基于本体和粗糙集的协同产品设计知识约简

协同产品设计具有知识来源广、知识类型复杂多样等特点。为简化产品设计知识库并从中有效地提取出对产品设计人员有价值的知识,提出了基于本体和粗糙集的协同产品设计知识约简方法。首先通过引入本体技术对设计知识进行本体建模、显式定义语义和统一表达,以增加产品设计知识的语义;然后通过决策属性的正域及核求解等知识约简方法将设计知识库中对设计人员不重要的、冗余的知识进行约简,精练设计知识库,分析并求解出了约简后知识库中知识的依赖度,从而为设计人员选取与设计密切相关的知识提供依据。最后以汽车发动机的协同设计为例介绍了本文的方法。     

A framework for collaborative top-down assembly design

This paper presents a new system framework for collaborative top-down assembly design. Different from current computer-aided design (CAD) systems, the framework allows a group of designers to collaboratively conduct product design in a top-down manner. In our framework, a multi-level and distributed assembly model is adopted to effectively support collaborative top-down assembly design. Meanwhile, fine-granularity collaborative design functionalities are provided. First, the coupled structural parameters involved in the distributed skeleton models of the product can be collaboratively determined by the correlative designers based on fuzzy and utility theory. Second, agent based design variation propagation is achieved to ensure the consistency of the multi-level and distributed assembly model during the whole design process. Third, collaborative design of assembly interfaces between the components assigned to different designers is supported. The prototype implementation shows that our framework works well for supporting practical collaborative top-down assembly design.     

Creating shared design thinking process for collaborative design

Shared understanding about both the design content and the design process has significant meaning for collaborative design, which influences the quality of final products. Existing approaches have difficulties in supporting designers to structure and share their design thinking while they are performing practical tasks. In this paper we propose Shared Design Thinking Process Model (S-DTPM) to support collaborative design, which is based on co-evolutionary design theory and existing design rationale frameworks. Two principles for S-DTPM have been considered. The elements and representation schema of S-DTPM have been discussed in detail. Based on S-DTPM, a prototype system has been developed for supporting collaborative thinking and capturing shared design rationale. An example, collaborative design is taken to validate the proposed model. S-DTPM can help designers to create shared understanding about the design as well as record shared design thinking process for future use such as design review, design change and redesign.     

Integration of fuzzy logic, genetic algorithms and neural networks in collaborative parametric design

The solution to a design problem is extracted through the exploitation of the design knowledge in the context of a space of solution alternatives. The design process incorporates a series of decision making and knowledge management issues, which should be often addressed through collaboration among diverse stakeholders. The alternative solutions must usually be shaped under different formalisms and evaluated against commonly accepted objective criteria.The current paper presents an approach that integrates soft-computing techniques in order to facilitate the computer-aided collaboration among designers. CopDeSC (Collaborative parametric Design with Soft-Computing) is the name of the system developed in order to implement this approach whose key features are: (a) the collaborative structuring of design parameter hierarchies, (b) the modeling of the design objectives through fuzzy preferences stated by the designers on certain design parameters, (c) the deployment of genetic algorithms for locating the optimum solution and (d) the utilization of records of elite solutions that are submitted in a neuro-fuzzy approximation in order to produce a simplified problem formulation, suitable for addressing redesign tasks in significantly less computational time.The efficiency of CopDeSC is evaluated in an example case of the parametric design of oscillating conveyor that has been conducted by a group of designers.     

An assembly oriented design framework for product structure engineering and assembly sequence planning

The paper describes a novel framework for an assembly-oriented design (AOD) approach as a new functional product lifecycle management (PLM) strategy, by considering product design and assembly sequence planning phases concurrently. Integration issues of product life cycle into the product development process have received much attention over the last two decades, especially at the detailed design stage. The main objective of the research is to define assembly sequence into preliminary design stages by introducing and applying assembly process knowledge in order to provide an assembly context knowledge to support life-oriented product development process, particularly for product structuring. The proposed framework highlights a novel algorithm based on a mathematical model integrating boundary conditions related to DFA rules, engineering decisions for assembly sequence and the product structure definition. This framework has been implemented in a new system called PEGASUS considered as an AOD module for a PLM system. A case study of applying the framework to a catalytic-converter and diesel particulate filter sub-system, belonging to an exhaust system from an industrial automotive supplier, is introduced to illustrate the efficiency of the proposed AOD methodology.     

