CN114859326A - Geometric correction method and device for placement error of unmanned airborne radar - Google Patents

Geometric correction method and device for placement error of unmanned airborne radar Download PDF

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CN114859326A
CN114859326A CN202210314982.6A CN202210314982A CN114859326A CN 114859326 A CN114859326 A CN 114859326A CN 202210314982 A CN202210314982 A CN 202210314982A CN 114859326 A CN114859326 A CN 114859326A
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error
angle
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腾格尔
吴昊昊
李子扬
周春城
程赛
马灵玲
王宁
李传荣
唐伶俐
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    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01S—RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
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    • G01S—RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
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Abstract

The invention provides a geometric correction method for a placement error of an unmanned airborne radar, which comprises the following steps: laying a plurality of reflecting marks in a calibration field, and laying a reference point and a check point outside the calibration field; acquiring coordinates of each reflecting target based on the reference point and the check point; controlling an unmanned aerial vehicle carrying a laser radar to fly back and forth along a preset route and pass through the plurality of reflectors, and acquiring attitude information and position information of the unmanned aerial vehicle; acquiring the slant distance and the beam splitting angle from the laser radar transmitting point to the ground reflecting point; based on the position deviation and rotation geometric relation of the laser radar and the integrated navigation system, constructing an error equation according to the coordinates of the reflecting target, the slant range, the beam splitting angle, the attitude information and the position information; solving the error equation to obtain a system error of the unmanned airborne radar installation angle; and geometrically correcting the placement angle by using the system error of the placement angle.

Description

Geometric correction method and device for placement error of unmanned airborne radar
Technical Field
The invention relates to the technical field of laser radars, in particular to a geometric correction method and device for an unmanned aerial vehicle radar installation error.
Background
An Unmanned airborne laser radar (Unmanned airborne laser Detection and Ranging) is an active remote sensing technology for rapidly acquiring three-dimensional spatial information of a terrain surface, and integrates a high-precision laser scanner, a position and attitude measurement system, a power supply and distribution module and a comprehensive control and storage module into a whole. Different from the traditional optical imaging mechanism, the laser radar can acquire the data of the target ground object without the image under the illumination condition.
The unmanned airborne laser radar is formed by assembling a plurality of loads such as a position and attitude measuring system, a laser scanner and the like, when the system is integrated, strict registration among a plurality of sensors is theoretically ensured, but due to the limitation of technical conditions, certain arrangement errors exist among all component systems, and the system arrangement angle errors are mainly errors caused by the fact that a laser scanning coordinate system and an inertial platform coordinate system are not parallel, and comprise pitch angle errors, roll angle errors and yaw angle errors. The existence of the placement error not only influences the absolute precision of the point cloud coordinates, but also causes the three-dimensional space offset between the homonymous features of the overlapped navigation bands, and influences the processing and application of subsequent point cloud data. Therefore, the method can remove the system installation angle error through the rigorous geometric imaging model of the unmanned airborne laser radar, and is particularly important for accurately extracting subsequent point cloud information.
In the process of realizing the conception of the invention, the inventor finds that the calibration accuracy of the unmanned airborne laser radar system is not high by adopting methods such as manual calibration, adjustment of flight band or establishment of a system error model in the prior art and the like, and needs to be improved.
Disclosure of Invention
In view of the above, the present invention provides a geometric correction method for a positioning error of an unmanned aerial vehicle radar, including: laying a plurality of reflecting marks in a calibration field, and laying a reference point and a check point outside the calibration field; acquiring coordinates of each reflecting target based on the reference point and the check point; controlling an unmanned aerial vehicle carrying a laser radar to fly back and forth along a preset route and pass through the plurality of reflectors, and acquiring attitude information and position information of the unmanned aerial vehicle; acquiring the slant distance and the beam splitting angle from the laser radar transmitting point to the ground reflecting point; based on the position deviation and rotation geometric relation of the laser radar and the integrated navigation system, constructing an error equation according to the coordinates of the reflecting target, the slant range, the beam splitting angle, the attitude information and the position information; solving the error equation to obtain a system error of the unmanned airborne radar installation angle; and geometrically correcting the installation angle by using the system error of the installation angle.
