A directed acyclic graph representation of routing manufacturing flexibility

This paper describes a graph-based model for representing routing flexibility in manufacturing systems. Routing flexibility is represented using direct acyclic graphs which enumerate all possible manufacturing operation sequences that can be applied to a certain part. Such a representation enables efficient planning of operations and machines according to different factors such as complexity of manipulation of the parts and current factory conditions. The routing representation is obtained through an interactive approach in which an expert human designer defines the specifications of a part and, using a software package developed by the author, constructs the routing models. The routing flexibility was embedded within a simulation model, offering a powerful analysis tool of flexible automation, both evaluating and measuring the effects of flexibility upon a manufacturing system's behaviour. An example illustrates the applicability and potentiality of the flexibility model developed. (C) 2000 Elsevier Science B.V. All rights reserved.