Rotation-Based Snap-Fit Mechanical Metamaterials

Multistable mechanical metamaterials have broad application prospects in various fields due to their unique configuration transformation ability, such as energy absorption, shape reconstruction, soft actuator design, mechanical storage, and logic operation. Currently, the steady-state transition mechanisms for most multistable mechanical metamaterials rely on translational displacement input, while the rotational input mechanisms are rarely studied. Here, a curved beam snap-fit structure is proposed to realize the multistable transition of metamaterials under rotational load. Their mechanical characteristics and influencing factors are discussed in detail through theoretical analysis, numerical simulation, and experimental verification. In addition, related rotational multistable mechanical metamaterials prototypes are designed. Their potential applications in the fields of energy absorption or robotics are demonstrated, which opens up new ideas and directions for the multifunctional applications of mechanical metamaterials.