Abstract
在早期產品的概念設計階段，企業界往往為了引進自動化裝配系統而困擾，主要的問題在裝配技術的複雜度與特定性其導致了工程評估之可靠度降低。基於此理由，一個更有效率的成本評估方法應被建立以期滿足未來的需求。本研究之目的在提出一個成本模式以供早期設計階段能估算整個系統之生命週期成本，並做為設計改進的依據。然而傳統的評估方法往往需要有經驗的設計人員來支援。本研究之成本模式主要是針對專用機型之裝配系統來作探討，內容可分為兩大部份：一為系統之操作成本，另一為系統之產值。在成本估算上利用了 Boothroyd 的產品設計方法來得到主要的設備成本。 在此並不需要了解整個裝配系統的設計結構，只要能知道產品的組構就可以。藉由此方法不僅可得到整個產品生命週期成本之分配情況，而且還能明瞭產品之組裝程序。在成本模式的發展中，也將探討裝配系統的可靠度。在此考慮一些隨機或非固定的因子，例如系統的當機時間。另外，有關成本的績效指標將利用 " 生產力 " 來當衡量，以決定裝配系統之設計方案是否具有經濟效益。最後為了讓此成本模式更容易使用，將發展成一個電腦程式來輔助設計者作系統評估。另外將用一個例子來說明此方法將在不同裝配系統上之應用。During the introduction of an automatc assembly system, themain problems are the complexity of the assembly technology.As a result, the accuracy of the cost evaluation is low.The objective of this research is to propose a life-cycle costmodel for estimating the cost of an assembly system and formodifying the product design at the early design stage. Themodel does not require a lot of experience to use. In thisresearch, the cost model for the automatic assembly system isdivided into two parts. One is the cost of the systemoperation, and the other is the system yields. The costmodel combines Boothroyd's DFA method for estimating theinvestment cost at the product design stage. Once aproduct design is given, the total investment cost can beestimated by using this cost model. In this way, it canevaluate the overall life-cycle cost for all activitiesand provide an insight into the component design. For theconsideration of the system yields, the primary concernis on the system availability. Some stochasticparameters must be taken into consideration such as themachine failure time. An efficiency index (productivity) forthe cost performance measure is provided to show theprofitability of the different design alternatives. At last, acomputer program is developed to facilitate the evaluationprocess. Besides, an example is also given to illustratethe application of the model.