US Patent 11760003 Systems and methods for reinforcing multi-layer structures

The present disclosure relates to methods and systems for 3D printing. In one example, a 3D multi-layer structure is printed with a cavity distributed over multiple layers of a first filamentary material and shaped as a double-headed rivet. Further, the cavity is filled with a second filamentary material in a vertical direction to form a filament-based rivet, the vertical direction perpendicular to the plane of the multiple layers.