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Design and Analysis of Integrated Manufacturing Systems (1988)

Chapter: Flexible Machining in an Integrated System

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Suggested Citation:"Flexible Machining in an Integrated System." National Research Council. 1988. Design and Analysis of Integrated Manufacturing Systems. Washington, DC: The National Academies Press. doi: 10.17226/1100.
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Suggested Citation:"Flexible Machining in an Integrated System." National Research Council. 1988. Design and Analysis of Integrated Manufacturing Systems. Washington, DC: The National Academies Press. doi: 10.17226/1100.
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Suggested Citation:"Flexible Machining in an Integrated System." National Research Council. 1988. Design and Analysis of Integrated Manufacturing Systems. Washington, DC: The National Academies Press. doi: 10.17226/1100.
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Suggested Citation:"Flexible Machining in an Integrated System." National Research Council. 1988. Design and Analysis of Integrated Manufacturing Systems. Washington, DC: The National Academies Press. doi: 10.17226/1100.
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Suggested Citation:"Flexible Machining in an Integrated System." National Research Council. 1988. Design and Analysis of Integrated Manufacturing Systems. Washington, DC: The National Academies Press. doi: 10.17226/1100.
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Suggested Citation:"Flexible Machining in an Integrated System." National Research Council. 1988. Design and Analysis of Integrated Manufacturing Systems. Washington, DC: The National Academies Press. doi: 10.17226/1100.
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Suggested Citation:"Flexible Machining in an Integrated System." National Research Council. 1988. Design and Analysis of Integrated Manufacturing Systems. Washington, DC: The National Academies Press. doi: 10.17226/1100.
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Suggested Citation:"Flexible Machining in an Integrated System." National Research Council. 1988. Design and Analysis of Integrated Manufacturing Systems. Washington, DC: The National Academies Press. doi: 10.17226/1100.
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Suggested Citation:"Flexible Machining in an Integrated System." National Research Council. 1988. Design and Analysis of Integrated Manufacturing Systems. Washington, DC: The National Academies Press. doi: 10.17226/1100.
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Page 42
Suggested Citation:"Flexible Machining in an Integrated System." National Research Council. 1988. Design and Analysis of Integrated Manufacturing Systems. Washington, DC: The National Academies Press. doi: 10.17226/1100.
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Page 43
Suggested Citation:"Flexible Machining in an Integrated System." National Research Council. 1988. Design and Analysis of Integrated Manufacturing Systems. Washington, DC: The National Academies Press. doi: 10.17226/1100.
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Page 44
Suggested Citation:"Flexible Machining in an Integrated System." National Research Council. 1988. Design and Analysis of Integrated Manufacturing Systems. Washington, DC: The National Academies Press. doi: 10.17226/1100.
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FLEXIBLE MACHINING IN AN INTEGRATED SYSTEM ARTHUR I. ROCH, J~ ABSTRACT Flexible manufacturing offers productivity, affordability, and en- hanced quality. Yet the far-reaching benefits are by no means automatic. Massive mod- ernization efforts can yield little net result in productivity improvement and cost reduc- tion without adequate consideration of the specific application. Integrated systems offer the greatest potential for productivity improvement, yet this benefit must be designed into flexible manufacturing system applications to ensure success. New methods must be assessed in terms of production needs. Technology can then be designed into the system in response to the potential costs and benefits of implementation. Integrating and imple- menting technologies in new flexible systems to meet program needs is proving effective throughout the aerospace industry. This paper describes an approach to the successful application of flexible manufacturing system capabilities. INTRODUCTION American industry stands at the gateway of a new era in manufacturing an era that began with the advent of hard automation. Transfer lines that were employed to re- duce the labor hours consumed in making a product are being replaced by systems with greater flexibility. Flexible automa- tion offers improved productivity and prod- uct affordability, yet it retains the benefit of improved quality that comes with hard automation. Not only does flexible auto- mation offer increased process speeds, it also permits users to adapt rapidly to changes in product or product mix. Furthermore, flex- ible automation can compensate for a de- cline in the number of skilled manufactur- ing professionals that are available for employment in American factories. With foreign competition an ever-increas- 34 ing threat to American industry, flexible manufacturing is becoming a critical ele- ment in the American approach to achiev- ing competitiveness in manufacturing. Au- tomation technology is moving out of the laboratory and into the workplace just when American industry needs it most. Flexible automation is particularly at- tractive to the aerospace industry. The aerospace marketplace is characterized by complex manufacturing requirements and small lot sizes. Capital investments that make sense in some industries—for exam- ple, automobile, farm equipment, and household appliance must be reexamined when a lot size is 100, as in aerospace. A well-designed, automated flexible manu- facturing system not only promotes eco- nomical production of small lot sizes but also eases the transition from one product to another.

