Research On Error Of Rotation Semi-Strapdown MEMS-based Inertial Navigation System

The realization of conventional ammunition guidance depends on the real-time and accurate measurement of the missile flight parameters.Limited by factors such as high rotation,high speed and narrow space,it is difficult to measure the navigation parameters such as the attitude,speed and position of the missile.The proposal of the semi-strapdown inertial navigation measurement method solves the problem of cross-range measurement,but the accuracy of the MEMS devices limits the measurement accuracy of the Semi-Strapdown Inertial Navigation System(SSINS).In order to further improve the accuracy of the system,the rotation modulation technology is introduced into the semi-strapdown system to structure a Rotary Semi-Strapdown Inertial Navigation System(RSSINS).This thesis mainly analyzes and suppresses the main errors existing in the system.Firstly,in order to facilitate the following analysis,the common coordinate system and coordinate system conversion relationship are briefly described.At the same time,the composition mechanism and working principle of the rotary semi-strap system are described.Secondly,the system error is classified and analyzed,and then the main error sources that affect the accuracy of the system are device error,modulation angular rate error,and system installation error.The propagation mechanism of each error is deduced and analyzed in detail,and the propagation characteristics of each error are obtained,and the corresponding simulations are carried out.The results are consistent with the theoretical analysis.Then,according to the evaluation criteria of the rotation scheme and the actual application requirements,a reasonable rotation scheme is selected,and the carrier motion analysis device error suppression effect is combined with the carrier motion.At the same time,combined with the modulation angular rate error and the propagation mechanism of the system installation error,the suppression method is proposed respectively.Finally,in order to verify the previous analysis,the corresponding navigation test was designed.The three-axis high-precision flight simulation turntable is used to provide a high-spinning environment.The navigation comparison test is performed before and after themodulation,and the modulated angular rate compensation and system installation error are compensated respectively to verify the effectiveness of the compensation method.The system accuracy is further improved.