We proposed the form-generation system for obtaining diverse forms in order to support designing in early design process. The system consists of the form-generation division and the GA operation division. GA in the system has some features for obtaining diverse solutions. And cellular automata were expanded into 3D form-generation. Moreover, the system was applied to chair design in order to verify the effectiveness of the system. As a result, diverse chair forms were obtained through the system. Then, the diversity index of forms and the number of trial forms were defined in order to evaluate diversity of forms and efficiency of the system. By using these indices, it was confirmed that the system could be efficient in comparison with other algorithms and could obtain as same diversity as random search algorithm. Thus we showed the possibility applying the system to design of artifacts.

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Recent remarkable changes on design environment, such as concurrent engineering matter, environmental problem, consumption trends and information network, are pointed out. A new concept of 3D-CAD system in proportion to the changes is proposed. The concept is agent oriented approach with attribute information of solid.

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It has not been established how to express dimensions and dimensional tolerances in the 3D-CAD systems. This paper proposes a method for the expression of those values. In this study, dimensions are expressed by the plane element with color in order to make the distinction between some datums of many dimensions. The dimensional tolerances are also expressed by changing the color concentration of the plane element along the tolerance value. The proposed method is easy to realize that what dimensions and dimensional tolerances are expressed, since concepts of plane element and changing the color concentration are intuitively.

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This paper proposes a method for obtaining reduced polygon model in 3D scanning. In this method, sensor fusion scheme is employed to find the sampling points of object's surface, which are defined as the boundary of surface normal and color. These sampling points are the vertices of basic polygons. The reduced polygon model is constructed by merging smooth and same colored polygons. The efficiency and feasibility of this method is discussed through the experimental results.

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This paper is to introduce the concept of "two-sided" shape in solid modeling. The two-sided shape can represent sheet metal plates in natural manner, and it can be widely used in automobile parts design, for example. The authors propose a rounding (filleting) robust algorithm for two-sided shape in parametric solid modeling.

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We have been developing a CAM system of foam polystyrene by using an industrial robot carrying a tool with a heated blade. This system creates a process plan for a given shape based on the operator's command, checks it by simulating the motion of tool, and generates motion commands for the robot. In previous paper we had reported the system which creates 2.5 dimensional shapes. In this paper, a new system is described for 3 dimensional shapes using a new tool with a stick-type blade. Experiments were made to investigate the characteristics of the tool and the result was reflected to the robot motion program.

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In order to generate realistic virtual world, sound display system which can represent high presence 3D sound field is necessary. We developed 3D sound display system based on acoustic simulation, and implemented it with the immersive projection display CABIN. By using this system, we can realize-real-time and interactive control of 3D sound field, and virtual sound source can move in the virtual world. This paper describes the system configuration, an algorithm of making sound field filter, and the experiment on evaluating this algorithm.

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This paper describes a presentation method of surface textures to both visual and haptic sensations. In this system, the image of textures is projected onto a screen which is attached to a top plate of a texture display. The texture display conveys a vibratory stimulus to the user's fingertip that is placed on a pin-array, which is related to the projected textures. A position measurement device was newly implemented by using a link mechanism in order to obtain the absolute position and orientation of the texture display. The structure of the whole system is presented followed by a brief description of evaluation and future work.

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This paper describes a method for rendering of tactile texture by a haptic display. The height variation of a surface is substituted by the fluctuated coefficient of friction on a planar surface to alleviate to alleviate the amount the amount of calculation introduced by complicated geometry. The coefficient of friction is calculated from a local gradient of a surface height map. For adding a sensation of perpendicular force variation, a surface normal force is augmented by the amount of height at the contact point. We set three parameters which are needed to control the behavior of the calculate model. The parameter of frictional component decreased as cylinder diameter increased, and the parameter for height value about with the diameter of a cylinder. Then evaluation of this method by using the geometrical model of textures is discussed.

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Many kinds of haptic devices which applied parallel-rink, wire tension and so on has been developed. But the visual display souch as CRT or single screen display is used with the haptic devices. In this paper, we developed a immersive projection display which can be effectively used with the haptic device, and we propose the forth grid which sists direct manipulaton to the 3D objects. By using it, we evaluated several forth feedback patterns and accuracy of 3D pointing. The result suggests that the forth grid is a good user interface for 3D direct manipulation.

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In this paper, the development of a VR system called HapticWorkBench and the evaluation of the system usability are reported. The HapticWorkBench consists of a wide-screen stereoscopic visual display based on Immersive Projection Technology and a force display. We employed a wearable force feedback device called HapticGEAR to provide a wide working area to the user. We performed an experiment to simulate is simple assembling task where the sensation of touch on objects, the collision between parts, and the weight of holding components are fed back to the user through the force display. In conclusion, we proved the force sensation provides the efficiency of the task.

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This paper describes an arrayed fore display that presents kinetic rigidity distribution. The device simulates hard objects underneath a soft surface. This device employs an elastic surface made of rubber and sponge. An array of linear actuators is set under the surface. Pressing the elastic body by the actuators, the rigidity distribution of the surface can be changed. We analyze the performance of the device through measurements of rigidity and psychophysical tests.

