Modeling and logic controller specification of flexible manufacturing systems using behavioral traces and Petri net building blocks

This paper deals with the definition of a general approach to the modeling and control specification of flexible manufacturing systems (FMS). The development and the analysis of complex FMS models can greatly benefit from the automatic synthesis of the complete models and the availability of a graphic tool to describe them in a concise way. The automatic synthesis helps the designer to succeed in the error-prone task of building complex Petri net models or sequential functional charts, while the graphic representation makes it easier to understand them. The paper puts together a trace-based formal specification method and a compositional Petri nets approach with predefined building blocks, leading to a unified framework whose goal is to cope with the complexity of the FMSs behaviors and constraints. The problem of logic controller specification is also considered introducing in the behavior description the interaction with the environment via input and output signals.