This paper proposes a new methodology that supports to generate product structure to reduce parts-cost and assembly-cost. It consists of three steps; analyzing structure of the product, extracting applicable elements, supporting to generate solutions to reduce parts-cost and assembly-cost. First step analyzes parts, functions, attributes in order to estimate parts-cost and assembly-cost. Second step extracts applicable elements such as materials, processing methods, assembly directions, joining methods from the data-base. Third step provides the tailored guidelines for creating the solutions to reduce parts-cost and assembly-cost by combining these extracted applicable elements.

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Up front design method for variety (DfV) is effective to minimize model change impact on the total cost of product series. However, DfV is unsuitable to adapt for re-layout of cross-functional module. So, we proposed a collaborative design method by using communication table to visualize the explicit and tacit knowledge of mechanical engineers. This paper shows a design innovation on air-conditioning system about a trade-off design optimization between heat sink layout and device performance by applying a heat pipe. As a result, effectiveness of our proposal method is demonstrated.

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Deployment of a common core to various specifications by adjusting its variable but auxiliary components is an effective implementation method of product variety design. In order to provide a common core that can be used flexibly for various specifications and that can accomplish superior performance on all possible deployments, it is important and indispensable to design and evaluate combinatorial relationships between the primary core and variable auxiliary components and tradeoff among complicated and mutually related factors. This paper discusses application of optimal design paradigm to such a kind of product family design problems and investigates its meaning and outcomes through a case study of heat exchanger design for air-conditioning units.

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This paper discusses possibilities of efficiently designing a family of engineering products such as equipment and machinery, while product family design has been implemented mainly for consumer products. Regarding the differences between consumer products and engineering products, the latter has longer lead time in design and development, and the total number of production units in the latter is fairly smaller than one in the former. By reflecting these differences, we propose a design methodology, which is composed of three phases; strategic identification of common subsystems and adjustable subsystems, anticipatory design of the former subsystems prior to individual orders, and adjustment design of the latter subsystems at respectively individual orders. Among these phases, the second phase is essentially important but complicated. A design method for common subsystems is proposed for this phase based on techniques of mathematical optimization, computational geometry, etc. A design example of product family of centrifugal compressors is briefly demonstrated.

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Product life cycle design has gained more interest in recent years due to growing concern about environmental problems. In general, there exist significant uncertainties (e.g., operating condition, user preference, collection rate etc.) in product life cycle and a design method that is robust and tolerant against these uncertainties should be established. To this end, this paper discusses the uncertainties in product life cycle and evaluates their impact on total performance throughout a whole product life cycle. Based on this discussion, a design method for product life cycle that maximizes its total performance handling these uncertainties is proposed.

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In recent manufacturing technologies, it is very important to satisfy environmental and economical requirements simultaneously. As an answer to the situation, the authors have proposed a new product efficiency index named "total performance index (TPI)" and a procedure of analysis based on the proposed index. The analysis named "total performance analysis (TPA)" is a powerful tool in determining design strategies of "green products". At the same time, manufacturing processes for those green products should be also environmentally benign. In this paper, the authors try to apply the TPA to a series of manufacturing processes. Through the effort, a procedure to evaluate manufacturing processes and to obtain suggestions for process improvement is shown. By using the procedure, designers will become able to determine which process combination is really "eco-efficient".

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As the service sector in economy grows, an evaluation method for service design that increases efficiencies is needed. A service should be evaluated by the viewpoint of service receiver, because it has characteristics such as simultaneous production and consumption. Until now, authors proposed an evaluation function to estimate to what extend a requirement of a service receiver is satisfied. The function is decided by the designer using data about the receiver's expectation and quality of the service. In this report, we classify receivers' requirements in two: service oriented and product oriented. Then, we analyze relationship between the classes of requirements and related functions.

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To reconsider the current mass production paradigm and to make products have more added values largely from knowledge and service contents to compensate volume reduction under the concept of dematerialization, we need new engineering methods to look at services, rather than just functions, called "Service Engineering." In Service Engineering, it is desired to fully satisfy customer demands. However, in order to provide more competitive and innovative services, we need to take into account customers' immediate as well as future needs. This paper aims at proposing a model to express the change in customer demands. The presented model was verified through its application to a practical example.

