CN104897178A - Dual-inertial navigation combination spin modulation navigation and online relative performance assessment method - Google Patents

Abstract

The invention discloses a dual-inertial navigation combination spin modulation navigation and online relative performance assessment method for solving the problem of difficulty in assessing inertial navigation performance. By the steps of coordinate system defining, combination spin modulation strategy arrangement, combination system state equation determination, measurement equation determination and Kalman filtering, online assessment of the inertial navigation performance is realized, and an information fusion effect among multiple inertial navigation systems is improved. The assessment method can be used for assessment of the inertial navigation system relative performance under long-endurance and high-precision navigation conditions and inertial navigation system fault diagnosis, and has positive significance to ensuring navigation precision under the long-endurance condition.

Description

The navigation of a kind of two inertial navigation associating rotation modulation and online relative performance appraisal procedure

Technical field

The present invention relates to a kind of inertial navigation performance online appraisal procedure, particularly the navigation of a kind of two inertial navigation associating rotation modulation and online relative performance appraisal procedure.

Background technology

The Inertial Measurement Unit (IMU) of inertial navigation system by gyro, add table and form, gyro, the precision adding table determine the performance of inertial navigation system, and inertial navigation performance determines the precision of navigation.Inertial navigation system all needed to carry out performance test before being configured to embody rule environment, at present, generally taked two class testings both at home and abroad to the test of inertial navigation performance:

1, device level test.Mainly to gyro, add table and carry out single device detection, the device high by test screen precision forms Inertial Measurement Unit, to meet the application of some high precision navigational environment.

2, system level testing.Mainly before inertial navigation system is formally applied, system level testing is carried out to Inertial Measurement Unit, it is generally the pure inertial navigation precision investigating inertial navigation system in a static condition, in addition, according to the difference of inertial navigation applied environment, also need to carry out the system accuracy test under other conditions.

This two class testing is all carry out off-line test before inertial navigation system is formally applied, off-line test Problems existing is: even if off-line test inertial navigation precision is up to standard, but due to gyro when inertial navigation works long hours, add zero of table and partially there will be change, directly can affect navigation accuracy, inertial navigation fault can be there is in addition, cause navigational error.Under the condition not relying on extraneous reference information, how to the gyro of change, add table zero and partially estimate, and then to carry out the assessment of system-level performance online be the problem needing to solve, in existing achievement in research, not by under the condition of oracle, online evaluation cannot be carried out to inertial navigation performance.

For ensureing reliability, boat-carrying inertial navigation system is redundant configuration (general carry two cover) often, other inertial navigation systems needing high precision to navigate also often redundant configuration.Working method is master-slave back-up mode, and only have a set of inertial navigation in running order, other system is in Status of Backups, and consider from Information Pull angle, master-slave back-up working method causes the wasting of resources indirectly.How to fully utilize the information of redundant configuration inertial navigation system, and then realize carrying out online evaluation to inertial navigation performance, it is the problem needing to solve that the navigational parameter of the system that preferred precision is high exports as system, has no open report both at home and abroad.

" a kind of two inertial navigation combination navigation method " in CNKI storehouse (Liu Weiren, Wang Ning, Liu Guobin, year great waves, Ai Guangbin; China's inertial technology journal; Phase February the 1st in 2014) literary composition disclose a kind of utilize fixing refer to northern inertial navigation system, stage body orientation rotation inertial navigation system carries out the method that information fusion improves navigation accuracy, but do not relate to the navigation of proposed one two inertial navigation associating rotation modulation and online relative performance appraisal procedure.

Summary of the invention

The present invention is directed to the problem of inertial navigation performance online assessment, propose the navigation of a kind of two inertial navigation associating rotation modulation and online relative performance appraisal procedure, the method is by the reasonable layout to double ionertial navigation system associating rotation modulation strategy, make the transposition rule of different inertial navigation system different, thus make inertial navigation system error characteristics have certain complementarity, without under extraneous measurement information condition, choose error state, using the difference of inertial navigation system navigational parameter as measurement information, carry out Kalman filtering, to constant value or the slow gyroscopic drift changed, add table zero partially to estimate, and then the relative performance of inertial navigation system is assessed.

The technical solution taked for realizing the present invention is:

The navigation of a kind of two inertial navigation associating rotation modulation and online relative performance appraisal procedure, the steps include:

Step one: coordinate system defines, definition navigational coordinate system (n system) is local horizontal geographic coordinate system, coordinate axis points to north orientation-east orientation-ground respectively to (N-E-D), carrier coordinate system (b system) coordinate axis is respectively along the roll axle-pitch axis-yaw axis (front-right-under) of carrier, and Inertial Measurement Unit (IMU) coordinate system of inertial navigation system 1,2 is respectively s ₁, s ₂, coordinate axis is pointed to and is defined with carrier coordinate system;

Step 2: associating rotation modulation strategy layout, inertial navigation system 1,2 carries out 4 position 8 order rotation modulation transpositions around azimuth axis respectively, and transposition rule is different;

Step 3: association system state equation is determined, get the attitude error of inertial navigation system 1 and inertial navigation system 2, velocity error, site error state difference be association system state, 16 error states are:

x＝[(φ _N1-φ _N2) (φ _E1-φ _E2) (φ _D1-φ _D2) (δv _N1-δv _N2) (δv _E1-δv _E2)(δL ₁-δL ₂) (δλ ₁-δλ ₂) ε _x1ε _y1ε _x2ε _y2(ε _z1-ε _z2) ▽ _x1▽ _y1▽ _x2▽ _y2] ^T(1)

Namely

x＝[φ _N12φ _E12φ _D12δv _N12δv _E12δL ₁₂δλ ₁₂ε _x1ε _y1ε _x2ε _y2ε _z12▽ _x1▽ _y1▽ _x2▽ _y2] ^T

Wherein, subscript T represents vector or transpose of a matrix, φ _n12=(φ _n1-φ _n2), φ _e12=(φ _e1-φ _e2), φ _d12=(φ _d1-φ _d2) be respectively the difference of inertial navigation system 1 and the attitude error vector of inertial navigation system 2, δ v _n12=(δ v _n1-δ v _n2), δ v _e12=(δ v _e1-δ v _e2) be respectively inertial navigation system 1 and the north orientation of inertial navigation system 2, the difference of east orientation velocity error, δ L ₁₂=(δ L ₁-δ L ₂), δ λ ₁₂=(δ λ ₁-δ λ ₂) be respectively inertial navigation system 1 and the latitude of inertial navigation system 2, the difference of longitude error, ε _x1, ε _x2, ε _y1, ε _y2be respectively the gyroscope constant value drift of inertial navigation system 1 horizontal axis corresponding to the IMU of inertial navigation system 2, ε _z12=(ε _z1-ε _z2) for difference from inertial navigation system 1 sky corresponding to the IMU of inertial navigation system 2 to the gyroscope constant value drift of coordinate axis (around azimuth axis single-shaft-rotation time, level add table zero partially, gyroscope constant value drift is separable, but sky to gyroscope constant value drift inseparable), ▽ _x1, ▽ _x2, ▽ _y1, ▽ _y2what be respectively inertial navigation system 1 horizontal axis corresponding to the IMU of inertial navigation system 2 adds that to show constant value zero inclined, according to association system state determination association system state equation;

