CN117849736A

CN117849736A - Method and system for integrally calibrating and compensating microwave load surface-pose errors on orbit

Info

Publication number: CN117849736A
Application number: CN202311802750.6A
Authority: CN
Inventors: 胡华龙; 江世臣; 杨之浩; 信思博; 李�昊; 曾擎; 王田野
Original assignee: Shanghai Institute of Satellite Engineering
Current assignee: Shanghai Institute of Satellite Engineering
Priority date: 2023-12-25
Filing date: 2023-12-25
Publication date: 2024-04-09

Abstract

The invention provides a method and a system for integrally calibrating and compensating a microwave load shape surface-pose error on orbit, wherein the method comprises the following steps: step 1: establishing a satellite coordinate system of each reflecting surface on the ground through a coplanar laser target; step 2: calibrating coordinate values of the coding mark points and the common point conversion targets under a main and inverse design coordinate system on the ground, and the relation between the satellite coordinate systems of all the reflecting surfaces and the corresponding laser measurement coordinate systems; step 3: shooting the main and the counter simultaneously by using photogrammetry cameras at different positions during the track period, and resolving the three-dimensional coordinates of the single-point mark points on the main and the counter surfaces; step 4: the common point conversion target is utilized to realize the reference transmission of the laser measurement result of the coplanar laser target, and the pose of the reflecting surface is calculated under the main and inverse design coordinate system; step 5: and performing shape-face matching according to the three-dimensional coordinates of the main and inverse single-point mark points, solving an equivalent pose error introduced by deformation of the main and inverse shape faces, calculating a reflecting face pose adjustment compensation quantity according to a reflecting face pose calculation result, and performing reflecting face pose adjustment.

Description

Method and system for integrally calibrating and compensating microwave load surface-pose errors on orbit

Technical Field

The invention relates to the technical field of satellite microwave remote sensing, in particular to a method and a system for integrally calibrating and compensating a microwave load surface-pose error in an on-orbit manner; more particularly, it relates to a method and system for calibrating and adjusting and compensating the overall on-orbit error of the stationary orbit microwave load 'shape face-pose'.

Background

During the in-orbit working of the stationary orbit microwave detection satellite, the external heat flow environment is complex, and the large-scale reflection surface antenna carried by the stationary orbit microwave detection satellite can generate 'shape surface-pose' coupling thermal deformation due to severe temperature change, so that the beam pointing deflection, the gain reduction and the side lobe elevation are caused. Therefore, the integral on-orbit calibration of the 'shape face-pose' error of the reflecting face is required to be realized on the satellite, and the pose of the reflecting face is quickly adjusted and compensated according to the calibration result so as to correct the antenna pattern distortion and ensure the optimal on-orbit working performance of the static orbit microwave load.

Through the search of the prior art:

the non-patent literature 'data processing of antenna measurement and the prospect of real-time measurement' (see radio engineering, 1996, volume 26, 4) adopts a template method to measure the accuracy of the small antenna shape surface, and the accuracy reaches 0.2mm; application of electronic theodolite intersection measuring system in large-scale antenna precise installation measurement (see ocean survey, 2005, 25/1) adopts theodolite method to 600m ² The antenna performs deformation analysis, and the accuracy reaches 0.5mm. Since such conventional measuring methods require a lot of manual participation, the measuring process is complicated and the measuring efficiency is low, so that it is difficult to apply the method to the stationary track microwave load.

The non-patent literature 'application of high-precision digital photogrammetry technology in a 50m large-scale antenna' (see surveying and mapping engineering, 2007, 16 th volume and 1 phase) uses a photogrammetry method to carry out deformation analysis on the dense cloud 50m antenna, the measurement time is 1h, the data processing is 9h, and the precision reaches 0.4mm. The method is high in automation degree, but time is consumed for measuring and processing data, and the antenna is difficult to work in the measuring process, so that the method is difficult to apply to the stationary track microwave load.

The non-patent literature "holographic measurement method of surface accuracy of large-scale reflector antenna" (see electronic design engineering, 2018, volume 26, 1) describes holographic measurement method of reflector antenna, which uses fourier transform to determine amplitude-phase distribution of aperture surface field by measuring antenna amplitude and phase pattern, and further calculates antenna-shaped surface error. The method needs a proper high-frequency strong source (satellite source and radio source), so that the method can only measure under a specific pitch angle, and the problems that manual intervention is needed, and the measurement process and the antenna work cannot be compatible are also existed.

The non-patent literature 'rapid detection method and accuracy analysis of large antenna panel shape' (see photonics report, 2022, volume 51, 6) designs an antenna panel deformation measurement scheme based on a three-dimensional laser scanner, obtains 70m antenna panel deformation information, takes 1h for measuring and processing point cloud data, and has the accuracy of 0.3mm. Because the point cloud data measurement processing still needs a certain time, the method cannot adapt to the quasi-real-time requirements of the static track microwave load 'shape face-pose' error calibration and adjustment compensation, and the installation layout of the laser scanner near the feed source cannot be suitable for the static track microwave load.

Patent document CN114812523a (application number 202210383008.5) discloses a dual-reflecting-surface antenna pose analysis system, in which a laser scanner is applied to pose analysis of dual-reflecting-surface antenna assembly coaxiality, reflecting-surface relative distance, and the like. Compared with a photogrammetry, the antenna pose analysis system based on the laser measurement method is greatly simplified, the measurement speed is higher, but the installation layout of the laser scanner and the targets still needs to be further improved to adapt to the stationary track microwave load.

For the stationary orbit microwave load, the on-orbit deformation of the reflecting surface has the coupling characteristic of 'shape surface-pose', any single measuring means can not accurately trace the source, the measuring efficiency is lower, the measuring cost is higher, therefore, the integral on-orbit calibration of the error of the 'shape surface-pose' of the reflecting surface is realized by combining a photogrammetry and a laser measuring method, and the pose of the reflecting surface is adjusted and compensated according to the calibration result. Engineering experience has not been available in the past to combine the two.

Disclosure of Invention

Aiming at the defects in the prior art, the invention aims to provide a method and a system for integrally calibrating and compensating the microwave load surface-pose errors on orbit.

