Abstract: Design for light weight is very important in overall aircraft design because of the need for aircraft mobility and low energy consumption. In nature, after the evolution of hundreds of millions years, the organism obtains the optimal structure to adapt to the living environment based on the effect of gravity and environmental load. After an analysis of the load similarity between an aircraft reinforced frame and a dragonfly wing, some feature structures, which influence the mechanical proprieties of the dragonfly wing, are extracted for use in the design of the aircraft reinforced frame. Meanwhile, the finite element analysis (FEA) tool is used to verify the optimization effect. It is found that, compared with the conventional structure, bionic structures can increase specific stiffness by 2%-6% and specific strength by 1%-8%. The maximum stress decreases while the minimum stress increases, which indicates that the bionic structures result in more uniform stress distribution. Therefore, the study suggests that the bionic structures obtain optimal distribution of material and maximum structural efficiency.

Key words: dragonfly wing, reinforced frame, structural bionics, light weight structures, specific stiffness, specific strength, uniform stress