Step 4: measurement equation is determined, deduction error in mounting position and the velocity error that causes of lever arm, lacking under extraneous reference information condition, and get 1s and upgrade the speed of inertial navigation system 1,2 once and the difference of position is corresponding measurement amount, amount is measured as:

z(t)＝[δv _N1-δv _N2δv _E1-δv _E2δL ₁-δL ₂δλ ₁-δλ ₂] ^T(2)

Wherein, for the north orientation speed difference of inertial navigation system 1,2, for the east orientation speed difference of inertial navigation system 1,2, for the latitude difference of inertial navigation system 1,2, for the longitude difference of inertial navigation system 1,2, according to state quantity measurement determination measurement equation;

Step 5: Kalman filtering, build Kalman filter according to association system state equation, measurement equation, 1s once measures renewal, to two cover inertial navigation systems gyros separately, adds table zero and partially estimates;

Step 6: inertial navigation performance online is assessed, according to gyro, adds the relative performance of the inclined estimated value of table zero to inertial navigation system 1,2 and assesses, and zero system less than normal is as optimum decision system;

Wherein: the inertial navigation system 1,2 described in step 2 carries out 4 position 8 order rotation modulation transpositions around azimuth axis respectively, and transposition order method of combination is as follows:

1) inertial navigation system 1,2 adopts different transposition order layouts respectively

The transposition order of inertial navigation system 1 is (shown in Fig. 2), namely 8 order transpositions are (shown in Fig. 4): order 1, is rotated counterclockwise 180 ° by A position and arrives C position, stop the Ts time; Order 2, rotates clockwise 90 ° by C position and arrives B position, stop the Ts time; Order 3, rotates clockwise 180 ° by B position and arrives D position, stop the Ts time; Order 4, rotates counterclockwise 90 ° by D position and arrives A position, stop the Ts time; Order 5, rotates counterclockwise 180 ° by A position and arrives C position, stop the Ts time; Order 6, rotates counterclockwise 90 ° by C position and arrives D position, stop the Ts time; Order 7, rotates clockwise 180 ° by D position and arrives B position, stop the Ts time; Order 8, rotates clockwise 90 ° by B position and arrives A position, stop the Ts time;

The transposition order of inertial navigation system 2 is (shown in Fig. 3), namely 8 order transpositions are (shown in Fig. 5): order 1, is turned clockwise 180 ° by A position and arrive C position, stops the Ts time; Order 2, rotates counterclockwise 90 ° by C position and arrives D position, stop the Ts time; Order 3, rotates counterclockwise 180 ° by D position and arrives B position, stop the Ts time; Order 4, rotates clockwise 90 ° by B position and arrives A position, stop the Ts time; Order 5, rotates clockwise 180 ° by A position and arrives C position, stop the Ts time; Order 6, rotates clockwise 90 ° by C position and arrives B position, stop the Ts time; Order 7, rotates counterclockwise 180 ° by B position and arrives D position, stop the Ts time; Order 8, rotates counterclockwise 90 ° by D position and arrives A position, stop the Ts time;

2) inertial navigation system 1,2 adopts identical transposition order layout, but index time phase shifting

Two cover inertial navigation systems all adopt scheme or all adopt scheme, but phase place difference index time (i.e. azimuth axis initial directional different);

Described in step 3 according to association system state determination association system state equation, its method is as follows:

Association system state equation is:

$\stackrel{\·}{x}\left(t\right)=F\left(t\right)x\left(t\right)+G\left(t\right)w\left(t\right)---\left(3\right)$

Wherein,

X (t) is system state,

x＝[φ _N12φ _E12φ _D12δv _N12δv _E12δL ₁₂δλ ₁₂ε _x1ε _y1ε _x2ε _y2ε _z12▽ _x1▽ _y1▽ _x2▽ _y2] ^T；

$F\left(t\right)=\left[\begin{array}{c}{F}_u\left(t\right)\\ 0_{9\×16}\end{array}\right]$ For state-transition matrix, in formula, each element is,

$F_u\left(t\right)=\left[\begin{array}{ccccc}{A}_1& A_2& A_3& A_4& 0_{3\×4}\\ A_5& A_6& A_7& 0_{2\×5}& A_8\\ 0_{2\×3}& A_9& A_{10}& 0_{2\×5}& 0_{2\×4}\end{array}\right]$

$A_1=\left[\begin{array}{ccc}0& -\frac{v_E\tan L}{R_E+h}-{\mathrm{\ω}}_{ie}\sin L& \frac{v_N}{R_N+h}\\ \frac{v_E\tan L}{R_E+h}+{\mathrm{\ω}}_{ie}\sin L& 0& {\mathrm{\ω}}_{ie}\cos L+\frac{v_E}{R_E+h}\\ -\frac{v_N}{R_N+h}& -{\mathrm{\ω}}_{ie}\cos L-\frac{v_E}{R_E+h}& 0\end{array}\right]$

$A_2=\left[\begin{array}{cc}0& \frac{1}{R_E+h}\\ -\frac{1}{R_N+h}& 0\\ 0& -\frac{\tan L}{R_E+h}\end{array}\right],A_3=\left[\begin{array}{cc}-{\mathrm{\ω}}_{ie}\sin L& 0\\ 0& 0\\ -{\mathrm{\ω}}_{ie}\cos L-\frac{v_E}{(R_E+h){\cos }^{2}L}& 0\end{array}\right]$

$A_4=\left[\begin{array}{ccccc}-C_{s1}^n(1,1)& -C_{s1}^n(1,2)& C_{s2}^n(1,1)& C_{s2}^n(1,2)& 0\\ -C_{s1}^n(2,1)& -C_{s1}^n(2,2)& C_{s2}^n(2,1)& C_{s2}^n(2,2)& 0\\ 0& 0& 0& 0& -1\end{array}\right],A_5=\left[\begin{array}{ccc}0& -f_D& f_E\\ f_D& 0& -f_N\end{array}\right]$

