Metamaterial shaft with a low Poisson’s ratio lattice structure for torsional vibration isolation

To suppress the torsional vibration of shafts, a metamaterial structure made up of the lattice structure with a low Poisson’s ratio is presented in this paper. Firstly, to improve the efficiency, the homogeneous model is established to replace the lattice structure. Its homogenized properties are estimated using the asymptotic homogenization (AH) method. Subsequently, through the Bragg scattering (BS) mechanism and the transfer matrix method (TMM), a parametric analysis is performed to evaluate the influence of the structural parameters of the metamaterial shaft on the band-gap distribution. Furthermore, using the data-driven optimization method, the band-gap distribution of the metamaterial shaft is optimized so as to attenuate the torsional vibration of the electric drive system of the hybrid electric vehicle (HEV). The optimization results show that not only does the range of band gap for the optimized metamaterial shaft satisfy the optimization target of 1200–4000 Hz, but also the band-gap width increases significantly. Finally, the optimized metamaterial shaft is fabricated by additive manufacturing technique, and its vibration isolation performance is verified experimentally.