Multinozzle printer for creating complex objects, fast

MM3D printing can seamlessly print objects out of inks with varying degrees of stiffness, such as this collapsible origami-inspired sheet. The “joints” are printed from a softer, more flexible material than the “panels,” so the whole structure can be repeatedly folded and unfolded. Credit: Lori K. Sanders

3D printers are revolutionizing manufacturing by allowing users to create any physical shape they can imagine on-demand. However, most extrusion-based printers available commercially are only able to build objects from a single nozzle at a time. Those that can deposit multiple inks are even slower due to the additional time required to switch between materials.

Multimaterial multinozzle 3D printing (MM3D), a new technique created by researchers at the Wyss Institute and Harvard’s John A. Paulson School of Engineering and Applied Sciences (SEAS), has finally brought extrusion-based 3D printing-at-scale into the realm of possibility thanks to its unique system of high-speed pressure valves that enable rapid, continuous, and seamless switching between up to eight different printing materials up to 50 times per second, about as fast as a hummingbird beats its wings.
Voxelated Soft Matter via Multimaterial, Multinozzle 3D PrintingPlay
Multimaterial multinozzle 3D (MM3D) printing can switch between up to eight different inks 50 times per second, allowing the creation of complex, high-quality 3D objects in a fraction of the time currently required by other extrusion-based printing methods. Credit: Wyss Institute at Harvard University

The key to MM3D printing’s speedy ink-switching is a series of Y-shaped junctions inside the printhead where multiple ink channels come together at a single output nozzle. The shape of the nozzle, printing pressure, and ink viscosity are all precisely calculated and tuned to prevent backflow and ink mixing during the printing process, thus enabling the precise printing of a 3D multimaterial part. The lengths of the ink channels can also be adjusted to account for materials that have different viscosities and yield stresses, and thus flow more quickly or slowly than other inks.

Using our broad palette of functional, structural, and biological inks, disparate materials can now be seamlessly integrated into 3D-printed objects on-demand.

Jennifer A. Lewis
MM3D printing has potential applications in many settings, including:

Rapid prototyping and iteration
Scalable and massively parallelized 3D printing
Large-scale and rapid biofabrication
3D printed soft robotics and lightweight composite materials
3D printed electronics and sensors

The Wyss Institute is seeking industrial and research partners to assist with commercialization efforts of this technology.

ww.wyss.harvard.edu