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1、<p><b>  中文5496字</b></p><p><b>  附錄</b></p><p><b>  翻譯部分</b></p><p><b>  英文原文</b></p><p>  Introduction to Computer

2、 Integrated Manufacturing</p><p>  D .L.Goetsch</p><p>  CIM Defined</p><p>  Computer integrated manufacturing (CIM) is the term used to describe the modem approach to manufacturin

3、g. Although CIM encompasses many of the other advanced manufacturing technologies such as CNC; CAD/CAM, robotics, and just-in-time (JIT) deliuery, it is more th~ a new tech. noloml or. a ~c~ncept. ~puter integrat

4、ed :manufacturing is an entirely new approach to manufacturing, a new way of doing business.</p><p>  To understand CIM, it is necessary to begin with a comparison of modern and traditional manufacturing. Mo

5、dem manufacturing encompasses all of the activities and processes necessary to convert raw materials into finished products, deliver them to the market ,and support them in the field . These activities include the follow

6、ing:</p><p>  1) Identifying a need for a product.</p><p>  2) Designing a product to meet the needs.</p><p>  3) Obtaining the raw materials needed to produce the product.</p>

7、;<p>  4) Applying appropriate processes to transform the raw materials into finished products,</p><p>  5) Transporting products to the market.</p><p>  6) Maintaining the product to ens

8、ure proper performance in the field.</p><p>  This broad, modern view of manufacturing can be compared with the more limited traditional view that focused almost entirely on the conversion processes. The old

9、 approach excluded such critical preconversion elements 'as market analysis reseach, development, and design, as well as such after-conversion elements as product delivery and product maintenance. In other words, in

10、the old approach to manufacturing, only those processes that took place on the shop floor were considered manufacturing. Th</p><p>  With CIM, not only are the various elements automated, but the islands of

11、automation are all linked together or integrated. Integration means that a system can provide complete and instantaneous sharing of information. In modern manufacturing, integration is accomplished by computers. CIM, the

12、n, is the total integration of all components involved in converting raw materials into finished products and getting the products to the market.</p><p>  Historical Development of CIM</p><p>  

13、The term computer integrated manufacturing was developed in I974 by Joseph Harrington as the title of a book he wrote about tying islands of automation together through the use of computers. It has taken many years for C

14、IM to develop as a concept, but integrated manufacturing is not really new. In fact, integration is where manufacturing actually began. Manufacturing has evolved through four distict stages: </p><p>  Manual

15、 manufacturing.</p><p>  Mechanization / Specialization</p><p>  Automation.</p><p>  Integration.</p><p>  Manual Manufacturing</p><p>  Manual manufactur

16、ing using simple hand tools was actually integrated manufacturing.</p><p>  All information needed to design, produce, and deliver a product was readily available because it resided in the mind of the one pe

17、rson who performed all of the necessary tasks, The tool of integration in the earliest years of,manufacturing was the human mind of the craftsman who designed, produced, and delivered the product, An example of integrate

18、d manual manufacturing is the village blacksmith producing a special tool for a local farmer. The blacksmith would have in his mind all of the inform</p><p>  Mechanization / Specialization</p><p&

19、gt;  With the advent of the industrial revolution, manufacturing processes became both specialized and mechanized. Instead of one person designing, producing, and delivering a product, workers and / or machines performed

20、 specialized tasks within each of these broad areas. Commtmication among these separate entities was achieved using drawings, specifications, job orders, process plans, and a variety of other communication aids. To ensur

21、e that the finished product matched the planned product, the conc</p><p>  The positive side of the mechanization /specialization stage was that it permitted mass production, interchange, ability of parts, d

22、ifferent levels of accuracy, and uniformity. The disadvantage is that the lack of integration led to a great deal of waste.</p><p>  Automation</p><p>  Automation improved the performance and e

23、nhanced the capabilities of both people and machines within specialized manufacturing components. For example, CAD enhanced the capability of designers and drafters. CNC enhanced the capabilities of machinists and comput

24、er-assisted planners. But the improvements brought on by automation were isolated within individual components or islands. Because of this, automation did not always live up to its potential.</p><p>  To u

