Research On The Technology Of Trajectory Filter And Falling Point Estimation For Guided Ammunition

To attack the enemy accurately,using a small amount of ammunition achieves the desired combat effect as much as possible.The low cost simple trajectory projectile became the first choice and the focus of research direction in each country because of its high ratio of expense and impact.At the time of ballistic correction,it needs to process the measured data of part of ballistic trajectory to accurately predict the trajectory falling point.By comparing predicted falling point with the information of target,the deviation from the falling point is obtained as the deviation from the trajectory,and the correction instruction is formed.Therefore,According to filtering the measured data to improve the precision of predicted falling point,it is the key technology of the intelligence of trajectory correction ammunition.In this paper,the Kalman filter is used to deal with the part of trajectory data based on the satellite navigation,removes stochastic noises then provides high accuracy data for calculating the deviation from the trajectory.This paper introduces the commonly used methods of exterior ballistic measurement,the composition of satellite navigation system and the measurement program based on the satellite navigation.The factors that influence the accuracy of the extrapolation falling point are analyzed,such as meteorological data processing,extrapolation error,ballistic parameter error and measurement error.Considering the filter accuracy and complexity of algorithms,the ballistic model of filtering and the ballistic model of extrapolating are established by using particle trajectory equations,extended Kalman filter method and unscented Kalman filter method in this paper.On the basis of simulation data of the BeiDou Navigation Satellite system,this paper uses orthogonal polynomial fitting method to estimate the initial value of filter,takes the terminal data which is fitted and the measured data at the same time as the initial value of filter,and uses two methods to make the simulation.The results show that the convergence speed of the former is 18%~50% higher than that of the latter,The maximum value of ballistic parameter estimation error is 39% and 25% of the measurement error when the satellite receiver is working normally,and that the ballistic model of extended Kalman filter,theballistic model of unscented Kalman filter and the ballistic model of extrapolating have higher accuracy.