The main target of product design is to clarify the relationship among the processes such as required function, behavior, geometry, etc. During the product design, the kinematic analysis assures the product′s behavior. The errors of product′s geometry cause the unrequired behavior. The unrequired behavior is useful information for product′s high quality. This research calculates the behavior area due to errors. The sensitivity analysis is also used to clarify the relationship between the errors and it′s behavior area.

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The design considering product performance within tolerance will be required to produce better product. Statistical tolerance indices are useful tools for the performance design. To decide statistical tolerance indices, it is needed to know the relationship between statistical tolerance indices and product performance. In this study, it is assumed that performance model is normal distribution within tolerance and product is composed of simple parts. Then estimated value and standard deviation of performance are calculated and associated with statistical tolerance indices Cp, Cpk, Cc and Cpm.

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[in Japanese]

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Compliant mechanisms generated by traditional topology optimization methods have linear output response, and it is difficult for traditional methods to implement mechanisms having non-linear output response. To design a monolithic and practical complaint mechanism having a specified nonlinear output path, a two-stage design method based on topology and shape optimization is constructed here. In the first stage, topology optimization generates an initial compliant mechanism based on ordinary design conditions, with ″additional″ constraints that are used to control the output path at the second stage. In the second stage, an initial model for the shape optimization is created, based on the result of the topology optimization, and the additional constraints are replaced by monolithic structures that perform the same function as spring or stopper elements. The shape optimization is then executed by using parameters that represent the outer shape of the compliant mechanism and additional structures, to generate a detailed shape of the compliant mechanism having the desired output path.

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Generic resource model is proposed in order to plan a schedule for production resources including machine tools, assembly robots, AGV, storehouses, material shelves, buffers, and so on. This paper focuses especially on the role of the buffer, and the differences among these resources are analyzed. A unified scheduling formulation is derived from the analytical results based on the model. A job-shop scheduling problem is formulated as Mixed-Integer programming and an optimal schedule for the production system with proxy resources is discussed.

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[in Japanese]

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In this study, auction type scheduling method is proposed for machining job shop in order to automate scheduling and make daily management easier. Real-time scheduling using auction-based algorithms are performed to make decision of each job order. Simulation by using same algorithms is simultaneously executed to forecast tardiness of jobs and take measures such as extension of working time. Additional auction-based algorithm is also proposed so as to improve autonomous creation of larger lot size. Effectiveness of this algorithm is investigated by simulation studies.

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[in Japanese]

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Process planning plays a key role in modern manufacturing. And it provides the functions which translate designers′ intentions and finished parts′ specifications into technologically feasible plans describing how to manufacture a functional part efficiently and precisely.
The task of automatically generating a process plan from a solid model representation of a part is normally subdivided into several activities such as: selection of the machining operations, selection of tools, selection of fixture systems, sequence of the machining operations, evaluation of the machining time and cost and so on.
This paper proposes a machining process planning system which can flexibly perform process planning, considering design intentions and dealing with disturbances in the manufacturing process by choosing the optimum plans from multiple candidates.
As a result, the system proposed in this paper can be expected to provide more available candidates to reduce manufacturing time.

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[in Japanese]

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Retaining machining information is an important element for generating high quality NC data. However, existing NC data (ISO 6983) cannot be used for generating high quality machining information because they do not contain machining features, cutting tool information, workpiece information, and so on. In order to solve this problem, a method of retaining machining information (workingstep) is proposed in this research. The workingsteps are obtained by analyzing and transforming existing NC data to CNC data model (ISO 14649) which represents explicitly technical information, such as machining features, cutting tool information, workpiece information, and so on. In this report, in order to determine correspondence of roughing workingsteps with finishing workingsteps, model of NC data and tool information including pairs of roughing and finishing workingsteps is proposed.

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Supply chain should be continuously designed and redesigned in order to dynamically configure suitable clients and suppliers in multiple supply chains. The previous research proposed a dynamic configuration method of supply chains. The proposed method provides suitable delivery time and prices of products by the negotiation between clients and suppliers and by the modification of the existing production schedules of suppliers. The actual delivery time of some products is later than the contracted delivery time in the modification process of the production schedule. The clients permit the delays of actual delivery time by accepting the penalty cost for the delays. However, the supplier loses the credibility with the clients in the actual supply chain. This research evaluates the credibility of suppliers from the viewpoint of the delay of actual delivery time. Some computational experiments are carried out by using a prototype of supply chain simulation system in order to evaluate the effectiveness of the proposed method from the viewpoint of the credibility of suppliers.

