A queueing network approximation of semiconductor automated material handling systems: how much information do we really need?

Queueing networks are sometimes used to model material handling in flexible manufacturing systems. We explore the use of a closed queueing network model to approximate an intrabay automated material handling system (AMHS) in semiconductor manufacturing. Rather than solving the model analytically, we propose simulating it. Current industry models are very complex and require long development and run times. The simulated approximation can be used as an easy and fast alternative. To compare the approximation with the detailed models in use, we employ an information taxonomy to classify AMHS models based on the amount and types of information needed to model the system, and to obtain desired output. This classification aids modelers in determining the level of detail to incorporate in a model based on the objectives of the simulation study.