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.     

RUN TO RUN CONTROL OF TIME-PRESSURE DISPENSING SYSTEM

In electronics packaging the time-pressure dispensing system is widely used to squeeze theadhesive fluid in a syringe onto boards or substrates with the pressurized air. However complexity ofthe process, Which includes the air-fluid coupling and the nonlinear uncertaintes, makes it difficult tohave a consistent process performance. An integrated dispensing process model is first introduced andthen its input-output regression relationship is used to design a run to run control methodology for thisprocess. The controller takes EWMA scheme and its stability region is given. Experimental resultsverify the effectiveness of the proposed run to run control method for dispensing process.     

DESIGN METHOD OF MAGNETO- RHEOLOGICAL FLUID SHOCK ABSORBER FOR CAR SUSPENSION

The Bingham constitutive model, which is previously used in depiction of magnetorheological （MR） fluids rheological behaviors for design devices, exhibits discontinuous characteristics in representation of pre-yield behaviors and post-yield behaviors. A Biviscous constitutive model is presented to depict rheological behaviors of MR fluids and design automotive shock absorber. Quasi-static flow equations of MR fluids in annular channels are set theoretically up based on Navier-Stokes equations and several rational simplifications are made. And both flow boundary conditions and flow compatibilities conditions are established. Meantime, analytical velocity profiles of MR fluids though annular channels are obtained via solution of the quasi-static flow equations using Biviscous constitutive model. The prediction methodology of damping force offered by MR fluid shock absorber is formulated and damping performances are predicated in order to determine design parameters. MR fluid shock absorber for Mazda 323 car suspension is designed and fabricated in Chongqing University, China. Measurements from sinusoidal displacement cycle by Shanchuan Shock Absorber Ltd. of China North Industry Corporation reveal that the analytical methodology and design theory are reasonable.     

OPTIMIZATION DESIGN OF HYDRAULIC MANIFOLD BLOCKS BASED ON HUMAN-COMPUTER COOPERATIVE GENETIC ALGORITHM

Optimization design of hydraulic manifold blocks (HMB) is studied as a complex solid spatial layout problem. Based on comprehensive research into structure features and design rules of HMB, an optimal mathematical model for this problem is presented. Using human-computer cooperative genetic algorithm (GA) and its hybrid optimization strategies, integrated layout and connection design schemes of HMB can be automatically optimized. An example is given to testify it.     

MODELING AND IMPLEMENTATION OF A DISTRIBUTED SHOP FLOOR MANAGEMENT AND CONTROL SYSTEM

Adopting distributed control architecture is the important development direction for shop floor management and control system, is also the requirement of making it agile, intelligent and concurrent. Some key problems in achieving distributed control architecture are researched. An activity model of shop floor is presented as the requirement definition of the prototype system. The multi-agent based software architecture is constructed. How the core part in shop floor management and control system, production plan and scheduling is achieved. The cooperation of different agents is illustrated. Finally, the implementation of the prototype system is narrated.     

Design Change Model for Effective Scheduling Change Propagation Paths

Changes in requirements may result in the increasing of product development project cost and lead time,therefore,it is important to understand how requirement changes propagate in the design of complex product systems and be able to select best options to guide design.Currently,a most approach for design change is lack of take the multi-disciplinary coupling relationships and the number of parameters into account integrally.A new design change model is presented to systematically analyze and search change propagation paths.Firstly,a PDS-Behavior-Structure-based design change model is established to describe requirement changes causing the design change propagation in behavior and structure domains.Secondly,a multi-disciplinary oriented behavior matrix is utilized to support change propagation analysis of complex product systems,and the interaction relationships of the matrix elements are used to obtain an initial set of change paths.Finally,a rough set-based propagation space reducing tool is developed to assist in narrowing change propagation paths by computing the importance of the design change parameters.The proposed new design change model and its associated tools have been demonstrated by the scheduling change propagation paths of high speed train’s bogie to show its feasibility and effectiveness.This model is not only supportive to response quickly to diversified market requirements,but also helpful to satisfy customer requirements and reduce product development lead time.The proposed new design change model can be applied in a wide range of engineering systems design with improved efficiency.     

INTEGRATED LAYOUT DESIGN OF CELLS AND FLOW PATHS

The integrated layout problem in manufacturing systems is investigated. An integrated model for concurrent layout design of cells and flow paths is formulated. A hybrid approach combined an enhanced branch-and-bound algorithm with a simulated annealing scheme is proposed to solve this problem. The integrated layout method is applied to re-layout the gear pump shop of a medium-size manufacturer of hydraulic pieces. Results show that the proposed layout method can concurrently provide good solutions of the cell layouts and the flow path layouts.     

