Crashworthiness analysis and multiobjective optimization of bio-inspired sandwich structure under impact load

A novel bio-inspired sandwich structure with sinusoidal cores (hereinafter referred to as BS) was developed based on the dactyl club microstructure of Odontodactylus scyllarus (O. scyllarus), including two different configurations of the core section (abbreviated as BSS and BSD). The crashworthiness of BSS and BSD with different height-length ratios eta (the ratio between height A and length lambda of the sinusoidal core unit, and eta ranges from 0.4 to 1.6.) were comprehensively investigated under low-velocity impact condition, taking initial peak crush force (F-p), specific energy absorption (SEA) and crush force efficiency (CFE) as evaluation criteria. The crashworthiness between BSSs with lambda = 20 mm and BSSs with A = 20 mm under the same eta condition was discussed. Simulation results showed that the crashworthiness of BSSs with lambda = 20 mm is better than that of BSSs with A = 20 mm. The BSDs have superior crashworthiness when the difference between eta(1) and eta(2) is the smaller. The BSDs demonstrate better crashworthiness when eta(1) and eta(2) exceed 0.8 compared with other cases. A metamodel-based multiobjective optimization method based on a polynomial regression (PR) metamodel and a multiobjective particle optimization (MOPSO) algorithm were employed to optimize the dimensions of BSS and BSD under four designed cases, where the wall thickness t and eta were regarded as the design variables. The optimal solutions for the multiobjective optimization of BSS and BSD were obtained for different cases. The multiobjective optimization results showed that the BSS is advantageous in terms of the optimal criteria under Case-I and Case-II compared with BSD, whereas the differences between BSS and BSD under Case-III and Case-IV are insignificant. Further research pertaining to the crashworthiness of bio-inspired sandwich structures with multi-layer sinusoidal cores should be conducted.

Automated summary

A novel bio-inspired sandwich structure with sinusoidal cores based on the dactyl club microstructure of Odontodactylus scyllarus was developed and comprehensively investigated. The crashworthiness of different configurations and dimensions of the core section were optimized using a multiobjective optimization method. The study found that design dimensions and configurations significantly affect the crashworthiness of the sandwich structure.