Experimental verification and optimization research on the energy absorption abilities of beetle elytron plate crash boxes

To develop a new type of biomimetic sandwich plate crash box inspired by beetle elytra (referred to as the beetle elytron plate (BEP) crash box) with a better energy absorption capability, we conducted experimental verification and optimization research on two methods proposed in our previous studies: changing the amplitude (A) of the deformation leading line predicted by the finite element method and setting the trabeculae in the middle of the honeycomb walls. The following results were determined. (1) The method of increasing A to reduce the peak force of the BEP crash box is effective, whereas the latter method is invalid. (2) The latter method is invalid because the unit structure (the BEP crash box) is different from the multivariate structure (the BEP) used to determine the prediction due to the change of constraint condition on the trabeculae provided by the honeycomb walls. (3) An optimum A of 1.0 is proposed for BEP crash boxes with better energy absorption abilities and more stable successively laminated deformation. Specifically, the main peak force of the BEP crash box is approximately the same as that of the conventional one, while the structural energy absorption (SEA) and load uniformity (LU) of BEP crash boxes are at least 3 times and between only one-third and one-fourth those of conventional crash box, respectively, meaning that BEP crash boxes can be directly used to replace conventional one and to significantly improve security. Thus, these results provide an experimental basis for further research on BEP crash boxes.