記述言語：その他   掲載種別：研究論文（学術雑誌）  

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.

DOI： 10.1115/1.4055823

記述言語：英語   掲載種別：研究論文（学術雑誌）  

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.

DOI： 10.1038/s41598-022-08314-w

記述言語：英語   掲載種別：研究論文（学術雑誌）  

<title>Abstract</title>Insects 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.

DOI： 10.1038/s41598-021-98242-y

記述言語：英語  

記述言語：英語   掲載種別：研究論文（その他学術会議資料等）  

記述言語：日本語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

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-old<italic>Protelytron permianum</italic>. 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.

DOI： 10.1073/pnas.2005769117

記述言語：英語   掲載種別：研究論文（その他学術会議資料等）  

DOI： 10.1145/3313831.3376655

記述言語：その他   掲載種別：研究論文（学術雑誌）  

DOI： 10.1587/comex.2019GCL0031

記述言語：英語   掲載種別：研究論文（その他学術会議資料等）  

DOI： 10.1145/3290605.3300858

記述言語：その他   掲載種別：研究論文（その他学術会議資料等）  

DOI： 10.1145/3290607.3312757

記述言語：その他   掲載種別：研究論文（その他学術会議資料等）  

DOI： 10.1145/3290607.3312872

記述言語：日本語  

折り紙は、大きな構造をコンパクトに収納できる性質から宇宙展開構造物に、軽さと強さを兼ね備えた折り紙構造建築になど、様々な分野に応用されてきた。近年では、折り紙の小面を電極として用いることで、キャパシタやスピーカーなどの電子回路的な応用が増えた。平坦折りできる展開図は2色に塗り分けられることが古くから知られている一方で、ジャンプワイヤなどの手間が不要になる「連結した2色への塗り分け」は考慮されてこなかった。本論文では、「どのような展開図ならば連結した2色への塗り分けパターンが存在するか？」の判別法と、「塗り分け不可能なパターンを塗り分けるためにどのような修正が可能か？」を紹介する。

記述言語：英語   掲載種別：研究論文（学術雑誌）  

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.

DOI： 10.1016/j.asr.2018.09.020

記述言語：英語   掲載種別：研究論文（その他学術会議資料等）  

Crawling Cylindrical Origami Robot Driven by Single Actuator

記述言語：英語  

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

記述言語：日本語  

ロボットを用いた電線のメンテナンスロボットなど、直線状の物体上に沿って移動するロボットが存在する。そのようなロボットを我々は折り紙で実現する手法を提案する。直線上の物体を包み込むように円筒折を配置し、その展開と収縮で移動する。円筒折は折れると内径が小さくなる構造である。内径が小さくなることで直線状の物体を把持する。異なる剛性の円筒折を組み合わせることで、最も剛性の小さい円筒折から順に折れ、最も剛性の小さい円筒折から展開する。これにより、ロボットを伸縮させるだけで、剛性が小さい円筒折の方向に進行する。形状記憶合金や、内部への気体の封入で駆動することで、ロボットの軽量化が可能である。

記述言語：日本語  

本研究では,折紙のように1枚のシートからの折り曲げのみで構成される3次元の体躯に,アクチュエータとしての形状記憶合金を付けることで実現する,伸縮運動により這行運動をするシンプルなイモムシ型ロボットを実装する。このロボットは機械的機構が簡潔で,極めて安価に作製可能であり,伸縮の波の伝播方向を変えるだけでロボットの進行方向を制御することも可能である。本稿では,この折り紙ロボットの体節伸縮の波伝播運動のメカニズムに着目し,折り目の構造及び形状記憶合金が発生させる力の大きさとタイミングを分析し,効率的な這行運動を生成可能なパターンを見つけ出す。

記述言語：日本語  

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記述言語：日本語  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

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.

DOI： 10.1016/j.matdes.2017.06.014

記述言語：英語   掲載種別：研究論文（その他学術会議資料等）  

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.

DOI： 10.1115/DETC2017-67697

記述言語：英語  

DOI： 10.1073/pnas.1709196114

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Design and fabrication of aluminum honeycomb structures based on origami technology

記述言語：英語   掲載種別：研究論文（学術雑誌）  

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.

DOI： 10.1073/pnas.1620612114

記述言語：その他   掲載種別：研究論文（その他学術会議資料等）  

Experimental Research on Roll-up Storage Method for a Large Solar Sail

記述言語：その他   掲載種別：研究論文（その他学術会議資料等）  

Design of single/double curved honeycomb cores based on origami techniques

記述言語：英語   掲載種別：研究論文（その他学術会議資料等）  

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.

