Aerospace equipment is evolving towards greater mobility

extended range

and increased load-bearing capacity

which puts forward higher requirements for the lightweight design of structures. As the new type of low-density lightweight structure

lattice structures have excellent mechanical properties such as high specific strength and specific stiffness

showing great prospects in the field of lightweight design. However

the lattice structures generated by traditional array method is not being able to avoid damage to integrity of the lattice structures and stress concentration due to the cropping operation

particularly in modeling structures with complex shapes. This study proposes a unified mathematical characterization and conformal design method for lattice structures based on implicit modeling. The design of functional gradient conformal lattice structures is achieved through the size-optimization technique. Design experiments of fairing and skin demonstrated that gradient design of conformal lattice structures enhanced structural stiffness. Stiffness of the optimized fairing and skin increased by 23.0% and 60.5%

respectively

which verifies potential of the proposed method in application of lightweight design of aircraft structures.