CN103940443B - Gyroscope error calibration method - Google Patents

Abstract

The invention belongs to the technical field of inertial navigation, and particularly relates to a gyroscope error calibration method for rapidly calibrating all the error parameter values of a gyroscope by using output values of a system measurement assembly during uniform speed rotation relative to an inertial space. The method comprises that: a strapdown inertial navigation system is arranged on a position change mechanism, the three rotation shafts of the position change mechanism are respectively arranged along the right direction, the front direction and the upper direction of a carrier, aligning is performed after the system is subjected to start-up pre-heating to obtain an initial strapdown attitude matrix, the attitude angle of an IMU coordinate system relative to an inertial coordinate system at the initial time is measured, and the position change mechanism is controlled to drive the IMU to successively rotate according to the measured attitude angles, such that the IMU coordinate system coincides with the inertial coordinate system. According to the present invention, the influence of the high frequency noise in the system can be eliminated, and the IMU rotates relative to the inertial coordinate system so as to make the output signal of the gyroscope be amplified and make the interference resistance strong; and the method has characteristics of simple position change sequence, simple calculation, effective gyroscope calibration speed improvement, and effective gyroscope calibration precision increase.

Description

A kind of method that gyro error is demarcated

Technical field

The invention belongs to technical field of inertial is and in particular to a kind of utilize systematic survey assembly relative inertness space even Output valve when speed rotates, Fast Calibration goes out the method that the gyro error of all error parameter value of gyroscope is demarcated.

Background technology

With fiber optic gyro strapdown inertial navigation system（Strapdown Inertial Navigation System, SINS）The development of technology, the performance indications required precision more and more higher to device for the people, meanwhile in order to reduce the one-tenth of system This, need to take efficient system technology, carry out calibration compensation to device error, thus improving whole fiber-optic gyroscope strapdown inertial navigation System accuracy.

Calibration technique is mainly to the inertia sensitive element accelerometer of SINS and the elementary error model of fibre optic gyroscope Parameter is determined.Level according to demarcating can be divided into element to demarcate and system calibrating.Element demarcate typically before dispatching from the factory by Producer is carried out in factory, to determine the performance parameter of element.System calibrating refers to from inertial navigation system precision it is contemplated that by being used to Property element constitute the impact installing the factors such as complicated abominable of axial out of plumb and carrier movement environment during inertial navigation system, build The error mathematic model of vertical inertance element, finally realizes the process of error compensation.

The discrete scaling method generally adopting is all under geographic coordinate system, according to Inertial Measurement Unit on diverse location （Inertial Measurement Unit,IMU）Output valve between algebraic operation provide device error parameter value.This Although simple in method principle, because earth autobiography angular velocity information is small in the component of each axle of geographic coordinate system, and gyroscope Every error be in a small amount, make gyroscope sensitivity to angular velocity information faint or even covered by noise, lead to the knot demarcated Really inaccurate, and indexable relation complex calculation amount is larger.

Content of the invention

It is an object of the invention to overcoming the deficiencies in the prior art, a kind of control IMU relative inertness space of passing through is provided to revolve Turn, Gyroscope error parameter value is given to the output signal integration of gyroscope, improves the speed of system calibrating and the quick of precision The method calibrating gyro error.

The object of the present invention is achieved like this：

Step one：SINS is arranged on indexing mechanism, three rotary shafts of indexing mechanism are respectively along carrier The right side-front-upper direction, be aligned after system boot preheating, obtained initial strapdown attitude matrix

Step 2：The attitude angle of measurement initial time IMU coordinate system relative inertness coordinate system, controls indexing mechanism to drive IMU gradually rotates according to the attitude angle measured, and so that IMU coordinate system is overlapped with inertial coodinate system；

Step 3：Control indexing mechanism around the z of IMU coordinate system_sAxle is clockwise with size as ω_ieAngular velocity of rotation rotate T=60s, makes IMU coordinate system keep geo-stationary with Earth central inertial system, measures three constant value gyroscopic drift ε of system_x、ε_yWith ε_z：

