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Cups and Balls, hand cranked.
August 3, 2012 10:55 PM   Subscribe

Cups and Balls, via crank (slyt)
posted by Marky (47 comments total) 19 users marked this as a favorite

 
I'm partly impressed by the ability of it to have the balls "show up" under different cups, but I'm probably more impressed at the quality of the wood mechanism.
posted by chimaera at 11:23 PM on August 3, 2012 [2 favorites]


HOLLY FUCK, How did they do that?
posted by growabrain at 11:29 PM on August 3, 2012


This confirms my suspicions that Criss Angel is merely a fleshy amalgamation of gears and levers and fulcrums and other engineering terms I don't comprehend, all wrapped up in an unconvincing naugahyde-skinsuit, Axe Body Spray, and a robust veneer of smugness.
You yank his crank and he levitates.
posted by Alonzo T. Calm at 11:32 PM on August 3, 2012 [2 favorites]


I'm going to wager that there is actually a ball under each cup but the cranking mechanism only releases tension on one arm at a time.
posted by Rarebit Fiend at 11:34 PM on August 3, 2012 [13 favorites]


I'm gonna guess: magnets?
posted by Mizu at 11:53 PM on August 3, 2012 [2 favorites]


∩∩∩•
∩∩•∩
∩∩∩
•∩∩∩

!!!
posted by twoleftfeet at 12:14 AM on August 4, 2012


Magnets? How do they work?
posted by Mezentian at 12:22 AM on August 4, 2012 [1 favorite]


First I thought magnets, but the balls move very slightly. Magnets would also be harder to get right - you can't afford for one of them to roll off, so you'd need three magnets for each cup - the top magnet to hold it in place, the bottom magnet in the table and the ball itself. They'd need to be very finely tuned to switch the ball up and down reliably.

If you look at stills when the cup is raised at, for example, 48 seconds, the balls do not appear to be perfectly round and I can convince myself that there is a very slight black thread glued to the top of each ball. It'd be much easier to do the trick with black thread and balls rather than magnets.
posted by YAMWAK at 2:07 AM on August 4, 2012 [1 favorite]


Magician here. Lovely trick!

Can't tell you specifics, but I can talk a little about magnets.

I can tell you for sure that

1. magnets are definitely used in magic, but
2. whenever you see anything move or change (like this) it almost certainly isn't magnets.

The trouble with magnets is that their force is inverse squared and this makes their force impossible to handle in a controlled fashion. Every experimenting magician gets magnets and tries to make things move but the issue is that as you move them closer together, there's a very wide area where nothing happens, a tiny band where you can "twitch" the other magnet - but closer than that they fly together in an instant.

As a result, the use for magnets is, well, quite different. I do have several tricks involving magnets but you wouldn't ever think of that (well, except for one which I use more as a science demonstration...)

For example, check out these tricks, the Haunted Deck and Drift. I own both of these - I have the Haunted Deck "sort of down" which means that I've practiced it a few dozen times and shown it to my wife who was mystified, but I probably need to practice it about 50 more times and show it to half a dozen people before it's "perfect". (For most tricks, if you haven't done them 100 times, there's a pretty good chance you'll fail in practice.) I bought the second one right before I left for Europe and foolishly left the instructions in the USA, so your idea is as good as mine.

Look at either of these - the key part is the smoothness of the movement. You could never do that with a magnet.

As for the trick in question, I believe it's a lovely little mechanism - and no magnets. It isn't even obvious that the demo is "hiding" anything, and I believe that if you happened to be sitting right there you'd see exactly the same thing as the camera does.

It popped up on the magic forums a couple of days ago but checking, it doesn't seem as if anyone has claimed credit for it, which is interesting. I also wasn't able to track the video down to its source - it's watermarked LiveLeak but the original there is from someone who posts hundreds of videos and almost certainly didn't make the unit, which was previously unknown to me.

The video is free of much identifying material - aside from the machine, all you see is a hand and an out-of-focus door in the background. However, based on the color of the hand, the door, and most important, the form and stylistic design of the mechanism, I'd guess that this was made in Eastern Europe, perhaps Hungary or the regions that used to be Czechoslovakia. Perhaps the creator wanted to keep a low profile so he or she could directly contact collectors and offer them something unique - that'd be a good strategy to keep their initial prices high.

My assumption is that there's more material here that hasn't been revealed yet - you wouldn't make that as your first automaton or even your tenth - and I'm looking forward to seeing more.
posted by lupus_yonderboy at 4:02 AM on August 4, 2012 [49 favorites]


I agree with YAMWAK. I definitely see threads in a few frames. Still a very impressive mechanism!
posted by orme at 5:19 AM on August 4, 2012


At around the 40 second mark you can see the revealed balls against the white wall, and threads aren't visible. The only time I see what might be threads, it's what looks more like compression artifacts between the cup and the ball against the grain of the wood.

