CN103399335B - A kind of mobile platform test macro - Google Patents

Abstract

The invention discloses a kind of mobile platform test macro and Error Compensation Algorithm, comprise monitoring base station and fixing movement station on a mobile platform, monitoring base station comprises the base station data radio station and differential GPS base station that are connected with supervisory control comuter, movement station comprises the Data acquisition system of FOG processing unit be connected with navigational computer, accelerometer data acquisition process unit and satellite positioning navigation unit, satellite positioning navigation unit is connected with navigation antenna, navigational computer connects movement station data radio station by communication controler, Data acquisition system of FOG processing unit is connected with navigational computer by IMU compensating unit with accelerometer data acquisition process unit.Mobile platform test macro and the Error Compensation Algorithm of the present invention's design solve in inertial navigation system, the error problem existed in the Project Realization process of the installation of inertance element, element and system.

Description

A kind of mobile platform test macro

Technical field

The invention belongs to a kind of inertial navigation test macro, be specifically related to a kind of mobile platform test macro and Error Compensation Algorithm.

Background technology

GPS has the advantages such as positioning precision is high, error does not accumulate in time, and uses Differential GPS Technology positioning precision to reach centimetre-sized.But GPS also also exist signal easily blocked or disturb, data updating rate is low, lack the shortcomings such as attitude information output; Comparatively speaking, inertial navigation system (INS) is a kind of completely autonomous navigational system, it has high data updating rate, and possess attitude information output, but due to the existence of gyro error drift, even if high-precision INS also faces the problem that error is constantly accumulated along with navigation time prolongation.Navigation accuracy is dispersed in time, can not work long hours separately, must constantly be calibrated.Owing to there is good complementary characteristic between GPS and INS, GPS/INS integrated navigation, can give full play to both respective advantages and learn from other's strong points to offset one's weaknesses.Utilize the long-time stability of GPS and moderate precision, the shortcoming that the error making up INS increases in time, utilize the short-term high precision of INS to make up GPS shortcoming such as lossing signal when being disturbed time error and increasing or block, and by the attitude information of inertial navigation system and angular velocity information, improve the directed maneuvering performance of GPS antenna; The high precision position information simultaneously provided continuously by GPS and velocity information, estimate and the site error of Correcting INS, velocity error and other error parameter of system, make whole integrated navigation system reach optimization, there is very high efficiency-cost ratio.In actual inertial navigation system, all inevitably there is error in the links in the Project Realization process of the installation of inertance element, element and system, and under the impact of these error components, the navigational parameter that inertial navigation system exports inevitably exists error.Initial error is the error caused by initial alignment, and Initial Alignment Error is one of main error source of inertial navigation system, and Initial Alignment Error not only shows in attitude angle the impact of systematic error, and performance is also in speed and location parameter.

Summary of the invention

In order to solve in inertial navigation system, the error problem existed in the Project Realization process of the installation of inertance element, element and system, the present invention devises a kind of mobile platform test macro and Error Compensation Algorithm.

A kind of mobile platform test macro, comprise monitoring base station and fixing movement station on a mobile platform, monitoring base station comprises the base station data radio station and differential GPS base station that are connected with supervisory control comuter, movement station comprises the Data acquisition system of FOG processing unit be connected with navigational computer, accelerometer data acquisition process unit and satellite positioning navigation unit, satellite positioning navigation unit is connected with navigation antenna, navigational computer connects movement station data radio station by communication controler, Data acquisition system of FOG processing unit is connected with navigational computer by IMU compensating unit with accelerometer data acquisition process unit.

Described mobile platform test macro, satellite positioning navigation unit receives GPS and GLONASS satellite ephemeris simultaneously, GPS and GLONASS dual system satellite antenna is separately fixed at mobile platform rear and front end.

Described mobile platform test macro, satellite positioning navigation unit and navigational computer are connected with data storage cell.

Described mobile platform test macro, mobile platform opertaing device is connected with sensor, and sensor is connected with communication controler by interface conversion circuit.

Described mobile platform test macro, Data acquisition system of FOG processing unit adopts three high-precision optical fibre gyros, accelerometer data acquisition process unit adopts three high-precision quartz accelerometers, and optical fibre gyro and quartz accelerometer are connected with temperature sensor respectively.

Its advantage is: mobile platform mobility measuring system is made up of data acquisition movement station and monitoring base station two parts, carries out real-time Data Transmission between movement station and base station by wireless digital broadcasting station, so that the real-time process of the test of testing crew controls.Movement station carries data storage card, can download afterwards carry out high-precision Data Post.Movement station hardware comprises Data acquisition system of FOG processing unit, quartz accelerometer data acquisition process unit, IMU compensating unit, navigational computer, satellite positioning navigation unit, data storage cell, communication controler, movement station data radio station, power supply unit nine ingredients.Movement station overall package, adopts air plug interface, waterproof and dampproof design.Adopt longevity of service, charge built-in power supply easily, can continuous working eight hours.

