Sitting on a table in Skylar Tibbits ’s lab, at MIT’s new Center for International Design , is a 200-gallon-fish tank--it's large enough to hold one of Damien Hirst’s pickled sharks . If Tibbits’s experiment goes according to plan, within the next few weeks, it will be the scene of a sort of fractal monster movie. A 50-foot-long strand of coded mystery material will be dumped into the water-filled tank, and transform--without benefit of human hands!--into a sweet little 8-inch square Hilbert curve .
How long will it take? Nobody knows.
“It will probably depend on how hot the water is, or if I add a little salt,” jokes Tibbits, the 28-year-old wunderkind architect-designer-computer scientist behind what may be the next wave in manufacturing: 4-D printing.
The concept of self-assembly isn’t new: It has been used at nanoscale for years. But Tibbits is an architect. Sure, folding proteins  is cool, he thought, but imagine if you could use this technology to build bridges and buildings--or even just pipes? Now, that would be a totally different dimension of cool. "I thought, 'If you can’t see it, why do it?'" he says. “I wanted to go larger scale.”
On the wall is a large aluminum and polyethylene structure called a Voltadom , bent into curves that mimic a vaulted ceiling. Along the edge of each piece is a series of tiny bolts, holding the whole thing together. It’s a tiny section of a larger, 30-foot long, artwork that Tibbits constructed for MIT’s 150th anniversary  in 2011. The structure required somewhere north of 5,000 bolts. It took Tibbits and his team of worker bees nearly a month to assemble the object the Olde School way, that is, piece by piece, by hand.
Sometime during that long, tedious project, Tibbits experienced what any manual laborer invariably thinks: There must be a better way.
But Tibbits is no ordinary grunt. His bio extends from being one of Zaha Hadid ’s hive of young architectural renegades to being the co-teacher of the architectural section of MIT professor Neil Gershenfeld ’s popular “How to Make (Almost) Anything ” class. So he was in a unique position to figure out how to make something make itself.
After meeting molecular biologist Arthur Olson, Tibbits began experimenting with 3-D printing and embedded magnets, designing pieces that would self-assemble if you added energy--shake a beaker full of little pieces and the parts inside assemble themselves into a 3-D model of a polio virus. The results were impressive, but still pretty labor-intensive.
Then, a few months ago, Tibbits mentioned his frustration to some of the folks at Stratasys, one of the industry leaders in 3-D printing . Fortuitously, they had just developed a breakthrough new material  that transforms in water, they said. Would he like to try it?
Now, he could print his structure on a 3-D printer, submerse it in a tub, and it would expand. If it was programmed correctly, it would self-assemble into a pre-determined shape while he watched.
Tibbits was psyched. He began tinkering in his shop. Using the new material, he designed and printed a long strand of pieces, using Autodesk’s Cyborg software  then dunked it in a tub of hot water. Before long, the strand had wiggled its way into spelling out the initials of his alma mater, “MIT.” 
Then he turned a strand into the first angles of a Hilbert curve. On the second iteration, he got it to be a bit more complicated. Soon, he hopes, he can code the algorithm necessary to get the whole thing--a 3-D labyrinth that grows, on its own, into a precise and complex object.
If Tibbits succeeds, he says, the implications are vast. Imagine if this technology could be used to construct pipes  that could expand or contract based on their contact with water. They might get bigger to accommodate the runoff from a hurricane, then contract when the emergency is over. Imagine pipes that could bend--but not break--during an earthquake.
Imagine being able to ship parts for structures to countries where unskilled laborers are the only help available, so they can assemble themselves. Imagine how this might work in the case of disaster housing or refugee camps. Transformers without Borders!
Imagine if that desk you bought from Ikea could assemble itself, while you kicked back and watched the game.
In Tibbits’s mind, the applications are endless. “This allows us to give materials a life,” he says.
In the future, he hopes to move beyond water to other energy triggers: light, heat, even sound. And he's attempting to 4-D print two-dimensional surfaces that self-fold like origami, as well as 3-D shapes that can transform from one object into another.
"I think we are just scratching the surface of what's possible in the future with 4-D printing and the capability to have physical objects transform in precise and designed way," he says.