$A_6=\left[\begin{array}{cc}0& -2{\mathrm{\ω}}_{ie}\sin L-2\frac{v_E\tan L}{R_E+h}\\ \frac{v_E\tan L}{R_E+h}+2{\mathrm{\ω}}_{ie}\sin L& \frac{v_N\tan L}{R_N+h}\end{array}\right]$

$A_7=\left[\begin{array}{cc}-v_E(2{\mathrm{\ω}}_{ie}\cos L+\frac{v_E}{R_E{\cos }^{2}L})& 0\\ 2{\mathrm{\ω}}_{ie}{v}_N\cos L+\frac{v_N{v}_E}{R_E{\cos }^{2}L}& 0\end{array}\right]$

$A_8=\left[\begin{array}{cccc}{C}_{s1}^n(1,1)& C_{s1}^n(1,2)& -C_{s2}^n(1,1)& -C_{s2}^n(1,2)\\ C_{s1}^n(2,1)& C_{s1}^n(2,2)& -C_{s2}^n(2,1)& -C_{s2}^n(2,2)\end{array}\right],A_9=\left[\begin{array}{cc}\frac{1}{R_N+h}& 0\\ 0& \frac{\sec L}{R_E+h}\end{array}\right]$

$A_{10}=\left[\begin{array}{cc}0& 0\\ 0& \frac{v_E\tan L}{R_E\cos L}\end{array}\right]$

Wherein, v _efor carrier east orientation speed, v _nfor carrier north orientation speed, ω _iefor rotational-angular velocity of the earth, R _nfor radius of meridional section, R _efor chordwise curvature radius, h is carrier height, f _n, f _e, f _dbe respectively north orientation, east orientation, to than force value, represent the respective element (i represents capable, and j represents row) of direction cosine matrix between the IMU coordinate system of inertial navigation 1,2 and geographic coordinate system respectively;

$w\left(t\right)={\left[\begin{array}{cccccccccc}{w}_{{\mathrm{\ϵ}}_{x1}}& w_{{\mathrm{\ϵ}}_{y1}}& w_{{\mathrm{\ϵ}}_{x2}}& w_{{\mathrm{\ϵ}}_{y2}}& w_{{\mathrm{\ϵ}}_{z1}}& -w_{{\mathrm{\ϵ}}_{z2}}& w_{{\▿}_{x1}}& w_{{\▿}_{y1}}& w_{{\▿}_{x2}}& w_{{\▿}_{y2}}\end{array}\right]}^T$ For system noise, wherein, for the gyro of inertial navigation system 1 horizontal axis corresponding to the IMU of inertial navigation system 2 exports random noise, for inertial navigation system 1 sky corresponding to the IMU of inertial navigation system 2 to export the difference of random noise to the gyro of coordinate axis, for adding of inertial navigation system 1 horizontal axis corresponding to the IMU of inertial navigation system 2 is shown to export random noise;

$G\left(t\right)=\left[\begin{array}{cc}{B}_1& 0_{3\×4}\\ 0_{2\×5}& B_2\\ 0_{11\×5}& 0_{11\×4}\end{array}\right]$ For system noise matrix, wherein, B ₁=A ₄, B ₂=A ₈;

According to state quantity measurement determination measurement equation in step 4, its method is as follows:

Measurement equation is:

z(t)＝Hx(t)+ν(t) (4)

Wherein, ν (t) is measurement noise, $H=\left[\begin{array}{cccc}{0}_{2\×3}& I_{2\×2}& 0_{2\×2}& 0_{2\×9}\\ 0_{2\×3}& 0_{2\×2}& I_{2\×2}& 0_{2\×9}\end{array}\right]$ For measurement matrix, I _{2 × 2}for second order unit matrix;

During two inertial navigation associating rotation modulation strategy layout, rotation modulation also comprises the dual-axis rotation modulation around azimuth axis and transverse axis, now increases the sky of inertial navigation system 1,2 to gyro zero ε partially _z1, ε _z2, and the sky of inertial navigation system 1,2 is to adding table zero ▽ partially _z1, ▽ _z2, as association system state, association system state is

x＝[(φ _N1-φ _N2) (φ _E1-φ _E2) (φ _D1-φ _D2) (δv _N1-δv _N2) (δv _E1-δv _E2) (δL ₁-δL ₂) (5)

(δλ ₁-δλ ₂) ε _x1ε _y1ε _z1ε _x2ε _y2ε _z2▽ _x1▽ _y1▽ _z1▽ _x2▽ _y2▽ _z2] ^T

Build corresponding state equation and measurement equation according to association system state, and to gyro, add table zero and partially estimate, according to gyro, add table zero estimated value partially, online evaluation carried out to system performance;

This pair of inertial navigation associating rotation modulation navigation and online relative performance appraisal procedure can be applicable to the assessment of overlapping relative performance between two between inertial navigation more, as long as make the transposition rule of different inertial navigation system different, error has complementarity, united state equation can be built respectively, access speed, position difference are as measurement amount, carry out Kalman filtering, estimate gyro, add table zero partially, online evaluation is carried out to system performance.

Compared with prior art, the invention has the beneficial effects as follows:

1) the present invention has fully utilized the information of boat-carrying redundant configuration inertial navigation system (general naval vessel carries two cover inertial navigation systems), changes the present situation that the cold and hot back-up job pattern of current boat-carrying inertial navigation system causes the wasting of resources.

2) by the reasonable layout to two inertial navigation associating rotation modulation strategy, the error characteristics of double ionertial navigation system are made to present difference, with the difference of the navigational parameter of double ionertial navigation system for measurement information, build Kalman filter, to double ionertial navigation system gyro separately, add table zero and partially estimate, according to gyro, add table zero estimated value partially, online evaluation is carried out to system performance, changes the present situation that current boat-carrying inertial navigation system performance cannot carry out online evaluation.

3) improve the effect of information fusion between many cover inertial navigation systems, during diagnosis and long boat to inertial navigation system fault, under condition, the guarantee of navigation accuracy has positive effect.

