Real-time collaborative design based on operation semantics in distributed CAD environment

This paper proposes a collaborative design model based on operation semantics in a distributed computer-aided design (CAD) environment. The goal is to reduce time consumption in data format conversion and the requirement of network bandwidth so as to improve the cooperative ability and the synchronization efficiency. Firstly, real-time collaborative design is reviewed and three kinds of real-time collaborative design models are discussed. Secondly, the concept of operation semantics is defined and the framework of an operation semantics model is presented. The operation semantics carries the original design data and actual operation process to express design intent and operation activity in conventional CAD systems. Finally, according to the operation semantics model, a CAD operation primitive is defined which can be retrieved from and mapped to the local CAD system operation commands; a distributed CAD collaborative architecture based on the model is presented, and an example is given to verify the model.

A Task-oriented Modular and Agent-based Collaborative Design Mechanism for Distributed Product Development

The rapid expansion of enterprises makes product collaborative design （PCD） a critical issue under the distributed heterogeneous environment, but as the collaborative task of large-scale network becomes more complicated, neither unified task decomposition and allocation methodology nor Agent-based network management platform can satisfy the increasing demands. In this paper, to meet requirements of PCD for distributed product development, a collaborative design mechanism based on the thought of modularity and the Agent technology is presented. First, the top-down 4-tier process model based on task-oriented modular and Agent is constructed for PCD after analyzing the mapping relationships between requirements and functions in the collaborative design. Second, on basis of sub-task decomposition for PCD based on a mixed method, the mathematic model of task-oriented modular based on multi-objective optimization is established to maximize the module cohesion degree and minimize the module coupling degree, while considering the module executable degree as a restriction. The mathematic model is optimized and simulated by the modified PSO, and the decomposed modules are obtained. Finally, the Agent structure model for collaborative design is put forward, and the optimism matching Agents are selected by using similarity algorithm to implement different task-modules by the integrated reasoning and decision-making mechanism with the behavioral model of collaborative design Agents. With the results of experimental studies for automobile collaborative design, the feasibility and efficiency of this methodology of task-oriented modular and Agent-based collaborative design in the distributed heterogeneous environment are verified. On this basis, an integrative automobile collaborative R＆D platform is developed. This research provides an effective platform for automobile manufacturing enterprises to achieve PCD, and helps to promote product numeralization collaborative R＆D and management development.

MULTI-AGENT COLLABORATIVE DESIGN SYSTEM MODEL BASED ON THE INTERNET AND EXPERIMENTS

Development of complicated products is a project of system engineering It involves extensive and complicated knowledge,design methods and auxiliary technology Various factors affect each other So,modern product development is a typical group problem with distributed and dynamic features It is apparent superiority to solve this problem with a multi agent system representing various knowledge domains Distributed artificial intelligence knowledge being used,the multi agent collaborative design system concept and model based on Internet environment are put forward The realizing method of product developing agents,interactive process among multi agents,and organization and implementing of the design project of the multi agent collaborative design system are discussed in detail Application examples are also presented.

Maturity assessment model for aircraft collaborative design software solution

In order to assure quality and control process in the development of the aircraft collaborative design software, a maturity assessment model is proposed. The requirements designing—house of quality is designed to evaluate the maturity degree of the solution, and the evaluation results can help to manage and control the development process. Furthermore, a fuzzy evaluation method based on the minimum deviation is proposed to deal with the fuzzy information. The quantitative evaluation result of the maturity degree can be calculated by optimizing the semantic discount factor aim for the minimum deviation. Finally, this model is illustrated and analyzed by an example study of the aircraft collaborative design software.

COLLABORATIVE DESIGN OF MULTIPHYSICS PROBLEMS

Collaborative design is recommended to solve multiphysics problems （MPPS）. Firstly, mathematical model of MPPS is constructed and solved by a proposed partitioned method, analysis of which suggests that collaborative design be feasible to solve MPPS. As the key technology of col-laborative design of MPPS, a task collaboration algorithm is then proposed. To develop the applica-tion framework of collaborative design, applied unified process（AUP） is proposed based on rational unified process（RUP）. Then AUP is used to develop the collaborative design platform, whose function framework is constructed according to the process of project management. Finally three MPPS are solved on this platform and the results suggest that the proposed model, algorithm and framework be feasible.

Collaborative Design in PDM / 3D CAD Integrated Environment

Some key issues in supporting collaborative design in product data management（PDM ） system and 3D computer aided design（CAD） system integrated environment are analyzed. The general architecture of the integrated environment is divided into five tiers and employs the transparently integrated mode, with the mode, function calling and information exchanging among independent PDM and CAD processes are carried out via message translation /parse approach. Product layout feature（PLF ） model definition is presented, PLF model is used to represent design intention at the preliminary design phase. The collaborative design methodology employing the PLF model in PDM/3D CAD integrated environment is analyzed. The design methodology can speed up the design process, reduce the investment and improve the product quality.

