CN104697485B - Single-axis accelerometer based attitude measurement system and attitude measurement method thereof - Google Patents

Abstract

The invention relates to a single-axis accelerometer and three-axis magnetic field sensor based attitude measurement system and an attitude measurement method thereof. The system includes: an accelerometer, a three-axis magnetic field sensor, a GNSS module and a data processing module. The accelerometer is a Z axial direction single-axis accelerometer in orthogonal arrangement with a forward shaft and used for measuring gravitational acceleration component so as to obtain the triangle relationship between a ground carrier's roll angle and pitch angle. The data processing module is used for acquiring geomagnetic field model, geomagnetic inclination information and magnetic declination information according to a position information look-up table, and combining the triangle relationship between the ground carrier's roll angle and pitch angle and the three component arrays of a geomagnetic field under a carrier coordinate system to finally work out a course angle, the pitch angle and the roll angle. The new attitude measurement method provided by the invention can realize exact calculation of the carrier attitude angle under a carrier stationary or low speed moving state, can reduce a measurement amount, and avoids introduction of more measurement noise.

Description

Attitude measurement system based on single-axis acceleration sensors and its attitude measurement method

Technical field

The present invention relates to attitude of carrier e measurement technology, it is based on single-axis acceleration sensors and three-axle magnetic field particularly to a kind of The attitude measurement system of sensor and its attitude measurement method, be particularly suited for satellite quiet in all letter, the low speed of rapid deployment Degree motion（Speed per hour is less than 20km）The fields such as Vehicular satellite communication in moving communication.

Background technology

Satellite communication due to wide coverage, the stable feature of signal quality, can fix for ground, ground moving, boat Empty and maritime affairs user provides seamless communication service.Sent out by radio administration of the Ministry of Industry and Information Technology within 2013 according to China Cloth《It is set using mobile platform earth station administration Tentative Measures in fixed-satellite service communication network》（Hereinafter referred to as《Method》） Regulation, " mobile platform earth station refers to using fixed-satellite service C frequency range or Ku frequency range, be arranged on motor vehicles, train, ship, The earth station of radio communication on the moveable platforms such as airborne vehicle, can be carried out in movement or under halted state with satellite.Move Moving platform earth station can be divided into vehicle-mounted, boat-carrying, airborne, can the type such as moving type or portable earth station ".《Method》It further provides that " error in pointing that mobile platform earth station points to target satellite antenna main lobe axle should be less than 0.2 degree.At work, once pointing to The antenna main lobe axis error of target satellite is more than 0.5 degree it should be automatically stopped the transmitting of all signals in 100 milliseconds, until by mistake Difference is recovered to during less than 0.2 degree, can continue transmission signal.”

One typical mobile platform earth station at least should include：Antenna subsystem, communication subsystem, control subsystem, Power subsystem.Wherein, control the function of subsystem to essentially consist in and realize terminal attitude measurement and antenna sensing holding,《Method》 Specific requirement is proposed to the control accuracy controlling subsystem.For mobile platform earth station, generally require outfit strapdown The survey appearance system of formula, GNSS module and satellite beacon receiver.The survey appearance system of strapdown can measure the mobile platform earth The angle of pitch, roll angle and the magnetic azimuth stood, GNSS module can record geographical position and the height above sea level of mobile platform earth station Degree, in conjunction with the locus of telecommunication satellite, controls subsystem can calculate mobile platform earth station communication antenna in itself axle Orientation shaft angle, pitching shaft angle and the polarization shaft angle fastened；Satellite beacon receiver can receive the beacon letter of communication satellite broadcasting Number, the level value of beacon signal is the important references accurately to satelloid for the communication antenna, can pass through the fine tuning mobile platform earth The orientation shaft angle stood and pitching shaft angle are searching for the beacon level value of maximum.

With scientific and technical continuous development, more the occurring in of allocation plan of acceleration transducer and magnetic field sensor The fixed platform earth station of low cost is surveyed in appearance system.Similar survey appearance module common at present is at least equipped with two axle acceleration sensings Device and triaxial magnetic field sensor.Common double-axel acceleration sensor adopts X-Y type allocation plan, that is,：X-axis and carrier advance side To coincidence, Y-axis is pointed on the right side of carrier direction of advance, it is ensured that X-Y type acceleration passes in the whole process determining attitude of carrier Sensor remains static, and direct measurement goes out roll angle and the angle of pitch of carrier, then by the measurement of triaxial magnetic field sensor Data, calculates magnetic heading angle.During such survey appearance module work, less forward acceleration will cause larger Elevation angle error, for example：1m·s^-2Forward acceleration will lead to about 5.7 ° of pitching angle errors, and then reduce roll angular measurement essence Degree, finally largely effects on the precision of magnetic heading angular measurement.Meanwhile, two axle acceleration sensors introduce measurement noise twice, meeting Certain impact is brought to the certainty of measurement at inclination angle.

