Fault tolerant control for an autonomous underwater vehicle to dock with thruster redundancy

This paper investigates the fault tolerant control (FTC) for an autonomous underwater vehicle (AUV) with thruster redundancy while the AUV is commanded to dock into a station. A Dubins curve is predefined as an optimal docking path for the AUV to follow and a group of azimuth thrusters are equipped on the AUV to deal with the uncertain faults and failures occurred on the rudders and thrusters. Based on the vehicle kinematics and dynamics, a path-following controller with the optimized FTC input generated from the Quadratic Programming (QP) process is adopted to carry out the docking mission while any fault or failure occurs. Simulation of an AUV with four azimuth thrusters to dock shows that the FTC induces satisfactory docking result while faults occur on the rudders and thrusters.