CN102117952B - Four-shaft stable framework for antenna and control method - Google Patents

Abstract

The invention relates to a four-shaft stable framework for an antenna and a control method. The stable framework comprises a framework part and a control case, wherein the framework part comprises a base, an azimuthal control frame, a pitching control frame and a rolling control frame; and control motors and detectors are respectively mounted on the base and each frame. Under the condition that the posture of a carrier is unknown, the posture of an antenna under a geographic coordinate system can be detected and is compared with the calculated posture of an antenna system under the geographic coordinate system to obtain a posture difference value; and the difference value is compensated by using a framework system to stabilize the antenna. With the globalization characteristics of ship navigation, the invention provides the four-shaft stable framework, which meets the global heading requirement and is more conductive to tracking objects in an all-day range.

Description

Four shaft stable framework for antennas and control method

Technical field

What the present invention relates to is a kind of satellite antenna systems stabilisation peculiar to vessel, the present invention also relates to a kind of control method of satellite antenna systems stabilisation peculiar to vessel.

Background technology

In recent years, development along with information technology, mobile vehicle obviously rises for the demand of information communication, produced thus the Related product of mobile vehicle satellite communication, different from land mobile reception systems stabilisation, ship operating envelope is wide, and therefore in order to satisfy the demand of boats and ships whole world navigation, existing diaxon frame antenna systems stabilisation can not satisfy the instructions for use in boats and ships.

Summary of the invention

The object of the present invention is to provide a kind of boats and ships four shaft stable framework for antennas to the satellite signal receiving requirement in whole world navigation process that satisfy.The present invention also aims to provide a kind of control method that reaches based on four shaft stable framework for antennas.

The object of the present invention is achieved like this:

Four shaft stable framework for antennas of the present invention comprise frame part and control cabinet; Frame section comprises pedestal, orientation controller chassis, pitch control subsystem frame, rolling controller chassis, and control motor and position detector all are housed on pedestal and each framework; The orientation control framework is installed on the pedestal, and drive motors and the angle detector of orientation controller chassis is housed in base interior; At the orientation control framework pitch control subsystem axle is installed, by the pitch control subsystem axle orientation control framework is connected with the pitch control subsystem framework, at pitch control subsystem axle two ends pitch axis drive motors and pitch axis angle detector are installed; Two frame planes of pitch control subsystem framework and orientation control framework are pitch control subsystem framework initial position when overlapping, and initial luffing angle is zero degree; The rolling controller chassis is installed in pitching frame, and it is vertical with the pitching frame that the rolling frame is installed initial position, is separately installed with up and down to drive motor and the angular transducer of rolling frame at the pitching frame; At the rolling control framework Inertial Measurement Unit for attitude detection is installed; In the rolling control framework, the polarizing control axle that is used for control antenna polarizing angle direction perpendicular to rolling control framework kinematic axis is installed, antenna is installed in polarizing control axle front end.

Four shaft stable framework for antennas of the present invention can also comprise:

Described orientation control framework is U-shaped, and described pitch control subsystem framework and rolling controller chassis are the O type.

Control method based on four shaft stable framework for antennas is:

Antenna is installed on four shaft stable framework for antennas, and described four shaft stable framework for antennas comprise frame part and the control cabinet of control system is housed; Frame section comprises pedestal, orientation controller chassis, pitch control subsystem frame, rolling controller chassis, and control motor and position detector all are housed on pedestal and each framework; The orientation control framework is installed on the pedestal, and drive motors and the angle detector of orientation controller chassis is housed in base interior; At the orientation control framework pitch control subsystem axle is installed, by the pitch control subsystem axle orientation control framework is connected with the pitch control subsystem framework, at pitch control subsystem axle two ends pitch axis drive motors and pitch axis angle detector are installed; Two frame planes of pitch control subsystem framework and orientation control framework are pitch control subsystem framework initial position when overlapping, and initial luffing angle is zero degree; The rolling controller chassis is installed in pitching frame, and it is vertical with the pitching frame that the rolling frame is installed initial position, is separately installed with up and down to drive motor and the angular transducer of rolling frame at the pitching frame; At the rolling control framework Inertial Measurement Unit for attitude detection is installed; In the rolling control framework, the polarizing control axle that is used for control antenna polarizing angle direction perpendicular to rolling control framework kinematic axis is installed, antenna is installed in polarizing control axle front end;