FLEXIBLE MACHINING IN AN INTEGRATED SYSTEM The flexible machining system is the most prevalent form of flexible automa- tion in use today for a number of reasons: · Detailed part fabrication is easier to automate than assembly operations. · Machining is perhaps the most ma- ture detailed part fabrication technique. · The American machine tool industry has enthusiastically pursued the advent of such systems to make its equipment more attractive to potential customers. This paper addresses the broad subject of factory automation within the context of the aerospace industry. Machining systems are used as a practical example. The discus- sion concludes with the identification of crit- ical emerging technologies for the further application of flexible machining systems. Two such systems are discussed in this paper. The first is the Flexible Machining Cell (FMC) implemented by the LTV Air- craft Products Group (LTVAPG) in 1984. The second is the Integrated Machining System (IMS) that is currently under de- velopment at LTVAPG. This second- generation system is being developed using experience gained in establishing the first- generation FMC. The two systems provide substantial insight into the contents of a ge- neric factory automation life cycle. The fol- lowing sections describe this life cycle and relate the FMC and IMS to it. PLANNING THE SYSTEM Much has been written about the need for an overall implementation plan for the factory of the future. This paper assumes that those who would implement future factory automation systems will employ an architecture similar to that set forth by the Integrated Computer-Aided Manufactur- ing (ICAM) Project Priority 1105 (Air Force Wright Aeronautical Laboratories, 1984) and that they would embrace the philoso- phy of computer-integrated manufacturing (CIM). 35 The Factory Automation Life Cycle The soundest foundation for implemen- tation of a flexible machining system is a clearly identified and supported program need. Only with an unambiguous descrip- tion of what is to be produced can the proper questions be identified and the tech- nological answers determined. The life- cycle chain of events leading to a successful factory automation project involves a step- by-step process of design, analysis, and decision-making, with integral links be- tween product and program requirements, return on investment (ROI) analyses, and design development, as indicated in Figure 1. Successful development can be seen as the logical and progressive result of a series of carefully executed tasks each of which must be examined from both technological and financial perspectives. Candidate System The first challenge of implementation is identification of candidate systems. The ideal candidate factory automation system arises from thorough systems engineering analyses performed against specific pro- gram needs. The resulting concept is an ac- cumulation of system design responses that have been refined and validated through simulation and modeling routines. ' - ;3 r ~ T I INVESTMENT ANALYSIS I at| SYSTEM SPECIFICATION it> | COST/BENEF~ ANALYSIS | VENDOR `~p DEVELOPMENT SYSTEM ~FUNDING: ~ — , COST/BENEFIT VERIFICATION I F IMPLEMENTED SYSTEM it) | COST/BENEFIT TRACKING | NEXT GENERATION FIGURE 1 Factory automation life cycle.