Content of the invention

It is an object of the present invention to provide a kind of attitude measurement based on single-axis acceleration sensors and triaxial magnetic field sensor System and its attitude measurement method are it is adaptable to fixed platform and mobile platform earth station.

Find through analysis, ground carrier occurs acceleration and deceleration motion brief acceleration to act directly on carrier advance shaft, will not The Z axis of impact and advance shaft quadrature arrangement are to the measurement of acceleration transducer.But the impact due to earth rotation, motion carrier is also To be acted on by Corioli's acceleration.The calculating of Corioli's acceleration is suitably simplified, the acquiescence earth is around the rotating speed of the axis of rotation Invariable, then the size of Corioli's acceleration is linear with carrier movement speed, and direction is constituted with bearer rate, the earth's axis Plane is orthogonal.

A kind of attitude measurement system based on single-axis acceleration sensors that the present invention provides, this system includes：Acceleration Sensor, triaxial magnetic field sensor, GNSS module data processing module；It is characterized in that,

Described acceleration transducer is to single-axis acceleration sensors with the Z axis of advance shaft quadrature arrangement；For measuring Gravitational acceleration component, obtains the roll angle of ground carrier and the triangle relation of the angle of pitch；

Described triaxial magnetic field sensor, for measuring three component arrays in earth's magnetic field under carrier coordinate system；

Described GNSS module, for measuring geographical position and height above sea level；

Described data processing module, obtains earth's magnetic field mould, geomagnetic inclination information and ground for tabling look-up according to positional information Three of earth's magnetic field under magnetic biasing angle information, the roll angle of combined ground carrier and the triangle relation of the angle of pitch and carrier coordinate system Component arrays finally calculate course angle, the angle of pitch and roll angle.

Described triaxial magnetic field sensor is fluxgate sensor or magnetoresistive transducer.

The position of described acceleration transducer and triaxial magnetic field sensor meets in the following manner：The x of triaxial magnetic field sensor Axle and the carrier longitudinal axis overlap, and positive direction and carrier direction of advance overlap, and y-axis and carrier transverse axis overlap, and positive direction is pointed to and carried The right side of body direction of advance；Z-axis and x, y constitute right-handed coordinate system；The z-axis positive direction of acceleration transducer and three-axle magnetic field sensing The z-axis forward direction of device is parallel.

Described data processing module is single-chip microcomputer, MCU or CPU.

The application is using the single-axis acceleration sensors parallel with ground carrier orientation rotation axle and triaxial magnetic field sensor Composition measurement sensor, wherein, single-axis acceleration sensors measure gravitational acceleration component, can obtain the roll of ground carrier Angle and the triangle relation of the angle of pitch, but can not uniquely determine carrier roll angle and the angle of pitch；Triaxial magnetic field sensor measurement ground Three components under body coordinate system for the magnetic field, can list three equations related with attitude of carrier angle it is contemplated that the phase of equation Closing property is it is impossible to independently calculate carrier magnetic heading angle, roll angle and the angle of pitch.Therefore, resolve attitude of carrier angle to reach Purpose, the present invention proposes a kind of utilization single-axis acceleration sensors and the attitude measurement new method of triaxial magnetic field sensor, the party Method can realize the accurate resolving at attitude of carrier angle under carrier stationary or low mobility state.

Another object of the present invention is to providing a kind of attitude measurement method based on single-axis acceleration sensors, the method Described in acceleration transducer be to single-axis acceleration sensors with the Z axis of advance shaft quadrature arrangement；Described method is concrete Comprise the following steps：

Step 1）Single-axis acceleration sensors measurement acceleration of gravity component upwards in carrier coordinate system Z axis, obtains ground The roll angle of face carrier and the triangle relation of the angle of pitch；

Step 2）The orthogonal work of three axles of magnetic field sensor, the earth's magnetic field three-component array in test carrier coordinate system；

Step 3）GNSS module is used for providing geographical location information and the elevation information of carrier；

Step 4）Data processing module is tabled look-up according to positional information and is obtained earth's magnetic field mould, geomagnetic inclination information and geomagnetic declination Three component battle arrays in earth's magnetic field under information, the roll angle of combined ground carrier and the triangle relation of the angle of pitch and carrier coordinate system Row finally calculate course angle, the angle of pitch and roll angle.

Described step 1）Acceleration transducer output measurement signal be digital signal or analogue signal, this analogue signal It is digital signal by AD conversion.

