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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.'"
bullshit?
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
Other than being printed, what's the special part? What makes it different from every other transmission other that it has many gears and uses excessive/bad ratios between them that make the device worthless from a practical perspective.
its got 5 tooth pinions FFS, that'd be so rough and wouldn't last any length of time under load ... And then he discovered that if repeatedly chain those gears you get larger ratios still.
You can do the same thing with fewer worm gears and smoother operation.
This isn't even a little bit new, he's just chained a bunch of gears and is using the inside of the circle rather than the outside.
Someone show this guy a traditional automatic transmission or a newer CVD and watch his head explode. His gadget is pretty trivial, certainly nothing novel about it
Persistent Volume manager for Kubernetes - https://github.com/dwimsey/openshift-pvmanager
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.
This demonstrates that you can have any gear ratio you want, in the palm of your hand. UP TO 11 million : 1. It's essentially unlimited.
You may have dealt with some problems related to the 2GB or 2TB disk size limits in Windows and MBR. At the same time, other people had storage systems which would support up to 8 petabytes, or even exabytes. Exabyte storage volumes didn't actually exist, so one could say the large disk formats had no practical application, but the practical application was that it was NOT limited to 2 TB. You could (and we did) have 16 TB raid volumes, because the limit was so high as to be essentially unlimited.
I see this the same way - it demonstrates a design that has practically unlimited ratio.
And you get Machine with Concrete by Arthur Ganson.
In order to find practical applications, I think it's important to quantify what it you've got through measurements, mainly by breaking them. You want to know what kind of torque the later stages of that 11million+ ratio gearset can actually withstand. I'd probably try hooking a dremel on the "fast" end and some kind of lever pressing on an obstacle or a digital scale on the "slow" end. I suspect that some stages would be prone to failure much sooner than others. Different materials and more precise construction could yield a part strong enough to do a lot of useful things, mainly apply a lot of torque with smaller, higher speed motors. (Which is very useful when you want to reduce weight, like on an airplane, car or space station.)
Tried to build this with my 3d printer. Something broke, and something seized, and to my amazement, it turned out to have 1:infinity gear reduction.
don't cut it off www.mgmbill.org
I see this the same way - it demonstrates a design that has practically unlimited ratio.
Except theoretically it is quite clear you can keep adding gears, and as there is no limit to how large you can multiply numbers by, there is no theoretical limit to how much gear reduction you could do. And you could easily make something much smaller than this if just trying to create some theoretical illustration, as a couple of credit card sized reducing gears would give you something with the same theoretical reduction ratio that you could lose in a crack in the floor.
As far as demonstrating practically unlimited ratio, it doesn't do that, employing nothing to deal with any practical issues that often prevent you from having very large gear ratios (depends heavily on what setup and end use you have though). This is pretty much the exact opposite of a practical demonstration. It is like a student writing a FAT128 file system, claiming they can now deal with 3*10^38 bytes of storage, while being completely impractical at handling actual large data storage.
... but how does this fundamentally differ from a normal cycloidal reducer or this Differential Hypocycloid Gearbox ?
as fast as you can, aloud.
The tip of a wind turbine typically moves with 75m/s. The generator turns with 1500rpm. For all sizes of blades.
At 50m blades (100m diameter) that means the roter turns 7.5rpm. The gearing ratio needed is 1:200 - transporting 3MW continuous energy.
This video: Grinder Gears shows the key to the gearing ratio. The 'one rotation = skipping just one tooth' is demonstrated here, and it's also shown that the gear is not reversible. You can't reverse the process by turning the output gear and have it spin the input gear, it simply won't budge because it's not a direct gearing. The inner "yellow" gear rocks around a bit like turning a straw in a small soda pop bottle opening. That is: The smaller opening provides a restriction and the longer ends of the straw are allowed to have wider orbits.
The planetary gear mechanism of TFA was added to the grinder gears to provide a slow and smooth rocking motion. One obvious thing this grinder gear video shows that TFA's video leaves out is that you could mount the device fixed via the red or green ring, and harness the full combined counter rotational effect, but this halves the gear ratio since the arrows on the red and green gears will line up at the opposite side again before lining at the "origin" with respect to the yellow rocker gear.
It reminds me of the harmonic drive - a low backlash, high ratio compact gear.
Other comments have noted that a very high ratio would need very strong matariels to transfer significant power.
That's true, but sometimes the point isn't power, the point is to move things over very small distances precisely.
Even on a power drill, you're not going to move anything very far. So you need to hook it up to something where there's not much power and lots of turns on the input.
Screw it, I'm hooking mine up to the hamster's wheel.
What sort of devices is this invention geared towards?
Don't waste your vote! Vote for whoever you want, unless you live in a swing state it won't matter anyways
I can see an instant application for this, obviously using a lower ratio: hand winches.
Same principle as a block and tackle. For every turn of the crank, you can reduce the ratio to something like 1 in 100 and lift (theoretically) 100 times the crank load 1/100 the outer circumference of the spool. For a motor-driven winch, you could use a low voltage, low torque, high speed motor (like you'd get in a Dremel), spin that at 10,000rpm, reduce it in one of these blocks by 1/1,000 and end up with (again, theoretically) 1,000x the torque at 10rpm.
