Will Artificial Muscle Make You Stronger?

The first-ever human-robot arm-wrestling match seemed to mark an ignominious defeat for the robots. A girl who describes herself as“not very strong” had trounced some of the best artificial muscles that engineers have to offer.

But the researchers continue undaunted. Kovacs is back to making dielectric elastomer sheets that curve into complex shapes on command. Such a material could enable aircraft wings to change shape in flight, or emulate the undulating fins of a stingray to propel underwater vehicles. And Shahinpoor´s company is developing two medical devices: an adjustable band that would correct nearsightedness by squeezing the eyeball to alter its curvature and length, and a device that would help ailing hearts pump blood.

Just before I leave, I spy the Swiss engineers in the exhibit hall. They have taken apart their robot and clamped one of its actuator banks to a table. Two carboys, heavy with gallons of water, hang from the actuator bank. A sign with large red letters reads“Caution! High voltage!” With an air of mild disappointment, Kovacs explains that the rule requiring the arm to spring back prevented them from demonstrating their machine´s full strength. To simulate human muscles, which operate in pairs, one contracting while the other relaxes, the team had aligned their actuators to work in opposition, canceling each other out—except for a small differential, which represented the arm ´bot´s force. But now, released from the machine, their actuators could show their true power. One of Kovacs´s colleagues flips a switch, and the artificial muscle hoists and lowers the carboys—up and down, up and down.

“We didn´t win,” Bar-Cohen acknowledges. He adds:“Twenty-six seconds is maybe nothing.” Then, his voice rising with excitement, he continues,“But the first flight was 12 seconds. We have to remember that. A hundred years from now, who knows where we could be?”

In September 2003, Dan Ferber described the quest to make the most lifelike robot face ever.