Vibration-powered Generator

Vibration-powered Generator

A vibration powered generator is a type of transducer that converts kinetic energy derived from ambient vibration to electrical energy.

Magnets wobbling on a cantilever are sensitive to even small vibrations and generate microcurrents by moving relative to conductors due to Faraday's law of induction. By developing a miniature device of this kind in 2007, a team from the University of Southampton made possible the planting of such a device in environments that preclude having any electrical connection to the outside world. Sensors in inaccessible places can now generate their own power and transmit data to outside receivers.

One of the major limitations of the magnetic vibration energy harvester developed at University of Southampton is the size of the generator, in this case approximately one cubic centimeter, which is much too large to integrate into today's mobile technologies. The complete generator including circuitry is a massive 4 cm by 4 cm by 1 cm nearly the same size as some mobile devices such as the iPod nano. Further reductions in the dimensions are possible through the integration of new and more flexible materials as the cantilever beam component. In 2012 a group at Northwestern University developed a vibration-powered generator out of polymer in the form of a spring. This device was able to target the same frequencies as the University of Southampton groups silicon based device but with one third the size of the beam component.

Implants in heart muscles can use the heart's movement to generate sufficient voltage to act as a pacemaker, doing away with the necessity for regular battery replacements. Sensors placed in remote parts of a space shuttle or airliner can transmit data to a central receiver, such as a black box, even in the event of a total power failure. The pressure and temperature of wheels on a trailer could be monitored by placing sensors on the inside of the tyre. Factories producing any type of merchandise will benefit from being able to place maintenance-free sensors at all critical points.

Piezoelectric materials can also be used to harvest low levels of mechanical energy into electrical energy suitable for powering wireless sensors, low power microprocessors or charging batteries.