This paper proposes a new 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 from the 3D sensed and CAD data that contains the features can be constructed. In the feature extraction, the feature that satisfies geometric constraint can be also extracted. The method has been applied to some 3D sensed data and the validity of the method was confirmed.

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Reverse engineering is applied to design tailor-made undergarments, such as brassieres, girdles, and so on. A 3D scanning device has been used to measure the human body shape of a customer. However, it is not sufficient to know the size or shape of a body for well-fitted undergarments, because the customer wants to know how the body is constricted and reformed by those products. We propose a real-time simulation system of body deformation according to the type and tightness of undergarments. It is intended that our system is used by apparel shop clerks to show the simulation result to customers and to take orders.

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We present a simple and robust method for generating degenerate hexahedral meshes by using VCAD system for structural analysis. Our method consists of only two steps: First, dual meshes are computed from VCAD models. Second, the positions of new vertices are computed by least-square fitting. Concave elements can be eliminated completely by simple subdivision of hexahedrons. We also demonstrate the results of structural analysis by our meshes and discuss strengths and the limitation of our method.

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The study of smooth surface reconstruction from a set of 3D range data obtained by a laser scanner has become increasingly important in the area of reverse engineering, animation, and scientific visualization. The most popular representation for fitting such data in geometric modeling is the tensor product B-Spline surfaces. However, it is extremely difficult for tensor product surface to handle surfaces with arbitrary topology, and to maintain continuity conditions near the extraordinary points. New class of surfaces, called subdivision surfaces, which offers an alternative to the tensor product B-Spline has recently received attention in computer graphics and geometric modeling. We present a novel geometric algorithm to construct a smooth subdivision surface that interpolates the n vertices of triangular mesh of arbitrary topological type without solving a linear system. We start our algorithm by assuming that the given triangular mesh is a control net of the Loop subdivision surfaces. The control points are iteratively updated by a simple point-surface distance computation and an offsetting procedure. The complexity of our algorithm is O(mn) where m is number of iterations. Therefore it is very fast compared to the conventional fitting methods, as m>>n.

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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. 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 authors have proposed the general equations of aesthetic curves as such a standard. We show the essential improtance of the self-affinity and extend the aesthetic plane curve into 3-dimensional space.

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A solid model representing product requires fillet or blend process, which rounds a specified edge or vertex, in order to make a production model for manufacturing purpose such as mould die model. Current major CAD systems are based on boundary-representation (B-rep) solid model and their faces are consists of trimmed free-form surfaces. In many cases, blend (fillet) process becomes unstable at edges of narrow faces or at both ends of such faces. We propose that a new boundary-representation structures and new blend algorithms which enable to make robust blend process. In this report, we propose a new vertex-blend method.

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It becomes apparent that problems in shape data quality cause tremendous economic loss in mechanical industries. In order to resolve these problems, automotive manufacturers jointly create a guideline to improve the quality of product shape data. This paper describes the development of ISO 10303-59, the international standard for product shape data. The standard has been proposed to ISO and is being developed by Japan to capture the quality of product shape data correctly and to promote the circulation of the quality information. The scope, anticipated usage scenarios, management of shape data quality and its representation is described as well as the current development status of the standard.

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Previously, we have optimized a cooling pipe layout so that an injected plastic product is cooled down uniformly and rapidly in order to reduce residual stress that is one of the factors of defects in the molded products. But there are many other factors affecting generation of residual stress such as die temperature, coolant velocity and coolant temperature. In this paper, the cooling conditions and the cooling pipe layout are optimized simultaneously for the reduction of residual stress in plastic products. In the optimization processes, the basis vector method controls a cooling pipe layout and the design of experiment (DOE) decides a combination of levels of cooling conditions and basis vectors. Then numerical simulation based on DOE is adopted to calculate a temperature distribution in the die. An optimum layout and cooling conditions to optimize a response surface constructed by the numerical results are obtained.

