Assume-guarantee reasoning for hybrid I/O-automata by over-approximation of continuous interaction

Abstract

Abstract-Assume-guarantee reasoning (AGR) is recognized as a means to counter the state explosion problem in the verification of safety properties. We propose a novel assume-guarantee rule for hybrid systems based on simulation relations. This makes it possible to perform compositional reasoning that is conservative in the sense of over-approximating the composed behaviors. The framework is formally based on hybrid input/output automata and their labeled transition system semantics. In contrast to previous approaches that require global receptivity conditions, the circularity is broken in our approach by a state-based nonblocking condition that can be checked in the course of computing the AGR simulation relations. The proposed procedures for AGR are implemented in a computational tool, called PHAVer, for the class of linear hybrid I/O automata, and the approach is illustrated with a simple example.

Contract-based integration of cyber-physical analyses

“…Frehse et al [9] develop assume-guarantee reasoning for hybrid systems based on over-approximation by simulation to enable compositional reasoning. A similar approach is taken by Girard and Pappas [11] using bisimulation, simulation, and language inclusion to develop approximate system relationships.…”

Tactical contract composition for hybrid system component verification

“…The single output port d (8) provides the current speed advice, which, by output guarantee π out rc (9), is never further away than D from the previous advice d − (10).…”

“…Thus, techniques to prevent state-space explosion are needed, such as assume-guarantee reasoning (AGR, e. g., [4,9,14]), which was developed to decompose a verification task into subtasks. Timed transition systems are used to approximate a component's behavior by discretization [9].…”

PHAVer: algorithmic verification of hybrid systems past HyTech

“…It is a very general framework that is based on (almost) arbitrary trajectories of a set of variables, which can have different dynamic types. Since our focus is on obtaining a computable framework for compositional reasoning, we have proposed a simple concept of I/O-automata in [9], which is largely based on the hybrid automata in [1]. Given a set …”

“…It can be used to verify equivalence or abstraction between different models, and for assume-guarantee reasoning. For lack of space, the reader is referred to [9] for further details on the approach.…”