| 1. |
Kazuya Saito, Akinobu Fujimoto, Yoji Okabe, Constructing Three-Dimensional Honeycomb Structures Based on Origami Geometry, Journal of Mechanisms and Robotics, 10.1115/1.4055823, 1-15, 2022.09, Abstract
Origami has shown the potential to design unique mechanical properties and complex three-dimensional shapes by folding through designed crease patterns on flat materials. The authors investigated a new honeycomb-based origami metamaterial called “kirigami honeycomb.” Resembling origami, kirigami honeycomb allows a single flat sheet of material with periodic slits to be folded into a honeycomb shape. Previous studies have reported successful use of this method to create various honeycomb shapes, changing only the folding line diagrams (FLDs). These previous studies have, however, considered only one-directional cross-section modifications; the core thickness and curvature changed in only the W-direction. This study proposes a new method that will support complex 3D honeycomb designs made from single flat sheets. A newly defined crease pattern conversion method provides arbitrary scaling of the honeycomb shape in the L-direction. The combined FLD and pattern conversion design methods encourage the cost-effective manufacture of 3D shaped honeycombs from single flat paper sheets. The proposed method is implemented to the design software, enabling to design arbitrary cross-section honeycomb cores with optional L-directional scaling.. |
| 2. |
Kazuya Saito, A study on diameter-dependent support selection of the tendrils of Cayratia japonica, Scientific Reports, 10.1038/s41598-022-08314-w, 12, 1, 2022.03, Abstract
Organisms make decisions when they perceive cues of varying intensities. In case of climbing plants, the diameter of supports in contact (tree or stem) is an important cue for their growth as plants that coil around a support with large diameter are unable to maintain tensional forces required for continued attachment to the support. The negative association between the diameter and the climbing success has been reported since Darwin published his study on climbing plants. However, it is not known if a climbing plant makes a decision to avoid a support with larger diameter. Here, we tested this possibility by observing the coiling response of tendrils of Cayratia japonica to supports with different diameters. The coiling success of the tendrils was affected by the diameter of the support and the tendril lengths. We propose a decision tree to describe the different phases of the coiling response and demonstrated that the tendrils change their coiling shape depending on the support diameter and the tendril length. To understand the behavioural rules regulating the phase pattern, we constructed a simple model with two assumptions on the tendril movement, (1) when the tendrils receive a contact stimulus, they begin to coil from around the contact point and (2) there is a minimum coiling angle at which the tendrils coil up, once the tendril starts coiling. Image analysis and 3D motion tracking technique revealed that the movement of the tendrils were consistent with the two assumptions of the model. The results suggested that the tendrils flexibly changed the coiling shapes depending on the support diameter and simple behavioural rules could regulate this diameter-dependent response.. |
| 3. |
Kazuya Saito, Hiroto Nagai, Kai Suto, Naoki Ogawa, Young ah Seong, Tomohiro Tachi, Ryuma Niiyama, Yoshihiro Kawahara, Insect wing 3D printing, Scientific Reports, 10.1038/s41598-021-98242-y, 11, 1, 18631-18631, 2021.12, AbstractInsects have acquired various types of wings over their course of evolution and have become the most successful terrestrial animals. Consequently, the essence of their excellent environmental adaptability and locomotive ability should be clarified; a simple and versatile method to artificially reproduce the complex structure and various functions of these innumerable types of wings is necessary. This study presents a simple integral forming method for an insect-wing-type composite structure by 3D printing wing frames directly onto thin films. The artificial venation generation algorithm based on the centroidal Voronoi diagram, which can be observed in the wings of dragonflies, was used to design the complex mechanical properties of artificial wings. Furthermore, we implemented two representative functions found in actual insect wings: folding and coupling. The proposed crease pattern design software developed based on a beetle hindwing enables the 3D printing of foldable wings of any shape. In coupling-type wings, the forewing and hindwing are connected to form a single large wing during flight; these wings can be stored compactly by disconnecting and stacking them like cicada wings.. |
