In this report, we propose a technology to automatically detect design problems of the product from user observation videos. In the proposed method, we attach color markers to necessary portions of a user and a product. Then we identify the coordinates of the markers in user observation videos by image analysis and color detection, compare the coordinates among markers qualitatively in every frame of the videos, and classify and encode user's postures in all frames of the videos. Through N-gram analysis of qualitative posture sequences in the video, we classify and encode the user's behavior patterns as specific sequences of qualitative postures. We assume that the behavior patterns which frequently appear only when the user does not understand the usage of the product should possibly indicate some design problem such as incomprehensibility or difficulty for using. By conduction some experiments to detect such behavior patterns from user observation videos, we show the effectiveness of the proposed method.

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Reverse engineering is typically carried out in a procedure which uses a special scanning device such as a 3D laser scanner. However, this typical procedure is not always suitable because of several reasons; for example, the object to be scanned needs to be suitable in the scanning stage of the device, which is not always possible; the scanning device is not always available because of the high cost of the introduction. Therefore, an alternative method for general users is expected. This study focuses on an image-based 3D shape reconstruction and measurement method using a typical digital camera. First, this paper describes the conventional reverse engineering method, followed by the image-based 3D shape reconstruction method proposed in this study. Then this paper shows the experimental results of measurements based on the reconstructed shape, and discusses the feasibility of the proposed method.

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In order to establish a new method for ergonomic design of a computer mouse, movements of joints and tip of forefinger during operating the mouse was analyzed. Based on the analysis and numerical computation method, a supporting software for deciding size and location of the mouse wheel was developed by using Visual C++ and OpenGL. Results of calculation and simulation agreed well with those of the experiments. Effectiveness of the developed software was confirmed.

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A current four-wheel walking assist device described the research and development of three-wheel type walking assist device. The turn is good. And, it reports on the result of review of the approach to get operativeness without the sense of incompatibility to which the road resistance becomes empty in the lightness when the small walking assist device secures the safety of walking is developed.

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In conceptual design phase, if designers are much more conscious of design objectives, they won't come up with various ideas about new product. On the other hand, using brainstorming allow to get various ideas, but to get a lot of unavailable ideas together. In this study, to support generating various and effective ideas in conceptual design, we propose two conceptual design support methods based on Data Envelopment Analysis and Analytic Hierarchy Process. The former is the method using several evaluation values to fill the gap of palate frontier and creating hierarchy graphs. The latter is method establishing a prioritized list of all ideas by paired comparison. Various information is given to the designer from these graphs when they conceive new ideas. We verified which technique is effective to obtain new ideas with high evaluation by comparing these two methods. The result shows that the proposed method using hierarchy graphs is more efficient than the other way using the prioritization graph.

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Robots are expected to join in not only a great success in the industrial field but a public and a home places. However, in order to accept robots socially, when our life spaces are shared with them, it is essential that a safety is fully obtainable. In this paper, for the development of a safety and a relief biped robot, new design concept is created by applying the CDSS (Creative and inventive Design Support System). Moreover, demands of a safety and a relief for this robot are solved not as "Problem Solving by Trade-Off", but as "Contradiction Solving" by using CDSS. Therefore, we reported this creative and inventive thinking process and experiment to validate proposed idea by using simple prototype models.

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On V-shaped process of model based development, from upper process to lower process, methods on decomposition of design information model has not been established. This paper proposes iterative design process for refinement of design information model and stepwise verification and validation(V&V) are enforced using DSM (Dependency Structure Matrix) which expresses design information model of two layer. In this paper relation between SysML diagram, diagram element and activities to create SysML models are described on DSM and analyzed to refine models and enforce V&V process.

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In the development of complex mechatronics products, It is requested to pursue its add-value, are increasingly being required to develop a complex and delicate features. But the failures of high-functional feature are found in the prototype-stage, and experts try to solution with "Suriawase", it has led to an increase in rework effort. The authors predict that there are insufficient validation of behavior on design phase, so failure has become apparent in the prototype stage. In order to design high-quality behavior, the authors propose a design approach that integrates object-oriented analysis and parameters constraints. In this approach, the authors adopt the phase diagram to analyze the states and make clear the points that should be verified.

