Imagine a smart aqueduct that changes shape and increases its capacity in relation to its surroundings. To repair it, there is no need to take the road apart: the structure simply adapts itself to external forces. It is not science fiction, and it is all explained to us by Skylar Tibbits, an artist and architect at MIT. During his TED Talk he demonstrated how “self-assembly” represents the new frontier of 4D printing.
As one might imagine, the fourth dimension that Tibbits refers to is time. Linear or flat structures can be engineered in such a way that certain forces trigger a process of self-assembly. In practice, a slight movement causes a strand to bend in on itself and assume, of its own accord, a three-dimensional form.
An example to help you understand what we are talking about is the project that Tibbits has developed together with Autodesk. The most curious fact of all is that their source of inspiration is none other than biology. Self-assembly is a key characteristic that enables proteins to assume very precise 3D forms. Even the smallest of errors can cost dearly when a cell has to be made to perform as best as possible.
The point is that the characteristics that enable proteins to self-assemble can be replicated on a large scale even with artificial materials. Tibbits is experimenting with this function for 3D printers in partnership with Statasys. The idea is to print objects made of various materials which, when ready, can assume predefined three-dimensional forms.
It is all about identifying the most effective characteristics and types of geometrical interaction: once the 4D material has been tested on the computer, it can be printed. Of course, it is far from easy to do, and you might find that a little knowledge of bio-physics does no harm. Already available for those who wish to experiment with nanotechnological design is the free open source software cadnano.
The fields of application of this type of technology are practically infinite. These range from furnishings to engineering and environmental design. Above all, 4D objects could help us with construction sites in hostile environments. Who knows, maybe one day Tibbits’ smart strands will rank alongside the D-Shape by Enrico Dini, the giant 3D printer for making lunar modules with sand.