Adaptive Fault-Tolerant Control of Fixed-wing UAV Under Actuator Saturation and State Constraints

Abstract

This paper proposes a fault-tolerant control (FTC) scheme for unmanned aerial vehicles (UAVs) with state constraints, actuator saturation, and faults. Firstly, a nonlinear mapping function is designed to transform the limited states into new unlimited states. Furthermore, based on the transformed system, neural network (NN) is used to approximate the unknown nonlinear function caused by the parametric uncertainties, external disturbances, and actuator faults. Then, dynamic surface control (DSC) technique is used to solve the problem of “explosion of complexity”. Moreover, an auxiliary system is designed to avoid actuator saturation and a Nussbaum function is used to simplify solving the inverse of the matrix in the auxiliary system. Finally, the Lyapunov method is used to prove the correctness of the FTC scheme, and simulation results show the effectiveness of this scheme.