The Milli-Motein: A self-folding chain of programmable matter with a one centimeter module pitch

The Milli-Motein (Millimeter-Scale Motorized Protein) is ca chain of programmable matter with a 1 cm pitch. It can fold itself into digitized approximations of arbitrary three-dimensional shapes. The small size of the Milli-Motein segments is enabled by the use of our new electropermanent wobble stepper motors, described in this paper, and by a highly integrated electronic and mechanical design. The chain is an interlocked series of connected motor rotors and stators, wrapped with a continuous flex circuit to provide communications, control, and power transmission capabilities. The Milli-Motein uses off-the-shelf electronic components and fasteners, and custom parts fabricated by conventional and electric discharge machining, assembled with screws, glue, and solder using tweezers under a microscope. We perform shape reconfiguration experiments using a four-segment Milli-Motein. It can switch from a straight line to a prescribed shape in 5 seconds, consuming 2.6 W power during reconfiguration. It can hold its shape indefinitely without power. During reconfiguration, a segment can lift the weight of one but not two segments as a horizontal cantilever.
United States. Defense Advanced Research Projects Agency. Programmable Matter Program
United States. Defense Advanced Research Projects Agency. Maximum Mobility and Manipulation (M3) Program
United States. Army Research Office (Grant W911NF-08-1-0254)
United States. Army Research Office (Grant W911NF-11-1-0096)
Massachusetts Institute of Technology. Center for Bits and Atoms