Political debates have me rolling my eyes so much I think I got optical whiplash. I should sue. - Foamy The Squirrel
> I'm not really all that well versed in electric motors but isn't the precision of an electric motor dependent on how precise the bursts of current are applied to it? I am assuming that any electric motor has a set minimal step it must take..
No, for tasks which require controlling the position or rate of rotation, the precision is NOt dependent on how precise the bursts of current are. You used the magic word there, "step". If you want to control the rotation of a motor with any precision, you use a type of motor called a stepper motor. You may be familiar with the commutator which regular hobby motors use to distribute current to different windings as the motor turns. By basically just removing the commutator, you end up with a motor that turns only 1/64th rotation with each pulse, and distributing those pulses to the different windings has yo be do
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.
Both the design and potential torque are astonishing.
Thanks /.
It's 3D printed, but gears are flat. It would seem to me that it would be far more sensible to laser-cut this.
I see someone discovered the planetary gear system.
I love it when kiddies discover what has been around even before steam.
Do not look at laser with remaining good eye.
That's the point of something like this... Assuming the gears could take the weight. You'd want to build the gears out of metal obviously because towards the end they'd need serious torque. But lets say you have a very low power situation... maybe a little wind mill or a small solar powered electric motor... then you need to do something that moves something huge but you don't really care if it takes a month. You set this up... walk away... come back in a month... boom.
I've decided to stop wasting my time responding to AC trolls/sockpuppets... so if you want a response from me... login.
with the approprite gearing, make one that will finish one revolution by the end of your life.
This is just another example of why 3D printing isn't "There" yet...
The concept is cool, but the material it's made out of isn't strong enough to make this a high torque device. That leaves precision, but 3D printing isn't nearly precise enough either... by the time this has made enough turns to make the output even do one revolution, the sketchiness of the printers output makes even the idea of labeling it 3,000,000/1 kind of a joke.
Maybe you could use the parts as cast forms to make metal parts out of? But even then, why not just mill it?
My God, when will this ever end? It's like trying to find the end of Pi, or the guy who spends his time adding "1" to the total.
Maybe because he has one gear travelling in one direction and another in the opposite direction. If you look at the demonstration video he gets a gear ratio somewhere between 600-800x. I guess puzzle making != engineering.
Everyone seems to be missing the main point. It uses 'multi-colored gears', 'is compact and multi-colored'.
How can I get this car out of second gear?
Have gnu, will travel.
if I add another harmonic stage to it will the device make me MORE fantastic-er and noteworthy than van Deventer?
My damn browser kills the on-screen keyboard regularly, then applies a click wherever your finger happens to be when it takes the keyboard away. So yeah, I can press the letter "H" in a textbox, the H will show up, then the keyboard will vanish it'll register a click on the submit button, which was under the H key.
I typed this post out as an SMS message. I'll copy-paste from the SMS to the browser, to avoid a repeat of the same problem by trying to type in the browser.
My local power company has four generators, wired together to provide power for the city. They are connected into a regional grid with hundreds of other generators, but to make it simple to understand ignore those and just think about the four generators which are right next to each other . What do you think happens if one generator is trying to push the grid positive while another is trying to push it negative? That doesn't work out to well, so all the generators have to be in sync to within a few milliseconds. They do that by spinning them all to run at exactly the same frequency (60hz).
Coincidentally, an overloaded generator will also slow down, because it's power source doesn't provide enough power to spin that fast against the electro-magnetic physical resistance while also supply the needed amperage. What that means is that a generator spinning to slow is a generator that overloaded. It indicates that more input power is required, so throttles should be wired to take feedback from the tach in order to maintain 60 hz.
I still find it odd that people completely make stuff up completely from their imagination and post it as if it were fact, without having the foggiest idea what they're talking about.
Splendid post. You might, however, want to include a potentiometer with those microphone jack leads. That way you won't be applying 120 volts to an input designed for less than 100 MILLIvolts.
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Comment removed based on user account deletion
>. There have been a couple of subjects, my Ph.D is in Applied Mathematics, where I can trace it to the source (or what appears to be the source) where somebody either did not know, made a mistake, was willfully negligent, or just failed to communicate well.
That reminds me of some .htaccess rules I posted back in the 1990s. Several other web sites immediately copied-pasted it, without link or attribution. A couple of weeks later, I found an error in my code and fixed it. I couldn't fix the dozen or so sites, some very popular, who copy-pasted me, nor the hundreds of sites who copy-pasted from the first generation of copiers. Seventeen years later, most sources which show how to prevent hot linking still include my original error - an error I corrected in 1998. Which means most web sites which attempt to prevent hotlinking are affected by that error I briefly had on my site.
So yeah, I'm the erroneous source. :)
"The final gear is fixed in a block of concrete. If it were free to turn, it would make a complete revolution in about two trillion years."
I'm guessing that because of the amount of "play" in the gears, there will be no stress building up inside that concrete any time soon... amiright?
That that is is that that that that is not is not.