The Study Of Theory And Technique For Rocket Trajectory Correction By The Control Force Of Lateral Push Jet

On the ground,at sea and in the air,the rocket artillery plays an important role in the fire antagonism and battlefield support.It is the host equipment of army in pressing weapon. Along with the development of weapon towards to the long-range and the super-long-range, the shortage of large impact point dispersion of a rocket projectile is must be solved.In order to solve this problem,using the inexpensive control mechanism to realize the trajectory correction method is emerging as the age requirement.This thesis mainly researches on the method using the controlling force which is provided by lateral pulse jets to carry on trajectory correction of the rocket projectile,and achieves the goal that the rocket artillery can attack the target quickly and accurately.In the thesis,for the first time,on the premise of analyzing the trajectory correction scheme,the Impact Point Forecast Guidance Law(IPFGL) is proposed,with this law the trajectory correction of the rocket projectile can be realized.According to the trajectory correction scheme,the installation position and configuration parameters of the pulse jets have been determined.The simplified model of the pulse controlling forces and moments calculation has been given.The rocket projectile flight trajectory dynamic model being composed of 13 nonlinear differential equations has been established.In order to achieve the goal of low cost and anti-jamming,in this thesis,for the first time, a magnetism-inertia attitude detection system being composed of three component magnetometers and a single axle micro-machine gyroscope is proposed using on rocket projectile.On the thorough analysis to the work process of this system,the thesis has established the resolving mathematical model of rocket projectile flight attitude,and given the simulation flowchart of attitude algorithm.The simulation results indicate that the attitude resolving algorithm can satisfy the request of measuring accuracy.According to the rocket dynamic model,the trajectory correction efficiency is compared between IPFGL with Trajectory Tracking Guidance law(TT) and Parabolic Proportional Navigation Guidance Law(PAPNG) proposed by Thanat Jitpraphai,Bradley Burchett et al. The results show that IPFGL is superior to two other kinds of guidance laws for trajectory correction efficiency in longitudinal direction(the direction of fire) and crosswise direction. For the first time,the thesis put forward the method of getting impact point error by establishing the target coordinate system.Taking the 122mm 30km rocket projectile as the simulation computation model,a single trajectory average calculating time is 2 seconds by use of four steps Runge-Kutta algorithm,it can't satisfy the rapidity request of the trajectory correction system.Therefore,a reasonable linear projectile theory is proposed. Simulation results show that a single trajectory resolving time can be reduced by 1 times under the calculation error being less than 0.1%.The concept of single pulse jet correction ability function(ABI) is proposed for the first time in thesis,ABI = F(X,F_j).Here,X is the distance between the rocket projectile mass center with the target point,F_j is the control force.According to ABI and the simulation experiment,the correction ability decision table has been obtained,and finally the best configuration parameters of the pulse jet have been given.In summary,the theoretical analysis and the simulation experiment indicated that the method bring forward by the thesis,which use the controlling force provided by the pulse jet to realize the rocket projectile trajectory correction,has certain practical value.