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The conceptual design phase contains uncertain design variables, and therefore the analysis using finite element method (FEM) is difficult to apply to this phase. We propose a set-based FEM based on the preference set-based design method, which is possible to analyze structures in the conceptual design phase. This paper presents the applicability of the proposed method by applying to structural analysis of a truss.

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In this paper, we present a numerical method to optimize the cross section shape of solid structures, which is often needed at the preliminary stage in the structural designs of automotives and airplanes and so on. The cross section area is minimized subject to sectional properties such as moments of inertia of area, center of gravity, boundary length. The problem is formulated as a distributed optimization problem, or a non-parametric optimization problem. The shape gradient function is derived using the Lagrange multipliers and the material derivative method. The traction method, or a gradient method in Hilbert space is employed to determine the smooth optimal shape using the derived shape gradient function. The validity of this method is verified to obtain the optimal shape of cross section under the constraints of sectional properties through an example.

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A new optimization method which can search for the multi-objective optimum solution is described. The feature of the new method include utilizing the constraint transformation method, creating orthogonal arrays, and changing the level values of design factors for every search step. As a result of applying the method to a multi-objective optimization problem, it is shown that the method can search the set of Pareto optimal solutions effectively.

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We obtained a high-rigidity and light-weight structure for an X-ray CT scanner gantry using topology and shape optimization methods. The optimization procedures were as follows. First we calculated the deformation caused by an imbalance of centrifugal forces and evaluated the strain energy density of the X-ray CT scanner gantry ; we focused on the stand through the calculation of the strain energy density. Then we determined the required stand stiffness satisfying the acceptable deformation that is the design specification to obtain high-quality tomograms. Finally, we optimized the stand under the constraint conditions for the stiffness. Thus, we confirmed that the optimized procedures have effectiveness for the X-ray CT scanner gantry design.

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When we apply the optimization algorithms to target problems, it is necessary to select the appropriate algorithms according to the characteristic of the problems. Moreover, the control parameters of the algorithms significantly affect the search ability. Therefore, it is also necessary to determine the appropriate parameters. However, the strategy for solving these difficulties depends on the knowledge and experience of users. Therefore, it is not easy for ordinary designers. In this research, we propose the strategy for dynamically controlling plural optimization methods. There are two features of the proposed strategy ; 1) the maximum time to execute the optimization algorithms is defined, and the purpose of the strategy is to obtain the better solutions for the limited time, and 2) the landscape of the search space can be roughly grasped after the optimization. We show that the proposed strategy is a effective tool for the design problems.

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Most of the existing conventional optimization approach implicitly assumes that the system design process is deterministic and for a given input the optimized system will always produce the same output. However, in real world application, this is not true. In fact, in the real world, many engineering design optimization problems have parameters with uncontrollable variations due to noise or uncertainty. These variations can significantly degrade the performance of optimum solutions and can even change the feasibility of obtained solutions. Therefore, robust optimum solution is an important area of research in engineering design optimization. Many researchers in the past have investigated the impacts of uncertainties in design optimization techniques including evolutionary algorithms. However, hierarchical class of design optimization problems under uncertainty is not yet investigated using evolutionary techniques. In this direction, this paper attempted to explore the uncertainties in design parameters and its impacts on optimal solution using HGA. In order to achieve robust solution, the HGA has been applied to solve a hierarchical series redundancy optimization problem. The impacts of uncertainties on optimum solutions have been studied. In sum, the research work in this paper is an effort to develop a robust evolutionary algorithm for design optimization under uncertainties.

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We deal with an optimal pathway layout based on the recursive optimization approach with the ground pathway method. Self-similar configuration of ground pathway is introduced. Recursive optimization problem is formulated based on an electric resistance model of pathway elements. An example pathway layout design is conducted to demonstrate the feasibility of the proposed optimization approach.

