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arXiv · 1909.13224

Experimental observation of non-reciprocal band-gaps in a space-time modulated beam using a shunted piezoelectric array

Jacopo Marconi·Emanuele Riva·Matteo Di Ronco·Gabriele Cazzulani·Francesco Braghin·Massimo Ruzzene
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Abstract

In this work we experimentally achieve 1 kHz-wide directional band-gaps for elastic waves spanning a frequency range from approximately 8 to 11 kHz. One-way propagation is induced by way of a periodic waveguide consisting in an aluminum beam partially covered by a tightly packed array of piezoelectric patches. The latter are connected to shunt circuits and switches which allow for a periodic modulation in time of the cell properties. A traveling stiffness profile is obtained by opportunely phasing the temporal modulation of each active element, mimicking the propagation of a plane wave along the material, therefore establishing unidirectional wave propagation at bandgap frequencies.

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Jacopo Marconi, Emanuele Riva, Matteo Di Ronco, Gabriele Cazzulani, Francesco Braghin, Massimo Ruzzene. 2019-09-29. Experimental observation of non-reciprocal band-gaps in a space-time modulated beam using a shunted piezoelectric array. https://doi.org/10.1103/physrevapplied.13.031001

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