The invention provides a method for integrally calibrating and compensating a microwave load shape surface-pose error on-orbit, which comprises the following steps:

step S1: establishing a satellite coordinate system of each reflecting surface on the ground through a coplanar laser target, and using the satellite coordinate system as a reference coordinate system for adjusting the pose of the reflecting surface;

step S2: calibrating coordinate values of the coding mark points and the common point conversion targets under a main and inverse design coordinate system on the ground, and the relation between the satellite coordinate systems of all the reflecting surfaces and the corresponding laser measurement coordinate systems;

step S3: shooting the main reflecting surface simultaneously by using photogrammetry cameras at different positions during the track period, resolving the three-dimensional coordinates of the single-point mark points on the surface of the main reflecting surface, and converting the three-dimensional coordinates of all the single-point mark points into a main inverse design coordinate system through coding mark points;

step S4: measuring three-dimensional coordinates of a common point conversion target and a coplanar laser target by using a laser scanning measurement camera during the track period, realizing reference transmission of laser measurement results of the coplanar laser target by using the common point conversion target, unifying the laser measurement results into a main and inverse design coordinate system, and resolving the pose of the reflecting surface under the main and inverse design coordinate system;

Step S5: under a main and inverse design coordinate system, performing shape-face matching on the obtained three-dimensional coordinates of the single point mark points on the surface of the main reflecting surface, solving a main and inverse equivalent pose error introduced by the deformation of the main reflecting surface, calculating a reflecting surface pose adjustment compensation quantity by combining the reflecting surface pose and performing reflecting surface pose adjustment, so as to realize integral on-orbit calibration and adjustment compensation of the static track microwave load shape-pose error;

the reflecting surface satellite coordinate system is a coordinate system which is established by a coplanar laser target adhered to the reflecting surface and moves along with the reflecting surface, and is used for describing the pose change of the reflecting surface relative to a main reverse design coordinate system;

the main and inverse design coordinate system is characterized in that a coordinate origin is positioned at the geometrical vertex of the main reflecting surface of the three-reflecting-surface antenna, a z-axis is a focal axis of a paraboloid of revolution, the focal point of the main and inverse design coordinate system is pointed from the geometrical vertex of the paraboloid of revolution, and the main and inverse design coordinate system and the satellite platform are in an inclined installation relationship;

the laser measurement coordinate system is a distance-angle spherical coordinate system used for measuring angles and ranges of a laser scanning measurement camera.

Preferably, the step S1 employs:

a, B, C, D is the 4 coplanar laser targets on the reflecting surface, and the three-dimensional coordinates of the 4 coplanar laser targets measured by the laser scanning measurement camera are respectively A (x, y, z), B (x, y, z), C (x, y, z) and D (x, y, z); taking 4 coplanar target centers Q as the origin of a reflecting surface satellite coordinate system, and the following formula is as follows:

The corresponding unit direction vector of the satellite coordinate system triaxial under the laser measurement coordinate system is as follows:

wherein a, b and c are undetermined coefficients of plane equations of coplanar laser targets under a laser measurement coordinate system, and the method comprises the following steps ofFitting to obtain the final product.

Preferably, the step S2 employs:

the origin of the laser measurement coordinate system is recorded as J,the coordinate axis unit direction vector of the coordinate system is measured for the laser,θ, ψ are the satellite coordinate system around the laser measurement coordinate system>The Euler angle of shaft rotation, the rotation matrix R from the laser measurement coordinate system to the reflecting surface satellite coordinate system is obtained by 3-1-2 rotation sequence:

the pose of the satellite coordinate system relative to the laser measurement coordinate system is obtained by the method:

preferably, the step S3 employs:

step S3.1: simultaneously photographing the main reflecting surface by adopting 4 photogrammetry cameras to obtain 4 main reflecting surface shape images comprising photogrammetry mark points and a surface measurement reference ruler; the photogrammetry mark points comprise coding mark points and single-point mark points;

step S3.2: automatically identifying, extracting and positioning the coding mark points and the single-point mark points in the 4 pictures to obtain a coding value of each coding mark point, a central image plane coordinate of the coding point and a central image plane coordinate of the single-point mark point;

Step S3.3: a stereopair is built based on the main reflection surface-shaped images of adjacent shooting stations, a left image space coordinate system is used as a left image space auxiliary coordinate system, the three axes of a right image space auxiliary coordinate system and the three axes of the left image space auxiliary coordinate system are mutually parallel, and the relative orientation element (b) of the right image relative to the left image is obtained _v ，b _w ，ω ₂ ，κ ₂ )；

Wherein: (x) ₀ ，y ₀ F) is the internal azimuth element of the photo, the stereopair can be considered to have the same internal azimuth element, and the rotation matrix R is formed by the rotation angle of 3 degrees of the right photo relative to the left photoω ₂ ，k ₂ ) Composition;

step S3.4: the core line matching principle is utilized to match the same name point of the single point mark points, and the single point mark point p of the left photo is recorded ₁ The coordinates in the right shot image space coordinate system are (x' _p1 ，y′ _p1 ，z′ _p1 ) Left camera station S ₁ The coordinates in the right shot image space coordinate system are (x' _S1 ，y′ _S1 ，z′ _S1 ) From S ₁ 、p ₁ And S is ₂ The three points are coplanar, and the equation of the nuclear plane in the space coordinate system of the right photo image is obtained as follows:

the homonymy epipolar equation is thus:

respectively calculating the distance from each pixel of the right photo to the homonymous epipolar line, taking the minimum value to judge whether the distance is smaller than 1, and judging the distance to be the homonymous image point of the single-point mark point of the left photo if the distance is smaller than 1;

step S3.5: solving an image space auxiliary coordinate system coordinate initial value of a single point mark point corresponding to the same name image point of the stereopair;