Accompanying drawing explanation

Fig. 1 is the schematic flow sheet of the inventive method;

Fig. 2 is the single-shaft-rotation 4 position 8 order rotation modulation transposition figure of inertial navigation system 1IMU;

Fig. 3 is the single-shaft-rotation 4 position 8 order rotation modulation transposition figure of inertial navigation system 2IMU;

Fig. 4 is the single-shaft-rotation 4 position 8 order rotation modulation transposition sequential chart of inertial navigation system 1IMU;

Fig. 5 is the single-shaft-rotation 4 position 8 order rotation modulation transposition sequential chart of inertial navigation system 2IMU;

Fig. 6 is the vertical view of two cover inertial navigation system associating rotation modulation transposition sequential;

Fig. 7 is that inertial navigation system 1 adopts the navigation of two inertial navigation associating rotation modulation to estimate that two the horizontal gyros zero obtained are inclined with online relative performance appraisal procedure;

Fig. 8 is that inertial navigation system 2 adopts the navigation of two inertial navigation associating rotation modulation to estimate that two the horizontal gyros zero obtained are inclined with online relative performance appraisal procedure;

Fig. 9 is that inertial navigation system 1,2 adopts the navigation of two inertial navigation associating rotation modulation to estimate that two skies obtained are to gyro zero-deviation value with online relative performance appraisal procedure;

It is inclined that Figure 10 is that inertial navigation system 1 adopts the navigation of two inertial navigation associating rotation modulation and online relative performance appraisal procedure to estimate that two levels obtained add table zero;

It is inclined that Figure 11 is that inertial navigation system 2 adopts the navigation of two inertial navigation associating rotation modulation and online relative performance appraisal procedure to estimate that two levels obtained add table zero.

Embodiment

Below in conjunction with accompanying drawing, a kind of optimal way in the present invention is described in further detail.

Step one: coordinate system defines

Definition navigational coordinate system (n system) is local horizontal geographic coordinate system, coordinate axis points to north orientation-east orientation-ground respectively to (N-E-D), carrier coordinate system (b system) coordinate axis is respectively along the roll axle-pitch axis-yaw axis (front-right-under) of carrier, and Inertial Measurement Unit (IMU) coordinate system of inertial navigation system 1,2 is respectively s ₁, s ₂, coordinate axis is pointed to and is defined with carrier coordinate system.

Step 2: associating rotation modulation strategy layout

Inertial navigation system 1,2 carries out 4 position 8 order rotation modulation transpositions around azimuth axis respectively, and inertial navigation system 1,2 adopts different transposition order layouts respectively;

The transposition order of inertial navigation system 1 is (shown in Fig. 2), namely 8 order transpositions are (shown in Fig. 4): order 1, is rotated counterclockwise 180 ° by A position and arrives C position, stop the Ts time; Order 2, rotates clockwise 90 ° by C position and arrives B position, stop the Ts time; Order 3, rotates clockwise 180 ° by B position and arrives D position, stop the Ts time; Order 4, rotates counterclockwise 90 ° by D position and arrives A position, stop the Ts time; Order 5, rotates counterclockwise 180 ° by A position and arrives C position, stop the Ts time; Order 6, rotates counterclockwise 90 ° by C position and arrives D position, stop the Ts time; Order 7, rotates clockwise 180 ° by D position and arrives B position, stop the Ts time; Order 8, rotates clockwise 90 ° by B position and arrives A position, stop the Ts time;

The transposition order of inertial navigation system 2 is (shown in Fig. 3), namely 8 order transpositions are (shown in Fig. 5): order 1, is turned clockwise 180 ° by A position and arrive C position, stops the Ts time; Order 2, rotates counterclockwise 90 ° by C position and arrives D position, stop the Ts time; Order 3, rotates counterclockwise 180 ° by D position and arrives B position, stop the Ts time; Order 4, rotates clockwise 90 ° by B position and arrives A position, stop the Ts time; Order 5, rotates clockwise 180 ° by A position and arrives C position, stop the Ts time; Order 6, rotates clockwise 90 ° by C position and arrives B position, stop the Ts time; Order 7, rotates counterclockwise 180 ° by B position and arrives D position, stop the Ts time; Order 8, rotates counterclockwise 90 ° by D position and arrives A position, stop the Ts time;

Two cover inertial navigation systems rotate according to respective transposition order loop cycle, when inertial navigation system 1 adopts associating rotation modulation with the IMU of inertial navigation system 2, corresponding orientation Eulerian angle change by predetermined rule, as shown in Figure 2 and Figure 3 (Fig. 4, Fig. 5 are corresponding sequential chart, and Fig. 6 is transposition sequential vertical view), and the IMU coordinate system s of inertial navigation system 1 ₁with the IMU coordinate system s of inertial navigation system 2 ₂between be followed successively by equidirectional and in the other direction.

Step 3: association system state equation is determined

Get the attitude error of inertial navigation system 1 and inertial navigation system 2, velocity error, site error state difference be association system state, 16 error states are:

x＝[(φ _N1-φ _N2) (φ _E1-φ _E2) (φ _D1-φ _D2) (δv _N1-δv _N2) (δv _E1-δv _E2)(δL ₁-δL ₂) (δλ ₁-δλ ₂) ε _x1ε _y1ε _x2ε _y2(ε _z1-ε _z2) ▽ _x1▽ _y1▽ _x2▽ _y2] ^T(6)

Namely

x＝[φ _N12φ _E12φ _D12δv _N12δv _E12δL ₁₂δλ ₁₂ε _x1ε _y1ε _x2ε _y2ε _z12▽ _x1▽ _y1▽ _x2▽ _y2] ^T

Wherein, subscript T represents vector or transpose of a matrix, φ _n12=(φ _n1-φ _n2), φ _e12=(φ _e1-φ _e2), φ _d12=(φ _d1-φ _d2) be respectively the difference of inertial navigation system 1 and the attitude error vector of inertial navigation system 2, δ v _n12=(δ v _n1-δ v _n2), δ v _e12=(δ v _e1-δ v _e2) be respectively inertial navigation system 1 and the north orientation of inertial navigation system 2, the difference of east orientation velocity error, δ L ₁₂=(δ L ₁-δ L ₂), δ λ ₁₂=(δ λ ₁-δ λ ₂) be respectively inertial navigation system 1 and the latitude of inertial navigation system 2, the difference of longitude error, ε _x1, ε _x2, ε _y1, ε _y2be respectively the gyroscope constant value drift of inertial navigation system 1 horizontal axis corresponding to the IMU of inertial navigation system 2, ε _z12=(ε _z1-ε _z2) for difference from inertial navigation system 1 sky corresponding to the IMU of inertial navigation system 2 to the gyroscope constant value drift of coordinate axis (around azimuth axis single-shaft-rotation time, level add table zero partially, gyroscope constant value drift is separable, but sky to gyroscope constant value drift inseparable), ▽ _x1, ▽ _x2, ▽ _y1, ▽ _y2what be respectively inertial navigation system 1 horizontal axis corresponding to the IMU of inertial navigation system 2 adds that to show constant value zero inclined;