1, under the moored condition of harbour, start satellite antenna systems stabilisation peculiar to vessel after, system carries out the calculating of satellite antenna attitude angle according to selected satellite parametric reduction and geo-location parameter, obtains the angle of pitch and the azimuth of antenna;

2, judge that according to different luffing angle values the angle of pitch is whether 70 greater than degree; If the angle of pitch is less than 70 degree execution in step 3; Luffing angle is greater than 70 degree execution in step 4;

3, Inertial Measurement Unit as angle of pitch measured value, is defined as roll angle with vectorial FE around the angle value that vectorial OF rotates with vectorial OF and XOZ angulation;

Control system goes to the azimuth of calculating with the orientation frame of control framework structure, and the pitching frame goes to the angle of pitch that calculates, and rolling this moment frame keeps and pitching frame plumbness; At this moment, the angle of pitch that Inertial Measurement Unit detects should be the satellite angle of pitch that calculates, and roll angle should be zero degree;

When ship's navigation, because the impact of stormy waves, shaking in length and breadth appears in boats and ships, Inertial Measurement Unit will measure in length and breadth cradle angle, be respectively ε (t) and δ (t), because the motion of carrier, with so that antenna direction departs from original direction, control system will be controlled frame system according to the output information of inertia Inertial Measurement Unit and electronic compass, realizes the compensation of antenna direction offset direction; In the antenna frame structure, the controlled quentity controlled variable of each framework is according to formula

Calculate, the controlled quentity controlled variable that obtains is directly carried out the position servo of antenna frame, finishes compensation;

4, HG and ground angulation being defined as Inertial Measurement Unit angle of pitch measured value, will be the rolling angle of Inertial Measurement Unit around the viewpoint definition of HG rotation, utilize formula β=γ=∫ δ (t) dt and α=ω=∫ ε (t) dt+ θ _Pe, calculating each axis' control amount, the azimuth information of utilizing electronic compass to measure is carried out position servo to the orientation frame, and the control azimuth framework points to the satellite aximuth that calculates, and finally finishes for the compensation under the large pitching angle and controls.

Antenna stabilization system is the product that in the whole world navigation process requirement of satellite signal receiving is designed in order to satisfy boats and ships, has guaranteed the stable of satellite aerial directing in the motion process of ship's navigation.The present invention is from being fit to the demand in course, the boats and ships whole world, consider the different of different navigation latitudes and antenna pitching angle, design the antenna stabilization system framework of four axle construction and the control method of framework, solved the limitation that two kinds of cross-compound arrangements of AE, XY use.Control algolithm has designed two kinds of control procedures according to the different situations of when navigation angle of pitch, has brought into play the structural advantage of four axle frameworks, when satisfying whole world navigation to the demand of antenna stabilization system.

Description of drawings

The attitude angle of Fig. 1 synchronous satellite antenna in geographic coordinate system;

Fig. 2 four axle antenna frame structure schematic diagrames;

Four axle frame movement compensation principle figure during Fig. 3 flat attitude;

The angular relationship figure of each axle under Fig. 4 large pitching angle.

