On fault-tolerant control of a hovering AUV with four horizontal and two vertical thrusters

This paper discusses fault-tolerant control of a hovering AUV with four horizontal and two vertical thrusters. Three thruster fault cases are considered: the first one is when any one of the four horizontal thrusters is faulty; the second is when any two of the four horizontal thrusters are faulty; and the third is when any two of the four horizontal thrusters and any one of the two vertical thrusters are faulty. Through a series of simulations, it is shown that the AUV can track a planned path on a horizontal plane with minimally three thrusters (two are horizontal ones); however, some cases require sideways motion, cruising AUV-like motion, and oblique motion. Additionally, we briefly introduce our AUV simulator that can run hardware-in-the-loop simulation.