Real Life steam powered arm.

Mechanical engineers at Vanderbilt University in the US, have created a prosthetic limb that runs on steam. Michael Goldfarb, the professor of mechanical engineering leading the effort, says the "power source is about the size of a pencil and contains a special catalyst that causes hydrogen peroxide to burn. When this compound burns, it produces pure steam. The steam is used to open and close a series of valves. The valves are connected to the spring-loaded joints of the prosthesis by belts made of a special monofilament used in appliance handles and aircraft parts. A small sealed canister of hydrogen peroxide that easily fits in the upper arm can provide enough energy to power the device for 18 hours of normal activity."

After getting the arm working with cold gas, the engineers tore it down and rebuilt it to operate on "hot gas" – steam that is heated to 450 degrees Fahrenheit by the hydrogen peroxide reaction.

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