Described step 1）The output valve of Z-direction acceleration transducer be by acceleration of gravityCarrier movement cause from Heart acceleration α, Coriolis' acceleration α_cProjection components composition；

A）For the carrier being still in earth surface, α and α_cTwo perseverances are 0；

B）When carrier has motion, wherein,The centrifugation that the acceleration being caused by centrifugal force and earth rotation cause adds Speed forms, and takes earth mean radiuss to be 6371.004km, carrier movement speed is less than 40m s^-1When, carrier movement causes Centrifugal acceleration α be less than 2.51 × 10^-4m·s^-2；Taking earth rotation speed permanent is 7.29 × 10^-5rad·s^-1, then section's formula Acceleration alpha_cLess than 5.8 × sin ω × 10^-4m·s^-2, ω is the folder of earth rotation angle direction vector carrier movement velocity Angle；

ω is taken to be 90 °, then the component of acceleration maximum projecting in carrier coordinate system Z-direction is less than 5.8 × cos (B_e)×10^-4m·s^-2, B_eThe latitude information being located for carrier；

Carrier speed per hour be less than 150km when, centrifugal acceleration α that carrier movement causes withRatio be about 2.6 × 10^-5, Coriolis' acceleration withRatio be about 5.9 × 10^-5, then, during actual attitude measurement, two above accelerates Degree component is ignored；I.e. for motion the speed per hour not higher than carrier of 150km, during actual attitude measurement, can be right Two above component of acceleration is not considered.

According to the space-invariance of vector, acceleration of gravity vector after attitude matrix conversion, set up by following formula：

$\left[\begin{array}{ccc}\cos \mathrm{\θ}\cos \mathrm{\ψ}& \cos \mathrm{\θ}\sin \mathrm{\ψ}& -\sin \mathrm{\θ}\\ -\cos \mathrm{\γ}\sin \mathrm{\ψ}+\sin \mathrm{\γ}\sin \mathrm{\θ}\cos \mathrm{\ψ}& \cos \mathrm{\γ}\cos \mathrm{\ψ}+\sin \mathrm{\γ}\sin \mathrm{\θ}\sin \mathrm{\ψ}& \sin \mathrm{\γ}\cos \mathrm{\θ}\\ \sin \mathrm{\γ}\sin \mathrm{\ψ}+\cos \mathrm{\γ}\sin \mathrm{\θ}\cos \mathrm{\ψ}& -\sin \mathrm{\γ}\cos \mathrm{\ψ}+\cos \mathrm{\γ}\sin \mathrm{\θ}\sin \mathrm{\ψ}& \cos \mathrm{\γ}\cos \mathrm{\θ}\end{array}\right]\left[\begin{array}{c}{x}_{g0}\\ y_{g0}\\ z_{g0}\end{array}\right]=\left[\begin{array}{c}{x}_{g3}\\ y_{g3}\\ z_{g3}\end{array}\right]---\left(1\right)$

（1）In formula, ψ is carrier magnetic heading angle, and span is [0 °, 360 °], and θ is the carrier angle of pitch, and span is （-90°,90°）, γ is carrier roll angle, and span is（-90°,90°）；

Defining attitude of carrier [ψ, θ, γ] and being equal to during [0,0,0] attitude is original state, [x_g0, y_g0, z_g0]^TIt is acceleration Gravitational acceleration component array under carrier original state for the sensor；[x_g3, y_g3, z_g3]^TIt is in [ψ, θ, γ] attitude for carrier The gravitational acceleration component array of brief acceleration sensor measurement；

[x_g0, y_g0, z_g0]^TApproximately use [0,0, g₀]^TReplace, g₀Related with carrier height above sea level, residing geographic latitude, it takes Value is with reference to high-precision spheric harmonic function model；

Then further abbreviation（1）Formula obtains the cosine relation of carrier roll angle and the angle of pitch：

$\cos \mathrm{\γ}\cos \mathrm{\θ}=\frac{z_{g3}}{z_{g0}}---\left(2\right).$

Magnetic field sensor three axle is made to constitute right hand rhombic system, described step 2）Earth's magnetic field three-component array should be earth's magnetic field Component arrays under right hand rhombic system；

According to the space-invariance of vector, geomagnetic fieldvector after attitude matrix changes, set up by following formula

$\left[\begin{array}{ccc}\cos \mathrm{\θ}\cos \mathrm{\ψ}& \cos \mathrm{\θ}\sin \mathrm{\ψ}& -\sin \mathrm{\θ}\\ -\cos \mathrm{\γ}\sin \mathrm{\ψ}+\sin \mathrm{\γ}\sin \mathrm{\θ}\cos \mathrm{\ψ}& \cos \mathrm{\γ}\cos \mathrm{\ψ}+\sin \mathrm{\γ}\sin \mathrm{\θ}\sin \mathrm{\ψ}& \sin \mathrm{\γ}\cos \mathrm{\θ}\\ \sin \mathrm{\γ}\sin \mathrm{\ψ}+\cos \mathrm{\γ}\sin \mathrm{\θ}\cos \mathrm{\ψ}& -\sin \mathrm{\γ}\cos \mathrm{\ψ}+\cos \mathrm{\γ}\sin \mathrm{\θ}\sin \mathrm{\ψ}& \cos \mathrm{\γ}\cos \mathrm{\θ}\end{array}\right]\left[\begin{array}{c}{x}_{m0}\\ y_{m0}\\ z_{m0}\end{array}\right]=\left[\begin{array}{c}{x}_{m3}\\ y_{m3}\\ z_{m3}\end{array}\right]---\left(3\right)$

