A team graduates of Carnegie Mellon University in the US have built a mechanism that can be integrated into shoes and turns them into chargers smartphones. 
The mechanism is called SolePower Insoles and according to its makers if placed on a pair of shoes the owner of them walking a total of one hour with them will be able to fully charge his device.
The kinetic energy of the feet is transferred to the mechanism by activating a mini-generator which charges the phone's battery via a cable. In the first phase the mechanism has proven to be functional integrated in sports shoes but the researchers they claim it will be able to work on other types of shoes as well.