Data acquisition system of FOG processing unit adopts three axis angular rates of three high-precision optical fibre gyro sensitive carriers, in a pulsed fashion output angle incremental data, and processor is packed after reading the angle increment data of gyro, then sends IMU compensating unit to.In addition, every gyro inside comprises a temperature sensor, for the temperature of responsive gyro, and sends temperature data to IMU compensating unit, carries out temperature error compensation by IMU compensating unit according to the temperature of gyro to gyro data.

Accelerometer data acquisition process unit adopts three axis accelerometers of three high-precision quartz accelerometer sensitive carriers, the output of quartz accelerometer is current signal, after being converted to digital signal, be transferred to processor, after being packed by processor, send IMU compensating unit to.In addition, every accelerometer is installed a temperature sensor, for the temperature of sensitive accelerometers, and sent temperature data to IMU compensating unit, according to the temperature of accelerometer, temperature error compensation is carried out to acceleration by IMU compensating unit.

IMU compensating unit is used for three axis angular rates sent Data acquisition system of FOG processing unit, three axis accelerometers sent with gyro temperature, accelerometer data acquisition process unit and ACTE carry out various error compensation, then send three axis angular rates after compensation and three axis accelerometer data to navigation calculation unit, send data storage cell simultaneously to and store.

Navigational computer is used for carrier three axis angular rate that sends IMU compensating unit and three axis accelerometers and two GPS receives and processing unit sends GPS information to carry out integrated navigation and resolves, then send communication controler to, output to base station by data radio station.The data that navigational computer exports send data storage cell simultaneously to and store, to carry out off-line data processing.

Satellite positioning navigation unit can receive gps system and GLONASS system-satellite ephemeris simultaneously, and dual system works simultaneously, receives 2 aerial informations, and resolves according to double antenna information, exports geographical north course information.

Data storage cell, for storing the critical data of this equipment, comprising: IMU data, gps data etc.If the test figure obtained by data acquisition movement station all sends to monitoring base station in real time, data volume is very huge.This is because packet contains the three-phase acceleration information of the amount of GPS data of 20Hz, the 3 d pose data of 100Hz and 100Hz, then both data volumes are the former tens times.This transmission requirement cannot be met with the bandwidth of wireless digital broadcasting station general at present.Test data is stored in storage card by movement station, adopt frequency reducing mode simultaneously, by process of the test data by sending to base station again after data processing, to meet wireless digital broadcasting station bandwidth needs, base station testing crew is according to the validity of monitored results analytical test process, determine whether reform this test or adopt test figure, carrying out the mark of process of the test simultaneously.In the Data Post stage, the raw data such as GPS ephemeris stored by base station downloaded movement station and the original gyro of inertial navigation and acceleration information, and the raw GPS data that in binding tests process, base station stores, first carry out GPS Difference Calculation, comprehensive data analysis is carried out with differentiated GPS true value data and the original gyro of inertial navigation and acceleration information, according to the dynamic perfromance of carrier, adopt data fitting method, misdata larger for error in process of the test is weeded out, and continuous this process of iteration, till error meets system performance.The data fusion in Data Post stage can improve the results precision of position, speed, acceleration, attitude simultaneously, realizes high precision experimental test.

Communication controler for controlling data radio station, the navigation information that navigational computer is resolved according to agreement communication protocol real-time Transmission to base station.

Inertial navigation system error mainly comprises initial error, inertance element error, temperature error and the error of calculation.

Initial error is the error caused by initial alignment, and Initial Alignment Error is one of main error source of inertial navigation system, and Initial Alignment Error not only shows in attitude angle the impact of systematic error, and performance is also in speed and location parameter.Native system adopts dual system/double frequency/bis-gps antenna directional technology, at system electrification initial phase, can not only export accurate positional information, and can export course information accurately, for inertial navigation system provides accurate initial alignment information.

The inertance element error that inertance element itself and temperature cause is the principal element affecting inertial navigation system precision, for ensureing navigation accuracy, must reduce inertance element error.The approach reducing inertance element error mainly contains two kinds: hardware compensating, improves inertance element structural design and processing technology; Software compensation, tests inertance element, founding mathematical models, is improved the precision of inertance element by Error Compensation Technology.

In inertial navigation system, the constant multiplier of gyroscope and accelerometer, mounting shift angle, stochastic error and temperature variation, on the impact of navigation accuracy, can be equivalent to the impact of gyroscopic drift and accelerometer zero.Therefore, no matter in single inertial navigation system or integrated navigation system, all need founding mathematical models and adopt suitable computing method to carry out effective compensation to these two kinds of errors.

First temperature error compensation is carry out mathematical modeling to gyro and accelerometer, takes into full account that temperature is on gyro and the zero-bit of accelerometer and the impact of calibration factor.

The technological core of mobile platform mobility measuring system is the design of movement station main frame, main frame is wanted can gather high-precision attitude, speed, position data simultaneously, and we have employed the functional requirement that GPS/INS integrated navigation technology exploitation new algorithm achieves system.