DOI： 10.1115/DETC2016-60419

記述言語：日本語  

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.

記述言語：英語   掲載種別：研究論文（学術雑誌）  

In this study, a phase-shifted fiber Bragg grating sensor was employed for acoustic emission detection in cross-ply carbon fiber-reinforced plastic laminates. First, we evaluated the response of the phase-shifted fiber Bragg grating sensor to a simulated acoustic emission source using a pencil lead breakage test. The existing modes of Lamb waves were observed, and their relations to the acoustic emission source orientation were investigated using a modal acoustic emission method for discriminating between acoustic emission signals generated by transverse cracking and delamination. As a result, those two types of damage were identified during a tensile test. In the time-frequency analysis of the waveforms detected by the phase-shifted fiber Bragg grating sensor, in addition to the S-0 and A(0) modes that are usually used in modal acoustic emissions, we found an A(1) mode in the high-frequency range of the acoustic emission generated by a transverse crack. Then, we conducted a finite element analysis to examine the inherent mechanism of the A(1) mode excitation. The results of the calculation almost agreed with the experimental results and indicated that a phase-shifted fiber Bragg grating sensor has a high sensitivity response to acoustic emission in the carbon fiber-reinforced plastic laminates over a broad bandwidth. Therefore, this novel fiber-optic sensor has been shown to have high potential for monitoring the ultrasonic structural health of composites.

DOI： 10.1177/1475921715624503

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Usually, origami-based morphing structures are designed on the premise of 'rigid folding', i.e. the facets and fold lines of origami can be replaced with rigid panels and ideal hinges, respectively. From a structural mechanics viewpoint, some rigid-foldable origami models are overconstrained and have negative degrees of freedom (d.f.). In these cases, the singularity in crease patterns guarantees their rigid foldability. 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-d.f. mechanism. These perforated origami models can be folded and unfolded similar to rigid-foldable (without misalignment) models because of their d.f. 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, 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.

DOI： 10.1098/rspa.2015.0235

記述言語：その他   掲載種別：研究論文（その他学術会議資料等）  

Beetle Inspired Deployable Structures

記述言語：日本語  

Foldable hindwings in beetles are one of the ultimate deployable structures. They have sufficient strength and stiffness to tolerate 20-1000 beats per second in the flight position, although they can be folded and unfolded nearly instantly depending on the situation. This study focuses on a group of beetles that have unfolding-stable-type wings and aims to reveal their wing-folding/unfolding mechanisms. These beetles use their wing elasticity for deployment and can therefore quickly take off. First, on the basis of the reports of entomologists, the authors describe the factors related to the actuation of insect wing folding and unfolding. Then, the detailed motions involved in take-off and wing storing in ladybird beetles and rove beetles are observed by a high-speed camera. The analysis of these movies reveals the detailed processes of wing-unfolding and folding in these two species. Intrinsic elasticity plays a major role in wing development in both species. In the case of wing storing, a ladybird beetle folds its hindwings into a symmetric pattern using a simple up-down movement of the abdomen, whereas rove beetles also use their abdomens for wing-folding, but their movements are more complex, and the crease patterns are asymmetric. Finally, the characteristics of each wing-folding mechanism are summarized and the potential for engineering applications are discussed. Wing-folding/unfolding mechanisms in these insects have various unique capabilities which will provide new possibilities for designing deployable structures.

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Utilizing optical fiber technique to structural health monitoring of composite materials is attracting attention recently due to the inherent advantages in optical fiber sensor. However, acoustic emission signals with low energy and high frequency from transverse cracks in carbon fiber-reinforced plastic laminates are difficult to be detected by normal optical techniques. In this work, we present a phase-shifted fiber Bragg grating balanced sensing system to detect acoustic emission signals generated in a carbon fiber-reinforced plastic laminate in a three-point bending test. We demonstrated that the phase-shifted fiber Bragg grating balanced sensing system with a broad bandwidth and high sensitivity can detect high-frequency, low-energy acoustic emission signals caused by transverse cracks. In our experiments, the transverse cracks were identified very well through the detected acoustic emission signals. The relationship between the strain and the acoustic emission signals, and the typical waveforms of the acoustic emission signals were investigated. Furthermore, accurate position identification using acoustic emission detection by the phase-shifted fiber Bragg grating sensor was demonstrated. All the results obtained from the phase-shifted fiber Bragg grating sensor were compared to the results obtained from commercial lead-zirconate-titanate acoustic emission sensors. We found that the phase-shifted fiber Bragg grating balanced sensing system performance was comparable to the commercial lead-zirconate-titanate acoustic emission sensors.