36 System Specification Financially verified system design ele- ments are subject to further study during the development of specifications; the va- lidity of this assessment is dependent on a strong knowledge base of vendor capability and user insight. Major system elements are defined (and refined) through a series of documented development tasks. System specification begins by establish- ing a program office and generating a pro- gram plan. User support teams are then or- ganized to produce a System Requirements Document (SRD) and a Request for Propo- sal (RF P) to be released to prospective ven- dors. The REP includes formal specifica- tions for the desired system and its major elements, such as computer control, process equipment, and material handling. Ven- dors are selected on the basis of program- driven evaluation criteria mapped onto an evaluation matrix. Once a vendor is selected, specifications are reviewed and revised, as necessary, according to the selected vendor system. Concurrently, the integrated sys- tem elements are verified through simula- tion and modeling. The SLAM simulation language (Pritsker and Pegden, 1979) was used for this pur- pose, with user-written logic added to mimic the proposed scheduling logic. The primary uses of the model were to compute equipment and tooling capacity require- ments, to develop and validate scheduling policy, and to serve as a focal point for documenting and resolving operating issues during the design phase. In general, the methods and issue resolu- tion role of simulation are often overlooked relative to the more quantitative type of output. The accuracy of the quantitative results e.g., utilization, span times is, of course, sensitive to the quality of the input data. This presents some problems when new technology is involved and when the methods and time data are poorly defined. A good reference on the use of simulation ARTHURJ.ROCH,JR. in practice is Pope's discussion on the gen- eral role of simulation in aerospace manu- facturing (Pope, 1986~. Cost/Benefit Analysis While system specifications are being de- veloped, a thorough cost/benefit analysis is performed to reaffirm the bottom line of implementation maintaining an accept- able ROI. This analysis narrows estimates for the standard-hour content of expected part loads as well as nonrecurring costs. Based on vendor proposals, the ROI is computed on the basis of an accepted mod- el, and a capital expenditure is sought and approved. In approving the expenditure, management must consider the potential factory automation initiative from both technical and financial perspectives. The technology employed must be packaged into a sound business proposition. The use of a cost center approach has sim- plified the task of properly accounting for costs associated with flexible machining sys- tems. By creating discrete cost centers rather than relying on manufacturing pools, the flexible machining system is in a position to capture all costs associated with its opera- tion. This accumulation of charges negates the dependence on overhead allocations based on diminishing amounts of direct la- bor. Although this practice satisfies the need for actual cost collection, it is not directly comparable with costs that would be ex- pected for conventional machining systems, which have relied on pool rates and over- head allocations. This constitutes one of the basic difficulties in conducting financial analysis of flexible machining system instal- lations. The creation of a synthetic present- technology cost center with conventional machining will allow a direct comparison without reliance on pool rates that may be either over- or under-inflated in relation to rates for the actual equipment replaced. The basic measure of the flexibility of a cell can be quantified by an examination of

FLEXIBLE MACHINING INANINTEGRATED SYSTEM how many discrete part numbers can be produced in the cell. The larger the number of different part numbers produced, the greater the flexibility of the cell. The cost- effect;iveness of this flexibility can be di- rectly related to the amount of resources necessary for the described part population. If the flexibility of a cell is limited to only 6 discrete parts from a population of 18, there is a need for 3 times the resources, in terms of capital, maintenance, direct head count, etc., than that needed for a cell that has the capability of handling the full population. Likewise, when compared with conven- tional stand-alone machining, the highly versatile flexible machining system uses less of these same resources to meet the machin- ing needs of a given part population. These resources all have a cost that is both quan- tifiable and measurable. Development System The next step in the factory automation life cycle is the selection of a vendor and the commitment of capital resources. This ac- tion formally initiates the development pro- cess and gives the proposed system an upper management, and even corporate, visibil- ity. The transition from business-as-usual to state-of-the-art must be carefully orches- trated. At this stage of development, many tech- nical disciplines from the purchasing com- pany and from the system suppliers must work in tandem to prepare facilities and establish interfaces to other operations. Users receive training, start-up resources are ar- ranged, and numerical control nro~r~m~ are built and proofed. Cost/Benefit Verification Even as vendors and functional depart- ments become absorbed in converting the system into a reality, ROI remains the pri- mary test for each decision. As the devel- opment system begins to take shape, contin- 37 uing cost/benefit verification is performed. Detailed estimates of standard-hour contents and actual vendor costs are computed, and nonrecurring costs are refined. Standard- hour content for new systems is derived from parametric estimates of existing machining standards adjusted for anticipated produc- tivity improvements. This development con- stitutes the standard-hour content for a given part population that will be run in the new system. Adjustments or revisions are made as experience is garnered from actual system performance. This concurrent analysis, even at this early stage, allows design and operational changes to be made to ensure that the capital expenditures will be justified by the intended productivity improvement. Implementing the System A program team, composed of technol- ogy specialists and users with internal and external resources at their disposal, must be made responsible for implementing the sys- tem. This operational milestone, the crea- tion of the program team, is signaled by a formal sign-over of the system's operation and control from the developing and imple- menting technology specialists to the orga- nization~s) that will be responsible for op- erating the system. Technical support is ongoing as the pro- gram team provides analysis and system de- bugging. Corrections and enhancements to software and hardware design, as well as facilities, are identified and coordinated by the program team. Modernization special- ists continue in a consulting capacity to help the user organizations achieve and main- tain productivity targets. Cost/Benefit Tracking Once the system is implemented, cost/ benefit tracking can be based on real stan- dard-hour performance along with actual recurring and nonrecurring costs. These

