https://www.newscientist.com/article/2171508-watch-a-3d-printed-magnetic-critter-fold-and-move-all-by-itself/ > They modified the nozzle of a 3D printer by surrounding it with coils of wire that act as an electromagnet. When the rubber is extruded, the microparticles become magnetically aligned along the direction of the magnetic field from the wire. The team could also change … > To continue reading this premium article, subscribe for unlimited access.