Ichiro Hagiwara

Meiji University · Graduate School of Advanced Mathematical Sciences

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 bec ome a mighty treasure trove of metamaterial cr...

An origami structure has the advantage of being light yet stiff and expandable. Some expandable structures are already widely available on the market, but although many have attempted to develop a polyethylene terephthalate (PET) bottle that is foldable in the axial direction without bending, such bottles are not yet on the market. The present work...

Bent products have recently been applied widely in various structures. The method of sharp bending has the advantage of producing bent products with a fine appearance. Meanwhile, it has been recently shown that origami forming can be applied as a free manufacturing method that creates a fine appearance using complex folding lines. Sharp bending and...

Current vehicle energy absorbers face two problems during a collision in that there is only a 70% collapse in length and there is a high initial peak load. These problems arise because the presently used energy-absorbing column is primitive from the point of view of origami. We developed a column called the Reversed Spiral Origami Structure (RSO),...

The Japanese traditional fan, which is a form of origami originating in Japan with a folding culture, has a variety of three-dimensional expression that differs from two-dimensional expression. The image painted on the fan deforms when the fan is folded. In this study, we create a digital fan model for clarifying the deformation on the fan face acc...

In the crash collision, the vehicle energy absorbers play an important role in the energy absorbed performance. Current vehicle energy absorbers have two defects during collision, such as only 70 % collapsed in its length and high initial peak load. It is because present energy absorbed column is the most primitive from the point of Origami structu...

We have developed a new truss core panel by origami forming to get the higher aspect ratio than that by multi-stage press molding. Our object is to apply the new origami truss core to the train floor. Whether or not this goal can be achieved depends on whether this new origami truss core with a high aspect ratio has excellent sound insulation chara...

Recently bent products are widely applied into various structures. Sharp bending method in bent products has an advantage of fine appearance. On the other hand, it is newly known that origami forming can be applied to freely manufacturing method as fine appearance based on complex folding lines. Sharp bending and origami forming have a common point...

In order to develop a new crash energy absorb structure, in this paper, we propose a new reverse torsion type origami structure (RTO) and a partial heating torsion method. The RTO can adjust the distribution of crash buckling wrinkles by arranging polygonal lines along the side surface, and can have the property of stably continuing accordion-type...

While proceeding with the examination of Level 3, we came to think that the concept of cooperative control is effective for Level 3. In Level 3, when the system cannot stand, the driver receives Request to Intervene(RtI) from the system. This will be only possible if the system itself understands why it requests RtI to the driver and the system can...

We considered what kind of mathematical science is necessary for the realization of autonomous driving. There are common tasks such as high-speed/precision image processing technology and machine learning technology where causality one is especially important at all levels. For level 3, it is effective to generate models that reproduce the accident...

While proceeding with the examination of Level 3, we came to think that the concept of cooperative control is effective not only for Level 3 but also for all levels. In Level 3, when the system cannot stand, the driver receives Request to Intervene(RtI) from the system. This will be only possible if the system itself understands why it requests RtI...

We have proposed a simulation method for obtaining sound insulation performance with good accuracy using finite element method for elongated acoustic tubes that can be considered as one-dimensional. This is due to the separation of the sound pressures in front of the sound insulation wall between incident waves and reflected waves by Helmholtz's eq...

In recent years, ecology, sustainable, ethical, etc. have been paid attentions. From this aspect, the developing of foldable aluminum beer cans is expected, however it has not been realized yet so far. Here, it is conceivable to use folding characteristics of origami structures such as a reversed spiral structure. A diamond-cut can with the Yoshimu...

For autonomous car it is also effective to use machine learning. It is important for the machine learning to be short calculation time and to get smarter with training. And in several cases, it is mandatory to give causality. It is difficult for CNN(Convolutional neural network) which leads the 3rd AI boom to get smarter with training because it ha...