I'm guessing there's a weak magnet in each cup to keep the ball up there. Then, in the part of the mechanism we can't see, there's a stronger magnet that swings from one position to the next that keeps the ball in place for the short time the cups are up. Any wiggle you see is probably going to be from the whole thing jiggling from the cranking and rotating and flayvin.
posted by Evilspork at 6:04 AM on August 4, 2012 [4 favorites]


Here is the original version.
posted by Algebra at 8:46 AM on August 4, 2012 [7 favorites]


(Also in HD, you can directly observe the mechanism keeping the 3 distinct balls in their respective cups at regular intervals.)
posted by Algebra at 8:47 AM on August 4, 2012


Something I notice is that the cups seem pretty big. Bigger than they would be if you were to build this to scale to look like a traditional cups and balls set. Is is possible there's just a mechanical thing inside each cup that can just pick up the ball? No magnets or thread, just some sort of grabber, or a flap that just picks up the balls? (I say this not knowing anything about building little machines like this). That loud clapping sound whenever the cups hit the table, I'm guessing, may be there to conceal the sound of whatever mechanism is hiding the balls (whether magnets, mechanical grabber, whatever...)
posted by ManInSuit at 8:51 AM on August 4, 2012 [1 favorite]


Evilspork: your "bigger magnet" theory cannot be true. Where, exactly, could it be located?

Algebra:

> (Also in HD, you can directly observe the mechanism keeping the 3 distinct balls in their respective cups at regular intervals.)

Oh, which frame and where?!
posted by lupus_yonderboy at 9:11 AM on August 4, 2012


I can't believe they didn't go with an alliance-approved robot.
posted by special-k at 9:41 AM on August 4, 2012 [3 favorites]


Looks like it's by Per Heldorff.
posted by hydrophonic at 10:04 AM on August 4, 2012 [3 favorites]


When the cups come down, you hear a "clap - clap", instead of a "clap" or even a "clapclapclap". Don't know if that matters.

You could do this with shelves I believe. The sliding back and forth puts all the balls back on their shelves. What looks like random extra movement caused from being a woodcraft object could actually be design to knock a ball off a shelf.
posted by BurnChao at 10:36 AM on August 4, 2012


I been thinking about this since I posted it yesterday. Is it a violation of the "rules" if he used electromagnets in the hands?
posted by Marky at 10:52 AM on August 4, 2012 [1 favorite]


The whole thing is a stop-motion video.
posted by empath at 11:03 AM on August 4, 2012 [4 favorites]


Magnets, strings, or--my theory--magnets on strings, which hold the balls, but pull up and drops one ball randomly. The fact that the balls don't move at all makes me think they're on a string or softer material on the bottom, filled with lead beads or something.

Makes me want to go back and watch it using pause to look for anything. Very cool though.
posted by whatgorilla at 11:18 AM on August 4, 2012


Oh, which frame and where?!

Look at :36 or :39 on the original version Algebra linked. As the camera is low, you can vaguely see a wood mechanism/shelf/whatever within each cup.
posted by pokermonk at 11:42 AM on August 4, 2012 [1 favorite]


Evilspork: your "bigger magnet" theory cannot be true. Where, exactly, could it be located?

It's on an arm under the main platform, and it lines up with one upper arm at a time.
posted by Evilspork at 3:40 PM on August 4, 2012


Er, it would be under the main platform, in my theory.
posted by Evilspork at 3:41 PM on August 4, 2012


How cool! Thank you for posting it.
posted by LobsterMitten at 4:27 PM on August 4, 2012


Strings are clearly visible in HD on all three cups. If you watch for a minute, the shape of the tops of the vertical cog-dowel things are all different. Or, I assume, one of three shapes. So then notice that the horizontal wheel they're attached to stops and jerks forward as if being released from the tension of something like a string.

I think the cogs, depending ont heir shape, catch two of the three strings so that they're under tension while the cups are up. I can't see strings down there, but it's dark and I don't see any clear function for the different cog shapes.

What's up with the cogs that're out of line with the others, though?
posted by cmoj at 5:05 PM on August 4, 2012


> It's on an arm under the main platform, and it lines up with one upper arm at a time.

That ain't how magnets work. That's just too far away to have any effect unless you had a really monster magnet, and if it did it would affect all of the balls almost equally.

Very interesting that this is Swedish, I guess my Central Europe guess was off by a few thousand kilometers.
posted by lupus_yonderboy at 4:40 AM on August 5, 2012


Well, after some more thought I confess I did come up with a workable alternative mechanism to this trick that would use magnets. :-D

I don't actually believe that's what they're using, and it isn't one of the explanations presented here, but you could do it with magnets and a little trickery... (and no electricity or junk like that).

