Super-fast robotic arm catches items in midair

Watch this new mechanized arm learn how to field objects thrown its way through a process of trial and error.

Michael Franco
Freelancer Michael Franco writes about the serious and silly sides of science and technology for CNET and other pixel and paper pubs. He's kept his fingers on the keyboard while owning a B&B in Amish country, managing an eco-resort in the Caribbean, sweating in Singapore, and rehydrating (with beer, of course) in Prague. E-mail Michael.
Michael Franco
2 min read

Playing catch with a robot. Video screenshot by Michael Franco/CNET

C-3PO was a pretty cool robot, but I'm not so sure how good he would have been at fielding a fastball thrown his way. He's a bit stiff for sports.

But if he was updated with a new robotic arm developed by researchers at the Ecole Polytechnique Federale de Lausanne (EPFL) in Switzerland, he might just get a post-"Star Wars" job working for a minor league ball team. Researchers at the school have created a robot arm that can make fine enough adjustments -- in as few as five-hundredths of a second -- to catch a variety of objects thrown its way. Their research is being published on May 12 in the journal IEEE Transactions on Robotics.

The arm, which measures about 1.5 meters long and has four fingers including one that works like a thumb, was able to pluck a ball, an empty bottle, a half-full bottle, a hammer, and a tennis racket out of thin air. It uses a series of cameras to "watch" the objects coming its way and then makes the necessary moves to act like a star center fielder.

"Today's machines are often pre-programmed and cannot quickly assimilate data changes," said Aude Billard, head of the Learning Algorithms and Systems Laboratory at EPFL where the arm was programmed. "Consequently, their only choice is to recalculate the trajectories, which requires too much time from them in situations in which every fraction of a second can be decisive."

The arm was trained to catch the objects, which all have different sizes and centers of gravity, through a process called "programming by demonstration" that mimics the way in which people learn. Instead of using lines and lines of code to give the arm instructions, it was taught to catch by being physically manipulated by the researchers until it basically "got the hang" of catching things.

Billard adds that thanks to its speedy "on the fly" reaction time, the robotic arm could someday be incorporated into machines that protect humans by catching them when they're in danger of falling or by grabbing objects that are about to fall on top of them.

That, or we could just create a super-cool robotic baseball team. Who's with me?