Safety Verification for Automated Platoon Maneuvers: A Case Study

A system consisting of two platoons of vehicles on a single track, plus controllers that operate the vehicles, plus communication channels, is modeled formally, using the hybrid input/output automaton model of Lynch, Segala, Vaandrager and Weinberg [7]. A key safety requirement of such a system is formulated, namely, that the two platoons never collide at a relative velocity greater than a given bound vallow. Conditions on the controller of the second platoon are given, designed to ensure the safety requirement regardless of the behavior of the first platoon. The fact that these conditions suffice to ensure safety is proved. It is also proved that these conditions are “optimal”, in that any controller that does not satisfy them can cause the safety requirement to be violated. The model includes handling of communication delays and uncertainty. The proofs use composition, invariants, levels of abstraction, together with methods of mathematical analysis.