Eventos Anais de eventos
MECSOL 2022
8th International Symposium on Solid Mechanics
Exploring programmable defect modes in electromechanically coupled metastructures
Submission Author:
Carlos De Marqui Junior , SP
Co-Authors:
Danilo Beli, Carlos De Marqui Junior, Renan Lima Thomes
Presenter: Carlos De Marqui Junior
doi://10.26678/ABCM.MECSOL2022.MSL22-0216
Abstract
In this work, we propose a piezoelectric metamaterial beam with a periodic array of local electromechanical resonators to localize and transfer bending vibration energy. The motivation is to open new possibilities for programmable wave localization and vibration manipulation using smart electromechanical metamaterials with applications that may involve guiding, sensing, monitoring and harvesting. Differently from traditional metamaterials with fixed functions, smart metamaterials can be programmed by updating the electrical properties without the drawback of affecting the mechanical design. This feature opens possibilities for a superior wave and vibration control in architected materials since the mechanical properties can be modulated in time. A finite element approach based on Euler-Bernoulli theory for a piezoelectric bimorph beam is used to model and to investigate the wave and dynamic behavior of the smart metamaterial. Due to coupling physics (i.e., electrical and mechanical domains), a modified formulation has been used to apply the Bloch-Floquet theory in a super-cell to investigate the band gap and the defect mode. The periodic configuration, where all resonant circuits are tuned at the same frequency, has band gap where the flexural wave cannot propagate. However, a spatial defect is created when one of the resonant circuits has a different frequency compared to the other cells. Therefore, a defect mode appears inside the band gap. Since this mode is protected by the band gap of the neighboring unit cells, vibration energy localizes spatially at the defected unit cell. We show that the defect can be modulated in space-time by updating the electrical resonance of subsequent unit cells in a smooth and synchronized strategy. As a consequence, the vibration energy is also transferred along the metamaterial beam, and hence, perfectly localized according to the final defect position. The space-time wave localization in the electromechanical metamaterial beam is also experimentally demonstrated.
Keywords
Piezoelectricity, Programmable metamaterials, Space-time modulation, Smart metamaterials