DOI： 10.1177/1475921714560074

記述言語：日本語  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Traditionally, origami-based structures are designed on the premise of "rigid folding," However, every act of folding and unfolding is accompanied by elastic deformations in real structures. This study focuses on these elastic deformations in order to expand origami into a new method of designing morphing structures. The authors start by proposing a simple model for evaluating elastic deformation in nonrigid origami structures. Next, these methods are applied to deployable plate models. Initial strain is introduced into the elastic parts as actuators for deployment. Finally, by using the finite element method (FEM), it is confirmed that the proposed system can accomplish the complete deployment in 3 x 3 Miura-or model.

DOI： 10.1115/1.4029228

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Foldable wings of insects are the ultimate deployable structures and have attracted the interest of aerospace engineering scientists as well as entomologists. Rove beetles are known to fold their wings in the most sophisticated ways that have right-left asymmetric patterns. However, the specific folding process and the reason for this asymmetry remain unclear. This study reveals how these asymmetric patterns emerge as a result of the folding process of rove beetles. A high-speed camera was used to reveal the details of the wing-folding movement. The results show that these characteristic asymmetrical patterns emerge as a result of simultaneous folding of overlapped wings. The revealed folding mechanisms can achieve not only highly compact wing storage but also immediate deployment. In addition, the right and left crease patterns are interchangeable, and thus each wing internalizes two crease patterns and can be folded in two different ways. This two-way folding gives freedom of choice for the folding direction to a rove beetle. The use of asymmetric patterns and the capability of two-way folding are unique features not found in artificial structures. These features have great potential to extend the design possibilities for all deployable structures, from space structures to articles of daily use.

DOI： 10.1073/pnas.1409468111

記述言語：日本語  

Artful wing folding of insects has attracted the interest of aerospace engineering scientists as well as entomologists. Foldable hindwings are the ultimate deployable structures. They have sufficient strength and stiffness to tolerate 20-1000 beats per second in the flight position, although they can be folded and unfolded instantly depending on the situation. Entomologists point out that insect wings can be classified into the following two groups based on structural characteristics: folding-stable type and unfolding-stable type. In each group, the movement toward a stable point is easy to achieve because it can be triggered by a small force and progresses automatically by elastic force. Naturally, problems are observed mainly in reverse-directed movements that require a larger force to cross the peak of elastic energy. Some insects address these problems by unique and somewhat heavy-handed methods. Despite large potential for engineering application, few studies have been undertaken to reveal these characteristic movements. This study used a high-speed camera to observe the folding and unfolding movements of some beetles. The revealed folding/unfolding mechanisms can achieve not only highly compact wing storage but also immediate deployment/folding. They offer significant potential for space deployable structures.

記述言語：日本語  

In this research, phase-shifted FBG (PS-FBG) sensor was employed to practical AE detection for carbon fiber reinforced plastic (CFRP) composite laminate. Firstly, we evaluated the characteristics of AE signals detected by this kind of sensor. Secondly, through the experiment and simulation concerning AE source orientation, quantitative information about the standard for discriminating the AE signals due to transverse cracks and delaminations was obtained. Finally, according to the standard, we identified the occurrence of those two damage types successfully from the actually detected AE signals under three point bending and tensile tests.

記述言語：日本語  

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.

記述言語：英語   掲載種別：研究論文（学術雑誌）  

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.

DOI： 10.1115/1.4026824

記述言語：英語   掲載種別：研究論文（学術雑誌）  

In this research, the sensitivity distribution properties of a phase-shifted fiber Bragg grating (PS-FBG) to ultrasonic waves were investigated employing the surface attachment method. A careful consideration was taken and examined by experimental results to explain that the distances and angles between the sensor and ultrasonic source influence not only the amplitudes, but also the initial phases, waveforms, and spectra of detected signals. Furthermore, factors, including the attachment method and the material's geometric dimensions, were also discussed. Although these results were obtained based on PS-FBG, they are also applicable to a normal FBG sensor or even an optical fiber sensor, due to the identical physical changes induced by ultrasonic waves in all three. Thus, these results are useful for applications of optical fiber sensors in non-destructive testing and structural health monitoring.

