Kazuhiro Aoyama

Product Behavior and Topological Structure Design System by Step-by-Step Decomposition

This paper proposes new design methodology, which enables a designer to generate a product behavior and topological structure based on step-by-step decomposition keeping their interdependency. In a development process of an industrial product, it is very important for designers to have enough consideration for the product behaviors. If some unexpected product-behaviors are overlooked, product-functions could be badly affected or catastrophically lost in the worst case. The authors show the effectiveness of the step-by-step decomposing process by applying the example of stapler design. Three critical issues of system implementation are addressed: (1) a product information model, which is able to describe behaviors and topological structure of a product, (2) a design process model for step-by-step decomposition keeping their interdependency, (3) procedures to evaluate the product dependability with taking normal component failure into consideration.Copyright

An Integrated Model of Product, Production Process and Quality Information for Failure Prediction

This study proposes a methodology for predicting product failures occurring due to known failures and causalities. The prediction is based on failure propagation in an integrated model of a product, production process, and quality information (PPQ). This methodology enables a designer to predict new failures. One of the concepts for failure prediction is the PPQ for compiling referring to quality-related issues. The other is an analysis methodology of the failure propagation for predicting new PPQ-based failures. The failure propagation indicates the possible failures from the production process and their causes. Three critical issues for system implementation are discussed in detail: 1) integrated PPQ model; 2) methodology for knowledge reuse by developing a PPQ-based library, and 3) an analysis methodology for failure prediction. The prototype system of the PPQ model is implemented for failure prediction in the example of a production system of Auto-Breaker.Copyright

A Search Algorithm of Interface Structure to Achieve Required Product Behavior

The design of interactions of product components, i.e., an interface structure, is a very difficult design problem, because the whole product behavior is determined by the interface structure. This paper proposes a new algorithm that can be used to derive the interface structure automatically to achieve the required product behaviors. Generally, two or more different design proposals can achieve the same required product behavior. Therefore, the designer must select the better design proposal based on consideration of both cost and mechanical constraints. To support the evaluation, decision, and selection by the designer, an evaluation method for product behavior by comparison of the required product behavior is proposed. We call this methodology the design system of Product Behavior by automatic calculation of the Interface Structure (PBIS). Here, we demonstrated the effectiveness of the PBIS algorithm in an implemented prototype system. PBIS enables the designer to determine the interface structure interactively based on a list of proposed interface structures that can realize the required product behavior. The methodology addresses: (1) how the interface structure problem should be formulated; (2) how the algorithm for automatic proposition of the interface structure achieves the required product behaviors; and (3) the evaluation method of the interface structure by comparison between the required product behavior and achieved product behavior.© 2005 ASME

System-Level Design Tools Utilizing OPM and Modelica

This paper presents a methodology and tools to synthesize and assess different System-Level Designs. It utilizes the descriptive modeling language Object Process Methodology (OPM) to hierarchically describe the functionality of the System of Interest which is mapped by way of various intermediary models to an architecture in the Modelica numerical modeling language. The resulting Modelica architecture model is subsequently used as a framework for the rapid creation of alternative System of Interest designs by the variation of components. To enable consistent assessment of the alternatives, Assessment Scenarios are created based on the functionality identified by OPM decomposition. By defining a hierarchy of Modelica models with the Assessment Scenarios at the top, all the System of Interest alternative models can be composed into the Assessment Scenarios and the resulting models simulated. With a combined score for each alternative across all the Assessment Scenarios being computed by way of Multi Objective Decision Analysis (MODA). This paper demonstrates the approach with an actual student solar powered autonomous boat development project.

Supporting System for Tour Lineup Design based on Tour Service Modeling

This paper proposes a computer aided design method of package tours that meets various tourists’ favors while controlling cost. Tour service is modeled as network that comprises activity, place, capability and enabler. Design process of a tour lineup takes three steps. First, the network is redesigned by morphing an improvement. All possible sequences of activities (tour candidates) are extracted from the network. The extracted tour candidates are combined as a lineup. After feasibility of the lineup is checked, it is evaluated by the viewpoints of tourists and providers. The proposed method is validated through the case of Tokyo day tours.

