Vibration energy harvesters can be connected to electronics in garments and footwear that are able to track physical parameters such as speed, movement and temperature. It is yet really challenging to generate in this way enough energy to power today's applications. Fraunhofer IPMS developed an energy harvester device able to power electronic devices with improved efficiency. »The device able to convert mechanical to electrical energy is based on thin films of dielectric polymers of large relative permittivity. 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. Additionally, the developed device is small, flexible and easily embeddable into, for instance, the sole of a shoe,« says Dr. Florenta Costache.
A first device demonstrator of a polymer energy harvester embedded in a shoe is now available. This is able to generate several µW of power in a second when subjected to mechanical deformation of pressure and frequency range specific to human walking. The harvester circuit has been adjusted to power a transmitter module. Thus the system is able to generate mechanical power and, using that, to transmit telegrams at intervals of seconds. The harvester device and circuit can be adapted for other applications such as for powering wireless sensors (temperature, acceleration, pressure), for powering portable devices and monitoring various bio-data.
At Embedded World, the world's leading trade fair for embedded technologies to be held in Nuremberg from February 23 to 25, 2016, visitors can take a look for the first time at the above presented demonstrator. This will be displayed at the Fraunhofer IPMS booth 583 in hall 4.