This paper investigates a prescribed tracking performance vehicular platoon control problem with actuator saturation, dynamics uncertainties, and unknown disturbances. First, a novel Gaussian error function (GEF)-based saturation function is introduced to approximate nonsmooth actuator saturation of each vehicle in a smooth way. Then, a fixed-time performance function (FPF) is proposed. Subsequently, an adaptive fixed-time sliding mode control scheme is developed based on the GEF and the FPF, which guarantees all signals of the closed-loop system are bounded and the tracking error converges to a predetermined region in fixed time. Meanwhile, string stability and traffic stability are also guaranteed. Finally, the effectiveness of the proposed algorithm is verified through numerical simulations.

This paper investigates a fixed-time leader-following formation control method for a set of autonomous underwater vehicles (AUVs) with event-triggered acoustic communications. First, an eventtriggering communication strategy is developed to govern the communications between leader AUV and follower AUVs. Then, using fixed-time control theory and Lyapunov functional method, a compensator based command filtered formation control algorithm is proposed, with which the follower AUVs can track the leader AUV in a given fixed time. Namely, the control method can guarantee all the signals in the formation control system to be globally fixed-time stabilized.With the presented fixed-time control scheme, the predesignated AUVs formation can be achieved within a fixed settling time under arbitrary initial system states, which is otherwise impossible under any existing methods including finite-time control. Furthermore, the compensator based command filtered control technique makes the designed formation control law simple and easy to implement in practice. Simulation results demonstrate the effectiveness of the method.

This paper investigates the prescribed performance control problem for a vehicular platoon (i.e., a group of vehicles that travels in close proximity to one another, nose-to-tail, at highway speeds) simultaneously considering actuator faults and saturation. In the first case, a Gaussian error function (GEF) is applied to replace the nonsmooth actuator saturation of each vehicle in a smooth way. Then, a finite-time prescribed performance function (FNPPF) is proposed, which guarantees the tracking error of the platoon system converges to a predetermined region in a defined time. Subsequently, by combing the fuzzy-logic system (FLS) and parameter learning algorithm, an adaptive control scheme is developed in the context of sliding mode control, which guarantees all signals in the closed-loop system are practically finite-time stable. Finally, numerical simulations are carried out for a six-vehicle platoon to show the effectiveness of the proposed algorithm.

This brief focuses on the problem of prescribed-time platoon control for vehicles with external disturbances. First, a novel disturbance observer is developed, which can accurately estimate the disturbance with zero estimation error within a specified time. Then, a prescribed-time control scheme is proposed, by employing the disturbance observer and sliding mode control method. It is proved that the given control scheme can not only ensure the tracking errors converge to the origin in the prescribed time, but also the settling time can be preassigned by assigning a simple parameter within physically allowable range. Meanwhile, the prescribed-time string stability of the platoon is also guaranteed. Finally, the effectiveness of the proposed control scheme is illustrated by numerical simulations.