An efficient control allocation algorithm for over-actuated AUVs trajectory tracking with fault-tolerant control

Fault-tolerant control of actuator faults in over-actuated autonomous underwater vehicles (AUVs) during trajectory tracking has involved problems. First, the fault-tolerant control method of controlling typical rudder faults, including lost, jammed, and/or deformed rudders, is introduced to reconstruct the control input, and a complete scheme of self-diagnosis and fault-tolerant control is proposed based on a sliding mode observer (SMO). Secondly, an efficient nonlinear saturation constraint sequential quadratic programming (SC-SQP) algorithm is proposed to solve the control allocation problem of multi-constraint quadratic programming, in particular with the motion in the initial or kinetic cycle transition stages. Considering the time-varying and unknown disturbances that occur in oceans, the control moments are compensated by the SMO to resist the perturbation of the hydrodynamic coefficient. Finally, the simulations show that the SC-SQP algorithm is efficient and can be used to solve the typical rudder faults with perturbation of the hydrodynamic coefficient during the fault-tolerant trajectory tracking control for over-actuated AUVs.