3D printing is unique to other methods of manufacturing in that it is more capable of producing incredibly intricate parts with little difficulty at all. Designers around the world are beginning to incorporate these unique qualities with previously impractical design techniques. The Hasso-Plattner-Institute has recently published a technique perfectly suited for 3D printing called Metamaterial Mechanisms that can adjust the bend of the item using a very precise placement of what they call shearing cells.
The basic principal behind their manufacturing approach is summed up nicely, as seen in the below video, by stating they “don’t consider metamaterials as materials, but as machines." These 3D printed geometric forms are designed to flex and move in a way that only assembled moving part structures could previously have functioned. The project report further notes that “our objects thereby implement devices that transform input forces and movement into a desired set of output forces and movement—also known as mechanisms.”
As already pointed out, the geometric pattern that make everything possible is the shearing cell. It is a specialized type of cell that is capable of folding over (or “shearing”) in a controlled, multidirectional movement. But in the end, to me, the most exciting element behind all of this research comes in the form of the metamaterial editor that allows the easy and custom assembly for 3D printing.
The editor allows the designer to follow a basic user interface, not unlike beginner tools like tinkercad or even Minecraft. You can very easily build cubes at varying stiffnesses while adding unique mechanical functionality to the item being produced.
And if you are wondering how on earth this is practical, it might be worth noting that they’ve been able to manufacturer simple pliers, drawing tools and even a jansen walker without requiring any assembly. The research paper itself suggests low-cost, flexible material NinjaFlex was used for their parts.
The paper also illustrates, in great detail, the want of shift toward their mechanical metamaterial approach over the current multi-material 3D printing technologies that can already produce mechanical parts in one run. They claim that multi-material printers are complex objects, hard to recycle and are wrought with the mechanical limitations common in traditional materials.
Of course, there is a lot to worry about when being introduced to the idea of a flimsy one-piece locking mechanism that would likely snap without little effort. But the way I see it, this is all still in the proof of concept stage. If mechanical properties and material sciences continue to merge, thanks largely to 3D printing, I’m all for it.