Formula（3）In, ψ is carrier magnetic heading angle, and span is [0 °, 360 °], and θ is the carrier angle of pitch, and span is （-90°,90°）, γ is carrier roll angle, and span is（-90°,90°）；Define attitude of carrier [ψ, θ, γ] be equal to [0,0, 0] it is original state during attitude, [x_m0, y_m0, z_m0]^TIt is geomagnetic field component array under carrier original state for the magnetometer, [x_m3, y_m3, z_m3]^TFor the geomagnetic field component array when carrier is in [ψ, θ, γ] attitude for the magnetometer.

Described data processing module according to positional information to earth's magnetic field factor database interpolation table obtain geomagnetic inclination I and Geomagnetic declination information α：

$\left[\begin{array}{ccc}\cos I& 0& -\sin I\\ 0& 1& 0\\ \sin I& 0& \cos I\end{array}\right]\left[\begin{array}{c}M\\ 0\\ 0\end{array}\right]=\left[\begin{array}{c}{x}_{m0}\\ y_{m0}\\ z_{m0}\end{array}\right]---\left(4\right)$

Formula（4）In, M is the mould in earth's magnetic field, and I is the magnetic dip angle in earth's magnetic field；The numerical value of M and I can come from high accuracy earth magnetism Field model.

Described step 4）By formula（2）、（3）With（4）Resolve and obtain the magnetic heading angle of carrier, the angle of pitch, roll angle, then to magnetic Course angle carries out declination compensation, obtains yaw angle ψ_N：

ψ_N=ψ-α （5）.

It is an advantage of the current invention that present applicant proposes a kind of Z axis are to acceleration transducer and X-Y-Z three-dimensional magnetic field sensing The survey appearance system and method that device combines, not only can reduce by a measurement amount, it is to avoid the introducing of more measurement noises, improve The angle measurement accuracy of attitude measurement module under quiescent conditions, can also improve the dynamic adaptable of module, be applied to low-speed motion Mobile platform earth station attitude measurement and control area, and reduce the number of axle of acceleration transducer configuration, reduce hardware cost.

Brief description

Fig. 1 is the schematic diagram of single-axis acceleration sensors, magnetic sensor and carrier coordinate system.

Fig. 2 is the schematic diagram of a typical attitude measurement module.

Fig. 3 is geographic coordinate system, the schematic diagram of earth's magnetic field coordinate system.

Specific embodiment

For making the object, technical solutions and advantages of the present invention become more apparent, below in conjunction with specific embodiment, and reference Accompanying drawing, the present invention is described in further detail.

Be given first and calculate the coordinate system used and angle definition.

1）Geographic coordinate system：As shown in figure 3, with carrier center of gravity O as initial point, N axle is positive to point to geographic north, and E axle forward direction refers to To geographical east, D axle is perpendicularly oriented to the earth's core, constitutes an orthogonal right-handed system with N axle and E axle.

O is geographic coordinate system and earth's magnetic field coordinate origin, and geographic coordinate system ONED is the referential of attitude angle definition, Under simple Gravity Models, gravitational field points to the earth's core, the D overlapping of axles of gravity field vector g and geographic coordinate system.

Wherein, i axle is positive points to magnetic north pole, and the positive magnetic that points to of j axle is eastern, and the D overlapping of axles of k axle and geographic coordinate system is square To sensing the earth's core.Earth's magnetic field coordinate system Oijk and the anglec of rotation relation of geographic coordinate system ONED one fixation of presence, this rotation Corner is exactly magnetic declination α.In Fig. 3, I is magnetic dip angle, and B is geomagnetic fieldvector.

2）Earth's magnetic field coordinate system：Initial point and geographic coordinate system initial point O overlap, and i axle is positive to point to magnetic north pole, and j axle forward direction refers to To magnetic east, the D overlapping of axles of k axle and geographic coordinate system, positive sensing the earth's core, constitute an orthogonal right-handed system with i axle and j axle.Ground There is a fixing anglec of rotation relation in magnetic system of coordinates and geographic coordinate system, this anglec of rotation is exactly geomagnetic declination α.Ground magnetic biasing Angle α, geomagnetic inclination I and the three elements of geomagnetic total field B composition description geomagnetic fieldvector, geomagnetic fieldvector and earth's magnetic field coordinate system Relation is shown in Fig. 3.