XML-based Data Processing in Network Supported Collaborative Design

In the course of network supported collaborative design, the data processing plays a very vital role. Much effort has been spent in this area, and many kinds of approaches have been proposed. Based on the correlative materials, this paper presents extensible markup language （XML） based strategy for several important problems of data processing in network supported collaborative design, such as the representation of standard for the exchange of product model data （STEP） with XML in the product information expression and the management of XML documents using relational database. The paper gives a detailed exposition on how to clarify the mapping between XML structure and the relationship database structure and how XML-QL queries can be translated into structured query language （SQL） queries. Finally, the structure of data processing system based on XML is presented.

Research on message resource optimization in computer supported collaborative design

An adaptive mechanism is presented to reduce bandwidth usage and to optimize the use of computing resources of heterogeneous computer mixes utilized in CSCD to reach the goal of collaborative design in distributed-synchronous mode. The mechanism is realized on a C/S architecture based on operation information sharing. Firstly, messages are aggregated into packets on the client. Secondly, an outgoing-message weight priority queue with traffic adjusting technique is cached on the server. Thirdly, an incoming-message queue is cached on the client. At last, the results of implementing the proposed scheme in a simple collaborative design environment are presented.

Evaluation and selection of the ship collaborative design resources based on AHP and genetic and simulated annealing algorithm

The characteristics of the design resources in the ship collaborative design is described and the hierarchical model for the evaluation of the design resources is established. The comprehensive evaluation of the co-designers for the collaborative design resources has been done from different aspects using Analytic Hierarchy Process （AHP） ,and according to the evaluation results,the candidates are determined. Meanwhile,based on the principle of minimum cost,and starting from the relations between the design tasks and the corresponding co-designers,the optimizing selection model of the collaborators is established and one novel genetic combined with simulated annealing algorithm is proposed to realize the optimization. It overcomes the defects of the genetic algorithm which may lead to the premature convergenee and local optimization if used individually. Through the application of this method in the ship collaborative design system,it proves the feasibility and provides a quantitative method for the optimizing selection of the design resources.

Variable Relation Parametric Model on Graphics Modelon for Collaboration Design

A new approach to variable relation parametric model for collaboration design based on the graphic modelon has been put forward. The paper gives a parametric description model of graphic modelon, and relating method for different graphic modelon based on variable constraint. At the same time, with the aim of engineering application in the collaboration design, the autonmous constraint in modelon and relative constraint between two modelons are given. Finally, with the tool of variable and relation dbase, the solving method of variable relating and variable-driven among different graphic modelon in a part, and double-acting variable relating parametric method among different parts for collaboration are given.

Agent-based Collaborative Design Framework Supporting Synchronization and Asynchronization on Internet

On the basis of analysis of the research issues and requirement of collaborative design, we propose the overall framework of agent based collaborative design on Internet. Then, we describe the implementation of synchronous and asynchronous collaborative design process based on standardized design activities under the overall framework. In order to realize design message passing, the DMP Protocol is proposed as well in this paper and described in detail.

PERFORMANCE-BASED INTELLIGENT RESOURCE DESCRIPTION MODEL FOR INTERNET-BASED PRODUCT DESIGN

Issues on intelligent resource description and multiple intelligent resources integration for lntemet based collaborative design are analyzed. A performance-based intelligent resource description model for lnternet-based product design is proposed, which can help to create, store, manipulate and exchange intelligent resource description information for applications, tools and systems in Interact-based product design. A method to integrate multiple intelligent resources to fulfill a complex product design and analysis via lntemet is also proposed. A real project for improving the bearing system design of a turbo-expander with many intelligent resources in prominent universities is presented as a case study.

Research on Product Digital Collaborative Design System

Network economy had changed manufacturing environme nt at all. Open global market offer more choice to customer, and it become changea ble and unpredictable as consumers’ needs become more and more characteristic an d diversified. Various new technology coming forth and application accelerate th e rapid change of the market. The manufacturing enterprises were compelled t o change their strategy by the variability of the market, and time has been put to the all-important place. There is a need driven by the market to set up a ne twork design and manufacturing mode which have rapid market responsiveness. In order to meet the need for network manufacturing, the organization and manage ment of manufacturing enterprise need a completely innovation, next generation o f manufacturing system must have the character such as digitization, flexibility , agility, customization and globalization and so on. As for an enterprise in au to industry, how to gather together the orders through the distribution, and rap id produce the product which can meet the customer’s need, it is the key that th e contemporary enterprises succeed in the competitive market. The competitive market requires rapid product development. Close cooperation amo ng the designers will accelerate the product development by shortening the devel opment cycle, improving the product quality and reducing the investment. It has been emphasized in the methodology of concurrent engineering (CE). But sometimes those partners are distributed in the world, so there is a need for an importan t technology contribution to collaborative engineering, and supporting distribut ed designers for rapid product development. This paper focuses on a collaborative design system: Product Digit Collaborative Design System (PDCDS). The solution of PDCDS can make it more efficient and rel iable to visit teledata as well as we can get it from local database. It will be ease to get the newest design process information aided by PDCDS, and it will h ave higher efficiency by collaborative work. Comparing with other traditional Pr oduct Data Management (PDM) software system, PDCDS have some new characters such as group, dynamicness, synchronization or asynchronism working mode, and the hi story recorder is needed, and it also surport Webservice.

