CN103335649B - A kind of inertial navigation system polar region navigation parameter calculation method - Google Patents

Abstract

The present invention relates to the fields such as airmanship, be specifically related to a kind of inertial navigation system polar region navigation parameter calculation method.The present invention is by building ellipsoid grid heading reference model, utilize the navigation information of inertial navigation system under navigational coordinate system, resolve the navigational parameter being applicable to polar navigation, be applied in inertial navigation system navigation calculation module, inertial navigation is made directly to export polar region navigational parameter, improve inertial navigation system polar navigation performance, meet the polar region safe navigation requirement of carrier.

Description

A kind of inertial navigation system polar region navigation parameter calculation method

Technical field

The present invention relates to the fields such as airmanship, be specifically related to a kind of inertial navigation system polar region navigation parameter calculation method.

Background technology

Along with the further exploitation of the flourish and polar region of aviation, seafaring, correctly carry out polar navigation location, guarantee the safely and effectively navigation of carrier in polar region, more show its importance.

But the navigational environment of polar region is very complicated, affect the safety work normally using and navigate by water personnel of multiple existing navigator.Inertial navigation system has the advantages such as independence, anti-interference, disguise, becomes the navigation means of military a kind of necessity, also seems particularly important in the polar navigation of circumstance complication.But the features such as polar region latitude is high, warp convergence is fast make existing inertial navigation system (navigational coordinate system is not geographic coordinate system) mainly there is following two problems for polar region (except nearly poles region):

1, along with latitude raises the geographical course error of inertial navigation system and geographical velocity error increases.This is because the rotational angular velocity sky raising geographic coordinate system relatively spherical coordinate system along with latitude increases to the component error of calculation, and then the directly related with it navigational parameter resolution error of impact.

2, the geographical course that inertial navigation system resolves can not meet polar navigation demand.The angle this is because constantly change course fast when the Fast Convergent of geographic meridian causes carrier to navigate by water along great circle route, be unfavorable for navigation personnel navigate by water monitoring and navigation paint calculation, therefore geographical course is no longer applicable to polar navigation.

Therefore, be necessary that invention is a kind of and can improve the inertial navigation system polar navigation method that polar navigation performance can meet again polar navigation demand.

Summary of the invention

For the deficiency of background technology, the invention provides a kind of inertial navigation system polar region navigation parameter calculation method, be applied in inertial navigation system navigation calculation module, make inertial navigation directly export polar region navigational parameter.The present invention, by building ellipsoid grid heading reference model, utilizes the navigation information of inertial navigation system under navigational coordinate system, resolves the navigational parameter being applicable to polar navigation, improves inertial navigation system polar navigation performance, meets the polar region safe navigation requirement of carrier.

Technical scheme of the present invention is: a kind of inertial navigation system polar region navigation parameter calculation method, is characterized in that: it comprises the steps:

1st step: the latitude and longitude information resolved according to inertial navigation system navigation calculation module, inertial navigation computer resolves the angle of grid heading reference and geographical heading reference;

2nd step: the angle determined according to the 1st step, inertial navigation computer resolves the rotation relationship matrix of navigational coordinate system and " grid east, grid north, sky " coordinate system;

3rd step: the angle determined according to the 1st step, inertial navigation computer resolves grid course parameter, exports inertial navigation parameter display interface to;

4th step: the rotation relationship matrix determined according to the 2nd step, inertial navigation computer resolves grid velocity parameter, exports inertial navigation parameter display interface to.

Navigational parameter calculation method as above, is characterized in that: the angle of grid heading reference and geographic reference in described step 1 , wherein for geographic latitude, for geographic longitude.

Navigational parameter calculation method as above, is characterized in that: in described step 2, rotation relationship matrix is , p is navigational coordinate system, and t is " grid east, grid north, sky " coordinate system.

Navigational parameter calculation method as above, is characterized in that: in described step 3, grid course parameter is ,wherein for grid course, for inertial navigation exports geographical course.

Navigational parameter calculation method as above, is characterized in that: in described step 4, grid velocity parameter is , wherein for grid east orientation speed and for grid north orientation speed, for navigational coordinate system (p system) Z axis is relative to the position angle of geographic coordinate system (g system) Z axis.

Principal feature of the present invention is as follows:

(1) this method does not change the hardware configuration of inertial navigation system, original navigational parameter resolve in module add the inventive method resolve module, resolve polar navigation parameter, therefore facilitate and directly apply in existing inertial navigation system, and the method both can export geographical course, velocity information, again can output grid course, velocity information.

(2), in certain hour, the grid course precision that the present invention resolves is better than geographical course precision.

(3), in certain hour, the grid velocity precision that the present invention resolves is better than geographical velocity accuracy.

(4) ellipsoid gridline is straight line on polar region Gauss projection drawing, and great circle route is almost projected into grid loxodromic line, the information that the present invention resolves be convenient to navigation personnel navigate by water monitoring and navigation paint calculation.