According to an embodiment of the present invention, wherein the acquiring coordinates of each reflector based on the reference point and the check point includes: and taking the reference point as a measuring station, taking the check point as an orientation point, and respectively acquiring the coordinates of each reflecting mark by adopting a total station.
According to the embodiment of the present invention, the acquiring the attitude information and the position information of the drone includes: erecting a GPS base station on the reference point; and taking the reference point as a base station, and performing integrated navigation calculation by adopting a difference after GPS to obtain the attitude information and the position information.
According to an embodiment of the present invention, the constructing a geometric verification model according to the slant range, the beam splitting angle, the attitude information, and the position information based on the position offset and the rotation geometric relationship between the lidar and the integrated navigation system includes: and constructing the error equation by using the principle that the distance residual error of the slant distance is minimum.
According to the embodiment of the present invention, wherein the error equation is:
Figure BDA0003568173430000021
wherein:
Figure BDA0003568173430000022
Figure BDA0003568173430000023
Figure BDA0003568173430000024
wherein the content of the first and second substances,
Figure BDA0003568173430000031
is the distance residual of the slope distance rho, rho x 、ρ y 、ρ z The components of the skew distances in the x, y and z directions in a WGS-84 space rectangular coordinate system, rho x0 、ρ y0 、ρ z0 Are respectively rho x 、ρ y 、ρ z The initial value of (a) is,
Figure BDA0003568173430000032
the coordinates of the ith reflecting mark in the WGS-84 space rectangular coordinate system,
Figure BDA0003568173430000033
for the coordinates of the phase center of the antenna corresponding to the ith reflector in the WGS-84 rectangular space coordinate system, [ Delta X [ ] Ai_IMU ΔY Ai_IMU ΔZ Ai_IMU ] T For the laser emission reference center and the inertial unit reference center corresponding to the ith reflecting markLinear offset, R wgs84 A transformation matrix from a North and West high coordinate system to a WGS-84 space rectangular coordinate system; r ENU A transformation matrix from a north east high coordinate system to a north west high coordinate system; r H An instantaneous azimuth attitude angle rotation matrix of the inertial measurement unit; r P An instantaneous pitching attitude angle rotation matrix of the inertial measurement unit is obtained; r R For instantaneous roll attitude angle rotation matrix, R, of the inertial measurement unit M Is a rotation matrix of the arrangement angle of the reference center of the laser emission and the reference center of the inertia unit,
Figure BDA0003568173430000034
Kappa is an azimuth attitude angle, a pitch attitude angle and a roll attitude angle respectively, alpha is an included angle between the projection of the laser emission light path on the XOY surface of the body coordinate system and the positive direction of the X axis, beta is an included angle between the laser emission light path and the projection line of the laser emission light path on the XOY surface, and d omega, c,
Figure BDA0003568173430000035
d kappa is omega,
Figure BDA0003568173430000036
And d ρ is a correction value of the distance residual corresponding to ρ.
According to the embodiment of the invention, solving the error equation to obtain the system error of the positioning angle of the unmanned aerial vehicle radar comprises: solving for less than a preset threshold value
Figure BDA0003568173430000037
Corresponding d ω,
Figure BDA00035681734300000310
d κ, d ρ are the systematic errors of the setting angles.
According to the embodiment of the invention, the error equation is solved by adopting an iterative solution mode.
According to an embodiment of the present invention, wherein the geometrically correcting the placement angle by using the systematic error of the placement angle comprises: the d omega obtained by current solution,
Figure BDA0003568173430000038
d kappa and d rho are respectively accumulated to omega, d rho obtained by the previous solution,
Figure BDA0003568173430000039
And k and p are used as the positioning angles after geometric correction.