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This research deals with a dynamic supply chain model, which represents the decision-making process of a set of clients and suppliers. The suitable prices and delivery time are determined through the iteration of the negotiation process among the clients and the suppliers and the modification process of the production schedule. It is impossible for the suppliers to simultaneously generate suitable prices and delivery time of two or more new products in the decision-making process. This research improves the dynamic supply chain model in order to generate suitable offers for multiple orders from two or more clients.

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This paper presents a theoretical framework for supply network integration in a multi-product manufacturing economy making use of the walrasian market system. We propose a method of dissolving a supply network into a competitive market and then applying the theory of Computable General Equilibrium (CGE) to find an optimal allocation of resources. Agents in the supply network are represented using the Cobb-Douglas (CD) function with a constant return-to-scale. A simulation program based on Market-Oriented Programming (MOP) was developed to mimic the trading environment in order to search for a pareto-allocation of resources in the network. The experimental results presented reveal that this framework can be adapted for use in drafting a holistic picture of a supply network in a multi-product manufacturing environment.

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An appropriate setting of re-planning period is quite important factor for efficient manufacturing. In this study, a distributed manufacturing system simulation environment, named Distributed Virtual Factory (DVF), is developed and a PUSH type production management system is executed on it. We evaluate the influence of re-planning period on production cost by simulation experiments, and discuss the appropriate policy on re-planning period in case studies.

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The curve is the most basic design element to determine shapes and silhouettes of industrial products and works for shape designers and it is inevitable for them to make it aesthetic and attractive to improve the total quality of the shape design. If we can find equations of the aesthetic curves, it is expected that the quality of the curve design improves drastically because we can use them as standards to generate, evaluate, and deform the curves. The author has proposed the general equations of aesthetic curves as such a standard. In this paper, we show that the necessary and sufficient condition for a given plane or space curve to have the self-affinity and the self-affinity condition can derive the general equations of the aesthetic curves.

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A curve shape modification algorithm based on the specified curvature for CAAD is described. A Bezier curve with inflection points is modified by the specified curvature distribution. Redefinition of the control points and degree determination for the modification algorithm has been discussed. Then, examples of Bezier curve shape modification are given.

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[in Japanese]

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We propose a method which controls continuity of triangular spline surfaces. Many present industrial products have compound surfaces. So triangular meshes have been used to express a product. Subdivision surfaces are used to interpolate triangular meshes. Subdivision surfaces generate surfaces that are automatically filled continuity for arbitrary meshes. However, subdivision surfaces cannot generate creases to an arbitrary part of them.

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[in Japanese]

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Connecting some meshes is required for realizing mesh-based efficient CAE, for example, generating assembly models or setting analysis conditions. This paper proposes a new mesh combining method for triangular and tetrahedral meshes. First, the connectors which connect given two meshes are inserted, and then they are removed by the edge collapse simplification. As a result, a connected mesh that has coincident elements on the shared portions can be obtained. Our method is applicable to the meshes that have no-coincident elements and geometries on the portion to be connected, and it supports several types of mesh connections, i.e. curve-curve, curve-surface, and surface-surface connections.

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This paper proposes a development of generation system which makes an extensive area and application of surface texture .Multiple narrow domain surface textures that measured with microscope-type surface profiling instruments change a large field of surface textures using stitching, Using measured data, it resolves the issue in which texture cant depict refined shapes finely. PC-cluster constructs a parallel processing system. The system operate in parallel with MPI. As a result, textures created with the system are more refined than conventional textures. Moreover, the execution of the generation with the parallel processing is more efficient than doing with a serial processing.

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[in Japanese]

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In this paper, we propose a new deformation method for mesh models to directly specify dimensions of the mesh model using parametric deformation method based on barycentric coordinates for convex polytope. First, a mesh model is segmented using feature edges and surface parameters for each segments are calculated. Second, we select one or two segment to define dimension such as distance between two planes and radius of cylinder, and also select some segments to define non-deformed regions. Then deformation handle of parametric deformation method is automatically constructed based on the selected segments. Finally, mesh model is deformed by changing deformation parameters calculated by target dimensions.