Wherein: (X, Y, Z) is the initial value of the coordinates of the auxiliary coordinate system in the single-point mark point image space to be solved, (X) _S ，Y _S ，Z _S ) Spatially-assisted coordinate system coordinates for the camera image (a) ₁ ，a ₂ ，a ₃ ，…，c ₁ ，c ₂ ，c ₃ ) 9 parameters for composing the rotation matrix; the arrangement is thus possible:

if the n images contain the same single-point mark point, 2n linear equation sets can be listed to solve the initial coordinate values (X, Y, Z) of the auxiliary coordinate system of the single-point mark point image space;

step S3.6: the adjustment of the beam method takes a collineation conditional equation as a basic mathematical model, takes the coordinates of each outside-image azimuth element and the space auxiliary coordinate system of all single-point mark point images as unknowns, and realizes the optimal intersection of the same-name light rays through the rotation and translation of the beam in space;

step S3.7: the least square point fitting is developed for the three-dimensional coordinate measured value of the main and inverse coding mark points and the ground calibration theoretical value, so that the reference transmission from the measurement coordinate system to the main and inverse design coordinate system is realized, and the three-dimensional coordinates of the main and inverse single-point mark points in the main and inverse design coordinate system are determined;

wherein: lambda is the scale factor of the coefficient of the scale,to measure coordinate system to main counterCounting a rotation matrix of a coordinate system; and then determining a scaling factor according to the measuring length and the calibration length of the surface measuring standard ruler, and uniformly scaling the three-dimensional coordinates of all the single-point mark points to obtain a final measuring result.

Preferably, the step S4 employs:

step S4.1: measuring reference transmission;

note p= (P ₁ ，p ₂ ，…，p _n ) Sum q= (Q ₁ ，q ₂ ，…，q _n ) For the common point conversion target coordinate measurement value on a pair of back struts obtained by the first and second laser scanning measurement cameras, a singular value decomposition method is adopted to solve a rotation matrix between the first and second laser measurement coordinate systems and a common measurement coordinate systemThe transmission process of the measurement reference of the second laser measurement coordinate system and the first laser measurement coordinate system is as follows:

solving rotation matrix between laser measurement coordinate system one and main inverse design coordinate system through main inverse surface central region common point conversion target point position least square fittingThe laser measurement coordinate system one and the main reverse design coordinate system measurement reference transmission process is as follows:

step 4.2: respectively establishing a satellite coordinate system of each reflecting surface under a main and inverse design coordinate system to obtain the pose relation of the satellite coordinate system of each reflecting surface relative to the main and inverse design coordinate system, comprising the following steps: a pair of reversed pose: (Q' _F1 ，θ′ _F1 ，ψ′ _F1 ) And (3) carrying out secondary reverse posture: (Q' _F2 ，/>θ′ _F2 ，ψ′ _F2 ) Main and reverse pose: (Q' _F ，/>θ′ _F ，ψ′ _F )。

Preferably, the step S5 employs:

step 5.1: fitting a shape surface and obtaining an equivalent pose error;

after the main reverse surface is deformed, the optimal fit parabolic error equation is as follows:

(z _i -φ _F，y x _i +φ _F，x y _i +Δz _F )

Wherein, (x) _i ，y _i ，z _i ) Actually measured three-dimensional space coordinates (delta x) of main and inverse single-point mark points under antenna design coordinate system _F ，Δy _F ，Δz _F ) To optimally match the displacement of the parabolic peak relative to the ideal parabolic peak _F，x 、φ _F，y The rotation quantity of the relative ideal paraboloid around the x and y axes is delta f, and the focal length variation quantity is delta f;

linearizing the error equation and performing iterative solution to obtain the required equivalent pose error, namely (delta x) _F ，Δy _F ，Δz _F )、φ _F，x 、φ _F，y ；

Step 5.2: calculating the position and posture adjustment compensation quantity of the reflecting surface;

the main and inverse pose adjustment compensation quantity is calculated according to the following formula:

the invention provides an integral on-orbit calibration and compensation system for microwave load surface-pose errors, which comprises the following components:

module M1: establishing a satellite coordinate system of each reflecting surface on the ground through a coplanar laser target, and using the satellite coordinate system as a reference coordinate system for adjusting the pose of the reflecting surface;

module M2: calibrating coordinate values of the coding mark points and the common point conversion targets under a main and inverse design coordinate system on the ground, and the relation between the satellite coordinate systems of all the reflecting surfaces and the corresponding laser measurement coordinate systems;

module M3: shooting the main reflecting surface simultaneously by using photogrammetry cameras at different positions during the track period, resolving the three-dimensional coordinates of the single-point mark points on the surface of the main reflecting surface, and converting the three-dimensional coordinates of all the single-point mark points into a main inverse design coordinate system through coding mark points;

Module M4: measuring three-dimensional coordinates of a common point conversion target and a coplanar laser target by using a laser scanning measurement camera during the track period, realizing reference transmission of laser measurement results of the coplanar laser target by using the common point conversion target, unifying the laser measurement results into a main and inverse design coordinate system, and resolving the pose of the reflecting surface under the main and inverse design coordinate system;

module M5: under a main and inverse design coordinate system, performing shape-face matching on the obtained three-dimensional coordinates of the single point mark points on the surface of the main reflecting surface, solving a main and inverse equivalent pose error introduced by the deformation of the main reflecting surface, calculating a reflecting surface pose adjustment compensation quantity by combining the reflecting surface pose and performing reflecting surface pose adjustment, so as to realize integral on-orbit calibration and adjustment compensation of the static track microwave load shape-pose error;

Preferably, the module M1 employs:

wherein a, b and c are undetermined coefficients of plane equations of coplanar laser targets under a laser measurement coordinate system, and the method comprises the following steps ofFitting to obtain;

the module M2 employs:

the origin of the laser measurement coordinate system is recorded as J,the coordinate axis unit direction vector of the coordinate system is measured for the laser,θ, ψ are the satellite coordinate system around the laser measurement coordinate system>Euler with rotary shaftThe rotation matrix R from the laser measurement coordinate system to the reflecting surface satellite coordinate system is obtained by the angle through 3-1-2 conversion:

preferably, the module M3 employs:

module M3.1: simultaneously photographing the main reflecting surface by adopting 4 photogrammetry cameras to obtain 4 main reflecting surface shape images comprising photogrammetry mark points and a surface measurement reference ruler; the photogrammetry mark points comprise coding mark points and single-point mark points;

