How does a tiny generator turn vibrations into electricity?

AI Thread Summary
The tiny generator operates by using cantilever-mounted magnets that induce a current in a copper coil when vibrations occur. As the magnets shake more than the copper coils, the changing magnetic flux through the coils generates electricity according to Faraday's law of induction. This mechanism is similar to how magnetic pickup cartridges function in vinyl record players, which also rely on Faraday's principles without needing an external power source. The design represents a compact version of existing technology aimed at harnessing vibrational energy efficiently. Understanding this process highlights the potential for small-scale energy generation from everyday vibrations.
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I know what it does but what's the mechanism that turns vibration into electricity?
 
The key word you want to search is http://en.wikipedia.org/wiki/Piezoelectricity"
 
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That generator is not piezoelectric. The URL the OP linked to describes how it works very well:

"The sugar cube-sized generator, a smaller version of a design already commercially available, uses cantilever-mounted magnets to induce a current in a copper coil"

Basically, magnets shake around more than the copper coils. Magnetic flux through the coils changes, which induces a current in the coil via Faraday's law of induction.
 
Those readers who are old enough to remember 33 RPM vinyl records may recall the magnetic pickup cartridge:
http://en.wikipedia.org/wiki/Magnetic_cartridge
This pickup came in two configurations; moving magnet and moving coil. Neither had any battery or external power supply. Both work on the Faraday induction law.
Bob S
 
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