Predefined-Time Fault-Tolerant Trajectory Tracking Control for Autonomous Underwater Vehicles Considering Actuator Saturation

This paper presents the design of two predefined-time active fault-tolerant controllers for trajectory tracking autonomous underwater vehicles (AUVs) which can address actuator faults without causing saturation. The first controller offers improved steady-state precision, while second ensures a nonsingular property. Firstly, sliding mode is formulated based on disturbance observer by integrating novel auxiliary system to prevent control input from exceeding actuator’s physical limitations. Subsequently, non-singular backstepping introduced circumvent potential singularities in controller, guaranteeing that error uniformly ultimately bounded (UUB) within predefined time. Additionally, theoretical analysis and simulation results are presented illustrate advantages proposed method.