In another aspect, the present invention provides a geometric correction apparatus for an installation error of an unmanned aerial vehicle radar, including: the layout module is used for laying a plurality of reflecting targets in a calibration field and laying a reference point and a check point outside the calibration field; a first acquisition module for acquiring coordinates of each of the reflectors based on the reference points and the check points; the second acquisition module is used for controlling the unmanned aerial vehicle carrying the laser radar to fly back and forth along a preset air route and pass through the plurality of reflectors, and acquiring attitude information and position information of the unmanned aerial vehicle; the third acquisition module is used for acquiring the slant distance and the beam splitting angle from the laser radar transmitting point to the ground reflecting point; the building module is used for building an error equation according to the coordinate of the reflecting target, the slant distance, the beam splitting angle, the attitude information and the position information based on the position deviation and rotation geometric relation between the laser radar and the integrated navigation system; the calculation module is used for solving the error equation to obtain the system error of the unmanned aerial vehicle radar installation angle; and the correction module is used for carrying out geometric correction on the installation angle by utilizing the system error of the installation angle.
According to the geometric correction method for the placement error of the unmanned airborne radar, provided by the invention, a plurality of ground control points are distributed, a ground reflector is used as a geometric control point, an error equation corresponding to the placement angle error of the unmanned airborne radar is constructed based on the principle that the distance residual error between a laser radar transmitting point and the ground geometric control point is minimum, and the system error parameter of the placement angle is solved by a least square iterative calculation method, so that the optimal solution of the placement error of the airborne laser radar can be realized, the three-dimensional precision of the laser radar point cloud is further improved, and the application accuracy of the point cloud data in other aspects is finally improved.
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The above and other objects, features and advantages of the present invention will become more apparent from the following description of the embodiments of the present invention with reference to the accompanying drawings, in which:
fig. 1 schematically shows a flow chart of a method for geometry correction of an unmanned airborne radar placement error according to an embodiment of the invention.
FIG. 2 schematically illustrates a design layout of a reflectron according to an embodiment of the present invention.
FIG. 3 schematically illustrates a design layout of fiducial points and checkpoints according to an embodiment of the invention.
Detailed Description
In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention is described in further detail below with reference to specific embodiments and the accompanying drawings. It is to be understood that the embodiments described are only a few embodiments of the present invention, and not all embodiments. All other embodiments, which can be obtained by a person skilled in the art without making any creative effort based on the embodiments in the present invention, belong to the protection scope of the present invention.
The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. The terms "comprises," "comprising," and the like, as used herein, specify the presence of stated features, steps, operations, and/or components, but do not preclude the presence or addition of one or more other features, steps, operations, or components.
In the present invention, unless otherwise expressly specified or limited, the terms "mounted," "connected," "secured," and the like are to be construed broadly and can, for example, be fixedly connected, detachably connected, or integrally formed; can be mechanically connected, electrically connected or can communicate with each other; either directly or indirectly through intervening media, either internally or in any other suitable relationship. The specific meanings of the above terms in the present invention can be understood by those skilled in the art according to specific situations.
In the description of the present invention, it is to be understood that the terms "longitudinal," "length," "circumferential," "front," "rear," "left," "right," "top," "bottom," "inner," "outer," and the like are used in the orientation or positional relationship indicated in the drawings for convenience in describing the present invention and for simplicity in description, and are not intended to indicate or imply that the referenced subsystems or elements must have a particular orientation, be constructed and operated in a particular orientation, and thus, are not to be construed as limiting the present invention.
Throughout the drawings, like elements are represented by like or similar reference numerals. And conventional structures or constructions will be omitted when they may obscure the understanding of the present invention. And the shapes, sizes and positional relationships of the components in the drawings do not reflect the actual sizes, proportions and actual positional relationships. In addition, in the present invention, any reference signs placed between parentheses shall not be construed as limiting the claim.
Similarly, in the above description of exemplary embodiments of the invention, various features of the invention are sometimes grouped together in a single embodiment, figure, or description thereof for the purpose of streamlining the disclosure and aiding in the understanding of one or more of the various disclosed aspects. Reference to the description of the terms "one embodiment," "some embodiments," "an example," "a specific example," or "some examples," etc., means that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the invention. In this specification, the schematic representations of the terms used above do not necessarily refer to the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.