38 data, tracked and maintained for the life of the system, provide the means to verify and sustain the ultimate factory automation life cycle goal of an acceptable ROI. OPERATIONAL EXPERIENCE WITH A FLEXIBLE MACHINING CELL The validity of the generic factory auto- mation life cycle is demonstrated daily in LTVAPG's Flexible Machining Cell devel- oped using the techniques described. The FMC became operational on July 2, 1984. The cell currently machines 568 different B-1B aft and aft-intermediate fuselage parts, with an economic order quantity of one. FMC has demonstrated a 3-to-1 productiv- ity improvement ratio over conventional machining. Figure 2 shows the cell layout and current factory-floor view of this 40,000- square-foot facility. As a first-generation flexible manufactur- display. ing system, the FMC provides state-of-the- art capabilities for the manufacture of de- tailed machined parts. The cell provides · Total computer control by means of a centralized system · Automated machining (drilling, bor- ing, tapping, milling, and profiling) in one setup · Automated pallet transport and ma- chine loading and unloading · Automated in-line part cleaning and inspection · Centralized coolant and chip segrega- tion and removal · Computerized cell loading, schedul- ing, simulation, and cutting-tool control · Palletized part loading and unloading at automated pickup and delivery stations · Centralized electronic cutting-tool gauging and setup · Cutter diameter compensation for nu- merical control programs · Optimized part-family and tooling re- lationships · An exceptional part mix and volume in an essentially unmanned environment ARTHURJ.ROCH,JR. Implemented to meet specific detailed machined part needs for the B-1B program, the cell consists of Automated work changer carousels · Machining centers Chip and coolant system Material handling system Cleaning module Inspection modules · Automated storage and retrieval sys- tem for cutting tools Computer control system . Two 10-station carousels, obtained from Cincinnati Milacron, are employed to queue work in the load-unload area. In addition, each of the carousels has two load-unload stations. These stations are staffed by oper- ators who receive their instructions from the computer control system through a CRT Cincinnati Milacron also provided the eight unmanned computer numerically con- trolled (CNC), single-spindle machining centers contained in the FMC. The centers are capable of machining both aluminum and nonaluminum materials in four axes. Each center is equipped with an automatic tool changer with 90 cutter storage posi- tions. The prismatic work area has maxi- mum dimensions of 32 by 32 by 36 inches and a pallet load weight capacity of 5,000 pounds. Each machining center offers the capacity for three-axis and four-axis simul- taneous contouring in the X, Y. Z. and B axes. In addition, the centers provide torque-controlled machining at variable spindle speeds ranging from 40 to 5,000 rpm. The centers are designed so that the actual machining operation takes place in an enclosed area, and thus chips and cool- ant are more easily collected and present less of an adverse impact on the factory environment. A five-station automatic pallet shuttle system is built into each machining center to allow almost continuous machining op- erations. Spindles can be equipped with

FLEXIBLE MACHINING INANINTEGRATED SYSTEM 39 ATE lAL REVIEW —- ELEVATED STATION CRT __ CELL CONTROL R | . 20It.x26 It. ~. ~ '" _ , U ~ ~ :~ :- Hi, FIGURE 2 Flexible machining cell layout: (top) schematic, (bottom) factory-floor view.

