Periodic substructure for multi-frequency energy harvesting with single piezoelectric patch

Simple piezo benders are able to harvest energy almost only at their first natural frequency. Thus, their efficiency is good only in presence of harmonic excitation having frequency equal to their first natural frequency. In case of wide band excitation, instead, more complex solutions have to be sought for. In particular, various forms of nonlinearity have been investigated that allow to "bend" resonance peaks and thus convert kinetic energy into electric energy over a wider frequency band. Also harvester with more benders have been analyzed.