“Better, stronger, faster” bionic arms are being built using rockets.
It doesn’t have superhuman strength, but the new design is “closer in terms of function and power to a human arm than any previous prosthetic device that is self-powered and weighs about the same as a natural arm,” said researcher Michael Goldfarb, a roboticist at Vanderbilt University in Nashville.
The new prototype arm can lift about 20 to 25 pounds—three to four times more than current commercial prosthetic arms—and can do so three to four times faster.
“It has about 10 times as much power as other [robotic] arms,” Goldfarb said.
The rocket-powered arm also has greater dexterity and freedom of movement than any other prosthetic to date with twenty-one moving joints. Conventional prosthetic arms have only two joints, at the elbow and the “claw.” The protype has a wrist that can twist and bend, and fingers that open and close independently.
The radical design is similar to rocket systems that help the space shuttle and satellites maneuver in orbit. It employs a miniature rocket about the size of a pencil, and burns pressurized liquid hydrogen peroxide using iridium-coated alumina granules as catalysts, generating pure steam that forces pistons up and down, generating motion. Steam gets vented out through a porous skin-like cover, where it evaporates like normal sweat. “The amount of water involved is about the same as a person would normally sweat from their arm on a warm day,” Goldfarb said.
And it does it all quietly.
“It’s much quieter than I would have ever thought,” Goldfarb told LiveScience. “You can be in a room where people are talking at very low levels and never hear it. You have to be very quiet to hear this thing operate.”
Research has been funded by DARPA, which aims to develop better prosthetic limbs. Improvements in body armor and battlefield medicine have reduced the number of casualties from conflicts, but the side effect is a significantly increasing number of amputees, as has become evident among veterans of the ongoing war with Iraq.
DARPA’s goal is to have an advanced, commercially available prosthetic arm in two years. Unfortunately, Goldfarb is concerned DARPA funding might dry up for his team’s research because of the arm’s novel power source, which will probably take a long time to get regulatory approval due to safety issues.
Click here to see video of the arm in action, along with barely related Star Wars footage.
From Live Science.