Jamming, Locking, and Multistability in Polycatenated Architected Materials

Topological complexity in materials offers a rich foundation for designing systems with adaptive mechanical properties. Polycatenated architected materials (PAMs)—comprising interlocked rings or cage-like particles forming three-dimensional networks—have recently emerged as a novel class of matter, exhibiting unique mechanical behaviors. These materials bridge the gap between discrete granular assemblies and continuous architected materials, while displaying a distinct "solid-and-fluid" duality, making them promising candidates for applications requiring tunable stiffness and energy dissipation. In this presentation, we extend the design space of PAMs beyond simple particle geometries by employing computational design techniques to engineer the topology and geometry of the constituent particles. We demonstrate how the introduction of polyknotted structures and lock-and-key contact interfaces within PAMs enables programmable jamming, locking, and multistability. This approach allows for easy tuning and switching of mechanical properties, such as tensile and bending stiffness, through simple mechanical inputs. From a fundamental perspective, we explore novel contact mechanics phenomena arising from topological entanglements, self-interactions, and interactions involving complex geometrical objects. These insights contribute to a deeper understanding of how topology influences material behavior at the macroscopic scale. From an applied standpoint, the ability to control mechanical properties through topological design opens new avenues for developing advanced materials in robotics, protective equipment, and adaptive systems, pushing the boundaries of material science and engineering.