▎ 摘　　要

The 3D variable-stiffness structure can realize shape programming, reconstruction, adaptation, and locking, and therefore, it has a wide design creation space. Accurate local stiffness control is of considerable significance to the design and application of 3D variable-stiffness structures although it is challenging. Herein, a 3D variable-stiffness structure realization scheme based on a patterned heating network is introduced. The laser-engraving and 3D-printing technologies are combined to obtain a 3D variable-stiffness structure composed of a patterned graphene-heating network (PGHN) and polylactic acid (PLA). The proposed scheme uses PGHN to accurately control the local stiffness of 3D PLA and realize programmable design and fabrication of 3D variable-stiffness structures. The "torsional structure," "hexagonal structure," and "spring" cases are used to elaborate the designability, excellent deformation and reconstruction capacity, and reasonable load bearing capacity of the PGHN/PLA variable-stiffness structure. A pneumatic disc, which is used as a reference for studies on shape control of PGHN/PLA variable-stiffness structures, is designed. Also, a pneumatic robot is designed based on the local stiffness control and shape-locking function of PGHN/PLA to achieve multimode motion control using a single air source. The PGHN/PLA variable-stiffness structure has potential applications in multimode robots, wearable devices, and deployable structures.