Operations planning and scheduling problems in advanced manufacturing systems

Operations planning and scheduling (OPS) problems in advanced manufacturing systems, such as flexible manufacturing systems, are composed of a set of interrelated problems, such as part-type batching, machine grouping, tool loading, routing, part input sequencing and on-line scheduling. In this paper, an integrated, simulation-based approach to the OPS problems is discussed. A detailed simulation model is developed using FORTRAN and SLAM II which integrates loading, part inputting, routeing and dispatching issues of the OPS. An experimental frame is developed which provides statistical analysis of the simulation output by developing an experimental design. Several hypotheses concerning a number of system parameters (e.g. loading strategies and scheduling rules) were developed and statistical analysis (e.g. ANOVA and MANOVA) are performed on a set of performance measures, such as mean flow time, mean tardiness, system utilization, and maximum tardiness.