The discrepancy between the benefits promised by the financial evaluation tools available for considering the cost/benefit tradeoffs of investment in flexible automation of manufacturing systems and the benefits realized in practice has arisen from such a number of shortcomings as "regardless of the diversity of approaches, researchers are not successful in quantifying strategic benefits ( of flexibility value) for use in financial justification models", "much less has been done to make these measures (of flexibility) operational", and "inconsistencies (exist) in the nomenclature of flexibility adopted by various researchers". So, in order to remedy some of these shortcomings, a new approach is proposed which analyzes the flexibility in manufacturing systems separately from the manufacturer's and the user's points of view and is based upon a basic perspective that the flexibility inherent in manufacturing systems is different from the flexibility that the user can attain after implementation. Thus the concepts of potential and realizable flexibility are introduced: the potential flexibility is classified into six elements and realizable flexibility into thirteen elements. A method is suggested for measuring each element of flexibility and for quantifying each element of the realizable flexibility in monetary terms (flexibility value). A financial evaluation model which integrates these quantified values in an attempt to narrow the "discrepancy" is also suggested. This model is implemented on an IBM compatible personal computer and on a workstation using C-Language, and two case studies - one selecting an automated mass manufacturing system for a passenger car manufacturer in Korea and the other comparing two flexible manufacturing systems - are carried out using this software, with encouraging results concerning the effect of flexibility value and the usefulness of the model for narrowing the "discrepancy".
In order to validate the basic perspective and the classification of flexibility, surveys have been carried out among users and manufacturers of automated manufacturing systems and empirical evidence is found that the potential flexibility is viewed by most of them as different from the realizable flexibility. Also empirical evidence is found that some elements of potential and realizable flexibility differ in importance depending upon production systems and our classification is essential. So it is suggested some elements of potential and realizable flexibility be given greater weight depending upon the requirements of the user and the manufacturer, and upon the type of production systems.
The organization of consensus meetings is suggested for obtaining the relevant data on flexibility value, for accurate and reliable evaluation, and for achieving consensus of the related persons and departments in preparation for the successful introduction of flexible automation in manufacturing systems. Finally shortcomings of present study are discussed and some recommendation are also made about areas where further study is needed.
