Inverse design of self-rotating dual-platform biomimetic mechanical metamaterials via additive manufacturing

Abstract

To enhance the mechanical properties of auxetic structures, numerous designs have been developed and analyzed. However, many existing methodologies lack comprehensive principles to effectively guide other structural design processes. In this study, a novel buckling-based biological windmill auxetic structure is introduced. First, a comparative analysis of the mechanical properties across different biological windmill structures was conducted. Then, a buckling design approach was employed to enhance the deformation characteristics and stress-strain behavior of windmill auxetic structures. Finally, an inverse design process was implemented to identify the optimal target structural parameters by Bayesian-optimized Gaussian process regression models. The results indicate that the “X” crossbar design method achieves greater specific energy absorption (SEA), smoother platform stress, making it particularly suitable for shock energy absorption applications. Additionally, the re-entrant structure design method demonstrates superior SEA, and outstanding crushing energy absorption (CFE). The buckling design of the support rod not only provides exceptional SEA but also exhibits favorable crushing modes. This study advances the concept of rotating auxetic structures, by investigating their crushing behavior and energy absorption characteristics, offering valuable insights for the further development of auxetic structural design methodologies.