Triaxial accelerometer calibration method based on cross in inertial navigation system

Abstract

The present invention claims to protect a three-axis accelerometer calibration method based on a cross in an inertial navigation system. This method is realized by making a cross mark on a horizontal platform. The horizontal platform is any platform parallel to the ground plane. The cross is any two signs perpendicular to each other; the original value of the accelerometer is the processing object, and the original value is not divided by the value of the scale factor; the original value of the accelerometer at the six positions is filtered, and the six The position is six positions with the cross as a reference; and the filtered original value is temperature compensated by the least square method; then the average value of the temperature compensated original value is taken as the original value corresponding to the six positions; finally through the acceleration The calibration coefficient of the error calibration model can be obtained by using the formula for obtaining the calibration coefficient of the meter. The method can overcome the problems of calibration error caused by unfixed scale factor, complex calibration process, temperature drift and long calibration period.

Description

Technical field [0001] The invention belongs to a method for calibrating a three-axis accelerometer based on a cross, in particular to a method for calibrating an accelerometer in an inertial navigation system. Background technique [0002] In an inertial navigation system, the measurement accuracy of the accelerometer is affected by the installation error, zero offset and scale factor, which limits its application range. Therefore, it is necessary to calibrate the accelerometer. Calibration methods include: traditional six-position method, accelerometer calibration method based on rocket skid test, accelerometer calibration method based on Beidou second-generation velocity information, and accelerometer calibration method based on iterative calculations. The traditional six-position method is to calibrate the actual value of the accelerometer (that is, the value except for the scale factor). The principle is simple and the operation is convenient. However, in practical applicati...

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Problems solved by technology

Literature [1] proposes to calibrate the actual value of the accelerometer by the six-position method, which cannot avoid the error caused by the change of the scale factor; literature [2] uses the six-position method to calibrate the actual value of the three-axis accelerometer, which requires the use of specific three Axis turntable; literature [3] proposed an improved six-position rapid calibration method, which is also realized with the help of a turntable with and without a temperature box, which limits the use conditions of this calibration method

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