There have also been several attempts to implement
generators which can harvest energy from human motion.
Most work has focused on the integration into the shoe as this has
the potential for significant energy harvesting [7,8]. For example,
Kymissis et al. [7] in MIT showed that PVDT and PZT piezoelectric
materials placed in the sole of the shoe were capable of generating
1 and 2mWaverage power duringwalking. Similarly Duffy and Carroll
[8] tested an electromagnetic generator integrated into a shoe
which could generate 500mV(rms) at a 5 Hz frequency.