Thing to remember is that magnets aren't some gentle, gradual thing. In practice in tricks, either the magnet is not affecting the magnetic object, or it's locked to the magnetic object. You can't counteract or improve one magnet with another. You're better to think of it as a glue...
posted by lupus_yonderboy at 6:34 AM on August 5, 2012


their force is inverse squared

Actually, because magnets only come in dipoles (there are no magnetic charges), their force is inverse quadrupled when the separation is large. So the effect of being strong at close distances and incredibly weak at longer distances is even more profound than an inverse square force, such as gravity or static electricity.
posted by jpdoane at 11:06 AM on August 5, 2012 [1 favorite]


... also why despite my love for the show, I thought last week's Breaking Bad plot line was ridiculous.
posted by jpdoane at 11:18 AM on August 5, 2012


Another video, with a bit of a glitch.

And Evilspork's idea definitely could work. There's nothing saying the main platform is actually as thick as the silver strip around it, or there could just be holes drilled into it it for small magnets to reach up near the surface. And it wouldn't be too hard to tune magnet powers and distances such that the magnet in the hand is easily and reliably overpowered by the magnet underneath the platform.

The cogs on the left are clearly selecting which ball stays down by pressing on small levers. It seems more likely to me that those are moving magnets underneath the platform (which would also explain the balls' lack of movement on the surface while the whole contraption is bonking around) rather than pulling strings to control a mechanism (magnetic or not) within the hands/cups themselves.
posted by whatnotever at 12:12 PM on August 5, 2012 [4 favorites]


My guess: large magnets (maybe 1/4" x 1" hotdogs) under the table, tiny magnets (1/8" x 1/8" cylinders) in the cups above the balls. Pawls lift and drop the big magnets under the table at least an inch. A raised large magnet under the table will suck the ball down to the table against the little magnet. A lowered large magnet is not strong enough to counter the small magnet in the top of the cup, which will hold the ball in the cup.
posted by seanmpuckett at 2:47 PM on August 5, 2012 [1 favorite]


Ooh, this new video is cool. It shows more details in the sounds the mechanism makes that some people who are smarter than me can try to decipher. He spins the crank much more slowly.
posted by Night_owl at 8:26 PM on August 5, 2012


their force is inverse squared

Actually, because magnets only come in dipoles (there are no magnetic charges), their force is inverse quadrupled

Physics pendatry: magnetic force goes inverse cubed, 1/r^3 (unless you're close to one pole of a magnet).
posted by gimletbiggles at 7:28 AM on August 6, 2012 [1 favorite]


It could be done with magnets if inside the cup/hand is a little mechanism to flip the magnet upside down. The other side of the flipped magnet is non-magnetic, and the flipping of the magnet is enough to dislodge the ball and drop it onto the table.
posted by thewumpusisdead at 5:27 PM on August 6, 2012


It certainly sounds like a bunch of balls rattling around when the cups are down.
posted by grog at 8:20 PM on August 6, 2012


It's almost certain that there aren't magnets under the little table... it'd be too hard to get it exactly right because of that inverse cube, but more than that, you'd simply see the ball get caught and "stick" in that characteristic magnet way.

I'm going to reveal my magnet solution, mainly because I'm even surer now that it isn't the real one. Simply have three bike cables going up the arms, each ending in a cylindrical magnet that sticks a tiny bit down into the cup. As you turn the crank, one magnet at a time gets pulled back by its bike cable into the arm, forcing its ball to drop onto the table.
posted by lupus_yonderboy at 4:14 AM on August 7, 2012 [1 favorite]


The whole thing is a stop-motion video.

This is exactly what I thought. The whole feeling of the video and the strange way it jerkily pans in straight lines makes it seem pretty obvious to me.
posted by EndsOfInvention at 7:26 AM on August 7, 2012


Thinking out aloud here. It seems the placement of the ball is triggered by the horizontal tooth wheel, the teeths are too odd evenly placed to be a coincidence. The teeth seems to click the trigger and that determines which one to dislodges the ball somehow. Also on the left side, for every trigger there is a wooden container that goes up and down.. any significance?
posted by radsqd at 8:57 PM on August 7, 2012


I'd say there's a ball under each cup, the balls are very light, and there's a suction tube running to each cup (inside each arm). At any given step in the sequence 2 of the tubes have suction holding those balls in the cups, and one tube does not.
posted by w0mbat at 5:14 PM on August 8, 2012


Magnets inside the cups;

when hands are down, magnets are down
when hands stop, lifting mechanism starts (visible behind manekin)
-magnets lift halfway (enough to hide balls inside cups).
-One magnet continues to lift into recess at top of cup, detaching ball (
-hands lift
Hands drop
Magnets drop

