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Quadrocopters Throwing and Catching an Inverted Pendulum
derGoldstein writes "We've seen some very impressive aerobatics performed by quadrocopters before, but this is getting ridiculous. Robohub points to the latest advancement from the Flying Machine Arena, which developed algorithms that allow quadrocopters to juggle an inverted pendulum. One of the researchers working on it said, 'We started off with some back-of-the-envelope calculations, wondering whether it would even be physically possible to throw and catch a pendulum. This told us that achieving this maneuver would really push the dynamic capabilities of the system. As it turned out, it is probably the most challenging task we've had our quadrocopters do. With significantly less than one second to measure the pendulum flight and get the catching vehicle in place, it's the combination of mathematical models with real-time trajectory generation, optimal control, and learning from previous iterations that allowed us to implement this.'"
It don't mean a thing if they don't compute that swing.
rewriting history since 2109
It is now clearly obvious: in the future, the weapon of choice to fight robots will be an aluminium baseball bat.
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This is great, now American will be able to kill arab civilians in a fancy way
What, by using a Kraut stick grenade as the inverted pendulum in question?
Ezekiel 23:20
Because the round bits on the end act as pivots that are below the center of mass.
Because an inverted pendulum is a class and a stick is a particular instance (as it would be a drunkard).
Questions raise, answers kill. Raise questions to stay alive.
Nope, that's the Daleks' way.
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It's about sounding "science", as much as it a well defined scientific concept. An inverted pendulum is a well defined controls problem, where you take an unstable system and make it stable with your control laws. This is often solved in one dimension as part of undergraduate controls classwork with a cart and a stick balanced above it. The description of throwing and catching inverted pendulums perfectly describes what they are doing.
On the other hand, if they said they were throwing and catching a stick, I'd assume they were simply catching it. The balancing the unstable system with their control laws would not be assumed. Hope this helps.
This looks like it was achieved using motion capture equipment, as seen by the usage of retro-reflective balls (see them shine at 1:44). If that's the case, it would imply that the computing was done remotely. Motion capture gear typically works at 120 frames per second, which would give the system enough time resolution to figure this out on the fly with a decent PC on the back-end.
It'll be a while before the quadrucopters can do this in their own but the program figuring out the catching move is impressive nonetheless.
Nothing is enough for whom enough is too little - Confucius
This was a triumph!
I'm making a note here:
"HUGE SUCCESS!!"
It's hard to overstate
my satisfaction.
Aperture Science:
We do what we must
because we can.
For the good of all of us.
Except the ones who are dead.
But there's no sense crying
over every mistake.
You just keep on trying
till you run out of cake.
And the science gets done.
And you make a neat gun
for the people who are
still alive.
I'm not even angry...
I'm being so sincere right now-
Even though you broke my heart,
and killed me.
And tore me to pieces.
And threw every piece into a fire.
As they burned it hurt because
I was so happy for you!
Now, these points of data
make a beautiful line.
And we're out of beta.
We're releasing on time!
So I'm GLaD I got burned-
Think of all the things we learned-
for the people who are
still alive.
Go ahead and leave me...
I think I'd prefer to stay inside...
Maybe you'll find someone else
to help you?
Maybe Black Mesa?
Find More lyrics at www.sweetslyrics.com
That was a joke Haha! Fat Chance!
Anyway this cake is great!
It's so delicious and moist!
Look at me: still talking
when there's science to do!
When I look out there,
it makes me GLaD I'm not you.
I've experiments to run.
There is research to be done.
On the people who are
still alive.
And believe me I am
still alive.
I'm doing science and I'm
still alive.
I feel fantastic and I'm
still alive.
While you're dying I'll be
still alive.
And when you're dead I will be
still alive.
Still alive.
Still alive.
Do you have pendulums in your house? PAK CHOOIE UNF.
At one point in the film there is a cloud of ???. Is this the staff being ground up due to an apparent miss?
The end of the staff has a small balloon on it, filled with powder -- see explanation further down the linked page. Sounds like a small hacky-sack with a rubber (grippy) surface. They call this a "damper" and one popped open.
Adding my compliments to the rest -- very cool demonstration of control theory.
Typing "inverted pendulum" into google would have saved you some embarrassment
Not from not knowing what an inverted pendulum is, there's no shame in that.
The shame is from:
a) Not knowing how to use google
b) Trying to sound smarter than people who can do the math needed to toss inverted pendulums between quadcopters (which they designed and built).
No sig today...
That link points out that a human is also an instance of an inverted pendulum. I think I see some real potential for this now.