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We discuss the network representation method for calculating railway fares. The railway system has a typical network structure consisting of stations as nodes and railbeds as arcs. When we, however, try to represent junctions on the network, we encounter some problems. For example, there are several complex junctions that cannot be represented by integrating nodes associated with the junction or introducing dummy arcs with a distance of zero for a connection node on foot. We show an idea for network representation in order to apply algorithms to the shortest path problem, which is the basis for calculating railway fares. Our surrogate network finds the shortest path between two specified stations exactly.

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Data mining is the process to find some patterns or rules from the large volumes of data automatically. It is classified into six fields ; classification, estimation, prediction, association rule, clustering and profiling. We focus on data clustering and classify the similar data into same clusters. These clusters can be used in preparation of data analysis, finding segmentations in market and so on. We apply "Multiobjective clustering with automatic determination of the number of clusters: MOCK". MOCK uses two complementary objectives based on cluster compactness and connectedness, and returns a set of different trade-off partitioning over a range of different cluster numbers, k. It is able to find the appropriate number of clusters based on the information of the trade-off curve. In this paper, we considered the scalability of MOCK with along to the increase of the number of the data. Especially, we used web data clustering for examining the scalability.

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This paper reports a conception of hierarchical optimization method for layout design. After reviewing the mapping between decomposition methods under the trend of multidisciplinary design optimization and complexity of layout design problems, the promises and challenges in applying hierarchical decomposition to layout design, which is typical of combinatorial optimization problems, are described. The nature and modes of interactions between the whole layout of the whole system and the partial layouts of partial subsystems are characterized, and a coordination scheme is tentatively investigated based on them. Its applicability to layout design of high-density packaging products and issues to be challenged are discussed.

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We propose an algorithm to find the lowest-fare path between two specified stations in the JR-EAST area where the IC-card ticket will be available in 2007. The lowest-fare path is sometimes different from the shortest path, because JR-EAST has many exceptional calculation rules in addition to the four calculation-tables used for the three specified areas and two kinds of lines, i.e. the main line and local line. Our algorithm solves at most only four shortest path problems for the fare between two specified stations, although it can deal with the complex situation mentioned above. Therefore the algorithm can calculate fares between all pairs of stations not only very quickly but also exactly.

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This paper describes an easy VR system which has a wide arch screen and stereoscopic image projection. It is driven by several PCs connected by network shared memory system we developed. Network shared memory system is designed for easy use and to keep compatibility to old applications we developed on UNIX workstation. On this system, we develop a house designing application and data conversion method from architectural CAD to VR data.

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An approach to haptic interaction with deformable and moving object is proposed. In our approach, the behavior of an object is defined by a set of temporal deformation patterns after impulse force is applied to each degree of freedom, which we call impulse response deformation model. Deformation resulting from interaction is obtained by computing convolution of the model and the history of interaction force. Motion resulting from interaction is obtained by dynamics simulation. The time complexity of computing interaction force is independent of the complexity of the model. This feature is advantageous for time-critical applications. Also, the time complexity of computing object deformation is linearly proportional to the complexity of the model. Through implementation of a prototype environment, feasibility of the proposed approach is demonstrated.

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Exclusion is a pushing manipulation of organs for making hidden organ visible or enlarging workspace. Improper manipulation has possibility of danger. The authors propose a surgical simulator especially for organ exclusion with FEM-based soft tissue deformation and multi-finger force feedback device. Interactive stress visualization supports understanding of stress concentration by manipulations. Developed system allows interactive manipulation of organ by fingers with stress visualization. Simultaneous contact by four fingers was possible with the developed system. An experiment of training trial suggested effectiveness of stress visualization to lower stress concentration. Subjective evaluation by surgeons showed high potential of the simulator for training use.

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This paper discusses the construction of the sunstance projection display and the interaction with it. This display system is composed of an object in the free shape, a video projector, and the sensor to measure the object's position/posture and the user's eye. The user can perceive the projected virtual object in three dimension that locates inside the screen object, since the eye-motion parallax and object-motion parallax gives the 3D cues to the user.

