Michel Ferney

Configurable product design using multiple fuzzy models.

The present economic environment is characterized by increasing market demands for customized products. Configurable product design or design for configuration represents the solution for the new market challenges. Configurable product design is complex. The development of a methodology of design for configuration must take into account the different views of the product that occur during the design process, the great number of product variants that can be generated and also the customer-oriented characteristic of the configurable products. Moreover, the design for configuration must represent and manipulate the uncertainty throughout all design stages. This paper proposes the development of an integrated approach of configurable product design based on multiple fuzzy models. The transition from customer specifications into physical solutions is performed by the help of multiple fuzzy models: the fuzzy product specification model, the fuzzy functional network, the fuzzy physical solution model and the fuzzy constraint model. The degrees of interactions between product functions defined in the fuzzy functional network can vary according to the functional structure chosen by a customer. This may lead to different functional structures of the product and, consequently, to different alternatives of physical solutions. After the set of satisfying physical solutions is determined, the fuzzy constraint model is applied to determine the valid set of solutions. An application that illustrates the proposed approach is developed at the end of the paper.

Fuzzy agents for product configuration in collaborative and distributed design process

Design for product configuration is an inherent collaborative and distributed process. It is characterised by fuzziness of information, fuzziness of knowledge and fuzziness of interactions. Designs for configuration organisations are heterogeneous, dynamic and fuzzy evolving systems. This paper proposes a fuzzy agent-based approach to assist the product configuration. Four heterogeneous and distributed domains: (a) requirement, (b) functional, (c) solution and (d) constraint, are considered. Based on the distributed fuzzy models, fuzziness of interactions, a fuzzy computational approach for product configuration is developed. Agentification of the configuration approach, modelling and the implementation of a multiagent system, are presented. The fuzzy consensual solution agents emerge from fuzzy interactions of fuzzy distributed agents. The optimal product configuration emerges from affinities of the fuzzy consensual solution agents. A case study is presented to demonstrate the potential of this approach.

A fuzzy configuration multi-agent approach for product family modelling in conceptual design

Product modelling is an essential issue in the configurable product design. Many attempts have been made for modelling the configurable products. However, most of conducted research considers the configurable product modelling as an arrangement problem of a predefined set of components into a valid product structure. This paper considers configuration not only as a structural problem but also as a collaborative design problem. Product configuration must consider explicitly different actors and their perspectives influencing simultaneously the design of configurable products. Solving product configuration problems requires collaboration of actors from multiple distributed views. Therefore, from process and product point of views, engineering design of configurable products can be assisted by multi-agents systems. Following up this consideration, this paper proposes a Fuzzy Configuration Grammar based agents to assist collaborative and distributed design for configuration. Based on the distributed fuzzy models, fuzziness of interactions during the collaborative and distributed design for configuration, a computational approach for product configuration is developed. Modelling and implementation of an agent-based system, called G-APIC (Grammars based Agents for Product Integrated Configuration), is presented. In this agent-based system, there are four communities of agents: requirement community of agents, function community of agents, physical solution community of agents and process constraint community of agents. A fuzzy set of consensual physical solution agents, a sub community of alternative physical solution agents satisfying both customer’s requirements and different process views constraints, emerges from intra and inter-communities interactions of agents. Then, the proposed Fuzzy Configuration Grammar allows the interactions between these fuzzy consensual solution agents. The optimal product configuration, a fuzzy set of interacted consensual solution agents, emerges from these interactions. A case study illustrates the proposed approach.

A Fractal-Based Approach for Concurrent Engineering:

The successful application of concurrent engineering in industry should be based on the effective organization of different activities, from design to marketing. However the dynamics of the environment has raised the following question: what model can be applied for concurrent engineering? This paper presents three models for concurrent engineering organizations. The models are based on the concept of autonomous design units, which are formed using the fractals characteristics: self-similarity, self-organization, and dynamic. These models allow one to reorganize the design process and to understand the dynamics of the concurrent engineering organization. The application taken from the French automotive industry shows the characteristics of these models.

