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Universal Manipulator Does Chess
SillyWilly writes: "A while ago a story was posted here about a vibrating plate capable of sorting color poker chips, and there was much ado about the videos being real. Well, a new cool demo involving chess pieces is out, done by a fellow called Neil Aldrin, who is hacking away at Dan Reznik's (the original inventor) cool contraption."
The movies aren't faked. I used to work for the same professor (John Canny), and I saw the table in action. It's pretty cool stuff, though it could go a lot farther with some more math work on the field created.
Yes, the table is real. Yes, it works. Yes, it could be better. This is research... this is expected!
Lea (who used to work on cs theory and robotics, and now works on cs theory and crypto)
but I can't do this. What's cool about this isn't the fact that they have figured out how to have a computer sort poker chips. It's the fact that they can do it by simply shaking the table! I challenge you to find any human that can simultaniously pass the salt to one end of the table while passing the pepper to the other end of the table by merely shaking it! There is nothing humanlike about this at all.
A big use for this kind of thing is for part feeding, that is a method of orienting parts on an assembly line. There is mention of this on Dr. Resnik's web page. Basically, you have the problem of presicely orienting a whole whack of (possibly complicated) parts as fast as you can to present them to the next stage in an assembly process.
Yes, a robot can accomplish this, but because of the motion that is involved they are slow, and because of the optical recognition involved they can bit, uh ... touchy :)
One method of dealing with part orientation is by things called bowl feeders. They are a bit hard to describe in type, but imagine that you have a big steel drum with a spiralling track up the inside of the drum. By vibrating the drum you can make the parts you are trying to orient climb up the track (beleive me, this sounds wierd, but it actually works). By changing the shape of the track you can force incorrectly oriented parts to fall back into the bowl, thus filtering out parts that are correctly oriented. So, only parts that are correctly oriented arrive at the top of the drum.
It's not quite as simple as that, but that's the general idea. Now, as well as this works (when it works), the problem is that whenever you change the shape of the part, you need to build a new bowl feeder! And building these things is not simple (or cheap).
I beleive what Dr. Reznik is trying to do with this experiment is not to prove that you can move poker chips around, but that you can build a programable solution to this problem; you can build one machine that will sort anything, given the correct programming of the controllers, thus alleviating the cost of prototyping things like bowl feeders.
So, to my mind, it's actually pretty spiffy, despite what others are saying here.
I know I've left out some details, and I certainly haven't researched Dr. Reznik's work, but hopefully I've given you (and some of the /. detractors) some idea where this work is probably headed.
The only thing I find a bit perplexing is, if he is proceeding towards the end that I've described, is how he is going to do this in three dimensions. Sure, he can rotate things in two dimensions, but what about more complicated parts?
I should also add that watching one of those bowl feeders in action is actually pretty creepy at first. Parts move up the track, but nothing else seems to be moving (the vibration rate is quite high, so you don't really see it). Mind you, they are freakin loud :)
If I could manipulate entire universes, I'd find chess kind of boring.
Recognize what they're doing. They're vibrating a rigid plate in such a way that one object, out of many, moves. The system that drives the plate can produce both small rotations and translations. The vibrations have arbitrary waveform, and are generally asymmetric. It's the asymmetry that produces motion. That's all.
I could see this working for two objects, because you could vibrate the plate such that the center of rotation was under the one you didn't want to move, so it didn't go anywhere. But I had no idea how they make this work for N objects.
The novel result in the thesis is section 6.1. Figure out how a "jet" vibration works, and you'll understand the whole thing. The basic idea is that a rotational vibration centered on the point at which motion is desired is superimposed on a translational vibration in the desired direction of travel. When both vibration functions are suitably chosen, there's a very unexpected property: the feeding velocity is small everywhere except near the center of rotation.
This is counterintutive. You'd expect the rotational effects to be biggest far from the center of rotation, and zero at the center of rotation. Apparently the idea is that the forces induced by rotation interfere with the translational vibration that makes objects move. What puzzles me is that they're able to achieve zero feeding motion over most of the entire plane. But look at figure 6.2 in the thesis, showing the jet field.
