A fault tolerant tracking control for a quadrotor UAV subject to simultaneous actuator faults and exogenous disturbances

• Published in: International journal of control Vol. 93; no. 3; pp. 655 - 668
• Main Authors: Mallavalli, Seema, Fekih, Afef
• Format: Journal Article
• Language: English
• Published: Abingdon Taylor & Francis 03.03.2020; Taylor & Francis Ltd
• Subjects: actuator faults; Actuators; Adaptive control; Disturbances; Fault tolerance; Fault tolerant control; Faults; Fuzzy logic; fuzzy observer; Fuzzy systems; integral terminal sliding mode control (ITSMC); Robust control; robustness; Saturation; Sliding mode control; Stability analysis; State observers; Tracking control; Unmanned aerial vehicles; Unmanned helicopters
• DOI: 10.1080/00207179.2018.1484173
• ISSN: 0020-7179

An observer-based robust adaptive Fault Tolerant Control approach is proposed in this paper to tackle the problem of trajectory tracking for a quadrotor unmanned aerial vehicle (UAV) suffering simultaneous actuator faults, exogenous disturbances and actuator saturation limits. An adaptive fuzzy state observer is proposed to estimate the immeasurable states by using fuzzy logic systems to approximate the unknown nonlinear functions of the uncertain system model. Based on the estimates of the fuzzy observer, an Integral Terminal Sliding Mode Controller that guarantees finite time convergence of the states to a small neighbourhood of zero, even under impaired conditions, is developed. Stability analysis was carried over using the Lyapunov method. The proposed approach was implemented to a quadrotor UAV and its performance was assessed under nominal conditions, and by subjecting the quadrotor to disturbances, simultaneously occurring actuator faults and input saturation limits. Excellent tracking performance and robustness even under worst-case scenarios are among the positive features of the proposed approach.