${\mathrm{\ϵ}}_x=\frac{1}{T}{\∫}_0^T{\widetilde{\mathrm{\ω}}}_{\mathrm{isx}1}^s\mathrm{dt}$

${\mathrm{\ϵ}}_y=\frac{1}{T}{\∫}_0^T{\widetilde{\mathrm{\ω}}}_{\mathrm{isy}1}^s\mathrm{dt}$

${\mathrm{\ϵ}}_z=\frac{1}{T}{\∫}_0^T{\widetilde{\mathrm{\ω}}}_{\mathrm{isz}1}^s\mathrm{dt}$

In formula,It is respectively the real-time output valve of three gyroscopes；

Step 4：Control indexing mechanism around the z of IMU coordinate system_sAxle-ω with size as ω_ieAngular velocity rotate counterclockwise 360 degree, wherein ω=20 °/s, measures alignment error A_xy, alignment error A_yxWith scale factor error δ k_gz：

$A_{\mathrm{xy}}=-\frac{1}{2\mathrm{\π}}{\∫}_0^{T_z}{\widetilde{\mathrm{\ω}}}_{\mathrm{isx}2}^s\mathrm{dt}+\frac{{\mathrm{\ω\ϵ}}_x}{2\mathrm{\π}}$

$A_{\mathrm{yx}}=\frac{1}{2\mathrm{\π}}{\∫}_0^{T_z}{\widetilde{\mathrm{\ω}}}_{\mathrm{isy}2}^s\mathrm{dt}-\frac{{\mathrm{\ω\ϵ}}_y}{2\mathrm{\π}}$

${\mathrm{\δk}}_{\mathrm{gz}}=\frac{1}{2\mathrm{\π}}{\∫}_0^{T_z}{\widetilde{\mathrm{\ω}}}_{\mathrm{isz}2}^s\mathrm{dt}-\frac{{\mathrm{\ω\ϵ}}_z}{2\mathrm{\π}}$

In formula,It is respectively the real-time output valve of three gyroscopes；T_z=2 π/ω；

Step 5：Control IMU around the x of inertial coodinate system_iAxle rotates 90 degree rapidly counterclockwise；

Step 6：Control indexing mechanism around the z of IMU coordinate system_sAxle-ω with size as ω_ieAngular velocity rotate counterclockwise 360 degree, measure alignment error A_xz, alignment error A_zxWith scale factor error δ k_gy：

$A_{\mathrm{xz}}=\frac{1}{2\mathrm{\π}}{\∫}_0^{T_z}{\widetilde{\mathrm{\ω}}}_{\mathrm{isx}3}^s\mathrm{dt}-\frac{{\mathrm{\ω\ϵ}}_x}{2\mathrm{\π}}$

${\mathrm{\δk}}_{\mathrm{gy}}=\frac{1}{2\mathrm{\π}}{\∫}_0^{T_z}{\widetilde{\mathrm{\ω}}}_{\mathrm{isy}3}^s\mathrm{dt}-\frac{{\mathrm{\ω\ϵ}}_y}{2\mathrm{\π}}$

$A_{\mathrm{zx}}=-\frac{1}{2\mathrm{\π}}{\∫}_0^{T_z}{\widetilde{\mathrm{\ω}}}_{\mathrm{isz}3}^s\mathrm{dt}+\frac{{\mathrm{\ω\ϵ}}_z}{2\mathrm{\π}}$

In formula,It is respectively the real-time output valve of three gyroscopes；

Step 7：Control IMU around the y of inertial coodinate system_iAxle rotates 90 degree rapidly clockwise；

Step 8：Control indexing mechanism around the z of IMU coordinate system_sAxle-ω with size as ω_ieAngular velocity rotate counterclockwise 360 degree, measure alignment error A_xz, alignment error A_zxWith scale factor error δ k_gy：