Fuzzy Approach for Maintainability Evaluation in the Design Process

The maintainability aspect of some complex products has a significant role during the life cycle; it is the design attribute determining the performance of various maintenance activities such as: inspection, diagnosis, repair, and replacement. If a product has poor maintainability, the maintenance activities which have to be performed on it during its life cycle are difficult, increasing the costs, and also the time required to accomplish the maintenance tasks. An early evaluation of maintainability during the design process may help the designers to make educated design choices, also from the maintenance point of view. In this article, we present a maintainability evaluation approach based on fuzzy logic; fuzzy linguistic variables are employed in order to represent and handle the design data available early in the design process. The main reason for employing fuzzy logic principles for maintainability evaluation is the imprecision and uncertainty generally characterizing the design data available at the beginning of the design process, when design specifications and requirements are subject to change and the description of the design is incomplete. The measure of the product maintainability or maintainability index might be expressed by a fuzzy numerical value computed as the weighted mean of the criteria values used for the evaluation.

Feature modeling using a grammar representation approach

In intelligent computer-aided design the concept of intelligence is related to that of integration. Using feature-based computer-aided design models is thought to make a complete integration. This paper presents a feature recognition approach based on the use of a feature grammar. Given the complexity of feature recognition in interactions, the basic idea of the approach is to find the latent and logical structure of features in interaction. The approach includes five main phases. The first phase, called regioning, identifies the potential zones for the birth of features. The second phase, called virtual extension, builds links and virtual faces. The third phase, called structuring, transforms the region into a structure compatible with the structure of the features represented by the feature grammar. The fourth phase, called Identification, identifies the features in these zones. The fifth phase, called modeling, represents the model by features. The feature modeling system software is developed based on this approach.

An e-collaborative learning environment based on dynamic workflow system

In this paper, we present a DSC (Dynamic Shared Context) model which bases on collaborative learning environment. Firstly, we present the DSC methodology. This is a way to measure the relevance between events and roles in the collaborative environment. We can share the most appropriate event information for each specific role with this measurement. Then, we apply and verify this method in our project with Google App supported E-learning collaborative environment. Most kinds of events in collaborative learning activities can be supported and adequately shared in this environment.

Configuration Grammars: Powerful Tools for Product Modelling in CAD Systems

Engineering design synthesis is considered a formal one, when it is computable, structured and rigorous. Therefore, a design synthesis approach must rely on adequate product descriptions and representations, and also on effective, formal and structured tools and methods. In this paper we propose a product modelling and representation approach based on configuration grammars. Based on the properties of CAD configuration models, a generic configuration grammar is proposed. The representation by proposed grammar yields configurations composed of primitive elements or primitive configuration features, whose meaning is related to the engineering basic structures. Interconnection of these primitive configuration features describes a structural configuration. The proposed grammars are based on feature-component-module-product relationships, considered as adequate structural means for a general product representation. The proposed grammar based configuration modelling approach is validated by some applications.

Fuzzy Product Configuration in Advanced CAD Systems

Today, configuring the mechanical systems and their components correctly so that they meet their functions efficiently and can be easily manufactured and assembled is crucial to effective product design. However, currently there exists no systematic and effective method for designing configurations. This paper proposes and develops a formal representation for supporting the computer-aided design approach for configuration. Two interrelated questions are taken into account: 1. What are configuration features? (Configuration feature concept); 2. How can be constructed the design procedures capable to configure the product? (Computer-aided design approach for configuration). This approach, under the guide of the proposed formal representation, has been implemented in computers by using the functions of current CAD software.

A Grammar Based Approach for Feature Modelling in CAD

This paper presents a feature recognition method based on the use of a Feature Grammar. Given the complexity of feature recognition in interactions, the basic idea of the method is to find the latent and logical structure of features in interaction. The method includes five main phases. The first phase, called Regioning, identifies the potential zones for the birth of features. The second phase, called Virtual Extension, builds links and virtual faces. The third phase, called Structuring, transforms the region into a structure compatible with the structure of the features represented by the Feature Grammar. The fourth phase, called Identification, identifies the features in these zones. The fifth phase, called Modeling, represents the model by features. The FMS software (Feature Modeling System) is developed based on this method