3D arc-shaped structure design of compression-twist coupling metamaterial

Compression-twist coupling (CTC) metamaterials are special mechanical metamaterials that convert axial force into circumferential force. Based on the dislocated re-entrant structure, a novel structure with line-shaped polyline rods is proposed to achieve the CTC effect. To reduce the stress concentration, a corresponding arc-shaped CTC structure is further designed, which is the focus structure of our study. The influence of the geometrical parameters of the arc-shaped structures on the CTC effect is explored through energy-based theoretical analysis, finite element simulation, and validation experiments. Finally, the CTC effects of extended single-side arc-shaped and multi-arc design structures are discussed. Compared with previous designs, the novel structure proposed in this work enhances the design flexibility and achieves a significant CTC effect, which can serve as a reference for the design of new CTC metamaterials.