| 4. |
Mudong Li, Sachiko Ishida, Kazuya Saito, Numerical evaluation on the out-of-plane properties of bio-inspired honeycomb cores with extra hollows, Proceedings of The 40th JSST Annual International Conference on Simulation Technology, 2021.09. |
| 5. |
Kazuya Saito, Chisaki Kitajima, 3D structural form creation of earwig fan using the algorithmic design tool, Proceedings of The 40th JSST Annual International Conference on Simulation Technology, 2021.09. |
| 6. |
斉藤 一哉, 岩元 真明, 中元 翔一, 田米開 三恵子, 折紙の幾何学に基づく斜角型ハニカムコアの開発とその視覚効果の検証, 応用数理学会論文集, 31, 3, 160-171, 2021.09. |
| 7. |
Kazuya Saito, Ricardo Pérez-de la Fuente, Kôichi Arimoto, Young ah Seong, Hitoshi Aonuma, Ryuma Niiyama, Zhong You, Earwig fan designing: Biomimetic and evolutionary biology applications, Proceedings of the National Academy of Sciences, 10.1073/pnas.2005769117, 117, 30, 17622-17626, 2020.07, Technologies to fold structures into compact shapes are required in multiple engineering applications. Earwigs (Dermaptera) fold their fanlike hind wings in a unique, highly sophisticated manner, granting them the most compact wing storage among all insects. The structural and material composition, in-flight reinforcement mechanisms, and bistable property of earwig wings have been previously studied. However, the geometrical rules required to reproduce their complex crease patterns have remained uncertain. Here we show the method to design an earwig-inspired fan by considering the flat foldability in the origami model, as informed by X-ray microcomputed tomography imaging. As our dedicated designing software shows, the earwig fan can be customized into artificial deployable structures of different sizes and configurations for use in architecture, aerospace, mechanical engineering, and daily use items. Moreover, the proposed method is able to reconstruct the wing-folding mechanism of an ancient earwig relative, the 280-million-year-oldProtelytron permianum. This allows us to propose evolutionary patterns that explain how extant earwigs acquired their wing-folding mechanism and to project hypothetical, extinct transitional forms. Our findings can be used as the basic design guidelines in biomimetic research for harnessing the excellent engineering properties of earwig wings, and demonstrate how a geometrical designing method can reveal morphofunctional evolutionary constraints and predict plausible biological disparity in deep time.. |
| 8. |
Zekun Chang, Tung D. Ta, Koya Narumi, Heeju Kim, Fuminori Okuya, Dongchi Li, Kunihiro Kato, Jie Qi, Yoshinobu Miyamoto, Kazuya Saito, Yoshihiro Kawahara, Kirigami Haptic Swatches: Design Methods for Cut-and-Fold Haptic Feedback Mechanisms, Proceedings of the 2020 CHI Conference on Human Factors in Computing Systems, 10.1145/3313831.3376655, 1-12, 2020.04. |
| 9. |
Akihiro Doi, Yusuke Kono, Kimihiro Kimura, Satomi Nakahara, Tomoaki Oyama, Nozomi Okada, Yasutaka Satou, Kazuyoshi Yamashita, Naoko Matsumoto, Mitsuhisa Baba, Daisuke Yasuda, Shunsaku Suzuki, Yutaka Hasegawa, Mareki Honma, Hiroaki Tanaka, Kosei Ishimura, Yasuhiro Murata, Reiho Shimomukai, Tomohiro Tachi, Kazuya Saito, Naohiko Watanabe, Nobutaka Bando, Osamu Kameya, Yoshinori Yonekura, Mamoru Sekido, Yoshiyuki Inoue, Hiraku Sakamoto, Nozomu Kogiso, Yasuhiro Shoji, Hideo Ogawa, Kenta Fujisawa, Masanao Narita, Hiroshi Shibai, Hideyuki Fuke, Kenta Uehara, Shoko Koyama, A balloon-borne very long baseline interferometry experiment in the stratosphere: Systems design and developments, Advances in Space Research, 10.1016/j.asr.2018.09.020, 63, 1, 779-793, 2019.01, The balloon-borne very long baseline interferometry (VLBI) experiment is a technical feasibility study for performing radio interferometry in the stratosphere. The flight model has been developed. A balloon-borne VLBI station will be launched to establish interferometric fringes with ground-based VLBI stations distributed over the Japanese islands at an observing frequency of approximately 20 GHz as the first step. This paper describes the system design and development of a series of observing instruments and bus systems. In addition to the advantages of avoiding the atmospheric effects of absorption and fluctuation in high frequency radio observation, the mobility of a station can improve the sampling coverage ("uv-coverage") by increasing the number of baselines by the number of ground-based counterparts for each observation day. This benefit cannot be obtained with conventional arrays that solely comprise ground-based stations. The balloon-borne VLBI can contribute to a future progress of research fields such as black holes by direct imaging. (C) 2018 Published by Elsevier Ltd on behalf of COSPAR.. |
