Safety Verification of a Controlled Cooperative Platoon Under Loss of Communication Using Zonotopes

This paper investigates the safety properties of a networked platoon of vehicles. The vehicles exchange information via a communication network that is subject to failure of single nodes or a complete loss of communication. An LMI-based controller is applied to maintain short distances between the vehicles. The system is modeled as a hybrid automaton, in which the continuous part represents the dynamical behavior of the platoon and the discrete part are spontaneous events related to the switching communication topology. For safety assessment, a reachability analysis of linear hybrid systems with uncertain inputs is applied. It consists of computing an approximation of the reachable set using zonotopes. In this paper, we propose a recursive scheme for the computation of the reachable set for hybrid systems with arbitrary transitions. We consider, as a study case, the worst case scenario corresponding to the transition from a fully functioning communication between the vehicles to a total loss of communication. We use the results of the verification to determine the minimum safe distances between the vehicles guaranteeing collision-free drive under network disturbances.