Using ProModel simulation language, a universal warehouse storage simulation model has been developed. Applications of the model have been executed with success to analyze the storage capacity and rack efficiency of a medium volume, low stock-keeping unit (SKU) warehouse and a medium volume, large SKU warehouse. The model is scaleable and can be modified to simulate any warehouse configuration, including selective racks, bulk floor storage, push-back, flow-through, drive-in and drivethrough racks.

This paper initially discusses the state-of-the-art and the current limitations in the modeling, scheduling and control of flexible automation. To model flexible automation, it is argued that the simulation tools must provide enhanced capabilities to consider both controller interactions and the flow of resources that support production.It is also demonstrated that scheduling and control must be considered concurrently in real-time to effectively manage flexible manufacturing systems (FMSs). The complexity of the modem FMS further requires that the integrated scheduling and control function must be distributed among several coordinators with the system. The second pti of the paper presents several research developments pertaining to the modeling, scheduling and control of flexible automation including: a Recursive, Object-Oriented Control Hierarchy for the integrated distribution of scheduling and control; a Hierarchical ObjectOriented Programmable Logic Simulator for the detailed modeling of FMSs; and a Hierarchical System Coordinator for implementing real-time scheduling and control. A physical emulator for an FMS which is being constructed is discussed as the example application in this presentation. Finally, the futureresearchplan and theeducationalprogram based upon the developments is outlined.

The current simulation tools which are based upon stochastic queuing network architectures have proven to be inadequate for modeling modem Flexible Manufacturing Systems (FMSs). A Hierarchical, Object-Oriented Programmable Logic Simulator (HOOPLS) is proposed: to model the interaction among the controllers which coordinate the production in an FMS; to address the flow of all entity types including jobs, fixturing, tooling, and information; and to provide direct consideration of the detailed processing plans which govern how resources are employed to manufacture a given item within the FMS.

This paper fust discusses an object-oriented, control architecture and then applies the architecture to produce a real-time software emulator for the Rapid Acquisition of Manufactured Parts (RAMP) flexible manufacturing system (FMS). In specifying the control architecture, the coordinated object is fmt defined as the primary modeling element. These coordinated objects are then integrated into a Recursive, Object-Oriented Coordination Hierarchy. A new simulation methodology, the Hierarchical Object-Oriented Programmable Logic Simulator, is then employed to model the interactions among the coordinated objects. The final step in implementing the emulator is to distribute the models of the coordinated objects over a network of computers and to synchronize their operation to a realtime clock. Specialized displays have also been developed to allow one to monitor the detailed, real-time operation of each coordinated object. The research will also convert the real-time emulation model into a real-time simulation model for the RAMP FMS. Both the real-time emulation and simulation capabilities will be demonstrated at the presentation. Real-TimeEmulation/Simulation Capability for the RAMP FMS