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In an aesthetic shape design, considering curvature variation is important. We have developed the method to generate a surface using a curve-ruler moving along two guide curves. In this study, based on our method, generalization of the ruler-suface generation process is conducted because the former formulation is not suitable to introduce parametric form functions as a curve-ruler. By this improvement, the function of a curve-ruler is chosen as one of the aesthetic curves, for example, a logarithmic spiral or a clothoid. Designer only designates the function of the curve-ruler and changes its parameter to create the surface. The new surface generation process is explained and examples show that the presented improvement is effective. In these examples, surface shape is easily modified by changing the curve-ruler function and ruler parameter.

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In upstream design, we generate blueprint as a preparatory step in deciding the concept of shape. This process is important in forming the overall design object. However, there is no sufficient framework to support design based on both language and shapes. As process of our study, the first task is to propose linguistic model and choose shape model, for matching. In this task, we proposed Linguistic Relations Model (LRM) as linguistic structural model. Then we elected Constructive Solid Geometry (CSG) as shape structural presentation. The second task is to propose method to match between linguistic knowledge and shape data by statistical approach. The third task is to evaluate our method to match between language and shape by statistical approach. In conclusion, results described above indicated that our method enabled the matching of each primitive component, and matching of each structural tree

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[in Japanese]

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Recently, mesh deformation techniques have been intensively studied. Such methods are useful for supporting style design, in which geometric shapes are often modified and evaluated. However, very few papers discuss the quality of deformed surfaces so far, although surface quality is essentially important in industrial design. In our research, we investigate how mesh quality, including mesh sizes and aspect ratios, is related to surface quality and then we discuss problems to be solved.

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Shape deformation by using Finite Element Method outputs accurate results, but this method needs much calculation, and requires various ideas, for real-time processing.
Our method using tensegric model and t-FFD is effective to simulate a shape deformation of complicated models with an interactive speed.
This paper proposes a method to constrain the deformation of the tensegric model, as if it is tightened by a wire-like object. When tensegric model is deformed, the wire-like constraint tries to keep its length, and affects the model with pseudo forces.
This method is expected to simulate the shape deformation of a human body constrained by a wearing corset.

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This report presents a technique to generate a hair form model in facial modeling from three pictures ( a front view and both side views ) on an individual′s face including his/her hair. In our method, we use a generic model, which is composed of a facial model and several hair models separately, and by transforming the generic model to the individual′s facial model and hair model with use of the information of feature points obtained from the pictures and by mapping the texture also obtained from the pictures, we can obtain a realistic individual′s facial model including various types of hair styles. As a basic technique when we transform the generic model, we use the GFFD (Generalized Free-Form Deformation) method that we had developed originally.

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Recently, as CAD systems have been spread, style design with digital mockups has been used. But the method using physical mockups is still used to evaluate products from ergonomic design. However, the conventional methods of the evaluation using a physical mockup of a product are inefficient in an upstream style design process, for it costs time and money. So, our research purpose is to develop a system for ergonomics design, which enables an ergonomics evaluation for a palmtop IT device without ″real″ subjects and physical mockups by integrating a digital hand with a product model and its task operation model.

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[in Japanese]

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[in Japanese]

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This paper describes a method for constructing CAD data from 3D sensed data for the purpose of realizing reverse engineering. In CAD data of many industrial products, manufacturing features such as flat planes and cylinders are defined on the boundary surfaces. In the proposed method flat planes, cylinders and cones can be extracted robustly from the complicated geometry or high noisy sensed and CAD data that contains the features can be constructed. The robust feature extraction is done through the following approaches:(1) Estimating geometric parameters of the features using the Gaussian image: and (2) Extracting the features by using ″growing surface method″. The method has been applied to some 3D sensed data and the validity of the method was confirmed.

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This study is conducted to promote the efficiency of the product designing process. An efficient method to re-construct surfaces in the phase of surface evaluation is proposed. Usually, evaluation of the quality of product shape is implemented by checking up the pattern of highlight lines, reflection of fluorescent tubes arranged parallel to each other. However, if required highlight lines are not obtained, the models should be modified by numerous procedures. In this study, a system for constructing surface which shows the required highlight lines entered intuitively with mouse or pen tablet device is constructed. As results, (1)a method of defining an evolute which stands for the locus of the curvature centers in the cross section of the surface from highlight line information was proposed, (2)that surface showing the required highlight lines defined by the involute can be obtained is clarified, (3)the system was constructed by mounting the algorithm on the computer based on the proposed method and (4)The usefulness of the proposed method was confirmed through fundamental experiments.

