[雙語翻譯]產品設計外文翻譯--基于產品設計的制造成本建模（英文）

1、The International Journal of Flexible Manufacturing Systems, 12 (2000): 207–217 c ? 2000 Kluwer Academic Publishers, Boston. Manufactured in The Netherlands.Manufacturing Cost Modeling for Product DesignANGELA LOCASCIO S

2、upply Chain Operations Group, Motorola, Schaumburg, IllinoisAbstract. The process of product design is driven toward achieving design specifications while meeting cost targets. Designers typically have models and tools t

3、o aid in functional and performance analysis of the design but few tools and little quantitative information to aid in cost analysis. Estimates of the cost of manufacture often are made through a cost multiplier based on

4、 material cost. Manufacturing supplies guidelines to aid in design, but these guidelines often lack the detail needed to make sound design decisions. A need was identified for a quantitative way for modeling manufacturin

5、g costs at Motorola. After benchmarking costmodelingeffortsaroundthecompany,anactivity-basedcostingmethodwasdevelopedtomodelmanufacturing cycle time and cost. Models for 12 key manufacturing steps were developed. The fac

6、tory operating costs are broken down by time, and cost is allocated to each product according to the processing it requires. The process models were combined into a system-level model, capturing subtle yet realistic oper

7、ational detail. The framework was implemented in a software program to aid designers in calculating manufacturing costs from limited design information. Since the information tool provides an estimate of manufacturing co

8、sts at the design prototype stage, the development engineer can identify and eliminate expensive components and reduce the need for costly manufacturing processing. Using this methodology to make quantitative trade-offs

9、between material and manufacturing costs, significant savings in overall product costs are achieved.1. IntroductionAlthough the majority of a product’s cost, typically about 80%, is determined early in the design stage,

10、many decisions about the design are made during this stage with little knowledge of the effect on downstream cost centers. Manufacturing costs, in particular, are difficult to estimate and depend on many factors. Design

11、decisions that affect the cost to manufacture the final product often are based on rules of thumb or the urging of experienced manufacturing engineers. Several models attempt to quantify the “manufacturability” of a desi

12、gn. The popular Boothroyd-Dewhurst index, for example, builds an estimate of design manufacturability relative to factors such as assembly complexity and number of parts (Boothroyd, Dewhurst, and Knight, 1991; Boothroyd

13、and Dewhurst, 1983). Other models attempt to quantify design for X metrics to guide design decision making (Thurston and Locascio, 1994) or model trade-offs between design goals (Otto and Antonsson, 1991). These methods

14、provide an assessment of the worth of the overall design but, in their effort to remain generally applicable, do not necessarily capture the economic aspects of the design with the rigor needed for design decision making

15、. More often, these methods ask designers not only to be experts in the technical aspects of design but to understand how the design may affect other aspects in the product’s life cycle. Sullivan (1991) noted that a para

16、digm shift is occurring in engineering economy asMANUFACTURING COST MODELING FOR PRODUCT DESIGN 209? Will manufacturing cost increase by replacing one expensive component with four inexpensive ones?Although the factory e

17、ngineers had some qualitative ideas about the answers to these types of questions, they usually could not provide definite quantitative answers. Providing quantitativedataonhowmuchadditionalprocessingwillcostallowsthedes

18、ignertodecideif a less expensive part truly is less expensive when integrated with the product. There exists an opportunity to bring some engineering economic principles to practice in providing quantitative answers to t

19、hese design questions. In an effort to construct a suitable quantitative model, a benchmarking study was con- ducted of cost modeling tools used internally at Motorola. One conclusion was that the most complete and succe

20、ssful tools focused on the manufacturing processes in an activity- based fashion (Santina, 1996). We therefore decided on an activity-based costing (ABC) approach, where we focused specifically on the major factory proce

21、sses, or activities, that affected the development and manufacturing questions posed. In a typical ABC analysis, the operations usually are decomposed into small steps, as in motion studies. In this ap- plication, we dec

22、ompose the manufacturing process into only those activities that directly affect the design issues. The approach we take is to examine a particular printed wiring board and focus on the processing it requires. Costs are

23、assigned according to the time and human resources consumed at each process step. As the board acquires additional processing, more costs are incurred. Based on the factory time consumed and the cost associated with fact

24、ory operation over that time period, costs are allocated to the design. For example, in a typical surface mount manufacturing line that assembles components on the printed wiring boards used in most electronics, the fact

25、ory processes may be arranged as in figure 1. The processes shown constitute the majority of the processing, resources, and cycle time associated with assembling the printed wiring board. Several processes, such as buffe

26、rs and bar code readers, are not shown. The contribution of these processes to the overall manufacturing flow and cost is considered negligible in terms of their effect on the design issues. The processes considered for

27、this analysis are summarized in table 1. Note that not all processes are required for every product. The designer’s selection of components determines the specific process routing.3. Application to electronics assemblyTh

28、e 12 manufacturing processes detailed in table 1 represent the activities needed to be modeled individually and as a system working together to manufacture the product. For the individual processes, models of the factory

29、 time and human resources consumed are developed first. The process models must have enough detail to enable calculation of product cost to the individual component level. At the manual placement process, for example, a