Ptolemy is an open-source and extensible modeling and simulation framework. It offers heterogeneous modeling capabilities by allowing different models of computation to be composed hierarchically in an arbitrary fashion. This paper describes modal models; which allow to hierarchically compose finite-state machines with other models of computation; both untimed and timed. The semantics of modal models in Ptolemy are defined in a modular manner.
Hierarchy; State machines; Modes; Heterogeneity; Modularity; Modeling; Semantics; Simulation; Cyber-physical systems
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