3）Carrier coordinate system：As shown in figure 1, O_mThe initial point of body coordinate system, the initial point that triaxial magnetic field sensor disposes.x_mFor The magnetic field sensor measurement axis of direction of advance；y_mFor the magnetic field sensor measurement axis on the right side of direction of advance；z_mFor magnetic field sensor Vertical axle, with x_mAxle and y_mAxle constitutes right-handed system.

O_gFor body coordinate origin, the initial point that acceierometer sensor is installed, in theory and O_mOverlap, carrier is thought of as One rigid body, in actual installation, two points can be misaligned.z_gAxle is the vertical axle of acceleration transducer, and z_mAxle is parallel.θ is The carrier angle of pitch, γ is carrier roll angle.

Three coordinate axess and carrier are fixed together, and x-axis and the carrier longitudinal axis overlap, and positive direction points to direction of advance, and y-axis is just To pointing on the right side of carrier direction of advance, z-axis and x-axis, y-axis constitute orthogonal right-handed system.

4）Attitude angle is used for describing the relation of carrier coordinate system and geographic coordinate system, is determined by three below Eulerian angles Justice：

Magnetic yaw angle ψ：The projection in the horizontal plane of the carrier longitudinal axis and the angle of magnetic north, carrier right avertence is navigated as just；

Pitching angle theta：The carrier longitudinal axis and the angle of horizontal plane, carrier header is just upwards.

Roll angle γ：Just switch to around carrier longitudinal axis dextrorotation, otherwise be negative.Select carrier transverse axis with local level angle be It is the reference zero of roll angle during zero degree.

Based on above-mentioned definition, as shown in Fig. 2 GNSS receiver provides the positional information of the high form of longitude and latitude of carrier, wherein, L_eFor carrier longitude, B_eFor carrier latitude, H_eFor carrier height above sea level.z_gFor single-axis acceleration sensors test volume, x_m, y_mAnd z_mIt is Triaxial magnetic field sensor test volume, ψ_NIt is carrier heading, span is [0 °, 360 °], and θ is the carrier angle of pitch, value model Enclosing is（-90°,90°）, γ is carrier roll angle, and span is（-90°,90°）.

The single-axis acceleration sensors that the present embodiment proposes and triaxial magnetic field sensor measurement attitude new method specifically include Following steps：

Step 1）Acceleration transducer measurement acceleration of gravity constitutes cross section normal in the carrier longitudinal axis shown in Fig. 1 and transverse axis On component, described acceleration transducer measurement signal can be digital signal or analogue signal.

Described acceleration transducer can be single-axis acceleration sensors, double-axel acceleration sensor, and 3-axis acceleration passes Sensor；Described acceleration transducer should provide the Z-direction component signal of acceleration of gravity；Described measurement signal, if analogue signal, Should be digital signal by AD conversion.

The output valve of Z-direction acceleration transducer is that the centrifugal acceleration that causes of acceleration of gravity, carrier movement, section's formula accelerate Degree composition.

According to the space-invariance of vector, acceleration of gravity vector after attitude matrix conversion, set up by following formula：

$\left[\begin{array}{ccc}\cos \mathrm{\θ}\cos \mathrm{\ψ}& \cos \mathrm{\θ}\sin \mathrm{\ψ}& -\sin \mathrm{\θ}\\ -\cos \mathrm{\γ}\sin \mathrm{\ψ}+\sin \mathrm{\γ}\sin \mathrm{\θ}\cos \mathrm{\ψ}& \cos \mathrm{\γ}\cos \mathrm{\ψ}+\sin \mathrm{\γ}\sin \mathrm{\θ}\sin \mathrm{\ψ}& \sin \mathrm{\γ}\cos \mathrm{\θ}\\ \sin \mathrm{\γ}\sin \mathrm{\ψ}+\cos \mathrm{\γ}\sin \mathrm{\θ}\cos \mathrm{\ψ}& -\sin \mathrm{\γ}\cos \mathrm{\ψ}+\cos \mathrm{\γ}\sin \mathrm{\θ}\sin \mathrm{\ψ}& \cos \mathrm{\γ}\cos \mathrm{\θ}\end{array}\right]\left[\begin{array}{c}{x}_{g0}\\ y_{g0}\\ z_{g0}\end{array}\right]=\left[\begin{array}{c}{x}_{g3}\\ y_{g3}\\ z_{g3}\end{array}\right]---\left(1\right)$

（1）In formula, ψ is carrier magnetic heading angle, and span is [0 °, 360 °], and θ is the carrier angle of pitch, and span is （-90°,90°）, γ is carrier roll angle, and span is（-90°,90°）.Define attitude of carrier [ψ, θ, γ] be equal to [0,0, 0] it is original state during attitude, [x_g0, y_g0, z_g0]^TIt is gravitational acceleration component under carrier original state for the acceleration transducer Array；[x_g3, y_g3, z_g3]^TIt is in the gravitational acceleration component battle array of [ψ, θ, γ] attitude brief acceleration sensor measurement for carrier Row.