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There are some researches that index a desktop manipulation videos and reuse it for automatic task instruction system. The purpose of this study is to use a small robot as an assistant and support a user in finding required objects from the real world. Based on the survey of the previous studies, we derived the effective actions to for an assistive robot to support projectability in communication. Finally, an experiment showed that such actions are effective in improving efficiency of an automatic instruction system.

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Distance education using video chat has become popular according to the expansion of broadband networks. However, conventional distance education using video images lacks the feeling of presence and have difficulty in the case of using the three dimensional information. This paper proposes high-presence distance learning system using immersive projection technology and video avatar.

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This paper proposes a visualization method that intelligently extracts relevant information from enormous source of data. Our method consists of three phases: (i) modeling of a relationship network that can show different visualization for different research field, (ii) analyzing each researcher's thinking process during information search phase, (iii) Creating interactive visualization interface that adapts to the feedback from many researchers. By realizing this method, we believe that we can obtain more meaning from enormous data source because we are able to view the data from several point of view.

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This paper describes the basic characteristics of a new haptic display called TextureDisplay44FX (TD44FX) that presents both tactile (cutaneous) sensation and force sensation (proprioception) at the user's fingertip. The design principle is discussed first based on the results of earlier work performed on the vibratory pin type haptic displays. The TD44FX consists of a cutaneous display that has forty-four vibratory pins and a force display composed of two PHANTOM Omni force feedback devices. The structure of pin support that implements a dense pin array and the amplitude of vibration are presented. Sensation scaling at 50 and 250Hz was performed to establish the basis to produce controlled sensation intensities.

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A dental training with a mannequin causes several problems due to the lack of reality. To improve reality for effective dental training, we propose a dental training system using the mixed reality technology. In this system, a virtual patient is created and students are able to train dental operations with seeing the image of the virtual patient and touching the real mannequin. This paper applies a presentation method of haptic rendering using a virtual object called proxy in this system, and we express a force to cut teeth in dental treatment. We improve the motion of proxy to reproduce specific transformation method of virtual teeth.

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In Orient medicine, pulse diagnosis is one of the most important diagnosis methods. Because pulse diagnosis is very sensitive, and it requires high level of skill and long experience, it is mostly difficult for a trainee to master. It is also a problem that pulse diagnosis is a technique depending on feelings of separate doctors without a clear standard. In this study, the volume change of the surface of the skin caused by pulsation of the artery was measured as a method of settlement of the above issue point, and the development of the device to analyze pulse diagnosis quantitatively was tried.

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This paper describes an acupuncture educational training system using virtual reality technology. Trainee practices acupuncture to a human acu-points model in the 3-D virtual environment. 3-D magnetometric sensor is used for positional detection of head and needle. The novel point of the system is not only visualizing invisible acu-points but also guiding trainee during training. Trainee gets his trial result of his acupuncture position and the correct depth information from the window in real time. As a result, trainee can learn where he should pierce the needle more easily than the current training. Thus, an acupuncture educational training system provides more clearly and effective learning for acupuncture.

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In recent years, many endoscopic surgeries are performed because they are minimally-invasive. Since endoscopic surgery needs advanced operative technique, development of the training system using robotics or virtual reality technology is desired. In endoscopic surgery, the operation technique of forceps is important and its training system is developed. But, the insertion of trocar is not considered. In this study, we develope a haptic device for the trocar insertion training system. Then we conducted the basic force feedback experiments.

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In order to obtain a good design and manufacturing result, it is necessary to equip the designer and manufacturer with a support system related to casting design or so called, knowledge transfer and creation system. In recent years, the design supporting system using VR technology is developed, and introduced in the manufacturing industry. The merit of using VR system is being able to carry out the stereoscopy of the product model drawn by 3D CAD, and to carry out the design review of the product model in the same size as thing. However, since many systems extend the display of the conventional 3D CAD, they cannot input annotation and so on directly in VR environment. In this paper, the system which can input and display the annotation in VR environment is developed. By drawing annotation to the product model displayed on VR environment, sharing of technical tacit knowledge and engineers' communication are promoted, and engineers becomes possible gaining physical tacit knowledge.

