Abstract Vibration control at low frequencies remains a critical challenge in engineering structures. This study introduces eight novel hierarchical lattice metamaterials that integrate reentrant, chiral, and circular geometries within unit cells to achieve unprecedented bandgap properties. A multiobjective genetic algorithm was employed to optimize three key performance criteria: total bandgap width, individual bandgap width, and low-frequency attenuation. The optimized designs exhibited remarkable improvements, with up to 534% increase in cumulative bandgap coverage compared to non-optimized structures. Fabricated via laser cutting, the proposed metamaterials were experimentally validated through transmission measurements, which confirmed their superior vibration suppression. Results demonstrated attenuation of up to ~200 dB across targeted frequency ranges, effectively eliminating vibration transmission in the sub-1000 Hz domain that is traditionally difficult to address. The novelty of this work lies in the systematic geometric hybridization of lattice structures, the integration of optimization-based design, and the experimental confirmation of low-frequency bandgaps. The demonstrated manufacturability and outstanding vibration mitigation performance establish these hybrid reentrant-inspired metamaterials as a practical and scalable solution for structural vibration control. Their potential applications span aerospace, civil infrastructure, precision manufacturing, and other engineering fields where conventional approaches fail to provide effective low-frequency attenuation.
Jazi et al. (2025) studied this question.