A googol-to-one gear ratio [video] • Hacker News Board

Re: A googol-to-one gear ratio [video]

#51

Post by peteradio » Sat, Mar 07, 2020, 1:37 AM UTC

eyegor wrote: post #18

_underfl0w_ wrote: post #8

Part of me likes to thing something crazy would happen if you turned it from the other end. Turn one gear once and the gear at the far other end turns a googol times but melts somewhere around a trillion rotations. Almost doesn't feel too outlandish given a scope that already includes "more energy than the entire known universe has" (per the article) for a measurement.

I'd like to think there would be a way to turn it, but I'm fairly confident it isn't possible. With that much mechanical advantage, no material will stay together. I'm not sure whether the frame/axles will break first or if it would just strip the gear teeth.

In an imperfect build like this, it would simply bind with any attempt to turn it the other way.

Re: A googol-to-one gear ratio [video]

#52

Post by elihu » Sat, Mar 07, 2020, 1:39 AM UTC

bilekas wrote: post #43

This is insane. My OCD is tempered and my love for all things mechanical has been re-ignited. I am curious how this ratio is calculated though, I didn't drill into the relative ratios.. If anyone has a link I would love to see!

It's pretty simple: for each pair of gears that mesh with each other, one has ten times as many teeth as the other, which gives a ten to one reduction.

If you chain 100 such reductions, you get 10^100 to one reduction.

Re: A googol-to-one gear ratio [video]

#53

Post by peteradio » Sat, Mar 07, 2020, 1:40 AM UTC

warent wrote: post #13

_underfl0w_ wrote: post #8

Part of me likes to thing something crazy would happen if you turned it from the other end. Turn one gear once and the gear at the far other end turns a googol times but melts somewhere around a trillion rotations. Almost doesn't feel too outlandish given a scope that already includes "more energy than the entire known universe has" (per the article) for a measurement.

All this time we've been fussing about clean energy and perpetual motion machines when all we needed was this machine to apply essentially infinite leverage and generate a universe of energy at the flick of the wrist

Woops accidentally solved fermi's paradox and the mystery of what created the big bang, in one shot.

Re: A googol-to-one gear ratio [video]

#54

Post by klyrs » Sat, Mar 07, 2020, 1:47 AM UTC

owenmarshall wrote: post #35

chrisseaton wrote: post #4

Earlier quoted context omitted.

I'm sure it can spin a bit faster. Why can't it spin so fast that the final wheel visibly turns? Well the first wheels would melt from friction or be torn apart before then, and where are you going to get that much energy to turn them so fast? At some point there's the speed of light as a limit as well.

There are 10^80 electrons in the universe, Eddington thinks. Even if you managed to make a contraption that turned one electron into one rotation of the first wheel, and you fed the entire universe to your contraption... you’re coming up a few dozens order of magnitude short to make that full turn :^)

What's 80 orders of magnitude between friends?

https://en.wikipedia.org/wiki/One-electron_universe

Re: A googol-to-one gear ratio [video]

#55

Post by mechhacker » Sat, Mar 07, 2020, 2:03 AM UTC

Benjammer wrote: post #10

The original mentioned, Arthur Ganson's Machine with Concrete, is quite a bit more artistic. The end is cast in concrete. The idea is that there is a certain amount of energy lost as friction in each gear, per turn. If you calculate the gear ratios and how many turns of the earlier gears would be required to make the final gear move, even infinitesimally, the amount of energy lost becomes more than all the energy in…

It's also the elastic modulus of the gears. Every solid thing has some stiffness or measure of how much it compresses/stretches when it's loaded.

There will be finite (but extremely small) compressive/tensile forces that are absorbed in the stretch of the material that the gears and driveline are made out of.

Like stretching a rubber band to double its length takes a force you can feel but stretching it 1/100 of that (or one one millionth or lower) takes effort you don't even notice.

Re: A googol-to-one gear ratio [video]

#56

Post by amelius » Sat, Mar 07, 2020, 2:05 AM UTC

jagged-chisel wrote: post #30

noncoml wrote: post #27

Earlier quoted context omitted.

Impressive but imho he could take it one step further and instead of concrete on the other end, he could rotate the gear in the opposite way.

When all the slack has been rotated out, it would require a tremendous amount of force to rotate that last gear in reverse. After all, the system wants to amplify the gear speed from that end.

Yeah, but if you'd actually run the machine long enough it would simply destroy itself due to the force multiplier.

Re: A googol-to-one gear ratio [video]

#57

Post by kjaku » Sat, Mar 07, 2020, 2:06 AM UTC

So after rotating enough to reduce clearance between teeth, you can move last gear lets say tooth to the distance 10^65 smaller then Planck Length -- smallest known length, wchich is 1.6 x10^35 m and where all strange things like quantum foam, or micro wormholes are supposed to happen ...?

Re: A googol-to-one gear ratio [video]

#58

Post by hammock » Sat, Mar 07, 2020, 2:12 AM UTC

mechhacker wrote: post #55

Benjammer wrote: post #10

The original mentioned, Arthur Ganson's Machine with Concrete, is quite a bit more artistic. The end is cast in concrete. The idea is that there is a certain amount of energy lost as friction in each gear, per turn. If you calculate the gear ratios and how many turns of the earlier gears would be required to make the final gear move, even infinitesimally, the amount of energy lost becomes more than all the energy in…

It's also the elastic modulus of the gears. Every solid thing has some stiffness or measure of how much it compresses/stretches when it's loaded. There will be finite (but extremely small) compressive/tensile forces that are absorbed in the stretch of the material that the gears and driveline are made out of. Like stretching a rubber band to double its length takes a force you can feel but stretching it 1/100 of that…

>the elastic modulus of the gears

And in this case, the concrete!

Re: A googol-to-one gear ratio [video]

#59

Post by rtkwe » Sat, Mar 07, 2020, 2:15 AM UTC

jxcole wrote: post #44

Now if on the slow end you connected an exactly reversed series of gears you could configure it such that the final gear moves at exactly the same speed as the first gear, but the middle gear moves at 1/googol the speed. Of course this is likely to break down at some point but it would be interesting to see exactly what the maximum recoverable ratio is for gear movement and what the limiting factors are.

Can't imagine how long it'll take to get the slack out of that gear train.

Re: A googol-to-one gear ratio [video]

#60

Post by mechhacker » Sat, Mar 07, 2020, 2:16 AM UTC

hammock wrote: post #58

mechhacker wrote: post #55

Earlier quoted context omitted.

It's also the elastic modulus of the gears. Every solid thing has some stiffness or measure of how much it compresses/stretches when it's loaded. There will be finite (but extremely small) compressive/tensile forces that are absorbed in the stretch of the material that the gears and driveline are made out of. Like stretching a rubber band to double its length takes a force you can feel but stretching it 1/100 of that…

>the elastic modulus of the gears And in this case, the concrete!

Yup, bingo. Although every single thing, gears included, will have some deflection.