Embodiment

For example the present invention is done more detailed description below in conjunction with accompanying drawing:

In conjunction with Fig. 2, four shaft stable framework for antennas partly are comprised of frame part and control cabinet.Frame section can be divided into pedestal, orientation controller chassis (housing) 4, pitch control subsystem frame (center) 2, rolling controller chassis (inside casing) more than 7 parts, and control motor and position detector all are housed on pedestal and each framework.The orientation control framework is installed on the pedestal, and drive motors 10 and the angle detector 11 of orientation controller chassis is housed in base interior.The orientation controller chassis is put up U-shaped, at the orientation control framework pitch control subsystem axle is installed, by the pitch control subsystem axle orientation control framework and pitch control subsystem framework are linked together, at pitch control subsystem axle two ends pitch axis drive motors 3 and pitch axis angle detector 8 are installed.The pitch control subsystem framework is the O type framework of sealing, and definition pitch control subsystem framework is pitch control subsystem framework initial position when overlapping with two frame planes of orientation control framework, and initial luffing angle is zero degree.The rolling controller chassis has been installed in pitching frame, and the rolling controller chassis is O type frame, and it is vertical with the pitching frame that the rolling frame is installed initial position, is separately installed with up and down to drive motor 5 and the angular transducer of rolling frame at the pitching frame.At the rolling control framework Inertial Measurement Unit 1 for attitude detection is installed.In the rolling control framework of O type, perpendicular to rolling control framework kinematic axis, in O type framework face, polarizing control axle 6, polarizing control axis drive motor 9 for control antenna polarizing angle direction are installed, antenna just is installed in polarizing control axle front end.

Geostationary satellite overhead certain point in the equator of fixing a point, when carrier needs receiving satellite signal, need Calculation of Satellite in local geographic coordinate system the angle of pitch and the azimuth after adjust antenna direction and finish antenna alignment.The antenna attitude angle computational methods of carrier geographic location are as follows:

Fig. 1 is illustrated azimuth and the angle of pitch of the relative geographic coordinate system of satellite antenna.O represents ground ball center in the drawings, and N, S represent respectively south, the arctic of the earth, the position of satellite antenna on a point expression earth, and s represents the position of the satellite corresponding with a in the space, s ₁Line of expression so and the intersection point of the earth.Since the track of geostationary satellite be positioned at terrestrial equator directly over, so s ₁Go up under the line, b represented warp that a is ordered and the intersection point in equator, and ay, ap represent respectively arc as ₁, ab tangent line, wherein ap and os ₁Intersection point be c, the intersection point of ay and ob is d, the vertical od of ae is in e, cf is parallel to as and hands over ao in f.

So azimuth angle theta _He1Can be tried to achieve by following formula:

To the reference angle as the orientation, then get θ with north geographic pole this moment _HeFor: θ _He=180-θ _He1

Pitching angle theta _PeCalculating can be calculated by following formula:

When the azimuth of the relative geographic coordinate system of antenna and the angle of pitch are known, can derive antenna with respect to the angle of pitch and the azimuth of carrier according to the transformation relation between geographic coordinate system and carrier coordinate system, the real-time attitude of carrier is known in this requirement.The acquisition of attitude of carrier can be passed through three kinds of modes: the first, can provide by boats and ships self; The second, Inertial Measurement Unit is placed on the pedestal of antenna frame, directly measure attitude of carrier; The 3rd, extrapolate attitude of carrier by the angular transducer that directly is connected in the Inertial Measurement Unit Integration Framework system on the antenna.First method is installed boats and ships and is claimed, and affects the suitable dress of system; Second method since be not directly and antenna system be connected, detection and control precision all are affected; The third method need to be carried out a large amount of equation group computings in order to obtain attitude of carrier, and attitude matrix is difficult to find the solution.

Proposed based on the antenna stabilization control algolithm under the attitude of carrier unknown situation of attitude compensation between above reason this patent.The thought of algorithm is such, in the situation of attitude of carrier position, can detect the in the ground attitude under the coordinate system of antenna, the attitude of antenna system under geographic coordinate system that contrast calculates at this moment obtains pose difference, utilizes frame system, compensate this difference, realize antenna stabilization.Because the globalization characteristics of ship's navigation, this project proposes to satisfy four axle antenna stabilization frame structures of global course demand, more is conducive to follow the tracks of the target of whole day scope.