Module M3.2: automatically identifying, extracting and positioning the coding mark points and the single-point mark points in the 4 pictures to obtain a coding value of each coding mark point, a central image plane coordinate of the coding point and a central image plane coordinate of the single-point mark point;

module M3.3: a stereopair is built based on the main reflection surface-shaped images of adjacent shooting stations, a left image space coordinate system is used as a left image space auxiliary coordinate system, the three axes of a right image space auxiliary coordinate system and the three axes of the left image space auxiliary coordinate system are mutually parallel, and the relative orientation element (b) of the right image relative to the left image is obtained _v ，b _w ，ω ₂ ，k ₂ )；

Wherein: (x) ₀ ，y ₀ F) are intra-azimuth elements of the photo, and the stereopair can be considered to have the same intra-azimuthBit element, rotation matrix R is formed by 3 rotation angles of right photo relative to left photoω ₂ ，κ ₂ ) Composition;

module M3.4: the same-name point matching is carried out on the single-point marking point by utilizing the epipolar line matching principle, and the coordinates of the single-point marking point p1 of the left photo in the space coordinate system of the right photo image are recorded as (x' _p1 ，y′ _p1 ，z′ _p1 ) Left camera station S ₁ The coordinates in the right shot image space coordinate system are (x' _S1 ，y′ _S1 ，z′ _S1 ) From S ₁ 、p ₁ And S is ₂ The three points are coplanar, and the equation of the nuclear plane in the space coordinate system of the right photo image is obtained as follows:

the homonymy epipolar equation is thus:

module M3.5: solving an image space auxiliary coordinate system coordinate initial value of a single point mark point corresponding to the same name image point of the stereopair;

wherein: (X, Y, Z) is the initial value of the coordinates of the auxiliary coordinate system in the single-point mark point image space to be solved, (X) _S ，Y _S ，Z _S ) Spatially-assisted coordinate system coordinates for the camera image (a) ₁ ，a ₂ ，a ₃ ，…，c ₁ ，c ₂ ，c ₃ ) To compose a torque9 parameters of the array; the arrangement is thus possible:

module M3.6: the adjustment of the beam method takes a collineation conditional equation as a basic mathematical model, takes the coordinates of each outside-image azimuth element and the space auxiliary coordinate system of all single-point mark point images as unknowns, and realizes the optimal intersection of the same-name light rays through the rotation and translation of the beam in space;

module M3.7: the least square point fitting is developed for the three-dimensional coordinate measured value of the main and inverse coding mark points and the ground calibration theoretical value, so that the reference transmission from the measurement coordinate system to the main and inverse design coordinate system is realized, and the three-dimensional coordinates of the main and inverse single-point mark points in the main and inverse design coordinate system are determined;

Wherein: lambda is the scale factor of the coefficient of the scale,a rotation matrix from the measurement coordinate system to the main reverse design coordinate system is designed; and then determining a scaling factor according to the measuring length and the calibration length of the surface measuring standard ruler, and uniformly scaling the three-dimensional coordinates of all the single-point mark points to obtain a final measuring result.

Preferably, the module M4 employs:

module M4.1: measuring reference transmission;

step 4.2: respectively establishing a satellite coordinate system of each reflecting surface under a main and inverse design coordinate system to obtain the pose relation of the satellite coordinate system of each reflecting surface relative to the main and inverse design coordinate system, comprising the following steps: a pair of reversed pose: (Q' _F1 ，θ′ _F1 ，ψ′ _F1 ) And (3) carrying out secondary reverse posture: (Q' _F2 ，/>θ′ _F2 ，ψ′ _F2 ) Main and reverse pose: (Q' _F ，/>θ′ _F ，ψ′ _F )；

The module M5 employs:

step 5.1: fitting a shape surface and obtaining an equivalent pose error;

(z _i -φ _F，y x _i +φ _F，x y _i +Δz _F )

compared with the prior art, the invention has the following beneficial effects:

1. the invention provides a method for integrally calibrating and adjusting and compensating an error of a static track microwave load 'shape face-pose', which firstly provides an integral on-orbit calibration algorithm of an electric large-size three-reflection-face fixed-face antenna 'shape face-pose' error of a combined photogrammetry and a laser measurement method, and further solves the problem of adjusting and compensating the pose of a reflection face according to a calibration result, thereby reducing or eliminating the adverse effect of a static track thermal environment on the main beam efficiency and pointing precision of an antenna system and improving the long-time working performance of the static track microwave load under an extreme temperature environment strip line.

2. The invention solves the problems of integral on-orbit calibration and adjustment compensation of static orbit microwave load 'shape face-pose' errors, has the advantages of easy engineering realization and strong operability, can be used for guiding the design of an on-orbit deformation measurement and control subsystem of a static orbit microwave detection satellite, and reduces beam pointing errors and gain loss caused by the thermal deformation of an antenna structure.

Drawings

Other features, objects and advantages of the present invention will become more apparent upon reading of the detailed description of non-limiting embodiments, given with reference to the accompanying drawings in which:

FIG. 1 is a schematic diagram of a photogrammetry system used in the present invention.

FIG. 2 is a schematic diagram of a laser measurement system used in the present invention.

FIG. 3 is a schematic view of a surface measurement reference ruler, a mark point and a target of the photogrammetry system.

Fig. 4 is a schematic diagram of an antenna reflecting surface satellite coordinate system.

FIG. 5 is a flow chart of the overall on-track calibration and adjustment compensation of stationary track microwave load "form-pose" errors in accordance with an embodiment of the present invention.

Fig. 6 is a laser measurement reference transfer flow chart.

Wherein, 1-the main reflecting surface; 2-a first secondary reflective surface; 3-a second secondary reflective surface; 4-a pair of backstay rods; 5-two auxiliary counter stay bars; 6-a first photogrammetry camera; 7-a second photogrammetry camera; 8-a third photogrammetry camera; 9-a fourth photogrammetry camera; 10-a quasi-optical frame; 11-a first laser scanner; 12-a second laser scanner; 13-form surface measuring scale.

Detailed Description

The present invention will be described in detail with reference to specific examples. The following examples will assist those skilled in the art in further understanding the present invention, but are not intended to limit the invention in any way. It should be noted that variations and modifications could be made by those skilled in the art without departing from the inventive concept. These are all within the scope of the present invention.