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This paper has studied factors that affect consumers' feeling when drinking from aluminum beverage bottle, and given a suggestion to method of evaluating drinking ease. Drinking ease of carbonated beverage from three different kinds of opening diameters (φ28, φ33, φ38 ) has been evaluated by using semantic differential (SD) method of Kansei engineering, and the results are compared with that of green tea reported in the previous paper. As a result, major subjects have evaluated that the opening φ33 is easiest to drink than the other opening diameters no matter what kinds of beverage is. And it is found that the factor that affect consumer' feeling are 'ease of adjustment 'and 'flow volume' when drinking from aluminum beverage bottle.

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This paper has investigated effects of the bottle opening size (28, 33, 38mm) and the difference of remaining liquid amount (100, 200, 300ml) on drinking feelings in order to improve the comfort level of consumers when drinking directly from the opening of aluminum bottle. A survey over 30 subjects has been performed, and they have evaluated that the 33mm opening is the best no matter remaining liquid amount. From the result of the factor analysis, it has been found that drinking ease consists of the factor of adjustability and the factor of flow amount. In addition, it has been estimated that the adjustability of the 33mm opening is hard to be affected by liquid amount. Moreover it has become clear from the results of the observation of drinking action that there is appropriate flow amount and angular velocity for subjects.

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This paper has studied factors that affect consumers' feeling in fingers when unscrewing the cap to open an aluminum beverage bottle, and then investigated experimentally and numerically the size of the cap in order to guarantee consumers' openability. At first, the gripping and opening way while rotating the cap by fingers has been determined as the most popular opening way according to a survey of consumers. The grip force and torque have been then measured simultaneously using an experimental bottle equipped with force sensors, and the relationships between the gripping force of fingers and the torque, the dimension and the gripping force of human hands have been investigated.

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This paper describes a new quantification method of a product's emotional quality, which we call kansei quality, with attention paid to its diversity to support the affective design. The customer's sensitivity towards such a quality differs from person to person due to perception gaps and ambiguity. The proposed method helps the designer to grasp such diverse sensitivities of customers. In contrast to the conventional approach that aims to generalize human sensitivity using average results of sensory tests, the proposed method divides an emotional quality based on differences among the customers' sensitivity. We apply the proposed method for designing a machine sound in which the designer deals with the sound quality as a kansei quality. We carry out an impression evaluation experiment on human subjects using existing product sounds. To demonstrate the effectiveness of the method, we compare the proposed method with the conventional approach using experimental results. The comparison results show the advantages of the method, such as the avoidance of meaningless average data caused by canceling out multiple different sensitivities. Based on the proposed method, we developed a prototype system that enables the designer to evaluate the kansei qualities of a created sound without conducting a sensory test.

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In industrial design process, visual imagery and "schema" play important roles to create new product shape. Image movement model as a model of industrial design process based on visual imagery is proposed. Concept of product shape creation system based on image movement model is proposed. Methods for product shape creation system are proposed and implemented.

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To address diversification of customer's sensitivity to perceive a product emotional quality, this paper proposes a design supporting method that quantifies the diverse customers' sensitivities. We apply the proposed method to outward design of cellular phones to show the effectiveness of the method. The result demonstrates that there are multiple viewpoints in an emotional quality expressed by an adjective word depend on personal difference of sensitivity. Using the method, we quantify each emotional scale by applying the quantification theory using design attributes of cell-phone. The analytical result shows that an emotional quality 'luxuriousness' of cellular phone includes two different semantics and evaluation scales. The analysis also demonstrates that the diversification of 'interest' is caused by a difference of a product feature to which customers pay attention. Even if a designer and a customer possess different sensitivity, or even if each customer emphasizes distinct features of a product, the proposed method enables a designer to grasp customers' emotional needs without misunderstanding using the proposed method. Furthermore, it enables a designer to obtain a new viewpoint and a new design clue by diverse emotional quantification scales obtained using the proposed method.

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This paper points out the importance of the role of emotion in reliability engineering. Up to now, reliability of a product has been discussed quantitatively, but the more frequently and the more extensively situations change, the more it becomes difficult to secure reliability based upon a simple mathematical model. As it is the user who understands the current situation better, it would be better to leave the decision and action to the user and to develop the system that helps him understand the situation better and helps him react better. Humans get emotionally upset in the case of emergency and if we could secure emotionally stability, it expected that he could make decisions better.

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The traditional product development was linear because situations did not change often and extensively. But as diversification increases and situations change more often and extensively, product development has to be in the form of continuous prototyping or in the form of a loop as Donald Schon pointed out in his reflective practitioner. Reflective design is needed for the coming years where service is called for.

