PHAVer: Algorithmic Verification of Hybrid Systems Past HyTech

  • Goran Frehse
Part of the Lecture Notes in Computer Science book series (LNCS, volume 3414)


In 1995, HyTech broke new ground as a potentially powerful tool for verifying hybrid systems – yet it has remained severely limited in its applicability to more complex systems. We address the main problems of HyTech with PHAVer, a new tool for the exact verification of safety properties of hybrid systems with piecewise constant bounds on the derivatives. Affine dynamics are handled by on-the-fly overapproximation and by partitioning the state space based on user-definable constraints and the dynamics of the system. PHAVer’s exact arithmetic is robust due to the use of the Parma Polyhedra Library, which supports arbitrarily large numbers. To manage the complexity of the polyhedral computations, we propose methods to conservatively limit the number of bits and constraints of polyhedra. Experimental results for a navigation benchmark and a tunnel diode circuit show the effectiveness of the approach.


Hybrid System Reachable State Hybrid Automaton Reachability Analysis Split Crit 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


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© Springer-Verlag Berlin Heidelberg 2005

Authors and Affiliations

  • Goran Frehse
    • 1
  1. 1.Dept. of Electrical and Computer EngineeringCarnegie Mellon UniversityPittsburghUSA

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