Cross‐Scale Decoupling of Mechanics and Kinematics in Chiral Tensegrity Metamaterials

ABSTRACT Compression‐torsion metamaterials (CTMs) that break spatial inversion symmetry face persistent trade‐offs among large deformation capacity, intrinsic stiffness, and fatigue durability. Crucially, boundary rotation induced by axial compression complicates integration with rotationally constrained engineering interfaces. Here we introduce a chiral three‐rod tensegrity cell (CTTC) paradigm that addresses these conflicts through a cross‐scale dual‐decoupling strategy. First, mechanical decoupling at the unit‐cell scale separates macroscopic shape‐morphing from large local material strain: a heterogeneous rigid‐flexible architecture channels global compression into kinematic rod displacement and uniform elastic‐network stretching, achieving 97° torsion at Level 0 and only 4.87% peak‐force degradation over 10 000 cycles at Level 3. An integrated geometric interlocking reconfigurator further enables post‐fabrication programmability of stiffness and strain‐normalized twist ratio ( R T‐S ). Second, kinematic decoupling at the assembly scale localizes torsional deformation as a boundary‐decoupled internal rotational mode, while maintaining external interfaces in pure translation. This cross‐scale framework establishes a deployable paradigm bridging metamaterial physics and robotic systems operating in geometrically constrained environments.