Asked by: William Ho, by email
In the movie, Robert Downey Jr achieves superhuman strength by building a power suit tooled up with actuators that assist his limbs. He can kick his way through steel doors and throw heavy objects around with his enhanced arms. Real-life inventors are indeed working on powered suits.
An American firm called Sarcos has developed an aluminium exoskeleton for the US military. Soldiers clip themselves in and actuators on their arms help them effortlessly lift weights of up to 100kg. The legs are assisted by motors that help soldiers sprint up steep ramps with ease. In Japan, Honda has built a similar exoskeleton where the wearer's weight is supported by a seat connected to mechanical devices that strap on to the legs. The firm hopes it will aid people who have difficulty walking. In the Iron Man movie, Downey Jr's suit is also jet-powered, allowing him to dogfight with two fighter planes. But the real-world inventors are still working on that.
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