That's really neat. But I don't get it intutively yet. Can anybody else explain it more clearly?
Yeesh. Normally I wouldn't bother posting this, but I've read 4 comments about how the propriatary bastard is offering the videos only in windows media format! Good lord. Read a little further. It's in good ol' MPG1 too.
They clearly only are posting in windows media because it uses so much less bandwidth. Actually windows media uses MPG4 as it's underlying implementation, which you can play in linux anyway if you really care to. Yeesh!
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the pen is mightier then the sword. the sword is mightier then the court. the court is mightier then the pen.
I hope someone who understands robotics better than me can explain -- what is so special about this device? I saw the chess and poker chip demos and I was impressed, but the same could be accomplished using a robotic arm, probably in less time. Can someone in the know explain the import of this technology? I'm sure it exists but I haven't read enough on the topic to see it plainly...
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when computers and machines do humanlike tasks such as basic sorting of real world objects...
and they don't get all hot and bothered when they do non-machine like tasks, such as lifting big cars and things?
Robots that walk like people, human facial expressions on computer-graphics simulation.. they all generate so much interest among technical people.
Perhaps, not being a technical person, I am more interested in the great alienness of machines. I am interested in earth movers at mines; the Big Dig in Boston; construction cranes; auto assembly lines; mainframes; enterprise-class servers; billion dollar electronic fund transfers.
The replacement of humans in industrial processes with machines has always been an object of industrial design. The assembly line replaced the guild style craft. Instead of creating little portable machines that aided the watchmaker and the bootmaker in their old craft methodologies, inventors remade the ways of creating goods; those guild methods were replaced by roboticized methods of manufacture.
I would rather see a chip in the head of the watch maker that gives him eagle eye vision, or an augmentation of intelligence or emotional sales skills in a salesperson, than something that would eliminate these people from their industries.
Goat sex free since 2001
Ok, first the full disclosure. I'm a grad student who worked with both John Canny (the advisor involved) and Dan Resnik (the builder of this cool device). http://www.cs.berkeley.edu/~jfc/
The objections that I'm seeing seem to be of the following:
* "It's not real--the videos are fake."
No, it's real. The basic principle is this: if you take a table and shake it, stuff moves a little. If you shake it in a different direction, stuff moves in a different direction. Dan has figured out a pretty cool way of quantifying all this. He does a vector addition of several different shakes, and is able to therefore target the shaking.
* Why is it cool?
Well, first, because it's not obvious that it works. This is tricky math.
* Yes, but why THIS?
Because robot arms are a pain, and only manipulate one thing at a time, and they need a lot of elbow room, and a lot of motors, and they have to touch things. This requires four motors that JUST pulse in and out. It works on a flat table. Nothing touches except the table surface. This would be perfect for carefully-controlled environments like clean rooms (where you want to minimize the amount of stuff in the room), hazardous materials, and delicate objects. There's very little complexity, and because it's just a bunch of (tuned) vibrations, you could slap up a new one against a floor and it works.
The chess demo is just showing that one can comfortably manipulate a large number of items.
* Does anyone need to sort multiple things?
All the time. Factory floors separate out rejects from working models. Recycling centers separate cans from bottles. Usually, they hire people to sort the stinking messes apart, and they use clever special-built machines to separate metal (use a magnet) from glass (heavier than plastic when crushed) from paper. This sorts on a smooth--therefore easily cleanable--surface.
Dan now works for Siemens TTB, who are, among other things, very interested in small motors.
* My toy did this.
Yes, it did. But it did it in an extremely constrained way, and it probably took a really practiced flip of your wrist. And it probably did it in one dimension. (Dan has a little plastic train set that works on this principle).
* This eliminates human jobs
Not necessarily. It could work well in conjunction with a human job. Why do that annoying RSI-inducing reach/grab/sort when you can sit behind a desk, look at a video camera, and tick off the items on a screen? After all, image recognition isn't too good yet. The machine is responsible for the reach/grab/sort, and you don't have to wear a bunny suit.