[x_g0, y_g0, z_g0]^T[0,0, g can approximately be used₀]^TReplace, g₀It is related with carrier height above sea level, residing geographic latitude, Value may be referred to high-precision spheric harmonic function model.

Abbreviation further（1）Formula can obtain the cosine relation of carrier roll angle and the angle of pitch：

$\cos \mathrm{\γ}\cos \mathrm{\θ}=\frac{z_{g3}}{z_{g0}}---\left(2\right).$

Step 2）Magnetic field sensor should be triaxial magnetic field sensor, and three axles answer orthogonal work, in test carrier coordinate system Earth's magnetic field three-component array.

Described triaxial magnetic field sensor can also be able to be magnetoresistive transducer for fluxgate sensor；Described three axles are just handed over Work can make magnetic field sensor three axle constitute right hand rhombic system it is also possible to constitute left hand rhombic system；Described earth's magnetic field three-component battle array Row should be earth's magnetic field in right hand rhombic system（North-east-ground）Under component arrays.

According to the space-invariance of vector, geomagnetic fieldvector after attitude matrix changes, set up by following formula

$\left[\begin{array}{ccc}\cos \mathrm{\θ}\cos \mathrm{\ψ}& \cos \mathrm{\θ}\sin \mathrm{\ψ}& -\sin \mathrm{\θ}\\ -\cos \mathrm{\γ}\sin \mathrm{\ψ}+\sin \mathrm{\γ}\sin \mathrm{\θ}\cos \mathrm{\ψ}& \cos \mathrm{\γ}\cos \mathrm{\ψ}+\sin \mathrm{\γ}\sin \mathrm{\θ}\sin \mathrm{\ψ}& \sin \mathrm{\γ}\cos \mathrm{\θ}\\ \sin \mathrm{\γ}\sin \mathrm{\ψ}+\cos \mathrm{\γ}\sin \mathrm{\θ}\cos \mathrm{\ψ}& -\sin \mathrm{\γ}\cos \mathrm{\ψ}+\cos \mathrm{\γ}\sin \mathrm{\θ}\sin \mathrm{\ψ}& \cos \mathrm{\γ}\cos \mathrm{\θ}\end{array}\right]\left[\begin{array}{c}{x}_{m0}\\ y_{m0}\\ z_{m0}\end{array}\right]=\left[\begin{array}{c}{x}_{m3}\\ y_{m3}\\ z_{m3}\end{array}\right]---\left(3\right)$

Formula（3）In, ψ is carrier magnetic heading angle, and span is [0 °, 360 °], and θ is the carrier angle of pitch, and span is （-90°,90°）, γ is carrier roll angle, and span is（-90°,90°）.Define attitude of carrier [ψ, θ, γ] be equal to [0,0, 0] it is original state during attitude, [x_m0, y_m0, z_m0]^TIt is geomagnetic field component array under carrier original state for the magnetometer, [x_m3, y_m3, z_m3]^TFor the geomagnetic field component array when carrier is in [ψ, θ, γ] attitude for the magnetometer.

Step 3）GNSS module is used for providing geographical location information and the elevation information of carrier, and MCU is according to positional information pair Geomagnetic field elements data base's interpolation table obtains geomagnetic inclination and geomagnetic declination information.

Described GNSS module possesses the ability providing carrier geographical position and elevation information, and described MCU model is not limited to list Piece machine, it is possible to have the other kinds of CPU of MCU function.

$\left[\begin{array}{ccc}\cos I& 0& -\sin I\\ 0& 1& 0\\ \sin I& 0& \cos I\end{array}\right]\left[\begin{array}{c}M\\ 0\\ 0\end{array}\right]=\left[\begin{array}{c}{x}_{m0}\\ y_{m0}\\ z_{m0}\end{array}\right]---\left(4\right)$

Formula（4）In, M is the mould in earth's magnetic field, and I is the magnetic dip angle in earth's magnetic field.The numerical value of M and I can come from high accuracy earth magnetism Field model.

Step 4）The magnetic heading angle of carrier, the angle of pitch, roll angle are resolved according to algorithm.

Described algorithm is by formula（2）、（3）With（4）Composition, what algorithm resolving obtained is magnetic yaw angle, the angle of pitch, roll angle, Declination compensation is carried out to magnetic heading angle, yaw angle ψ can be obtained_N.

