Experimental design and adaptive modulation of piezoelectric cantilever phononic crystals for vibration attenuation in vehicle subframes

To attenuate the vibrations in the vehicle subframe with changing target frequency, a piezoelectric cantilever phononic crystal (PC) and its adaptive modulation strategy are investigated in this paper. First, based on the cantilever-based PC structure, the bandgap characteristics are obtained by vibration transfer calculation and piezoelectric constitutive modeling. The experimental design of the piezoelectric cantilever PC is further conducted based on the parametric analysis results of structural dimensions and the targeted vibration frequency intervals required by the vehicle subframe. The modal experiments indicate that two local resonant bandgaps and one electromagnetic oscillation bandgap appear in the solved frequency interval, and both of them exhibit excellent consistency with the theoretical calculations. Finally, an adaptive bandgap modulation strategy is proposed by controlling the shunting circuit parameters, and the execution results demonstrate that the PCs employed in the vehicle subframe can effectively achieve vibration attenuation from the powertrain systems. Starting from the experimental design and adaptive modulation of cantilever PCs with piezoelectric materials, this research presents a novel framework for the application of acoustic metamaterials in the vibration mitigation of automotive structures.