Shape Reconfiguration via Geometric Constraint in Mechanisms Incorporating Stimuli‐Responsive Twisted Yarns

ABSTRACT This study explores reconfigurable shape permanence enabled by the geometric constraint of a material system incorporating stimuli‐responsive twisted liquid crystalline elastomer (LCE) yarns. The geometric constraint is introduced via subtractive manufacturing, creating multiple hole‐and‐pin mechanisms, where each ‘pin’ integrates shape‐changing elements. Exposure to stimuli enables remote and spatially selective control over structural reconfiguration, ensuring the system maintains its geometric constraint while allowing controlled transformation. To illustrate this concept, a model system with integrated latch mechanisms demonstrates both shape permanence and controlled reconfiguration through sequential latch releases. The system leverages the stimuli‐responsive behavior of twisted LCE yarn architectures, which enhance actuation efficiency and lower activation temperatures beyond what can be achieved through materials chemistry alone. In this way, the study highlights the convergence of stimuli‐responsive materials, advanced materials processing, and geometric constraint, enabling a unique combination of shape permanence and shape transformation. This ability to retain permanent shapes while enabling localized reconfiguration has broad implications for applications in medical devices, aerospace, adaptive textiles, and consumer products.