25、nderstandthe limitations of automation with regard to overall productivity impro- vement, consider the following analogy. Suppose that various subsystems of an automobile (i. e., the engine, steering, brakes) were automa

26、ted to make the driver's job easier. Automatic acceleration, deceleration, steering, and braking would certainly be more efficient than the manual versions. However, consider what would happen if these various automa

27、ted subsystems were not tied together in a way that allowed </p><p>  Integration.</p><p>  With the advent of the computer age, manufacturing has developed full circle. It began as a totally in

28、tegrated concept and, with CIM, has once again become one. However, there are major differences in the manufacturing integration of today and that of Design has evolved from a manual process using such tools as slide rul

29、esof manufacturing are linked together through the manual era of the past. First, the instrument of integration in the manual era was the human mind. The instrument of integratio</p><p>  Another way to view

30、 the historical development of ClM is by examining the ways in which some of the individual components of CIM have developed over the years. Such components as design, planning, and production have evolved both as proces

31、ses and in the tools and equipment used to accomplish the processes. pencils, scales, and erasers into an automated process known as computer-aided design (CAD). Process planning has evolved from a manual process using p

32、lanning tables, diagrams, and charts into</p><p>  These individual components of manufacturing evolved over the years into separate islands of automation. However, communication among these islands was stil

33、l handled manually. This limited the level of improvement in productivity that could be accomplished in the overall manufacturing process. When these islands and other automated components computer networks, these limita

34、tions can be overcome.</p><p><b>  MRP&CIM</b></p><p>  Material requirements planning (MRP) is an important concept with a direct relationship to CIM. It is a process that can b

35、e used to calculate the amount of raw materials that must be obtained in order to manufacture a specified lot of a certain product. Material requirements planning involves using the bill of material, production schedule

36、and inventory record to produce a comprehensive, detailed schedule of the raw,materials and components needed for a job.</p><p>  As manufacturing technology has evolved from automation to integration, MRP h

37、as also evolved. The acronym MRP now means manufacturing resources planning. This broader concept goes beyond determining material requirements to also encompass financial tracking and accounting. The modem version of MR

38、P is particularly well suited to the integrated approach represented by CIM. In this approach MRP can be an effective inventory planning and control tool.</p><p>  Key concepts relating to MRP include: 1. in

39、dependent and dependent demand; 2.lead times; and 3. common-use items. Independent demand resources are those that are not tied to any other resource , They stand alone .Dependent demand resources are tied directly to ot

40、her resources.Receiving a dependent resource without the other resources it requires does no good .In manufacturing,resources are more likely to be dependent than independent. Raw materials, in-procuress parts, component

41、s, and subassembl</p><p>  Lead times are of two types: 1. ordering lead time and 2. manufacturing lead time.Ordering lead time is the total amount of time between initiating a purchase order and receiving t

42、he order. Manufacturing lead time is the total amount of time required to perform all the steps necessary to produce a given part.</p><p>  Lead times are important because they are used in developing the sc

43、hedules for ordering materials and producing products. They are also where MRP is most likely to break down. Resource planners depend on the lead times provided to them by other personnel. If these times are padded or in

44、accurate, the MRP results will be equally inaccurate. Common-use items are items used in producing more than just one product. For example, the same type of aluminum sheet might be used in producing several differ</p&

45、gt;<p>  Manufacturing resources planning results in a variety of products of value to manufacturing managers in addition to the master schedule:</p><p>  products of value</p><p>  1) Re

46、lease notices that notify the Durchasinq department to place orders.</p><p>  2) Revise schedules showing updated due dates.</p><p>  3) Cancellation notices that notify appropriate personnel of

47、 cancellations that result from changes to the master schedule.</p><p>  4) Inventory status reports.</p><p>  Manufacturing resources planning is the most appropriateplanning approach for a CIM

48、 setting. When completely implemented it can result in a number of benefits:</p><p>  1) Inventory reduction.</p><p>  2) Quicker response to demand changes.</p><p>  3) Reductions

