The energy required to initiate self-assembly in the MIT/Stratasys project comes from interactions of the water molecules with the molecules of the water-expanding material, said Dikovksy. Other energy sources could include humidity, sound, heat, or vibration. But before that, the next step could be generating energy by removing water, which will make the structure contract instead of expand.
In an interview on the TED blog about his 2013 TED Talk, Tibbits says potential applications for the technology are space systems that expand and self-assemble in orbit, activated by changes in pressure, temperature, or light.
Self-assembly of artificial systems is not a new idea. It's being pursued at the nano-level, using carbon nanotubes and organic or engineered DNA, as well as various methods for modular, self-reconfigurable robots.
We've covered mechanical, self-assembling robots such as the Smart Pebbles robotic cubes built by a team in the Distributed Robotics Laboratory (DRL) of MIT's Computer Science and Artificial Intelligence Lab (CSAIL). At the nano-device level, we've reported on synthetic DNA strands programmed to self-assemble into 2D tiles, and more recently, into 3D bricks, by researchers at Harvard's Wyss Institute for Biologically Inspired Engineering.
Many of the developments in robotics are actually aimed at product manufacturing: The idea is to use robotic modules to make rapid prototypes, self-repairing systems, replacement parts for other systems, and self-reconfiguring systems like furniture that changes from a chair into a table. Adding expandable, programmable materials and 3D printing to this mix will give the development of this rapidly-changing field a big boost.
eafpres, thanks for the feedback. My April feature on self-assembly and self-reconfiguring robots will touch on several of these subjects. If you're interested in nanoscale self-assembly, I suggest you check out DNA origami and the Wyss Institute work on DNA 2D tiles and 3D bricks.
Thanks for sharing this. I watched the underwater cube, then I watched Skylar's TED talk as well. When you think about a system like this, it makes sense that 3D printing (or some form of 3D manufacturing) and self-assembly go together--things we want in the world are mainly 3D, so they are assembled out of 3D parts (the printer that prints out of stacked sheets notwithstanding--they are still 3D--they have thickness!).
It is interesting to think about gravity as the main source of energy (potential energy) and building structures. In a sense, this is already done on a large scale or certain types of retaining walls. You have 3D blocks that fit together, and gravity provides the force to keep them together. I have seen some blocks for walls that are very large--think a concrete lego brick the size of a bale of hay. Some I have seen have bumps on one side and dents on the other, so they stack and won't move horizontally, and gravity does the rest.
On a smaller scale, I wonder what could be done with structures that respond to other sources, such as thermal, and pH, or even blood chemistry, and how those could be used in the body.
HP revealed more of its 3D printing plans in a recent webinar. Senior vice president of inkjet and graphics solution business Stephen Nigro spoke about how the technology works and expanded on HP's vision of open collaboration to commercialize its Multi Jet Fusion 3D printing technology for end-production, and open collaboration on new materials. He also said HP will create software to help users decide when to use Multi Jet Fusion versus conventional subtractive manufacturing.
A lightweight electric urban concept car designed by several European companies weighs only 992 lb without its battery. It would have weighed 26.7 lb more if its windows were made of glass instead of the specially coated LEXAN polycarbonate resin from SABIC Innovative Plastics.
Skylar Tibbits' team in MIT's Self-Assembly Lab is now 4D printing self-assembling shapes made of programmable carbon composites and custom wood grain. The composites are being used in a sport car airfoil, and the wood grain is beautiful.
The NanoSteel Company has produced high-hardness ferrous metal matrix composite (MMC) parts using a new nanosteel powder in a one-step 3D-printing process. Parts are 99.9% dense, crack-free, and with wear resistance comparable to M2 tool steels.
Focus on Fundamentals consists of 45-minute on-line classes that cover a host of technologies. You learn without leaving the comfort of your desk. All classes are taught by subject-matter experts and all are archived. So if you can't attend live, attend at your convenience.