Piezoelectric thin-walled meta-plates via nonlinear semi-active electrical interface for low-frequency distributed broadband vibration control

To enhance the low-frequency distributed vibration control capabilities for lightweight thin-walled structures, this study reports a piezoelectric meta-plate with nonlinear semi-active electrical stiffness tuning. The proposed meta-plate consists of mechanical and electrical sections, with piezoelectric coupling at their interface. The distributed nonlinear semi-active enhanced SSDV shunting circuits are in the electrical domain, utilizing the piezoelectricity to affect the dynamic equivalent bending stiffness of the whole plate structure. Results show that the nonlinear semi-active electrical stiffness tuning of the proposed meta-plate can induce broadband electromechanical band gaps and enhance wave attenuation through band gap hybridization. The existence of these band gaps and their coupling effects are indirectly demonstrated by the meta-plate vibration transmission characteristics. In the case of a thin-walled meta-plate with a 1×5 array of periodic cells, there are 13 vibrational transmission modes within the 0–2 kHz range, with 12 significantly attenuated. The majority of vibration transmission modes are attenuated by more than 10dB, reaching a maximum of 64dB Additionally, the obtained equivalent damping ratio of the semi-active enhanced SSDV electrical circuit is below 0.4, so the nonlinear semi-active enhanced SSDV electrical shunt circuits are underdamped and exhibit high control stability. Therefore, the proposed semi-active distributed vibration control approach also has better robustness and reliability.