DOI： 10.3390/s140101094

記述言語：日本語  

Evaluation of AE signals detected by an optical fiber sensor to identify the damage in composites

記述言語：日本語  

Damage detection in fiber metal laminates using the mode conversion of the lamb wave

記述言語：日本語  

AE detection in CFRP composites by a novel optical fiber sensor

記述言語：日本語  

This paper presents a new impact identification method using the high-speed strain measurement system. This system consists of fiber Bragg grating (FBG) sensors and an arrayed waveguide gratings (AWG) filter, and can detect large strain waves such as the impact strain waves. Firstly, we propose new algorism for calculation of coordinates of the impact-loaded point. Although conventional detection methods are carried out under the condition that the propagation speed of the elastic wave is given, this proposed method enables us to calculate the position of a wave source without its speed. This algorism also has the great versatility of sensors positions. Next, the high-speed strain measurement system used in this study is mentioned. Using multiplexed FBG sensors, this system can detect the strain wave on four different points at the same time. Finally, the impact identification tests are carried out on the carbon Fiber reinforced plastic (CFRP) laminate. The aforementioned algorism are used to calculate the impact loaded position from the difference for the arrival times of the four sensor points. The results indicate the correct position with relatively small errors.

記述言語：日本語  

As represented by Miura-ori, origami has inspired various types of deployable structures. Usually, these Origami structures are designed under the assumption of "rigid folding", which means each plane is undeformable and connected with ideal joints. The authors proposed a new strategy for designing deployable structures by using partially elastic origami models. These new origami structures take into account the elastic deformation. It enables us to estimate the elastic energy through folding and unfolding process and to design self-deploying origami structures. This paper presents the manufacturing methods for the deployable structures based on partially elastic origami. The challenge is summarized in two main problems: treating of plate thickness and designing for hinge parts. Firstly, the authors propose the method using commercially available hinges and make the sample of aluminum alloy plate. Secondly, by using 3D printer, some plastic samples are made and the representative one is shown. Finally, the deformations of elastic parts in these trial models are compared with a theoretical model.

記述言語：日本語  

As represented by Miura-ori, origami has inspired various types of deployable structures. Usually, these Origami structures are designed under the assumption of "rigid folding", which means each plane is undeformable and connected with ideal joints. The authors proposed a new strategy for designing deployable structures by using partially elastic origami models. These new origami structures take into account the elastic deformation. It enables us to estimate the elastic energy through folding and unfolding process and to design self-deploying origami structures. This paper presents the manufacturing methods for the deployable structures based on partially elastic origami. The challenge is summarized in two main problems: treating for plate thickness and designing for hinge parts. Firstly, the authors propose the method using commercially available hinges and make the sample from of aluminum alloy plate. Secondly, by using 3D printer, some plastic samples are made and the representative one is shown. Finally, the deformations of elastic parts in these trial models are compared with a theoretical model.

記述言語：日本語  

As represented by Miura-ori, origami has inspired various types of deployable structures. Usually, these Origami structures are designed under the assumption of "rigid folding", which means each plane is undeformable and connected with ideal joints. In this study, a new strategy for designing deployable structures are proposed by using partially elastic origami models. These new origami structures take into account the elastic deformation. It enables us to estimate the elastic energy through folding and unfolding process and to design self-deploying origami structures.

記述言語：日本語  

As represented by Miura-ori, origami has inspired various types of deployable structures. Usually, these Origami structures are designed under the assumption of "rigid folding", which means each plane is undeformable and connected with ideal joints. In this study, a new strategy for designing deployable structures are proposed by using partially elastic origami models. These new origami structures take into account the elastic deformation. It enables us to estimate the elastic energy through folding and unfolding process and to design self-deploying origami structures.

記述言語：日本語  

222 Designing Method for 3D Honeycomb Cores

記述言語：英語   掲載種別：研究論文（学術雑誌）  

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.

DOI： 10.1177/1045389X11416030

記述言語：日本語  

Dia-Core is a newly devised core panel formed by gluing/welding of two same shaped panel pieces which have periodically indents. The basic model of Dia-core is based on Octet-Truss developed by Fuller, and it consists of tetrahedra and octahedra. It has good cost performance due to easy press forming. Therefore, it is expected to become new core materials which can compete with honeycomb panels from the total points of view. In this paper, by using experiments and numerical simulations, the bending rigidity, a representative propertie of Dia-Core is clarified. The results suggest that the bending rigidity of Dia-core is proportional to the initial thickness of panel pieces and the square of the panel height. These trends can be explained by the application of the theory of sandwich structures. And by using these results, the specific rigidity of Dia-core is calculated and compared with that of two typical honeycomb panels.