Example 1

Before describing the specific embodiments, the following description is made of the coordinate system involved:

and (3) a main reverse design coordinate system: origin of coordinate system O _M Is the geometric vertex of a paraboloid of revolution, +z _M The axis coincides with the focal axis of the paraboloid of revolution and points to the geometric vertex of the paraboloid of revolution in the normal direction, +x _M Vertical axis +z _M The axis points to a characteristic direction of the paraboloid of revolution (with the satellite body coordinate system +z _B The axes form an angle of 66.003 °) +y _M Axis and +z _M 、+x _M The axes form a right-hand rectangular coordinate system.

As shown in fig. 4, the satellite coordinate system: the basic plane (XY plane) is the plane where the coplanar laser targets are located, the undetermined coefficient of the plane equation is obtained by least square fitting of point positions under a laser measurement coordinate system, the origin of the coordinate system is the center points of the 4 coplanar laser targets, the +z axis is a plane normal vector, the +x axis is a vector corresponding to the two laser targets in the inclined direction of the reflecting surface, and the +y axis, the +z axis and the +x axis form a right-hand rectangular coordinate system.

In order to overcome the defects in the prior art, the invention provides a method and a system for integrally calibrating and adjusting the shape face-pose errors of a static track microwave load on orbit.

The integral on-orbit calibration and adjustment compensation device based on the static orbit microwave load 'shape face-pose' error comprises:

as shown in fig. 1 to 3, comprising: microwave load, photogrammetry cameras, shape surface measurement reference bars, coding mark points, single-point mark points, laser scanning measurement cameras, common point conversion targets and coplanar laser targets on all reflecting surfaces;

the microwave load comprises an antenna main reflecting surface 1 (primary reverse for short), a first auxiliary reflecting surface 2 (primary reverse for short), a second auxiliary reflecting surface 3 (secondary reverse for short), an antenna stay bar and a quasi-optical system; the three reflection surface lines are arranged on the top plate of the satellite platform through the antenna stay bars; the quasi-optical system is installed through the quasi-optical frame 10 and embedded into the satellite platform; the photogrammetry camera is arranged on a pair of back supporting rods 4, a shape surface measurement reference ruler 13 is fixed on the quasi-optical frame 10, and coding mark points and single-point mark points are stuck on the main back surface; the laser scanning measurement camera is arranged below a pair of reverse stay bars 4 and a quasi-optical frame 10, the common point conversion target is stuck to the center areas of the pair of reverse stay bars 4 and the main reverse surface, and the coplanar laser target is stuck to the three reflecting surfaces. The photogrammetry camera is used for imaging the main reverse surface mark point and the shape surface measurement reference ruler and measuring the accuracy of the main reverse surface; the laser scanning measurement camera is used for measuring three-dimensional coordinates of the common point conversion target and the coplanar laser target, and the reference transmission of the measurement result of the coplanar laser target is realized through the common point conversion target, so that the pose change conditions of the main reverse, the auxiliary reverse and the auxiliary reverse of the antenna are solved under the unified measurement reference.

The stationary track microwave load adopts a three-reflecting-surface fixed-surface antenna to receive microwave signals from the ground surface and the atmosphere, and reflects the microwave signals to a quasi-optical system; the quasi-optical system is used for carrying out polarization separation and frequency separation on the multiple composite microwave signals so as to realize multi-frequency and multi-polarization multiplexing of a single antenna.

The photogrammetry camera has 4 total cameras, including: a first photogrammetry camera 6, a second photogrammetry camera 7, a third photogrammetry camera 8, and a fourth photogrammetry camera 9; the measuring areas are the main counter surface mark point area and the shape surface measuring reference ruler, which are respectively arranged at different positions of a pair of counter stay bars 4.

The shape surface measuring standard ruler 13 is made of low expansion and deformation-free ULE material and is fixed on the quasi-optical frame 10, in the three-dimensional measurement, the scale of the relative orientation model is determined according to the calibration length of the shape surface measuring standard ruler 13 and the length calculated under the relative orientation model, and then the coordinates of all measuring points are uniformly scaled to determine the length standard of a photogrammetric coordinate system.

The coding mark points are distributed on the main surface and the opposite surface, and the correct matching of corresponding image points of all photos can be realized by utilizing the coding information of the coding mark points, so that the registered coding mark point image coordinates are substituted into a relative orientation model as known parameters to calculate relative orientation elements, and automatic relative orientation between stereo pairs is realized.

The single-point marking points are distributed on the main surface and the opposite surface, are used for providing the characteristic points of main and opposite stereo measurement, and the deformation condition of the main and opposite surface is obtained by performing surface anastomosis on the three-dimensional coordinate calculation result of the single-point marking points.

The laser scanning measurement camera is divided into 2 sets, including: a first laser scanner 11 and a second laser scanner 12; the first laser scanners 11 installed on the pair of the back stay bars 4 monitor the change condition of the main reverse pose by measuring the space position of the target point on the main reverse and the second laser scanners 12 installed under the quasi-optical frame 10 monitor the change condition of the main reverse pose by measuring the space position of the target point on the first reverse and the second reverse.

The common point conversion targets are respectively arranged in a pair of back stay bars (6) and a main reverse surface central area (4), and the reference transmission of the laser measurement results of the coplanar laser targets of the reflecting surfaces is realized by utilizing the common point conversion targets; and unifying the measurement data of the two sets of laser scanning measurement cameras to be under a unified reference.

The coplanar laser targets are respectively arranged on three reflecting surfaces (4 reflecting surfaces are arranged on each) and are used for establishing a satellite coordinate system of each reflecting surface, and the pose change condition of each reflecting surface is obtained through direct comparison of an on-orbit calibration result and a ground calibration result of the satellite coordinate system.

Specifically, the microwave load of the static track is mainly reflected to a 5m caliber rotating paraboloid, one pair of the microwave load is reflected to a 1m caliber rotating hyperboloid, and the other pair of microwave load is reflected to a 1.4m caliber plane.

