Inertial measurement unit alignment method

Abstract

The invention discloses an inertial measurement unit alignment method. The method comprises the following steps: acquiring output data of an inertial device in a shaking environment; decomposing an attitude matrix based on an inertial solidification principle; solving an attitude matrix based on a dual-vector attitude determination TRIAD algorithm and a recursive quaternion estimation REQUEST algorithm, and obtaining a coarse alignment result; establishing a Kalman filtering error model by taking a coarse alignment result obtained in the coarse alignment stage as an initial value, and carrying out iterative filtering alignment by applying inertial device data stored at past moments to obtain an initial alignment result; and outputting an initial alignment result in the shaking environment. The problem that a traditional coarse alignment method is not high in alignment precision under the condition of large-amplitude shaking interference in the prior art can be solved. According to the initial alignment result of the vehicle-mounted positioning and orientation system under the shaking base, the method can effectively adapt to a strong shaking interference environment, and the optimal alignment precision is realized while the alignment time is shortened.

Description

technical field [0001] The invention belongs to the technical field of inertial navigation, and relates to an alignment method of an inertial measurement unit. Background technique [0002] As an important branch of the inertial navigation field, the vehicle positioning and orientation system has opened up broad application prospects in strategic military and commercial civilian fields, and plays an important role in national defense construction and national economic development. In the vehicle positioning and orientation system, the inertial navigation technology is the process of integrating the attitude, velocity and position of the carrier based on the measurement information of the inertial sensor. As the core link of the inertial navigation technology, the task of initial alignment is to determine the attitude matrix of the carrier. The operation provides an accurate initial value of the integral. In order to ensure the mobility of the carrier, the vehicle positionin...

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