${\mathrm{\δk}}_{\mathrm{gz}}=\frac{1}{2\mathrm{\π}}{\∫}_0^{T_z}{\widetilde{\mathrm{\ω}}}_{\mathrm{isx}4}^s\mathrm{dt}-\frac{{\mathrm{\ω\ϵ}}_x}{2\mathrm{\π}}$

$A_{\mathrm{yz}}=-\frac{1}{2\mathrm{\π}}{\∫}_0^{T_z}{\widetilde{\mathrm{\ω}}}_{\mathrm{isy}4}^s\mathrm{dt}+\frac{{\mathrm{\ω\ϵ}}_y}{2\mathrm{\π}}$

$A_{\mathrm{zy}}=\frac{1}{2\mathrm{\π}}{\∫}_0^{T_z}{\widetilde{\mathrm{\ω}}}_{\mathrm{isz}4}^s\mathrm{dt}-\frac{{\mathrm{\ω\ϵ}}_z}{2\mathrm{\π}}$

In formula,It is respectively the real-time output valve of three gyroscopes.

The beneficial effects of the present invention is：The present invention devises a kind of method that Fast Calibration goes out gyro error, the party Method can eliminate the impact of system high-frequency noises, and IMU relative inertness coordinate system rotates and so that the output signal increase of gyroscope is resisted Interference is higher, and the method indexing order simple operation is easy in addition, can effectively improve speed and the precision of gyroscope demarcation.

Brief description

Fig. 1 is calibration algorithm flow chart.

Fig. 2 is the indexable conceptual scheme demarcated.

Specific embodiment

Below in conjunction with the accompanying drawings the present invention is described further：

The principle of the present invention is：A kind of method that Fast Calibration goes out gyro error is on the basis of multiposition rotation, Overlapped with inertial coodinate system by controlling IMU coordinate system, so that three axles of IMU coordinate system regular is turned around inertial coodinate system Dynamic, take average to eliminate the impact to calibration result for the system noise output valve cycle integrated of gyroscope, then utilize gyroscope The algebraic operation Fast Calibration between output valve when each axle rotates goes out the error parameter of device.

（1）SINS is arranged on indexing mechanism, three rotary shafts of indexing mechanism respectively along carrier the right side- Before-upper direction, it is aligned after system boot preheating, obtained initial strapdown attitude matrix

（2）The attitude angle of measurement initial time IMU coordinate system relative inertness coordinate system, controls indexing mechanism to drive IMU to press Gradually rotate according to the attitude angle measured, so that IMU coordinate system is overlapped with inertial coodinate system；

（3）Control indexing mechanism around the z of IMU coordinate system_sAxle is clockwise with size as ω_ieAngular velocity of rotation rotate, make IMU coordinate system keeps geo-stationary, the now angular velocity of rotation of IMU coordinate system relative inertness coordinate system with Earth central inertial systemThe output valve of three gyroscopesWithIt is respectively：

$\left[\begin{array}{c}{\widetilde{\mathrm{\ω}}}_{\mathrm{isx}1}^s\\ {\widetilde{\mathrm{\ω}}}_{\mathrm{isy}1}^s\\ {\widetilde{\mathrm{\ω}}}_{\mathrm{isz}1}^s\end{array}\right]=\left[\begin{array}{ccc}1+{\mathrm{\δk}}_{\mathrm{gx}}& A_{\mathrm{xz}}& -A_{\mathrm{xy}}\\ -A_{\mathrm{yz}}& 1+{\mathrm{\δk}}_{\mathrm{gy}}& A_{\mathrm{yx}}\\ A_{\mathrm{zy}}& {-A}_{\mathrm{zx}}& 1+{\mathrm{\δk}}_{\mathrm{gz}}\end{array}\right]{\widehat{\mathrm{\ω}}}_{\mathrm{is}}^s+\left[\begin{array}{c}{\mathrm{\ϵ}}_x\\ {\mathrm{\ϵ}}_y\\ {\mathrm{\ϵ}}_z\end{array}\right]---\left(1\right)$

In formula, δ k_gi、A_ijAnd ε_i（I, j=x, y, z）Represent gyro scale factor error, alignment error and constant value respectively by mistake Difference.

