Effect of Graphene Origami Metamaterials on Dynamic Performance of Shear-Deformable Elements as Taekwondo Sport Equipment under Temperature Changes

This study analytically examines the dynamic behavior of a shear-deformable plate representing a taekwondo sport element reinforced with graphene origami metamaterials (GOMMs) under thermal loading. A higher-order framework based on the simplified shear deformation theory is formulated through Hamilton’s principle to simultaneously capture mechanical and thermal effects without requiring a shear-correction factor. The effective material properties are determined using an enhanced rule of mixtures that incorporates the folding degree, spatial distribution, and geometric configuration of the GOMMs. The main novelty of this work lies in establishing the first coupled thermo-mechanical analytical model capable of predicting the vibrational response of GOMM-reinforced sport structures. The parametric investigation shows that the metamaterial distribution, folding geometry, and intrinsic length-to-thickness ratio strongly influence the stiffness and natural frequencies. The results further indicate that increasing the GOMM content significantly enhances dynamic stability and reduces thermal softening, with the X-type folding pattern providing the highest stiffness retention at elevated temperatures. Overall, the proposed analytical framework offers valuable insight for designing lightweight, impact-resistant, and thermally robust sport equipment and can be extended to a wide range of composite systems employing architected metamaterials for multifunctional performance improvements.