Furthermore, the terms "first", "second" and "first" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of the present invention, "a plurality" means at least two, e.g., two, three, etc., unless specifically limited otherwise.
Aiming at the problems existing in the conventional calibration of the setting angle of the unmanned airborne laser radar, on the basis of deeply exploring the data acquisition mechanism of the airborne laser radar and the influence effect of the setting angle error among multiple sensors on the point cloud data of the laser radar, the method for assisting in eliminating the setting error of the unmanned airborne laser radar by laying multiple reflecting marks on the ground is provided, a ground target is used as a geometric control point, the setting angle error of a scanner and a combined navigation system on an unmanned airborne platform is corrected through least square iterative calculation, and finally the setting angle error is brought into a resolving model of the unmanned airborne laser radar, so that the geometric calibration of the setting error parameter of the unmanned airborne laser radar is realized.
Fig. 1 schematically shows a flow chart of a method for geometry correction of an unmanned airborne radar placement error according to an embodiment of the invention.
As shown in fig. 1, the method for extracting a target of a remote sensing image may include operations S101 to S106, for example.
In operation S101, a plurality of reflectors are arranged within a calibration field, and reference points and inspection points are arranged outside the calibration field.
In the embodiment of the invention, an area is defined on a flat ground to form a calibration field, a plurality of control points are arranged on the calibration field at equal intervals, a reflecting mark is arranged on each control point, and 1 datum point and 1 check point are arranged outside the control points.
FIG. 2 schematically illustrates a design layout of a reflectron according to an embodiment of the present invention.
FIG. 3 schematically illustrates a design layout of fiducial points and checkpoints according to an embodiment of the invention.
As shown in fig. 2, for example, 16 control points a1 and a2 … … a16 are arranged on a flat ground at equal intervals, a strong reflection target with the size of 1cm × 1cm is arranged on each control point, and a reference point B1 and a check point B2 are arranged outside the 16 control points. It should be understood that the number of control points can be selected according to actual requirements, and the invention is not limited thereto.
In operation S102, coordinates of each of the targets are acquired based on the reference points and the check points.
In the embodiment of the invention, firstly, the coordinate of the reference point B1 and the check point B2 point under the space rectangular coordinate of WGS84 is obtained by a method of joint measurement with a known control point
Figure BDA0003568173430000061
And
Figure BDA0003568173430000062
then, the reference point B1 is used as a measuring station, the check point B2 is used as an orientation point, and the total station is used to respectively acquire the coordinates of the reflectors of the control points, for example, coordinates of the reflectors of a1, a2 … … a16 and 16 control points are acquired
Figure BDA0003568173430000071
In operation S103, the unmanned aerial vehicle carrying the laser radar is controlled to fly back and forth along the preset route through the plurality of reflectors, and attitude information and position information of the unmanned aerial vehicle are acquired.
In the embodiment of the present invention, first, a GPS base station may be installed at the reference point B1 for static observation.
And then, mounting the laser radar equipment on the unmanned aerial vehicle, controlling the unmanned aerial vehicle to fly back and forth along a fixed route and pass through all control points, taking the point B1 as a base station, and performing combined navigation calculation by adopting a GPS (global positioning system) post-differential technology to acquire attitude information and position information of the unmanned aerial vehicle.
In operation S104, a slant distance and a beam splitting angle from the laser radar transmission point to the ground reflection point are acquired.
In the embodiment of the invention, the slant distance refers to the slant distance from a laser radar system transmitting point to a ground reflecting point (laser foot point), and the beam splitting angle comprises included angles alpha and beta between laser and a XOY plane of a scanner.
In operation S105, an error equation is constructed according to the coordinates, the slant range, the beam splitting angle, the attitude information, and the position information of the reflection target based on the position offset and the rotation geometry relationship of the laser radar and the integrated navigation system.