The Japanese traditional fan, which is a form of origami originating in Japan with a folding culture, has a variety of three-dimensional expression that differs from two-dimensional expression. The image painted on the fan deforms when the fan is folded. In this study, we apply the digital fan model to tow-dimensional photographs and paintings to c...

Various structures and materials have been developed to improve the sound insulation characteristics, and sound insulation experiments using the two-point microphone method etc. are conducted to confirm them. This method requires consideration in setting the positions of the microphones. Even if sound insulation characteristics are obtained, it is...

In the case of automobiles, the high initial peak force value sometimes causes harm to the occupants. In the case of a rockfall guard fence, the rope that receives it on the first surface and converts it in the axial direction of the pillar will be cut. The most efficient way to absorb energy in a car collision or kinetic energy of falling rocks is...

If the octet truss core, which is a space filling structure of half regular octahedrons and regular tetrahedrons, has excellent sound insulation characteristics, the possibility of using the octet truss core is sufficiently widened. From this fact, we have studied to obtain sound insulation characteristics of the flat plate and the plate with singl...

Various structures and materials have been developed to improve the sound insulation, and a lot of experiments have been conducted to verify these things. For reason that this method is time-consuming, a simulation using finite element method for a one-dimensional long and narrow acoustic tube has been proposed. However, the calculation result does...

In recent years, ecology, sustainable, ethical, etc. have been paid attentions. From this aspect, the existence of foldable aluminum beer cans is expected, however it has not been realized yet so far. Here, it is conceivable to use folding characteristics of origami structures such as a reversed spiral structure. A diamond-cut can with the Yoshimur...

In the crash collision, the vehicle energy absorbers play an important role in the energy absorbed performance. Because vehicle energy absorbers are hollow columns by weight reduction, they are easily bent. To prevent bending, beads such as notch are placed properly on the column. However, such beads make the reaction force smaller and the collisio...

Origami art has found numerous engineering applications. Many studies show that folding structures are the source of the desired system characteristics. In this article, we discuss the design of a beach umbrella based on the principles of origami and the study of its optical and mechanical properties. The main requirements for the designed model ar...

Optimizing the conversion of solar energy to electricity is central to the world’s future energy economy. Solar panels installations require measuring the total area of the roof and any areas on the roof that may account for gaps due to vents, pipes, roof fixtures, or tree shading. There are several options for measuring roofs (e.g., climbing the r...

Current vehicle energy absorbers have two defects during collision, such as only 70 % collapsed in its length and high initial peak load. It is because present energy absorbed column is the most primitive from the point of Origami structure. We developed the column so called Reversed Spiral Origami Structure; RSO which solves these 2 defects. Howev...

The truss core surpasses the honeycomb core depending on the tasks. The height of core is limited by press forming and so on. Therefore, we developed a method by folding mountain / valley lines like origami. The origami forming method has the feature that it can be done from paper to metal by the same method. By examining three-point bending tests,...

The additive 3D printer (hereafter called Add-3D) creates a 3D object with materials being added together layer by layer. Before printing an object, some professional processes are indispensable, such as creating the 3D printable models by computer-aided design (CAD), or 3D scanner, and STL data modification, which are difficult for normal families...

The stability of energy optimal control (EOC) when the hybrid electric vehicle performs self-driving with speed control is verified by simulation and numerical calculation. As for the effects of the dead time of acceleration and velocity feedback, simulation that add dead time stepwise to both feedback results in negligible control error even if th...

Origami, the ancient art of folding a flat-piece of flexible material such as paper into a 3D shape, has attracted the attention of the scientific community. Origami design of 2D crease pattern originally is developed for human. However, in order to receive the folding pleasure, some crease patterns even are difficult to fold by hand. One of the mo...

The truss core surpasses the honeycomb core depending on the tasks. Generally, the height of the core is limited by the press forming and so on. Therefore, we developed an origami forming method by folding mountain / valley lines like origami. The origami forming method has the feature that it can be done from paper to metal by the same method. Thr...

