This mechanical prosthetic arm, developed by Michael Goldfarb and his colleagues of the Center for Intelligent Mechatronics at Vanderbilt University, is powered by a pencil-sized rocket that burns pressurized liquid hydrogen peroxide. The reaction, which is catalyzed by iridium-coated alumina granules, generates steam that forces the pistons in the arm to move up and down.
Conventional prosthetic limbs are powered by batteries. Rockets were employed here as an alternative, because of the weight of batteries needed to power a prosthesis for any reasonable amount of time.
The prototype rocket-powered bionic arm can be used to lift up to 25 lbs. This is 3-4 times more than currently available prostheses. It is also quite dextrous – the wrist can twist and bend, and each of the fingers can open and close independently.
The project has until now been funded by DARPA. But Goldfarb fears that funding from the agency might dry up, because of concerns regarding the safety of the prosthesis. The steam generated by the rockets can reach a temperatures in excess of 230 degress Celcius; although it is vented through a porous skin-like cover, it could still be a danger to both the user of the prosthesis and those in close proximity.
(Via Live Science)
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