Low-frequency bandgaps of 3D periodic superlight high stiffness resonant cavity plate–lattice structure with cubic symmetry

By studying the traditional plate–lattice structure and resonant cavity plate–lattice structure both with 3D cubic symmetry, it is proved that the resonant cavity plate structure can easily generate omnidirectional bandgaps with low frequency. The reason is attributed to the local resonance phenomenon of the latter. Based on this favorable property, unit cells of resonant cavities containing a multiple number M of 1-Rattle-Drum resonators and unit cells of cavities consisting of N-Rattle-Drum resonators (1 ≤ N ≤ 4) have been studied. The band diagrams and the mode shapes revealing that resonant cavity plate–lattice structure containing single 1-Rattle-Drum resonator is the easier one giving an omnidirectional resonant response at low frequencies. Effects of geometric parameters such as the Rattle-Drum width, the Rattle-Drum length, the thickness of the cylindrical plates and the radius of the cylindrical plates of the proposed single 1-Rattle-Drum resonators plate–lattice structure are investigated. By changing the geometric parameters, the resonant bandgap can be easily tuned to a lower frequency. The innovative translation of the theory into structural design concepts has given the structure the advantages of multi-characteristic integration of superlight, high stiffness, low-frequency noise reduction, low cost, ease of manufacture and high practicality, with potential applications in low-frequency vibration suppression in the aerospace industry.