Actuator Fault Detection for Automation Underwater Vehicle via Extended State Observer and Adaptive Threshold

This paper addresses the propeller and rudder fault detection problems of automation underwater vehicle (AUV) since the actuator reliability is of great significance to the system security. Based on the six degree of freedom model of underwater vehicle, an extended state observer (ESO) and adaptive threshold based fault detection scheme is proposed in this paper. Firstly, the expanded state variables are used to obtain the diagnosis residuals between actual and estimated outputs. Further, an improved adaptive threshold is designed to monitor the change of residuals aiming at reducing the fault missing alarms. The simulation results show that the proposed scheme has an outstanding detection sensitivity for AUV actuators.