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In engineering design, innovative design is required. Thinking function of artifacts is necessary to realize such innovative design. Thus function modeling is important. In this study, function reasoning is a kind of operation to generate new function. A new framework is required to realize any kind of function reasoning. For this purpose, we developed relative function framework. The features of this framework are relativity between a function and behaviors and linguistic rules among functional expressions. SVOD frame was proposed for relativity. A case study was done for linguistic rules.

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Authors focus on the process where the designer generates new knowledge from existing knowledge. In this study, this process is called function reasoning. Authors aim to support this process with a computer. Therefore, it is necessary to structurize the relation to which a new function can be generated. In this paper, authors evaluate the artifact from a difference viewpoint that is the basic concept of the inference. And, the function is structurized. The index function used the mode of expression systematically described by using the natural language. As a result, it was suggested that the difference be an important point that generated a new function.

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Engineering design is the process for generating a concept of useful artifact or product based on various kinds of scientific and engineering knowledge. In the early stages of design process, a designer dynamically, flexibly and reflectively builds a concept hierarchy in order to clarify problems and solutions of design. This paper proposes a system that supports reflective process of building a concept hierarchy. The DRIFT system is used to capture the reflective process. KJ method is integrated into this system in order to support smooth externalization of knowledge. A designer can evaluate externalized knowledge by QFD-based cost-worth analysis method. An example of a cellular phone design shows that these features promote a designer's reflection in building a concept hierarchy.

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An engineering analysis model is indispensable to predict the behavior of a product for its rational evaluation and optimization. In the process of modeling engineering analysis, an engineer makes numerous modeling idealizations or assumptions, which depend on a various factors of design, such as the objectives of the engineering analysis or design time constraints. Knowledge about such modeling idealizations is dynamic in nature. Because a today's product is getting more large-scaled and multi-disciplinary, management of dynamic knowledge about modeling engineering analysis becomes more important. This research aims to develop the system that supports and captures the process of modeling engineering analysis of a multidisciplinary system. This paper discusses issues of supporting a multidisciplinary design, and overviews development of a supporting system.

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It is method of much value to consider product architecture including product family for many companies which produce products. A good product architecture provides variable products which make many willfulness customer's requirement satisfied. In order to produce a good product family, a designer should consider product architecture, which defines relationships between customer's requirement, product performance and components. This paper develops a design method and design system of product family architecture considering variety of lineups, profit of platform modules and set-based design. In this paper, we propose a design method of product family by an extended Product Family Graph model. And by using fuzzy model, we can support variable commonalization of components with flexibility for customer requirement on a computer system. And by verifying easy test cases, we try to increase common component and reduce product costs.

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Recent years, the template design method has been gathering attention to reutilize the design knowledge efficiently. It can be said that design Template is a sequence of information to decide product specification, but it is not strictly defined because it requires general versatility and independence. In the research, design template is defined as a sequence of information of supposed customer requirements, designers' intention, and assumption of design with top-down product knowledge model. And the method on effective utilization of template is proposed to derive design process according to various customer requirements.

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Owing to the volume of data generated in recent computations and experiments, it is quite difficult to extract useful information from these data even if using scientific/information visualization techniques. Method or methodology to extract useful information from such data should be considered. Several concepts of very large scale visualization are proposed in this situation. Most of them are based on high-performance computing techniques or highly-efficient devices for computer graphics. In this paper, a flexible visualization methodology based on "analysis of visualization process" is introduced. A possibility that a visualization agent designed from a process model helps to reduce the difficulty of handling huge data is described.

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In order to develop the new alloy with which it is satisfied of the customer demanded alloy characteristic, it is necessary to determine processing conditions (casting, forging, the cooling method, etc.) with the type and quantity of an additive element. In an alloy design, the knowledge concerning the influence an additive element and processing conditions have on the alloy characteristic is indispensable. However, at an actual development, it is hard to say that those experience and experimental data are fully utilizable. This research tries the proposal of the system which supports the knowledge acquisition concerning an alloy development paying attention to data mining of experimental data.

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In this paper, the multi-objective design optimization of a high-lift airfoil consisted with a slat, a main wing and a flap is considered for a take-off condition. The design parameters are the elements' setting. Leading edge device, slat, should be deployed with the continuous motion from the take-off setting to the landing setting. Therefore, design space is defined with satisfying its requirement. Slat is considered zero-gap. Objective function considered here are to maximize the lift to drag (I/d) minimize the drag co-efficient (C_d) at nose up angle, respectively. Then, maximum lift condition is also considered, therefore other objective functions are to maximize maximum lift-coefficient (C_<lmax>) and maximize the angle of attack that becomes C_<lmax>. 16 samples are selected by Latin hypercube sampling method and they are evaluated using Reynolds Averaged Navier-Stokes Simulation (RANS). After this evaluation, Kriging models are constructed for each objective functions and the decision making (DM) is carried out with applying self-orgnizing map (SOM).