Truss core was originally developed with the aim of being superior in terms of heat resistance and cheap cost compared with the honeycomb core which uses gluing. In the case of metal, the truss core panel is manufactured by press forming, but it was difficult to develop cores with good formability. Although the problem was solved and it was used fo...

Origami structure has two advantages such as light but stiff and foldable & deployable. Developing of foldable pet bottle has been tried by many researchers and engineers as a representative subject of Origami engineering since birth of Origami engineering in 2002. But it has not been realized yet. Here it is again intended for easily foldable pet...

By increasing in quantity of recent delivery, the demand for packing materials increases. However, the transportation of liquor such as sake and wine is accompanied with a risk and so transport companies do not tend to want to keep baggage. Therefore we use the structure called a foldable double box developing originally in this study. We can expec...

It is the original purpose for self-driving level 3 where authority is transferred from system to driver in an emergency that driver is released from fatigue and tension and can use effectively transfer time. To realize this, it is mentioned that the measure for shortening the time from ➀Perception to ④Act execution through ②Understanding the situa...

In this paper, we focus on some aspects of the finite element simulations of robotic paper folding and the reconstruction of models from the origami crease patterns by the robot arms. The paper highlights the simulation problems, which should be solved in developing our recent study in mechanical and geometrical design of the origami-performing rob...

The truss core panel is a composite of double-layer triangular core panels, and has characteristics of high strength and low weight. However, problems of fracturing and a limited forming height arise because of the complex shape of the panel. From research on a hemispherical shape transition mould, we propose a new pyramid transition shape for the...

The front side members of a car play a vital role in energy absorption for improved occupant safety during a crash. The response of side members with a half cut structure was examined with a parameter study. The structural design variables were the number of edges of the polygonal cross section, the spot welding spacing, and the thickness of the th...

Box in Assembly Truss Core Panel (BATCP) has been developed as a cushioning material as a box replacement for honeycomb boards as a part of origami engineering research. The superiority of BATCP as a cushioning material has already been described in detail, so it is omitted. ATCP consists of tetrahedron and octahedron half, filling them in a box. i...

Current vehicle energy absorbers have two defects during collision, such as failing to achieve an ideal collapse (only 70 % collapsed in its length) and high initial peak load. It is because present energy absorbed column is the most primitive from the point of Origami structure. We developed the column so called Reversed Spiral Origami Structure;...

Origami engineering is a subject that is concerned with various science technologies based on the social requirements by using the lowest cost for the maximum efficient products. One of the most important origami engineering is the energy absorbing problem. The existing disaster prevention fence of absorbing energy is mostly used by nets and ropes....

Origami, the ancient art of folding a flat-piece of flexible material such as paper into a 3D shape, has attracted the attention of the scientific community. Origami design of 2D crease pattern originally is developed for human. However, in order to receive the folding pleasure, some crease patterns even are difficult to fold by hand. One of the mo...

It is indispensable to use simulation of computer science for industrialization of origami structure. Origami structure is more complicated than other structures, that is why we have difficulty in model creation. However, we can obtain mesh relatively easily by mesh generation function provided in finite element method softwares which should be cal...

The ride comfort evaluation is currently done for a driver, and in the future with realization of automatic driving, the evaluation will be carried out for crew members. In this study, we aim at predicting crew members' states from their expressions in order to optimize their ride comfort evaluation. As the first report, we measured a state of a pa...

As a representative method of model surface, triangular mesh, which commonly has the stereo lithography (STL) format, has recently been widely applied in the CAD/CAE/CAM field, due to its superior robustness and high efficiency in tool-path generation. 3D product model optimization is of great importance for improvement of function, reduction of pr...

The earthquake is a natural disaster which is irresistible and hard to forecast. In the earthquakes, the helmets play an important role in protecting the head of people. The traditional helmets have some disadvantages of storability. Even very few foldable helmets have been designed, the price of them are expensive. In order to overcome these disad...