An Error Compensation Algorithm for mobile platform test macro, described algorithm comprises the steps:

(1) set up inertial navigation error equation, and export latitude error with longitude error δ λ; Geographic coordinate system north orientation, east orientation and sensing geocentric velocity error delta V _n, δ V _ewith δ V _d; Attitude error angle Φ _n, Φ _eand Φ _d;

In formula, for true latitude; f _n, f _eand f _dbe respectively accelerometer to export; with for accelerometer zero error; R is earth radius; D is keel depth;

(2) GPS error equation is set up; And export the error of GPS latitude, longitude and height with east orientation, north orientation and sky to velocity error δ v _eGPS, δ v _nGPSwith δ v _uGPS;

The site error equation of GPS,

$\left\{\begin{array}{c}\mathrm{\δ}{\stackrel{\·}{L}}_{\mathrm{GPS}}=-\frac{\mathrm{\δ}{L}_{\mathrm{GPS}}}{{\mathrm{\τ}}_{\mathrm{LGPS}}}+w_{\mathrm{LGPS}}\\ \mathrm{\δ}{\stackrel{\·}{\mathrm{\λ}}}_{\mathrm{GPS}}=-\frac{\mathrm{\δ}{\mathrm{\λ}}_{\mathrm{GPS}}}{{\mathrm{\τ}}_{\mathrm{\λGPS}}}+w_{\mathrm{\λGPS}}\\ \mathrm{\δ}{\stackrel{\·}{h}}_{\mathrm{GPS}}=-\frac{\mathrm{\δ}{h}_{\mathrm{GPS}}}{{\mathrm{\τ}}_{\mathrm{hGPS}}}+w_{\mathrm{hGPS}}\end{array}\right.$

In formula, τ _lGPS, τ _{λ GPS}and τ _hGPSfor correlation time; w _lGPS, w _{λ GPS}and w _hGPSfor white-noise process.

The velocity error equation of GPS,

$\left\{\begin{array}{c}\mathrm{\δ}{\stackrel{\·}{v}}_{\mathrm{EGPS}}=-\frac{{\mathrm{\δv}}_{\mathrm{EGPS}}}{{\mathrm{\τ}}_{\mathrm{vEGPS}}}+w_{\mathrm{vEGPS}}\\ \mathrm{\δ}{\stackrel{\·}{v}}_{\mathrm{NGPS}}=-\frac{{\mathrm{\δv}}_{\mathrm{NGPS}}}{{\mathrm{\τ}}_{\mathrm{vNGPS}}}+w_{\mathrm{vNGPS}}\\ \mathrm{\δ}{\stackrel{\·}{v}}_{\mathrm{UGPS}}=-\frac{{\mathrm{\δv}}_{\mathrm{UGPS}}}{{\mathrm{\τ}}_{\mathrm{vUGPS}}}+w_{\mathrm{UGPS}}\end{array}\right.$

In formula, τ _vEGPS, τ _vNGPSand τ _vUGPSfor correlation time; w _vEGPS, w _vNGPSand w _uGPSfor white-noise process;

(3) set up INS system equation, export INS error; Comprise X _iNSsystem equation, W _iNSnoise battle array, G _iNSnoise allocation battle array and F _iNSsystem assignment battle array;

Chosen position error, velocity error, attitude error, gyroscopic drift and accelerometer error are as quantity of state, as follows:

State equation is

${\stackrel{\·}{X}}_{\mathrm{INS}}=F_{\mathrm{INS}}{X}_{\mathrm{INS}}+G_{\mathrm{INS}}{W}_{\mathrm{INS}}$

In formula, system noise is

W _INS＝[w _gxw _gyw _gzw _rxw _ryw _rzw _axw _ayw _az] ^T

The distribution battle array of system noise is

$G_{\mathrm{INS}}=\left[\begin{array}{ccc}{0}_{6\×3}& 0_{6\×3}& 0_{6\×3}\\ -C_b^n& 0_{3\×3}& 0_{3\×3}\\ 0_{3\×3}& 0_{3\×3}& 0_{3\×3}\\ 0_{3\×3}& I_{3\×3}& 0_{3\×3}\\ 0_{3\×3}& 0_{3\×3}& I_{3\×3}\end{array}\right]$

F _iNSnonzero element be

$F_{\mathrm{1,4}}=\frac{1}{R-d}$

F _3，6＝1 $F_{\mathrm{4,4}}=\frac{V_D}{R-d}$

$F_{\mathrm{4,6}}=\frac{V_N}{R-d}$ F _4，8＝-f _D

$F_{\mathrm{4,18}}=C_b^n\left(\mathrm{1,3}\right)$

$F_{\mathrm{4,18}}=C_b^n\left(\mathrm{1,3}\right)$

F _5，7＝f _D

F _5，9＝-F _N $F_{\mathrm{5,16}}=C_b^n\left(\mathrm{2,1}\right)$ $F_{\mathrm{5,17}}=C_b^n\left(\mathrm{2,2}\right)$

$F_{\mathrm{5,18}}=C_b^n\left(\mathrm{2,3}\right)$ $F_{\mathrm{6,4}}=-2\frac{V_N}{R-d}$