WillBring formula into（1）In：

$\left[\begin{array}{c}{\widetilde{\mathrm{\ω}}}_{\mathrm{isx}1}^s\\ {\widetilde{\mathrm{\ω}}}_{\mathrm{isy}1}^s\\ {\widetilde{\mathrm{\ω}}}_{\mathrm{isz}1}^s\end{array}\right]=\left[\begin{array}{c}{\mathrm{\ϵ}}_x\\ {\mathrm{\ϵ}}_y\\ {\mathrm{\ϵ}}_z\end{array}\right]---\left(2\right)$

For the impact of Removing Random No, rightWithCycle integrated takes average, obtains three constant value tops Spiral shell drift ε_x、ε_yAnd ε_z：

${\mathrm{\ϵ}}_x=\frac{1}{T}{\∫}_0^T{\widetilde{\mathrm{\ω}}}_{\mathrm{isx}1}^s\mathrm{dt}$

${\mathrm{\ϵ}}_y=\frac{1}{T}{\∫}_0^T{\widetilde{\mathrm{\ω}}}_{\mathrm{isy}1}^s\mathrm{dt}---\left(3\right)$

${\mathrm{\ϵ}}_z=\frac{1}{T}{\∫}_0^T{\widetilde{\mathrm{\ω}}}_{\mathrm{isz}1}^s\mathrm{dt}$

（4）Control indexing mechanism around the z of IMU coordinate system_sAxle with size is（ω-ω_ie）Angular velocity rotate counterclockwise 360 Degree, wherein ω=20 °/s, the now angular velocity of rotation of IMU coordinate system relative inertness coordinate system ${\widehat{\mathrm{\ω}}}_{\mathrm{is}}^s{\left[\begin{array}{ccc}0& 0& \mathrm{\ω}\end{array}\right]}^T,$ According to public affairs Formula（4）Measure A_xy、A_yxWith δ k_gz：

$A_{\mathrm{xy}}=-\frac{1}{2\mathrm{\π}}{\∫}_0^{T_z}{\widetilde{\mathrm{\ω}}}_{\mathrm{isx}2}^s\mathrm{dt}+\frac{{\mathrm{\ω\ϵ}}_x}{2\mathrm{\π}}$

$A_{\mathrm{yx}}=\frac{1}{2\mathrm{\π}}{\∫}_0^{T_z}{\widetilde{\mathrm{\ω}}}_{\mathrm{isy}2}^s\mathrm{dt}-\frac{{\mathrm{\ω\ϵ}}_y}{2\mathrm{\π}}---\left(4\right)$

${\mathrm{\δk}}_{\mathrm{gz}}=\frac{1}{2\mathrm{\π}}{\∫}_0^{T_z}{\widetilde{\mathrm{\ω}}}_{\mathrm{isz}2}^s\mathrm{dt}-\frac{{\mathrm{\ω\ϵ}}_z}{2\mathrm{\π}}$

In formula,It is respectively the real-time output valve of three gyroscopes；T_z=2 π/ω.

（5）Control IMU around the x of inertial coodinate system_iAxle rotates 90 degree rapidly counterclockwise；

（6）Control indexing mechanism around the z of IMU coordinate system_sAxle with size is（ω-ω_ie）Angular velocity rotate counterclockwise 360 Degree, the now angular velocity of rotation of IMU coordinate system relative inertness coordinate system ${\widehat{\mathrm{\ω}}}_{\mathrm{is}}^s{\left[\begin{array}{ccc}0& \mathrm{\ω}& 0\end{array}\right]}^T,$ According to formula（5）Measurement A_xz、 A_zxWith δ k_gy：

