Distributed adaptive longitudinal control for uncertain third-order vehicle platoon in a networked environment

The longitudinal control for a platoon of connected and automated vehicles is a popular topic in transportation engineering, nowadays. However, a majority of existing results about the cooperative/distributed platoon control are based on linear models that are derived from nonlinear vehicular dynamics by exact feedback linearization. This nonlinear-linear transformation asks for a complete priori knowledge of vehicular dynamics, which could be difficult to obtain in practice. To overcome this disadvantage and address multiuncertainties including both unknown plant parameters and unknown control coefficients in third-order vehicular node dynamics, this paper proposes a distributed backstepping control scheme in a networked environment. Unknown parameters are identified online, and both internal stability and string stability for constant distance spacing policy are established. Simulation studies are carried out by comparing the adaptive control proposed in this paper with the robust control in the state-of-the-art algorithms.