Averist: Algorithmic Verifier for Stability of Linear Hybrid Systems.

In this paper, we explain the architecture and implementation of the tool Averist that performs stability verification for linear hybrid systems. This tool implements a hybridization method for approximating linear hybrid systems by hybrid systems with polyhedral inclusion dynamics. It also implements a new counterexample guided abstraction refinement framework for analyzing the hybrid systems with polyhedral inclusion dynamics that are generated as a result of the hybridization. Some of the main features of our tool are as follows: (1) our tool is based on algorithmic techniques that do not rely on the computation of Lyapunov functions, (2) it returns a counterexample when it fails to establish stability, (3) it is less prone to numerical instability issues as compared to Lyapunov function based tools.