Multi-objective optimization for inverse bandgap design in tensegrity metastructures

This study introduces an optimization-based inverse design framework for periodic tensegrity unit cells, enabling the formation of multiple bandgaps at targeted frequencies through the synergistic effects of Bragg scattering and local resonance. A general three-dimensional tensegrity formulation is developed and non-dimensionalized to reveal key governing parameters. Pass bands and bandgaps are determined using unit cell dispersion analysis based on Bloch’s theorem, with predictions verified against finite lattice frequency response functions. To navigate the complex tensegrity design space, a multi-objective optimization strategy is employed to tailor material, geometric, and resonator parameters toward desired bandgap targets under realistic physical constraints. Two case studies illustrate the trade-offs between competing bandgap objectives and demonstrate that optimal designs consistently incorporate local resonators. These results underscore the pivotal role of resonators in achieving multiple targeted bandgaps and establish inverse design as a powerful tool for engineering tensegrity metastructures.