Magnets go somewhat against the mechanical design of the machine but I cannot see anything inside the cups so mechanism is probably above the balls: so no rotating pick up screw to lift from below and a pinch/grab on the side of the balls would require too much precision (and would probably be visible).
posted by BadMiker at 6:16 AM on August 10, 2012


Thirding stop animation. There may be an actual machine that works this way (as per the other video) but the first video doesn't look like a real time shoot. The way the background moves and the way the depth of field seems to fluctuate as the camera starts jerkily panning around 30 seconds is consistent with a stop-motion shoot.
posted by anazgnos at 11:45 AM on August 10, 2012


There are probably a few possibilities, though I suspect magnets since that would be the simplest solution (something like what lupus_yonderboy describes) . On 1080p, I definitely didn't see any threads. The balls are a little misshapen, but that is presumably to keep them from rolling away. The fact that they are exposed for such a short period of time on a surface designed for it all are important to keep the balls from rolling. Threads or not, that would spoil the trick quickly. Other than magnets, I could imagine some kind of grabbing mechanism, though that would have to be a bit overly complex to function within those cups; I would expect such a contraption to be prone to jamming and hard to repair.
posted by Edgewise at 3:03 PM on August 11, 2012


My immediate reaction was to assume that each cup has a ball (or more than one ball) inside, and that there is also some mechanism in each to drop/scoop up the ball, and this mechanism shifts with the turning of the hand crank.

As noted, if you stop the video (the second one, the one Algebra posted, with more detail) as the cups are lifted, you definitely see that inside the cups, the bottoms have half-circles cut into them, rather than the cups being completely open cylinders.

Annoyingly, though, as I look at a stopped frame, the half-circles at the bottoms of the cup are all in the same position, or at least very close to the same position.

That makes it a little tougher to figure out the trick--obviously, the cup that lifts to reveal the ball should be positioned differently from the two others, for any of our conjectures about the working of the mechanism to make sense. I think that they are, when the ball is dropped, but the maker of the machine has accounted for spectators trying to figure out the trickery involved, so built in a way for the cups to revert back to their default positions once they are lifted. Whatever happens, happens when the comes are down on the table, sliding around. I thought perhaps the motion of the automaton's head down as it "looks" at the cups was significant, but it "looks" at the middle cup every time.

I definitely do not, even in HD, see any threads on the balls.

Stop-motion is a distinct possibility, I agree.

There's also an interesting (to me, at least) facet to the overall design of this contraption. Note that on the right side of the machine, there is what looks like a holding chute, and on the back a kind of ladder (the top of this ladder looks like an arched doorway, if it is confusing which part I am referring to). Connected to the ladder is a horizontal beam of wood surrounded by two "walls", making a chute fit for a ball to go through. The ladder "rises" and the walls of that chute move from side to side as the handle turns, and there is a gate that lifts up behind the little automaton guy as the crank is turned.

So you have this simulation of a ball coming into that holding chute, being fed into the ladder, coming down that horizontal pathway to reach the gate, the gate opening up, a ball rolling onto the table, and the Old Shell Game of cups and balls starting. That seems really intricate for mechanisms which in reality perform no function whatsoever.

Clearly, no balls are actually coming through that gate--even if we couldn't see that with our own eyes, there is dust on the machine right in front of that little gate to prove it--but the maker sure went to a lot of trouble to make it look like that's how it worked!
posted by misha at 1:28 PM on August 14, 2012


Thirding stop animation. There may be an actual machine that works this way (as per the other video) but the first video doesn't look like a real time shoot. The way the background moves and the way the depth of field seems to fluctuate as the camera starts jerkily panning around 30 seconds is consistent with a stop-motion shoot.

Someone pointed this out in the YouTube comments, but that stop-motion "quality" you're describing can easily be described away by YouTube's new stabilization feature. It tends to create this weird steadycam/otherworldly effect on videos.

No doubt in my mind that both videos are completely authentic; why would ONE video be real and the other not be? Least of all when the other reveals that there are several clicks and the ball uptake/release appears to happen in stages? One's just faster, which is clearly how the machine is meant to be operated.
posted by disillusioned at 11:26 PM on August 15, 2012


This video is no longer available because the YouTube account associated with this video has been terminated due to multiple third-party notifications of copyright infringement from claimants including:

Lawrence Braden Childers
Vikram Singh Yadav
thedzer

posted by anazgnos at 9:23 AM on August 22, 2012


For example, check out these tricks, the Haunted Deck and Drift...

Holy crap...Drift looks impressive as hell.
posted by Thorzdad at 6:55 AM on August 26, 2012


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