The photogrammetry camera works in a 850nm wave band, the wave band has a slight advantage compared with a 550nm wave band in terms of stray light suppression, the focal length of the system is 16.5mm, the scale of a visible light detector is 5120 pixels multiplied by 5120 pixels, and the size of the pixels is 4.5 mu m.

As shown in fig. 3, the shape surface measuring scale 13 has a length of 1m, and is made of ULE material, and temperature compensation and temperature difference control are performed by sticking a heating sheet.

The coded mark points and the single-point mark points are made of directional reflecting materials, 200 mark points are arranged in 2400mm areas of the main reflecting surface.

Specifically, the wavelength of the laser scanning measurement camera is selected to be 1500/1560nm, and the laser scanning measurement camera can be converted into three-dimensional Cartesian coordinates according to the spherical coordinates of the distance-angle measured under the laser measurement coordinate system.

The invention provides an integral on-orbit calibration and adjustment compensation system for a static orbit microwave load 'shape face-pose' error, which can effectively reduce beam pointing error and gain loss caused by thermal deformation of a reflecting surface structure and ensure the working performance of the static orbit microwave load in the on-orbit service period.

As shown in fig. 4 to 6, according to the method for integrally calibrating and adjusting and compensating the static track microwave load 'shape face-pose' error in an on-orbit manner, the device for integrally calibrating and adjusting and compensating the static track microwave load 'shape face-pose' error in an on-orbit manner comprises the following steps:

step 1: establishing a satellite coordinate system of each reflecting surface on the ground through a coplanar laser target, and using the satellite coordinate system as a reference coordinate system for adjusting the pose of the reflecting surface;

specifically, the step 1 adopts:

the coplanar laser targets are respectively arranged on the main reflecting surface, the first auxiliary reflecting surface and the second auxiliary reflecting surface; 4 coplanar laser targets are arranged on each of the three reflecting surfaces, and are used for establishing a satellite coordinate system of each reflecting surface, and the pose change condition of each reflecting surface is obtained through direct comparison of an on-orbit calibration result and a ground calibration result of the satellite coordinate system;

specifically, as shown in fig. 4, the establishment of the satellite coordinate system employs:

the A, B, C, D laser scanning measuring camera measures three-dimensional coordinates of 4 targets, namely A (x, y, z), B (x, y, z), C (x, y, z) and D (x, y, z), respectively. Taking 4 coplanar target centers Q as the origin of a reflecting surface satellite coordinate system, and the following formula is as follows:

Step 2: coordinate values of the coded mark points and the common point conversion targets under the main and inverse design coordinate systems are calibrated on the ground, and the relation between the satellite coordinate systems of all reflecting surfaces and the corresponding laser measurement coordinate systems is unified for measurement references in the step 3 and the step 4.

The origin of the laser measurement coordinate system is recorded as J,the coordinate axis unit direction vector of the coordinate system is measured for the laser,θ, ψ are the satellite coordinate system around the laser measurement coordinate system>The Euler angle of shaft rotation can obtain a rotation matrix R from a laser measurement coordinate system to a reflecting surface satellite coordinate system by 3-1-2 rotation order, wherein the rotation matrix R is as follows:

the pose of the satellite coordinate system relative to the laser measurement coordinate system can be obtained by the method:

step 3: and shooting the main and the counter simultaneously by using photogrammetry cameras at different positions during the track period, calculating the three-dimensional coordinates of the single-point mark points on the main and the counter according to the multi-dimensional measurement source, and converting the three-dimensional coordinates of all the single-point mark points into a main and the counter design system through the coding mark points.

Step 3.1: and 4 photogrammetry cameras are adopted to photograph the main lens and the main lens at the same time, so that 4 main lens images containing photogrammetry mark points and a shape surface measurement reference ruler are obtained, wherein the photogrammetry mark points comprise coding mark points and single-point mark points.

Step 3.2: and (3) automatically identifying, extracting and positioning the coding marking points and the single-point marking points in the 4 images with high precision to obtain the coding value of each coding marking point, the central image plane coordinates of the coding points and the central image plane coordinates of the single-point marking points.

Step 3.3: the stereopair is relatively oriented; a stereoscopic image pair is built based on adjacent photographing station main inverse-shape images, a left image space coordinate system is used as an image space auxiliary coordinate system of the image pair, three axes of a right image space auxiliary coordinate system and three axes of the left image space auxiliary coordinate system are parallel to each other, and a relative orientation coplanarity condition equation is utilized to calculate a relative orientation element (b) of the right image relative to the left image _v ，b _w ，ω ₂ ，κ ₂ )：

Wherein: (x) ₀ ，y ₀ F) is the internal azimuth element of the photo, the stereopair can be considered to have the same internal azimuth element, and the rotation matrix R is formed by the rotation angle of 3 degrees of the right photo relative to the left photoω ₂ ，κ ₂ ) Composition is prepared.

Step 3.4: matching the epipolar lines of the same-name image points; the core line matching principle is utilized to match the same name point of the single point mark points, and the single point mark point p of the left photo is recorded ₁ The coordinates in the right shot image space coordinate system are (x' _p1 ，y′ _p1 ，z′ _p1 ) Left camera station S ₁ The coordinates in the right shot image space coordinate system are (x' _S1 ，y′ _S1 ，z′ _S1 ) From S ₁ 、p ₁ And S is ₂ The three points are coplanar (nuclear surface), and the equation of the nuclear surface in the space coordinate system of the right photo image can be obtained as follows:

the homonymy epipolar equation is thus:

and respectively calculating the distance from each pixel of the right photo to the homonymous epipolar line, taking the minimum value to judge whether the distance is smaller than 1, and judging the distance to be the homonymous image point of the single-point mark point of the left photo if the distance is smaller than 1.

Step 3.5: stereopair front intersection: solving an initial value of coordinates of an image space auxiliary coordinate system of a single point marking point corresponding to the same name image point of the stereopair based on a collineation conditional equation:

wherein: (X, Y, Z) is the initial value of the coordinates of the auxiliary coordinate system in the single-point mark point image space to be solved, (X) _S ，Y _S ，Z _S ) Spatially-assisted coordinate system coordinates for the camera image (a) ₁ ，a ₂ ，a ₃ ，…，c ₁ ，c ₂ ，c ₃ ) For 9 parameters that make up the rotation matrix. The arrangement is thus possible:

if the n images contain the same single point marker, 2n linear equations can be listed to solve the initial coordinate values (X, Y, Z) of the auxiliary coordinate system of the single point marker image space.