F _6，7＝-f _EF _6，8＝f _N

$F_{\mathrm{6,16}}=C_b^n\left(\mathrm{3,1}\right)$ $F_{\mathrm{6,17}}=C_b^n\left(\mathrm{3,2}\right)$ $F_{\mathrm{6,18}}=C_b^n\left(\mathrm{3,3}\right)$

$F_{\mathrm{7,5}}=\frac{1}{R-d}$

$F_{\mathrm{7,9}}=\frac{V_N}{R-d}$ $F_{\mathrm{7,10}}=-C_b^n\left(\mathrm{1,1}\right)$ $F_{\mathrm{7,11}}=-C_b^n\left(\mathrm{1,2}\right)$

$F_{\mathrm{7,12}}=-C_b^n\left(\mathrm{1,3}\right)$ $F_{\mathrm{7,13}}=-C_b^n\left(\mathrm{1,1}\right)$ $F_{\mathrm{7,14}}=-C_b^n\left(\mathrm{1,2}\right)$

$F_{\mathrm{7,15}}=-C_b^n\left(\mathrm{1,3}\right)$ $F_{\mathrm{8,4}}=-\frac{1}{R-d}$

$F_{\mathrm{8,10}}=-C_b^n\left(\mathrm{2,1}\right)$ $F_{\mathrm{8,11}}=-C_b^n\left(\mathrm{2,2}\right)$

$F_{\mathrm{8,12}}=-C_b^n\left(\mathrm{2,3}\right)$ $F_{8,13}=-C_b^n\left(\mathrm{2,1}\right)$ $F_{\mathrm{8,14}}=-C_b^n\left(\mathrm{2,2}\right)$

$F_{\mathrm{8,15}}=-C_b^n\left(\mathrm{2,3}\right)$

$F_{\mathrm{9,7}}=-\frac{V_N}{R-d}$ $F_{\mathrm{9,10}}=-C_b^n\left(\mathrm{3,1}\right)$

$F_{\mathrm{9,11}}=-C_b^n\left(\mathrm{3,2}\right)$ $F_{\mathrm{9,12}}=-C_b^n\left(\mathrm{3,3}\right)$ $F_{\mathrm{9,13}}=-C_b^n\left(\mathrm{3,1}\right)$

$F_{\mathrm{9,14}}=-C_b^n\left(\mathrm{3,2}\right)$ $F_{\mathrm{9,15}}=-C_b^n\left(\mathrm{3,3}\right)$ $F_{\mathrm{13,13}}=-\frac{1}{{\mathrm{\τ}}_g}$

$F_{\mathrm{14,14}}=-\frac{1}{{\mathrm{\τ}}_g}$ $F_{\mathrm{15,15}}=-\frac{1}{{\mathrm{\τ}}_g}$

(4) set up gps system equation, export GPS error; Comprise X _gPSsystem equation, F _gPSsystem assignment battle array, W _gPSnoise battle array;

Choose the longitude and latitude of GPS navigation system, sea level elevation and velocity error as quantity of state, as follows:

X _GPS＝[δL _GPSδλ _GPSδh _GPSδv _NGPSδv _EGPSδv _UGPS] ^T

The state equation of GPS is

${\stackrel{\·}{X}}_{\mathrm{GPS}}=F_{\mathrm{GPS}}{X}_{\mathrm{GPS}}+W_{\mathrm{GPS}}$

In formula,

$F_{\mathrm{GPS}}=\mathrm{diag}{[-\frac{1}{{\mathrm{\τ}}_{\mathrm{LGPS}}}-\frac{1}{{\mathrm{\τ}}_{\mathrm{\λGPS}}}-\frac{1}{{\mathrm{\τ}}_{\mathrm{hGPS}}}-\frac{1}{{\mathrm{\τ}}_{\mathrm{vNGPS}}}-\frac{1}{{\mathrm{\τ}}_{\mathrm{vEGPS}}}-\frac{1}{{\mathrm{\τ}}_{\mathrm{vUGPS}}}]}^T$

W _GPS＝[w _LGPSw _λGPSw _hGPSw _vNGPSw _vEGPSw _vUGPS] ^T

(5) measurement equation is set up;

Using step 3) inertial navigation and with step 4) GPS Position And Velocity difference as measurement amount, set up measurement equation; Determine the relation of measured value, error and actual value, the last result of actual value as system exported:

$Z_G=\left[\begin{array}{cc}{H}_4& H_{\mathrm{GPS}}\end{array}\right]\left[\begin{array}{c}{X}_{\mathrm{INS}}\\ X_{\mathrm{GPS}}\end{array}\right]+V_{\mathrm{GPS}}$

In formula,

H ₄＝[I _6×60 _6×12]

H _GPS＝[-I _6×6]

Native system adopts dual system/double frequency/bis-gps antenna directional technology, at system electrification initial phase, can not only export accurate positional information, and can export course information accurately, for inertial navigation system provides accurate initial alignment information.