Accompanying drawing explanation

Fig. 1 is ellipsoid grid heading reference model schematic of the present invention;

Fig. 2 is inertial navigation system polar navigation parameter calculation block diagram of the present invention;

Fig. 3 is geographical course error and grid course error emulation comparative graph;

Fig. 4 is that geographic north is to velocity error and grid north orientation velocity error emulation comparative graph.

Embodiment

Below in conjunction with accompanying drawing, the present invention is described further.

The present invention is based upon on the basis of ellipsoid grid heading reference model, and this model provides heading reference for inertial navigation system polar navigation parameter calculation method, need study some characteristic of ellipsoid grid heading reference model.The characteristic of this model mainly comprises:

(1) definition of ellipsoid gridline;

(2) definition of ellipsoid grid heading reference;

(3) relation of ellipsoid grid heading reference and geographical heading reference.

Some characteristic of 1 pair of ellipsoid grid heading reference model is specifically studied by reference to the accompanying drawings, mainly comprises following three aspects:

(1) ellipsoid gridline definition: be parallel to the elliptical area outline line that meridian plane cutting earth's spheroid is formed, therefore each meridian circle corresponds to gang's ellipsoid gridline.For convenience of using, the present invention adopts the ellipsoid gridline corresponding to Greenwich meridian circle.

(2) definition of grid heading reference: in scope, grid north orientation is the direction pointing to latitude rising along gridline tangent line, in scope, grid north orientation is the direction pointing to latitude reduction along gridline line, and " grid east, grid north, sky " coordinate system (t system) forms right hand rectangular coordinate system.

(3) angle of grid heading reference and geographical heading reference: utilize vector quantities to amass operation relation, solves the angle of two benchmark by the angle solving meridian circle tangent line vector gridline tangent line vector.On the earth, the longitude and latitude of any point M is , crossing M point meridian circle in the tangent line vector terrestrial coordinate system internal coordinate at M point place is , crossing M point gridline in the tangent line vector terrestrial coordinate system internal coordinate at M point place is , then the angle of grid benchmark and geographic reference can be obtained for

（1）

According to the characteristic of Gauss projection, ellipsoid gridline is straight line on polar region Gauss projection drawing, great circle route is almost projected into grid loxodromic line, when carrier navigates by water along great circle route in polar region, the information resolved under the model be conducive to navigation personnel navigate by water monitoring and navigation paint calculation.

2 one kinds of inertial navigation system polar navigation parameter calculation methods

The invention provides inertial navigation system polar navigation parameter calculation method, based on the above ellipsoid grid heading reference built, the method is studied.Owing to only constructing new heading reference, velocity calculated under the location compute of inertial navigation system, navigational coordinate system, position angle resolve, solving of attitude etc. does not all change, and only need set up grid course on the original basis of resolving equation of inertial navigation and grid velocity resolves equation.

The present invention redefines heading reference, relatively manages benchmark have rotated on local level due to grid benchmark angle, utilizes this relation can obtain the grid course of carrier for

（2）

Grid course field of definition be .

Navigational coordinate system (p system) have rotated position angle relative to geographic coordinate system (g system) in local level , Grid Coordinate System ties up in local level relative to geographic coordinate and have rotated angle , then navigational coordinate system ties up in local level relative to grid coordinate and have rotated angle + , the rotation relationship matrix that navigation coordinate is tied to Grid Coordinate System is

（3）

Utilize this rotation relationship matrix, by speed under navigational coordinate system ( ) be converted into grid east orientation speed with grid north orientation speed

（4）

Do not consider vertical channel, namely

（5）

Known through above-mentioned analysis and formula (1), (2), (5), the method does not change inertial navigation system hardware configuration, original navigational parameter resolve in module add the inventive method resolve module, resolve grid course and grid velocity, calculate simple, therefore facilitate and directly apply in existing inertial navigation system, and the method both can export geographical course originally, velocity information, can export again be applicable to polar navigation grid course, velocity information.Based on ellipsoid grid inertial navigation system polar navigation method as shown in Figure 2.The method is applied widely, can be used for the inertial navigation system that various polar region can normally work, as free azimuth inertial navigation system, orientation of vacillating inertial navigation system, gyrobearing inertial navigation system and strapdown inertial navitation system (SINS) etc., also this navigational parameter calculation method can be inserted integrated navigation system and resolve in module.The advantage of the method at the polar navigation aspect of performance of raising inertial navigation system is discussed below for orientation inertial navigation system of vacillating:

From formula (2), grid course error is

（6）

Wherein , for geographical course error, carrying out quiet pedestal error analysis to orientation inertial navigation system of vacillating can obtain, geographical course error amplitude with relevant, with latitude raise course error become rapidly large, grid heading system error with irrelevant, but error slowly increases in time, and removing concussion property error can obtain

（7）

for north gyro constant value drift, for sky is to gyroscope constant value drift.Therefore, in polar region, under identical starting condition, in certain hour, grid course precision is better than geographical course precision.

