Parisa Ghodous

CAD/CAPP Integration using Feature Ontology

In a collaborative computer-supported engineering environment, the interoperation of various applications will need a representation that goes beyond the current geometry-based representation, which is inadequate for capturing semantic information. The primary purpose of this study is to discuss a semantically based information exchange protocol that will facilitate seamless interoperability among current and next generation computer-aided design systems (CAD) and between CAD and other systems that use product data. An ontological approach is described to integrating computer-aided design (CAD) and computer-aided process planning (CAPP). Two commercial software applications are used to demonstrate the approach. This involves the development of a shared ontology and domain specific ontologies in the Knowledge Interchange Format (KIF) language. Domain specific ontologies — which are feature-based — are developed after a detailed analysis of the CAD and the CAPP software. Mapping between the domain ontologies and the shared ontology is achieved by several mapping rules. The approach is validated by using a variety of parts.

Product Family Manufacturing Plan Generation and Classification

In the concurrent engineering approach, the problems related to product fabrication are taken into account as early as possi ble in design process. Manufacturing and assembly process design are decisive and expensive processes conditioning all the future steps of industrialisation and fabrication. In this paper a new method for assembly plan generation, based on the concept of meta-prod uct, is presented. This method is designed for modern production environments that are organised in product families with multiple op tions and variants. Facing the combinatory explosion problem, the method proposes an original representation of assembly sequences allowing the generation of a minimal list of non-redundant assembly plans called meta-sequences. In this method, an optimal assembly sequence class is selected. Then, for each product variant an optimal specific plan class is deduced from a simple analysis of product variants components. An assembly reactive control system, adapting this optimal solution to the real assembly workshop conditions is also proposed. Another competitive problem is the case of production of old or short-series products. To rationalise their manufacturing, a solution consists in classifying products into classes, on the basis of similarity of required manufacturing processes. This technique called group technology (GT) helps to minimize unnecessary variety of products in a manufacturing plant by making designers aware of existing simi lar components. In this paper a new GT method is presented. It allows the classification of sequential manufacturing sequences as well as tree-like manufacturing plans. The method is based on an adapted representation of tree-like manufacturing plans, the distance adapted to this special case, efficient heuristics, and hierarchical bottom-up classification. Then, each product class can be managed in accordance to our family product generation method, or can be served as a base for reengineering process of firms range of products.

Conflict mitigation in collaborative design

Conflict management is an unavoidable stage of the collaborative design process. We assume that classifying conflict causes can help conflict prevention as well as detection and resolution strategies. Our approach proposes a crossed classification of conflict causes and the correspondent mitigation strategies and implements this classification in order to enable conflict detection in the earlier phases of the design process. Emphasis is put on capture and use of design rationale and knowledge to help conflict mitigation. Based on this approach, a conflict mitigation module integrated in an advanced architecture for concurrent design and manufacturing is presented. A case study on the design of an electric connector illustrates the use of this module.

A Generic and Synchronous Ontology-based Architecture for Collaborative Design

Today’s complex design projects require teams of designers to come together to facilitate the sharing of their respective expertise in order to produce effective design solutions. Due to the increasing need for exchanging knowledge, modern design projects are even more structured to work with virtual distributed teams that collaborate over computer networks to achieve global optima in design. This article presents an architecture where collaborative design is synchronously and generically achieved. That is, where particular representation models are transformed into ontology instances and merged together in order to accomplish the final product design. It is a synchronous approach because the merging process is undertaken at the same time that interaction among designers takes place. As supporting technologies, Web Ontology Language and Web Services are used to implement such an architecture.

Semantic interoperability of knowledge in feature-based CAD models

Dans un environnement collaboratif de developpement de produit, plusieurs acteurs, ayant differents points de vue et intervenant dans plusieurs phases du cycle de vie de produit, doivent communiquer et echanger des connaissances entre eux. Ces connaissances, existant sous differents formats heterogenes, incluent potentiellement plusieurs concepts tels que l’historique de conception, la structure du produit, les features, les parametres, les contraintes, et d’autres informations sur le produit. Les exigences industrielles de reduction du temps et du cout de production necessitent l’amelioration de l’interoperabilite semantique entre les differents processus de developpement afin de surmonter ces problemes d’heterogeneite tant au niveau syntaxique, structurel, que semantique. Dans le domaine de la CAO, la plupart des methodes existantes pour l’echange de donnees d’un modele de produit sont, effectivement, basees sur le transfert des donnees geometriques. Cependant, ces donnees ne sont pas suffisantes pour saisir la semantique des donnees, telle que l’intention de conception, ainsi que l’edition des modeles apres leur echange. De ce fait, nous nous sommes interesses a l’echange des modeles « intelligents », autrement dit, definis en termes d’historique de construction, de fonctions intelligentes de conception appelees features, y compris les parametres et les contraintes. L’objectif de notre these est de concevoir des methodes permettant d’ameliorer l’interoperabilite semantique des systemes CAO moyennant les technologies du Web Semantique comme les ontologies OWL DL et le langage des regles SWRL. Nous avons donc elabore une approche d’echange basee sur une ontologie commune de features de conception, que nous avons appelee CDFO « Common Design Features Ontology », servant d’intermediaire entre les differents systemes CAO. Cette approche s’appuie principalement sur deux grandes etapes. La premiere etape consiste en une homogeneisation des formats de representation des modeles CAO vers un format pivot, en l’occurrence OWL DL. Cette homogeneisation sert a traiter les heterogeneites syntaxiques entre les formats des modeles. La deuxieme etape consiste a definir des regles permettant la mise en correspondance semantique entre les ontologies d’application de CAO et notre ontologie commune. Cette methode de mise en correspondance se base principalement, d’une part, sur la definition explicite des axiomes et des regles de correspondance permettant l’alignement des entites de differentes ontologies, et d’autre part sur la reconnaissance automatique des correspondances semantiques supplementaires a l’aide des capacites de raisonnement fournies par les moteurs d’inference bases sur les logiques de description. Enfin, notre methode de mise en correspondance est enrichie par le developpement d’une methode de calcul de similarite semantique appropriee pour le langage OWL DL, qui repose principalement sur les composants des entites en question tels que leur description et leur contexte.

