机械类外文翻译

A web based manufacturing service system for rapid product development Hongbo Lana Yucheng Dinga Jun Honga Hailiang Huangb Bingheng Lua Abstract This paper proposes a novel integrated system of rapid product development based on rapid prototyping and develops anetworked manufacturing service system which offers better support for the rapid product development in small and mediumsized enterprises by taking full advantage of the quickly evolving computer network and information technologies The architecture of the networked manufacturing service system is presented Furthermore some of the key issues includingmodelling and planning a manufacturing chain selecting feasible collaborative manufacturers queuing a manufacturing task using the synchronously collaborative work environment and constructing a suitable running platform are described in detail Java enabled solution together with web techniques is employed for building such a networked service system Finally an actual example is provided illustrating the applicationof this service system Keywords Rapid product development Rapid prototyping Service system Web based application 1 Introduction This is the era of information technology Informationtechnology has influenced every realm of society and dramatically impacted on the traditional industry Current industries are facing the new challenges quick response to business opportunity has been consideredas one of the most important factors to ensurecompany competitiveness manufacturing industry isevolving toward digitalization network and globalization In order to respond to the change effectively manufacturing strategy has to be modified from timeto time in accordance with the market situation andcustomer demand Any change of strategy should enable manufacturers to be better equipped themselves with capabilities to cope with demands suchas a faster response to market changes a shortenedlead time of production improved quality and speed the ability to deliver quality products to global customers and improved communications and transportationsystem 1 It is an established fact that the useof computers in design and manufacturing constitutesthe most significant opportunity for substantial productivitygain in industry It has now been widelyaccepted that the future of manufacturing organizationswill be information oriented knowledge drivenand much of their daily operations will be automatedaround the global information network that connectseveryone together 2 In order to meet the demand ofrapid product development various new technologiessuch as reverse engineering RE rapid prototyping RP and rapid tooling RT have emerged and areregarded as enabling tools with abilities to shorten theproduct development and manufacturing time Forexample it has been claimed that RP can cut newproduct development costs by up to 70 and the timeto market by 90 3 However these equipments aretoo expensive for the small and medium sized enterprises SMEs and many techniques such as 3D CADsolid modelling RP process planning free form surfacesreconstruction etc require the high skilled personnelto complete Therefore it is especially difficultfor the SMEs to take full advantage of these technologiesin the product development process In order tooffer the support of rapid product development fornumerousSMEs manyRPservice bureaus SBs whichcan not only manufacture physical prototype and rapidtooling but also provide other engineering services have been established By 2001 there are more than500 SBs all over the world But not every SB canpossess all design and manufacturing capabilitiesrequired it must employ effectively the externalresource to better satisfy client requirements Namely a virtual enterprise which usually defined as a temporaryalliance of enterprises that come together to sharetheir skills core competencies and resource in order tobetter respond to business opportunities whose cooperationis supported by computer networks 4 6 is tobe founded Every SBconducts only the tasks of its corecompetencies and depends on numerous partners tocarry out the remaining tasks that this SB has no such manufacturing capabilities to accomplish in time While a new thought emphasizing service quality is becoming a basic strategy by which manufacturing industries can win global competition in the 21st century Teleservice engineering is an emerging fieldwhichaddresses service issue for manufacturers and customers As digital manufacturing technique progresses quickly digital service will be integrated seamlessly into the digital design and manufacturing system 7 The internet incorporating computers and multimedia has provided tremendous potential for remote integration and collaboration in business and manufacturing applications In order to provide a production collaborative environment for many SMEs and SBs to implement the networked manufacturing it is especially urgent for many SBs and SMEs to construct a service platform of networked manufacturing to speed up the product development process of the SMEs The rest of this paper is organized as follows Related research work is reviewed in Section 2 In Section 3 we introduce an integrated system of rapid product development based on RP Section 4 describes the workflow and functional design of the networked manufacturing service system The configuration of system running platform is presented in Section 5 In Section 6 we discuss the design of internet application A case study is demonstrated in Section 7 Finally Section 8 concludes the paper 2 Related research With the development of computer network and information technologies the networked manufacturing techniques are playing a more and more important role in manufacturing industry Substantial investments have been made to support the research and practice of 950networked manufacturing telemanufacturing or global manufacturing from both the academic community and industrial bodies all over the world in recent years A number of