Department of Mechanical Engineering, Politecnico di Milano, Via La Masa 1, 20156, Milano, Italy.
Department of Biomechanical Engineering, Faculty of Mechanical, Maritime, and Materials Engineering, Delft University of Technology (TU Delft), Mekelweg 2, 2628 CD, Delft, The Netherlands.
Sci Rep. 2018 Jan 17;8(1):965. doi: 10.1038/s41598-018-19381-3.
Architectured materials with rationally designed geometries could be used to create mechanical metamaterials with unprecedented or rare properties and functionalities. Here, we introduce "shape-matching" metamaterials where the geometry of cellular structures comprising auxetic and conventional unit cells is designed so as to achieve a pre-defined shape upon deformation. We used computational models to forward-map the space of planar shapes to the space of geometrical designs. The validity of the underlying computational models was first demonstrated by comparing their predictions with experimental observations on specimens fabricated with indirect additive manufacturing. The forward-maps were then used to devise the geometry of cellular structures that approximate the arbitrary shapes described by random Fourier's series. Finally, we show that the presented metamaterials could match the contours of three real objects including a scapula model, a pumpkin, and a Delft Blue pottery piece. Shape-matching materials have potential applications in soft robotics and wearable (medical) devices.
具有合理设计几何形状的结构材料可用于创建具有前所未有或罕见性能和功能的机械超材料。在这里，我们介绍了“形状匹配”超材料，其中包含负泊松比和常规单元的多孔结构的几何形状被设计为在变形时呈现出预定的形状。我们使用计算模型将平面形状的空间向前映射到几何设计的空间。首先通过将其预测与使用间接增材制造制造的试样的实验观察进行比较，验证了基础计算模型的有效性。然后，使用前向映射来设计多孔结构的几何形状，以近似由随机傅里叶级数描述的任意形状。最后，我们表明所提出的超材料可以匹配包括肩胛骨模型、南瓜和代尔夫特蓝陶器在内的三个实际物体的轮廓。形状匹配材料在软机器人和可穿戴（医疗）设备中有潜在的应用。
