Bricks which are able to self-assemble into a 3D polygon are described in Scientific Reports this week. Using an algorithm to program self-assembly, the bricks were able to construct an object using agitation alone.

Assembly lines are currently used to build complex shapes and require information to build these shapes in the form of trained personnel or automatic assembly machines. However, self-assembly may offer an information-economical route to complex fabrication. While programmable self-assembly has been shown on the molecular to micrometre scales, no known algorithm can program macro-scale objects to self-assemble.

Ido Bachelet and colleagues created a series of 18 tetrahedral bricks which were able to self-assemble into a larger 3D cylinder. Each brick was imprinted with complementary topographic cues on their surface providing the rules for construction of the object, while attraction between the bricks was provided by embedded magnets. The bricks were then placed in a container and agitated leading to the assembly of the object with zero errors. The authors suggest that improved designs could lead to rapid fabrication of objects without the need for assembly lines.