| 10. |
倉川 正也, 奥泉 信克, 森 治, 佐藤 泰貴, 宮崎 康行, 坂本 啓, 菅原 佳城, 斎藤 一哉, Kurakawa Masaya, Okuizumi Nobukatsu, Mori Osamu, Sato Yasutaka, Miyazaki Yasuyuki, Sakamoto Hiraku, Sugawara Yoshiki, Saito Kazuya, 展開膜面における巻き付け方法の解析的研究, [第28回アストロダイナミクスシンポジウム講演後刷り集] = The 28th Workshop on JAXA Astrodynamics and Flight Mechanics, 166, 365-370, 2018.07, 第28回アストロダイナミクスシンポジウム (2018年7月30-31日. 宇宙航空研究開発機構宇宙科学研究所), 相模原市, 神奈川県資料番号: SA6000135021レポート番号: A-21. |
| 11. |
斉藤 一哉, 五島 庸, 王 麗君, 岡部 洋二, 折紙の数理を応用したハニカム構造材料の新しい製造法, 応用数理, 28, 1, 26-31, 2018.03, . |
| 12. |
Jinxiang Chen, Xiaoming Zhang, Yoji Okabe, Kazuya Saito, Zhensheng Guo, Longcheng Pan, The deformation mode and strengthening mechanism of compression in the beetle elytron plate, MATERIALS & DESIGN, 10.1016/j.matdes.2017.06.014, 131, 481-486, 2017.10, For the development of lightweight biomimetic functional-structural materials, the compressive deformation mode of beetle elytron plates (BEPs) and their strengthening mechanism of high energy absorption were investigated, with the following results: compared with honeycomb plates, the compressive strength and the energy absorption properties of BEPs are significantly increased. This is because in a BEP, the hollow trabeculae with high torsional stiffness cause the deformation behavior to be dominated by compression, generating a convex curve with three half-waves, which is consistent with the deformation of the honeycomb walls. This study reveals not only the compressive deformation mode and the mechanism of high energy absorption in BEPs but also the relationship between the biological prototype of a BEP and its function. The findings show that BEPs represent a significant improvement over honeycomb plates and show potential for widespread application as novel energy-absorbing sandwich structures. (C) 2017 Elsevier Ltd. All rights reserved.. |
| 13. |
斉藤 一哉, 五島 庸, 折紙工法ハニカムコアの産業応用 (特集 折紙工学の最前線 : 基礎から応用まで), 金属, 87, 10, 836-842, 2017.10. |
| 14. |
Kazuya Saito, Tomohiro Tachi, Ryuma Niiyama, Yoshihiro Kawahara, Design of a beetle inspired deployable wing, Proceedings of the ASME Design Engineering Technical Conference, 10.1115/DETC2017-67697, 5, 2017.08, This study primarily proposes a procedure to design a crease pattern for beetle-inspired deployable wings based on the hindwings in relatively large-sized beetles like horn beetle or chafer. First, we discuss the representative patterns of wing supports and crease lines based on previous entomological research and propose a basic geometry for the artificial wing. Next, the flat foldability and rigid foldability of the proposed crease pattern are discussed based on origami geometry. Geometrical restrictions for flat- and rigid-foldable wings are numerically expressed as a function of the design parameters, and the Newton-Raphson method is used to compute the actual solutions. Although researchers have attempted to characterize the representative crease patterns found in beetles, only flat foldability has been considered in previous research. Our proposed method enables the design of rigid-foldable wings based on beetle-inspired patterns, which is considered beneficial in designing the deployable structures.. |
| 15. |
Kazuya Saito, Shuhei Nomura, Shuhei Yamamoto, Ryuma Niyama, Yoji Okabe, Investigation of hindwing folding in ladybird beetles by artificial elytron transplantation and microcomputed tomography, PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA, 10.1073/pnas.1620612114, 114, 22, 5624-5628, 2017.05, Ladybird beetles are high-mobility insects and explore broad areas by switching between walking and flying. Their excellent wing transformation systems enabling this lifestyle are expected to provide large potential for engineering applications. However, the mechanism behind the folding of their hindwings remains unclear. The reason is that ladybird beetles close the elytra ahead of wing folding, preventing the observation of detailed processes occurring under the elytra. In the present study, artificial transparent elytra were transplanted on living