A quasi-zero-stiffness metastructure for concurrent low-frequency vibration attenuation and energy harvesting

• Shape functions for cosine-shaped beam under a transverse force are proposed. • A novel QZS piezoelectric metastructure with two functions is designed. • Electromechanical coupling models decipher mechanical and electrical responses. • The finite element results verify the theoretical predictions. Metastructures have been extensively studied for vibration attenuation, wave manipulation, and energy conversion. However, achieving simultaneous vibration attenuation and energy harvesting in low-frequency and ultra-low-frequency regimes remains challenging due to limitations in conventional designs. This study proposes a novel dual-functional quasi-zero-stiffness (QZS) metastructure that integrates low-frequency bandgap generation and piezoelectric energy conversion using polyvinylidene fluoride (PVDF) films. The metastructure is optimized for low-frequency, low- amplitude conditions typical in engineering applications. A nonlinear electromechanical coupling model is developed to describe its dynamic and electrical behaviors, with governing equations solved numerically using the fourth-order Runge-Kutta method and validated via finite element simulations. Parametric studies investigate the influence of key design parameters on vibration attenuation and energy harvesting performance. Results demonstrate that the QZS metastructure effectively suppresses low-frequency vibrations while achieving efficient energy conversion, leveraging its unique combination of bandgap formation and piezoelectric mechanisms. This work provides valuable insights into the development of advanced metastructures for low-frequency vibration control and energy harvesting in practical applications.