Ptolemy is an environment for simulation and prototyping of heterogeneous systems. It uses modern object-oriented software technology (C++) to model each subsystem in a natural and efficient manner, and to integrate these subsystems into a whole. Ptolemy encompasses practically all aspects of designing signal processing and communications systems, ranging from algorithms and communication strat...

Ptolemy is an environment for simulation and prototyping of heterogeneous systems. It uses modern object-oriented software technology (C++) to model each subsystem in a natural and efficient manner, and to integrate these subsystems into a whole. Ptolemy encompasses practically all aspects of designing signal processing and communications systems, ranging from algorithms and communication strat...

This paper describes the Building Controls Virtual Test Bed (BCVTB) that is currently under development at Lawrence Berkeley National Laboratory. An earlier prototype linked EnergyPlus with controls hardware through embedded SPARK models and demonstrated its value in more cost-effective envelope design and improved controls sequences for the San Francisco Federal Building. The BCVTB presented h...

This paper defines Ptolemy. The novelty of Ptolemy is the notion of event types and quantification based on event types. We give the syntax, operational semantics and type rules for the langauge, and discuss its metatheory.

Process Networks in Ptolemy II

The Synchronous Reactive (SR) domain in Ptolemy II models systems as components with both infinite processing resources and infinite communication bandwidth. Computation within components and data transfer between components are considered to happen instantaneously. Therefore, a given system is simulated as if all of its components execute and produce outputs at the same time. This raises inter...

The Ptolemy project studies modeling, simulation, and design of concurrent, real-time, embedded systems. The focus is on assembly of concurrent components. The key underlying principle in the project is the use of well-defined models of computation that govern the interaction between components. A major problem area being addressed is the use of heterogeneous mixtures of models of computation. ...

We present Viptos (Visual Ptolemy and TinyOS), a joint modeling and design environment for wireless networks and sensor node software. Viptos is built on Ptolemy II, a graphical modeling and simulation environment for embedded systems, and TOSSIM, an interrupt-level discrete event simulator for homogeneous TinyOS networks. Viptos includes the full capabilities of VisualSense, a Ptolemy II envir...

In Ptolemy II, the widths of the relations between actors have an important role in specifying the semantics of a model. In some situations, however, explicit relation widths break the modularity of a model. In these cases, we would like to infer the widths of relations from the widths of neighboring relations. There is an existing implementation in Ptolemy, but it has some severe limitations. ...