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Morphing origami has numerous potential engineering applications owing to its intrinsic morphing features from 2D planes to 3D surfaces. However, the current 1D hinge deformation‐driven transformation of foldable origami with rigid or slightly deformable panels cannot achieve a 3D complex and large curvilinear morphing. Moreover, most active origami structures use thin hinges with soft materials on their creases, thus resulting in a lower load capability. This study proposes a novel origami morphing method demonstrating large free‐form surface morphing, such as Euclidean to non‐Euclidean surface morphing with shape‐locking. Tensorial anisotropic stress in origami panels is embedded during the extrusion‐based 3D printing of shape memory polymers. The extrusion‐based 3D printing of isotropic SMPs can produce tensorial anisotropic stress in origami panels during fabrication, which can realize significant non‐Euclidean surface morphing with multiple deformation modes. The connecting topology of the origami unit cells influences the global morphing behavior owing to the interaction of the deformation of adjacent panels. Non‐Euclidean morphing integrated with 4D printing can provide multimodal shape locking at material and structural levels.

Abstract Multi‐stable structures and metamaterials with more than two stable states are widely applied in diversified engineering applications. Non‐rigid foldable origami patterns have provided an effective way of designing multi‐stable structures. But most of them have only two stable states and therefore require a combination of many units to achieve multi‐stability. Here, a series of extensible origami structures are proposed with generic multi‐stability based on non‐rigid wrapping origami. Through a kinematic analysis and experiments, it is demonstrate that a sequential folding among different layers of the structures is created to generate a continuous rigid origami range and several discrete rigid origami states, which consequently leads to the multi‐stability of the extensible origami structures. Moreover, the effects of design parameters on the mechanical properties of the structures are investigated by numerical simulation, enabling properties programmability upon specific needs. This study thus paves a new pathway for the development of novel multi‐stable origami structures.

Origami and kirigami inspired foldcores have recently seen a surge in research and engineering applications mainly due to their open channel configuration to avoid moisture accumulation and diversification of design parameters to meet customized requirements. In this paper, a new kirigami-inspired pyramid foldcore was proposed, and the performance of the corresponding sandwich structure subjected to quasi-static out-of-plane compression and shear, respectively, were studied experimentally, numerically, and analytically. The deformation mechanism of the new sandwich in each loading scenario was revealed, and the effects of geometric parameters were obtained through parametric analysis. Moreover, a theoretical model was established to estimate the average shear stress of the sandwich. In comparison with the commonly adopted square honeycomb, Miura-ori, and eggbox sandwiches, the average compressive stress of the new sandwich was respectively increased by 73%, 342%, and 130%. Upon shear loading, the average shear stress of the new sandwich outperformed the Miura-ori by 34%, and was comparable with that of the square honeycomb by a difference of 11%. To summarize, the new foldcore shows great promise in the design of high-performance sandwich structures.