Product Data Exchange Using Ontologies

In the design anywhere manufacture anywhere paradigm, we need to have appropriate mechanisms for communicating design information to manufacturing software, in particular process planning. This is in addition to CAD-CAD interoperability. However, in current industrial practice, conceptual design, process/resource selection, time/cost estimation, detailed design, and process planning are performed independently, without integrated software tools. Design and manufacturing data and messages cannot be efficiently sent from one system to another. Interoperability is further complicated as we need to communicate between different domains (in contrast to CAD-CAD interoperability). In this paper, we first review the existing methods for product data exchange. Then we describe a new approach which improves the data exchange by taking into account the semantics of data. This approach is based on ontologies, which allows the formalization of concepts related to product development in an appropriate context. Finally, we verify this approach for two commercial software tools in the framework of design and process planning data exchange.

Service-based negotiation for advanced collaboration in enterprise networks

Information systems support organisations to achieve greater efficiency by automating their activities. Nowadays, in the actual competitive and global business context, the advent of enterprise networking has been challenging collaboration, coordination and continuous interactions among dissimilar information systems to adapt and improve them. Sustainability of interoperability among heterogeneous systems regarding sharing information and knowledge in a collaborative dynamic environment is hard to achieve and maintain. This paper proposes a service-based negotiation framework for advanced collaboration in enterprise networks, as a solution to improve the sustainability of interoperability within enterprise information systems. Validation in industrial scenario is presented and discussed.

EXPRESS to OWL morphism: making possible to enrich ISO10303 Modules

ISO10303 STEP has been acknowledged by the world’s largest industrial companies, as the most important family of standards for the integration and exchange of product data under manufacturing domains. With the advent of globalization, smaller enterprises (SMEs) looking to level up with world-class competitors and raise their effectiveness are also realizing the importance of the usage of this kind of standards. However, to enable a model-based interoperability, STEP industrial standards, the Application Protocols (APs) follow a modular approach, i.e. they are composed by a set of generic purpose modules sharable by a number of different APs. This way, the core STEP reference models contain vague definitions that sometimes raise ambiguous interpretations. A possible solution to overcome this barrier would be to add further semantics to the concepts defined and enable STEP modules as ontologies, thus providing an alternative to traditional implementations. SMEs can benefit even more from this alternative, since OWL is currently a widespread technology, with abundant low cost supporting tools comparing to the ones dealing directly with STEP.

Resolving Interoperability in Concurrent Engineering

To face an increasingly competitive environment within a globalization context, and to focus on core high-added value business activities, enterprises have to establish partnerships with other companies specialized in complementary domains. Such an approach, primarily based on optimization of the value chain, is called virtualization of the Enterprise. Enterprises relying on virtualization, sub-contracting and outsourcing have to coordinate activities of all the partners, to integrate the results of their activities, to manage federated information coming from the different implied information systems and to re-package them as a product for the clients. The adopted organization, which is considering as well as the internal and external resources, is called “Extended Enterprise”. Nevertheless, in such complex emerging networked organizations, it is more and more challenging to be able to interchange, to share and to manage internal and external resources such as digital information, digital services and computer-enacted processes. In addition, digital artifacts produced by enterprise activities are more and more heterogeneous and complex. After characterizing expected interoperability for collaborative platform systems and highlighting interoperability issues and brakes not yet addressed, this chapter describes an innovative approach to build interoperability based on a Federated Framework of legacy eBusiness standards of a given ecosystem. It implies facing important issues related to semantic preservation along the lifecycle of the artifacts and infrastructures required to define and exploit an application. We present two use case studies that apply interoperability strategies.

Collaborative negotiation for ontology-driven enterprise businesses

The requirements from a globalised world demand that enterprises not only shift their paradigm from product-centrism to component-centrism on integrated products, potentiating the need for tight interoperability dependencies, but also that the product specifications and concepts are fully understood by customers and providers in a transparent manner that surpasses the barriers of language, culture and technology. This paper presents the NEGOSEIO framework, which enables service-based interoperability between parties, closely integrated with semantics and business understanding via the use of reference ontologies in the quest for achieving a stronger interoperability liaison. The papers validation and discussion is performed in its application on the ontology negotiation of business environments in the scope of the EU-funded FP7 project TIMBUS for digital preservation of resources and enduring business continuity.