Influence of information flow topology on closed-loop stability of vehicle platoon with rigid formation

Besides automated controllers, the information flow among vehicles can significantly affect the dynamics of a platoon. This paper studies the influence of information flow topology on the closed-loop stability of homogeneous vehicular platoon moving in a rigid formation. A linearized vehicle longitudinal dynamic model is derived using the exact feedback linearization technique, which accommodates the inertial delay of powertrain dynamics. Directed graphs are adopted to describe different types of allowable information flow interconnecting vehicles, including both radar-based sensors and V2V communications. Under linear feedback controllers, a unified closed-loop stability theorem is proved by using the algebraic graph theory and Routh-Hurwitz stability criterion. The theorem explicitly establishes the stabilization threshold of linear controller gains for platoons with a large class of different information flow topologies. Numerical simulations are used to illustrate the results.