Digitally coded T-slot-connected gradient metastructures for morphing wings with programmable mechanical properties

Most metastructures retain fixed properties after fabrication, limiting adaptability. This work develops a T-slot–connected gradient metastructure (TCGMM) whose mechanical response is programmed by assembly using a two-dimensional layout matrix with entries {–1,0,1} to specify the orientation (±1), presence (0), and position of female platelets. Four series (A, B, C, D) of TCGMMs are designed and evaluated in three-point bending and torsion via finite element analysis (FEA) and experiments (EXP). Results show that both the equivalent bending modulus and torsional stiffness can be tuned by the assembly pattern. In torsion, symmetric layouts yield equivalent torque–rotation responses; positioning the platelet near mid-height maximizes torsional resistance. In bending, multi-column layouts of female platelets (Series C) achieve a higher mean equivalent modulus than single-column layouts (Series B) by ≈39 % (EXP), demonstrating the benefit of increasing lateral constraint and load-transfer efficiency. The results of FEA and EXP are in agreement, which proves the accuracy of the mechanical performance analysis. The matrix-based parametric strategy enables rapid, reconfigurable design of TCGMMs and suggests strong potential for multi-degree-of-freedom morphing wings and related aerospace structures.