Research On Attitude Detection Method Of Vehicle Navigation System Based On Single Axis Fiber Optic Gyroscope

At present,the demand for civilian unmanned vehicles is increasing,and the navigation system is one of the key systems of unmanned vehicles.The research on the navigation system is of great significance to improve the overall performance of unmanned vehicles.Because the traditional strapdown inertial navigation system is difficult to be applied to the civil market because of its high cost;Although the complete MEMS inertial navigation system is cheap,its accuracy is low,which is difficult to meet the requirements of vehicle navigation system.In order to reduce the cost of unmanned vehicle navigation system,a simple inertial navigation system based on single axis fiber optic gyroscope,RISS system,is designed in this paper.In RISS system,MEMS inclination sensor is introduced to assist in the calculation of heading information;The two antenna GPS is used to complete the initial alignment of the RISS system,and the error of the riss system is continuously corrected as the observation information in the combined system.This paper focuses on the low-cost vehicle navigation system and its attitude detection method.(1)The navigation principle of RISS system and the basic characteristics of inertial devices are analyzed.The problem of low accuracy and large noise interference of MEMS inclination sensor is studied to eliminate or reduce the noise of its output horizontal attitude angle and improve the accuracy of horizontal attitude.At the same time,the characteristics of the motion state of unmanned vehicle under different road conditions are deeply studied,and multiple.The course information solution model of RISS system and the switching rules between different models can maintain accurate course information under different road conditions and slow down the divergence of course information output by RISS system;The error equation of RISS system is deduced,which makes full theoretical preparation for the establishment of vehicle integrated navigation system model in the next step.(2)The principle of positioning and orientation of two antenna GPS and the advantages and disadvantages of satellite navigation system are analyzed.At the same time,the classification mode of integrated system is analyzed.Based on the characteristics of vehicle navigation system,the combination mode of indirect combination is selected,and the state and measurement equations of the system designed in this paper are deduced.Aiming at the influence of satellite signal quality on the error of output information of two antenna GPS,the And fiber optic gyroscope can maintain high-precision heading information in a short time.The algorithm of heading information update of integrated navigation system is deeply studied,so that the vehicle integrated navigation system can stably output accurate heading angle information for a long time.(3)The navigation information acquisition system based on STM32 is designed,and the basic parameters,setting method and sensor output data protocol used by the vehicle navigation system are analyzed.The navigation information acquisition program based on STM32 is written for the vehicle integrated navigation system,so that the vehicle navigation system designed in this paper can collect and process the navigation data output by each sensor in real time,The required navigation information is transmitted to the upper computer system through STM32 for display and storage.(4)Design and build the physical experiment platform of the vehicle navigation system and carry out the sports car experiment to test the performance of the vehicle navigation system designed in this paper,and verify the attitude detection algorithm of the vehicle navigation system proposed in this paper.According to the experimental results,the accuracy of the heading information maintained by the vehicle navigation system and algorithm designed in this paper can reach 0.3°,which can meet the needs of vehicle navigation.