Tool Integration of Ptolemy II

1
Tool Integration of Ptolemy II

• EE290N Class Project
• Haiyang Zheng
• May 15 2002

2
Outline

• Introduction and motivation
• Hybrid Systems
• Ptolemy II models
• Integration with Charon tool
• Hybrid Systems Interchange Format (HSIF)
• Conclusion

3
Introduction

• What is a Hybrid System?
• Hybrid Systems are widely used in control.
• Different tools are developed with different
  purposes modeling, simulation, verification
• Verification tools involve HyTech, Kronos,
  CheckMate, d/dt and Charon
• Tool integration has two functions
• Models validity checking
• Tools validity checking

4
Hybrid Systems

• Syntax
• Hybrid Automaton
• H lt S, V, C, P, T, Igt
• Discrete States
• Transitions
• Signals Channels
• Semantics
• State of a hybrid automaton
• Executions of an automaton

5
Ptolemy II

• Actor oriented design
• Block diagram with Actors, Ports and Relations
• Actors as producer/consumer components
• Models of Computation
• Messaging schema
• Flow of control
• Concurrency

Quoted from Prof. Edward Lees slides
6
Ptolemy II a hybrid system model
Quoted from Xiaojun Lius slides
7
Charon Tool

• An invariant verification tool using discrete
  approximations based on predicate abstractions.
• Invariants are the predicates on the continuous
  variables.
• The violations of the predicates on the abstract
  system result the counter-examples for double
  check on the concrete system.

8
Charon Tool Agent code
Composite Structure
9
Charon Tool Mode code
10
Tool Integration

• Integration of modeling, simulation tool with
  verification tool
• Construct Ptolemy II models from Charon models
• Construct Charon models from
• Ptolemy II models
• Demos

11
Problems so far

• Charon code is in text format, which makes the
  code parser fragile.
• Syntax change is even worse.
• Scalable issues
• HyTech, d/dt, CheckMate,

12
Hybrid Systems Interchange Format

• HSIF is to define an interchange format for
  hybrid system models.
• A descriptive language for hybrid system models.
• It has an XML format with according DTD.

Parser/Generator
Ptolemy II
Charon
HSIF

d/dt
CheckMate
13
Tool Integration via HSIF

• Syntax and semantics of HSIF are specified.
• It is a tree-like data-structure.
• Entities, Relations are included, but no Ports.
• Standard XML parser from Sun, JAXP is used.

• Demo

Ports ??
14
Conclusion

• A preliminary tool for the integration of Ptolemy
  II and the verification tool, Charon, was
  developed.
• A more general tool for the integration of
  Ptolemy II and other analysis tools with HSIF was
  partially developed.