Development of control mechanisms to support coherency of product model during cooperative design process

Product development became an increasingly collaborative and distributed activity. Collaborative design process gathers experts from different backgrounds and areas for a common objective about product development. An effective exchange support is expected to share and integrate design knowledge avoiding conflicts between designers. The management of heterogeneous product representation is a major step to integrate expert activities. To successfully manage this process, this paper proposes: (1) A research experimental platform for cooperative design in product development processes. (2) A new constraint based model to maintain complex relationships in multi-disciplinary cooperative design. (3) A model differentiation technique, which identifies differences and conflicts between models. (4) A Meta-rule concept, which controls the constraint network in design process, leading to a new notification mechanism to present conflict to all corresponding actors.     

Ontology design with a granular approach

Ontology design for complex applications is quite a challenge. The quality of an ontology is highly dependent upon the capabilities of designers, and the collaborative design process is hampered by the difficulty of balancing the viewpoints of different designers. In this paper, we present a granular view of ontology: ontologies are granular, ontologies are granular approximations of conceptualizations and conceptual-relation granules of an ontology are ordered tuples. We then propose a corresponding granular ontology design approach. In our granular ontology design approach, the unified granular cognition level and hierarchies of sub-concepts are initialized before ontological terms are designed in detail, which reduces the subjective effects of the capabilities of designers. Our approach also introduces the idea of optimization to choose an optimal subset, which can best approximate the real concept domain, from the knowledge rule set presented by different domain experts. The optimal subset is chosen on the basis of the principle of granular ontology knowledge structure.     

A user requirement driven framework for collaborative design knowledge management

In today’s competitive global marketplace and knowledge-based economy, user requirement becomes an important input information for enterprises to develop new product and a critical factor to drive product collaborative design evolution. Meanwhile, there remains no consensus on how best to support knowledge activities and significant challenges to establishing design information management facing to rapid collaborative product development with dynamic user requirement. This paper introduces solutions for designer to deal with dynamic user requirement information through requirement evaluation and prediction method. In this study, we propose a user requirements-oriented knowledge management concept that is based on a four level hierarchy map model with special regard to knowledge collaboration and information communication. Furthermore, a novel distributed concurrent and interactive user requirement database was constructed, and the framework driven by user requirement was put forward to support collaborative design knowledge management. Finally, the service robot design project of a start-up company is used as a case study to explain the implementation of proposed framework.     

Development of a distributed collaborative design framework within peer-to-peer environment

Distributed collaborative design and manufacture enables manufacturing organizations to maintain competitiveness in the fiercely competitive global industry. This requires that the distributed system not only maintains data consistency across globally-distributed locations seamlessly, but also allows team members to access the storage system and computing resources transparently and securely. Current grid applications mainly based on client-server architecture are inflexible and rigid for fast changing collaborations among manufacturers, especially for small and medium enterprises. In this paper, a distributed collaborative design framework is presented with a hybrid of grid and peer-to-peer technology. In order to access computational resources for design, analysis and process simulation, a meta-scheduler is designed and implemented. It helps in resource discovery and optimal utilization of resources. A test bed is established, based on the framework proposed to demonstrate a distributed collaborative design and manufacturing environment.     

Category theory-based collaborative design methodology for mechatronic systems

Recent advances in companies are characterized by highly dynamic, knowledge-intensive and collaborative process. This has become primary concern for mechatronic systems since they involve multiple disciplines and knowledge. This requires a close exchange in order to share knowledge between the different design teams. The first step in knowledge sharing is to identify the most important knowledge that need to be capitalized, which we call “crucial knowledge”. During this exchange, heterogeneous knowledge and modelling languages are involved in the design process, which can lead to conflicts. Hence, the challenge is to continuously capture and handle such conflicts between expert models. Thus, the focus of this paper is to propose a new collaborative design model suitable for mechatronic concurrent design. Our contribution lies in identifying crucial knowledge and resolving conflicts in a formal way in order to ensure efficient collaboration. Our methodology called Category Theory-based Collaborative Design (CaTCoD) is described with its associated meta-model. A demonstrator is also used to validate the proposed methodology using an example from the aeronautic field.     