49、in setup costs.</p><p>  4) More efficient machine utilization.</p><p>  5) Quicker response to revisions to the master schedule.</p><p>  Automated Guided Vehicles</p><p

50、>  One advanced manufacturing technology seeing widescale use in CIM is the automated guided vehicle (AGV). As the world of manufacturing continues to evolve toward the fully automated factory, AGVs will play an incre

51、asingly important role.</p><p>  An AGV is a computer-controlled, driverless vehicle used for transporting materials from point to point in a manufacturing setting. In any discussion of AGVs, three key terms

52、 are frequently used:</p><p>  1) Guide path.</p><p>  2) Routing.</p><p>  3)Traffic management.</p><p>  The term guide path refers to the actual path the AGV follows

53、 in making its rounds through a manufacturing plant. The guide path can be one of two types. The first and oldest type is the embedded wire guide path. With this type, which has been in existence for over 20 years, the A

54、GV follows a path dictated by a wire that is contained within a path that runs under the shop floor. This is why the earliest AGVs were sometimes referred to as wire-guided vehicles. The more modern AGVs are guided by o&

55、lt;/p><p>  The term routing is also used frequently in association with AGVs. Routing has to do with the AGV's ability to make decisions that allow it to select the appropriate route as it moves across the

56、 shop floor. The final term, traffic management, means exactly the same thing on the shop floor that it means on the highway.</p><p>  Rationale for Using AGVs</p><p>  The reasons AGVs are espe

57、cially well suited to CIM are:</p><p>  1) AGVs are flexible because they can be computer-controlled.</p><p>  2)AGVs decrease labor costs by decreasing the amount of human involvement in materi

58、al handling.</p><p>  3) AGVs are compatible with production and storage equipment.</p><p>  AGVs can operate in hazardous environments</p><p>  AGVs c~ handle and transport hazardo

59、us materials safely.</p><p>  luctivity and, thereby, its competitiveness, all manufacturing systems must be flexible. lputer control makes AGVs more flexible.</p><p>  Flexibility is one of the

60、 keys to improved productivity in the modern manufacturing setting. It means the ability to adapt quickly to changes in products and processes brought about by the ever-changing demands of the marketplace. For a company

61、to maximize its productivity and ,thereby, its competitiveness,all manufacturing systems must be flexible .computer control makes AGVs more flexible than traditional materials handling systems. Another factor that intere

62、sts industrial engineers, manufact</p><p>  Another key feature of AGVs is that they are easily interfaced with existing production and storage equipment. Because they are so versatile ,they can be adapted

63、to be compatible with most production and storage equipment that might exist in a typical manufacturing setting. The AGVs also ar)Deal to industrial engineers, manufacmnng engineers, and manufacturing managers responsibl

64、e for producing products in hazardous or special environments. The AGVs that are designed to operate in a hazardous e</p><p>  Of the various reasons freauentlv cliven for using AGVs, perhaps the two that a

65、re the most important to the future of manufacturing are flexibility and compatibility. Their flexibility and compatibility allow AGVs to fit in with trends in the world of manufacturing includinq CIM Types of AGVs.

66、 </p><p>  There are six types of AGVs used in Csettings:</p><p>  1) Towinq vehicles.</p><p>  2) Unit load vehicles</p><p>  3) Pallet trucks.</p><p>  

67、4) Fork trucks.</p><p>  5) Light load vehicles.</p><p>  6) Assembly line vehicles. </p><p>  Monitoring of AGVs </p><p>  One of the shortcomings of an automated mate

68、rials handling system that relies principally~on AGVs is that a malfunction of one vehicle can cause problems throughout the entire system. Therefore, it is important that AGV systems be monitored closely and continually

69、. The ideal monitoring system is one that gives human operators instant, real-time feedback on the following:</p><p>  1) Location of all vehicles within the system</p><p>  2) Location of malfu

70、nctioning or inoperative vehicles</p><p>  3) Movement of vehicles.</p><p>  4) Amount of time vehicles spend</p><p>  5) Status of all vehicles in the system,loaded or unloaded.<

71、;/p><p>  6) Destination of all vehicles within the system.</p><p>  7) Status of the batteries in all vehicles within the system: charged, charging,or weak.</p><p>  The sophisticatio