Characteristics according to four axle frame structures, the present invention has designed for the antenna stabilization framework control algolithm under the condition of different courses, algorithm can divide large pitching angle and two kinds of situations of flat attitude, than under the high latitude, satellite position is relatively low, the angle of pitch is less, so the AE structure relatively is fit to tracking servo.When ship's navigation than low latitudes the time, satellite position is higher, the angle of pitch is larger, needs work XY mode.Therefore this patent has designed based on the Inertial Measurement Unit attitude detection and has had the framework control algolithm of hysteretic characteristic.

The below introduces respectively two kinds of framework control algolithms in the situation:

The situation of ship's navigation location satellite luffing angle below 70 degree.

The satellite stable frame is abstracted into three dimensional vector diagram, and vectorial OF is the satellite antenna normal direction.Vector FE is for perpendicular to OF and be parallel to the vector of plane X OZ, and Inertial Measurement Unit is installed in the FEO of plane, and OF is Inertial Measurement Unit angle of pitch direction of measurement.

If be α with respect to the antenna base pitching frame luffing angle that makes progress, it is β that inside casing rotated the center angle, at this moment, because rotation causes Inertial Measurement Unit installed surface FEO run-off the straight, face after the inclination is F ' E ' O ', the definition of measuring the attitude of carrier roll angle by Inertial Measurement Unit as can be known, this moment, roll angle was plane K ' OF ' K and the dihedral angle that plane OF ' E ' becomes, and was designated as γ.Vectorial OF ' angle of pitch for antenna coordinate system is ω after rotating, and sets up variable α, β, and ω, the relation between the γ, can utilize following formula to calculate:

$\sin \mathrm{\&gamma;}=\frac{\sin \mathrm{\&alpha;}\sin \mathrm{\&beta;}}{\sqrt{{\sin }^2\mathrm{\&beta;}+{\mathrm{<figure-callout\; id="2"\; label="cos"\; filenames="HDA0000053283100000012.png"\; state="\{\{state\}\}">cos</figure-callout>}}^2\mathrm{\&alpha;}{\mathrm{<figure-callout\; id="2"\; label="cos"\; filenames="HDA0000053283100000012.png"\; state="\{\{state\}\}">cos</figure-callout>}}^2\mathrm{\&beta;}}}---\left(3\right)$

This moment, the calculating of ω can be obtained by following formula because vectorial OF turns to OF ', and the angle of pitch of antenna direction also has original β, becomes present ω:

sinω＝sinαcosβ (4)

The variation of the orientation angles that causes:

$\sin \mathrm{\&theta;}=\frac{\sin \mathrm{\&beta;}}{\sqrt{1-{\mathrm{<figure-callout\; id="2"\; label="cos"\; filenames="HDA0000053283100000012.png"\; state="\{\{state\}\}">cos</figure-callout>}}^2\mathrm{\&beta;}{\sin }^2\mathrm{\&beta;}}}---\left(5\right)$

As seen from Figure 4, vectorial OF course is 0 degree originally, and the angle of pitch is α, and vectorial FE is parallel to plane X OZ, at this moment, vectorial FE and OF is regarded as at rigidly connected two vectors of F point, and vectorial FE is perpendicular to vectorial OF, and vectorial FE is all the time in the FOZ of plane.Be in the situation of α at luffing angle, with O point position fixed point, behind the rotational angle β, the vectorial OF angle of pitch becomes ω to vectorial OF, vectorial FE and plane X OZ angulation γ in the FOZ of plane.When causing antenna frame system attitude to change owing to ship motion, Inertial Measurement Unit detects the rolling angle of δ and the pitching angle of ε.So, the finding the solution of method value of compensating that can be by finding the solution Simultaneous Equations namely solves α that the pitching angle framework for the rolling angle that produces compensation δ and ε need to move and the value of β.Here the value of α and β is the framework controlled quentity controlled variable.