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In a system design, two big subjects when optimizing a design variable occur. One is that multiple-purpose optimization is required since an objective function is not one. Another is that design space becomes huge since there are many design variables, and solution search becomes difficult. Then, the optimization of a hierarchical type that divides design space and performs solution search becomes indispensable. However, the technique of performing only search of the solution that satisfies restrictions conditions, and the technique of combining the multiple-purpose optimal solution that divided the design into the partial problem, which does not have dependence mutually, are only proposed. So, by this research, since examination fundamental about the multiple-purpose optimization technique applicable also to a dependable partial problem was performed and the possibility was clarified, it reports.

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In this paper, we introduce the outline of the conic roller screw mechanism, a new device for converting rotary motion to linear motion, and report on its infinitesimal slip design. The mechanism achieves higher durability than that of ball screws by reducing Hertzian stress on rolling contact and also maintains high mechanical efficiency by minimizing partial slip on the contact line. Partial slip minimizing theory and method for accurate estimation of slip velocity are described in detail. Results of efficiency estimation shows that the roller screw mechanism has good efficiency comparable to ball screws.

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In the multi-cabin elevator (MCE), multiple cabins (cars) move in the shafts. In MCE, a special control algorithm is necessary for avoiding the conflict between cabins. We have presented the group control algorithm with non-overlapping service zones for MCE. In this algorithm, each cabin has the non-overlapping operating zone and therefore, the conflict between cabins can be avoided perfectly. On the other hand, its performance strongly depends on the initial service zones. In this study, genetic algorithm is applied to the optimization of the service zones of cabins. The numerical results show that the average operation time of the group control algorithm with optimized service zones is smaller than that of the non-optimized service zones except for high-load case.

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In this study, the shooting performance of the badminton machine with the two rollers developed by the author is examined. Finite element models of a feather shuttlecock and the badminton machine with two rollers are made, and the shot simulations proceed with the moving behavior and contact stress of the shuttlecock. The coefficient of friction is examined from the surfaces in contact with the shuttlecock and the roller in the analysis. From the analysis, it is shown that the roller with a small diameter attains the lower speed of the shuttlecock than the other rollers for every shot. The taper angles of the roller edge and the insert height of the shuttlecock are optimized that the shuttlecock speeds are maximized by the shooting simulation and the response surface approach. The validity of the optimum condition is confirmed by the corresponding shot experiments using the two-roller type badminton machine.

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One of the important issues on the Sequential Approximate Optimization (SAO) is the sampling strategy. The sampling strategy for SAO using the Radial Basis Function (RBF) network is proposed in this paper. The proposed sampling strategy consists of three parts, which are called the density function, the boundary function, and random sampling. In order to add the new sampling points effectively, the density function and the boundary function are constructed by the RBF network. The objective of the density function is to find the sparse region in the design variable space and is to add the new sampling points in this region. In the constrained optimization problems, at least, one or more constraints will be active. As the result, it is desirable to add the new sampling points on the constraints. The objective of the boundary function is to add the new sampling points on the boundary. In addition, the random sampling is also introduced to spread the search region. The algorithm of proposed sampling strategy is described in detail. Through the numerical examples, the validity is examined.

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In recent years, Machine Learning techniques, such as Support Vector Machine (SVM), Radial Basis Function (RBF) network, and so on, have been widely employed in engineering fields. In particular, the SVM is one of the powerful classifiers. However, the formulation of the SVM is slightly complex. In addition, we have to solve the Quadratic Programming (QP). The Least-Squares Support Vector Machine (LS-SVM) is one of the machine learning techniques. In this paper, the LS-SVM is introduced. In the LS-SVM, equality constraints is considered. Thus, the solution can be obtained by solving a set of linear equations instead of solving QP problem. The extension of the classical SVM to the SVR is more complex because the epsilon insensitive loss function is introduced, while it is very easy to extend the LS-SVM classifier to the regression version.