Accompanying drawing explanation

Fig. 1 is present system structural representation;

Fig. 2 is the main error of inertial navigation system;

Fig. 3 is temperature error compensation block diagram;

Fig. 4 is course angle correlation curve;

Fig. 5 is angle of pitch correlation curve;

Fig. 6 is roll angle correlation curve;

Fig. 7 is mobile platform acceleration curve;

Fig. 8 is mobile platform braking procedure rate curve;

Fig. 9 is mobile platform braking procedure accelerating curve.

Embodiment

Below in conjunction with accompanying drawing, explanation is explained in detail to structure of the present invention, as shown in Figure 1, a kind of mobile platform test macro, comprise monitoring base station and fixing movement station on a mobile platform, monitoring base station comprises the base station data radio station and differential GPS base station that are connected with supervisory control comuter, movement station comprises the Data acquisition system of FOG processing unit be connected with navigational computer, accelerometer data acquisition process unit and satellite positioning navigation unit, satellite positioning navigation unit is connected with navigation antenna, navigational computer connects movement station data radio station by communication controler, Data acquisition system of FOG processing unit is connected with navigational computer by IMU compensating unit with accelerometer data acquisition process unit.Satellite positioning navigation unit receives GPS and GLONASS satellite ephemeris simultaneously, GPS and GLONASS dual system satellite antenna is separately fixed at mobile platform rear and front end.Satellite positioning navigation unit and navigational computer are connected with data storage cell.Mobile platform opertaing device is connected with sensor, and sensor is connected with communication controler by interface conversion circuit.Data acquisition system of FOG processing unit adopts three high-precision optical fibre gyros, and accelerometer data acquisition process unit adopts three high-precision quartz accelerometers, and optical fibre gyro and quartz accelerometer are connected with temperature sensor respectively.

Inertial navigation system error mainly comprises initial error, inertance element error, temperature error and the error of calculation, as shown in Figure 2.

An Error Compensation Algorithm for mobile platform test macro, described algorithm comprises the steps:

(1) inertial navigation error equation is set up: inertial navigation is the acceleration and the angular acceleration that utilize inertia device to measure carrier, sets up mechanical equation.Obtain the position of carrier, speed and attitude information by solving position equation, attitude equation, position rate equation, attitude rate equation and rate equation, the error equation of strapdown inertial navitation system (SINS) is as follows: export latitude error and longitude error; Geographic coordinate system north orientation, east orientation and sensing geocentric velocity error; Attitude error angle;

In formula, latitude and longitude error is respectively with δ λ; for true latitude; δ V _n, δ V _ewith δ V _dbe respectively geographic coordinate system north orientation, east orientation and sensing geocentric velocity error; Φ _n, Φ _eand Φ _dbe respectively attitude error angle; f _n, f _eand f _dbe respectively accelerometer to export; with for accelerometer zero error; R is earth radius; D is keel depth;

(2) set up GPS error equation, GPS error can be regarded as white noise or correlation time very short, the first-order Markov process that mean square deviation is very little; If carry out approximate fits by first-order Markov process, can be expressed as follows, comprise:

The site error equation of GPS, exports the error of GPS latitude, longitude and height; East orientation, north orientation and sky to velocity error;

$\left\{\begin{array}{c}\mathrm{\δ}{\stackrel{\·}{L}}_{\mathrm{GPS}}=-\frac{\mathrm{\δ}{L}_{\mathrm{GPS}}}{{\mathrm{\τ}}_{\mathrm{LGPS}}}+w_{\mathrm{LGPS}}\\ \mathrm{\δ}{\stackrel{\·}{\mathrm{\λ}}}_{\mathrm{GPS}}=-\frac{\mathrm{\δ}{\mathrm{\λ}}_{\mathrm{GPS}}}{{\mathrm{\τ}}_{\mathrm{\λGPS}}}+w_{\mathrm{\λGPS}}\\ \mathrm{\δ}{\stackrel{\·}{h}}_{\mathrm{GPS}}=-\frac{\mathrm{\δ}{h}_{\mathrm{GPS}}}{{\mathrm{\τ}}_{\mathrm{hGPS}}}+w_{\mathrm{hGPS}}\end{array}\right.$

In formula, with represent the error of latitude, longitude and height respectively; τ _lGPS, τ _{λ GPS}and τ _hGPSfor correlation time; w _lGPS, w _{λ GPS}and w _hGPSfor white-noise process;

The velocity error equation of GPS,

$\left\{\begin{array}{c}\mathrm{\δ}{\stackrel{\·}{v}}_{\mathrm{EGPS}}=-\frac{{\mathrm{\δv}}_{\mathrm{EGPS}}}{{\mathrm{\τ}}_{\mathrm{vEGPS}}}+w_{\mathrm{vEGPS}}\\ \mathrm{\δ}{\stackrel{\·}{v}}_{\mathrm{NGPS}}=-\frac{{\mathrm{\δv}}_{\mathrm{NGPS}}}{{\mathrm{\τ}}_{\mathrm{vNGPS}}}+w_{\mathrm{vNGPS}}\\ \mathrm{\δ}{\stackrel{\·}{v}}_{\mathrm{UGPS}}=-\frac{{\mathrm{\δv}}_{\mathrm{UGPS}}}{{\mathrm{\τ}}_{\mathrm{vUGPS}}}+w_{\mathrm{UGPS}}\end{array}\right.$