strategies and frameworks have been proposed Abdel Malek et al 8 described a structure within which a company can outsource several of its production and design activities via internet and developed a model to aid a company in selecting among the available technological and functional alternatives to maximize its flexibility Montreuil et al 9 presented a strategic framework for designing and operating agile manufacturing networks enabling to collaboratively plan control and manage day to day contingencies in a dynamic environment Tso et al 10 introduced the architecture of an agent based collaborative service support system which is able to carry out service requests in a manufacturing information network through some specially designed virtual agents Cheng et al 11 put forward an integrated framework for web based design and manufacturing which is developed based on Java solution and CORBA ORG broking technologies Offodile and Abdel Malek 12 introduced a framework for integrating IT and manufacturing strategies using the virtual manufacturing paradigm Huang et al 13 presented a holonic framework for virtual enterprises and control mechanisms of virtual enterprises under this framework O Sullivan 14 described an information architecture and associated toolset for understanding and managing the process of business development Akkermansa and Horstc 15 discussed managerial aspects of information technology infrastructure standardisation in networked manufacturing firms and presented a strategic framework to guide managers in making sensible decisions regarding IT infrastructure standardisation based on a number of pre existing economic and management theories such as transaction cost theory organisational design and IT maturity growth stages Jin et al 16 presented a research on key application technologies and solutions which includes a network safety strategy which ensures data transfer among the leaguer members production data management based on Web DOT distributed object technology and XML criteria which ensure data exchange in structure variance characteristic environments the network platform which provides the conversion service of different types of CAD files Woerner and Woern 17 introduced a new web service based platform providing developed methods for co operative plant production within virtual engineering To full realize the teleservice engineering in today s globalized manufacturing industry and meet the current market situation and customer demand a number of global manufacturing networks have been established by among others the Society of Manufacturing Engineer 18 Lockheed Martin AIMSNET 19 and 3M the 3M Innovation Global Network 20 Today s industries are facing serious structural problems brought about by their rapid development of overseas activities under a global integrated manufacturing environment Service and maintenance are becoming extremely important practices for companies to maintain their manufacturing productivity and customer satisfaction in foreign regions Due to the inherent problems of traditional help desk support some companies have started developing web based online customer service support system Foo et al 21 described an integrated help desk support for customer service via internet Lee 7 discussed the concept and framework of a teleservice engineering system for the life cycle support of manufacturing equipment and products A system for remote customer support has been created in the FCSA demonstrator of the Globerman 21 project 22 The purpose of these systems above is to provide effective and responsive remote support to customers in the use maintenance and troubleshooting of their equipment University of California is studying and developing a project called the Tele Manufacturing Facility TMF which is to create an automated RP capability on the Internet TMF allows users to easily submit jobs and have the system automatically maintain a queue While it can automatically check many flaws in STL files and in many cases fix them 23 RP potentially offers great benefits when used during the design and manufacturing process However RP must be used in an effective manner if these benefits are to be fully exploited The RP novices have a lot of difficulties in getting a global view of the RP technique and in tackling well founded decision for investment or outsourcing of RP tasks because of the very quick appearance of new and improved processes in this field In order to help novices select a suitable RP process the rapid prototyping system selector has been developed by many researchers 24 27 Quickparts com which is a privately held manufacturing services company dedicated to providing customers with an on line E commerce system to procure lowvolume and high volume custom manufactured parts has developed a QuickQuote system The QuickQuote system enables customers to get instant customerized quotations for the production of their parts 28 3D Systems Company which is the earliest and biggest RP equipment manufacturer has provided RP analysis of performance safety and reliability product prototyping for experimental evaluation and design modification Therefore any step of new product development process has a direct and strong influence on time to market A good product development of product design manufacturing selling and recycling at the early stage of a design cycle So that design iteration and changes can be made easily and effectively The more fluent the feedback is the higher possibility success of the system has Design for manufacturing DFM and concurrent engineering CE require that product and process design be developed simultaneously rather than sequentially 32 The integrated system of rapid product development is composed of three modules digital prototype physical prototype and rapid tooling and functional part manufacturing system The product development starts from the creation of a 3D model using a 3D CAD software package At that stage the product