記述言語：日本語  

In this paper, we present the vibration analyses of Trass core panel. Trass core panel is newly devised lightweight core panel and has general versatility. We conducted the vibration analyses and excitation experiment to obtain the vibration characteristics such as Eigen frequency and Eigen mode, then we compared the Eigen frequency of a Trass core panel to that of the flat panel which weight is equal to the Trass core panel.

記述言語：日本語  

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.

DOI： 10.1299/kikaia.74.1580

記述言語：日本語  

933 Press Forming Analysis and Strength Characteristic after Forming for Truss Core Panel based on Geometrical Patterns

記述言語：日本語  

平面/空間充填形の概念に基づいて開発された新しいコアパネル(ダイアコア)は,プレス加工されたパネル片を2枚対称に接合することによりハニカムコアよりもはるかに安価に製作できる.それゆえ実用化されれば様々な製品への応用が期待され,オクテットトラス型の基本モデル以外にも様々なデザインを持つ多数の発展型モデルが開発されている.本論文はその多様な幾何学的パターンを2つのパラメータを用いて数理的に表す方法を明らかにすると共に,有限要素法を用いてこれらのパラメータがパネルの曲げ剛性,面内せん断剛性に与える影響を明らかにする.

記述言語：日本語  

This paper deals with a new core structure panel, called Truss Core Panel. We consider this Panel is useful for environment concern, because this panel has high-specific stiffness, such as Honey Comb Panel. And more, this Panel is formed by Press Forming. So, we think it leads more general versatility unlike Honey Comb Panel that has multi forming process. And now Truss Core Panel changes its core shape based on Truncation parameter, k and Separation parameter, s. So we think this feature changes mechanical characteristic of Truss Core Panel. In this paper, we examined formability of Truss Core Panel according to Truncation parameter, k and Separation parameter, s. through the dynamic FEM simulation. As a result, Relation between Thickness Reduction and Truncation parameter, k became nonlinear in certain Separation parameter, s. And we examined strength characteristic of Truss Core Panel after Press Forming. So this panel has the effect of work hardening. As a result, Relation between Mean Load cf Panel and Truncation parameter, k became almost linear despite Separation parameter, s. In conclusion we showed Formability and Strength Characteristic affer Press Forming do not always relate in the same condition.

記述言語：日本語  

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.

DOI： 10.1299/kikaia.73.1302

記述言語：日本語  

By allowing elastic deformation in truss members, it is investigated whether or not shape-changable/variable geometry truss structure can be designed based on the origami models of foldable cylindrical and conical shells. Stability (or instability) and statically determinate(or indeterminate) conditions in truss structures, whose nodes consists of 6 members are examined under conditions with both rigid members and elastic members. It is exemplified that foldable/deployable truss structures can be designed when members are elastic.

記述言語：日本語  

Today, we need more lightweight and more high stiffness panels, because of environment concern. Especially this demand is strong for automobile vehicles. Here we examine the application possibility to the door structure for the side collision of vehicles etc., paying attention to the Truss Core Panel, invented by Nojima based on "filling theory". Then, we evaluate its bending characteristic through the dynamic non-linear FEM simulation. And we select design variables of Truss Core Panel to examine the sufficiency of its bending characteristic. In this research, three conclusions are obtained as follows; 1) The evaluation value becomes high by making the "flat rate gamma" small 2) The evaluation value also becomes high as "triangular pyramid cutting" length becomes large. 3) If panel board thickness becomes 60&#37; or less, the evaluation value greatly down. Thus, it is important to calculate the optimal value considering both of "formulability and bending characteristic" for its utilization .