MODULAR DESIGN METHOD FOR SUSTAINABLE LIFE-CYCLE OF PRODUCT FAMILY CONSIDERING FUTURE MARKET CHANGES

A modular design is effective method in order to keep coexistence of environmental consciousness and variety of product. However, the lifecycle time is very long, so that a market could change greatly in the meantime. This is one of the major reasons that a judgment of a good or bad modular structure is not easy for the designer. In order to solve this problem, two methodologies are required: (1) a prediction method of the change of the market in long life span of the product family, and (2) a design method of the life-cycle and module structure based on the predicted market change. The aim of this research is to develop a method of the ability to design the optimal modular structure considering life-cycle calculation based on the sales scenario defined by the plan and prediction of the sales of the line-up products in the product family. This paper assumed that the market change is modeled as a number of the sold product. Based on this assumption and change of the quantity of the sales products by the change of the customer requirements and the competitive products in market are modeled as a sales scenario of a product family. An example is validated for effectiveness of the proposed method based on the proto-type system.

Life-cycle simulation model for large scale welded structure-a basic study on welded joint model with consideration of the welded joint corrosion

Corrosion of the welded joint has been singled out as a main cause of damage to ships. Insufficient maintenance of ships causes severe accidents due to the deterioration of products. These accidents lead to serious problems ranging from environmental pollution caused by oil spills to loss of lives. In order to prevent such accidents, we should design the products life cycle before designing the product, evaluate the life of the product, and make effective maintenance plans by computer simulation. Additionally, we should think of realizing the best product design front the viewpoint of life-cycle management. This paper presents a welded joint model that considers the effect of corrosion of the welded joint of a ship structure and presents a scenario for the collapse of a ship. In addition, a simulation method for evaluating product deterioration by corrosion of the welded joint is shown. In order to support a life-cycle design that takes corrosion into account, the authors have implemented a life-cycle simulation system based on a product model for computer-aided design and production.

Implementing Value-Driven Design in Modelica for a Racing Solar Boat

Research has shown that current design approaches, such as requirement-based design or cost as independent variable (CAIV), may fundamentally yield suboptimal designs. In response to the need for better systems, new design techniques that are based on optimization and decision-making have been proposed. In this paper, we show how Modelica can be used to implement and operationalize value-driven design (VDD) in concept selection. Modelica’s object-oriented strengths are employed to model design alternatives and its capability to execute Monte Carlo simulation enables the introduction of uncertainty in models and assessment. The proposed approach has been applied to the conceptual design of an unmanned, autonomous solar powered boat, which is aimed at racing in a student competition. Value has been defined as a function of the probability to win the said race, which expands usual examples of value functions to nonmonetary ones. This paper describes the approach as well as the benefits, limitations, and obstacles encountered during its implementation.

Service Data Model in Design Support System for Sightseeing Tours

This paper proposes a data structure definition of the tourism resources that will help tour designers determine tourists’ fundamental needs based on their requests and design their tours more efficiently. This study analyzes tour services and divides the information useful in proposing services, based on tourists’ requests, into three types: geographical, time, and meaning information. This paper employs those three types of information to define two indexes for use in proposing services that match customer requests.

Present Situation of Customer Participation in Service Design and Production - Interviewing Tour Agent, Airline and Elevator Maintenance Company -

This paper validates the assumption that customer participation in mass customization, based on modularization, inspection, and configuration, is effective in the design and production of a service. This validation is based on interviews conducted with a number of industrial companies. These companies included a tour agent, an airline company, and an elevator maintenance company. The interview results showed that the current level of customer participation is insufficient. This study concludes that there are significant opportunities to apply modular and masscustomization methodologies to support customer participation and to realize customer-oriented service design and production.