Firstly, point cloud coordinates of a reflecting mark in a forward route and a backward route are established, and the method comprises the following specific steps:
Figure BDA0003568173430000072
wherein the content of the first and second substances,
Figure BDA0003568173430000073
the coordinates of the target in a WGS-84 space rectangular coordinate system are used;
Figure BDA0003568173430000074
is the coordinate of the phase center of the antenna in a WGS-84 space rectangular coordinate system, R wgs84 A transformation matrix from a North and West high coordinate system to a WGS-84 space rectangular coordinate system; r ENU A transformation matrix from a north east high coordinate system to a north west high coordinate system; r H An instantaneous azimuth attitude angle rotation matrix of the inertial measurement unit; r P An instantaneous pitching attitude angle rotation matrix of the inertial measurement unit is obtained; RR is instantaneous roll attitude angle rotation matrix of inertial measurement unit, R M The method is characterized in that the method is a setting angle rotation matrix of a laser emission reference center and an inertia unit reference center, alpha is an included angle between the projection of a laser emission light path on an XOY surface of a body coordinate system and the positive direction of an X axis, beta is an included angle between the laser emission light path and a projection line of the laser emission light path on the XOY surface, and rho is an oblique distance.
Wherein:
Figure BDA0003568173430000081
Figure BDA0003568173430000082
Figure BDA0003568173430000083
Figure BDA0003568173430000084
then, based on the above relationship, an error equation is constructed by using the principle that the distance residual from the laser emission center to the three-dimensional direction (slope distance) of the ground reflecting mark is minimum.
Specifically, the following equation is given by taking the minimum three-dimensional residual error from the laser emission center to the real coordinate of the ground reflecting standard as a principle:
Figure BDA0003568173430000085
Figure BDA0003568173430000086
Figure BDA0003568173430000087
substituting the initial value alpha of the included angle 0 、β 0 And ground truth point coordinate X A_GCP 、Y A_GCP And Z A_GCP Generating an initial distance value ρ x0 、ρ y0 、ρ z0 And obtaining the following data by performing linear processing on an error equation in a principle that the three-dimensional residual error from the laser emission center to the real coordinate of the ground reflecting standard is minimum:
Figure BDA0003568173430000088
Figure BDA0003568173430000089
Figure BDA00035681734300000810
then, the distance between the laser emission center and the ground foot point is calculated simultaneously during the adjustment, and the correction quantity of the slope distance rho is introduced
Figure BDA0003568173430000091
Figure BDA0003568173430000092
Figure BDA0003568173430000093
And then, carrying out least square adjustment calculation by adopting an indirect adjustment formula, wherein an error equation can be listed according to a conditional formula V which is AX-L:
Figure BDA0003568173430000094
wherein the content of the first and second substances,
Figure BDA0003568173430000095
is the distance residual of the slope distance rho, rho x 、ρ y 、ρ z The components of the skew distances in the x, y and z directions in a WGS-84 space rectangular coordinate system, rho x0 、ρ y0 、ρ z0 Are respectively rho x 、ρ y 、ρ z The initial value of (a) is,
Figure BDA0003568173430000096
the coordinates of the ith reflecting mark in the WGS-84 space rectangular coordinate system,
Figure BDA0003568173430000097
for the coordinates of the phase center of the antenna corresponding to the ith reflector in the WGS-84 rectangular space coordinate system, [ Delta X [ ] Ai_IMU ΔY Ai_IMU ΔZ Ai_IMU ] T Linear offset R of the laser emission reference center corresponding to the ith reflector and the reference center of the inertial unit wgs84 A transformation matrix from a North and West high coordinate system to a WGS-84 space rectangular coordinate system; r ENU Is a high coordinate system of northeastA transformation matrix of a northwest high coordinate system; r H An instantaneous azimuth attitude angle rotation matrix of the inertial measurement unit; r P An instantaneous pitching attitude angle rotation matrix of the inertial measurement unit is obtained; r R For instantaneous roll attitude angle rotation matrix, R, of the inertial measurement unit M A rotation matrix of the arrangement angles of the reference center of the laser emission and the reference center of the inertial unit,
Figure BDA0003568173430000098
Kappa is an azimuth attitude angle, a pitch attitude angle and a roll attitude angle respectively, alpha is an included angle between the projection of the laser emission light path on the XOY surface of the body coordinate system and the positive direction of the X axis, beta is an included angle between the laser emission light path and the projection line of the laser emission light path on the XOY surface, and d omega, c,
Figure BDA0003568173430000099
d kappa is omega,
Figure BDA00035681734300000910
Kappa, dp is a correction value of the distance residual corresponding to ρ,
Figure BDA0003568173430000101
are respectively rho x 、ρ y 、ρ z To omega,
Figure BDA0003568173430000102
The partial coefficient of κ.