ψ_N=ψ-α （5）.

It should be noted last that, above example is only in order to illustrate technical scheme and unrestricted.Although ginseng According to embodiment, the present invention is described in detail, it will be understood by those within the art that, the technical side to the present invention Case is modified or equivalent, and without departure from the spirit and scope of technical solution of the present invention, it all should be covered in the present invention Right in the middle of.

Claims (10)

1. a kind of attitude measurement system based on single-axis acceleration sensors, this system includes：Acceleration transducer, three-axle magnetic field Sensor, GNSS module data processing module；It is characterized in that,

Described acceleration transducer is to single-axis acceleration sensors with the Z axis of advance shaft quadrature arrangement；For measuring gravity Component of acceleration, obtains the roll angle of ground carrier and the triangle relation of the angle of pitch；

Described triaxial magnetic field sensor, for measuring three component arrays in earth's magnetic field under carrier coordinate system；

Described GNSS module, for measuring geographical position and height above sea level；

Described data processing module, obtains earth's magnetic field mould, geomagnetic inclination information and ground magnetic biasing for tabling look-up according to positional information Three components in earth's magnetic field under angle information, the roll angle of combined ground carrier and the triangle relation of the angle of pitch and carrier coordinate system Array finally calculates course angle, the angle of pitch and roll angle.

2. attitude measurement system according to claim 1 is it is characterised in that described triaxial magnetic field sensor passes for fluxgate Sensor or magnetoresistive transducer.

3. attitude measurement system according to claim 1 is it is characterised in that described acceleration transducer and three-axle magnetic field pass The position of sensor meets in the following manner：The x-axis of triaxial magnetic field sensor and the carrier longitudinal axis overlap, and positive direction and carrier advance side To coincidence, y-axis and carrier transverse axis overlap, and positive direction points to the right side of carrier direction of advance；Z-axis and x, y constitute right-handed scale (R.H.scale) System；The z-axis positive direction of acceleration transducer is parallel with the z-axis forward direction of triaxial magnetic field sensor.

4. attitude measurement system according to claim 1 is it is characterised in that described data processing module is single-chip microcomputer, MCU Or CPU.

5. a kind of attitude measurement method based on single-axis acceleration sensors, the acceleration transducer described in the method be with front The Z axis entering axle quadrature arrangement are to single-axis acceleration sensors；Described method specifically includes following steps：

Step 1) single-axis acceleration sensors measurement acceleration of gravity in carrier coordinate system Z axis component upwards, obtain ground carry The roll angle of body and the triangle relation of the angle of pitch；

Step 2) magnetic field sensor the orthogonal work of three axles, the earth's magnetic field three-component array in test carrier coordinate system；

Step 3) GNSS module is used for providing geographical location information and the elevation information of carrier；

Step 4) data processing module tables look-up acquisition earth's magnetic field mould, geomagnetic inclination information and geomagnetic declination letter according to positional information Breath, three component arrays in earth's magnetic field under the roll angle of combined ground carrier and the triangle relation of the angle of pitch and carrier coordinate system Finally calculate course angle, the angle of pitch and roll angle.

6. attitude measurement method according to claim 5 is it is characterised in that described step 1) acceleration transducer output Measurement signal be digital signal or analogue signal, this analogue signal by AD conversion be digital signal.

7. the attitude measurement method according to claim 5 or 6 is it is characterised in that described step 1) Z-direction acceleration sensing The output valve of device is by acceleration of gravityCentrifugal acceleration a and Coriolis' acceleration a that carrier movement causes_cProjection components Composition；

According to the space-invariance of vector, acceleration of gravity vector after attitude matrix conversion, set up by following formula：

$\left[\begin{array}{ccc}\cos \mathrm{\θ}\cos \mathrm{\ψ}& \cos \mathrm{\θ}\sin \mathrm{\ψ}& -\sin \mathrm{\θ}\\ -\cos \mathrm{\γ}\sin \mathrm{\ψ}+\sin \mathrm{\γ}\sin \mathrm{\θ}\cos \mathrm{\ψ}& \cos \mathrm{\γ}\cos \mathrm{\ψ}+\sin \mathrm{\γ}\sin \mathrm{\θ}\sin \mathrm{\ψ}& \sin \mathrm{\γ}\cos \mathrm{\θ}\\ \sin \mathrm{\γ}\sin \mathrm{\ψ}+\cos \mathrm{\γ}\sin \mathrm{\θ}\cos \mathrm{\ψ}& -\sin \mathrm{\γ}\cos \mathrm{\ψ}+\cos \mathrm{\γ}\sin \mathrm{\θ}\sin \mathrm{\ψ}& \cos \mathrm{\γ}\cos \mathrm{\θ}\end{array}\right]\left[\begin{array}{c}{x}_{g0}\\ y_{g0}\\ z_{g0}\end{array}\right]=\left[\begin{array}{c}{x}_{g3}\\ y_{g3}\\ z_{g3}\end{array}\right]---\left(1\right)$

