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Juggling Robot Takes on Two Balls With One Very Fast Hand

This high-speed robot arm can juggle two balls at once. Can you?

2 min read
Juggling Robot Takes on Two Balls With One Very Fast Hand

It’s been a few years since we’ve seen any new tricks from those amazing high-speed robot hands from Japan. Now another Japanese group, at Chiba University, has managed to teach one of their dexterous hand-arm systems to repeatedly juggle two balls at once with an incredibly lifelike motion, presented yesterday at the 2012 IEEE International Conference on Robotics and Automation (ICRA).

This high-speed hand and arm combination is coupled to an even higher speed vision system that allows the robot’s controller to plan for catches and throws (up to nearly 2 meters in height) at a leisurely 500 frames per second. The hand has three fingers with two or three degrees of freedom each, while the arm has seven more (although not all of them are being utilized). To be clear, the system isn’t just doing a repetitive motion that results in a series of actions that mimic a juggling behavior: the balls are being tracked through the air, and a series of throwing calculations are made for each and every cycle.

At this point, the hand can only reliably execute about five catches in a row before it loses a ball. This is primarily because there’s no operating shoulder joint: the robot is restricted to what’s essentially a two-dimensional vertical plane of operation, so anytime a ball drifts even a little bit sideways, the robot can’t get to it. Also, there’s still some throwing instability going on, which is what causes the ball to gradually wander in the first place. The researchers plan to conquer the latter with a new throwing motion, and then move on to other types of juggling.

If you’re wondering what the point of all this is (or why it qualifies as “research”) the roboticists put it like this:

“[Juggling] is one example of a skillful and dynamic human-like motion. We believe that there is much to be learned from the analysis of fast and repetitive throwing and catching actions, and the experimental results of this study will shed light on the nature of skillful and dynamic manipulations by humans.”

Two Ball Juggling with High-speed Hand-Arm and High-speed Vision System, by Takahiro Kizaki and Akio Namiki from the Graduate School of Engineering at Chiba University in Japan, was presented yesterday at ICRA 2012 in St. Paul, Minn.

The Conversation (0)

The Bionic-Hand Arms Race

The prosthetics industry is too focused on high-tech limbs that are complicated, costly, and often impractical

12 min read
A photograph of a young woman with brown eyes and neck length hair dyed rose gold sits at a white table. In one hand she holds a carbon fiber robotic arm and hand. Her other arm ends near her elbow. Her short sleeve shirt has a pattern on it of illustrated hands.

The author, Britt Young, holding her Ottobock bebionic bionic arm.

Gabriela Hasbun. Makeup: Maria Nguyen for MAC cosmetics; Hair: Joan Laqui for Living Proof

In Jules Verne’s 1865 novel From the Earth to the Moon, members of the fictitious Baltimore Gun Club, all disabled Civil War veterans, restlessly search for a new enemy to conquer. They had spent the war innovating new, deadlier weaponry. By the war’s end, with “not quite one arm between four persons, and exactly two legs between six,” these self-taught amputee-weaponsmiths decide to repurpose their skills toward a new projectile: a rocket ship.

The story of the Baltimore Gun Club propelling themselves to the moon is about the extraordinary masculine power of the veteran, who doesn’t simply “overcome” his disability; he derives power and ambition from it. Their “crutches, wooden legs, artificial arms, steel hooks, caoutchouc [rubber] jaws, silver craniums [and] platinum noses” don’t play leading roles in their personalities—they are merely tools on their bodies. These piecemeal men are unlikely crusaders of invention with an even more unlikely mission. And yet who better to design the next great leap in technology than men remade by technology themselves?

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