Converting the error equation into a normal equation according to a least square indirect adjustment principle:
(A T PA)X＝A T PL
wherein, P is a unit weight array of the observed value;
Figure BDA0003568173430000103
Figure BDA0003568173430000104
Figure BDA0003568173430000105
an expression listing the solution of the normal equation:
Figure BDA0003568173430000106
in operation S106, an error equation is solved to obtain a system error of the placement angle of the unmanned aerial vehicle radar, and the placement angle is geometrically corrected by using the system error of the placement angle.
In the embodiment of the invention, the error equation can be solved by adopting an iterative solution mode to obtain the error equation smaller than the preset threshold value
Figure BDA0003568173430000107
Corresponding d ω,
Figure BDA0003568173430000108
d κ and d ρ are the systematic errors of the placement angles.
Specifically, first, d ω,
Figure BDA0003568173430000109
And substituting the initial values of d kappa and d rho into an expression of a normal equation solution to solve the X matrix.
Then, substituting the X matrix into an error equation to obtain a residual vector matrix
Figure BDA00035681734300001010
Next, the residual vector matrix is determined
Figure BDA0003568173430000111
Whether the current solution is larger than a preset threshold value or not, if the current solution is smaller than the preset threshold value, the current solution d omega is obtained,
Figure BDA0003568173430000112
d kappa and d rho are respectively accumulated to omega, d rho obtained by the previous solution,
Figure BDA0003568173430000113
And k and p are used as the positioning angles after geometric correction. If the value is larger than the preset threshold value, according to the following steps: ω' ═ ω + d ω,
Figure BDA0003568173430000114
K '═ k + d κ and ρ' ═ ρ + d ρ, and are added to ω, ω and ρ obtained in the previous solution,
Figure BDA0003568173430000115
Kappa and rho are updated to obtain new omega
Figure BDA0003568173430000116
Kappa ', rho ', and new omega '
Figure BDA0003568173430000117
Taking kappa 'and rho' as initial values, and recalculating residual vector matrix
Figure BDA0003568173430000118
Iterate until in the residual vector matrix
Figure BDA0003568173430000119
Stopping iteration when the current d omega is smaller than a preset threshold value, and calculating the current d omega,
Figure BDA00035681734300001110
d kappa and d rho are respectively added to the parameters omega and d rho obtained by the previous calculation,
Figure BDA00035681734300001111
And k and p are used as the positioning angles after geometric correction.
In summary, according to the geometric correction method for the placement error of the unmanned airborne radar, the ground control points are distributed, the ground reflectors are used as the geometric control points, the error equation corresponding to the placement angle error of the unmanned airborne radar is constructed based on the principle that the distance residual error between the transmitting point of the laser radar and the ground geometric control points is minimum, the system error parameters of the placement angle are solved through the least square iterative calculation method, the optimal solution of the placement error of the airborne laser radar can be realized, the three-dimensional precision of the laser radar point cloud is further improved, and finally the application accuracy of the point cloud data in other aspects is improved.
The embodiment of the invention also provides a geometric correction device for the arrangement error of the unmanned airborne radar, which comprises the following components:
and the layout module is used for laying a plurality of reflective targets in the calibration field and laying a reference point and a check point outside the calibration field.
And the first acquisition module is used for acquiring the coordinates of each reflecting target based on the reference point and the check point.