There are many commercial foldable products in our daily life, foldable umbrellas and airbags for cars are typical examples. These are made of materials which are thin and flexible; however, it is not easy to find such convenient foldable products made of thick and rigid materials, even for cardboard boxes. The main purpose of this paper is to prop...

In this work, we present a strategy to design and construct 3D shape paper models that can be automatically folded and glued using a robotic machine. Here, we use concepts of “kirigami”, that is a combination of folding and cutting paper, and “norigami”, that combines folding with gluing of the paper. A software was developed in order to create cre...

In this paper, a novel vibration isolator based on a foldable cylinder with a torsional buckling pattern, which is also called Kresling's pattern, is proposed, and the performance of the proposed isolator in terms of preventing structural vibration is numerically evaluated. It is known that foldable cylinders with a torsional buckling pattern provi...

Soft-computing forms the basis of a considerable amount of machine learning techniques which deals with imprecision, uncertainty, partial truth, and approximation to achieve practicability, robustness and low solution cost. This paper describes an application developed to understand what means a picture (portrait) to be Iyashi. The neuro-fuzzy quan...

In order to produce the origami-based foldable structures, designers have to determine the industrial material type, the geometry of structures and dimensions etc. These structures may be deformed in proportion to the load at the first step, and show the property of spring. Next step, the deformation will become non-linear conduct. However, deforma...

The earthquake is natural disaster which is irresistible and hard to forecast. In the earthquake, the helmets play an important role in protecting the head of people. The traditional helmets have some disadvantages of storability. Though very few foldable helmets have been designed, the price of those are expensive. In order to overcome these disad...

As part of house design and selling procedures, the option to create and observe the final result using a scale model is essential to analyze and make important decisions about the shape of the house, or structural modifications. In this work, we developed a methodology able to create a three-dimensional (3D) house-model using its elevation views (...

Origami structure has two major characteristics; light and rigid, foldable and deployable. And so, it is used effectively in industry. If we can fold empty cans and plastic bottles after drinking, it is possible to consider new industrialization, but it has not been put to practical use yet. Recently, Tachi-Miura 's Polyhedron is drawing attention...

The existing collision energy absorber of vehicle collapse ideally only 70% deformation and the high initial peak load is a problem. So our group has paid attention to the reversed spiral cylindrical origami structure (RSC) to overcome these two problems, but the energy absorption amount of RSC was low. However, after optimization analysis, the ene...

Origami is a traditional Japanese craft that is based on the folding of the designed structure and can be widely used by industry. Origami folding is not a difficult task for human hands; however, folding by robot hands is such a challenge. In this paper, we suggest a novel approach for designing the origami-performing robotic systems. The main ide...

This paper introduces the basics of origami-based foldable structure designs and gives examples of practical applications using these structures for readers who are not familiar with this research field. First, the mathematics associated with origami-based foldable models, such as the conditions to be flat-foldable around a single vertex (Kawasaki’...

We can see many products with the foldable and deployable function of origami in life, such as solar cell, solar panel and so on. Until now, Nojima has invented a lot of excellent foldable and deployable structures, among which the reversed spiral cylindrical structure (RSC) was parametrically expressed by Hagiwara et al.. The structural shapes of...

Origami structures are now applied more and more in industry with the advantages of enough stiffness to support weight, but can be folded flat for shipping or storage. Not only ordinary paper with small thickness 0.1mm, but also special paper materials such as cardboard or coated paper, which thickness is bigger (1–2mm) is used for forming origami...

Creating complex 3D objects from a flat sheet of material using origami folding techniques has attracted attention in science and engineering. Here, we introduce the concept of “Norigami” that is a mixture of three Japanese words: “Nori” that means glue, “Ori” that means Folding, and “Kami”/“Gami” that means paper. Using traditional origami, spheri...

