Design and Optimization of Bird-Bone-Like Aircraft Wing Structures

Increasing the efficiency of load-bearing structural components is an important challenge in engineering design. Architected lattice structures that consist of repeating arrangements of porous unit cells exhibit unique mechanical properties and present an opportunity to address this challenge. In this research, we utilize strut-based lattice structures made up of linear elements, or struts, that are connected at nodes for designing the internal structure of an aircraft wing subjected to aerodynamic loading. Tetrahedral unit cells are used as building blocks of the internal structure due to their high strength-to-weight ratio and stability. We define the distributions of unit cell size and radius of the struts as two sets of optimization variables over the design domain. The distribution of material within the structure is then optimized using an evolutionary algorithm to minimize the mass and maximize the stiffness of the wing while avoiding global buckling of the structure. Several combinations of weighting factors are assigned to the two competing optimization objectives to obtain the overall optimal solution considering the importance of each objective for specific design problems. This study employs finite element modeling to evaluate the performance of the lattice structure. The results demonstrate remarkable improvements in the overall performance and efficiency of the wing structure compared to conventional wings.