It is as follows according to association system state determination association system state equation,

Association system state equation is:

$\stackrel{\·}{x}\left(t\right)=F\left(t\right)x\left(t\right)+G\left(t\right)w\left(t\right)---\left(7\right)$

Wherein,

X (t) is system state,

x＝[φ _N12φ _E12φ _D12δv _N12δv _E12δL ₁₂δλ ₁₂ε _x1ε _y1ε _x2ε _y2ε _z12▽ _x1▽ _y1▽ _x2▽ _y2] ^T

$F\left(t\right)=\left[\begin{array}{c}{F}_u\left(t\right)\\ 0_{9\×16}\end{array}\right]$ For state-transition matrix, in formula, each element is,

$F_u\left(t\right)=\left[\begin{array}{ccccc}{A}_1& A_2& A_3& A_4& 0_{3\×4}\\ A_5& A_6& A_7& 0_{2\×5}& A_8\\ 0_{2\×3}& A_9& A_{10}& 0_{2\×5}& 0_{2\×4}\end{array}\right]$

$A_1=\left[\begin{array}{ccc}0& -\frac{v_E\tan K}{R_E+h}-{\mathrm{\ω}}_{ie}\sin L& \frac{v_N}{R_N+h}\\ \frac{v_E\tan L}{R_E+h}+{\mathrm{\ω}}_{ie}\sin L& 0& {\mathrm{\ω}}_{ie}\cos L+\frac{v_E}{R_E+h}\\ -\frac{v_N}{R_N+h}& -{\mathrm{\ω}}_{ie}\cos L-\frac{v_E}{R_E+h}& 0\end{array}\right]$

$A_2=\left[\begin{array}{cc}0& \frac{1}{R_E+h}\\ -\frac{1}{R_N+h}& 0\\ 0& -\frac{\tan L}{R_E+h}\end{array}\right],A_3=\left[\begin{array}{cc}-{\mathrm{\ω}}_{ie}\sin L& 0\\ 0& 0\\ -{\mathrm{\ω}}_{ie}\cos L-\frac{v_E}{(R_E+h){\cos }^{2}L}& 0\end{array}\right]$

$A_4=\left[\begin{array}{ccccc}-C_{s1}^n(1,1)& -C_{s1}^n(1,2)& C_{s2}^n(1,1)& C_{s2}^n(1,2)& 0\\ -C_{s1}^n(2,1)& -C_{s1}^n(2,2)& C_{s2}^n(2,1)& C_{s2}^n(2,2)& 0\\ 0& 0& 0& 0& -1\end{array}\right],A_5=\left[\begin{array}{ccc}0& -f_D& f_E\\ f_D& 0& -f_N\end{array}\right]$

$A_6=\left[\begin{array}{cc}0& -2{\mathrm{\ω}}_{ie}\sin L-2\frac{v_E\tan L}{R_E+h}\\ \frac{v_E\tan L}{R_E+h}+2{\mathrm{\ω}}_{ie}\sin L& \frac{v_N\tan L}{R_N+h}\end{array}\right]$

$A_7=\left[\begin{array}{cc}-v_E(2{\mathrm{\ω}}_{ie}\cos L+\frac{v_E}{R_E{\cos }^{2}L})& 0\\ 2{\mathrm{\ω}}_{ie}{v}_N\cos L+\frac{v_N{v}_E}{R_E{\cos }^{2}L}& 0\end{array}\right]$

$A_8=\left[\begin{array}{cccc}{C}_{s1}^n(1,1)& C_{s1}^n(1,2)& -C_{s2}^n(1,1)& -C_{s2}^n(1,2)\\ C_{s1}^n(2,1)& C_{s1}^n(2,2)& -C_{s2}^n(2,1)& -C_{s2}^n(2,2)\end{array}\right],A_9=\left[\begin{array}{cc}\frac{1}{R_N+h}& 0\\ 0& \frac{\sec L}{R_E+h}\end{array}\right]$

$A_{10}=\left[\begin{array}{cc}0& 0\\ 0& \frac{v_E\tan L}{R_E\cos L}\end{array}\right]$

Wherein, v _efor carrier east orientation speed, v _nfor carrier north orientation speed, ω _iefor rotational-angular velocity of the earth, R _nfor radius of meridional section, R _efor chordwise curvature radius, h is carrier height, f _n, f _e, f _dbe respectively north orientation, east orientation, to than force value, represent the respective element (i represents capable, and j represents row) of direction cosine matrix between the IMU coordinate system of inertial navigation 1,2 and geographic coordinate system respectively;

$w\left(t\right)={\left[\begin{array}{cccccccccc}{w}_{{\mathrm{\ϵ}}_{x1}}& w_{{\mathrm{\ϵ}}_{y1}}& w_{{\mathrm{\ϵ}}_{x2}}& w_{{\mathrm{\ϵ}}_{y2}}& w_{{\mathrm{\ϵ}}_{z1}}& -w_{{\mathrm{\ϵ}}_{z2}}& w_{{\▿}_{x1}}& w_{{\▿}_{y1}}& w_{{\▿}_{x2}}& w_{{\▿}_{y2}}\end{array}\right]}^T$ For system noise, wherein, for the gyro of inertial navigation system 1 horizontal axis corresponding to the IMU of inertial navigation system 2 exports random noise, for inertial navigation system 1 sky corresponding to the IMU of inertial navigation system 2 to export the difference of random noise to the gyro of coordinate axis, for adding of inertial navigation system 1 horizontal axis corresponding to the IMU of inertial navigation system 2 is shown to export random noise;

$G\left(t\right)=\left[\begin{array}{cc}{B}_1& 0_{3\×4}\\ 0_{2\×5}& B_2\\ 0_{11\×5}& 0_{11\×4}\end{array}\right]$ For system noise matrix, wherein, B ₁=A ₄, B ₂=A ₈.

Step 4: measurement equation is determined

Deduction error in mounting position and the velocity error that causes of lever arm, lacking under extraneous reference information condition, and get 1s and upgrade the speed of inertial navigation system 1,2 once and the difference of position is corresponding measurement amount, amount is measured as:

z(t)＝[δv _N1-δv _N2δv _E1-δv _E2δL ₁-δL ₂δλ ₁-δλ ₂] ^T(8)

Wherein, for the north orientation speed difference of inertial navigation system 1,2, for the east orientation speed difference of inertial navigation system 1,2, for the latitude difference of inertial navigation system 1,2, for the longitude difference of inertial navigation system 1,2;

It is as follows according to state quantity measurement determination measurement equation,

z(t)＝Hx(t)+ν(t) (9)

Wherein, ν (t) is measurement noise, $H=\left[\begin{array}{cccc}{0}_{2\×3}& I_{2\×2}& 0_{2\×2}& 0_{2\×9}\\ 0_{2\×3}& 0_{2\×2}& I_{2\×2}& 0_{2\×9}\end{array}\right]$ For measurement matrix, I _{2 × 2}for second order unit matrix.

