How would you like to have your very own shape-shifter? Perhaps a liquid metal T-1000 Terminator to help around the house. Or a universal tool kit that could reshape itself into any implement at the press of a button. For an astronaut in orbit, an army mechanic in remote terrain or even a homeowner trying to fix a furnace on a cold winter night, it could be just the thing.

Well, one day maybe. The traditional approach to building shape-shifting devices has been to use materials based on shape memory alloys, polymer sheets or nanoparticles. But these have proved difficult to control and have other limitations, so researchers have begun taking a different and less exotic tack.

Their approach is known as self-reconfigurable robotics, and it takes advantage of recent advances in robot hardware, communications and control algorithms. Last year a team of US researchers from different universities put together a blueprint for shape-shifting based on cell-like robotic “modules” that can rearrange themselves to create different shapes. They made their pitch to the Defense Advanced Research Projects Agency. As a result, DARPA set aside $4 million for a set of six-month studies to design modules that could be mass-produced for demonstrations. The agency is prepared to fund 18-month contracts to pursue the most promising designs.

Instead of trying to control individual molecules or create nanoparticle fluids that morph from puddles to silver-skinned cyborgs, DARPA programme manager Mitch Zakin is pursuing what he calls “programmable matter”. These are so-called “mesoscale” mini-machines, a millimetre to a centimetre in size, that can arrange themselves to form whatever shape is desired. Initially, Zakin expects the outcome to be devices the size of small Lego pieces, but as the technology improves the modules and the machines assembled from them should scale down further. Ultimately you could tell a sack of “smart sand” what to do, and the grains would assemble themselves into a hammer, a wrench or even a morphing robotic aircraft. “It’s making machines more like materials, and materials more like machines,” says Daniela Rus, a robotics researcher at the Massachusetts Institute of Technology.

Read more…