The Research Of Initial Alignment And Calibration Of Laser Strapdown Inertial Navigation System

With the laser gyro strapdown inertial navigation system (LSINS) technology is being applied more and more widely, the initial alignment and calibration method of the system have aroused people's attention, the systematic calibration method of LSINS is carried out by this paper. The main research contents and results are as follows:Firstly, for the initial alignment of LSINS on the stationary base, the principle of analytical coarse alignment and the fine alignment base on Kalman filter is discussed, then the set of state equations and measurement equations of the filter are established, and the initial alignment algorithm programs are proven to be correct by the initial alignment experiment.Secondly, the error model of the LSINS is derived for the separated calibration technology. And the designed velocity experiment and position experiment are completed on the three-axis turntable of the laboratory.Thirdly, the Kalman filter which contains thirty state variables is designed based on the LSINS systematic calibration, and the set of state equations and measurement equations of the filter are established, then the systematic calibration experiment is conducted according to the design of turn sequence. Finally, the results of the two calibration methods are compared.A high precision estimation method of the error parameters of the LSINS is provided by this paper, which has important application value for improving the performance of the inertial navigation system.