ENTROPIC MEASUREMENT OF THE PROCESS PLANNING FLEXIBILITY

Manufacturing enterprises are facing nowadays an increasing demand for efficiency and flexibility. Flexibility is a general concept that represents their capacity to react to changes. It can be used in a variety of circumstances, allowing the definition of many types of flexibilities. This work presents a study of process planning flexibility and a methodology to measure it. Previous attempts to accomplish this measurement are applicable only to limited situations [2],[5], preventing their use in real shop floor conditions. It is the objective of this paper the presentation of a complete measurement algorithm and graph representation of the routes, both valid in all possible situations, in order to eliminate the limitations that presently exist. The graphic representation is a Petri-like net which shows the different technological states that a part goes through in each possible route. All the possible routes are represented and all the types of relationships among operations are taken into account. The algorithm has a function for each relationship, extending the concept of entropic measure of flexibility presented by Kumar [2]. Examples of calculation are given and a discussion of the results and of the application of the method are also included.