As a fantastic vibration isolation method, acoustic metamaterial structures with vibration bandgaps at designed frequency ranges have attracted large attentions in last years. By introducing the acoustic metamaterial structure to the MRE isolator, the vibration attenuation capacity of the MRE isolator can be greatly improved. Nevertheless, the frequency range of the vibration bandgap is hard to be lowered and the frequencies of unwanted vibrations are mostly not very high, which limits the practical applications of acoustic metamaterial MRE isolator in engineering fields. On this basis, a novel MRE isolator designed with acoustic metamaterial structure and installed with inerters was designed and prototyped. The inerters can provide large equivalent mass with small own mass, which can lower the frequency range of the vibration bandgap effectively and maintain the structure stability of the MRE isolator in the meanwhile. Then, by controlling the stiffness of the MRE layers, the stop frequency of the vibration bandgap can be increased, which can further broaden the vibration bandgap to improve the vibration isolation capacity. The influence of the inerters is researched and verified theoretically and experimentally. Then, isotropy and anisotropy MRE layers with different stiffness are tested to further optimise the performance the MRE isolator. The evaluation experiments were conducted and results demonstrate that the new MRE isolator possesses low frequency vibration bandgaps and can provide great vibration isolation performance.

MRE isolator,inerter,low frequency bandgap,acoustic metamaterial