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Large wind turbine blade is prospected to be CF/GF hybrid blade made with Carbon Fiber Reinforced Plastic and Glass Fiber Reinforced Plastic, and structural optimization of the blade is multi-objective optimization problem (MOOP) about weight and material cost of blades. The optimum solutions for MOOP are Pareto optimum solutions. In this paper, the MOOP is solved using Multi-Objective Genetic Algorithm (MOGA). Meanwhile, blade structure is necessary to satisfy some constraints not to fracture under various load conditions. To evaluate the constraints, FEM analysis is used. This causes enormous calculation cost. In the present paper, to reduce this, some response surfaces approximating the degree of constraint satisfaction are created. Pareto solutions obtained using response surfaces don't necessarily satisfy the constraints because of approximation error. It is necessary to confirm whether they actually satisfy the constraints or not using FEM analysis. If some of the solutions have large approximation errors or don't satisfy the constraints, whose response data are added in, and the response surfaces are restructured to improve their accuracy. Repeating restructuring, obtained Pareto solutions will converge to exact Pareto Optima. As a result, the number of FEM analysis is reduced to 237 times.

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This paper studies the characteristics of optimal staking sequence for nonlinear vibration of laminated composite circular cylindrical shells. For this purpose, the backbone curve equation for primary resonance is derived analytically by using the Galerkin's method and the harmonic balance method. In optimization, fiber angles of each lamina for a symmetrically balanced laminates are taken as discrete design variables, and nonlinear and linear frequency are taken as object functions to be maximized simultaneously. In numerical calculations Multi Objective Genetic Algorithm (MOGA) with Fonseca-type rank evaluation, sharing technique and elitist strategy is employed, and thus pareto optimum solutions are obtained numerically. Finally optimal stacking sequence is discussed by comparing the backbone curves obtained for the pareto solutions.

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A new approach for multi-objective design optimization which combines CFD analysis and optimization techniques has been proposed and applied to the airfoil design for a steam turbine stator blade. In the present approach, genetic algorithm is used to search compromised solutions in the multi-objective problem. In addition, response surface approximation using the Kriging model is used together in order to reduce the computational time for objective function evaluation. As a result, the computational time required for the entire optimization process was kept within a realistic range. Moreover, the trade-off relations between multiple objective functions have been discovered, even though the accuracy of the response surface approximation was not yet in a satisfactory level. Finally, many design candidates that outperform the original baseline design have also been discovered.

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This monograph describes a data mining workflow to reveal design tradeoffs applying to three-objective optimization for regional-jet wing design with engine nacelle. Multi-objective optimization here was performed by using Self-Organizing Map (SOM), ANOVA, and Coincidence Testing coupled, the most importantly, with "Visualizations." More than one statistical method that examined high dimensional data (design parameters and the corresponding objective function values) allowed to reach a solid conclusion where global tradeoffs were visualized.

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Even though various visualization methods have been shown previously, 2D or 3D Scatter Plot is still consistently popular to see multi-objective spaces. However, these scatter plots cannot describe more than three objectives at once. This monograph proposes visualization methods to understand easier multi-objectives spaces using Profile Chart, which is usually known as Parallel Coordinate Plot. Additionally, it also shows Bubble Chart to describe feature of design spaces based on binned variables.

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The present design education using the two-dimensional CAD software and the engineering education based on classroom lecture in our university cannot respond to the rapid environmental change of the manufacturing industry appropriately. In addition, willingness to study engineering and enthusiasm for manufacturing of university students are vanishing. In order to provide undergraduate students with opportunities to experience the whole process of product manufacturing including three-dimensional computer aided design, computer aided engineering using finite element method and fabrication, Faculty of Environmental Engineering of The University of Kitakyushu attempted the engineering design and manufacturing education by use of 3D CAD and CAE. In this paper, we report the experiences and the results of the educational activities.

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This paper describes development of design education support system. The system shortens duration of initial design with reference to database. It takes time for students to explore data in many books, select required data, find estimate curve by plotting selected data and calculate. The system supports these processes and shortens duration. A case study is performed applying the system to ship initial design. An experiment shows that students can determine principal particulars in short time on the design education support system.

