2023 年 89 巻 917 号 p. 22-00273
Here we propose a new method to generate Kirigami honeycomb for complicated structures. Although commercially available honeycombs have the same cross-section as standard, Nojima and Saito firstly showed honeycombs could be curved by using the Kirigami operation. By this, the Kirigami honeycomb has become a mighty treasure trove of metamaterial creation, so Kirigami has been an international language like Origami and it has been a hot topic in the Origami engineering community. So far, there is an overlap in the development view of the honeycomb core with a non-convex curved surface and the development view cannot be used for the construction of the core with a non-convex curved surface. Moreover, with conventional methods, STL(Stereolithography) data which are often used by the additive 3D printer can be used only after the formulas on the upper and lower surfaces are obtained. Since with the conventional methods, only the structure that can be completed by the information of the upper and lower surface formulas can be handled, they cannot treat a structure with a non-uniform shape between the upper and lower surfaces, and also curvature and thickness can only change in one axis. With this proposed method, firstly the target structure expressed in CAD and/or STL data is covered with a honeycomb core of any shape in any direction. Secondly, the intersections of the two are obtained and at last it is obtained the honeycomb core peculiar to the structure of the prepared honeycomb base. That is, the proposed one is extremely general like the present additive 3D printer. The biggest drawback of the Kirigami honeycomb is that the material yield is not always good for which this proposed method is also advantageous because it can select the orientation of the honeycomb cell in which material yield is maximized.
