Closed-loop direct ink extruder system with multi-part materials mixing

The field of additive manufacturing has expanded from single material-based 3D printing to multimaterial printed complex smart structures with intrinsic sensing capability. However, current multimaterial 3D printers allow printing of one material at a time, with limited ability of mixing multiple materials. Herein, we present the new 3D printer which eliminates the above shortcoming by merging the Fused Filament Fabrication and Direct Ink Write in one compact system. The developed printer expands the range of materials that can be printed and allows mixing and printing of multi-part materials with cost effective parts and increases the printing window of complex materials such as two-part rubbers. The experiments performed using various materials show the developed 3D printer having good control even at high printing speeds (up to 20 mm/s). The performance of the printer was evaluated extensively by varying different parameters such as nozzle diameter, pressure and printing speed. Finally, the capability of developed printer is demonstrated by autonomous printing of various 3D smart structures.