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In deep drawing, a low blank holder force (BHF) will cause wrinkle, while a high BHF will result in tearing. The Variable Blank Holder Force (VBHF) approach is attractive approach in the industries, and it is important to design the VBHF trajectory. In this paper, sequential approximate optimization (SAO) approach is employed in order to obtain the VBHF trajectory. The objective is taken as the minimization of the deviation of whole thickness. The constraints are quantitatively defined with the Forming Limit Diagram (FLD), in which no wrinkling and tearing can be observed. The design variables are the blank holder force. Constraints in which the wrinkling and tearing are avoided are introduced in this paper, compared with the related past researches. The Radial Basis Function (RBF) network is employed for the response surface. The validity of the VBHF we obtained with SAO is examined through the numerical simulation.

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In this research, modified PARSEC airfoil representations are developed and they are investigated by the design exploration of airfoils for the Mars airplane. The existent PARSEC airfoil representation method is useful for the aerodynamic optimization and the knowledge discovery, because the original PARSEC airfoil is parameterized based on the aerodynamic theory. In this method, designer can directly define airfoil's parameters, the leading edge radius, the maximum thickness, the maximum camber, and so on, However, the original PARSEC representation cannot use for not subsonic flow (supersonic flow, low Reynolds number flow), because it was parameterized in consideration of a subsonic wing. To solve the several airfoil design problem, modified representation method is constructed and its design performance is investigated by solving multi-objective design problem. This study employs Genetic Algorithm (GA) for exploration of the multi-objective problem. Flowfield is solved by the structured Navier-Stokes solver with Baldwin-Lomax turbulent model. According to these results, the modified airfoil representation method can solve the design problem under the Martian atmosphere better than the original method.

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Teamology is established by Prof. Wilde for building a creative team for projects. It is based on results of questionnaires of MBTI which is basically developed for personal enlightenment, in US, in Japan, because of cultural difference, it is not clear to give type identification by using MBTI. Therefore, we introduce more suitable questionnaires for Japanese, and we would like to establish Japanese. In this study, we use a method called "BigFive". We have applied it to the same persons who had already gone through MBTI and compared the results and examine the effectiveness, of the proposed method.

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Teamology is established by Prof. Wilde to make creative teams in project teams. As a first step, it needs questionnaires to characterize personality for each member who joins the projects. Assume in academic project based learning teams, a number of students join and we are going to make several teams. Each team should have the same potential if and only if we can make every team as that. In order to create these teams, we need to quantify students' characters, and we need to formalize them to meet the guideline of Teamology. In this study, we are going to make multi-objective optimization formulation of Teamology, and show an example of team making by using a genetic optimization algorithms with data that was taken PBL course in Kagawa University.

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With the development of excellent software in optimization, there is more and more wished to use these techniques and make epoch developments in their products. However, most of us know that it costs a lot of time and costs to carry out optimization, because it needs to repeat simulations for the number of times. Therefore, most engineers would like to make mathematical models of design problems just enough to express their needs priori to optimization. Let us call these models as light models, in this paper. However, it is very difficult to make a proper light model in the first trial. Recent optimization will find the global solution, so that it will find some modeling miss and lead light model to some strange results. Such phenomenon is not a fault of optimization, but of the light model. We have to revise the light model but it is way difficult to make it rationally with the information we have had from the light model. We have to think of appropriate values of existed constraints, we have to think of new functions for constraints, and so on. It is almost hopeless to revise the light model at one time. The best thing that we can hope for is to give up the light model and make models complex to express the situation of the products. If we do not know proper values for constraints, treat them as objective functions and just go through trade-off analysis to have their relationships information, so that we can give appropriate values. In this sense, it is very important to make models in multi-objective optimization. In multi-objective optimization, it is quite important to carry out trade-off analysis and which might be a key to find epoch design. We had developed approximate multi-objective optimization method, which is composed by satisficing method, convolute radial basis function network and recommendation of new design variables. In satisficing method, we can handle trade-off analysis much easier than weighting methods. However, scalar function composed by satisficing method is not smooth when it gets close to Pareto solution that is indicated by designer's requirement. Therefore, it is difficult even for convolute RBF to compose better approximate function although we have better approximation for each objective function. In weighting method, it is quite difficult to give proper weights for designer's requirement. In approximate optimization, fortunately we have a number of data sets. Thus, it is possible to optimize weights which meet for aspiration level in satisficing method. Then, we can have smooth and better approximation for scalar function. In this paper, we are going to show effectiveness of the proposed method through demonstration of numerical examples.