Here two equations can solve α and β, simultaneously, because measured value is the relative value of relatively last compensation, therefore need to carries out integration to measure error and try to achieve total deviate and bring formula into as γ and ω and carry out finding the solution of α and β.That is:

γ＝∫δ(t)dt (6)

ω＝∫ε(t)dt+θ _pe (7)

In the following formula, δ (t) measures real-time roll angle for Inertial Measurement Unit, and ε (t) measures pitch angle and calculated value θ for the real-time inertial measuring unit _PeBetween difference, γ and ω are respectively roll angle and pitch angle with respect to the accumulated value of antenna frame system, θ _PeBe the angle of pitch calculated value of institute's tracking satellite in the boats and ships locality.

Since the variation of the antenna course angle direction that above-mentioned motion causes, according to can be calculated among Fig. 3:

$\sin \mathrm{\&theta;}=\frac{\sin \mathrm{\&beta;}}{\sqrt{1-{\mathrm{<figure-callout\; id="2"\; label="cos"\; filenames="HDA0000053283100000012.png"\; state="\{\{state\}\}">cos</figure-callout>}}^2\mathrm{\&beta;}{\sin }^2\mathrm{\&beta;}}}---\left(8\right)$

Find the solution for above-mentioned simultaneous equations, can obtain the value of corresponding α and β:

$\mathrm{\&alpha;}=\arcsin \left(\sqrt{{\sin }^2\mathrm{\&gamma;}+{\sin }^2\mathrm{\&omega;}-{\sin }^2\mathrm{\&omega;}{\sin }^2\mathrm{\&gamma;}}\right)---\left(9\right)$

$\mathrm{\&beta;}=\arccos \left(\frac{\sin \mathrm{\&omega;}}{\sqrt{{\sin }^2\mathrm{\&gamma;}+{\sin }^2\mathrm{\&omega;}-{\sin }^2\mathrm{\&omega;}{\sin }^2\mathrm{\&gamma;}}}\right)---\left(10\right)$

Again above α and β substitution azimuth are calculated formula, computer azimuth angle:

$\mathrm{\&theta;}=\arcsin \left(\frac{\sin \mathrm{\&beta;}}{\sqrt{1-{\mathrm{<figure-callout\; id="2"\; label="cos"\; filenames="HDA0000053283100000012.png"\; state="\{\{state\}\}">cos</figure-callout>}}^2\mathrm{\&beta;}{\sin }^2\mathrm{\&beta;}}}\right)---\left(11\right)$

The α that utilization calculates, β and θ angle, the compensation that course angle is changed is finished in control inside casing, center and housing motion.In conjunction with said process, finally finish the stable control of antenna system.

Next carry out the algorithm of ship's navigation when the satellite angle of pitch is regional more than 70 degree, when compensating work in this case, luffing angle changes the situation in 70 to 110 degree scopes.

Under the large pitching angle degree, because larger variation has occured the Inertial Measurement Unit benchmark, carry out inertial posture measuring according to original reference frame and can't satisfy the stable requirement of satellite antenna under the large pitching angle degree, therefore redefine measurement datum.In the situation that realizes satellite fix, XYZ coordinate is the antenna frame coordinate system, and definition X is the direction of housing normal.When the roll angle that is respectively the angle of pitch and the antenna attitude of antenna at the vectorial OF of being rigidly connected of initial position, FE, after antenna frame rotates the β angle, vector OF, FE turn to OF ', F ' E ', H ' F ' reverse extending and plane X OZ are met at a G ', cross straight line F ' G ' plane F ' G ' K, and F ' G ' K is vertical with F ' G ' with the intersection KG ' of plane X OZ.The roll angle that this hour angle γ causes vectorial FE to produce for rotation.See thus, after angle increases owing to adopt the method that redefines the attitude measurement benchmark so that roll angle and always angle can be directly motion by α and β compensate.Therefore, only α and β need to be recorded deviate according to Inertial Measurement Unit in this case compensates just passable.That is:

β＝γ＝∫δ(t)dt (12)

α＝ω＝∫ε(t)dt+θ _pe (13)

In the following formula, δ (t) measures real-time roll angle for Inertial Measurement Unit, and ε (t) measures pitch angle and calculated value θ for the real-time inertial measuring unit _PeBetween difference, γ and ω are respectively roll angle and pitch angle with respect to the accumulated value of antenna frame system, θ _PeBe the angle of pitch calculated value of institute's tracking satellite in the boats and ships locality.