$A_{\mathrm{xz}}=\frac{1}{2\mathrm{\π}}{\∫}_0^{T_z}{\widetilde{\mathrm{\ω}}}_{\mathrm{isx}}^s\mathrm{dt}-\frac{{\mathrm{\ω\ϵ}}_x}{2\mathrm{\π}}$

${\mathrm{\δk}}_{\mathrm{gy}}=\frac{1}{2\mathrm{\π}}{\∫}_0^{T_z}{\widetilde{\mathrm{\ω}}}_{\mathrm{isy}}^s\mathrm{dt}-\frac{{\mathrm{\ω\ϵ}}_y}{2\mathrm{\π}}---\left(5\right)$

$A_{\mathrm{zx}}=-\frac{1}{2\mathrm{\π}}{\∫}_0^{T_z}{\widetilde{\mathrm{\ω}}}_{\mathrm{isz}}^s\mathrm{dt}+\frac{{\mathrm{\ω\ϵ}}_z}{2\mathrm{\π}}$

（7）Control IMU around the y of inertial coodinate system_iAxle rotates 90 degree rapidly clockwise；

（8）Control indexing mechanism around the z of IMU coordinate system_sAxle with size is（ω-ω_ie）Angular velocity rotate counterclockwise 360 Degree, the now angular velocity of rotation of IMU coordinate system relative inertness coordinate system ${\widehat{\mathrm{\ω}}}_{\mathrm{is}}^s{\left[\begin{array}{ccc}\mathrm{\ω}& 0& 0\end{array}\right]}^T$ According to formula（6）Measurement A_xz、 A_zxWith δ k_gy：

${\mathrm{\δk}}_{\mathrm{gz}}=\frac{1}{2\mathrm{\π}}{\∫}_0^{T_z}{\widetilde{\mathrm{\ω}}}_{\mathrm{isx}}^s\mathrm{dt}-\frac{{\mathrm{\ω\ϵ}}_x}{2\mathrm{\π}}$

$A_{\mathrm{yz}}=-\frac{1}{2\mathrm{\π}}{\∫}_0^{T_z}{\widetilde{\mathrm{\ω}}}_{\mathrm{isy}}^s\mathrm{dt}+\frac{{\mathrm{\ω\ϵ}}_y}{2\mathrm{\π}}---\left(6\right)$

$A_{\mathrm{zy}}=\frac{1}{2\mathrm{\π}}{\∫}_0^{T_z}{\widetilde{\mathrm{\ω}}}_{\mathrm{isz}}^s\mathrm{dt}-\frac{{\mathrm{\ω\ϵ}}_z}{2\mathrm{\π}}$ .

Claims (1)

1. a kind of method that gyro error is demarcated is it is characterised in that comprise the following steps：

Step one：SINS is arranged on indexing mechanism, three rotary shafts of indexing mechanism respectively along carrier the right side- Before-upper direction, it is aligned after system boot preheating, obtained initial strapdown attitude matrix

Step 2：The attitude angle of measurement initial time IMU coordinate system relative inertness coordinate system, controls indexing mechanism to drive IMU to press Gradually rotate according to the attitude angle measured, so that IMU coordinate system is overlapped with inertial coodinate system；

Step 3：Control indexing mechanism around the z of IMU coordinate system_sAxle is clockwise with size as ω_ieAngular velocity of rotation rotate T= 60s, makes IMU coordinate system keep geo-stationary with Earth central inertial system, measures three constant value gyroscopic drift ε of system_x、ε_yAnd ε_z：

${\mathrm{\ϵ}}_x=\frac{1}{T}{\∫}_0^T{\widetilde{\mathrm{\ω}}}_{isx1}^{s}dt$

${\mathrm{\ϵ}}_y=\frac{1}{T}{\∫}_0^T{\widetilde{\mathrm{\ω}}}_{isy1}^{s}dt$

${\mathrm{\ϵ}}_z=\frac{1}{T}{\∫}_0^T{\widetilde{\mathrm{\ω}}}_{isz1}^{s}dt$

In formula,It is respectively the real-time output valve of three gyroscopes；

Step 4：Control indexing mechanism around the z of IMU coordinate system_sAxle-ω with size as ω_ieAngular velocity rotate counterclockwise 360 Degree, whereinMeasure alignment error A_xy, alignment error A_yxWith scale factor error δ k_gz：