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These days robust design has become more and more important to raise reliability in the products under many kinds of impression, including human errors, modeling errors and so on. In the past, robust design only tries to obtain the robust design variables that have less sensitivity with quasi-optimum solutions. Recently, many researchers try to design not only of design variable's value but also to its deviations. Which means that robust design tries to have wider range of design variables and still keeps robustness in the design. For the simplicity of calculation, most of them assume independence of design variables, thus, the ranges are determined by their upper and lower bound. However, in the real design almost every design variables are not independent with the influence of constraints. In this study, we will newly propose the method that can consider relationships of design variables, something like correlation of design variables. We will show the effectiveness of the method by some numerical examples.

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The corrugated cardboard is widely used for packing in the transportation. Therefore, the technology that minimizes various transportation accidents is necessary. Especially, the accidents by the impact occupies the more than the half of the accidents. There are many researches that evaluates the maximal acceleration of the corrugated cardboard under the impact. However, because the maximal acceleration is not necessarily corresponding to the damage of contents, it is difficult to evaluate the impact of the corrugated cardboard only by the maximal acceleration. Also the place to measure is the center of the ground side but it is not discussed about the measuring place. In this paper, impact force is applied by a free fall test by a guide rail to drop it straight to the ground. The ID acceleration sensor, are glued in several place to make clear the difference between the measured place. From the experiment, we considered impact energy and the maximal acceleration. In addition, we made an analytical model of the corrugated cardboard to analysis to identity the damage. As a result, strain energy has a correspondence between the experiment and the analysis and the maximal acceleration didn't have it. So, the utility of the strain energy was able to be shown as a method of evaluating the impact using FEM. Through this result, we watched how the energy spread and found out the center of the ground side and the wall side has a high energy when it's impacted and when a few second pasts the wall side still has a high energy because of the vibration of the cardboard. To find out the relation between the data from the corrugated cardboard and the contents. As a result, the maximal acceleration has a strong relation between the center of the ground side and the energy has a strong relation between the middle of the center and the corner. Finally, we also considered HIC36 to evaluate the impact.

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Aluminum alloy plates are commonly used in automobile, train, aircraft and so on where lightweight is required. However, lower costs and lighter weight materials are demanded. In order to satisfy the demand for lightweight without changing the material, it is necessary to raise the second moment of area to increase stiffness. The purpose of this study is creating isotropic thin shell structures to increase the stiffness of aluminum alloy plates. In this paper, shell structures which have the large second moment of area in arbitrary cross sectional dimensions were developed. FEM results and experimental results indicated that the developed shell structures made the weight of plates less than half under equivalent stiffness condition.

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Grammatical evolution (GE) is a kind of new evolutionary algorithms. It is related to the idea of genetic programming in that the objective is to find an executable program or program fragment that will achieve a good fitness value for the given objective function to be minimized. Therefore, the search algorithm of GE is very similar to Genetic algorithm (GA) except for the translation rules. In the GE, the translation rules from genotype (bit string) to phenotype (function or program) are defined according to the Backus-Naur form (BNF). The rules are applied for estimating fitness functions. In this study, an original GE and three improved algorithms are applied for predicting the constitutive equation in the plane strain state. The numerical results show the convergence speed of the improved algorithm is faster than the original GE.

