In this article, a concurrent design procedure of a production system is presented, which supports the virtual commissioning between a real controller and a virtual plant consisting of virtual devices. To achieve the concurrency, we split a virtual device model into two parts, a physical device model (a geometric model with kinematics for the motion programming of tasks) and a logical device model (a behavioral model to interact with a real controller). The whole design procedure consists of four major steps: (1) process design, (2) physical device modeling, (3) logical device modeling, and (4) system control modeling. First, the process design step identifies effective manufacturing processes and produces the sequence of operations. Once the sequence of operations is obtained at Step 1, then the other three steps can be performed concurrently without interfering each other. All the three concurrent steps start from the sequence of operations, and a detailed procedure for each of the step has been developed. The concurrent attribute of the proposed design procedure significantly contributes to the saving of the delays in time to market. The proposed design procedure has been implemented and tested for various examples.

Presented in this paper is a FAB simulation framework considering the recipe arrangement problem of FAB tools. It is known that the WIP fluctuation is mainly caused by improper dispatching rules. Practical point of view, however, there is another cause of the WIP imbalance. We call the problem as a "recipe arrange problem of tools". A FAB consists of multiple tool groups, and each tool group has multiple tools (machine devices). Currently, FAB tools belonging to the same tool group are assumed to perform the same set of recipes (operations). Practically, however, this is not true. Since FAB tools are extremely sensitive, tools even belonging to the same tool group are assigned different recipes with high yield. We developed a simulation model including the recipe arrangement problem by modifying MIMAC6, and conducted simulation with SEEPLAN® developed by the VMS solutions. The simulation result shows that it is necessary to have not only dispatching rules, but also arranging rules are required to minimize the WIP fluctuations in a FAB.

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