Wood-Based Oriented Object Deposition for Programmable Mechanical and 3D Fluidic Control.

The aligned fibrous architecture and intrinsic porosity of natural wood offer unique opportunities for constructing mechanically anisotropic and capillary-active structures. However, existing additive manufacturing techniques face challenges in preserving these structural characteristics, which limits the extent to which they can be leveraged in complex functional architectures. Here, we present Wood-based Oriented Object Deposition (WOOD), a 3D printing approach that integrates delignified wood sheets and digital light processing (DLP) to fabricate structures with preserved anisotropy and porosity. Sliced wood layers are impregnated with photocurable monomer, aligned, and selectively photopolymerized, enabling directional control of mechanical and fluidic properties. We further establish processing criteria for hybridizing delignified wood with photocurable monomer, ensuring sufficient light transmission, deep curing, and structural fidelity. Densification improves printing resolution by allowing finer layer stacking and reducing surface artifacts such as stair-stepping. By aligning fiber orientation across layers, we achieve programmable deformation for origami-inspired architectures with integrated flexibility and rigidity. Additionally, vertically laminated structures support 3D fluidic control, enabling pressure-actuated flow switching and spatially resolved pH sensing. WOOD offers a scalable and sustainable platform that unites the structural advantages of natural wood with the precision of additive manufacturing, unlocking possibilities in bioinspired materials, microfluidic devices, and multifunctional composites.