Fuzzy assessment of machine flexibility

Manufacturing flexibility is a difficult and multifaceted concept that because of its inherent complexity and fuzziness is amenable to an artificial intelligence treatment. Fuzzy logic offers a suitable framework for measuring flexibility in its various aspects. This paper deals with the measurement of machine flexibility. When data are precise, this is done via a simple analytical formula. But if such data, and hence knowledge, are not precise, fuzzy-logic modeling should be employed by transforming the human expertise into IF-THEN rules and membership functions. An implementation of the interval-valued fuzzy-set approach, together with a max-min schema, provides the approximate inference mechanism for the computation of machine flexibility. This approach has the advantage of revealing second-order semantic uncertainty with the associated nonspecificity measure. The models are illustrated with a number of examples.