain or be associated with the following:
Traditional raffle drawing devices such as; Manually/Electrically rotating capsule, free standing 'pick from a hat' method, multi-sectional wheel, air induced 'lotto ball' machine etc.
Printed Circuit Board components using binary methods or algorithms to produce a random number.
Slot Machine mechanics.

 

[itsmoked]

Nuclear decay is completely random. Detect events and the times between them are random.

Keith Cress
kcress -

http://www.flaminsystems.com

 

[IRstuff]

see

https://www.imagesco.com/kits/random-number-generator.html

TTFN (ta ta for now)
I can do absolutely anything. I'm an expert!

https://www.youtube.com/watch?v=BKorP55Aqvg

faq731-376 forum1529 Entire Forum list

http://www.eng-tips.com/forumlist.cfm

 

[3DDave]

My favorite was lava lamps with photo sensors looking for the blobs to go by.

 

[itsmoked]

Blobs.. didn't see that coming.

Keith Cress
kcress -

http://www.flaminsystems.com

 

[btrueblood]

10-sided die.

 

[3DDave]

Blobs - they are so unpredictable they made a movie about just one.

 

[dik]

Can you use random mouse movement to generate the 'seed' and then proceed from there. Many programming languages have a random number generator 'built in'.

Rather than think climate change and the corona virus as science, think of it as the wrath of God. Do you feel any better?

-Dik

 

[GregLocock]

One language I used, BASIC on the Sharp MZ 80K (a PET clone) generated random numbers in the range 0 to 1 by multiplying the previous 'random' number by 3 then modulo 1

I only found out because I plotted an x y graph of consecutive random numbers, or something like that.



Cheers

Greg Locock


New here? Try reading these, they might help FAQ731-376

http://eng-tips.com/market.cfm?

 

[dik]

You might want to gander at:

https://saliu.com/bbs/messages/624.html

Random number generators for most programming languages are a little more intensive that n*3 mod 1... and have improved over the decades. I remember generation 100,000 random numbers and counting them in 'bins' of 0 to 9 and having nearly the same number in each bin... that was on a 286 way back when... the random generator started with a 'seed' and using the same seed, it would generate a second set of 100,000 numbers that were the same... to do it right, you had to start with a random seed.

Rather than think climate change and the corona virus as science, think of it as the wrath of God. Do you feel any better?

-Dik

 

[3DDave]

Typically there are two random number functions, though they sometimes have a single function call.

In one the seed is given and this is so the sequence can be exactly repeated so that the focus can be on the way the numbers are being processed without having the addition of variation due to the sequence changing. If the seed is omitted then they often use as a seed the last few digits of the millisecond timer managed by the OS at the instant that part of the function run, so it won't repeat so easily. Some languages are even better.

https://en.wikipedia.org/wiki/Random_number_generation#Computational_methods

A nice pseudo-random sequence is from linear feedback shift registers which generate numbers in a sequence that is not easily predictable over short ranges of observation.

Like playing cards - if 51 are dealt one should be able to guess the last one, but anywhere else in a well-shuffled deck deciding what the next card will be is sufficiently difficult to make card games entertaining.

 

[IRstuff]

The OP is/was looking for a MECHANICAL means of random number generation

TTFN (ta ta for now)
I can do absolutely anything. I'm an expert!

https://www.youtube.com/watch?v=BKorP55Aqvg

faq731-376 forum1529 Entire Forum list

http://www.eng-tips.com/forumlist.cfm

 

[3DDave]

It can be a mechanical feedback shift register. Just has a lot of parts. Maybe with pneumatics? Does that count as mechanical or not allowed because it's air powered (but not "induced" for whatever exact restriction there is. All humans are air powered to the extent that if the air pump stops the power goes out.)

10 playing cards shuffled is certainly an answer. Reshuffle the 10 between picks.

A rolling rod with 10 faces would work - also has the advantage since it's even that there will be a single number on top, rather than having to deal with numbered edges. Maybe that's a "rotating capsule?"

It really sounds like a class assignment - the sort where the instructor thinks it's really good to pick an area that has had upwards of 10,000 years of investigation by hundreds of millions of people and from which there have been extracted the optimum answers for any given application and says - let me torture some students to re-invent the ideas that sucked and were rejected and then we can criticize them for all the reasons they suck.

How fun is that. But then they can all enjoy the investigation of the inevitable failures of their thought processes instead of simply looking at the workable designs and why there are different solutions to what appears to be a single task.

Just found out, for example, that Jackpot machines have alert lights that are hardened against EMI - because it was found that sometimes the token/coin accepter mechanism can fail or misreport if someone discharges a 20,000 volt burst to an exposed metal part tied to the electrical system, something that nearly identical machine status lights for use in factories are not as protected against. I'm sure the Jackpot machine electrical engineer was good - but not as good as 10,000 other people looking to break his design.

 

[dik]

Mechanical by mouse?

Rather than think climate change and the corona virus as science, think of it as the wrath of God. Do you feel any better?

-Dik