40 ARTHUR J. ROCH, JR. part surface sensing probes to verify blanks working in conjunction with the AS/RS. with loaded CNC programs and establish Comprehensive electronic control of cut- first-cut positioning. The centers are also capable of automatically detecting broken tools and thus contributing to a reduction in scrap and rework. A central chip and coolant system, de- signed by Henry Filters, Inc., is used for chip and coolant removal and collection from all machining centers and the clean- ing module within the cell. Chip collection is accomplished without human interven- tion through the use of a dual-flume system installed in the FMC floor. A dual-flume chip and coolant system allows for the sen- . ~ , . — — ~ . . . aration of aluminum and nonaluminum chips. Pallet handling within the FMC is pro- vided by a system of battery-powered, com- puter-controlled, wire-guided transport carts. The self-propelled carts, supplied by Eaton-Kenway, are under the control of their own computer, which is directed by the FMC host computer. The carts trans- port the pallet loads to and from the car- ousel pickup and delivery stations as well as to and from the other cell modules. The Taylor and Gaskin, Inc., cleaning module houses an unmanned automated liquid- wash and air-dry operation for preinspec- tion cleaning of machined parts. The two inspection modules, designed by Digital Electronics Automation, include electromechanical automated coordinate measuring machines for part geometry veri- fication. Both cleaning and inspection mod- ules are directed by the FMC host computer by means of specialized controllers using distributed numerical control programs. A cutter crib automated storage and re- trieval system (AS/RS) is located within the cell, as is the site of electronic cutter gaug- ing and setup. Each cutter is logged into the FMC, given a bar code label, and com- puter controlled from that point forward. The cutter's dimensions, location, use, and maintenance are all monitored and di- rected by the cell's computer control system tiny tools is combined with compensation in numerical control programs for cutter dimensional variances due to wear. Tool use is maximized, while part quality is en- hanced and scrap is reduced. The LTVAPG FMC produces more part numbers with less manual intervention than any other such manufacturing cell in the world. The software and its associated com- puter system are designed so that the cell operates without manual intervention ex- cept at the load-unload stations. Productiv- ity gains afforded with FMC are the result of reduced human intervention, improved material handling, enhanced throughput, and maximized control. The computer con- trol system is the focal point of the cell's suc- cess. The unique FMC software architecture represents a new philosophy in computer control design. The master machining sched- ule is created by LTVAPG's business host computer. The FMC's control computer, a DEC 11/44, receives a 20-day window of work orders on a daily basis from the busi- ness host. The downloaded work orders are assessed, selected, and scheduled into the FMC by the computer control system. When the data are downloaded to the FMC computer, the workload is automati- cally assessed to maximize use of machining center resources. This optimization includes detailed consideration of · Due date · Priority · Material availability · Numerical control and inspection part program availability · Cutting tool requirements · Fixtures and pallets · Machining time From the downloaded work orders, the FMC computer system selects enough work orders for a 24-hour production run. The FMC software analyzes the workload to ob- tain a 24-hour schedule for the cell's opera-

FLEXIBLE MACHINING IN AN INTEGRATED SYSTEM lion. The scheduler optimizes the 24-hour period to meet the production schedule, minimize cutter tool changes, maximize ma- chine use, and reserve a selection of parts with high machining times for fabrication on the unmanned third shift. FMC production capabilities are appli- cable to all aerostructures programs requir- ing aluminum and steel machined detail parts sized within the cell's work envelope. Flexibility in scheduling and operations provides detail parts in any quantity with- out penalties for short lead time or small quantities. The FMC was developed and imple- mented under a Category 1, Phase III B-1B Subcontractor Technology Modernization Program. Internal funding provided devel- opment and implementation costs, with indemnification arranged through Rock- well International and the U.S. Air Force. As a cornerstone of LTVAPG's Multiprod- uct Factory of the Future, the FMC offers unparalleled flexibility in part load and quantity, substantial production savings, superior part quality, and exceptional per- formance. A SECOND-GENERATION FLEXIBLE MACHINING SYSTEM The success of the FMC has spawned new opportunities as a new generation of aero- structures evolves. A rapid change in aero- space manufacturing materials from con- ventional to exotic metals demands that a second-generation system, the Integrated Machining System, be implemented. This second-generation system, although promising significant alterations in shop- floor activity, will make its greatest impact above the shop floor. The move to auto- mate above the shop floor, first with FMC's control computer and now in the IMS, re- quired LTVAPG to structure an informa- tion and function architecture that embraces total factory control. This hierarchical schema, shown in Figure 3, interprets inte- 41 grated computer-aided manufacturing in terms of program requirements and produc- tion needs. Control is driven to the lowest possible manufacturing level, permitting modular implementation of future systems, maximizing resource distribution and track- ing, and optimizing information flow. Simultaneously with FMC implementa- tion, LTVAPG began preliminary studies of advanced manufacturing technology ap- plications to future large-part and exotic- metal machining requirements. The result- ing IMS concept, as shown in Figure 4, focuses on extending FMC manufacturing expertise to medium- and large-profile ma- chined parts. The fabrication requirements for future metals, as found in candidate IMS parts, demand the use of five-axis computer numerically controlled high-speed machin- ing (HSM) for aluminum and high-through- put machining (HTM) for titanium. The most notable benefit of applying HSM and HTM technologies is the reduc- tior1 of detailed part cutting time that will be afforded by next-generation spindles. HSM is projected to achieve a 6-to-1 im- provement ratio, and HTM will afford a 2-to-1 improvement ratio. Furthermore, the productivity advantage of the spindles will be complemented by automated upstream preparatory tasks and downstream inspec- tion and cleanup tasks. The Ingersoll Milling Machine Company is under contract for turnkey implementa- tion of IMS, with production start-up sched- uled for early 1989. The IMS will require a floor area of approximately 150,000 square feet. The IMS will encompass the functions for machined detail part fabrication of su- perplastically formed parts, castings, forg- ings, and plate stock, from the receipt and storage of raw material through the final unloading and tagging of a finished detail part, ready for hand finishing, nondestruc- tive inspection, or processing. The IMS will incorporate design of a hierarchical compu- ter control system to integrate the machin-

