Based on thin films of dielectric polymers of large relative permittivity, the device is able to convert mechanical to electrical energy. As compared with traditional piezoelectric configurations, this concept works non-resonantly and can be optimized for capturing energy from mechanical power sources in the low frequency range. The film is small, flexible and easily embeddable into, for instance, the sole of a shoe, as researchers have demonstrated.
The vibration energy harvesters could be connected to electronics in garments and footwear that are able to track physical parameters such as speed, movement and temperature.
The research lab has built a device demonstrator embedding the polymer energy harvester into a shoe, which is able to generate several µW of power in a second when subjected to mechanical deformation within pressure and frequency ranges specific to human gait.
What's more, the harvester circuit has been adjusted to power a transmitter module, transmitting data telegrams at several seconds of interval. In principle, the harvester device and circuit could be adapted to monitor various bio-data.
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