Low and ultra-wide frequency wave attenuation performance and tunability of a new cruciate ligament structure

This paper presents two novel cruciate ligament structures with outstanding contributions in lightweight design of metamaterials, band gap tuning, and ultra-wide and ultra-low frequency vibration and noise reduction, as well as providing a new design idea. The novelty of this paper is manifested in various aspects, combining Bloch's theorem and finite element method to calculate the band gap, and using the transfer function to verify the evaluation; using structural optimization and applying active strain to test the structural tunability; and illustrating the wave propagation and band gap opening mechanism from the vibration mode and energy perspectives. The results show that the widest band gap can reach 5061.9 Hz after structural optimization and tuning, while the lowest can be reduced to 274.3-285.6 Hz, and the vibration attenuation peak is around -620, so the structure has excellent vibration and sound insulation effect, while the band gap can be widened and reduced under active strain. The opening of the band gap is closely related to the directionality and regionality of wave propagation, and the comprehensive analysis method of wave propagation provides innovative research ideas for wave propagation, and also provides theoretical and technical support for structure and band gap optimization.