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FLEXIBLE MACHINING INANINTEGRATED SYSTEM ing functions with its support functions, as shown in Figure 3. In addition, it will con- trol resources shared with LTVAPG's FIex- ible Machining Cell (FMC I). The follow- ing functions will be addressed in the IMS design for a second-generation Flexible Ma- chining Cell (FMC II): · Automated storage and retrieval sys- tems for work-in-process (WIP), cutter components, and cutter assemblies · Automated storage of pallets and fix- tures · Material handling systems for the transfer of WIP and cutters · Cutter assembly buildup, preparation, and gauging · Load-unload stations for pallets, fix- tures, and parts · Five-axis HSM of aluminum · Five-axis HTM of titanium · Automated washing · Automated dimensional inspection · Automated chip collection and chip transfer The IMS project's primary design objec- tives are to apply leading-edge machining technology to · Increase productivity of the LTVAPG machine shop in the fabrication of large, multiaxis aluminum and titanium parts · Decrease WIP inventory of high-value material · Reduce the direct cost per unit of out- put · Improve product quality · Improve throughput · Promote timely delivery of parts to as- sembly Productivity improvements resulting from IMS implementation will be the result of synergistic equipment and control oper- ations along with advanced machining technology. Overall improvement estimates range as high as 6 to 1 over conventional methods. 43 FUTURE OPPORTUNITIES Sufficient technology exists today to per- mit flexible machining system implemen- tation. However, a number of emerging technologies will soon be available for in- corporation into even more sophisticated flexible machining systems. These emerging technologies include Adaptive control Automatic cutter wear compensation · Automatic broken too} detection In-process verification Robot-controlled debarring · Automatic noncontact dimensional in- spection · Advanced cutting tools · Generative process planning · Computerized generation of as-manu- factured configuration Integration of these technologies with those existing today will result in a synergy that will further propel flexible machining systems into the mainstream of American manufacturing. The design and application of such sys- tems will continue to offer many challenges and uncertainties. To maintain focus on the task, the factory automation life cycle, as described in this paper, presents an abbre- viated road map in the development pro- cess. Once one has started down the road to automation, it becomes difficult to identify stopping points. Focusing on productivity through repeated assessment of ROI pro- vides the necessary signal. The system's ROI must define the level of automation. Design development in the factory automation life cycle must be driven by continuing cost/ benefit assessment. The level of automation in the ultimate flexible machining system design is thus controlled through dynamic ROI assessment. A successful system enhances profits and provides a competitive advantage. First- generation applications emphasized shop-

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FLEXIBLE MACHINING IN AN INTEGRATED SYSTEM floor automation ant] reduced production labor costs. These early efforts must be fol- lowed by second- and third-generation sys- tems that focus on automation and inte- gration of above-the-shop-floor activities, where a greater percentage of product costs Is encountered; thus, modernization bene- fits are expanded. Tociay's flexible machining systems ap- plications are the forerunners of true com- puter-integrated manufacturing. CIM is es- sential to financial survival for American industry in the l990s and beyond. In this new era of manufacturing, successful com- panies will be those American firms that cleveloped long-range plans in the 1980s and pursued evolutionary implementation of 45 those plans on the basis of specific business opportunities and technology applications. REFERENCES Air Force Wright Aeronautical Laboratories. 1984. ICAM Conceptual Design for CIM. Final Techni- cal Report, AFWAL-TR-84-4020, Air Force Sys- tems Command, Wright-Patterson Air Force Base, Ohio. Pope, D. N. 1986. The role of simulation in aerospace manufacturing. Pages 2-97 in Proceedings, Vol. II, SME Ultratech Conference, Long Beach, Califor- nia, September 1986. Dearborn, Mich.: Society of Manufacturing Engineers. Pritsker, A. A. B., and C. Pegden. 1979. Introduction to Simulation and SLAM. New York: Wiley.

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Design and Analysis of Integrated Manufacturing Systems is a fresh look at manufacturing from a systems point of view. This collection of papers from a symposium sponsored by the National Academy of Engineering explores the need for new technologies, the more effective use of new tools of analysis, and the improved integration of all elements of manufacturing operations, including machines, information, and humans. It is one of the few volumes to include detailed proposals for research that match the needs of industry.

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