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Microsurgery training using a rat or other animals has been essential for both novices and skilful surgeons, which would be hard to execute under the current circumstances. Instead of using animals, a virtual microsurgery training system is proposed and precise three-dimentional motion tracking system has been developed in this paper. Motion tracking achieved by calculating an orientation of an operating tool from two images of tool's shadows generated by two parallel ray optical systems crossed at right angles.

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Performances of several kW class SOFC systems are regulated by cell performances and by performances of thermal managements ; the thermal management method is deeply related to the SOFC module design. 1kW class SOFC system has been operated with measurements of temperature, gas flow rate, gas composition analysis and electrical output of the system. Material and heat balance and energy flow is estimated by using the measured data ; the effectiveness of the compact design of the SOFC module is discussed.

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The shape of the diaphragm for switch modules is traditionally like a disk. However the diaphragms in the oval shape are required because of social needs such as miniaturization. In this study, in order to detect how the shape of the oval diaphragm effects on click characteristics, numerical analyses have been carried out. The width of diaphragm and the curvature of corner of the diaphragm are variables in design. As a result, it was recognized that the click characteristics of the oval diaphragm could be controlled by the variables individually.

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The highly reliable design methodology is strongly required at the conceptual design phase to achieve the highly reliable space transportation systems, especially the propulsion systems. Some catastrophic failures did affect severely the schedule delays and cost overrun at the later development phase, moreover caused some losses of mission and vehicle (LOM/LOV) at the operational phase. This design methodology for highly reliable liquid rocket engine has been preliminarily established and studied. It is applied to develop the conceptual design process of the health monitoring and management system (HM/MS) at the operational phase in this paper. The critical failure modes in the whole engine system are clarified to estimate the design reliability and to prevent failure occurrence. Some variables associated with them are extracted to monitor whether the critical functions will be lost or not during the engine or mission operation. The conceptual design process of health monitoring and management system for liquid rocket engine is proposed and discussed in this paper.

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Recent years, an electronic technique has been developing remarkably, electronics control has been applied to various control systems. Many sensors and actuators have been implemented into those systems, and an energy efficiency and a performances have been improved more than before. However the system has been more complicated on the other hand, and much time is needed in order to develop the controller of the system. In this paper, a method of automatic controller design for those systems is described. In order to automate design of an electronic controller, a evolutionaly computation is applied. First, the framework how to apply the genetic algorithm to the automation of controller design is described. In particular, the coding of a chromosome is shown in detail. Next, how to make an evaluation function is represented with an air-conditioner as an example case, and the controller of the air-conditioner is developed automatically using our proposal framework. Finally, the evolutionary simulation is performed to confirm our framework.

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We propose a novel method to remove irregularities of B-spline surfaces via smoothing circular highlight lines. A circular highlight line is defined as a set of points on a surface where the distance between a circular light and an extended surface normal at the circular highlight line is zero. It is very sensitive to the change of the directions of normal vectors of the surface, and hence can detect surface irregularities by observing its behavior. This method of correcting surface irregularities is very intuitive and allows non-skilled person to generate surfaces that can satisfy the requirements imposed by the downstream applications. Nonlinear equations that relate the difference between the circular highlight lines of the current surface and the target circular highlight lines in the parameter space of the surface are formulated in terms of control points of the surface to be modified. The nonlinear governing equations are solved by Newton's method.

