Nonlinear Disturbance Observer-Based Fault-Tolerant Sliding-Mode Control for 2-D Plane Vehicular Platoon With UTVFD and ANAS.

This article investigates a nonlinear disturbance observer (NDO)-based fault-tolerant sliding-mode control (SMC) for 2-D plane vehicular platoon systems subjected to actuator faults with unknown time-varying fault direction (UTVFD), asymmetric nonlinear actuator saturation (ANAS), nonlinear unmodeled dynamics, and unknown external disturbance. The Nussbaum-type function approach is adopted to solve the problem of actuator faults with UTVFD. The designed NDO not only can estimate the lumped disturbance accurately but also can reduce the control peaking and chattering phenomena caused by the Nussbaum-type function. Then, an adaptive saturation compensator is designed to compensate for the influence of actuator saturation on the system. In addition, by combining SMC technology with the prescribed tracking performance (PTP) approach, a distributed fault-tolerant control scheme is developed to not only ensure collision avoidance and communication connectivity but also realize a variety of driving scenarios, such as multilane vehicle merging and vehicular platoon lane changing. Finally, simulation results are presented to show the proposed scheme's effectiveness and advantages.

Fully Distributed Adaptive Fault-Tolerant Sliding-Mode Control for Nonlinear Leader-Following Multiagent Systems With ANASs and IQCs.

In this article, by combining the skills of the pseudo-PID sliding-mode control (SMC) method with adaptive control techniques, two novel fully distributed adaptive fault-tolerant control strategies are proposed to handle the leader-following consensus problem of nonlinear multiagent systems with integral quadratic constraints (IQCs) and actuator faults, with and without asymmetric nonlinear actuator saturations (ANASs). For the no-saturation case, the designed controller has a simple structure and low computation but requires the crude information of the system model. To overcome this weakness, for the saturation case, the controller is redesigned by introducing a novel anti-windup compensator and fuzzy-logic systems (FLSs), where the problem of reducing computational complexity is also considered. The controllers only need local neighbor information instead of global topology information and ensure the practical consensus of the leader-following systems in finite time. Finally, simulation results demonstrate the effectiveness of the proposed approaches.