Study Of The Attitude Angles Determination Of Trajectory Correction Projectile Based On Geomagnetism Detection And The Correction Method For Its Trajectory

The autonomous attitude angles determination technology based on geomagnetic detection and the trajectory correction method for trajectory correction projectile are researched with the application background of attitude angles detection for a Trajectory Correction Projectile(TCP).Based on the theory of geomagnetism,combined with the data gained from geomagnetic software,,after analyzing the geomagnetic field of our nation in quantity,it is confirmed that the attitude angles algorithm for projectile can be realized based on geomagnetic field measurement.The properties of various magnetic sensors including analog and digital sensors are systematically summarized,their advantage and shortage are compared and a geomagnetic detection system with high resolution is designed.The algorithm of attitude angles of TCP is researched.It is pointed out that the full attitude angles can't be calculated out only with geomagnetic detection but can be solved with different methods in two situations that the yaw of projectile is known and not known, so the solving expressions are brought out and its inaccuracy with the influence of oscillating of projectile are analyzed.Based on the above analysis,the optimum control measure for two dimension trajectory correction only with geomagnetic detection is brought out.Based on the model of ballistic of 6 degree of freedom the simulation experiments are designed by Uniform Design method.A model among correction ability of distance and angle for projectile with various initial velocity and firing angle by correction impulse with different correction delay time and class number of engine and its firing angle is obtained from the regression analysis,and the affection to the correction ability by the five elements is analized.Three measures to control the Electromagnetic Compatibility(EMC) of attitude determination system are brought out.The affection of geomagnetic signal with different material and structure of the projectile body is analyzed,the magnetic shielding effectiveness of projectile body is calculated by approximate method and proved by the numerical simulation with finite element software of ANSYS.The set system of initial information is designed.The simple 3 dimension geomagnetic acquisition system with high precision is designed to meet the need of signal acquisition for TCP.The experiment of bias voltage of electric bridge is carried out.The method of calibration for attitude angle based on 3 axle rotary platform is brought out.The circuit board for roll angle determination is used to test and the result shows that its precision is satisfiable and can meet the need of attitude determination for TCP.