An active tunable piezoelectric metamaterial beam for broadband vibration suppression by optimization

Piezoelectric metamaterials with shunt circuits have been widely studied for bandgap tuning. However, broadband vibration suppression is a great challenge in engineering applications. In this paper, a novel approach to address the challenge of achieving broadband vibration suppression in piezoelectric metamaterials with shunt circuits is presented. A piezoelectric supercell model containing multiple piezoelectric units is designed. In complex band structures, it is difficult to analytically couple multiple bandgaps to form a wider bandgap. An optimization method for a piezoelectric metamaterial beam with LR circuit is proposed to broaden the frequency range of vibration suppression. The electrical parameters of the LR circuit of the supercell are optimized by a genetic algorithm. Multiple locally resonant bandgaps are coupled to the Bragg bandgap by the optimization method. The attenuation rate can be customized, and the maximum bandwidth is obtained. It is verified that the optimized metamaterial can achieve vibration suppression in a wide frequency range by the transmissibility of the finite period metamaterial beam. Vibration suppression over a wide frequency range is verified by the finite element method. Finally, a synthetic circuit is used to simulate an adjustable inductor in an LR circuit, and the vibration suppression performance of the optimized metamaterial is experimentally verified. The experimental results show that the attenuation bandwidth of metamaterials is significantly broadened through optimization. The vibration suppression capability of wide frequency tunable is realized experimentally. This paper provides a novel way for broadband vibration suppression.