Step 3.6: stereo pair beam method adjustment; the beam method adjustment takes a collineation conditional equation as a basic mathematical model, takes the coordinates of each outside-image azimuth element and the auxiliary coordinate system of the image space of all single-point mark points as unknowns, and realizes the optimal intersection of the same-name light rays through the rotation and translation of the light beams in space:

The initial values of the outside-photo azimuth elements and the single-point mark point image space auxiliary coordinate system coordinates are respectively determined by the step 3.4 and the step 3.5.

Step 3.7: measuring reference transmission; and (3) expanding least square point fitting for the three-dimensional coordinate measured value of the main and inverse coding mark points and the ground calibration theoretical value, realizing reference transmission from a measurement coordinate system to a main and inverse design coordinate system, and determining the three-dimensional coordinates of the main and inverse single-point mark points in the main and inverse design coordinate system:

wherein: lambda is the scale factor of the coefficient of the scale,a rotation matrix of the coordinate system is designed for measuring the coordinate system to the main inverse. And then determining a scaling factor according to the measuring length and the calibration length of the surface measuring standard ruler, and uniformly scaling the three-dimensional coordinates of all the single-point mark points to obtain a final measuring result.

Step 4: and measuring three-dimensional coordinates of the common point conversion target and the coplanar laser target by using a laser scanning measurement camera during the track period, realizing reference transmission of laser measurement results of the coplanar laser target by using the common point conversion target, unifying the laser measurement results into a main and inverse design system, and resolving the pose of the reflecting surface under the main and inverse design coordinate system.

Specifically, the step 4 adopts:

step 4.1: measuring reference transmission; as shown in fig. 5;

Note p= (P ₁ ，p ₂ ，…，p _n ) Sum q= (Q ₁ ，q ₂ ，…，q _n ) For the common point conversion target coordinate measurement value on a pair of back struts obtained by the first and second laser scanning measurement cameras, a singular value decomposition method is adopted to solve a rotation matrix between the first and second laser measurement coordinate systems and a common measurement coordinate systemLaser measurement coordinate system two and laser measurement seatThe standard is a measurement standard transmission process as follows:

step 4.2: respectively establishing a satellite coordinate system of each reflecting surface after the on-orbit change under a main reverse design coordinate system, and obtaining the pose relation of the satellite coordinate system of each reflecting surface relative to the main reverse design coordinate system through the calculation process in the step 2;

the origin of the primary inverse design system is denoted as M,the coordinate axis unit direction vector of the system is designed for the main reverse direction, < + >>Theta and psi are respectively the main reverse design system of the satellite coordinate system>The Euler angle of shaft rotation can obtain a rotation matrix B from a main inverse design system to a reflecting surface satellite coordinate system by 3-1-2 rotation order, wherein the rotation matrix B is as follows:

the pose of the satellite coordinate system relative to the main reverse design system can be obtained by the method:

Namely a pair of reverse postures: (Q' _F1 ，θ′ _F1 ，ψ′ _F1 ) And (3) carrying out secondary reverse posture: (Q' _F2 ，/>θ′ _F2 ，ψ′ _F2 ) Main and reverse pose: (Q' _F ，/>θ′ _F ，ψ′ _F )。

Step 5: and performing shape-face matching according to the three-dimensional coordinates of the main and inverse single-point mark points, solving an equivalent pose error introduced by deformation of the main and inverse shape faces, calculating a reflecting face pose adjustment compensation quantity according to a reflecting face pose calculation result, and performing reflecting face pose adjustment to realize integral on-orbit calibration and adjustment compensation of the stationary orbit microwave load shape-pose error.

Specifically, the step 5 employs:

step 5.1: fitting a shape surface and obtaining an equivalent pose error;

(z _i -φ _F，y x _i +φ _F，x y _i +Δz _F )

wherein, (x) _i ，y _i ，z _i ) Actually measured three-dimensional space coordinates (delta x) of main and inverse single-point mark points under antenna design coordinate system _F ，Δy _F ，Δz _F ) To be optimalThe displacement of the vertex of the coincident paraboloid relative to the vertex of the ideal paraboloid phi _F，x 、φ _F，y Δf is the amount of focal length change, which is the amount of rotation of the relatively ideal paraboloid about the x, y axes.

Linearizing the error equation and performing iterative solution to obtain the required equivalent pose error, namely (delta x) _F ，Δy _F ，Δz _F )、φ _F，x 、φ _F，y 。

1. the pose measurement adjustment process of the secondary aspect is similar to that of the primary aspect, and will not be repeated here. And (3) continuously repeating the steps 3 to 5 during the on-orbit service period of the stationary orbit microwave load, so that the integral on-orbit calibration and adjustment compensation of the 'shape face-pose' error of the reflecting face can be realized, and the working performance of the load is ensured.

The invention also provides a static track microwave load 'shape face-pose' error integral on-orbit calibration and adjustment compensation system, which can be realized by executing the flow steps of the static track microwave load 'shape face-pose' error integral on-orbit calibration and adjustment compensation method, namely, a person skilled in the art can understand the static track microwave load 'shape face-pose' error integral on-orbit calibration and adjustment compensation method as a preferred implementation mode of the static track microwave load 'shape face-pose' error integral on-orbit calibration and adjustment compensation system.

Those skilled in the art will appreciate that the invention provides a system and its individual devices, modules, units, etc. that can be implemented entirely by logic programming of method steps, in addition to being implemented as pure computer readable program code, in the form of logic gates, switches, application specific integrated circuits, programmable logic controllers, embedded microcontrollers, etc. Therefore, the system and various devices, modules and units thereof provided by the invention can be regarded as a hardware component, and the devices, modules and units for realizing various functions included in the system can also be regarded as structures in the hardware component; means, modules, and units for implementing the various functions may also be considered as either software modules for implementing the methods or structures within hardware components.

