Recent advances in active materials and fabrication techniques have enabled the production of cyclically self-deployable metamaterials with an expanded functionality space. However, designing metamaterials that possess continuously tunable mechanical properties after self-deployment remains a challenge, notwithstanding its importance. Inspired by push puppets, we introduce an efficient design strategy to create reversibly self-deployable metamaterials with continuously tunable post-deployment stiffness and damping. Our metamaterial comprises contracting actuators threaded through beads with matching conical concavo-convex interfaces in networked chains. The slack network conforms to arbitrary shapes, but when actuated, it self-assembles into a preprogrammed configuration with beads gathered together. Further contraction of the actuators can dynamically tune the assembly's mechanical properties through the beads' particle jamming, while maintaining the overall structure with minimal change. We show that, after deployment, such metamaterials exhibit pronounced tunability in bending-dominated configurations: they can become more than 35 times stiffer and change their damping capability by over 50%. Through systematic analysis, we find that the beads'conical angle can introduce geometric nonlinearity, which has a major effect on the self-deployability and tunability of the metamaterial. Our work provides routes towards reversibly self-deployable, lightweight, and tunable metamaterials, with potential applications in soft robotics, reconfigurable architectures, and space engineering.

翻译：近年来，活性材料与制造技术的进步使得循环自展开超材料的生产成为可能，并拓展了其功能空间。然而，设计在自展开后仍具备连续可调机械性能的超材料，尽管具有重要意义，目前仍是一个挑战。受推线木偶的启发，我们提出了一种高效的设计策略，用于创建可逆自展开且展开后刚度和阻尼连续可调的超材料。该超材料由收缩致动器构成，这些致动器穿过具有匹配锥形凹凸界面的珠体，并连接成网络链。松弛的网络可贴合任意形状，但在致动时，它会自组装成预编程构型，珠体聚集在一起。致动器的进一步收缩可通过珠体的颗粒阻塞效应动态调节组件的机械性能，同时保持整体结构基本不变。我们证明，此类超材料在展开后，在弯曲主导的构型中表现出显著的可调性：其刚度可提升超过35倍，阻尼能力变化超过50%。通过系统分析，我们发现珠体的锥角会引入几何非线性，这对超材料的自展开能力和可调性具有重要影响。我们的工作为开发可逆自展开、轻质且可调的超材料提供了途径，在软体机器人、可重构结构和空间工程等领域具有潜在应用前景。