ladybird beetles, thereby enabling us to observe the detailed wing-folding processes. The result revealed that in addition to the abdominal movements mentioned in previous studies, the edge and ventral surface of the elytra, as well as characteristic shaped veins, play important roles in wing folding. The structures of the wing frames enabling this folding process and detailed 3D shape of the hindwing were investigated using microcomputed tomography. The results showed that the tape spring-like elastic frame plays an important role in the wing transformation mechanism. Compared with other beetles, hindwings in ladybird beetles are characterized by two seemingly incompatible properties: (i) the wing rigidity with relatively thick veins and (ii) the compactness in stored shapes with complex crease patterns. The detailed wing-folding process revealed in this study is expected to facilitate understanding of the naturally optimized system in this excellent deployable structure.. |
| 16. |
Kazuya SAITO, Nobukatsu OKUIZUMI, Hiraku SAKAMOTO, Junji KIKUCHI, Jun MATSUMOTO, Hiroshi FURUYA, Osamu MORI, Experimental Research on Roll-up Storage Method for a Large Solar Sail, Proceedings of The fourth International Symposium on Solar Sailing (ISSS 2017), 2017.01. |
| 17. |
Kazuya Saito, Akinobu Fujimoto, Yoji Okabe, Design of a 3D wing honeycomb core based on origami techniques, Proceedings of the ASME Design Engineering Technical Conference, 10.1115/DETC2016-60419, 5, 2016.08, Honeycomb cores, which offer substantial weight reductions in design, are used in various engineering fields. For antenna reflector and rotor blade designs, Three-dimensional (3D) honeycomb cores are in considerable demand. 3D honeycombs are typically manufactured by curving or carving flat honeycombs. High associated manufacturing costs have limited their application. The authors of this paper investigated a new honeycomb design and manufacturing method called "kirigami honeycomb." Resembling origami, kirigami honeycomb allows a single flat sheet of material with periodic slits to be folded into a honeycomb shape. Previous studies have reported successful use of this method to create various honeycomb shapes, changing only the folding line diagrams (FLDs). These previous studies have, however, considered only one-directional crosssection modifications
the core thickness and curvature changed in only the W-direction. This study proposes a new method that will support complex 3D double-curved honeycomb designs made from single flat sheets. A newly defined crease pattern conversion method provides arbitrary scaling of the honeycomb shape in the L-direction. The combined FLD and pattern conversion design methods encourage the cost-effective manufacture of 3D wing shaped honeycombs from single flat paper sheets. Wind or tidal power generation industries that use rotor blades could benefit from this design.. |
| 18. |
Kazuya Saito, Akinobu Fujimoto, Lijun Wang, Yoji Okabe, Design of single/double curved honeycomb cores based on origami techniques, Proceedings of IASS 2016 Tokyo Symposium: Spatial Structures in the 21st Century – Origami, 2016.08. |
| 19. |
斉藤 一哉, 折紙と展開構造 (特集 折紙工学の深化と新しい潮流), 応用数理, 26, 1, 9-14, 2016.03, This study presents a new method for designing self-deploying origami using the geometrically misaligned creases. In this method, some facets are replaced by "holes" such that the systems become a 1-DOF mechanism. These perforated origami models can be folded and unfolded similar to rigid-foldable (without misalignment) models because of their DOF despite the existence of the misalignment. Focusing on the removed facets, the holes will deform according to the motion of the frame of the remaining parts. In the proposed method, these holes are filled with elastic parts and store elastic energy for self-deployment. First, a new extended rigid-folding simulation technique is proposed to estimate the deformation of the holes. Next by using the above technique, the proposed method is applied on arbitrary-size quadrilateral mesh origami. Finally, by using the finite-element method, the authors conduct numerical simulations and confirm the deployment capabilities of the models.. |
| 20. |
Kazuya Saito, Yoji Okabe, Beetle Inspired Deployable Structures, Proceedings in the 26th International Conference on Adaptive Structures and Technologies, 2015.10. |
| 21. |
斉藤 一哉, 『屈曲性』と『強度』を両立させる新しいハニカム構造形成技術 (特集 「柔軟性・屈曲性」と「耐久・耐折性」の両立技術), Material stage, 15, 1, 42-48, 2015.04. |
