Humans have a limited battery life!

A lot of research has gone into increasing the capacity of humans to do physical work. This includes development of exoskeletons.

The first exoskeleton was invented and patented in 1917 by a US inventor Leslie C. Kelley. The exoskeleton operated on steam power with artificial ligaments acting in parallel to the wearers movements.With the pedomotor, energy could be generated apart from the user. 

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