Research On Integrated Navigation Technology Of SINS/DVL Based On Underwater Vehicles

Strapdown Inertial Navigation System (SINS) have the characteristics of independence,high short-term accuracy and errors accumulating over time. Doppler Log (DVL) can provide highly accurate speed information. SINS/DVL integrated navigation system is now widely used in underwater navigation system with a high degree of autonomy and high navigation accuracy. In this paper, a integrated navigation system based on Strapdown Inertial Navigation System and Doppler Log is studied, and how to ensure positioning accuracy of integrated navigation system were discussed in depth when DVL measurement data is failure.Firstly, in this paper, the working principle of strapdown inertial navigation systems,error sources and position error equation, velocity error equation, attitude error equation are all explored in detail here. In addition, the principle of doppler velocity log, error sources and error modeling are introduced.Secondly,the Kalman filter state equation and measurement equation of integrated navigation system are established,and SINS/DVL integrated navigation system is simulated.From the simulation results, it can be seen that latitude error, longitude error and speed error of the integrated navigation system are compensated effectively after Kalman filtering and feedback correction, the system reaches a certain accuracy of navigation positioning.After, in order to improve the SINS/DVL system positioning accuracy when the DVL measurement data is invalid, it proposed the research methods which combine AUV dynamics model and adaptive neuro-fuzzy inference system (ANFIS), this method is used as the auxiliary of SINS/DVL integrated system. On one hand, AUV kinetic model can predict the speed according to the force acting there, the predicting speed is used to instead DVL to combined with SINS. On the other hand, ANFIS is continuously online training under normal working conditions already, error predicting model is established, so it can be used to forecast error in the failure DVL data situation. Simulation analysis verified the effectiveness of the proposed method, it improves the accuracy and robustness of the system.Finally, the simulation are designed to verify the accuracy and reliability of navigation systems. The results show that when the failure or malfunction of speed sensor, the auxiliary use of AUV dynamics model and ANFIS method can effectively avoid the problems of the larger navigation errors, it improved the fault tolerance and robustness of the underwater navigation system, it also meet the characteristics of high concealment and long working hours of AUV navigation system. It have a wide range of applications.