And the second acquisition module is used for controlling the unmanned aerial vehicle carrying the laser radar to fly back and forth along a preset air route through a plurality of reflectors and acquiring attitude information and position information of the unmanned aerial vehicle.
And the third acquisition module is used for acquiring the slant distance and the beam splitting angle from the laser radar transmitting point to the ground reflecting point.
And the construction module is used for constructing an error equation according to the coordinates, the slant range, the beam splitting angle, the attitude information and the position information of the reflecting target based on the position deviation and the rotation geometric relation of the laser radar and the integrated navigation system.
The calculation module is used for solving an error equation to obtain a system error of the unmanned aerial vehicle radar installation angle; and the correction module is used for carrying out geometric correction on the installation angle by using the system error of the installation angle.
It should be noted that the detailed implementation details and the brought technical effects of the device embodiment portion and the method embodiment portion provided in the embodiments of the present invention are similar, and the device embodiment portion may refer to the method embodiment portion, which is not described herein again.
It will be appreciated by a person skilled in the art that features described in the various embodiments of the invention may be combined and/or coupled in a number of ways, even if such combinations or couplings are not explicitly described in the invention. In particular, various combinations and/or subcombinations of the features described in connection with the various embodiments of the invention may be made without departing from the spirit and teachings of the invention. All such combinations and/or associations fall within the scope of the present invention.
The above-mentioned embodiments are intended to illustrate the objects, technical solutions and advantages of the present invention in further detail, and it should be understood that the above-mentioned embodiments are only exemplary embodiments of the present invention, and are not intended to limit the present invention, and any modifications, equivalents, improvements and the like made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims (9)

1. A geometric correction method for a positioning error of an unmanned airborne radar comprises the following steps:
laying a plurality of reflecting marks in a calibration field, and laying a reference point and a check point outside the calibration field;
acquiring coordinates of each reflecting target based on the reference point and the check point;
controlling an unmanned aerial vehicle carrying a laser radar to fly back and forth along a preset route and pass through the plurality of reflectors, and acquiring attitude information and position information of the unmanned aerial vehicle;
acquiring the slant distance and the beam splitting angle from the laser radar transmitting point to the ground reflecting point;
based on the position deviation and rotation geometric relation of the laser radar and the integrated navigation system, constructing an error equation according to the coordinates of the reflecting target, the slant range, the beam splitting angle, the attitude information and the position information;
solving the error equation to obtain a system error of the unmanned airborne radar installation angle;
and geometrically correcting the installation angle by using the system error of the installation angle.
2. The method for geometric correction of unmanned airborne radar placement error of claim 1, wherein said obtaining coordinates of each reflectron based on said reference point and said checkpoint comprises:
and taking the reference point as a measuring station, taking the check point as an orientation point, and respectively acquiring the coordinates of each reflecting mark by adopting a total station.
3. The method of geometric correction of unmanned airborne radar placement error according to claim 1, wherein said obtaining attitude information and position information of said unmanned aerial vehicle comprises:
erecting a GPS base station on the reference point;
and taking the reference point as a base station, and carrying out integrated navigation calculation by adopting a GPS rear difference to obtain the attitude information and the position information.
4. The method of geometric correction of placement errors of an UAV according to claim 1, wherein said constructing a geometric verification model from said slant range, said beam splitting angle, said pose information, and said position information based on a position offset and rotation geometry of said LIDAR and integrated navigation system comprises:
and constructing the error equation by using the principle that the distance residual error of the slant distance is minimum.