In formula, δ v _eGPS, δ v _nGPSwith δ v _uGPSrepresent respectively east orientation, north orientation and sky to velocity error; τ _vEGPS, τ _vNGPSand τ _vUGPSfor correlation time; w _vEGPS, w _vNGPSand w _uGPSfor white-noise process;

(3) set up INS system equation, export INS error; Comprise X _iNSsystem equation, W _iNSnoise battle array, G _iNSnoise allocation battle array and F _iNSsystem assignment battle array;

According to error features during strapdown inertial navitation system (SINS) long-term work, chosen position error, velocity error, attitude error, gyroscopic drift and accelerometer error are as quantity of state, as follows:

State equation is:

${\stackrel{\·}{X}}_{\mathrm{INS}}=F_{\mathrm{INS}}{X}_{\mathrm{INS}}+G_{\mathrm{INS}}{W}_{\mathrm{INS}}$

In formula, system noise is

W _INS＝[w _gxw _gyw _gzw _rxw _ryw _rzw _axw _ayw _az] ^T

The distribution battle array of system noise is

$G_{\mathrm{INS}}=\left[\begin{array}{ccc}{0}_{6\×3}& 0_{6\×3}& 0_{6\×3}\\ -C_b^n& 0_{3\×3}& 0_{3\×3}\\ 0_{3\×3}& 0_{3\×3}& 0_{3\×3}\\ 0_{3\×3}& I_{3\×3}& 0_{3\×3}\\ 0_{3\×3}& 0_{3\×3}& I_{3\×3}\end{array}\right]$

F _iNSnonzero element be

$F_{\mathrm{1,4}}=\frac{1}{R-d}$

F _3，6＝1 $F_{\mathrm{4,4}}=\frac{V_D}{R-d}$

$F_{\mathrm{4,6}}=\frac{V_N}{R-d}$ F _4，8＝-f _D

$F_{\mathrm{4,18}}=C_b^n\left(\mathrm{1,3}\right)$

$F_{\mathrm{4,18}}=C_b^n\left(\mathrm{1,3}\right)$

F _5，7＝f _D

F _5，9＝-F _N $F_{\mathrm{5,16}}=C_b^n\left(\mathrm{2,1}\right)$ $F_{\mathrm{5,17}}=C_b^n\left(\mathrm{2,2}\right)$

$F_{\mathrm{5,18}}=C_b^n\left(\mathrm{2,3}\right)$ $F_{\mathrm{6,4}}=-2\frac{V_N}{R-d}$

F _6，7＝-f _EF _6，8＝f _N

$F_{\mathrm{6,16}}=C_b^n\left(\mathrm{3,1}\right)$ $F_{\mathrm{6,17}}=C_b^n\left(\mathrm{3,2}\right)$ $F_{\mathrm{6,18}}=C_b^n\left(\mathrm{3,3}\right)$

$F_{\mathrm{7,5}}=\frac{1}{R-d}$

$F_{\mathrm{7,9}}=\frac{V_N}{R-d}$ $F_{\mathrm{7,10}}=-C_b^n\left(\mathrm{1,1}\right)$ $F_{\mathrm{7,11}}=-C_b^n\left(\mathrm{1,2}\right)$

$F_{\mathrm{7,12}}=-C_b^n\left(\mathrm{1,3}\right)$ $F_{\mathrm{7,13}}=-C_b^n\left(\mathrm{1,1}\right)$ $F_{\mathrm{7,14}}=-C_b^n\left(\mathrm{1,2}\right)$

$F_{\mathrm{7,15}}=-C_b^n\left(\mathrm{1,3}\right)$ $F_{\mathrm{8,4}}=-\frac{1}{R-d}$

$F_{\mathrm{8,10}}=-C_b^n\left(\mathrm{2,1}\right)$ $F_{\mathrm{8,11}}=-C_b^n\left(\mathrm{2,2}\right)$

$F_{\mathrm{8,12}}=-C_b^n\left(\mathrm{2,3}\right)$ $F_{\mathrm{8,13}}=-C_b^n\left(\mathrm{2,1}\right)$ $F_{\mathrm{8,14}}=-C_b^n\left(\mathrm{2,2}\right)$

$F_{\mathrm{8,15}}=-C_b^n\left(\mathrm{2,3}\right)$

$F_{\mathrm{9,7}}=-\frac{V_N}{R-d}$ $F_{\mathrm{9,10}}=-C_b^n\left(\mathrm{3,1}\right)$

$F_{\mathrm{9,11}}=-C_b^n\left(\mathrm{3,2}\right)$ $F_{\mathrm{9,12}}=-C_b^n\left(\mathrm{3,3}\right)$ $F_{\mathrm{9,13}}=-C_b^n\left(\mathrm{3,1}\right)$

