Modelling and scheduling of a flexible manufacturing system

Production scheduling of an FMS is formulated as a multi-level integer program. The hierarchical decision structure is proposed which includes the following problems: (i) part type selection-determining a subset of part types for simultaneous processing; (ii) machine loading-the allocation of operations and required tools among the machines; (iii) part input sequencing-determining the sequence and timing of release of parts to the system; (iv) operation scheduling-determining the detailed schedule for processing the parts in the system. The integer programming formulations for all these problems are presented as well as the solution algorithms for part sequencing and operation scheduling. A simple numerical example illustrates the approach proposed, and some computational results are reported.