We 3D-print devices containing channels that trap floating objects using repulsive capillary forces 5, 6, then move these devices vertically in a water bath. Here we dynamically modulate these forces to move objects in programmable two-dimensional patterns. Once assembled, such structures are generally static.
Objects that deform a liquid interface are subject to capillary forces, which can be harnessed to assemble the objects 1, 2, 3, 4.
