Vehicle following control using front and back information based on vector Lyapunov function

With constant spacing safety policy in a platoon, the longitudinal control for vehicle following using front and back information in automated highway systems was studied. Based on the nonlinear dynamical model of vehicle, applying sliding mode control method, the longitudinal control laws for each vehicle in a platoon was designed depending on the information from the immediate predecessor, the immediate follower and the platoon leader available for feedback. By using vector Lyapunov function and comparison method, the string stability of a class of infinite nonlinear interconnected systems was investigated. Under the assumption that the systems be globally Lipschitz, under the conditions of stability of isolated subsystems, the new sufficient condition for exponential string stability of the class of interconnected systems was obtained. Based on the new results for the class of nonlinear interconnected systems, the stability domain of the controller parameters of string of vehicle was established. The results shows that, with the novel control method, convergence rate of spacing errors and velocity errors of the vehicle platoon is fast.