In the description of the present application, it should be understood that the terms "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," and the like indicate orientations or positional relationships based on the orientations or positional relationships illustrated in the drawings, merely to facilitate description of the present application and simplify the description, and do not indicate or imply that the devices or elements being referred to must have a specific orientation, be configured and operated in a specific orientation, and are not to be construed as limiting the present application.

The foregoing describes specific embodiments of the present invention. It is to be understood that the invention is not limited to the particular embodiments described above, and that various changes or modifications may be made by those skilled in the art within the scope of the appended claims without affecting the spirit of the invention. The embodiments of the present application and features in the embodiments may be combined with each other arbitrarily without conflict.

Claims

1. The method for integrally calibrating and compensating the microwave load surface-pose error on-orbit is characterized by comprising the following steps of:

2. The method for integral on-orbit calibration and compensation of microwave load profile-pose errors according to claim 1, wherein said step S1 employs:

wherein a, b and c are undetermined coefficients of plane equations of coplanar laser targets under a laser measurement coordinate system, and the method comprises the following steps of Fitting to obtain the final product.

3. The method for integral on-orbit calibration and compensation of microwave load profile-pose errors according to claim 1, wherein said step S2 employs:

the origin of the laser measurement coordinate system is recorded as J,measuring coordinate axis unit direction vector of coordinate system for laser, < >>Omega and psi are the satellite coordinate system around the laser measuring coordinate system +.>The Euler angle of shaft rotation, the rotation matrix R from the laser measurement coordinate system to the reflecting surface satellite coordinate system is obtained by 3-1-2 rotation sequence:

4. the method for integral on-orbit calibration and compensation of microwave load profile-pose errors according to claim 1, wherein said step S3 employs:

Step S3.3: establishing a stereopair based on the main reflection surface images of adjacent shooting stations, taking a left image space coordinate system as a left image space auxiliary coordinate system, and obtaining the relative orientation element of the right image relative to the left image by mutually parallel three axes of the right image space auxiliary coordinate system and the left image space auxiliary coordinate system

Wherein: (x) ₀ ，y ₀ F) is the intra-azimuth element of the shot, and the stereopair can be considered to have the same intra-azimuth element, the rotation matrix R being defined by 3 rotation angles of the right shot relative to the left shotComposition;

the homonymy epipolar equation is thus:

5. The method for integral on-orbit calibration and compensation of microwave load profile-pose errors according to claim 1, wherein said step S4 employs:

step S4.1: measuring reference transmission;

step 4.2: respectively establishing a satellite coordinate system of each reflecting surface under a main and inverse design coordinate system to obtain the pose relation of the satellite coordinate system of each reflecting surface relative to the main and inverse design coordinate system, comprising the following steps: a pair of reversed pose:and (3) carrying out secondary reverse pose:main and reverse pose: />

6. The method for integral on-orbit calibration and compensation of microwave load profile-pose errors according to claim 1, wherein said step S5 employs:

Step 5.1: fitting a shape surface and obtaining an equivalent pose error;

linearizing the error equation and performing iterative solution to obtain the required equivalent pose error, namely (delta x) _F ，Δy _F ,Δz _F )、φ _F,x 、φ _F，y

7. the utility model provides a microwave load shape face-position appearance error is whole to be in orbit demarcation and compensation system which characterized in that includes:

8. The microwave load profile-pose error integrated in-orbit calibration and compensation system according to claim 7, wherein said module M1 employs:

the module M2 employs:

the origin of the laser measurement coordinate system is recorded as J,measuring coordinate axis unit direction vector of coordinate system for laser, < >>θ, ψ are the satellite coordinate system around the laser measurement coordinate system>The Euler angle of shaft rotation, the rotation matrix R from the laser measurement coordinate system to the reflecting surface satellite coordinate system is obtained by 3-1-2 rotation sequence:

9. The microwave load profile-pose error integrated in-orbit calibration and compensation system according to claim 7, wherein said module M3 employs:

module M3.3: establishing a stereopair based on the main reflection surface images of adjacent shooting stations, taking a left image space coordinate system as a left image space auxiliary coordinate system, and obtaining the relative orientation element of the right image relative to the left image by mutually parallel three axes of the right image space auxiliary coordinate system and the left image space auxiliary coordinate system

Wherein: (x) ₀ ，y ₀ F) is the intra-azimuth element of the photo, and the stereopair can be considered to have the same intra-azimuth element, the rotation matrix R is composed of3 rotation angles of right photo relative to left photo Composition;

module M3.4: the core line matching principle is utilized to match the same name point of the single point mark points, and the single point mark point p of the left photo is recorded ₁ The coordinates in the right shot image space coordinate system are (x' _p1 ，y′ _p1 ，z′ _p1 ) Left camera station S ₁ The coordinates in the right shot image space coordinate system are (x' _S1 ，y′ _S1 ，z′ _S1 ) From S ₁ 、p ₁ And S is ₂ The three points are coplanar, and the equation of the nuclear plane in the space coordinate system of the right photo image is obtained as follows:

the homonymy epipolar equation is thus:

wherein: (X, Y, Z) is the initial value of the coordinates of the auxiliary coordinate system in the single-point mark point image space to be solved, (X) _S ，Y _S ，Z _S ) Spatially-assisted coordinate system coordinates for the camera image (a) ₁ ，a ₂ ，a ₃ ，…，c ₁ ，c ₂ ，c ₃ ) To form a spiral9 parameters of the transfer matrix; the arrangement is thus possible:

10. The microwave load profile-pose error integrated in-orbit calibration and compensation system according to claim 7, wherein said module M4 employs:

module M4.1: measuring reference transmission;

solving rotation matrix between laser measurement coordinate system one and main inverse design coordinate system through main inverse surface central region common point conversion target point position least square fitting The laser measurement coordinate system one and the main reverse design coordinate system measurement reference transmission process is as follows:

The module M5 employs:

step 5.1: fitting a shape surface and obtaining an equivalent pose error;

linearizing the error equation and performing iterative solution to obtain the required equivalent pose error, namely (delta x) _F ，Δy _F ,Δz _F )、φ _F，x 、φ _F,y