An Exploratory Study: Supporting Collaborative Multimedia Systems Design

Multimedia systems design generally requires a collaborative effort from a group of designers with a variety of backgrounds and tasks, such as content experts, instructional designers, media specialists, users, and so forth. However, currently available design tools on the market are mainly designed for a single user. Tools intended to support a collaborative design process should coordinate independent activities of individual designers.This research investigated support for work groups engaged in designing multimedia systems. Specifically, it discussed a new collaborative design environment, called the KMS (Knowledge Management System)-based design environment, in which multimedia designers could share their design knowledge freely. Through two experimental groups, the research investigated impacts of the KMS-based design environment on their collaborative design activities (knowledge creating, knowledge securing, knowledge distributing, and knowledge retrieving activities). The research findings showed that the KMS-based design environment was a promising environment for collaborative multimedia systems design. More specifically, the research findings indicated that the KMS-based design environment supported creating, securing, and retrieving knowledge, but it did not support distributing knowledge. In addition, the research found that the social interactions between group members played important roles in the success of the collaborative multimedia systems design and that the KMS-based design environment did not support the socialization of group members. Furthermore, the research found that the inability of the KMS-based design environment to support the socialization was linked to its low performance level in supporting the knowledge distributing activity. The research explored the desired features of a collaborative support tool for multimedia systems design.     

Collaborative intelligent CAD framework incorporating design history tracking algorithm

This paper shows a new and efficient collaborative intelligent Computer Aided Design (CAD) framework in a theoretical study. While other collaborative CAD frameworks or protocols focus on decreasing the waiting time for updating design or communication methods for design review among collaborative designers, the suggested collaborative design protocol determines the next design ownership criterion with the objective of minimizing redundant design stages and design bottlenecks using the design history. In addition, the suggested framework generates an efficient reverse-engineered process for achieving the final design target with identification of redundant designs and how these can be prevented while resolving other existing collaborative design issues. As a design history mechanism, a feature-based design history tracking algorithm is suggested. In each design stage, the modeling activities are mapped to the related geometry and topology information. This information is reasoned into features using the feature design history graph (FDHG) and modified attribute adjacency graph (MAAG). The identified features are utilized for determining the redundant design stage and how it can be changed efficiently using the tracking algorithm. As the size of the design history increases with the number of collaborative designers and their design stages, this design history mechanism contributes to a decrease in size and captures the characteristics of design using features. As possible directions for future research this suggested framework can provide an insight into the design tendencies of designers and also be used as a reference model for intelligent CAD systems with an extracted design history-based knowledge database.     

A knowledge intensive multi-agent framework for cooperative/collaborative design modeling and decision support of assemblies

Multi-agent modeling has emerged as a promising discipline for dealing with decision making process in distributed information system applications. One of such applications is the modeling of distributed design or manufacturing processes which can link up various designs or manufacturing processes to form a virtual consortium on a global basis. This paper proposes a novel knowledge intensive multi-agent cooperative/collaborative framework for concurrent intelligent design and assembly planning, which integrates product design, design for assembly, assembly planning, assembly system design, and assembly simulation subjected to econo-technical evaluations. An AI protocol based method is proposed to facilitate the integration of intelligent agents for assembly design, planning, evaluation and simulation process. A unified class of knowledge intensive Petri nets is defined using the O-O knowledge-based Petri net approach and used as an AI protocol for handling both the integration and the negotiation problems among multi-agents. The detailed cooperative/collaborative mechanism and algorithms are given based on the knowledge objects cooperation formalisms. As such, the assembly-oriented design system can easily be implemented under the multi-agent-based knowledge-intensive Petri net framework with concurrent integration of multiple cooperative knowledge sources and software. Thus, product design and assembly planning can be carried out simultaneously and intelligently in an entirely computer-aided concurrent design and assembly planning system.     

Internet Based Collaborative Product Conceptual Design

Generation of Product Concept needs to give full play to the designers' innovative potential and collaborative work of experts in different fields. However, the collaborative innovative capabilities of geographically distributed designers are often limited and hindered by space and time. Therefore, on the basis of the requirements analysis of Internet based collaborative conceptual design and the research work we have done, this paper proposes the overall framework of supporting collaborative conceptual design on Internet. Based on this overall framework, the authors further put forward collaborative conceptual design process model that includes three stages: concept generation, concept communication and optimal product concept selection. At the end of the paper, the experiment environment of collaborative design is described. The overall framework and collaborative conceptual design process model proposed can take full advantage of Internet and give full play to experts' experiences and wisdom, so that the rapid development and innovative design of product can be provided with effectively and efficiently implemental mode and support on Internet.     