5. The method of geometrically correcting an unmanned airborne radar placement error according to claim 1, wherein said error equation is:
Figure FDA0003568173420000021
wherein:
Figure FDA0003568173420000022
Figure FDA0003568173420000023
Figure FDA0003568173420000024
wherein, the first and the second end of the pipe are connected with each other,
Figure FDA0003568173420000025
is the distance residual of the slope distance rho, rho x 、ρ y 、ρ z The components of the skew distances in the x, y and z directions in a WGS-84 space rectangular coordinate system, rho x0 、ρ y0 、ρ z0 Are respectively rho x 、ρ y 、ρ z The initial value of (a) is,
Figure FDA0003568173420000026
the coordinates of the ith reflecting mark in the WGS-84 space rectangular coordinate system,
Figure FDA0003568173420000027
for the coordinates of the phase center of the antenna corresponding to the ith reflector in the WGS-84 rectangular space coordinate system, [ Delta X [ ] Ai_IMU ΔY Ai_IMU ΔZ Ai_IMU ] T Is the linear offset R of the laser emission reference center corresponding to the ith reflecting mark and the reference center of the inertial unit wgs84 A transformation matrix from a North-West high coordinate system to a WGS-84 space rectangular coordinate system; r ENU A transformation matrix from a north east high coordinate system to a north west high coordinate system; r H An instantaneous azimuth attitude angle rotation matrix of the inertial measurement unit; r P An instantaneous pitching attitude angle rotation matrix of the inertial measurement unit is obtained; r R For instantaneous roll attitude angle rotation matrix, R, of the inertial measurement unit M Is a rotation matrix of the arrangement angle of the reference center of the laser emission and the reference center of the inertia unit,
Figure FDA0003568173420000028
Kappa is an azimuth attitude angle, a pitch attitude angle and a roll attitude angle respectively, alpha is an included angle between the projection of the laser emission light path on the XOY surface of the body coordinate system and the positive direction of the X axis, beta is an included angle between the laser emission light path and the projection line of the laser emission light path on the XOY surface, and d omega,
Figure FDA0003568173420000029
d kappa is omega,
Figure FDA00035681734200000210
And d ρ is a correction value of the distance residual corresponding to ρ.
6. The method of geometrically correcting an unmanned airborne radar placement error according to claim 5, wherein said solving said error equation to obtain a systematic error of an unmanned airborne radar placement angle comprises:
solving for less than a preset threshold value
Figure FDA0003568173420000031
Corresponding d ω,
Figure FDA0003568173420000032
d κ, d ρ are the systematic errors of the setting angles.
7. The method for geometrically correcting the placement error of the unmanned airborne radar as claimed in claim 6, wherein said error equation is solved by means of iterative solution.
8. The method of geometrically correcting a placement error of an unmanned airborne radar according to claim 7, wherein said geometrically correcting said placement angle with said systematic error of said placement angle comprises:
the d omega obtained by current solution,
Figure FDA0003568173420000033
d kappa and d rho are respectively accumulated to omega, d rho obtained by the previous solution,
Figure FDA0003568173420000034
And k and p are used as the positioning angles after geometric correction.
9. A geometric correction device for positioning errors of an unmanned airborne radar comprises:
the layout module is used for laying a plurality of reflecting targets in a calibration field and laying a reference point and a check point outside the calibration field;
a first acquisition module for acquiring coordinates of each of the reflectors based on the reference points and the check points;
the second acquisition module is used for controlling the unmanned aerial vehicle carrying the laser radar to fly back and forth along a preset air route and pass through the plurality of reflectors, and acquiring attitude information and position information of the unmanned aerial vehicle;
the third acquisition module is used for acquiring the slant distance and the beam splitting angle from the laser radar transmitting point to the ground reflection point;
the building module is used for building an error equation according to the coordinate of the reflecting target, the slant distance, the beam splitting angle, the attitude information and the position information based on the position deviation and rotation geometric relation between the laser radar and the integrated navigation system;
the calculation module is used for solving the error equation to obtain the system error of the unmanned aerial vehicle radar installation angle;
and the correction module is used for carrying out geometric correction on the installation angle by utilizing the system error of the installation angle.
CN202210314982.6A 2022-03-28 2022-03-28 Geometric correction method and device for placement error of unmanned airborne radar Pending CN114859326A (en)

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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN116087925A (en) * 2023-04-07 2023-05-09 深圳煜炜光学科技有限公司 Method, device, equipment and storage medium for correcting quadrature error angle

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN116087925A (en) * 2023-04-07 2023-05-09 深圳煜炜光学科技有限公司 Method, device, equipment and storage medium for correcting quadrature error angle

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