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The purpose of this study is to introduce a new method to fit a set of point by B-spline curves/surfaces by geometric algorithms. Standard B-spline curve/surface fitting algorithms first associate suitable parameter values for each input point, known as parameterization of data, and form a linear system with control points as unknowns. In this paper we propose a geometric algorithm to construct smooth B-spline curves/surfaces that fit a finite set of points. Our method takes an approach that the initial shape is updated step by step by moving the control points to reach the target shape. It relies on a surprisingly simple geometric algorithm which iteratively updates the input control points mesh in a global manner based on a local point-surface distance computation and an offsetting procedure without solving a linear system. The complexity of our algorithm is O(mn) where n is the number of vertices to be interpolated and m is the number of iterations. Therefore it is very fast compared to the conventional fitting methods, as m<<n.

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We are developing the product design and the evaluation support system that evaluates the product from a multi viewpoint (procurement, manufacturing, and environment, etc.) by using BOM (Bill of Materials) of the product. This system has aimed to achieve shortening at the product development period. This system cooperates with two or more evaluation tools to evaluate BOM. The requirement to cooperate is the following. (1) The evaluation operation can be automated. (2) When the problem is found, the design improvement can be supported. (3) The registered evaluation can regularly be executed. The case and the effect of applying this system to the design work of the IT equipment are shown.

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This paper discusses that traditionally engineers have paid efforts to develop products, but from now on they must pay more attention to the creation of market, because if we compete on the traditional market, the possibility of winning there would be very low. But if we could create a new market, the winner takes all can be realized. And indeed if we recall that it is the engineer's fundamental task to create something, the target of our creation could be market.

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Up to now, industrialization is for satisfying the people's needs. But what increasing diversification implies is the fact that we all live different life and these difference of how we lives our lives cause the difference of value. So to really cope with the diversification, we have to take into account how people live their lives. And how they lived their lives is nothing other than the memories they have. Thus, to meet the diversifying needs is nothing other than to consider the memories of the people. In fact, such a phenomenon as imprinting is well known. And McDonald is famous for imprinting their taste into the children. Therefore, how we can industrialize our memories is a big challenge in the industrial sector today.

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This paper poses a question: If design with more user involvement will come in and the functions of systems grow with time during their life cycles, would the present framework of Japanese laws be applicable? The current framework of Japanese laws is based upon the civic law, or the written law. But technology evolves with time. Then, how would laws adapt to such changes? The present framework of law is more deductive than inductive. But if such changes in design will come into reality, would it not be true that inductive framework be more effective?

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English uses different verbs for describing different situations, while Japanese uses the same verb for different situations. But in QFD, Quality Function Deployment, this difference of languages is not well discussed. But if we note that Japanese use the same verb for many different situations, Japanese use adverbs or onomatopoeia (sound effect words) to describe the situation. Thus, QFD should take into consideration such difference of languages to really describe the design requirements.

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This paper points out that the framework of design is changing rapidly to incorporate user's judgment, decision and actions more and more, while the user in the traditional design have been expected to perform as the designer intended. And the fusion of software and hardware is quickly progressing. The quality problem of software is how we can tell its life is over. Thus, when we come to think that more and more human and software aspects are coming into design, it is a big challenge for us engineers how to define and secure quality of such hardware and software combined systems.

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The future systems are believed to be moving toward human driven, system support direction, because the situations change so rapidly and so widely that the user's understanding of the situation plays a crucial role in operating a system. And such systems which support the action of the human, rather than a human supports the operation of a system. In such an age, communication between human and a system will become more and more important. This paper discusses what kind of issues are foreseen in such an age when we consider quality

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The relationship between quality of a machine or system and sound has not been discussed much. This is not the discussion of the quality of sound. There are great deal of work done in the area of how we should define and secure the quality of a sound. But when the sound of a machine or a system is discussed with relation to sound, in most of the cases it is how we can predict the failure of a machine or a system or in the similar area in the operational stage. To our knowledge, it seems very few work has been done in terms of how the quality of a machine or a system can be audible at the stage of design. There are many publications pointing to the necessity of and importance of visualizing the design intent or design images. But when we come to think that our five senses are cross modal and we can hear what we see and we can see what we hear, there must be a way to make our design audible.

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