Scripting and Monitoring in TPN Designer Simulations: A Case Study using the Production Cell

TPN Designer (TPND) is a Java tool which allows visual modelling and discrete-event simulation of complex systems formalized as GSPN-like Petri nets. A model can be decomposed into a hierarchy of pages. A page is characterized by its input/output port interface and internal subnet which in turn can be structured into sub pages and so forth to any depth. Pages can be replicated to create pipeline or grid topologies. A scripting language is offered to "program" port interconnections and specify values of model parameters. A watch system is provided which allows common statistics to be extracted from observed behaviour of selected places and/or transitions. In addition, monitors, i.e. external aspect-oriented Java classes can be transparently weaved to a TPND simulation to associate model-sensitive actions to transition firings for general statistics computations. This paper demonstrates current features of TPND through a case study concerning a real-time system.