Dynamic Output Feedback Fault Tolerant Control for Unmanned Underwater Vehicles

• Published in: IEEE transactions on vehicular technology Vol. 69; no. 4; pp. 3693 - 3702
• Main Authors: Wang, Xianghua, Tan, Chee Pin
• Format: Journal Article
• Language: English
• Published: New York IEEE 01.04.2020; The Institute of Electrical and Electronics Engineers, Inc. (IEEE)
• Subjects: actuator fault; Actuators; Adaptive learning; Adaptive systems; Angular velocity; Autonomous underwater vehicles; Computer simulation; Control systems; Disturbances; Dynamic output feedback fault tolerant control; Dynamics; Fault tolerance; Observers; Output feedback; Saturation; Tracking errors; Trajectories; Trajectory tracking; Uncertainty; unmanned underwater vehicle; Vehicle dynamics
• ISSN: 0018-9545; 1939-9359
• DOI: 10.1109/TVT.2019.2957529

In this paper, we propose a dynamic output feedback fault tolerant control (FTC) scheme to achieve trajectory tracking for an unmanned underwater vehicle (UUV) subject to actuator faults, actuator saturation, external disturbances and other system uncertainties. To make matters more challenging, it is assumed that the velocities (linear and angular) are unavailable. In this condition, the UUV motion model in the horizontal plane has a high relative degree, thus increasing the design complexity. In contrast to observer-based FTC schemes, we introduce a dynamic compensator, which produces an augmented error system whose dynamics is minimum phase and relative degree one. An adaptive learning observer is then introduced to address the composite uncertainties arising from actuator faults, uncertain nonlinearities, actuator saturation and disturbances. We show that the proposed scheme can ensure that the trajectory tracking errors converge to a small neighbourhood around zero. Finally, a simulation example is used to prove the efficacy of the proposed scheme.