CASE-BASED PRODUCT CONFIGURATION AND REUSE IN MASS CUSTOMIZATION

The increasing complexity and size of configuration knowledge bases requres the provisionof advanced methods supporting the development of the actual configuration process and design reuse.A new framework to find a feasible and practical product configuration method is presented in masscustomization. The basic idea of the appoach is to integrate case-based reasoning (CBR) with a con-straint satisfaction problem(CSP). The similarity measure between a crisp and range is also given,which is common in case retrieves. Based on the configuration model, a product platform and customerneeds, case adaptation is carried out with the repair-based algorithm. Lastly, the methodology in theelevator configuration design domain is tested.     

Carbody structural lightweighting based on implicit parameterized model

Most of recent research on carbody lightweighting has focused on substitute material and new processing technologies rather than structures. However, new materials and processing techniques inevitably lead to higher costs. Also, material substitution and processing lightweighting have to be realized through body structural profiles and locations. In the huge conventional workload of lightweight optimization, model modifications involve heavy manual work, and it always leads to a large number of iteration calculations. As a new technique in carbody lightweighting, the implicit parameterization is used to optimize the carbody structure to improve the materials utilization rate in this paper. The implicit parameterized structural modeling enables the use of automatic modification and rapid multidisciplinary design optimization （MDO） in carbody structure, which is impossible in the traditional structure finite element method （FEM） without parameterization. The structural SFE parameterized model is built in accordance with the car structural FE model in concept development stage, and it is validated by some structural performance data. The validated SFE structural parameterized model can be used to generate rapidly and automatically FE model and evaluate different design variables group in the integrated MDO loop. The lightweighting result of body-in-white （BIW） after the optimization rounds reveals that the implicit parameterized model makes automatic MDO feasible and can significantly improve the computational efficiency of carbody structural lightweighting. This paper proposes the integrated method of implicit parameterized model and MDO, which has the obvious practical advantage and industrial significance in the carbody structural lightweighting design.     

ADAPTABLE DESIGN IN PRODUCT DEVELOPMENT

A newly emerging design pattern, named as adaptable design (AD), which aims at developing products that are adaptable from design to post-life cycle, is discussed. AD consists of four main phases: product modeling, design platform, specific design and product redesign. A new process-based design data model (PDDM) is presented which is organized according to the principles of convenient knowledge extraction, data representation, layout, sharing and reuse. Based on the PDDM, a universal design platform for product family development is established, which has characters of modularity, parameter-driven, variant design, etc. The framework of the platform is also proposed as a conceptual structure and overall logical organization for generating a family of products. AD methodology is successfully applied to develop a family of tunnel boring machine (TBM) for different engineering projects, with the efficiency of our developing team being greatly increased.     

CAPP与车间作业计划集成的研究

阐述在制造过程中ＣＡＰＰ与车间作业计划之间集成的必要性，分析目前ＣＡＰＰ与车间作业计划集成的方法：在分析式集成方法的基础上，提出分层规划集成的模型，并讨论此模型的系统结构和特点。     

基于PDM协同设计任务建模与调度方法研究

从产品数据管理系统中协同设计过程任务建模的角度出发,提出基于产品结构分解的协同设计过程人员-任务分配模型,建立任务结构的约束映射和基于可扩展着色Petri网的任务过程建模方法,实现Multi-agent协同设计过程任务调度集成框架,最后进行了系统实现.     

CAPP与调度集成多代理系统的资源冲突消解

针对CAPP与调度集成系统，研究了多代理混合系统的冲突消解结构和策略。首先建立了CAPP与调度集成的多代理模型，包括合作代理和非合作代理；提出了多代理系统的冲突消解决策逻辑；按照预消解、消解、协商和仲裁的阶段协调策略，提出了一个任务资源匹配过程和多个任务资源匹配过程中的资源冲突消解策略和相应的协商协议；开发了CSIMAS系统，以验证冲突消解策略和协商协议；分别讨论了工艺规划代理和车间代理冲突消解过程作为合作代理和非合作代理的实例。     

