Research On Propulsive System Fault Diagnosis And Fault Tolerance Of AUV

The research on fault diagnosis and fault tolerance is a pop field of Autonomous Underwater Vehicle (AUV) technology. The capability of self-diagnosis and tolerance is an important factor of AUV intelligence, meanwhile, it is powerful to guarantee AUV to accomplish missions and assignment. The main work of this paper is propulsive system fault diagnosis and fault tolerance of AUV. Here, the propulsive system includes main thrusters,assistant thrusters and rudders. The precondition of propulsive system fault diagnosis is data credibility of sensors, thus, the sensor fault diagnosis signal recover is researched first.In order to resolve problems as limited fault data,strong stochastic and real time requesting in sensor fault diagnosis of AUV, the paper introduces buildup model principle of the grey dynamic predictive model and using it in the sensor fault diagnosis of the AUV. After grey modeling with little swatch and grey dynamic prediction, this method can realize real time sensor fault diagnosis of AUV. Simulation is researched in allusion to four kinds of familiar sensor fault modes of AUV. More, a method of multi-sensor information for AUV is used to diagnose sensor fault and signal recover. The predictive data of fault sensor and multi-sensor data which are not fault is fused to realize signal recover.Strong Tracking Filter (STF) for AUV propulsive system fault diagnosis and fault tolerance is used to overcome the negative affects of the nonlinearities and uncertainties of AUV motion. The STFs are respectively established based on natural mode and each fault mode of AUV. Based on the principle of model matching and analyzing the diagnostic residuals between estimate of STF and AUV real state, the fault diagnosis is realized. As an instance, the simulation is researched on horizontal motion of AUV. At last, the paper discusses the fault tolerance method of AUV when the propulsive system is in fault. Hardware and function redundancy of AUV system is analysed. In allusion to each fault mode of any execute- machine, the fault tolerance methods are respectively discussed.