Research On Systematic Calibration Of All Parameters Of Strapdown Inertial Navigation

Inertial navigation is a closed autonomous navigation m ethod, which also provides the carrier’s velocity and attitude information at the same time. Inertial navigation system does not depend on external information, is free from external electromagnetic interference, environmental and climatic constraints and provides continuous navigation information. With the rapid development of computer technology, relying on the posture matrix which simulates geographic coordinate system solved by computer, SINS are widely used in the aerospace vehicle, marine, weapons and equipment with its advantages of light weight, easy maintenance and so on, gradually replaced the old INS. But SINS still exist initial error parameter calibration problem like Inertial Navigation System in use. The error of Inertial Measurement Unit is the main source error element of inertial navigation, so the calibration accuracy of inertial measurement unit error will directly affect the accuracy of navigation system.Firstly, this paper gives a inertial measurement error model, and then analyzes the error’s propagation characteristics in SINS, meanwhile, analyzes the various inertial navigation system error affected by measurement error. Then introduces the main theoretical basis of Empirical Mode Decomposition,and gives the physical meaning of the relevant parameters of variables and functions.This paper presents a calibration method based on empirical mode decomposition, Firstly, the design process verifies the accuracy of empirical mode decomposition and the feasibility for amplitude modulating signal decomposition; Secondly, the mathematical basis of the theory of calibration method is given, and discusses the identifiability of each error, then, analysis the problem of the navigation parameters using empirical mode decomposition and provides a solution. Finally this paper simulates calibration accuracy of empirical mode decomposition. This approach compared to the traditional twenty-four stationary position calibration method reduces the number of positions, compared to the six position calibration method does not need repeated rotation, compared to the three-position calibration method can provide 24 full y parametric calibration results.