(1) in formula, ψ is carrier magnetic heading angle, and span is [0 °, 360 °], and θ is the carrier angle of pitch, span be (- 90 °, 90 °), γ is carrier roll angle, and span is (- 90 °, 90 °)；

Defining attitude of carrier [ψ, θ, γ] and being equal to during [0,0,0] attitude is original state, [x_g0,y_g0,z_g0]^TIt is acceleration transducer Gravitational acceleration component array under carrier original state；[x_g3,y_g3,z_g3]^TIt is in during [ψ, θ, γ] attitude for carrier and accelerate The gravitational acceleration component array of degree sensor measurement；

[x_g0,y_g0,z_g0]^TApproximately use [0,0, g₀]^TReplace, g₀Related with carrier height above sea level, residing geographic latitude, its value is joined Examine high-precision spheric harmonic function model；

Then abbreviation (1) formula obtains the cosine relation of carrier roll angle and the angle of pitch further：

$\cos \mathrm{\γ}cos\mathrm{\θ}=\frac{z_{g3}}{z_{g0}}---\left(2\right).$

8. attitude measurement method according to claim 5 is it is characterised in that make the magnetic field sensor three axle composition right hand orthogonal System, described step 2) earth's magnetic field three-component array should be component arrays under right hand rhombic system for the earth's magnetic field；

According to the space-invariance of vector, geomagnetic fieldvector after attitude matrix changes, set up by following formula：

$\left[\begin{array}{ccc}\cos \mathrm{\θ}\cos \mathrm{\ψ}& \cos \mathrm{\θ}\sin \mathrm{\ψ}& -\sin \mathrm{\θ}\\ -\cos \mathrm{\γ}\sin \mathrm{\ψ}+\sin \mathrm{\γ}\sin \mathrm{\θ}\cos \mathrm{\ψ}& \cos \mathrm{\γ}\cos \mathrm{\ψ}+\sin \mathrm{\γ}\sin \mathrm{\θ}\sin \mathrm{\ψ}& \sin \mathrm{\γ}\cos \mathrm{\θ}\\ \sin \mathrm{\γ}\sin \mathrm{\ψ}+\cos \mathrm{\γ}\sin \mathrm{\θ}\cos \mathrm{\ψ}& -\sin \mathrm{\γ}\cos \mathrm{\ψ}+\cos \mathrm{\γ}\sin \mathrm{\θ}\sin \mathrm{\ψ}& \cos \mathrm{\γ}\cos \mathrm{\θ}\end{array}\right]\left[\begin{array}{c}{x}_{m0}\\ y_{m0}\\ z_{m0}\end{array}\right]=\left[\begin{array}{c}{x}_{m3}\\ y_{m3}\\ z_{m3}\end{array}\right]---\left(3\right)$

In formula (3), ψ is carrier magnetic heading angle, and span is [0 °, 360 °], and θ is the carrier angle of pitch, span be (- 90 °, 90 °), γ is carrier roll angle, and span is (- 90 °, 90 °)；Define attitude of carrier [ψ, θ, γ] and be equal to [0,0,0] It is original state during attitude, [x_m0,y_m0,z_m0]^TIt is geomagnetic field component array under carrier original state for the magnetometer, [x_m3,y_m3, z_m3]^TFor the geomagnetic field component array when carrier is in [ψ, θ, γ] attitude for the magnetometer.

9. attitude measurement method according to claim 5 is it is characterised in that described data processing module is believed according to position Breath obtains geomagnetic inclination I and geomagnetic declination information α to earth's magnetic field factor database interpolation table：

$\left[\begin{array}{ccc}\cos I& 0& -\sin I\\ 0& 1& 0\\ \sin I& 0& \cos I\end{array}\right]\left[\begin{array}{c}M\\ 0\\ 0\end{array}\right]=\left[\begin{array}{c}{x}_{m0}\\ y_{m0}\\ z_{m0}\end{array}\right]---\left(4\right)$

In formula (4), M is the mould in earth's magnetic field, and I is the magnetic dip angle in earth's magnetic field；The numerical value of M and I can come from accurately magnetic field mould Type.

10. attitude measurement method according to claim 5 is it is characterised in that described step 4) resolve the magnetic obtaining carrier Course angle, the angle of pitch, roll angle, then declination compensation is carried out to magnetic heading angle, obtain yaw angle ψ_N：

ψ_N=ψ-α (5)；

Wherein, ψ is magnetic heading angle, and α is magnetic declination；ψ_NIt is the yaw angle with regard to geographical north.