$A_{xy}=-\frac{1}{2\mathrm{\π}}{\∫}_0^{T_z}{\widetilde{\mathrm{\ω}}}_{isx2}^{s}dt+\frac{{\mathrm{\ω\ϵ}}_x}{2\mathrm{\π}}$

$A_{yx}=\frac{1}{2\mathrm{\π}}{\∫}_0^{T_z}{\widetilde{\mathrm{\ω}}}_{isy2}^{s}dt-\frac{{\mathrm{\ω\ϵ}}_y}{2\mathrm{\π}}$

${\mathrm{\δk}}_{gz}=\frac{1}{2\mathrm{\π}}{\∫}_0^{T_z}{\widetilde{\mathrm{\ω}}}_{isz2}^{s}dt-\frac{{\mathrm{\ω\ϵ}}_z}{2\mathrm{\π}}$

In formula,It is respectively the real-time output valve of three gyroscopes；T_z=2 π/ω；

Step 5：Control IMU around the x of inertial coodinate system_iAxle rotates 90 degree rapidly counterclockwise；

Step 6：Control indexing mechanism around the z of IMU coordinate system_sAxle-ω with size as ω_ieAngular velocity rotate counterclockwise 360 Degree, measures alignment error A_xz, alignment error A_zxWith scale factor error δ k_gy：

$A_{xz}=\frac{1}{2\mathrm{\π}}{\∫}_0^{T_z}{\widetilde{\mathrm{\ω}}}_{isx3}^{s}dt-\frac{{\mathrm{\ω\ϵ}}_x}{2\mathrm{\π}}$

${\mathrm{\δk}}_{gy}=\frac{1}{2\mathrm{\π}}{\∫}_0^{T_z}{\widetilde{\mathrm{\ω}}}_{isy3}^{s}dt-\frac{{\mathrm{\ω\ϵ}}_y}{2\mathrm{\π}}$

$A_{zx}=-\frac{1}{2\mathrm{\π}}{\∫}_0^{T_z}{\widetilde{\mathrm{\ω}}}_{isz3}^{s}dt+\frac{{\mathrm{\ω\ϵ}}_z}{2\mathrm{\π}}$

In formula,It is respectively the real-time output valve of three gyroscopes；

Step 7：Control IMU around the y of inertial coodinate system_iAxle rotates 90 degree rapidly clockwise；

Step 8：Control indexing mechanism around the z of IMU coordinate system_sAxle-ω with size as ω_ieAngular velocity rotate counterclockwise 360 Degree, measures alignment error A_yz, alignment error A_zyWith scale factor error δ k_gz：

${\mathrm{\δk}}_{gz}=\frac{1}{2\mathrm{\π}}{\∫}_0^{T_z}{\widetilde{\mathrm{\ω}}}_{isx4}^{s}dt-\frac{{\mathrm{\ω\ϵ}}_x}{2\mathrm{\π}}$

$A_{yz}=-\frac{1}{2\mathrm{\π}}{\∫}_0^{T_z}{\widetilde{\mathrm{\ω}}}_{isy4}^{s}dt+\frac{{\mathrm{\ω\ϵ}}_y}{2\mathrm{\π}}$

$A_{zy}=\frac{1}{2\mathrm{\π}}{\∫}_0^{T_z}{\widetilde{\mathrm{\ω}}}_{isz4}^{s}dt-\frac{{\mathrm{\ω\ϵ}}_z}{2\mathrm{\π}}$

In formula,It is respectively the real-time output valve of three gyroscopes.