| 22. |
Kazuya Saito, Sergio Pellegrino, Taketoshi Nojima, Manufacture of Arbitrary Cross-Section Composite Honeycomb Cores Based on Origami Techniques, JOURNAL OF MECHANICAL DESIGN, 10.1115/1.4026824, 136, 5, 51011, 2014.05, As observed in the design of antenna reflectors and rocket bodies, both flat and 3D-shaped honeycomb cores are used in the field of aerospace engineering. This study illustrates a new strategy to fabricate arbitrary cross-section honeycombs with applications of advanced composite materials by using the concept of the kirigami honeycomb, which is made from single flat sheets and has periodical slits resembling origami. The authors also describe a method of applying this technique to advanced composite materials. Applying the partially soft composite techniques, 3D shaped composite honeycombs are manufactured, and some typical samples are shown with their folding line diagrams.. |
| 23. |
Kazuya Saito, Fabio Agnese, Fabrizio Scarpa, A Cellular Kirigami Morphing Wingbox Concept, JOURNAL OF INTELLIGENT MATERIAL SYSTEMS AND STRUCTURES, 10.1177/1045389X11416030, 22, 9, 935-944, 2011.06, This study introduces the design and manufacturing of a wingbox based on a cellular hexagonal morphology and produced using kirigami techniques. The wingbox is manufactured in autoclave-cured woven Kevlar fabric using ply-cutting patterns designed around an airfoil profile. The cellular wingbox can be completely or partially folded, providing some shape-adapting capabilities for possible morphing applications. A numerical and analytical evaluation of the torsional stiffness of the wingbox with novel elastomeric face skins is also performed.. |
| 24. |
斉藤 一哉, 野島 武敏, 萩原 一郎, 新しく開発した軽量コアパネルの幾何学的パターンと機械的特性の関係, 日本機械学會論文集. A編 = Transactions of the Japan Society of Mechanical Engineers. A, 10.1299/kikaia.74.1580, 74, 748, 1580-1586, 2008.12, Dia-Core is a newly devised core panel formed by gluing/welding two same shaped panel pieces which have periodical indents. It has good cost performance due to easy press forming. Therefore, it is expected to become new core material which can be compete with honeycombs from the total points of view. The basic model of Dia-core is based on Octet-Truss developed by Fuller, and it consists of tetrahedra and octahedra. By varying the geometrical patterns that appear on the panel surfaces, various shaped modified models are devised systematically. In this paper, it is clarified that these pattern variations can be ruled by two geometric parameters, truncation [k ] and separation [s]. Next, by numerical simulation using FEM, effects of these two parameters on the representative properties of Dia-Core, bending and in-plane shear rigidity, are clarified.. |
| 25. |
斉藤 一哉, 野島 武敏, 平面/空間充填形に基づく新しい軽量高剛性コアパネルのモデル化, 日本機械学会論文集. A編 = Transactions of the Japan Society of Mechanical Engineers. A, 10.1299/kikaia.73.1302, 73, 735, 1302-1308, 2007.11, By processing triangle or square pyramid shaped indents on a flat sheet, panels with periodical indents in regular plane tiling patterns are manufactured. Highly rigid core panels are newly developed by setting this panel (as top panel) on a reversed one (as bottom panel), and gluing/ welding them at the apexes of pyramids to the vertexes of the tiling patterns in the bottom panel. The basic model named Dia-Core is a panel created in the form of Octet-Truss developed by Fuller which corresponds to the space filling model consisting of a combination of two tetrahedra and one octahedron. By varying the geometric patterns that appear on the panel surfaces, all possible patterns based on geometrical considerations are devised, systematically creating various modified models with larger welding portions.. |
| 26. |
野島 武敏, 杉山 文子, 斉藤 一哉, 折紙による機能構造と3次元構造のモデル化, 成形加工, 19, 6, 328-333, 2007.06. |
| 27. |
T Nojima, K Saito, Development of newly designed ultra-light core structures, JSME INTERNATIONAL JOURNAL SERIES A-SOLID MECHANICS AND MATERIAL ENGINEERING, 10.1299/jsmea.49.38, 49, 1, 38-42, 2006.01, By folding a thin flat sheet with periodically set slits or punched out portions into the third dimension, ultra-lightweight strong and functional core models are newly devised. The basic idea of this modeling arises from the application of origami technique to engineering. Based on the space filling models, fundamental flat cores and skew type sponge cores have been newly developed. By applying these models, such modified core models as curved cores and 3D honeycomb core are newly devised.. |