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This paper proposes a method of inverse analysis for identification of an impact load based on the data selection approach. Taking the dynamic behavior of structure under the impact load is comparatively easy if many sensors and high precision measuring devices are available. On the other hand, if the dynamic behavior can be identified by a few strain data with lower accuracy, the method has advantages to measuring cost and efficiency. In this study, the application of the proposed inverse analysis method is shown in the designing of the new type of the pitching plaything. In the proposed method, the fuzzy clustering is used for selecting and picking up the strain data containing errors for the neural network learning. As a result, it is shown that the proposed method has an advantage on the inverse analysis for some margin of errors.

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Level set-based shape optimization methods are proposed as new type of structural optimization method and we proposed a new topology optimization method based on the level set method and concept of the phase field method. This paper proposes a level set-based topology optimization method with an uniform cross-section surface constraint based on our proposed level set-based topology optimization method. First, basic details of the level set-based topology optimization method are briefly discussed. Next, based on the regularization method, the topology optimization method considering a uniform cross-section surface constraint is formulated. Finally, three-dimensional example is provided to confirm the validity and utility of the proposed topology optimization method.

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In this paper, first, a topology optimization problem is formulated based on the level set method and a method for regularizing the optimization problem by the Tikhonov regularization method is explained. The reaction-diffusion equation that updates the level set function is then derived and an optimization algorithm, which uses the finite element method to solve the equilibrium equations and the reaction-diffusion equation when updating the level set function, is constructed. Next, the implementation of combining the level set-based topology optimization and the finite cover method is explained. Finally, a numerical examples is provided to demonstrate the effectiveness of the proposed method of topology optimization for minimum mean compliance problems.

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The topology optimization method is one of the most flexible structural optimization method that allows not only shape changes but also topological changes during the optimization process. However, due to its high flexibility, the utility of topology optimization results is often spoiled by a preponderance of impractical designs such as structures contains many grayscales. To mitigate this problem, a type of structural optimization method using the level set boundary expression has been proposed, in which the boundary of the optimal configuration are implicitly represented using the level set function. This paper proposes a topology optimization based on the level set method using mathematical programming. In the proposed method, the level set function is updated using a mathematical programming. The optimization problem which has many constraint functionals can be easily formulated using the proposed method. We apply it to the minimum mean compliance problem to verify the proposed method.

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In this paper we present a free-form optimization method for the optimum design of shell structures in order to control the static deformed shape to a desired one. As an objective functional, we introduced a squared deformed shape error norm on the prescribed surface. It is assumed that the shell is varied in the normal direction to the surface and the thickness is constant. A non-parametric shape optimization problem with a volume constraint is formulated, and the shape gradient function is theoretically derived. The free-form optimization method is applied to determine the optimal smooth shell while minimizing the objective functional. The calculated results show the effectiveness of the proposed method for the optimal free-form design of the shell structure with a desired deformed shape.

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In this paper, we present a shape optimization method with pyramid shape basis vectors for creating beads on shell structures. The volume is set as the objective function, and is minimized under multiple behavioral constraints involving compliance, maximum von Mises stress, elastic bucking load and natural frequency. The pyramid shape basis vectors are created using the small lattice domains so as to express the local shape variation in the normal direction on the surface. The morphing technique is employed to vary the domain consisting of the several finite elements. The global shape involving the local embossments is determined by this method. This method is applied to a cylindrical roof problem. The results for a cylindrical roof problem show the validity of this method for creating optimal beads on shell structures.

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This paper presents a numerical analysis method for shape optimization for mean compliance minimization on thermoelastic fields. The mean compliance minimization problem means a stiffness maximization problem for the shape optimization. The mean compliance minimization problem on the thermoelastic fields is formulated on volume constraint condition. The shape gradient of the shape optimization problems is derived theoretically using the adjoint variable method, the Lagrange multiplier method and the formulae of the material derivative. Reshaping is accomplished using a traction method that was proposed as a solution to shape optimization problems. In addition, a new numerical procedure for the shape optimization is proposed. The validity of the proposed method is confirmed based on the results of 2D numerical analysis.