Conflict Resolution Based on Collaborative Design of Grid Services

To the issues of low efficiency of conflict resolution method in collaborative design, we proposed a method, which is conflict resolution about collaborative design based on grid services.It uses the grid services from the current design points, uses the method of retrospective thinking to find the conflict point by detecting, and then uses the corresponding method to resolve the conflict point according to the conflict characteristic, after that carried on the conflict detection again. If there is still the conflict, resolve the conflict point again, until the conflict no longer exists. This method combines various traditional resolution methods, makes full use of the grid idle high-performance large-scale sharing resources. With this method the collaborative design conflict resolution cost reduced and the conflict resolution efficiency was raised. And then the problem which is not handled completely was then solved, so that the conflict resolution Quality was guaranteed.

An Approach to Collaborative Design Based on Distributed Constraint-Net

We focuse on design process in concurrent engineering and propose an, approach to collaborative design based on distributed constraint-net. The approach adopts agent technology to express kinds of distributed constraints. And through the cooperation among agents, the consistency of constraint is maintained and the constraint conflict is detected and eliminated. The constraints are satisfied concurrently and distributively. Based on the proposed approach, the collaborative design process in concurrent engineering can be well supported.

Study of the ship design process model for collaborative design

The ship design process model is the basis for developing the ship collaborative design system under network environment.According to the characteristics of the ship design, a method for dividing the ship design process into three layers is pat forward, that is project layer, design task layer and design activity layer, then the formalized definitions of the ship design process model, the decomposing principles of the ship design process and the architecture of the ship collaborative design (SDPM) system are presented. This method simplifies the activity network, makes the optimization and adjustment of the design plan convenient and also makes the design process easier to control and change, at last the architecture of the ship collaborative design system is discussed.

Research on Key Techniques of Collaborative Design System

The development of product is a complex process. Collaboration is necessary to this process to support multi-function teams’ participation in this process at the same time. Effective task decomposition is the prerequisite of collaborative design and constraint network was used to express the relationship among design participants. In order to make the coupling collaborative design go smoothly, a constraint satisfaction model based on dynamic constraint is put forward. An integrated-based conflict resolution model is advanced to resolve the complex conflict during the process of collaborative design.

Conflict detection in collaborative architectural pipe routing design based on constraint network

This paper analyzes conflict features in architecture pipe routing,and builds a pipe routing design conflict model by taking into account of discrete nominal internal diameter selection of pipes,material costs,and conflict solution sequence.Considering pipe routing as an assembling process,a conflict detection approach for pipe routing in collaborative architectural design is proposed based on an aforementioned model.Constraint network is used to describe the relationship among pipe routing design parameters and constraints;design conflicts are detected by matching designers' input and constraint network;and detected design conflicts are reordered according to the number of pipe parameters in conflicts.In order to support the collaborative requirement of pipe routing design,a prototype system using browser/server architecture is developed.An illustrative example of water pipe routing in a room is used to show the effectiveness and efficiency of the approach.

Collaborative Design of Parametric Sustainable Architecture

Sustainable architecture is complex. Many aspects, differently important to many stakeholders, are to be optimized. BIM should be used for this. Building Information Modellingis a collaborative process where all stakeholders integrate and optimize their information in a digital 3D model. Sometimes it is called Green BIM. But what exactly is that？ Is the International Standard Organization IFC standard useful for this？ And is it compatible with new developments in parametric design？ Advantages and disadvantages of BIM are listed. Full parametric design is needed because it keeps the design flexible and open for changes until the end of the design process. However it is not compatible with IFC; only object parametric design is. A possible way out of this paradox could be the use of scripts that only create objects if they are not already in the BIM database and otherwise only adapt their properties. An example of parametric sustainable architectural design explains the mentioned issues.

A Notation to Support Exploring Collaboration in Design Teams

Collaboration in large projects is a major challenge for contemporary architectural practice and this paper presents a notation for describing and analyzing how these collaborations can take place.Based on an extensive literature review some opportunities were found for the development of a notation that combined three particular aspects:network diagrams,Euler diagrams and a model from architectural design.An exploratory case study was conducted based on the collaboration during a complex architectural project,which combined three approaches:document analysis,semi-structured interviews with key stakeholders and a comparison of the documents with results from the interviews.The notation demonstrated to be suitable for two purposes:to improve the understanding of particular design events and as support material for presenting and exploring collaborations.Results indicate that the notation was suitable,comprehensible and flexible,and it demonstrated good value when used in speculative ways,such as an intermediary design artifact that supports discussion and improvements in the collaboration process,which indicates promising future directions.It can also be argued that,similar to a sketch,the notation can also support the process of planning and“designing”the interaction between teams in design fields and even in other project-based organizations.