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Today, there have been demands for a manufacturer to develop a new product in short period of time, because life of products is short. Therefore it is necessary to shorten the development period of the model more in production system. In this research, we develop a new production system which supports the designer by using the reconstruction of solid shape and the tool pass creation technology when processing with machining centre from the photograph image. This system can decrease the labor to which the designer changes CAD file when he repeats the optimization process. In this research, we compared the actual object with output data which had been obtained from the photograph image.

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[in Japanese]

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Reliability design is necessary for Life Cycle Design in early design stage. In this paper, we propose the method to describe functional stream among parts which is intended by designer. Referring it to behavior analysis result, we would check unintended behavior or malfunction. We define part′s relation based on part′s behavior and set part′s internal state to describe part′s relationship which changes contact through realizing function.

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To achieve a reliability design for a product, it is necessary to break down the product structure in components and analyze their influence on the entire product function. The aim of this research, is to 1) propose a method to evaluate reliability, 2) make a computer aided reliability design system. The objective of this paper is to examine a method to analyze product behavior and a method to express failure modes for the reliability design system.

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[in Japanese]

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Environmental consciousness has gained more and more interest in recent years, and product life cycle design that aims to maximize total performance while minimizing its environmental load and costs should be implemented. To achieve that, the rise and fall in product value along life cycles should be evaluated properly. This paper proposes a practical evaluation method for the product value along life cycle by correlating it with product functionalities, and design guideline for maximizing product performance through product life cycle with balancing its value, environmental load, and costs. Calculation process of total performance is illustrated with an example of laptop computer, and the feasibility and effectiveness of our design guideline is also demonstrated with an example of laptop computer.

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For the purpose of supporting the effective reuse of products, we are proposing the Part agent system that manages the information on individual parts and products using the technology of network agent. Part agents will be attached to the corresponding physical part via network. A Part agent will manage all the information on the part such as its level of deterioration and all the related information such as the market information. They will provide user of the part with appropriate advices on maintenance, which will make effective reuse of the part. We are developing the simulation system of Part agents for the investigation of their feasibility. In this report, the basic simulation mechanism is described that is developed for the prototype simulation system including 3 sites representing the life cycle stages of products and 20 products.

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Recently, various laws and regulations which require the information discloser on chemical substances that are contained in a product and in its production activity have been installed globally. Under this circumstance, production information management system to assess the adaptability to those laws and regulations are required. The purposes of this research are to develop an information system for batch production which can be used for the assessment of chemical substances contained in a product. We will firstly design a general-purpose law model so that revisions of the system will not be necessary for changes of laws and regulations. Next, we will develop a function that is able to add up chemical substances contained in a product or input and output energy in the manufacturing process.

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Toward sustainable society the global resource circulation, which multilaterally trades secondhand products and scrap metal attracts attentions. In fact a wide variety of models of the global resource circulation has been developed and material flow among multiple regions are often analyzed. However, the uncertainty in the global resource circulation is not evaluated quantitatively in those models. This paper proposes a global resource circulation model involving the uncertainty by using risks and discusses the possibility of stable resource circulation in Asia. Finally, in order to verify the validity of this study, an example of circulation of desktop PC is analyzed. The results of the example indicate that product reuse is effective in successful circulation and risk management is indispensable.

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[in Japanese]

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[in Japanese]

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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 receiver's value. This paper aims at proposing a method for forecasting receiver's demand change based on a concept of customer's value importance.

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This paper reviews nowadays situation on selling electronic products based on a literature research. The analysis of market surveys identifies the potential improvement to develop customized electronic products. The driving factors for the mass customization of electronic products are an increased customer satisfaction as well as economical and ecological aspects. An approach is introduced to optimize the development process of electronic products by integrating the customer.

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We have applied the Service Engineering method to the IT solution field through backward analysis, or reverse engineering. As a case study, we have analyzed a large-scale information system, which was developed and deployed in a short period of time, and has been well managed. The success factors are validated and confirmed using the Service Engineering concept and expression. In this paper, the results of the analysis are reported according to the system realization stages: concept making, system construction, and after service-in. Through this process, we are able to demonstrate and recognize that the Service Engineering concept is valuable in leading projects to success in the IT solution field.

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[in Japanese]

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