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This paper has studied thread shapes of a cap of aluminum beverage bottle, which can be easily opened. Firstly, both the tightening torque and loosening torque of the well-used triangle thread and square thread are calculated. After that, a new thread shape, whose tightening torque and loosening torque are much smaller than those of the conventional threads, is proposed. Then, a simulation of existing aluminum bottle model is implemented by using a commercial software ANSYS. Moreover, three kinds of new thread shape models with different mountain angles are suggested to perform simulations and the opening torques of these three models are compared with each other. The comparison among the opening torques of three thread models with the theoretical values of the triangle screw and the square screw are made and discussed. Finally, it is found that the proposed new thread shape model shows a lower opening torque.

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To improve the collision safety of compatibility performance of big-size cars such as Trucks and Pickups, the installation of Secondary Energy Absorbing Structure (SEAS) in front of vehicle body is proposed. To evaluate the influence of design parameters on the impact behavior and response for the better design of SEAS, the collision phenomena between vehicle and Full Width Deformable Barrier (FWDB) has been simulated by using CAE tool Ls-Dyna. Finally, a new model of SEAS that has a better performance both in compatibility and lightweight will be proposed based on the technique of optimum design.

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Serious injured parts of pedestrian include head, chest and legs, when hit by an automobile frontal collision. Lower absorber equipped under the front bumper is one of the effective devices for the suppression of serious leg damage. In this paper, it is proposed more effective device called active lower absorber, which moves just before or shortly after the impact to suppress knee injury without the increase of other criteria values by adjusting the design parameters of timing of activation and the absorber motion. The response surfaces of four injury criteria of multi-objective design problem are constructed based on the crash analysis by LS-Dyna and design of experiment. The Pareto-optimum solutions are found by the ε-constraint method, and categorized by the self organized mapping method(SOM).

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The recent improvements in safety design of Heavy Goods Vehicles (HGV) against pedestrian shows positive direction in reducing fatality and serious injury during collision. Despite continuing improvements worldwide, the research of passive system of HGV is not heavily studied due to its nature of aggressive front structure and a higher possibility of pedestrian run over. This paper addresses an analysis of a front structure of HGV for pedestrian safety. A preliminary analysis of pedestrian accident using MADYMO multi-body simulation is conducted to show the design potential. The results highlighted will be important for future design implementation.

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This research is aimed to study on effects of Blank Holder Gap (BHG) on deep drawability, that has been investigated for a cylindrical cup deep drawing process from square blank shape. The BHG is an effective way to control material flow into the die cavity during forming process. The effects of BHG on deep drawing of circular cup are studied by using numerical simulation method with commercial code named LS-DYNA. The BHG is defined as a distance between die and blank holder surface (clearance). In this study the BHG is ranging from 1.05 to 1.60 mm when initial blank thickness is 1.00 mm. For failure (wrinkling and tearing) detection of deep drawing process Forming Limit Diagram (FLD) under Swift and Hill's criterion and Wrinkling Limit Diagram (WLD) are used. In order to find out an optimum BHG, and objective function of this research is defined as risk of tearing. From numerical simulation results, the BHG has a great effect on the forming quality of formed product. As ranging of BHG from 1.05 to 1.60 mm, a suitable BHG for deep drawing of circular cup for given tooling and material is tried to design. Moreover, a simple closed-loop algorithm had been developed in order to determine the variable BHF trajectory for constraint BHG during forming process.

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In human activity space, there are obstacles with various sizes and configurations. The purpose of this research is generation of the motion for walking robot in response to the obstacle environment. In this research, generation of the motion for walking robot carry out by the optimization of stepping points and the generation of toe trajectory between every stepping point for the toes. We make the neural networks to generate the stepping points in response to the obstacle recognition. Training data for the neural networks are optimum stepping points based on mechanism of robot model generated by genetic algorithm. The sets of the representative points of obstacle is input data and the sets of stepping points is out put for the trained neural networks. In the case of using the unused training data for input data, the neural network output the optimum stepping points successfully.

