Ball catching robot, 80% accuracy in 5 milliseconds (w/ video)

April 29, 2011 by Katie Gatto weblog

( -- DLR, an aerospace agency based in German, has modified its flagship robot, known as the Rollin’ Justin, in order to make it into a lean, mean, catching machine. The Rollin’ Justin's modifications allow the machine to catch balls that are thrown in its direction with an accuracy rate of about 80%. The Rollin’ Justin's robots accuracy rating is better than the average uncoordinated human. It is certainly better than this reporters accuracy rate. It is not as good as say, a Major League Baseball player, but then again most of us cannot say that we are as good as the pros either. Considering they also have near unlimited stamina, at least until the battery runs out, it may be a great partner for the standard game of catch, or for the position behind the batter.

The video will load shortly

The machine can actually catch up to two balls at once, and while this may not sound like a lot on paper, but just try doing it in the back yard. It is not exactly an easy task. The will, when the balls are released, calculate the flight path of those two balls, and then position its hands into a catching position that is within 2 centimeters of the point where the ball is expected to be, in about just 5 milliseconds. The system does work with the help of external computers. They are needed in order to handle the processing and make the calculations possible in real time.

The Rollin’ Justin weighs about 45kg , and it is equipped with a 3D camera system that allows it to pinpoint the objects distance, which needed in order make the calculation. The robot is built with 43 joints, with 5 in his torso, 7 in each of the arms, and 12 in each hand. It is also equipped with a total of 84 sensors.

Explore further: Key to Robonaut 2's dexterity is human-like hands

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not rated yet Apr 29, 2011
Ninja robot soon to follow...I'm sure of this.
5 / 5 (3) Apr 29, 2011
Video didn't work for me. Try this link

not rated yet Apr 29, 2011
Video didn't work for me. Try this link


They should get together with these researchers

5 / 5 (2) Apr 29, 2011
Next they'll be catching bullets.
not rated yet Apr 29, 2011
antialias: In the WWIII, they will. ;)
not rated yet Apr 29, 2011
Great videos, gentlemen! Kind of makes me want to make a robot.
5 / 5 (1) Apr 29, 2011
can an an electric motor joint achieve speeds necessary for bullet catching? even if it was possible to calculate bullet position and trajectory instantly, what kind of motors would handle the arms?
3 / 5 (4) Apr 29, 2011
Humans average about 215ms for visual reaction, with a limit towards 100. A housefly, because of its tiny optical nerve distance and relatively limited processing, can manage 20 milliseconds before responding to stimuli. At 5ms, This machine thinks 4 times quicker than a fly apparently.

With some modifications, this machine COULD potentially block bullets, even with just human speed. If it only has to move an arm 50cm to block the bullet, and it can spot a 450m/s bullet at 2.25 meters out the barrel, then, at a perfectly achievable arm speed of 20m/s, it could grab the bullet when fired from 13.5 meters (11.25 meters plus reacting/calculating time) away...

Now, why you'd want to "grab a bullet" when it's the equivalent of getting shot in the hand, I don't know. Future death robots will be better off just dodging.

Actually... robot bodyguards, anyone?
not rated yet Apr 30, 2011
cool stuff. will be even more impressive when it throws them back.
After all, playing catch is so much more fun.
not rated yet May 01, 2011
The bullet would disintegrate in your grasp even if you caught it. The robots would need hands/shields made of a hardened material immune to bullet impacts. Then they could block bullets.

Strap one of those badboys on your back and laugh as the terrorists try to shoot you.
not rated yet May 01, 2011
The robot could just tap the bullet to send it off course. This way most of the kinetic energy isn't transferred to the hand.
not rated yet May 01, 2011
More likely the robot will kill/disarm the gunman before he can even tell his little finger to pull the trigger.

I wonder how fast robot legs will be able to get to 60 mph?

"It's ok Chris. I am pretty sure she would have crushed your scrote into a Diamond with her robot strength arm." - Stewie
not rated yet May 01, 2011
Cool. Now rich dads can buy a standin.
not rated yet May 04, 2011
Now if they can get 'em to throw and swing a bat, we'd have BASE WARS in no time!
Rollin' Justin actually kinda looks like the one batting... wierd.

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