Internet-enabled real-time collaborative assembly modeling via an e-Assembly system: status and promise

Collaborative CAD systems enabling collaboration in computer-aided design processes among distributed designers are gaining more and more attention. Yet, such systems, especially in support of collaborative assembly modeling, are hardly achievable. Targeting this gap, this paper addresses an Internet-enabled real-time collaborative assembly modeling system, named e-Assembly. This emerging system allows a group of geographically dispersed designers to jointly build an assembly model in real time over the Internet. In particular, this paper proposes a new assembly representation, called Collaborative Assembly Representation, for Internet-based collaborative assembly modeling. Also, collaborative assembly constraint satisfaction is addressed based on three coordination rules embedded in e-Assembly. Furthermore, the system architecture and realization of e-Assembly are provided. Finally, a prototypic implementation of e-Assembly is presented for demonstration and discussion.     

A spatiotemporal information management framework for product design and assembly process planning reconciliation

This paper introduces an innovative framework for product design and assembly process planning reconciliation. Nowadays, both product lifecycle phases are quasi concurrently performed in industry and this configuration has led to competitive gains in efficiency and flexibility by improving designers’ awareness and product quality. Despite these efforts, some limitations/barriers are still encountered regarding the lack of dynamical representation, information consistency and information flow continuity. It is due to the inherent nature of the information created and managed in both phases and the lack of interoperability between the related information systems. Product design and assembly process planning phases actually generate heterogeneous information, since the first one describes all information related to “what to be delivered” and the latter rationalises all information with regards to “how to be assembled”. In other words, the integration of assembly planning issue in product design requires reconciliation means with appropriate relationships of the architectural product definition in space with its assembly sequence in terms of time. Therefore, the main objective is to provide a spatiotemporal information management framework based on a strong semantic and logical foundation in product lifecycle management (PLM) systems, increasing therefore actors’ awareness, flexibility and efficiency with a better abstraction of the physical reality and appropriate information management procedures. A case study is presented to illustrate the relevance of the proposed framework and its hub-based implementation within PLM systems.     

Negotiation within a multi-agent system for the collaborative design of light industrial buildings

This paper is a review of intelligent agents with respect to their use within the Agent-Based Support for The Collaborative Design of Light Industrial Buildings (ADLIB) project. In the ADLIB project, the core objective is to develop a multi-agent system (MAS) framework for the representation of activities and processes involved in collaborative design of light industrial buildings. This includes the planning and fabrication of steel structural components. ADLIB intelligent agents are concerned with modelling action and knowledge in a collaborative environment. The design process that ADLIB's agents are trying to automate is the interaction and negotiation between specialist design team members. Each team member with a different area of expertise will be primarily concerned with his own area of interest. This paper starts with an introduction to intelligent agents. It then moves on to a discussion of agent classification systems and negotiation theories and their applications in MAS. The last section analyses the needs of agents within the ADLIB project. A negotiation protocol and strategy are then presented.     

Multidisciplinary interface model for design of mechatronic systems

The design of mechatronic systems is based on the integration of several disciplines, such as mechanical, electrical and software engineering. How to achieve an integrated multidisciplinary design during the development process of mechatronic systems has attracted the attention of both academia and industry. However, solutions which can fully solve this problem have not been proposed by now. The concept of multidisciplinary interface represents the logical or physical relationship integrating the components of the mechatronic system or the components with their environment. As the design of mechatronic systems is a multidisciplinary work, the multidisciplinary interface model can be considered as one of the most effective supports to aid designers for achieving the integrated multidisciplinary design during the development process. The paper presents a multidisciplinary interface model for design of mechatronic systems in order to enable the multidisciplinary integration among design team members from different disciplines. On the one hand, the proposed model ensures the consistency of interface defined by the designers. On the other hand, it helps the designers to guarantee the different components integrate correctly. The interface model including three concepts: classification, data model and compatibility rules. The multidisciplinary interface model is implemented by a case study based on a 3D measurement system.     

基于知识的试油方案协同设计方法应用研究

为解决试油三项设计系统在实际应用中因认知水平、知识水平和实际需求不同导致的设计方案差异大、标准不统一的问题,如何以一种形式化、标准化的方式来表示试油方案设计领域知识,实现方案标准统一化,提高试油方案协同设计系统的智能性是面临的一个重要问题。在研究试油方案协同设计工作流的基础上引进知识的概念,将试油领域本体与试油方案协同设计的具体应用需求相结合提出了一种基于知识的试油方案协同设计方法。该方法介绍了试油领域本体构建、应用以及协同工作流构建等技术和方法,利用统一的知识表示,使知识与试油方案协同设计业务流程紧密关联,很好地解决了实际应用中方案标准统一化以及知识重用性的问题。目前系统在使用中,提高了方案设计的准确性和设计效率。