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Extreme Reduction Gearing Device Offers an Amazing Gear Ratio
ErnieKey writes: The 3D printed extreme reduction gearing device, created by long-time puzzle maker M. Oskar van Deventer, may leave you puzzled for its obvious applications, but the coaxial cranking mechanism offers potential in a variety of real-world applications with multi-colored gears that move in opposite directions at a ratio of 11,373,076 : 1. This 3D printed reduction gearing device is compact and multi-colored, and looks deceivingly simple at first glance. Developed through a complex algorithm, it could possibly offer potential as parts for machines like 3D printers, aerospace and automotive components, as well as perhaps robotics and a variety of motors.
it could possibly offer potential as parts for machines like 3D printers, aerospace and automotive components, as well as perhaps robotics and a variety of motors.
Correct me if I'm wrong, but wouldn't that much reduction be fairly pointless? Wouldn't you basically have to make it out of unobtainium (the high-torque parts, anyway... most of it, that is) in order to do useful work with it?
"You're right," Fisheye says. "I should have set it on 'whip' or 'chop.'"
It has a very specific meaning and the way it is used in this article is not it. Sorry, pet peeve.
TFA seems to conflate the ideas of speed ratio and force multiplication. That is only true if the mechanism is perfectly efficient. In practice some of the input force will instead be consumed opposing friction in the mechanism and the output force will be limited by the stretch of the parts. So the maximum force multiplication achived may be substantially lower than the speed ratio.
To make a high ratio gearbox practical for force multiplication the low torque high speed parts need to be small to minimise friction while the low speed high torque parts need to be large to prevent them from breaking.
To make it practical for accurate rotational positioning again the low speed parts need to be large, otherwise flexibility in those low speed parts will compromise the ability to accurately maintain position.
note: i'm known as plugwash most places but i screwd up registering that here somehow in the past and now can't register
In the end, a slightly less impressive variation on "Machine with Concrete."'?
I do not deploy Linux. Ever.
This is a fun device that can show you what can be done with 3D printed plastic. That said, it's useless. It would be really cool if I could apply 1 pound of force to the crank, turn it a Million times, and have it apply a Million pounds of rotational force at the other end. But it's made of plastic, so it won't do that. Indeed, the fast-rotating parts would wear out before the slow-rotating part made a single turn. So it's not even good as a kind of clock.
All that said, it's a good conversation piece, and probably worth the price for that.
Bruce Perens.
And you get Machine with Concrete by Arthur Ganson.
The "special" part is that it's 2 planetary sets driving a third acting as a coaxial differential, *not* a long chain of reductions.
Did you bother to look at the video and see how he worked out the gear ratios? With a relatively small number of gears he managed to have a one in the denominator of the ratio equation and at the same time he made the numerator be 11,373,076. A design with those properties doesn't leap off the page the first time you try it. It's really hard.
He said it was compact for the extreme ratio. I'll bet if you tried to do something similar it would be a lot bigger, need a lot more gears, and might not even work. Care to prove me wrong? (Hint: no combination of worm gears comes even close.)
You're just another Slashdot Pundit, living in your parents basement and sneering at people who get stuff done in order to make up for the fact that you're utterly useless. Anyone with a life would never make such a stupid comment.
Why is Snark Required?
My browser submitted the post before I was done writing it.
Distributing those pulses to the different windings has to be done externally, via transistors or other controlling electronics. So the pulses don't need precision timing or anything, you just have to count them.
On the other hand, stepper motors can only have a certain number of steps per revolution (64 steps is a typical example, but other values are available) . So if you want something like 1/1000th turn, you do need a gear or screw of some sort.
For very slow rotation, such as clocks, synchronous motors are normally used. They use the ac swing from positive to negative rather than a commutator. They're quite accurate, and used to be more so, because the ac supply is regulated to exactly 60 hertz in order to allow power companies to interconnect. Again you don't have to deal with any intricate control of the pulses, just count the number of swings from positive to negative and back. The precision of the 60 hertz ac rate was recently reduced in the US, but it's still precise enough for most purposes.
... Everything I do is more creative than this. Just because you have no clue that this isn't impressive doesn't magically make it so.
I know how it works, there is nothing new about it. The video doesn't demonstrate anything new or uncommon, the only uncommon part about it is that he used shitty ratios that would break the instant it wasn't free wheeling. You can not use 5 tooth pinions if you want to do anything more that a free wheeling toy.
Hint: LOTS OF THINGS SMALLER CAN EASILY BEAT THAT RATIO GIVEN THE SAME CONSTRAINTS. Those things are just worthless in a lot of cases.
Open up a old school watch. That's impressive. Then get back to me about how compact this thing is for its ratio. Combine any two hand wound mechanical wrist watches, just the gears between hours and seconds, your already at 1:12M, and many times more "compact"
Get a clue before you make an ass out of yourself next time.
Persistent Volume manager for Kubernetes - https://github.com/dwimsey/openshift-pvmanager
Creative? Maybe. Revolutionary? No.
Dude. It's a giant gear train in motion. It is by definition revolutionary.
Nostalgia's not what it used to be.