Optimization of internal resonators for the design of quasi-periodic metastructures

Abstract

Metamaterials and metastructures have several applications such as noise and vibration attenuation, acoustic absorption and isolation, shock and vibration reduction, control and guiding of wave propagation, among others. They are inspired in phononic crystals that exhibit bandgaps, which are frequency ranges in which elastic and acoustic waves do not propagate. However, bandgaps in metamaterials depend on local resonator properties, that act as vibration absorbers, and not on the dimension of periodic cells. This concept has motivated the search for designed structures with local resonators based on metamaterials, so-called metastructures, that could exhibit bandgaps in the low-frequency range for relatively small structures. Several research groups have explored the viability of vibration absorbers in light flexible structures, including the use of distributed small mechanical vibration absorbers. There is a growing interest on the use of internal resonances to improve the control of structural vibrations, while there is also a need for advancement in the existing techniques and solutions. The main objective of this research proposal is to study the optimization of internal resonators in metastructures to improve the control of structural vibrations.