A novel magnetostrictive-material-based device concept to convert ambient mechanical vibration into electricity has been designed, fabricated, and tested. In order to harvest energy over a greater frequency range as compared to stateof-the-art devices, an L-shaped beam which is tuned so that the first two (bending) natural frequencies have a (near) two-to-one ratio is used as a mechanical transducer to generate nonlinear oscillations. Under harmonic excitation, an internal resonance or autoparametric, dynamic response can occur in which one vibration mode parametrically excites a second vibration mode resulting in significant displacement of both modes over an extended frequency range. A magnetostrictive material, Metglas 2605SA1, is used to convert vibration into electricity. Vibrationinduced strain in the Metglas changes its magnetization which in turn generates current in a coil of wire. Metglas is highly flexible so it can undergo large displacement and does not fatigue under extended excitation. Demonstration devices are used to study how this nonlinear response can be exploited to generate electricity under singlefrequency, harmonic and random base excitation.

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