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All works on design and manufacturing processes are not completed by one engineer. These processes most commonly are managed by a project-based team. Therefore, Design and manufacturing educations need to cooperate with Systems Engineering (SE), Project Management (PM) and Mechanical Design (MD) educations in the years to come. In this paper, we develop an education program for bachelor students in the department of Machinery & Control Systems. This program makes to cooperate with MD of a professional subject and SE of a common subject in the faculty of Systems Engineering. This has been executed through Project-Based Learning (PBL) since 2004. We report this program and discuss.

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Recently, as the technologies surrounding Mechanical Engineering has improved remarkably, the expectation for students graduated from department of mechanical engineering too has changed a lot. For example, in order to develop a mechatronics system, a student needs to integrate wide varieties of technology, such as mechanical engineering, electrical and electronics engineering, and information technology. Therefore, from the perspective of education, past education system which stresses on expertising each technology should be replaced by an education system that stress on integrating multidisciplinary knowledge. In this paper, a trial collaboration education program between university and high school is described, where by students are required to integrate multidisciplinary knowledge in order to develop a biologically-based robot.

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This paper points out the difference in design education with special attention paid to PBL between Japan and US. While Japanese PBL emphasizes tactical importance, US one emphasizes strategic importance. And Japanese PBL seems to emphasize the importance of individual capability improvement, US one does more on the importance of a group capability importance. This may explain the fact why US emphasizes the importance of diversity and Japan does not so much.

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In this research, we analyzed the automotive market bringing the automotive performance from about 300000 models from which they were open to the public from 1982 to 2006 years about 20000 models by Data Envelopment Analysis. DEA is the method that can make clear about superiority or inferiority of business unit with multi-dimensional index and showing improvement of business unit. As a result, we can show trends from graph where horizontal axis was assigned as each performance index and vertical axis was assigned as each efficiency value obtained by DEA. We showed design index of automotive in the future by sensitivity analysis. From the above-mentioned method, we can confirm DEA is the effective method as method of evaluating products with multidimensional index.

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Machines have been produced with fixed functions, but as diversification increases and situations change more often and extensively, necessary functions change with time very frequently and extensively. Traditional machines operated by commands. But command based operation will no longer be effective, because necessary operations change with situations. Therefore, machines or systems that sense the necessary functions are needed today and what is needed for realizing this kind of systems is learning capability. It is expected that such learning capability will also create new markets.

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This paper discusses the importance of story-based design for creating new markets. Industry has traditionally developed products for geographically defined markets. But with increasing diversification and with quickly globalizing society., the theory of market economy does not work any longer and we have to develop approaches for creating new markets. This paper points out that although our product value has been context independent, we should change our way of thinking and regard product value in context. In other words, we should develop stories which would enhance product values.

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We present a novel geometric algorithm to construct piecewise smooth surface models based on subdivision that interpolates a triangular mesh of arbitrary topological type. All sharp features such as creases and corners of the original mesh model are first identified, and then we assume that the given triangular mesh is a control net of the subdivision surfaces. Next, the control points are iteratively updated preserving all the sharp features by a simple point-surface distance computation and an offsetting procedure without solving a linear system. Some examples are provided to demonstrate the proposed approach.

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We present a method to reconstruct a voxel-based 3D model from several 2D images of an object of different views. The data acquisition system consists of a camera on a tripod, and a computer controlled turntable. We employ a so called Shape-From-Silhouette (SFS) method which constructs a voxel-based 3D model from silhouette images. The obtained voxel model is further carved by the voxel coloring technique. As a final step, we deform the surface voxels to reduce the staircase effect. The reconstructed models of complex objects show the effectiveness of our inexpensive data acquisition system.

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Recently, 3D scanners are significantly improved and a state-of-art 3D scanner can measure tens of millions of points in only one scanning. However, most PCs cannot handle such a large number of points because of the limitation of memory space. We intend to build 3D models of a manufacturing facility. Although it is difficult to process the huge data of an entire facility in limited memory space, most components in the facility can be processed if they are separately stored. Therefore, we subdivide a huge point-cloud into sub-sets, generate mesh models from each set of points, and merge mesh models. We applied our technique to point-clouds of a nuclear power plant.

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In this paper, we describe a new method of free space extraction from a 3-D assembly model using voxel data. Our approach is an extraction of 2-D free space on cross section images and a construction of voxel data from these images. An experimental result shows that our method is enough fast and accurate.

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