NESO-Based Cooperative Tracking Control with Time Headway Policy and Guaranteed Performance for V2V-Enabled Vehicular Platoon

The selection of spacing policy and spacing error precision directly affect the safety of connected vehicles under the uncertain initial conditions. In this paper, the variable time headway policy is utilized for vehicular platoon systems, which possesses higher flexibility of vehicles in practical environments. Simultaneously, to address the inevitable uncertain initial spacing from adjacent vehicles, a shift function and barrier Lyapunov functions are established, where the spacing error and virtual errors can converge to predefined asymmetric performance boundaries within settling time. With the support of nonlinear extended state observer (NESO), external disturbances of corresponding channel are estimated. Additionally, the observation performance is improved by modifying the non-smoothness of nonlinear function for NESO. By employing Lyapunov stability theory, all signals of the systems are semi-global uniformly ultimately bounded, and the internal stability and string stability are guaranteed. The simulation experiments are conducted to verify the feasibility and robustness of the proposed scheme.