制造领域多智能体系统的技术研究

首先讨论了多智能体、计算机支持在协同共和和公共对象请求代理体系,综述了全能制造系统、供应链管理、虚拟企业、机器人、工艺规划、调度和装配等多智能体技术。在综合大量文献和已有研究的基础上,讨人了这些方向的主要研究方法、技术和现状,并指出基于多智能体的制造系统中的方法学研究、学习机制、集成化研究、合作机制和冲突消解等拟进一步研究的领域。     

集成制造环境下的计算机辅助工艺设计框架工具系统

在分析了ＣＡＰＰ研究和应用现状的基础上,设计了一种实用化的ＣＡＰＰ框架工具系统。该系统提供了检索式工艺设计、派生式工艺设计和创成式工艺设计三种工艺设计工具,并融三种工具于一种集成环境中,实现了ＣＡＰＰ的系统信息模型、功能模型及决策逻辑的柔性化和可重配置,较好地解决了ＣＡＰＰ系统的实用性、适用性和通用性问题。     

Computer aided process planning system based on workflow technology and integrated bill of material tree

It is extremely important for procedure of process design and management of process data for product life cycle in Computer Aided Process Planning (CAPP) system, but there are many shortcomings with traditional CAPP system in these respects. To solve these questions, application of workflow technology in CAPP system based on web-integrated Bill of Material (BOM) tree is discussed, and a concept of integrated BOM tree was brought forward. Taking integrated BOM as the thread, CAPP systematic technological process is analyzed. The function, system architecture, and implementation mechanism of CAPP system based on Browser/Server and Customer/Server model are expatiated. Based on it, the key technologies of workflow management device were analyzed. Eventually, the implementation mechanism of integrated BOM tree was analyzed from viewpoints of material information encoding, organization node design of integrated BOM tree, transformation from Engineering BOM (EBOM) to Process BOM (PBOM), and the programming implementation technology. __________ Translated from Computer Integrated Manufacturing Systems, 2005, 11 (11) (in Chinese)     

计算机辅助装配工艺设计集成化系统

阐述了发展装配CAPP集成化系统的意义 ,提出了产品装配模型结构 ,讨论了装配CAPP集成化系统的原理、结构和主要技术 ,建立了DFA与装配CAD/CAPP的集成化系统框架。     

APPLICATION OF STEP IN CAD/CAPP INTEGRATION

ＡＰＰＬＩＣＡＴＩＯＮＯＦＳＴＥＰＩＮＣＡＤ／ＣＡＰＰＩＮＴＥＧＲＡＴＩＯＮＷｕＲｕｉｒｏｎｇＺｈａｎｇＨｅｍｉｎｇＴｈｅＮａｔｉｏｎａｌＣＩＭＳＥｎｇｉｎｅｅｒｉｎｇＲｅｓｅａｒｃｈＣｅｎｔｅｒ,ＱｉｎｇｈｕａＵｎｉｖｅｒｓｉｔｙＡｂｓｔｒａｃｔＡ...     

基于工作流和集成化物料清单树的CAPP系统

在计算机辅助工艺设计系统中,面向产品全生命周期工艺设计的流程化与工艺数据的管理尤其重要.为解决传统的计算机辅助工艺设计系统在这些方面存在的问题,探讨了工作流技术在基于Web集成化物料清单树的计算机辅助工艺设计系统中的应用,提出了集成化物料清单树的概念,以集成化物料清单为主线,分析了计算机辅助工艺设计系统工艺流程,阐述了基于浏览器/服务器和客户机/服务器模式的计算机辅助工艺设计系统的功能、体系结构及其实现机制,并在此基础上分析了工艺工作流管理器的关键技术.最后,从物料信息编码、集成化物料清单树的组织节点设计、设计物料清单向工艺物料清单的转化,以及程序实现技术等方面详细分析了集成化物料清单树的实现机制.     

On-line integration of a process planning module with production scheduling

An approach to the on-line integration of process planning and production scheduling is reported. Based on a geometric modeller, a geometric analyser and a knowledge base, the process planner generates alternative process plans and provides automatic tool selection and calculation of the appropriate machining parameters. Time and cost estimations are input to the decision-making module in the production scheduling system that produces optimal scheduling decisions as well as a complete record of the actual state of the factory resources. An information flow, designed as a relational data model, maintains the interaction between the process planning and the production scheduling systems and provides the dynamic feedback to the process planner. Specific geometry features of the blank, the finished part and the cutting tools, and geometry features-based rules are stored in the database of a developed CAPP system by using a separate CAD interface. The integrated production planning and production scheduling system and the CAPP system were validated with rotational parts machining.