Real-time reconfigurable elastic wave propagation and energy harvesting characteristics of self-powered magnetic-electro-elastic metamaterials

Abstract Real-time reconfigurable elastic wave propagation behaviors of intelligent metamaterials have attracted fast-growing attention to provide a foundation for designing adaptive and customizable devices. However, designing a simple and efficient field-control method and addressing the energy supply issue for external field excitation remains a significant challenge. We propose a self-powered magnetic-electro-elastic metamaterial (MEEM) composed of magnetostrictive pillars and piezoelectric sheets arranged on an elastic beam to reveal the real-time dynamic regulation of band gap and defect state of flexural waves by applied magnetic field, the vibration energy harvesting induced by defect state can be served as a power source to supply energy for the whole system. First, the tunable voltage field and band gap of flexural waves is studied. Then, reconfigurable single and double defect states are successfully found in real-time by adjusting magnetic field, the energy harvesting induced by defect states has also been studied. The results show that as uniform magnetic field increases, the frequencies of single and double defect states increase. The location spacing of double defects should not be ignored for regulating the frequency of double defect states. The total voltage and power harvested from all unit cells are significantly higher than those harvested solely at the defect, which can be affected by the superposition of magnetic field, prestress and defect location. The proposed self-powered MEEMs open a new possibility for real-time reconfigurable elastic wave propagation and energy harvesting, promoting the design of customizable self-powered elastic wave devices involving guiding, sensing and monitoring.