New 'smart' shoes generate power from walking

Researchers have developed new 'smart' shoes that harvest power from the simple act of walking.
The shoes consist of a "shock harvester" that generates power when the heel strikes the ground and a "swing harvester" that produces power when the foot is swinging.
The technology could be used to power wearable electronic sensors without the need for batteries, 'BBC News' reported.
"We have tried to power a wireless transmitter and to power a simple sensor," said Klevis Ylli from HSG-IMIT, a research centre in Germany.
"One application we are working on is indoor navigation which means we have sensors within the shoe that measure the acceleration of the foot," said Ylli.

The energy harvesting devices generate power by exploiting the motion between magnets and coils.

As the magnetic field of a moving magnet passes by a stationary coil, a voltage is induced and an electric current is generated.
The energy the technology generates is still relatively small - in the three to four milliwatt range at the peak.
However, it is enough to power small sensors and transmitters, opening up a range of new applications.