From formula (5), grid velocity error is

（8）

, for x-axis velocity error under navigational coordinate system and y-axis velocity error, and geographical velocity error is

（9）

Carry out quiet pedestal error analysis to orientation inertial navigation system of vacillating can obtain, relevant, raise with latitude and become rapidly large, irrelevant, but error slowly increases in time, and removing concussion property error can obtain

（10）

The value that this increases item in polar region is very little, less to grid velocity error effect under moving base condition.Therefore, in polar region, under identical starting condition, grid velocity precision is better than geographical velocity accuracy.

Analyze for the precision of orientation inertial navigation system to invention itself of vacillating above, but application of the present invention is not limited to orientation inertial navigation system of vacillating.

Embodiment

In order to compare inertial navigation system grid course, velocity error and geographical course, velocity error, analyze under the following conditions:

(1) inertial navigation system is orientation inertial navigation system of vacillating;

(2) bearer rate is , initial latitude is 88 ° of N, and initial longitude is 120 °;

(3) gyroscope constant value drift is 0.001 °/h, and random drift is 0.001 °/h; Accelerometer constant value zero is 10 partially ^-5g, stochastic error is 10 ^-5g;

(4) initial error of inertial navigation navigation information is: horizontal attitude error is 10 〞, and azimuthal error is 20 〞, and site error is 10m, and horizontal velocity error is 0.05m/s;

(5) simulation time is 72h.

Geographical course error and grid course error emulates comparative graph and geographic north emulates comparative graph respectively as shown in accompanying drawing 3,4 to velocity error and grid north orientation velocity error.

As can be seen here: within one period of long period, grid course, velocity accuracy are better than geographical course, velocity accuracy, and verify that the method is more obvious higher than the polar region advantage of 80 ° at latitude through inventor.But grid heading system error introduces the item increased in time simultaneously, grid course is slowly increased in time, need to carry out correction of timing to grid course.Method of the present invention may be used for the flight guidance of the carriers such as polar region aircraft, naval vessel.

The above is preferred embodiment of the present invention, but the present invention should not be confined to the content disclosed in this embodiment and accompanying drawing.The equivalence completed under not departing from spirit disclosed in this invention so every or amendment, all fall into the scope of protection of the invention.

Claims (1)

1. an inertial navigation system polar region navigation parameter calculation method, it comprises the foundation of ellipsoid grid heading reference model, and ellipsoid grid heading reference model comprises following three aspects: (1) ellipsoid gridline defines: be parallel to the elliptical area outline line that meridian plane cutting earth's spheroid is formed; (2) definition of grid heading reference: in [0 °---90 ° of E] and [-90 ° of W---0 °] scope, grid north orientation is the direction pointing to latitude rising along gridline tangent line, in [90 ° of E---180 °] and [-90 ° of W----180 °] scope, grid north orientation is the direction pointing to latitude reduction along gridline line, " grid east; grid north, sky " coordinate system forms right hand rectangular coordinate system; (3) angle of grid heading reference and geographical heading reference: utilize vector quantities to amass operation relation, solves the angle of two benchmark by the angle solving meridian circle tangent line vector gridline tangent line vector;

It is characterized in that: it comprises the steps:

1st step: the latitude and longitude information resolved according to inertial navigation system navigation calculation module, inertial navigation computer resolves the angle of grid heading reference and geographical heading reference; Described grid heading reference and the angle of geographic reference wherein for geographic latitude, λ is geographic longitude;

2nd step: the angle determined according to the 1st step, inertial navigation computer resolves the rotation relationship matrix of navigational coordinate system and " grid east, grid north, sky " coordinate system; Its rotation relationship matrix is

$C_p^t=\left[\begin{array}{ccc}\cos (\mathrm{\α}+\mathrm{\β})& -\sin (\mathrm{\α}+\mathrm{\β})& 0\\ \sin (\mathrm{\α}+\mathrm{\β})& \cos (\mathrm{\α}+\mathrm{\β})& 0\\ 0& 0& 1\end{array}\right],$ P is navigational coordinate system, and t is " grid east, grid north, sky " coordinate system;

3rd step: the angle determined according to the 1st step, inertial navigation computer resolves grid course parameter, exports inertial navigation parameter display interface to; Described grid course parameter is K ^t=K ^g-β, wherein K ^tfor grid course, K ^gfor inertial navigation exports geographical course;

4th step: the rotation relationship matrix determined according to the 2nd step, inertial navigation computer resolves grid velocity parameter, and export inertial navigation parameter display interface to, grid velocity parameter is

$\left\{\begin{array}{c}{V}_E^t=\cos (\mathrm{\α}+\mathrm{\β})V_x^p-\sin (\mathrm{\α}+\mathrm{\β})V_y^p\\ V_N^t=\sin (\mathrm{\α}+\mathrm{\β})V_x^p+\cos (\mathrm{\α}+\mathrm{\β})V_y^p\end{array}\right.,$ Wherein for grid east orientation speed and for grid north orientation speed, α is the position angle of navigational coordinate system (p system) Z axis relative to geographic coordinate system (g system) Z axis, with be respectively speed under navigational coordinate system.