$F_{\mathrm{9,14}}=-C_b^n\left(\mathrm{3,2}\right)$ $F_{\mathrm{9,15}}=-C_b^n\left(\mathrm{3,3}\right)$ $F_{\mathrm{13,13}}=-\frac{1}{{\mathrm{\τ}}_g}$

$F_{\mathrm{14,14}}=-\frac{1}{{\mathrm{\τ}}_g}$ $F_{\mathrm{15,15}}=-\frac{1}{{\mathrm{\τ}}_g}$

(4) set up gps system equation, export GPS error; Comprise X _gPSsystem equation, F _gPSsystem assignment battle array, W _gPSnoise battle array;

Choose the longitude and latitude of GPS navigation system, sea level elevation and velocity error as quantity of state, as follows;

X _GPS＝[δL _GPSδλ _GPSδh _GPSδv _NGPSδv _EGPSδv _UGPS] ^T

The state equation of GPS is

${\stackrel{\·}{X}}_{\mathrm{GPS}}=F_{\mathrm{GPS}}{X}_{\mathrm{GPS}}+W_{\mathrm{GPS}}$

In formula,

$F_{\mathrm{GPS}}=\mathrm{diag}{[-\frac{1}{{\mathrm{\τ}}_{\mathrm{LGPS}}}-\frac{1}{{\mathrm{\τ}}_{\mathrm{\λGPS}}}-\frac{1}{{\mathrm{\τ}}_{\mathrm{hGPS}}}-\frac{1}{{\mathrm{\τ}}_{\mathrm{vNGPS}}}-\frac{1}{{\mathrm{\τ}}_{\mathrm{vEGPS}}}-\frac{1}{{\mathrm{\τ}}_{\mathrm{UGPS}}}]}^T$

W _GPS＝[w _LGPSw _λGPSw _hGPSw _vNGPSw _vEGPSw _vUGPS] ^T

(5) measurement equation is set up; Using step 3) inertial navigation and with step 4) the Position And Velocity difference of GPS as measurement amount, set up measurement equation, determine the relation of measured value, error and actual value, the last result of actual value as system is exported:

$Z_G=\left[\begin{array}{cc}{H}_4& H_{\mathrm{GPS}}\end{array}\right]\left[\begin{array}{c}{X}_{\mathrm{INS}}\\ X_{\mathrm{GPS}}\end{array}\right]+V_{\mathrm{GPS}}$

In formula,

H ₄＝[I _6×60 _6×12]

H _GPS＝[-I _6×6]

Measurement equation establishes measured value, relation between error and actual value three, and by calculating the GPS, gyro and the accelerometer data that gather, the last result of actual value as system exported, output parameter is as follows:

Table 1 output parameter table;

First temperature error compensation is carry out mathematical modeling to gyro and accelerometer, takes into full account that temperature is on gyro and the zero-bit of accelerometer and the impact of calibration factor, compensates block diagram as shown in Figure 3.

The inertial navigation set of system comprises three duties: power-up initializing state, performance test state, high precision post processing difference state.

(1) power-up initializing state

After opening movement station power supply, movement station starts power supply, equipment self-inspection.Enter init state after self-inspection is normal, if self test failure, proceed to unit exception state.About 2 minutes power-up initializing time.During power-up initializing, gyroscope, accelerometer need about 1 minute ability steady operation, and navigational computer needs about 1 minute to carry out acquisition process to gyroscope and accelerometer data afterwards, carries out initial alignment; GPS needs about 1 point within 30 seconds, to carry out orientation and location.For the precision of guaranteed performance test, during initial alignment, require that mobile station apparatus keeps steady stability, not by the impact of external interference.

(2) performance test state

After movement station power-up initializing terminates, automatically enter performance test mode, now, movement station detects the position, speed, course, attitude parameter etc. of mobile platform in real time, is sent to base station by data radio station.After base station receives by data radio station the data that movement station sends, the state of the tested mobile platform of display and parameter in real time on supervisory control comuter.

(3) high precision post processing difference state

High precision post processing difference is used for downloading the raw data of movement station storage and the gps data of base station supervisory control comuter storage afterwards, carry out post processing difference, again gps data after difference is substituted in integrated navigation system algorithm and recalculate, obtain more high-precision test data.

With the sport car contrast test of laser inertial

Process of the test: mobile platform mobility measuring system and KJJ-33 laser inertial have carried out sport car contrast test.The course of KJJ-33 laser inertial and attitude accuracy are 0.01 degree.Test all times is approximately 40 minutes, about 20 kilometers of distance.Test the course of omnidistance sport car, attitude correlation curve as shown in Fig. 4, Fig. 5, Fig. 6.Carry out comparing, result is as follows afterwards:

(1) course difference standard deviation: 0.080224 degree;

(2) pitching difference standard deviation: 0.049675 degree;

(3) roll difference standard deviation: 0.038628 degree;

Compared with existing fiber gyro Position Fixing Navigation System, technical scheme of the present invention is more accurate, close to laser gyro attitude test precision.

