Vehicle Navigation Error Modeling Method And Fliting Based On FOG

With the requirements of the modern warfare to the rapid and mobility of weapon equipment, land vehicles are often required to navigate autonomously and accurately. In this paper, the error factors, which affecting the accuracy of the navigation system, are analyzed from the point of view of system and inertial device. Based on vehicle vibration environment, designed a filtering method that can meet the navigation requirements of navigation system.Firstly, the strapdown inertial navigation system(SINS) working principle and system structure are described. The attitude, position and error update algorithm and the error equation of navigation parameter are deduced in detail. The vehicle vibration model is established, the effect of vehicle vibration on the accuracy of the navigation parameters is verified by MATLAB simulation.Secondly, the main error sources of inertial navigation system and inertial device are analyzed. The performance of fiber optic gyro(FOG) is measured by ALLAN analysis of variance and power spectrum. Using the methods to analysis the output signal of the FOG, comprehensive. The measures to reduce the errors are proposed.Thirdly, under vehicle vibration environment, the error of the attitude, the position and the speed signal of the inertial navigation system are filtering noise-elimination. The mathematical model of the wavelet filtering method is derived. Combined with MALLT algorithm and multi- scale-wavelet decomposition, the effects of filtering by using the different threshold selection methods, the different wavelet bases and the different wavelet decomposition levels are discussed and summarized, The effects of different wavelet bases and different wavelet decomposition levels are discussed and summarized. It lays the foundation for the simulation verification.Finally, the flow chart of navigation solution and the filtering algorithm principle are given, and the simulation test of the algorithm is carried out by MATLAB. Under the premise of use the sine function for the effective way, the output trajectory of the inertial navigation system in ideal and real conditon are tested, including longitude, latitude and height. The error of navigation parameters such as attitude, position and velocity is analyzed. In the view of real road condition, using the wavelet filtering method to filter the navigation parameters of the inertial navigation system. Comparison the effect of the filtering in the different decomposition scales of the same wavelet basis and the different wavelet bases under the same decomposition scale, the results show that: the different wavelet bases have different filtering results, and the effect can be improved by increasing the scale of wavelet decomposition. After filtering, the accuracy of the navigation system is improved, and the navigation system can meet the actual needs.