Safety-Critical Control of Quadrotor UAV System Considering Actuator Faults and Output Constraints

Safe and reliable control provides a critical guarantee for the stable operation of quadrotor unmanned aerial vehicles (UAVs) in low-altitude scenarios. This article proposed a safety-critical control strategy for a quadrotor UAV through the integration of output constrained tracking and fault-tolerant mechanisms. First, a barrier Lyapunov function is incorporated into a backstepping control framework to rigorously enforce time-varying output constraints. Subsequently, a composite estimation module comprised of a disturbance observer and radial basis function neural networks is constructed to jointly compensate the influence of external disturbances and actuator faults. Furthermore, to address the noise amplification problem, a command filter is employed to derive a virtual control law of the proposed system, while an auxiliary system is designed to alleviate the impact of filter error. Besides, semi-globally bounded stability is proved by the Lyapunov direct method. Finally, the proposed safe and reliable control scheme is implemented on a quadrotor platform, where its effectiveness is verified by both simulations and experiments.