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wierdscience
06-02-2011, 11:10 PM
Pretty neat-

http://www.thesun.co.uk/sol/homepage/video/virals/3614856/This-robots-got-balls.html

mochinist
06-02-2011, 11:19 PM
that is insanely cool, thanks

Evan
06-03-2011, 12:27 AM
I can almost smell the smoke from the servoes....

JRouche
06-03-2011, 12:55 AM
Thats pretty darn cool. I wonder what other machines are out there that do Human type motions that some us never knew existed.

Yeah, there are pitching machines, and many other similar machines not to mention welding/painting robots.

But how about a Yoyo flipper machine that is perfect and does repeated flips ( maybe even a walk the dog in between every once in a while) Im sure it can be done. And to make it cool looking it should flip the yoyo to mimic how we do it.

Makes me wonder where CANT a machine be made and programed to mimic (physical motions) our motions. Even some of the walkers and jumpers are out there. How bout a ladder climber? So many interesting machines. I love this stuff.

Mimic machines, I love the idea. JR

darryl
06-03-2011, 02:44 AM
How about introducing some cross winds- then see if the machine can still catch the balls

philbur
06-03-2011, 05:17 AM
It's not clear if the machine just goes to a preset position to receive the ball or if it adjusts it's position based on feed-back from the ball trajectory. The latter would be very, very cool.

Phil:)

Evan
06-03-2011, 05:59 AM
My understanding of the text is that the point of the machine is to demonstrate the accuracy and repeatability of the system. In other words, there is no need to compensate for slight differences in trajectory since it isn't enough to matter.


The latter would be very, very cool

And orders of magnitude more difficult to accomplish.

Jaakko Fagerlund
06-03-2011, 05:59 AM
Didn't investiagate/read about that robot, but I suspect it is using machine vision to see where the next ball is coming. On the video you can see it loses one ball and still continues flawlessly.

Evan
06-03-2011, 06:18 AM
From the source: It does use visual feedback to compensate for the ball position.

http://dce.fel.cvut.cz/juggler/

Your Old Dog
06-03-2011, 06:41 AM
I'm surprised that it needs visual feedback at all. Thought if each ball were propelled in exactly they same way that they would all follow exactly the same trajectory? At any rate, neat video! Wonder if it does bills?

Arcane
06-03-2011, 06:45 AM
Here's a couple of vids that show an even more impressive display of what a robot hand/arm can do. Check out the last 20 seconds of the first vid!

http://www.youtube.com/watch?v=-KxjVlaLBmk&feature=player_embedded#at=16

http://www.youtube.com/watch?v=vu6APoC0IOA&feature=related

DICKEYBIRD
06-03-2011, 07:46 AM
Pretty cool stuff. Child's play compared to this: http://www.youtube.com/watch?v=3CR5y8qZf0Y&feature=player_embedded#at=35

There's a website showing may other amazing things they can do...can't find it right now.:(

philbur
06-03-2011, 11:12 AM
The last 20 seconds of that first video, where it Tosses the mobile phone in the air and then catches it, has to be pretty spectacular.

Phil:)


Here's a couple of vids that show an even more impressive display of what a robot hand/arm can do. Check out the last 20 seconds of the first vid!

http://www.youtube.com/watch?v=-KxjVlaLBmk&feature=player_embedded#at=16

http://www.youtube.com/watch?v=vu6APoC0IOA&feature=related

Alistair Hosie
06-03-2011, 02:44 PM
This would be great fitted to body armour to fend of bullets. Alistair

RPM22
06-03-2011, 03:36 PM
While the previous examples were obviously very hi-tech, perhaps these are more within our reach ? His name is B Litwin, and he appears to be a genius?

http://www.youtube.com/watch?v=Q0OTX4IwSOo
http://www.youtube.com/watch?v=dauoL7U7zEU&feature=related
http://www.youtube.com/watch?v=Yngc_QupghM&feature=related

Enjoy

Richard in los Angeles

Evan
06-03-2011, 06:00 PM
What amazes me about the ball juggler is that the real time visual feedback system runs under Windows.

topct
06-03-2011, 06:07 PM
Then something like this is not so far fetched,

http://www.youtube.com/watch?v=hyCIpKAIFyo

Evan
06-03-2011, 06:16 PM
That is insane. I do a lot of computer graphics including animations but I have no idea where to even begin for something like that. It must be programmatically calculated. The software must be intense.

topct
06-03-2011, 06:29 PM
That is insane. I do a lot of computer graphics including animations but I have no idea where to even begin for something like that. It must be programmatically calculated. The software must be intense.

And that's an old one.

Weston Bye
06-03-2011, 06:40 PM
That is insane. I do a lot of computer graphics including animations but I have no idea where to even begin for something like that. It must be programmatically calculated. The software must be intense.


I have the DVD. They describe the software in one of the extra feature cuts. It is intense. They basically created the visual insturment. Feed in the music and it creates the video. The basic premise seems easy enough (for them), but gets more complicated as the view pans around.

Evan
06-03-2011, 06:54 PM
It's all about the timing. Creating the visual environment is relatively easy. Making the timing work out isn't. Each ball has a particular trajectory to follow and the trajectory must obey the physics engine before anything else or it won't look right. The time it takes for the ball to reach a particular target must then be calculated which is no simple matter when the target is also moving. Every last ball that is fired must have a timing calculated so that it can be fired the correct number of frames in advance in order to strike the target at the right time for the note produced. Further, all trajectories must be planned so that they do not intersect at the same time and place in the simulation. The number of variables that it takes to keep track of all that boggles my mind, never mind that it isn't done in real time. I suspect the pre rendering calculation time is very high.

whitis
06-04-2011, 03:09 PM
Evan: it is a very impressive animation and a lot of work but not for the reasons you cite.

The timing is pretty easy, actually. You have your midi events, you process them with the lead time needed by each to schedule your process threads (or equivalent) handling each ball. The lead time does not need to be exact - it needs to be slightly greater than or equal to the travel time. You pass each thread the intercept time and it can calculate the exact starting time.

The moving objects weren't that bad, that I saw. For example, the xylophone pieces moving along the track can easily be calculated even if you were trying to hit the moving target. Turns out, the trajectory and time of travel is constant and they schedule the xylophone pieces themselves to arrive when they want the notes to play and just need to launch the ball a fixed time before.

I am not convinced they have even implemented collision detection let alone collision avoidance. The trajectories are generally non-intersecting or have a low probabilty of collision. Any low probability collisions that actually would have occurred may have been handled manually by asking for an alternate trajectory for that note (i.e. shoot harder at a higher angle a little earlier).

Looks to me like they were smart enough to avoid the things that would make the simulation really difficult. I had figured out how to program it before the video was over.

jugs
06-04-2011, 06:31 PM
Not only is that clever ...... it's also a pleasant tune :D

john
:)

topct
06-04-2011, 06:57 PM
Let us not forget the real thing,

http://www.youtube.com/watch?v=njG_dQC-cnk&feature=related

Just thought I'd sneak this in. :D