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We proposed a new design knowledge management approach called quantity dimension indexing. Although the proposed approach is effective, the design engineering knowledge in actual design activities is described by literal expression. In this paper, we propose automatic indexing method to introduce the proposed approach to actual design activities. For automatic indexing, we create a dictionary of relation between expression and quantity. The design engineering knowledge described by literal expression is automatically indexed by quantity according to the dictionary in order of inclusive relation among expressions of the dictionary. Morphological analysis result is also considered. By automatically indexing a fault tree example based on actual design activities in a company, the possible feasibility of automatic technique is indicated.

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In this paper, the authors propose computerized support for fault tree analysis (FTA). When a designer finds or encounters a problem during a product design and development process, an effective way of ensuring the function of product is to identify all the possible causes of the problem by FTA and fix them. Although FTA is an effective method, it is not easy for a designer to construct a complete fault tree without any misunderstanding or oversight. To solve this problem, the authors propose 2 support methods. One is a new design knowledge management approach called quantity dimension indexing and computerized support for FTA such as the verification of consistency of a fault tree and fault tree construction advice. The other is making of the fault trees based block diagram by computerized support. The former has an effect for FTA support of the machine problem, and the latter has an effect for FTA support of the control/system problem. By analyzing fault tree examples based on actual design activities in a company, the possible feasibility and future promise of the proposed approach are indicated.

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Sharing and understanding the product design, design information and design rationale integrated CAD system is needed for cooperative design. This paper proposed a method to support finding influential relations between parts of design object. First, data structure of influential relation was defined. This data structure is composed of quantity size and unit symbol of attribute/property value, and their relation. Then, a method to extract influential relation from product design case database was proposed. Finally, the case-based design support system for derivation of influential relations was developed, and case studies are done by using the system. The result of the case study showed that the proposed system can help designers to find and set the influential relations between parts.

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This research proposes a framework for representing and managing the knowledge involved in engineering analysis modeling for design verification, and discusses formalization and building of knowledge management system. The computation-based design consists of the two phases, engineering analysis for understanding physical phenomena and design verification based on its results. The management format of the engineering analysis modeling process, which is named EAMM (Engineering Analysis Modeling Matrix), is introduced for the first phase. The process structure of design verification and classification of designer's decision making are discussed for the second phase by referring the framework of EAMM. gIBIS (graphical Issue-Based Information System) model, which is a hypertext graph model, is adopted for representing the process structure and the designer's decision makings with multimedia information. This paper also defines an ontology of the engineering analysis modeling knowledge, which is the fundamental of the implementation of the knowledge management framework. A design process of a micro mixing mechanism demonstrates the potential and the promise of a proposed framework.

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We have defined XML schema of polishing case data, which are composed of material specifications, processing conditions, polishing material, machine specifications, and evaluation results. More than one hundreds parameters are dominant. Polishing process is repeated varying the associated parameters until fine surface is obtained. The structure of case data becomes complicated and difficult to handle. We proposed a effective method and examined it through inquiry examples and evaluated it to be applicable to manufacturing supporting method.

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Although such information services as FM-VICS, gas stations, sales at department stores etc., contribute to car drivers for their safety and satisfaction in driving situation, it is hard for them to retrieve such information while driving. It is also difficult to push all such information without any control which should disturb driver's concentration on driving. The authors have been investigating a task-oriented menu, which enables users to search for mobile internet services by what they want to do and not by category. We have built a task model of the mobile users' daily activities and reorganized "contexts" in the model to develop a menu hierarchy from the view point of the task. We have applied the framework to modeling car drivers' activities. Such models indicate when and what kind of information should be provided in the car, which in turn contribute to design ambient interface for the drivers.

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This study is aimed to structure method of supporting design constructing new function by expanding design process. Focusing on concept blending that can create new concept, design process can be expand by taking function blending in process of dividing function. From this standpoint, study of "Composition-based function dividing process" is conducted. Relation of base concepts is factor to create the creative concept in concept blending. However, relation of base functions has not been focused in function blending. Therefore this study proposes the method of deciding base functions that create creative function. Often design is considered as problem solving process. So, from standpoint of problem solving we have proposed relation to create creative. Especially we have found the antonymous relation that is not seen in focusing only blending.

