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Regarding the skills and roles in the team, it is good to understand production logistics as well as working with computer logic. Typical user profiles are layout planner, production engineers, lean manufacturing groups or dedicated simulation departments. For large industrial installations with database synchronization it is good to have a certain understanding of general software architecture.
Building complex factory models can be structured in 4 general phases. First the data collection including times, availabilities as well as layout and logistic control logic. Second the modeling itself, third the validation and verification of the model and finally the experiments and optimization using the validated model. The time depends very much on the task complexity and if it is a first project or a following project with predefined simulation objects or even libraries. The project duration can be from one week to several years.
After building the model in Plant Simulation you can analyze your production system to detect bottlenecks before they occur in reality or in existing systems. The most efficient solution can be determined. Typical key performance measures are the daily output, different kinds of costs and Throughput times.