Step 5: Kalman filtering

Build Kalman filter according to association system state equation, measurement equation, 1s once measures renewal, to two cover inertial navigation systems gyros separately, adds table zero and partially estimates.

Step 6: inertial navigation performance online is assessed, according to gyro, adds the relative performance of the inclined estimated value of table zero to inertial navigation system 1,2 and assesses, and zero system less than normal is as optimum decision system.

The navigation of two inertial navigation associating rotation modulation can be verified by Matlab hardware-in-the-loop simulation with online relative performance appraisal procedure effect, and emulation arranges as follows:

Two cover inertial navigation positions are north latitude 30 °, and east longitude 120 °, all remains static, and rotate according to associating rotation modulation strategy, be 442s at each position residence time Ts, the time of rotating 180 °, 90 ° is 8s, and a complete rotation modulation cycle is 3600s.The horizontal initial attitude angle of two cover inertial navigations is 0 °, orientation initial attitude angle is 45 °, " error; inertial navigation 2 position angle adds-30 " errors that inertial navigation 1 position angle adds 30, ignore horizontal attitude angle error, ignore the impact of scale factor error, scale factory non-linearity error and alignment error, lever arm error simultaneously.

Investigation two inertial navigation associating rotation modulation navigates and online relative performance appraisal procedure is inclined to gyro zero, add the inclined estimation effect of table zero.

Inertial navigation 1 emulate produce gyro angle increment, add in indicated airspeed degree incremental data according to following arrange add zero inclined:

X gyro: 0.001 °/h Y gyro :-0.001 °/h Z gyro :-0.0003 °/h

X adds table: 0.5 × 10 ^-5g Y adds table :-0.5 × 10 ^-5g

Inertial navigation 2 emulate produce gyro angle increment, add in indicated airspeed degree incremental data according to following arrange add zero inclined:

X gyro :-0.002 °/h Y gyro: 0.002 °/h Z gyro: 0.0005 °/h

X adds table :-1 × 10 ^-5g Y adds table: 1 × 10 ^-5g

It is independent to loop, ignores sky to adding table zero error partially.

Two cover inertial navigations gyro, add table noise be actual inertial navigation system stationary state down-sampling obtain incremental data deduction average after remainder.

Simulation time is set to 72h, and two cover inertial navigation system sample frequency are 200Hz, and inertial reference calculation frequency is 100Hz.

From Fig. 7, Fig. 8 two overlaps the inertial navigation system estimation condition that horizontal gyro zero is inclined separately and from Figure 10, Figure 11 two overlap inertial navigation system separately level add the inclined estimation condition of table zero and can find out, in 72h simulation time, gyro zero is inclined, add the inclined setting value of table zero all can estimate, under single shaft associating rotation modulation condition, it also can estimate to obtain (shown in Fig. 9) to gyro zero-deviation value, if adopt twin shaft associating rotation modulation, two cover inertial navigation skies separately also can estimate partially to gyro zero, and then according to estimating that the gyro zero obtained is inclined, add table zero situation partially, can judge that inertial navigation 1 is as preferred inertial navigation system, complete the assessment of inertial navigation performance online.

Below be only the preferred embodiment of the present invention, protection scope of the present invention is not limited in above-described embodiment, and all technical schemes belonged under thinking of the present invention all belong to protection scope of the present invention.It should be pointed out that for those skilled in the art, some improvements and modifications without departing from the principles of the present invention, should be considered as falling into protection scope of the present invention.

Claims (4)

1. the navigation of two inertial navigation associating rotation modulation and an online relative performance appraisal procedure, is characterized in that comprising the following steps:

Step one: coordinate system defines, definition navigational coordinate system (n system) is local horizontal geographic coordinate system, coordinate axis points to north orientation-east orientation-ground respectively to (N-E-D), carrier coordinate system (b system) coordinate axis is respectively along the roll axle-pitch axis-yaw axis (front-right-under) of carrier, and Inertial Measurement Unit (IMU) coordinate system of inertial navigation system 1,2 is respectively s ₁, s ₂, coordinate axis is pointed to and is defined with carrier coordinate system;

Step 2: associating rotation modulation strategy layout, inertial navigation system 1,2 carries out 4 position 8 order rotation modulation transpositions around azimuth axis respectively, and transposition rule is different;

Step 3: association system state equation is determined, get the attitude error of inertial navigation system 1 and inertial navigation system 2, velocity error, site error state difference be association system state, 16 error states are:

x＝[(φ _N1-φ _N2) (φ _E1-φ _E2) (φ _D1-φ _D2) (δv _N1-δv _N2) (δv _E1-δv _E2)

(δL ₁-δL ₂) (δλ ₁-δλ ₂) ε _x1ε _y1ε _x2ε _y2(ε _z1-ε _z2) ▽ _x1▽ _y1▽ _x2▽ _y2] ^T(1)

Namely

x＝[φ _N12φ _E12φ _D12δv _N12δv _E12δL ₁₂δλ ₁₂

ε _x1ε _y1ε _x2ε _y2ε _z12▽ _x1▽ _y1▽ _x2▽ _y2] ^T

Wherein, subscript T represents vector or transpose of a matrix, φ _n12=(φ _n1-φ _n2), φ _e12=(φ _e1-φ _e2), φ _d12=(φ _d1-φ _d2) be respectively the difference of inertial navigation system 1 and the attitude error vector of inertial navigation system 2, δ v _n12=(δ v _n1-δ v _n2), δ v _e12=(δ v _e1-δ v _e2) be respectively inertial navigation system 1 and the north orientation of inertial navigation system 2, the difference of east orientation velocity error, δ L ₁₂=(δ L ₁-δ L ₂), δ λ ₁₂=(δ λ ₁-δ λ ₂) be respectively inertial navigation system 1 and the latitude of inertial navigation system 2, the difference of longitude error, ε _x1, ε _x2, ε _y1, ε _y2be respectively the gyroscope constant value drift of inertial navigation system 1 horizontal axis corresponding to the IMU of inertial navigation system 2, ε _z12=(ε _z1-ε _z2) for difference from inertial navigation system 1 sky corresponding to the IMU of inertial navigation system 2 to the gyroscope constant value drift of coordinate axis (around azimuth axis single-shaft-rotation time, level add table zero partially, gyroscope constant value drift is separable, but sky to gyroscope constant value drift inseparable), ▽ _x1, ▽ _x2, ▽ _y1, ▽ _y2what be respectively inertial navigation system 1 horizontal axis corresponding to the IMU of inertial navigation system 2 adds that to show constant value zero inclined, according to association system state determination association system state equation;

