Observer-Based Adaptive Prescribed Performance Control for Vehicular Platoons With Actuator Faults and Mixed Dead Zone--Saturation Constraints

In this article, a fixed-time prescribed performance control (PPC) scheme is proposed for vehicular platoons with uncertain dynamics and actuator faults, dead zones, and saturation. A novel sigmoid function is employed to smoothly approximate asymmetric actuator saturation and dead zones, and a unified framework is constructed that can simultaneously account for actuator faults. To handle model uncertainties and external disturbances, an observer is designed to estimate disturbances within a prescribed time. The proposed scheme uses adaptive sliding-mode control to ensure that tracking errors converge to prescribed steady-state regions within a fixed time to achieve the fixed-time individual vehicle stability and string stability without considering initial errors between vehicles. Simulation experiments are performed to verify the effectiveness of the proposed scheme.