Frédéric Demoly

Integrated product relationships management: a model to enable concurrent product design and assembly sequence planning

The paper describes a novel approach to product relationships management in the context of concurrent engineering and product lifecycle management (PLM). Current industrial practices in product data management and manufacturing process management systems require better efficiency, flexibility, and sensitivity in managing product information at various levels of abstraction throughout its lifecycle. The aim of the proposed work is to manage vital yet complex and inherent product relationship information to enable concurrent product design and assembly sequence planning. Indeed, the definition of the product with its assembly sequence requires the management and the understanding of the numerous product relationships, ensuring consistency between the product and its components. This main objective stresses the relational design paradigm by focusing on product relationships along its lifecycle. This paper gives the detailed description of the background and models which highlight the need for a more efficient PLM approach. The proposed theoretical approach is then described in detail. A separate paper will focus on the implementation of the proposed approach in a PLM-based application, and an in-depth case study to evaluate the implementation of the novel approach will also be given.

Product relationships management enabler for concurrent engineering and product lifecycle management

The current competitive industrial context requires more flexible, intelligent and compact product lifecycles, especially in the product development process where several lifecycle issues have to be considered, so as to deliver lifecycle oriented products. This paper describes the application of a novel product relationships management approach, in the context of product lifecycle management (PLM), enabling concurrent product design and assembly sequence planning. Previous work has provided a foundation through a theoretical framework, enhanced by the paradigm of product relational design and management. This statement therefore highlights the concurrent and proactive aspect of assembly oriented design vision. Central to this approach is the establishment and implementation of a complex and multiple viewpoints of product development addressing various stakeholders design and assembly planning points of view. By establishing such comprehensive relationships and identifying related relationships among several lifecycle phases, it is then possible to undertake the product design and assembly phases concurrently. Specifically, the proposed work and its application enable the management of product relationship information at the interface of product-process data management techniques. Based on the theory, models and techniques such as described in previous work, the implementation of a new hub application called PEGASUS is then described. Also based on web service technology, PEGASUS can be considered as a mediator application and/or an enabler for PLM that externalises product relationships and enables the control of information flow with internal regulation procedures. The feasibility of the approach is justified and the associated benefits are reported with a mechanical assembly as a case study.

A formal ontology-based spatiotemporal mereotopology for integrated product design and assembly sequence planning

This paper introduces the development of a formal ontology based on spatiotemporal mereotopology in the context of integrated assembly design and sequence planning. The main objective is to make assembly information accessible and exploitable by information management systems and computer-aided X tools in order to support product architects and designers activities. Indeed product design information and knowledge as well as the related assembly sequence require a semantic and logical foundation in order to be managed consistently and processed proactively. In this context, product relationships are considered and described in the part-whole theory supported by mereology and its extension, mereotopology. Firstly, a literature survey on formalisms in assembly-oriented design, mereotopological theories and spatiotemporal ontologies is presented so as to highlight the current research issue. Then, a mathematical description approach of product relationships based on mereotopology and temporal relationships is introduced. Built on this, an ontological development of the proposed theory using description logic rules is proposed. Finally, a mechanical assembly, as a case study, is introduced to illustrate the relevance of the proposed ontology.

PLM-based approach for Assembly Process Engineering

The paper presents a methodology in the field of Design for Assembly (DFA) related to the Assembly Process Engineering (APE) and the Product Lifecycle Management (PLM). This method has been designed to develop assembly methods into a legacy web-based PLM prototype. It takes into consideration assembly constraints in the early phases of the product development process in compliance with concurrent engineering challenge. A racing car ground-link system from an experimental case study is introduced to illustrate the proposed approach.

A Spatiotemporal Mereotopology-Based Theory for Qualitative Description in Assembly Design and Sequence Planning

This paper presents a novel qualitative theory in the context of assembly-oriented design, which integrates assembly sequence planning in the early product design stages. Based on a brief literature review of current assembly design approaches and mereotopology-based theories, the authors propose to go beyond by defining their own mereotopological theory, therefore enabling the qualitative description of product-process information and knowledge. The proposed mereotopological theory provides a strong basis for describing spatial entities (product parts) changes over time and space by considering a region-based theory linking spatial, temporal and spatiotemporal dimensions. The main objective of such an approach is to provide a product design description by proactively considering its assembly sequence as early as possible in the product development so as to ensure information and knowledge consistency with preliminary information and later introduce a spatiotemporal reasoning layer.

