Hierarchical decision making in computer integrated manufacturing systems

This paper describes a hierarchical approach for decision making and production management in manufacturing systems. Decision making problems in such an environment are complex owing to large dimensionality, wide variety of decisions of varying scope, focus and time-horizon, as well as the presence of random disturbances. A hierarchical approach decomposes the global problem into a series of top-down sub-problems. We propose a multi-layer hierarchical decomposition which is dependent on the complexity of the problem. Aggregation schemes for model reduction have been developed and blended with the time-scale decomposition of activities to provide the basis of the architecture. We present a systematic stepwise design methodology for the construction of the decision making hierarchy, and explain the subsequent operation of the hierarchy in an unreliable environment. Finally, the integration of this architecture with a CIM information system as a means to effectuate timely and consistent decisions.