Robust longitudinal velocity tracking of vehicles using traction and brake control

Vehicle longitudinal control is an essential part of advanced vehicle control systems. The paper is concerned with robust longitudinal velocity tracking of vehicles using traction control and brake control. First, a longitudinal vehicle model is introduced both for traction and braking modes. Then, for each mode, a robust velocity tracking controller is designed based on backstepping. At each step of constructing a candidate Lyapunov function, a scaling parameter is introduced for each added term to take into account badly scaled system states. The concepts of effective traction mass and effective braking mass are introduced in the vehicle longitudinal model such that the derived model is applicable to any types of traction and braking configuration of the vehicles. The designed controller is proved to be effective by simulation.