Mobile platform actual load is tested

After system completes, carry out sufficient field trial, comprise the test of ground vehicle mobility and the test of above water platform mobility.Fig. 7, Fig. 8, Fig. 9 are the trial curve figure of mobile platform, and test findings shows, mobile platform mobility measuring system measuring accuracy is high, can meet the demand of mobility test completely.

The technical scheme that we adopt difference dual system (GPS+GLONASS) double antenna satellite positioning tech to be coupled with the closed-loop fiber optic gyroscope degree of depth is to realize our functional requirement.After system development completes, system mobile station main frame and SPAN-CPT and RT2502 have been carried out performance test test by us.

Table 2 movement station main frame and SPAN-CPT, RT2502 hardware contrast table,

Hardware names	Movement station main frame	SPAN	RT2502
				Gyro	0.5 (degree/hour)	0.75 (degree/hour)	2 (degree/hour)
Measurement of angle scope	±300°/s	±500°/s	±300°/s
				Add table	＜1.0mg	＜1.0mg	＜1.0mg
Acceleration analysis scope	±10g	±20g	±10g
				GPS	OEMV	OEMV	-

Table 3 movement station main frame and SPAN-CPT, RT2502 main performance index contrast table

Table 4 movement station main frame and SPAN real train test

Test event	Movement station main frame	SPAN
			Reversing test	Countless according to Divergent Phenomenon	There is data scatter phenomenon
Car body rotates a circle	Course deviation 0.1 degree	Course deviation 2 degree

Test illustrates:

1. the closed-loop fiber optic gyroscope of the built-in 0.5 °/h of movement station main frame, SPAN is the open loop gyro of built-in 0.75 °/h.Although the attitude accuracy that SPAN provides is higher, actual performance test performance is larger with movement station main frame gap.

2. movement station main frame adopts two GPS to utilize carrier wave measuring technique accurate Calculation course value, course precision is depending on base length between two GPS, under open environment, the base length of 2m can obtain the course precision of 0.15degree (RMS), and the longer precision of baseline is higher; In static state, just can make course by single pass-through GPS, and SPAN is single GPS, it cannot provide course value in static state.Time dynamic, movement station main frame also has GPS track angle to export, and accurately can provide drift angle.SPAN can not provide drift angle information.

3.RT2502 performance comparatively movement station main frame and SPAN low.

Contrast test shows, movement station host performance is top standard in the similar-type products of market.Aged device screening and structure destressing

Test macro will stand the environmental change of the working temperature of 0 DEG C ~+50 DEG C and the storage temperature of 0 DEG C ~+70 DEG C, and internal components, under temperature variation effect, can produce the effects such as stress relief in time, the measuring accuracy of influential system.For ensureing the reliability of system, native system whole devices used have all carried out strict burn-in screen.Buying is after device, and what first carry out is the burn-in screen of device, spends storage after 48 hours, slowly rise to high temperature 85 degree of storages 48 hours at low temperature-45, and then slowly reduces temperature to-45 degree storage 48 hours, repetitive cycling like this three times.

Equally, the stability of structural member to machining precision and structure of installing due to inertia device has higher requirements, for ensureing the measuring accuracy of inertia device, improve long-time stability, after structural member completion of processing, also will carry out high/low temperature storage, to discharge the stress of structural member, it is identical that method and above-mentioned device high/low temperature store screening technique.

After system installation testing completes, carrying out, the storage of complete machine high/low temperature is aging, after-40 degree are energized 24 hours continuously, appreciates 60 degree gradually, continuous energising 24 hours.Recover normal temperature afterwards, be energized more than 72 hours continuously at normal temperatures.

Technique scheme only embodies the optimal technical scheme of technical solution of the present invention, and those skilled in the art all embody principle of the present invention to some variations that wherein some part may be made, and belong within protection scope of the present invention.

Claims (1)

1. a mobile platform test macro, comprise monitoring base station and fixing movement station on a mobile platform, monitoring base station comprises the base station data radio station and differential GPS base station that are connected with supervisory control comuter, movement station comprises the Data acquisition system of FOG processing unit be connected with navigational computer, accelerometer data acquisition process unit and satellite positioning navigation unit, satellite positioning navigation unit is connected with navigation antenna, navigational computer connects movement station data radio station by communication controler, it is characterized in that, Data acquisition system of FOG processing unit is connected with navigational computer by IMU compensating unit with accelerometer data acquisition process unit, Data acquisition system of FOG processing unit adopts three optical fibre gyros, and accelerometer data acquisition process unit adopts three quartz accelerometers, and optical fibre gyro and quartz accelerometer are connected with temperature sensor respectively, satellite positioning navigation unit receives GPS and GLONASS satellite ephemeris simultaneously, GPS and GLONASS dual system satellite antenna is separately fixed at mobile platform rear and front end, and satellite positioning navigation unit and navigational computer are connected with data storage cell, mobile platform opertaing device is connected with sensor, and sensor is connected with communication controler by interface conversion circuit.