Step 4: measurement equation is determined, deduction error in mounting position and the velocity error that causes of lever arm, lacking under extraneous reference information condition, and get 1s and upgrade the speed of inertial navigation system 1,2 once and the difference of position is corresponding measurement amount, amount is measured as:

z(t)＝[δv _N1-δv _N2δv _E1-δv _E2δL ₁-δL ₂δλ ₁-δλ ₂] ^T(2)

Wherein, for the north orientation speed difference of inertial navigation system 1,2, for the east orientation speed difference of inertial navigation system 1,2, for the latitude difference of inertial navigation system 1,2, for the longitude difference of inertial navigation system 1,2, according to state quantity measurement determination measurement equation;

Step 5: Kalman filtering, build Kalman filter according to association system state equation, measurement equation, 1s once measures renewal, to two cover inertial navigation systems gyros separately, adds table zero and partially estimates;

Step 6: inertial navigation performance online is assessed, according to gyro, adds the relative performance of the inclined estimated value of table zero to inertial navigation system 1,2 and assesses, and zero system less than normal is as optimum decision system.

2. the navigation of one according to claim 1 two inertial navigation associating rotation modulation and online relative performance appraisal procedure, is characterized in that:

Inertial navigation system 1,2 described in step 2 carries out 4 position 8 order rotation modulation transpositions around azimuth axis respectively, and transposition order method of combination is as follows:

1) inertial navigation system 1,2 adopts different transposition order layouts respectively

The transposition order of inertial navigation system 1 is $\frac{\mathrm{\π}}{4}\→\frac{5\mathrm{\π}}{4}\→\frac{3\mathrm{\π}}{4}\→-\frac{\mathrm{\π}}{4}\→\frac{\mathrm{\π}}{4}\→-\frac{3\mathrm{\π}}{4}\→-\frac{\mathrm{\π}}{4}\→\frac{3\mathrm{\π}}{4},$ Namely 8 order transpositions are: order 1, are rotated counterclockwise 180 ° and arrive C position, stop the Ts time by A position; Order 2, rotates clockwise 90 ° by C position and arrives B position, stop the Ts time; Order 3, rotates clockwise 180 ° by B position and arrives D position, stop the Ts time; Order 4, rotates counterclockwise 90 ° by D position and arrives A position, stop the Ts time; Order 5, rotates counterclockwise 180 ° by A position and arrives C position, stop the Ts time; Order 6, rotates counterclockwise 90 ° by C position and arrives D position, stop the Ts time; Order 7, rotates clockwise 180 ° by D position and arrives B position, stop the Ts time; Order 8, rotates clockwise 90 ° by B position and arrives A position, stop the Ts time;

The transposition order of inertial navigation system 2 is $\frac{\mathrm{\π}}{4}\→-\frac{3\mathrm{\π}}{4}\→-\frac{\mathrm{\π}}{4}\→\frac{3\mathrm{\π}}{4}\→\frac{\mathrm{\π}}{4}\→\frac{5\mathrm{\π}}{4}\→\frac{3\mathrm{\π}}{4}\→-\frac{\mathrm{\π}}{4},$ Namely 8 order transpositions are: order 1, and being turned clockwise 180 ° by A position arrives C position, stop the Ts time; Order 2, rotates counterclockwise 90 ° by C position and arrives D position, stop the Ts time; Order 3, rotates counterclockwise 180 ° by D position and arrives B position, stop the Ts time; Order 4, rotates clockwise 90 ° by B position and arrives A position, stop the Ts time; Order 5, rotates clockwise 180 ° by A position and arrives C position, stop the Ts time; Order 6, rotates clockwise 90 ° by C position and arrives B position, stop the Ts time; Order 7, rotates counterclockwise 180 ° by B position and arrives D position, stop the Ts time; Order 8, rotates counterclockwise 90 ° by D position and arrives A position, stop the Ts time;

2) inertial navigation system 1,2 adopts identical transposition order layout, but index time phase shifting

Two cover inertial navigation systems all adopt $\frac{\mathrm{\π}}{4}\→\frac{5\mathrm{\π}}{4}\→\frac{3\mathrm{\π}}{4}\→-\frac{\mathrm{\π}}{4}\→\frac{\mathrm{\π}}{4}\→-\frac{3\mathrm{\π}}{4}\→-\frac{\mathrm{\π}}{4}\→\frac{3\mathrm{\π}}{4}$ Scheme or all adopt $\frac{\mathrm{\π}}{4}\→-\frac{3\mathrm{\π}}{4}\→-\frac{\mathrm{\π}}{4}\→\frac{3\mathrm{\π}}{4}\→\frac{\mathrm{\π}}{4}\→\frac{5\mathrm{\π}}{4}\→\frac{3\mathrm{\π}}{4}\→-\frac{\mathrm{\π}}{4}$ Scheme, but phase place difference index time (i.e. azimuth axis initial directional different);

Described in step 3 according to association system state determination association system state equation, its method is as follows:

Association system state equation is:

$\stackrel{\·}{x}\left(t\right)=F\left(t\right)x\left(t\right)+G\left(t\right)w\left(t\right)---\left(3\right)$

Wherein,

X (t) is system state,

x＝[φ _N12φ _E12φ _D12δv _N12δv _E12δL ₁₂δλ ₁₂

ε _x1ε _y1ε _x2ε _y2ε _z12▽ _x1▽ _y1▽ _x2▽ _y2] ^T；

$F\left(t\right)=\left[\begin{array}{c}{F}_u\left(t\right)\\ 0_{9\×16}\end{array}\right]$ For state-transition matrix, in formula, each element is,

$F_u\left(t\right)=\left[\begin{array}{ccccc}{A}_1& A_2& A_3& A_4& 0_{3\×4}\\ A_5& A_6& A_7& 0_{2\×5}& A_8\\ 0_{2\×3}& A_9& A_{10}& 0_{2\×5}& 0_{2\×4}\end{array}\right]$

