In: IEEE Trans. on Systems, Man, and Cybernetics - Part B, Vol. 28, No. 6, pages 770-780. 1998.
Abstract: The paper discusses how Petri nets may be used for the qualitative modeling of physical systems. The qualitative state of a system is represented by the marking of the net. The crossing of a landmark value corresponds to the firing of a transition. The paper gives a formal procedure to construct a Petri net model corresponding to a given set of qualitative equations. The approach can be used to study both autonomous systems and systems with forcing inputs. The dynamic behavior of the system can be studied as sequences of reachable markings of the net and can be computed with standard Petri net execution techniques. This approach also leads to a simple framework for the study of hybrid systems, i.e., systems whose behavior is described by both continuous and discrete event, i.e., systems whose behavior is described by both continuous and discrete event dynamics. Several examples, with applications to diagnostic and control, are fully discussed.
Keywords: Petri nets, discrete-event systems, hybrid systems, qualitative modeling.