Researchers at MIT's Distributed Robotics Laboratory are working on the ultimate building blocks of the future: grains of "smart sand" that can self-assemble and replicate any object submerged in a heap of the sand. The tiny robots communicate to form the object, which can be replicated at any scale.
MIT explains the process like this:
"Unlike many other approaches to reconfigurable robots, smart sand uses a subtractive method, akin to stone carving, rather than an additive method, akin to snapping LEGO blocks together. A heap of smart sand would be analogous to the rough block of stone that a sculptor begins with. The individual grains would pass messages back and forth and selectively attach to each other to form a three-dimensional object; the grains not necessary to build that object would simply fall away. When the object had served its purpose, it would be returned to the heap. Its constituent grains would detach from each other, becoming free to participate in the formation of a new shape."
This technology could be used to cut down on the waste in our lives. If an object has a broken part, you could duct tape that part back together, put it in the sand and, voilà, it's fixed. Alternatively, once you were done using an object created in the sand you could simply tell it to disassemble and then have it assemble into something else.
Right now the researchers are working with larger 10 millimeter cubes they're calling smart pebbles to test out the computer algorithms behind the technology. The pebbles are able to self-assemble using "electropermanent magnets," whose magnetism can be switched on and off with jolts of electricity, allowing them to come together, communicate and share energy and then also fall apart quickly. Each pebble contains a tiny microprocessor capable of storing 32 kilobytes of program code.
Here's a video demonstrating the technology:
The real challenge will be scaling down the technology to the size of tiny grains of sand -- especially difficult will be outfitting the grains with enough computational power to run the algorithms -- but it's not impossible. Robert Wood, an associate professor of electrical engineering at Harvard University said the core principles are already working in the pebbles.
“They have the ability to latch onto their neighbors; they have the ability to talk to their neighbors; they have the ability to do some computation. Those are all things that are certainly feasible to think about doing in smaller packages."