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Abstract Mechanical metamaterials are known for their prominent mechanical characteristics such as programmable deformation that are due to periodic microstructures. Recent research trends have shifted to utilizing mechanical metamaterials as structural substrates to integrate with functional materials for advanced functionalities beyond mechanical, such as active sensing. This study reports on the ultra‐stretchable kirigami piezo‐metamaterials (KPM) for sensing coupled large deformations caused by in‐ and out‐of‐plane displacements using the lead zirconate titanate (PZT) and barium titanate (BaTiO3) composite films. The KPM are fabricated by uniformly compounding and polarizing piezoelectric particles (i.e., PZT and BaTiO3) in silicon rubber and structured by cutting the piezoelectric rubbery films into ligaments. Characterizes the electrical properties of the KPM and investigates the bistable mechanical response under the coupled large deformations with the stretching ratio up to 200% strains. Finally, the PZT KPM sensors are integrated into wireless sensing systems for the detection of vehicle tire bulge, and the non‐toxic BaTiO3 KPM are applied for human posture monitoring. The reported kirigami piezo‐metamaterials open an exciting venue for the control and manipulation of mechanically functional metamaterials for active sensing under complex deformation scenarios in many applications.

The majority of the existing studies on chiral metamaterials have focused on the mechanism, fabrication and optimization of the structure-induced chirality, while the studies on the material perspective are scarce. Functional materials such as shape memory polymers (SMPs) open a promisingly emerging venue for improving the performance of chiral metamaterials from the material perspective. Here, the graphene-reinforced shape memorable chiral metamaterials (GR-SMCM) with self-adaptive thermomechanical response under thermal excitations are reported. Theoretical models are developed to consider the chiral metamaterials designed in the planar and tubular structures using the graphene-reinforced SMPs (GR-SMPs). The modified phase evolution-based constitutive model is expanded for the material influence of GR-SMPs, and the chiral compatibility is analyzed to examinate the structural influence of chiral metamaterials. Experiments and numerical simulations are conducted to validate the proposed theoretical models and great agreements are obtained. Parametric studies are carried out to investigate the tunability of the Young’s modulus, Poisson’s ratio, rotation angle of the hexagonal cells and temperature sensitivity. The reported GR-SMCM provide an efficacious approach to obtain self-adaptive performance with excellent controllability, which can be used to design advanced thermomechanical devices such as temperature sensing devices.