geometry is defined and its aesthetic and dimensional characteristics are verified The main function of digital prototype is to perform 3D CAD modelling The product and its components are directly designed on a 3D CAD system e g Pro Engineer Unigraphics CATIA IDEAS etc during the creative design process If a physical part is available the model can be constructed by the reverse engineering RE technique RE is a methodology for constructing CAD models of physical parts by digitizing an existing part creating a digital model and then using it to manufacturing components 33 RE can reduce the development cycle when redesigns become necessary for improved product performance Pre existing parts with features for improved performance can be readily incorporated into the desired part design When a designer creates a new design using mock up it is also necessary to construct the CAD model of the mock up for further use of the design data in analysis and manufacturing The three primary steps in RE process are part digitization features extraction and 3D CAD modelling Part digitization is accomplished by a variety of contact or non contact digitizers There are various commercial systems available for part digitization There systems range from coordinate measuring machine CMM laser scanners to ultrasonic digitizers They can be classified into two broad categories contact and non contact Laser triangulation scanner LTS magnetic resonance images MRI and computer tomography CT are commonly used non contact devices Contact digitizers mainly have CMM and cross sectional imaging measurement CIM Feature extraction is normally achieved by segmenting the digitized data and capturing surface features such as edges Part modelling is fulfilled through fitting a variety of surface to the segmented data points 34 In order to reduce the iterations of design prototypetest cycles increase the product process and manufacturing reliability it is necessary to guide in optimization of the product design and manufacturing process through CAE The CAD model can be directly converted to the physical prototype using a RP technique RP is a new forming process which fabricates physical parts layer by layer under computer control directly from 3D CAD models in a very short time In contrast to traditional machining methods the majority of rapid prototyping systems tend to fabricate parts based on additive manufacturing process rather than subtraction or removal of material Therefore this type of fabrication is unconstrained by the limitations inherent in conventional machining approaches 35 RP potentially offers great benefits when used during the design and manufacturing process It can help shorten time to market improve quality and reduce cost Over the last 10 years RP machines have been widely used in industry The RP methods commercially available include Stereolithgraphy SL Selective Laser Sintering SLS Fused Deposition Manufacturing FDM Laminated Object Manufacturing LOM Ballistic Particle Manufacturing BMP and Three Dimensional Printing 3D printing 36 etc RTis a technique that transforms the RP patterns into functional parts especially metal parts Furthermore the integration of both RP and RT in development strategy promotes the implementation of concurrent engineering in companies Numerous processes have been developed for producing dies fromRP system The RT methods can generally be divided into direct and indirect tooling categories and also soft firm and hard tooling subgroups Indirect RT requires some kinds of master patterns which can be made by conventional methods e g HSM or more commonly by an RP process such as SL or SLS Direct RT as the name suggests involves manufacturing a tool cavity directly on the RP system hence eliminating the intermediate step of generating a pattern 37 On the basis of abovetechniques a novel integrated system of rapid product development is to be established Its detailed structure is shown in Fig 1 4 The workflow and function design The workflow of the service system of networkedmanufacturing is shown in Fig 2 The first step is to log in to the website of SB Users have to enter their names and passwords Those without registration or authorization can also enter into the system but they are limited to viewing the information that is open to the public such as typical cases in this system The password entered by the user will be verified by the system After entering the SB website successfully the system will check the security level of users and determine which modules they can access or employ According to authentication for the system all usersa re to be divided into four categories general users without registration potential clients real clients and system administrator Received job requests from clients the SB will perform firstly process planning which fulfills the task decomposition and selects the most suitable process methods It is necessary for users to get the preliminary product quote and manufacturing time from the SB before the follow up process continues If such results may be accepted initially The SB will negotiate further with users by Video conferencing system Once come to term each other a contract is to be confirmed and the user becomes a real client The manufacturing tasks submitted by real clients had better be implemented in the SB However if the SB has no such manufacturing capabilities or can not accomplish then in time it is an effective way that the SB takes full advantage of external sources to carry out the remaining tasks The next step is to select the appropriate collaborative manufacturing enterprises to form a virtual enterprise to complete the tasks by the task assignment decision system In addition in order to monitor the manufacturing schedule to ensure smooth production both collaborative manufacturing enterprises and SB itself must provide as quickly as possible the essential information related to production progress and schedule for the module of product