3D anisotropic rotating re-entrant honeycomb with bidirectionally programmable multi-stage plateau stresses

Three-dimensional (3D) honeycombs overcome intrinsic limitations of two-dimensional lattices by exploiting spatial topology, thereby enabling higher energy absorption, tunable anisotropy, improved out-of-plane stability, and better integration in engineering systems. We design a 3D anisotropic rotating re-entrant honeycomb (ARRH) and characterize its response via quasi-static compression tests and finite-element simulations. ARRH exhibits pronounced programmability and anisotropy: under Y-direction compression it develops three plateau stages with negative v_xy and near-zero v_zy values; under Z-direction compression it shows two plateau stages with positive v_xz and v_yz values. Parametric studies reveal orthogonal “knobs'’ for tailoring performance: the wall thickness programs the stress values of three plateaus, the rotation angle programs the strain range of the first plateau stage, and the re-entrant angle programs that of the second plateau stage under Y-direction; under Z-direction, the wall thickness programs the stress values of two plateaus, and the re-entrant angle controls the first-plateau range. These results establish ARRH as a practical architecture for multi-stage, anisotropic, and programmable energy-absorbing metamaterials suitable for adaptive protection and morphing structures.