72、n of the monitoring system is dictated by the sophistication of the overall AGV system .For example, AGV systems that tely on simple dispatch methods such as onboard dispatch or offboard call system dispatch require litt

73、le monitoring.</p><p>  This is because the human operators who use the onboard dispatch panel or offboard call box visually monitor routinely.However, AGV systems that use sophisticated central computer dis

74、patch methods require very close and continual monitoring because even the slightest programming error can cause problems throughout the entire AGV.</p><p>  The computer in design and Graphics</p>&l

75、t;p>  Computers are widely used in engineering and related fields and their use is expected to grow even more rapidly than in the past , Engineering and technology students must became computer literate ,to understand

76、 the applications of computer and their advantages ,Not to do so will place students at a serious disadvantage in pursuing their careers.</p><p>  Computer-aided design (CAD) involves solving design problems

77、 with the help of computer: to make graphic images on paper with a plotter or printer , analyze design data, and store design information for easy retrieval .many CAD systems perform these functions in an integrated mann

78、er , greatly increasing the designer’s productivity.</p><p>  Computer-aided design drafting (CADD),an offshoot of CAD , is the process of generating engineering drawings and other technical documents by com

79、puter and is more directly related to drafting than is CAD.the CADD user inputs data by keyboard and/or mouse to produce illustrations on the monitor screen that can be teproduced as paper copies with a plotter or printe

80、r.</p><p>  Engineers generally agree that the computer does not change the nature of the design process but is a significant tool that improves efficiency and productivity . The designer and the CADsysterm

81、may be described as a design team:the designer provides knowledge ,creativity, and control ; the computer generates accurate, easily modifiable graphics , performs complex design analysis at great speed, and stores and r

82、ecalls design information . Occasionally , the computer may augment or replace many o</p><p>  Depending on the nature of the problem and the sophistication of the computer system, computers offer the design

83、er or drafter some or all of the following advantages .</p><p>  Easier creation and correction of drawings. Working drawings may be created more quickly than by hand and making changes and modifications is

84、more efficient than correcting drawings made by hand.</p><p>  Better visualization of drawings . Many systems allow different views of the same objevt to be displayed and 3D pictorials to be rotaed on the C

85、RT screen .</p><p>  Database of drawing aids . Creation and maintenance of design databases (libraries of designs ) permits stoting designs and symbols for easy recall and application to the solution of new

86、 problems .</p><p>  Quick and convenient design analysis .Because the computer offers ease of analysis ,the designer can evaluate alternative designs,thereby considering more possibilities while speeding up

87、 the process at the same time .</p><p>  Simulation and testing of designs . Some computer systerms make possible the simulation of a product’s operation , testing the design under a variety of conditions an

88、d stess ,Computer testing may improve on or replace construction of models and prototypes.</p><p>  Increased accuracy. The computer is capable of producing drawings with more accuracy than is possible by ha

89、nd . Many CAD systems are even capable of detecting errors and informing the user of them .</p><p>  Improved filing . Drawings can be more conveniently filed ,retrieved, and transmitted on disks and tapes.&

90、lt;/p><p>  Computer graphics has an almost limitless number of applications in engineering and other technical fields . Most graphical solutions that are possible with a pencil can be done on a computer and us

91、ually more productively .Applications vary from 3D modeling and finite element analysis to 2D drawings and mathematical calculations</p><p>  Once the domain of large computer systems advanced can now be use

92、d to design a part or product, devise the essential production steps ,and electeonically communicate this information to and conteol the operation of manufacturing equipment , including robots .These systems offer many a

93、dvantages over traditional design and manufacturing systems, including less design effory control.</p><p><b>  中文譯文</b></p><p>  計算機集成制造的介紹</p><p>  D .L.Goetsch</p&g

94、t;<p>  計算機集成制造的定義</p><p>  計算機集成制造(CIM)是用來描述現(xiàn)代加工方法的術(shù)語。雖然CIM包括許多其他先進的制造方法諸如計算機數(shù)字控制(CNC)、計算機輔助設(shè)計/計算機輔助制造(CAD/CAM)、機器人學(xué)以及即時(JIT)交貨,但它仍不過是一項新技術(shù)或者是一個新概念。計算機集成制造是一種全新的制造方法,一條全新的經(jīng)營之道。</p><p>  