Proactive Assembly Oriented Design Approach Based on the Deployment of Functional Requirements

Concurrent engineering and integrated design have been a major issue over the past two decades especially considering design for X stakes. This paper describes a new proposal of integrated product-process design approach in order to improve the efficiency and the robustness of the assembly process planning phase. The proposed method illustrates how to consider functional requirements and technical constraints as early as possible to improve design principles and define the best assembly sequences fulfilling these requirements. Lastly, the proposed research is applied on an aeronautic case study for illustrating the potential benefits of such an approach in terms of taking account of assembly knowledge in the early product development stages.

Towards a Knowledge-Intensive Framework for Top-Down Design Context Definition

This paper presents a skeleton-based modeling approach enabling the definition of a knowledge-intensive design context at the beginning of the embodiment design stage. The research introduces an analogy to the incubator concept by creating a suitable support along the design phase including CAD modeling. The main objective of the proposed approach is to integrate engineering information and knowledge in the early phases of the product development process in a top-down and seamless manner so as to provide a knowledge-based design context for designers. The fact of including a design context in the embodiment design phase will assist designers to make better-informed decisions and therefore linking what (technical entities and engineering data), why (rationale) and how (processes and functions). The concept of design incubator will be defined according to its function, behavior and structure (i.e. skeleton entities, functional surfaces, design spaces, parameters, knowledge and design requirements). The proposed design incubator ensures the knowledge delivery and engineering support at the right time. A case study has been carried out to demonstrate the developed method.

Proactive Engineering and PLM: Current Status and Research Challenges

This paper discusses about the evolution of Product Lifecycle Management (PLM) through the introduction of an emerging vision in engineering design, proactive engineering. Over the last two decades, engineering design has seen some relevant approaches covering sequential engineering and then concurrent engineering (CE). Indeed, this shift was required to encompass knowledge integration issue into product design stages. This has led to relevant approaches such as design for X, parametric design, PLM-based approaches, decision-making support and ontology-based approaches to name a few. Proactive engineering can be considered as an emerging engineering framework which integrates as early as possible lifecycle knowledge and technological constraints in product design and manage those knowledge in an integrated and harmonious manner. The fact of using lifecycle process knowledge as design context demands therefore the definition of downstream processes before defining he product geometry so as to overcome current limitations in CE oriented PLM approaches. Hence, with such stakes, understanding and awareness becomes crucial in PLM in order to deliver well-balanced products.

Towards an Harmonious and Integrated Management Approach for Lifecycle Planning

The paper presents an initiative towards the harmonious and integrated management of lifecycle planning, such as assembly planning, disassembly planning, maintenance planning and so on. This stake currently meets industrial requirements and research issues, mainly in product lifecycle management, integrated design, and lifecycle engineering fields. The fact of managing X planning during product design requires therefore a complete understanding of the product lifecycle processes and various abstraction layers of data-information-knowledge. In such a way, the critical outcome is to ensure the development of well-balanced product by considering the rationale of lifecycle planning and managing its related data, information and knowledge.

A Mereotopology-Based Approach for Integrated Assembly Modeling and Planning

This paper describes a novel approach for integrated assembly modeling and planning. The main objective is to make assembly information accessible and exploitable by data management systems and computer-aided X tools. Product information and knowledge as well as the related assembly sequence require a logical foundation in order to be managed consistently and processed proactively. In this context, the authors consider and describe product-process relationships in the part-whole theory supported by mereology and its extension, mereotopology. Firstly, past and current research work is presented on: concurrent product design and assembly sequence planning approaches; existing assembly relational models; and spatio-temporal mereotopology. Then, a mathematical description of product relationships based on mereotopology and temporal relationships is introduced. The long term aim is the representation of the outcomes in a formal ontology, in order to allow reuse and collaborative exploitation of the assembly knowledge in the different product lifecycle phases.Copyright