$A_1=\left[\begin{array}{ccc}0& -\frac{v_E\tan L}{R_E+h}-{\mathrm{\ω}}_{ie}\sin L& \frac{v_N}{R_N+h}\\ \frac{v_E\tan L}{R_E+h}+{\mathrm{\ω}}_{ie}\sin L& 0& {\mathrm{\ω}}_{ie}\cos L+\frac{v_E}{R_E+h}\\ -\frac{v_N}{R_N+h}& -{\mathrm{\ω}}_{ie}\cos L-\frac{v_E}{R_E+h}& 0\end{array}\right]$

$A_2=\left[\begin{array}{cc}0& \frac{1}{R_E+h}\\ -\frac{1}{R_N+h}& 0\\ 0& -\frac{\tan L}{R_E+h}\end{array}\right],A_3=\left[\begin{array}{cc}-{\mathrm{\ω}}_{ie}\sin L& 0\\ 0& 0\\ -{\mathrm{\ω}}_{ie}\cos L-\frac{v_E}{(R_E+h){\cos }^{2}L}& 0\end{array}\right]$

$A_4=\left[\begin{array}{ccccc}-C_{s1}^n(1,1)& -C_{s1}^n(1,2)& C_{s2}^n(1,1)& C_{s2}^n(1,2)& 0\\ -C_{s1}^n(2,1)& -C_{s1}^n(2,2)& C_{s2}^n(2,1)& C_{s2}^n(2,2)& 0\\ 0& 0& 0& 0& -1\end{array}\right],A_5=\left[\begin{array}{ccc}0& -f_D& f_E\\ f_D& 0& -f_N\end{array}\right]$

$A_6=\left[\begin{array}{cc}0& -2{\mathrm{\ω}}_{ie}\sin L-2\frac{v_E\tan L}{R_E+h}\\ \frac{v_E\tan L}{R_E+h}+2{\mathrm{\ω}}_{ie}\sin L& \frac{v_N\tan L}{R_N+h}\end{array}\right]$

$A_7=\left[\begin{array}{cc}-v_E(2{\mathrm{\ω}}_{ie}\cos L+\frac{v_E}{R_E{\cos }^{2}L})& 0\\ 2{\mathrm{\ω}}_{ie}{v}_N\cos L+\frac{v_N{v}_E}{R_E{\cos }^{2}L}& 0\end{array}\right]$

$A_8=\left[\begin{array}{cccc}{C}_{s1}^n(1,1)& C_{s1}^n(1,2)& -C_{s2}^n(1,1)& -C_{s2}^n(1,2)\\ C_{s1}^n(2,1)& C_{s1}^n(2,2)& -C_{s2}^n(2,1)& -C_{s2}^n(2,2)\end{array}\right],A_9=\left[\begin{array}{cc}\frac{1}{R_N+h}& 0\\ 0& \frac{\sec L}{R_E+h}\end{array}\right]$

$A_{10}=\left[\begin{array}{cc}0& 0\\ 0& \frac{v_E\tan L}{R_E\cos L}\end{array}\right]$

Wherein, v _efor carrier east orientation speed, v _nfor carrier north orientation speed, ω _iefor rotational-angular velocity of the earth, R _nfor radius of meridional section, R _efor chordwise curvature radius, h is carrier height, f _n, f _e, f _dbe respectively north orientation, east orientation, to than force value, represent the respective element (i represents capable, and j represents row) of direction cosine matrix between the IMU coordinate system of inertial navigation 1,2 and geographic coordinate system respectively;

$w\left(t\right)={\left[\begin{array}{ccccccccc}{w}_{{\mathrm{\ϵ}}_{x1}}& w_{{\mathrm{\ϵ}}_{y1}}& w_{{\mathrm{\ϵ}}_{x2}}& w_{{\mathrm{\ϵ}}_{y2}}& w_{{\mathrm{\ϵ}}_{z1}}-w_{{\mathrm{\ϵ}}_{z2}}& w_{{\▿}_{x1}}& w_{{\▿}_{y1}}& w_{{\▿}_{x2}}& w_{{\▿}_{y2}}\end{array}\right]}^T$ For system noise, wherein, for the gyro of inertial navigation system 1 horizontal axis corresponding to the IMU of inertial navigation system 2 exports random noise, for inertial navigation system 1 sky corresponding to the IMU of inertial navigation system 2 to export the difference of random noise to the gyro of coordinate axis, for adding of inertial navigation system 1 horizontal axis corresponding to the IMU of inertial navigation system 2 is shown to export random noise;

$G\left(t\right)=\left[\begin{array}{cc}{B}_1& 0_{3\×4}\\ 0_{2\×5}& B_2\\ 0_{11\×5}& 0_{11\×4}\end{array}\right]$ For system noise matrix, wherein, B ₁=A ₄, B ₂=A ₈;

According to state quantity measurement determination measurement equation in step 4, its method is as follows:

Measurement equation is:

z(t)＝Hx(t)+ν(t) (4)

Wherein, ν (t) is measurement noise, $H=\left[\begin{array}{cccc}{0}_{2\×3}& I_{2\×2}& 0_{2\×2}& 0_{2\×9}\\ 0_{2\×3}& 0_{2\×2}& I_{2\×2}& 0_{2\×9}\end{array}\right]$ For measurement matrix, I _{2 × 2}for second order unit matrix.

3. the navigation of one according to claim 1 two inertial navigation associating rotation modulation and online relative performance appraisal procedure, it is characterized in that: rotation modulation also comprises the dual-axis rotation modulation around azimuth axis and transverse axis, now increase the sky of inertial navigation system 1,2 to gyro zero ε partially _z1, ε _z2, and the sky of inertial navigation system 1,2 is to adding table zero ▽ partially _z1, ▽ _z2, as association system state, association system state is

x＝[(φ _N1-φ _N2) (φ _E1-φ _E2) (φ _D1-φ _D2) (δv _N1-δv _N2) (δv _E1-δv _E2) (δL ₁-δL ₂)

(δλ ₁-δλ ₂) ε _x1ε _y1ε _z1ε _x2ε _y2ε _z2▽ _x1▽ _y1▽ _z1▽ _x2▽ _y2▽ _z2] ^T(5)

Build corresponding state equation and measurement equation according to association system state, and to gyro, add table zero and partially estimate, according to gyro, add table zero estimated value partially, online evaluation carried out to system performance.

4. the navigation of one according to any one of claim 1 to 3 two inertial navigation associating rotation modulation and online relative performance appraisal procedure, is characterized in that: the method can be applicable to the assessment of relative performance between two between the inertial navigation of many covers.