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When designing systems that support remote instruction on physical tasks, one must consider requirements : 1) participants should be able to use non-verbal expressions, 2) they must be able to take an appropriate body arrangement to see and show gestures, 3) the instructor should be able to monitor operators and objects, 4) they must be able to organize the arrangement of bodies and tools and gestural expression sequentially and interactively. GestureMan was developed to satisfy these four requirements by using a mobile robot that embodies a remote instructor's actions. The mobile robot mounts a camera and a remote control laser pointer on it. Based on the experiments with the system we discuss the advantage and disadvantage of the current implementation.

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According to the recent rapid progress of high performance computing, aerodynamic design methodology based largely on CFD (Computational Fluid Dynamics) is becoming an indispensable tool along with wind tunnel testing. In 1991,TRDI-JDA has started the "CASPER (Cmputational Aerodynamics System for Performance Evaluation and Research)" project together with major domestic aircraft manufactures, MHI, KHI and FHI. The CASPER was installed in 1998. We expect the CASPER to be very useful to develop high performance advanced fighter at the beginning of the 21st century. In this paper, we show evolution and highlights of hardware and software of the CASPER. For the CFD code validation, numerous flow computations of various aircraft and airfoil configurations are carried out on the CASPER and compared well to wind tunnel experiments. Providing CFD data for aeroelastic and flight simulation modules, the CASPER also has the potential for multidisciplinary CFD simulation. Some of our numerical results on the CASPER are presented.

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This paper proposes optimal design of flat structures for vibration suppression in mechanical systems. A flat structure is modeled by the finite element method, and the thickness of each element is considered as a design variable. The H_∝ norm o the transfer function from disturbance sources to the output points where vibration should be suppressed, is adopted as the objective function to represent the magnitude of vibration transfer. The genetic algorithm is employed for computation of the optimal solution under the constraint of the total mass. An example is given to demonstrate the effectiveness of the proposed design method.

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The development and widespread use of computer networks such as the Internet and corporate intranets has made possible the use of various types of information, contained in individual databases, in the field of design optimization. However, there is a crucial need for systems that can combine, integrate, and provide useful access to the wealth of information contained in such separate databases. This paper presents a methodology for searching, selecting, and unifying separate databases, by constructing a new type of master database. A key point in this methodology is the preservation of design-specific data in the constructed master database, so that, for example, structural features and design elements belonging to the design problem are included. The merit is that wide-ranging informational searching becomes possible, using more abstract retrieval conditions. Specifically, it becomes possible to search not only for data values, but also for design problem components. An applied example is given, concerning calculations for a 2-degree of freedom robot arm design optimization. After the construction of a master database based on this paper's methodology and integration with data acquired by searching other databases, an optimal design is achieved by calculations based on genetic algorithms. Additional processing procedures are performed to exploit the advantages of unified databases.

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This paper proposes a concept of layout design automation by focusing on hierarchy in functional and spatial structures of a system such as an energy plant. This concept is based on the emergent synthesis that any design solution is generated through interactions between the whole and parts. Under its methodology, various elements that compose a layout design problem such as layout components, their partial sets, layout space and layout conditions are respectively modeled as independent autonomous agents. Layout design is deployed through recursive iteration of assumption of a tentative layout, recognition of partial situations for individual agents, their evaluation and layout refinement. In this process such situations are dynamically and reflexively formed through various interactions among agents. This methodology for computational design is applied to a prototype system for plant layout design in order to demonstrate its promises and possibilities.

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Consumer products are deployed from market-in stage through growing-up stage to maturated stage by gradually shifting their appealing features from fundamental functions to supplemental value-addition over their life stages. This paper investigates the underlying design patterns in such product deployment and proposes an design assessment method toward superior product definition. Product definition means here the objective establishment for respective modules and their features before executing actual design activities. The method is based on quality function deployment (QFD), cost-and-worth assessment in value engineering, cost estimation methods and the revealed patterns, Its validity and effectiveness are ascertained through the analysis of design changes across three different vacuum cleaners for Japanese market in the last three decades.

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The two measures of modularity, defined and proposed here, are indicators for quantitative evaluation of merits and demerits of the design. The first measure to modularity evaluates the grade of desirable combination of module constituents. Well-designed module shows the good effect on resource circulation, and the module may be handled as one element. This is the reduction of elements number in effect by introducing modules. There are many feasible processing methods of used industrial products such as disassembly, decomposition, fractionation, incineration, and landfill. If the way of process onto every constituent of the module is same, there is no necessity to decompose the module into smaller elements. The second measure of modularity is an indicator of compromising level of module constituent properties with the functions. Module structure and combination of elements are strongly depending upon the functions of products, because every element has a proper function to play its roll under some restrictions at assigned location in a product.

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The relationship between installation numbers of micro gas turbine cogeneration units and maximum energy demands is investigated using an optimization method. Design variables such as equipment capacities and utility maximum contract demands are determined together with the system's operational strategies so as to minimize the annual total cost subject to satisfaction of energy demand requirement. Based on the annual total cost evaluated by the optimal design planning, a maximum energy demand at which the optimal installation number changes is obtained from an economic viewpoint. Numerical studies are carried out on micro gas turbine cogeneration systems installed in hotels with several heat to power ratios of maximum energy demands. Through the studies, a map expressing the relationship between the optimal installation numbers and the maximum energy demands is illustrated, and the economic feasibility of micro gas turbine cogeneration units is clarified.

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