記述言語：日本語  

By processing triangle or square pyramid shaped indents on a flat sheet following regular plane tiling patterns, panels with periodical indents are manufactured. By setting a panel piece (as top panel) on reversed one (as bottom one), and gluing them at the apexes of pyramids to nodal points of the tiling patterns of bottom panel, highly rigid core panels are newly developed. By analyzing mechanical property of these core panels with experiments and numerical simulations, it is clarified that surface patterns affect panel rigidity, and they are able to compete with honeycomb at the point of specific rigidity

記述言語：日本語  

Origami Modeling of Functional and 3D Structures

記述言語：英語  

By processing triangle or square pyramid shaped indents on a flat sheet following regular plane tiling patterns, panels with periodical indents are manufactured. By setting this panel (as top panel) on reversed one (as bottom panel), and gluing them at the apexes of pyramids to nodal points of the tiling patterns of bottom panel, highly rigid core panels are newly developed. The basic model named "dia-core" corresponds to the space filling models by two tetrahedra and one octahedron. Besides, varying the geometric patterns which appear on their surfaces, various modified models are devised. This pattern variation is known as Archimedean plane tiling in geometry.

記述言語：日本語  

By processing triangle or square pyramid shaped indents on a flat sheet following regular plane tiling patterns, panels with periodical indents are manufactured. By setting this panel (as top panel) on reversed one (as bottom panel), and gluing them at the apexes of pyramids to nodal points of the tiling patterns of bottom panel, highly rigid core panels are newly developed. The basic model named "dia-core" corresponds to the space filling models by two tetrahedra and one octahedron. Besides, varying the geometric patterns which appear on their surfaces, various modified models are devised. This pattern variation is known as Archimedean plane tiling in geometry.

記述言語：英語   掲載種別：研究論文（学術雑誌）  

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.

DOI： 10.1299/jsmea.49.38

記述言語：日本語  

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, tube shaped core and curved cores are newly devised.

記述言語：英語  

国名：その他  

Design of a beetle inspired deployable wing

記述言語：日本語  

国名：その他  

Inkjet Printed Speaker

記述言語：英語  

国名：その他  

Demo: Origami robots with flexible printed circuit sheets

記述言語：英語  

国名：その他  

Patterns in Insect Wings

記述言語：英語  

国名：その他  

Folding Patterns in Insect Wings

記述言語：その他  

国名：その他  

記述言語：日本語  

国名：その他  

記述言語：英語  

国名：その他  

記述言語：その他  

国名：その他  

3D structural form creation of earwig fan using the algorithmic design tool

記述言語：その他  

国名：その他  

記述言語：その他  

国名：その他  

記述言語：日本語  

国名：その他  

記述言語：英語  

国名：日本国  

記述言語：英語  

国名：その他  

記述言語：その他  

国名：その他  

記述言語：日本語  

国名：その他  

甲虫後翅の折り畳みを応用した展開構造の開発

記述言語：英語  

国名：その他  

New deployable structures based on an elastic origami model

記述言語：英語  

国名：その他  

Manufacture of arbitrary cross-section composite honeycomb cores based on origami techniques

記述言語：英語  

国名：その他  

Designing of self-deploying origami models using geometrically misaligned crease patterns

記述言語：日本語  

国名：その他  

記述言語：日本語  

国名：その他  

記述言語：英語  

国名：その他  

Elastic wing deployments in beetles and their folding mechanisms

記述言語：日本語  

国名：その他  

折りたたみの科学－昆虫の翅にみる展開・収納メカニズム－

記述言語：英語  

国名：その他  

Design of a 3D wing honeycomb core based on origami techniques

対象：幼稚園以下,　小学生,　中学生,　高校生

種別：セミナー・ワークショップ

対象：社会人・一般,　学術団体,　企業,　市民団体,　行政機関

種別：講演会

対象：社会人・一般,　学術団体,　企業,　市民団体,　行政機関

種別：講演会

対象：社会人・一般,　学術団体,　企業,　市民団体,　行政機関

種別：セミナー・ワークショップ

対象：社会人・一般,　学術団体,　企業,　市民団体,　行政機関

種別：講演会

対象：幼稚園以下,　小学生,　中学生,　高校生

種別：セミナー・ワークショップ

対象：社会人・一般,　学術団体,　企業,　市民団体,　行政機関

種別：講演会

日本経済新聞，2023年1月22日朝刊に掲載された連載「生き物に学ぶ」においてハサミムシの翅の生物模倣工学についての研究が取り上げられた．

2022年9月23日朝刊の科学・医療面「昆虫の構造　技術に生かす」において，ハサミムシの翅の折り畳みに関する研究が紹介された．

NHK Eテレ「ミミクリーズ」，はねをたたむ(初回放送日: 2021/11/8)の監修

NHK Eテレ「ミミクリーズ」，はねをひらく(初回放送日: 2021/2/15)の監修

2020年11月号，付録「ハサミムシペーパークラフト」のデザイン，監修