Modeling Control in Manufacturing Simulation

A significant shortcoming of traditional simulation languages is the lack of attention paid to the modeling of control structures, i.e., the humans or systems responsible for manufacturing planning and control, their activities and the mutual tuning of their activities. Mostly they are hard coded and dispersed throughout the model. Consequently, not only realism but also modeling flexibility and modularity is harmed. In recognition of this fact we consider a framework for simulation modeling that explicitly represents control structures. The framework is meant to serve as a conceptual basis for extending capabilities of simulation models, tools and libraries in analyzing manufacturing systems. It does so by capturing key-abstractions of the manufacturing field in terms of classes and their relationships. To study the practical relevance of the framework its concepts were implemented in an object-oriented simulation language and applied to a case example.