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Considering latent functions on conceptual design stage has become increasingly important from the perspective of product safety and sustainable design. This paper discussed reasoning processes considering latent function on conceptual design stage. First, the function dividing process is explained from a linguistic viewpoint and two function operation types for the function dividing process, which are decomposition-based dividing and causal-connection-based dividing, are introduced. Then, reasoning process considering latent function is formulated on each function operation types. Finally, the function reasoning system was developed and a case study is done by using the system, The case study showed the possibility that the proposed model can help designers to consider latent function on function dividing process.

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This paper proposes a crashworthiness evaluation and optimization method for straight thin-walled columns using simplified models, to alleviate massive computational cost due to a large number of shell elements, required for accurate prediction of nonlinear collapse behavior. The simplified crashworthiness analysis model, developed in this research, is composed of beam and non-linear spring elements. The properties of non-linear spring elements are derived from analytical calculation results of crush mechanism of thin-walled beam. This paper also clarify the design criteria for crashworthiness design optimization problems, and genetic algorithms are used to solve this optimization problem. The proposed optimization method is applied to a numerical example problem and the optimal solution obtained using the simplified analysis model is compared with the result when using a detailed analysis employing shell elements. The optimal solution provided by the simplified analysis model agrees well with the solution based on detailed analysis results.

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In this study, we develop a method for designing an emotional and creative motion that resonates with deep feelings. This study is based on the hypothesis that motion that is beyond ordinary human imagination can produce emotional impressions that resonate with deep feelings. The proposed method involves an analogy with natural objects, the blending of motions, and an emphasis on rhythmic features. In order to design an emotional and creative motion, we attempt to construct a computer system that implements the proposed method. An experiment to verify the effectiveness of the proposed method and the validity of our hypothesis is performed. We compare the impressions produced by the motions that are created in three ways, with an emphasis on their rhythmic features.

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On the basis of tactile interactions, this study aims to capture and analyze users' imaginations on materials. This research also proposes an 'unexpected' new tactile material for design from the viewpoint of tactile interactions. To capture imaginations, we investigated users' tactile interactions in an experiment. The experiment used samples of six common natural and artificial materials, along with the proposed new micro-print-based material. A concept network-based method was employed in two stages to analyze the experimentally obtained verbalized protocols and to identify induced imaginations. This method allowed us to capture and analyze the inexplicit imaginations and associative concepts behind the verbalized protocols. This research found that the feel of materials' tactile naturalness and users' preference to the tested samples are related to their inexplicit imaginations and the complexity of their concept networks. The imagination and concept network of the proposed micro-print material are distinct and different from the existing natural or artificial materials. These findings will provide the basis for employing new analysis tools and facilitate the development of unexpected tactile materials which will enhance the creative ideas for design.

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Recent industries and society have been facing advanced, complicated and uncertain problems. Therefore, we need design science to solve those problems systematically. In this paper, first a design process is modeled as a cycle consisting of four sub-processes: (1) observing a user and finding needs and problems, (2) planning and creating a product to respond to the needs and solve the problems, (3) providing values to a user, and (4) educating and nurturing creative and innovative designer. Based on the design process model, how and where science should contribute is discussed. Along the discussion, some of the related studies by the author are described.

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Robust design enables the products to ensure robust performance in diverse conditions due to increased individuation of user needs and the globalization of markets. In the previous study, a robust design method which evaluates robustness of adjustable mechanism was proposed by using a control factor with adjustable range. However, the method is not applicable to design problems in which more than one control factor with adjustable range are included. In the present study, the previous method was improved to be applicable to more than one control factor with adjustable range. First, a need of improve computational efficiency is identified as a problem to be solved. Second, to improve computational efficiency, a method to decrease computational effort in both searching solution and evaluating robustness are proposed. Specifically, in the proposed method, Genetic Algorithm is applied to search solution, and several adjustable control factors' values used for evaluation of robustness are extracted from their adjustable range. Finally, the proposed method was applied to two numerical examples and effectiveness was confirmed.

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