Be that level has been finished in the situation of antenna location in initial condition, boats and ships enter operational configuration, and Inertial Measurement Unit detects antenna and shakes in length and breadth variation and can carry out according to the above results the control of antenna attitude, realizes antenna stabilization.Satellite antenna attitude stabilization system peculiar to vessel will according to the luffing angle of sensor measurement, be selected control algolithm.After algorithm is selected, the roll angle of measuring take Inertial Measurement Unit and pitch angle and course angle are as the control inputs amount, calculate corresponding α, β and θ, they distinguish azimuth controller chassis, angle of pitch controller chassis and the roll angle controller chassis of respective antenna frame system, with α, β and the θ value that calculates, give framework control servo-control system, finish the control to antenna attitude.

The control algolithm process is as follows:

1, under the moored condition of harbour, start satellite antenna systems stabilisation peculiar to vessel after, system carries out the calculating of satellite antenna attitude angle according to selected satellite parametric reduction and geo-location parameter, obtains the angle of pitch and the azimuth of antenna.

2, according to different luffing angle values, control program is divided into the angle of pitch spends two kinds of situations greater than 70 degree and the angle of pitch less than 70.

When 3, the angle of pitch was spent less than 70, with reference to Fig. 3, Inertial Measurement Unit as angle of pitch measured value, was defined as roll angle with vectorial FE around the angle value that vectorial OF rotates with vectorial OF and XOZ angulation.

4, control system goes to the azimuth of calculating with the orientation frame of control framework structure, and the pitching frame goes to the angle of pitch that calculates, and rolling this moment frame keeps and pitching frame plumbness.At this moment, the angle of pitch that Inertial Measurement Unit detects should be the satellite angle of pitch that calculates, and roll angle should be zero degree.

5, when ship's navigation, because the impact of stormy waves, shaking in length and breadth appears in boats and ships, Inertial Measurement Unit will measure in length and breadth cradle angle, be respectively ε (t) and δ (t), because the motion of carrier, with so that antenna direction departs from original direction, control system will be controlled frame system according to the output information of inertia Inertial Measurement Unit and electronic compass, realizes the compensation of antenna direction offset direction.In the antenna frame structure, the controlled quentity controlled variable of each framework is calculated according to formula (9), (10), (11), and the controlled quentity controlled variable that obtains is directly carried out the position servo of antenna frame, finishes compensation.

6, when luffing angle was spent greater than 70, antenna frame entered another kind of control model, because the change of luffing angle is large, need to reset Inertial Measurement Unit for the definition of pitching and rolling, could adapt to new mode of operation.Contrast Fig. 4 is defined as Inertial Measurement Unit angle of pitch measured value with HG and ground angulation, will be the rolling angle of Inertial Measurement Unit around the viewpoint definition of HG rotation, and the define method of orientation angles is constant.Utilize formula (12) and (13), calculate each axis' control amount, the azimuth information of utilizing electronic compass to measure is carried out position servo to the orientation frame, and the control azimuth framework points to the satellite aximuth that calculates.Finally finish for the compensation under the large pitching angle and control.

Claims (1)

1. control method based on four shaft stable framework for antennas is characterized in that:

Antenna is installed on four shaft stable framework for antennas, and described four shaft stable framework for antennas comprise frame part and the control cabinet of control system is housed; Frame section comprises pedestal, orientation controller chassis, pitch control subsystem frame, rolling controller chassis, and control motor and position detector all are housed on pedestal and each framework; The orientation controller chassis is installed on the pedestal, and drive motors and the angle detector of orientation controller chassis is housed in base interior; At the orientation controller chassis pitch control subsystem axle is installed, by the pitch control subsystem axle orientation controller chassis is connected with the pitch control subsystem frame, at pitch control subsystem axle two ends pitch axis drive motors and pitch axis angle detector are installed; Two frame planes of pitch control subsystem frame and orientation controller chassis are pitch control subsystem frame initial position when overlapping, and initial luffing angle is zero degree; The rolling controller chassis is installed in the pitch control subsystem frame, and it is vertical with the pitch control subsystem frame that the rolling controller chassis is installed initial position, is separately installed with up and down to drive motor and the angular transducer of rolling controller chassis at the pitch control subsystem frame; At the rolling controller chassis Inertial Measurement Unit for attitude detection is installed; In the rolling controller chassis, the polarizing control axle that is used for control antenna polarizing angle direction perpendicular to rolling controller chassis kinematic axis is installed, antenna is installed in polarizing control axle front end;

(1), under the moored condition of harbour, start satellite antenna systems stabilisation peculiar to vessel after, system carries out the calculating of satellite antenna attitude angle according to selected satellite parametric reduction and geo-location parameter, obtains the angle of pitch and the azimuth of antenna;

(2), judge that according to different luffing angle values whether the angle of pitch is greater than 70 degree; If the angle of pitch is less than 70 degree execution in step (3); Luffing angle is greater than 70 degree execution in step (4);

(3), Inertial Measurement Unit as angle of pitch measured value, will be defined as roll angle around the angle value that satellite antenna normal direction vector OF rotates with satellite antenna normal direction vector OF and plane XOZ angulation perpendicular to satellite antenna normal direction vector OF and the vectorial FE that is parallel to plane X OZ;

Control system goes to the azimuth of calculating with the orientation controller chassis of control framework structure, and the pitch control subsystem frame goes to the angle of pitch that calculates, and rolling this moment controller chassis keeps and pitch control subsystem frame plumbness; At this moment, the angle of pitch that Inertial Measurement Unit detects should be the satellite angle of pitch that calculates, and roll angle should be zero degree;

When ship's navigation, because the impact of stormy waves, shaking in length and breadth appears in boats and ships, Inertial Measurement Unit will measure in length and breadth cradle angle, be respectively ε (t) and δ (t), because the motion of carrier, with so that antenna direction departs from original direction, control system will be controlled frame system according to the output information of Inertial Measurement Unit and electronic compass, realizes the compensation of antenna direction offset direction; In the antenna frame structure, the controlled quentity controlled variable of each framework is according to formula

$\mathrm{\&beta;}=\arccos \left(\frac{\sin \mathrm{\&omega;}}{\sqrt{\mathrm{si}{n}^2\mathrm{\&gamma;}+\mathrm{si}{n}^2\mathrm{\&omega;}-\mathrm{si}{n}^2\mathrm{\&omega;si}{n}^2\mathrm{\&gamma;}}}\right)\&CenterDot;$ $\mathrm{\&theta;}=\arcsin \left(\frac{\sin \mathrm{\&beta;}}{\sqrt{1-\mathrm{co}{s}^2\mathrm{\&beta;si}{n}^2\mathrm{\&beta;}}}\right)$ Calculate, the controlled quentity controlled variable that obtains is directly carried out the position servo of antenna frame, finish compensation, γ and ω are respectively roll angle and pitch angle with respect to the accumulated value of antenna frame, and α, β and θ be azimuth controller chassis, angle of pitch controller chassis and the rolling controller chassis of respective antenna framework respectively;

(4), HG and ground angulation are defined as Inertial Measurement Unit angle of pitch measured value, will be the rolling angle of Inertial Measurement Unit around the viewpoint definition of HG rotation, utilize formula β=γ=∫ δ (t) dt and α=ω=∫ ε (t) dt+ θ _Pe, calculate each axis' control amount, θ _PeBe the angle of pitch calculated value of institute's tracking satellite in the boats and ships locality; The azimuth information of utilizing electronic compass to measure is carried out position servo to the orientation controller chassis, and the control azimuth framework points to the satellite aximuth that calculates, and finally finishes for the compensation under the large pitching angle and controls.

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