This paper introduces a method for the automatic conversion of the 3D mesh models into a set of the 2D patterns for producing physical copy-models. We consider the models that can be segmented into the near-developable parts. Each part is regenerated into the 2D patterns by decomposing it into a set of triangle strips and mapping them onto the 2D p...

Nowadays, self-protection is a very important issue for everyone, and it is an urgent request to invent a helmet which is convenient for storage, for example, the one which is not disturbing to pass through the passages between desks and enough small to put in lockers in class room. There are many foldable helmets in market, but they can be folded...

Reverse spiral origami structure is one of the most representative origami structures that can absorb energy effectively in vehicle crash. Since the structure has a complexed cross section, the hydroforming process is complicated and parameters are difficult to be controlled. In this paper, we used response surface method to optimize the parameters...

Creating complex spatial objects from a flat sheet of material using origami-folding techniques has attracted attention in science and engineering. It is extremely difficult to introduce highly versatile automation using machines to handle deformable objects such as a flat sheet of paper. This work proposes two machines for paper manipulations base...

Two pairing origami structures have been attracting attention as a three-dimensional version of the Miura-Ori. Here, as a typical example, we treat Nojima polyhedron (NP) and Tachi-Miura polyhedron (TMP) to check the validity as an energy-absorbing material. Effectiveness as an energy absorber of reversed spiral cylindrical origami structure (RSC);...

Previously for the analysis of Iyashi structure, the mapping function which is obtained from fixtures of facial expressions to the judge by the subject whether the data is healed or not to the subject. This accuracy is determined by the type of inputs and it is not always the general way to select the input data. In recent years, deep learning has...

Recent advances in simulation in science and engineering are focusing on automatic measuring of human-feelings about a product design by using Kansei Engineering words. Iyashi is a Japanese word used to describe a peculiar phenomenon that is mentally soothing, but is yet to be clearly defined. This paper explores the analysis of Electro Encephalogr...

Sandwich panels, for example, honeycomb structure, are widely used in various stages because they are lightweight and have high stiffness. Recently, an origami structure called truss core panel (TCP) has become known as a lightweight structure that has the same bending stiffness and better aspects in shear strength and in-plane compressive load tha...

A tsunami is caused by a large coastal earthquake. We devise the foldable tsunami pod on which evacuees can get, when tsunami is approaching. The 3D model for the foldable ellipsoid body is generated by FEM software “LS-PREPOST”. We perform a numerical simulation, and confirm the safety by von Mises equivalent stress and Head Injury Criterion (HIC)...

People rapidly form impressions from facial appearance, and these impressions affect social decisions. Data-driven, computational models are the best available tools for identifying the source of such impressions. However, the computational models cannot be accepted unless they have passed the tests of validation to ascertain their credibility. In...

Although honeycomb panel is widely used in various stages, its adhesive for gluing honeycomb core and plate may burn by fire, leading to the requirement of another lightweight and high stiffness panel. Recently, an Origami structure called Truss Core Panel (TCP) is known as a lightweight structure that has equivalent bending stiffness as honeycomb...

In robotics, one of the most difficult task is to perform a precisely and fast movement of a robotic arm. For paper-folding robots, it is still extremely difficult to execute the required manipulations of the paper mainly because the difficulties in modeling and control of the paper. In this paper two control models are proposed to solve this probl...

In this paper, a new vibration isolator using origami-based foldable structures is proposed and the performance of the isolator is numerically evaluated to prevent structural vibration. Next, the prototype of the isolator is introduced. It has been known that the origami-based foldable structures based on torsional buckling pattern provide the bist...

Recently, a new manufacturing method called Origami-forming is developed, based on traditional Origami approach. In particular, the new method follows the same steps as Origami, applying for wider rank of material (soft and hard material such as aluminum, high tensile steel, etc), and folding by a reconfigurable robot system. This method is suitabl...