PLAN 84: Article
Introducing the Self-Assembly Lab
Imagine a world in which large-scale man-made structures could assemble themselves, reconfigure themselves or even change their material properties.
Architecture alum and lecturer Skylar Tibbits (SM’10, Design Computation; SM’10, Computer Science) is working on bringing that world about by developing ‘smart’ components that translate natural molecular processes and computational processes into self-assembly technologies for the built environment.
Self-Assembly is a process by which disordered parts build an ordered structure entirely on their own, a process Tibbits enables by fabricating objects that can respond to various energy sources to change themselves over time. To formalize this line of inquiry, he recently established the Self-Assembly Lab at SA+P.
The increasing complexity of our built environment – buildings, machines, computers and almost everything else – is creating exponential growth in the intricacy of construction. A skyscraper involves up to a million parts and takes more than two years to assemble; a spaceship involves 2.5 million parts and takes five years to assemble.
But in the world of natural systems, there are proteins with two million types that can reconfigure in 10,000 nanoseconds. And DNA with three billion base pairs that can replicate in roughly an hour. All with far more efficiency than anything we can build, and with virtually no mistakes.
Tibbits’ aim is to render that sort of self-assembly into the built environment, a challenge he has determined requires four key factors:
• Decoding the complexity of the intended structure into simple sequences
– basically the blueprints for how the structure will work
• Programming component parts that can read those sequences
and reconfigure themselves accordingly
• Deploying energy to activate the process
• Incorporating redundancy and error correction
His exploration of those possibilities have taken a number of forms so far. He collaborated with Neil Gershenfeld's Milli-biology team at SA+P’s Center for Bits and Atoms to develop the Macrobot and Decibot – two jointed reconfigurable robotic chains, 8’ and 12’ long, each joint of which contains hard-wired communication to its neighbors and sensors that can detect its position and direction of rotation.
To transform the chain from a one-dimensional string into two- or three-dimensional shapes, Tibbits describes the shape he wants to create in terms of a sequence of angles, then transmits that data through the string; as each unit receives the coded message, it rotates itself as instructed then passes the sequence on to its neighbor.
He then developed a series of self-folding toys that have the instructions for assembly coded directly into each link, so the structures themselves contain the blueprints of what he wants to build. When the encoded chains are randomly shaken a non-random structure emerges, demonstrating a completely passive version of the reconfigurable robotic strands.
Working with Arthur Olson, director of the Molecular Graphics Laboratory at the Scripps Research Institute, Tibbits also designed and constructed the Self-Assembly Line, an interactive installation that demonstrates molecular self-assembly at an architectural scale, making explicit dynamic phenomena usually hidden from common experience.
Then, working again with Olson, he created the Bio-Molecular Self-Assembly Project – a collection of little coded pieces that, when shaken in a beaker, assemble themselves into a 3-D model of a polio virus, the pieces held together through their shapes and magnetic properties. During the shaking, some of the bonds between the pieces break while others bond more strongly until the weeding out of weak bonds results in the coded virus geometry finally stabilized.
Most recently, he has developed something called 4D Printing by using a new material that transforms itself in water. In collaboration with Stratasys, one of the industry leaders in 3-D printing, he designed and printed a string of pieces that, when dunked in water, wiggles its way into spelling out ‘MIT’ or into a 3D cube (sort of like those Magic Gro capsules that turn tiny sponges into dinosaurs). Next up, he aims to devise a 50-foot strand of coded material that will transform itself into an 8-inch-square of intricate space-filling curves when submerged in water.
The implications for this line of research are truly radical. What if this new material from Stratasys could be used to make water pipes that could expand or contract based on their contact with water, getting bigger to accommodate the runoff from a hurricane then contracting when the storm is over? What if pipes could bend – but not break – during an earthquake?
What if an earthquake were the energy source, the shaking ground causing a structure to adapt with more flexibility or rigidity based on dynamic conditions? What if self-assembling structures could be shipped to disaster areas for creating emergency housing or refugee camps?
Or more importantly, as one wag has suggested, what if your Ikea desk could be made to assemble itself? ‘Dare,’ says Tibbits, ‘to think about what’s possible’.
To learn more about self-assembly research, contact Skylar Tibbits at sjet@MIT.EDU.