95、為了理解CIM,有必要從現(xiàn)代與傳統(tǒng)制造的比較開始?,F(xiàn)代制造包括所有把原材料變成成品、將它們送到市場以及在工地對它們進行保障所需的活動與工藝。這些活動包括如:</p><p>  1) 確定對于某一產(chǎn)品的需求。</p><p>  2) 設(shè)計一種產(chǎn)品來滿足這一需求。</p><p>  3) 獲取生產(chǎn)這種產(chǎn)品所需的原材料。</p><p>  

96、4) 采用適當(dāng)?shù)墓に嚢言牧献兂僧a(chǎn)品。</p><p>  5) 把產(chǎn)品運送到市場。</p><p>  6) 對這種產(chǎn)品進行維修以確保其在工地上的固有性能。</p><p>  可以把這種廣義的現(xiàn)代制造觀點與那種幾乎全部集中于轉(zhuǎn)換過程的更為狹義的傳統(tǒng)觀點進行比較。老方法將重要的轉(zhuǎn)換前的要素如市場分析研究、開發(fā)與設(shè)計以及轉(zhuǎn)換后的要素如產(chǎn)品交貨與產(chǎn)品維修排除在外。換句

97、話說,在老的制造方法中,只有那些發(fā)生在工廠的工藝才被認為是制造。這種傳統(tǒng)的把全面的概念分成若干個獨立的專門元素的方法基本上不會隨自動化的到來而改變。</p><p>  就CIM而言,不僅各種元素自動化了,而且自動化小島也被聯(lián)系在一起或集成。集成化意味著一個系統(tǒng)可以具有完全、瞬時的信息分享。在現(xiàn)代制造中,集成化由計算機完成。而CIM則是所有部件的全部集成,包括把原材料轉(zhuǎn)換成產(chǎn)品以及把產(chǎn)品送到市場</p>

98、;<p><b>  CIM的發(fā)展史</b></p><p>  計算機集成制造的術(shù)語在1974年由JosephHarrington作為一本書名提出的,書中他寫的是關(guān)于通過使用計算機把自動化小島連接起來。CIM作為一個概念發(fā)展已經(jīng)有很多年,</p><p>  但是集成制造確實不是初為人知。事實上,集成化竟然就在制造開始之處。制造的演變已經(jīng)經(jīng)歷了4個不同

99、階段。</p><p><b>  1) 手工制造。</b></p><p>  2) 機械化/專業(yè)化。</p><p><b>  3) 自動化。</b></p><p><b>  4) 集成化。</b></p><p><b>  手工制

100、造</b></p><p>  使用簡單的手工工具的手工制造實際上是集成制造。設(shè)計、制造和交付產(chǎn)品所需的所有信息都易于得到,因為它就存在于一個完成所有所需任務(wù)的人腦里。早些年制造的集成化工具是設(shè)計、制造和交付產(chǎn)品的技工的意愿。有一個集成化手工制造的例子是:鄉(xiāng)村鐵匠為當(dāng)?shù)剞r(nóng)民制造一種專用工具,在鐵匠的大腦里就要具有設(shè)計、制造和交付農(nóng)民工具所需的所有信息。在這個例子中,所有制造元素都是集成的。</p

101、><p><b>  機械化/專業(yè)化</b></p><p>  隨著工業(yè)革命的到來,制造工藝變得既專業(yè)化;又機械化?!辉偈且粋€人設(shè)計、制造和交付產(chǎn)品,而是工人和/或機床來完成這些寬廣的領(lǐng)域中的每個領(lǐng)域內(nèi)的專門任務(wù)。這些獨立機構(gòu)間的通訊是用圖紙、技術(shù)要求、任務(wù)書、工藝規(guī)程以及其他通信輔助手段來完成。為了保證成品件與計劃的產(chǎn)品相配,引入了質(zhì)量控制的概念。</p>

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