Finite-Time Observer-Based Path-Following Control of an Underactuated Surface Vehicle with Actuator Saturation and Fault

In this paper, a finite-time observer-based fault-tolerant control (F-FTC) scheme is proposed to address path following problem of an underactuated surface vehicle suffering from input saturation and actuator gain degradation. First, a finite-time observer is designed to accurately detect faults and complex system uncertainties within the faulty system. Second, a smooth dead-zone operator-based model is applied to avoid the potential non-differentiability in controller. Finally, the F-FTC is established by virtue of a first-order filtering system. Lyapunov theory is used to verify the closed-loop system stability while simulations experiments validate the merits of the proposed F-FTC scheme.