Approach to Reconfiguration of a Motion Control System for an Autonomous Underwater Vehicle

Abstract

Reconfiguration of a motion control system (MCS) for an autonomous underwater vehicle (AUV) in case of failure of some of the controls or actuators that provide the vehicle propulsion and maneuvering is discussed. The features of actuators operating on different physical principles are analyzed. A nonlinear mathematical model of the vehicle motion is formed taking into account the features of the seawater medium due to higher viscosity. Nonlinearity does not allow traditional approaches to reconfiguration of aircraft motion control system to be used for the purposes described in this paper. The approach proposed for reconfiguration of the AUV MCS consists in the preliminary analysis of the conditions for using different kinds of actuators depending on the vehicle speed and maneuver. The choice of alternative efficient actuators is dictated by the need to compensate for the forces and moments generated by the failed equipment or the actuator to the maximum extent possible. The results of the AUV MCS reconfiguration are obtained for a failure of a bow rudders gear during the diving maneuver on the acceleration section of the path. Vertical thrusters are taken as backups capable of compensating for the forces and moments of the jammed bow rudders gear. The comparative quantitative estimates of the AUV MCS reconfiguration were obtained by mathematical simulation of the AUV diving maneuver. Further research is needed to extend the proposed approach to other AUV systems.