Structural Mechanics of Bionic Panel Inspired by Ladybird Elytra Under Tensile and Flexural Loads

ABSTRACT To enhance tensile and flexural properties, a novel bionic composite panel was developed. Unlike existing bionic composites with continuous fiber orientations, this study proposes a novel approach inspired by the discontinuous fiber architecture observed in ladybird elytra. The panel consists of a 12‐layer carbon fiber/resin laminate with a symmetric stacking sequence [0/45/−45/30/0/75] _s . Tensile and three‐point bending tests were conducted to evaluate mechanical performance. A finite element model incorporating 3D Hashin and Yeh failure criteria was developed to predict damage initiation and delamination. Then the stiffness matrices and elastic constants were calculated and compared. Compared to the conventional panel, the bionic panel exhibited increases of 11.69% in elastic modulus, 126.06 MPa in tensile strength, 21.26% in fracture load, and 42.33 MPa in flexural strength. These improvements are attributed to the bionic ply sequence enhancing stress distribution and crack deflection. Further optimization via the Non‐dominated Sorting Genetic Algorithm (NSGA‐II) yielded an optimal ply stacking sequence [0/30/−45/0/45/75] _s , achieving a 40.32% increase in flexural strength compared to the bionic panel before optimization. These findings demonstrate an effective approach for lightweight structural optimization, with potential applications in aerospace and automotive engineering.