Shape-Programmed Self-Assembly of Bead Structures

This paper demonstrates the potential of a robust, low-cost approach to programmable matter using beads and string to achieve complex shapes with novel self-organizing and deformational properties. The method is inspired by the observation that beads forced together along a string will become constrained until they spontaneously rigidify. This behavior is easily observed using any household string and flat-faced beads and recalls the mechanism behind classic crafts such as push puppets. However, specific examples of architectural applications are lacking. We analyze how this phenomenon occurs through static force analyses, physical tests, and simulation, using a rigid body physics engine to validate digital prototypes. We develop a method of designing custom bead geometries able to be produced via generic 3D-printing technology, as well as a computational path-planning toolkit for designing ways of threading beads together. We demonstrate how these custom bead geometries and threading paths influence the acquired structure and its assembly. Finally, we propose a means of scaling up this phenomenon, suggesting potential applications in deployable architecture, mortarless assembly of nonfunicular masonry, and responsive architectural systems.