Study On Accuracy Evaluation And Trajectory Conversion Of Inertial-stellar Integrated Guidance System Based On Multiple Warheads

It is the main development direction for multiple independently targeted reentry vehicle's ballistic missile.Accuracy evaluation and trajectory conversion methods of inertial–stellar integrated guidance are the key issues of missile weapon test.In this paper,the error propagation models are established,the accuracy of inertial guidance method or inertial-stellar integrated guidance method is analyzed,the tow identification methods for guidance instruments error are proposed,the tow conversion and evaluation methods of missile impact point deviation of the whole trajectory are given.The advantages and disadvantages of the ballistic conversion methods are compared and analyzed through digital simulation experiments.First,the error models mainly include initial collimation error and guidance instrumentation error in the process of establishing the error model.The relationships between various errors and platform misalignment angle or various errors and the differences of velocity and position between tracking and telemetry or various errors and the measured data of the star sensor or various errors and missile impact point deviation are analyzed.The calculation and correctness verification method of the environmental function matrix are given.Secondly,based on the development trend of the current strategic ballistic missiles,the characteristics of inertial guidance method and inertial–stellar integrated guidance are analyzed reasonably and the inertial–stellar integrated guidance of single satellite is affirmed.Then,the advantages and disadvantages of traditional error identification methods and modern intelligent algorithms are discussed by referring to the previous experience of the identification methods for inertial guidance error.The least square method of equal weight normalization and genetic algorithm are used to identify error coefficients respectively.Finally,the numerical simulation test is proposed.The conversion of the ballistic drop point deviation and the accuracy evaluation of the whole process are converted through the identification results of error coefficients based on the above two methods.The simulation results show that the identification accuracy of the equal weight normalized least squares method is higher than that of the genetic algorithm,and the multi-source observation data information types are fitted better.Based on the numerical simulation test,the error coefficient identification results obtained by the equal weight normalized least squares method have smaller error,the error of missile impact point deviation is close to zero,smaller standard deviation when converted to the whole process.And accuracy evaluation is more accurate.Analytical method and Monte Carlo simulation method are used to analyze the conversion accuracy of missile impact point deviation of the equivalent weight normalized least squares method.The conversion's standard deviation of the two methods is close.To a certain extent,the correctness of the method and the accuracy of conversion are verified.The research results of this paper will promote the development of precision analysis and evaluation technology of new type ballistic missile weapon system in China.