CN116563394B - System and method for calibrating space coordinates of different-surface points - Google Patents
System and method for calibrating space coordinates of different-surface points Download PDFInfo
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- G01B—MEASURING LENGTH, THICKNESS OR SIMILAR LINEAR DIMENSIONS; MEASURING ANGLES; MEASURING AREAS; MEASURING IRREGULARITIES OF SURFACES OR CONTOURS
- G01B11/00—Measuring arrangements characterised by the use of optical techniques
- G01B11/002—Measuring arrangements characterised by the use of optical techniques for measuring two or more coordinates
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Abstract
The system comprises a calibration control unit and a calibration terminal, wherein the calibration terminal comprises a target and a plane mirror which are arranged on a target frame, and cameras and gesture measuring devices which are arranged on two sides of the target frame; the target comprises 4 coplanar points and 2 different-plane points; the target adjusting module of the calibration control unit determines target adjusting commands for sequentially adjusting targets into a gesture 1 and a gesture 2, and when the targets are in the gesture 1 and the gesture 2, the gesture measuring adjusting module of the calibration control unit respectively determines gesture measuring adjusting commands for adjusting gesture measuring devices, and after correspondingly adjusting the gesture measuring devices, the gesture measuring devices respectively acquire: azimuth angles of the gesture measuring device during gesture 1 and gesture 2, pixel coordinates of 4 coplanar points and 2 different-plane points; and a calculation module of the calibration control unit calculates the space coordinates of the different-plane points according to the 4 coplanar points and the measured values of the gesture measuring device. The method is simple and easy to implement, and the opposite and point three-dimensional space coordinates are accurately calibrated.
Description
Technical Field
The application relates to the technical field of optics, in particular to a system and a method for calibrating space coordinates of different surface points.
Background
In monocular camera measurement, the spatial coordinates of the cooperative targets in the internal reference and target of the camera are calibrated in advance, and the position and posture information of the camera coordinate system relative to the target coordinate system can be calculated by imaging the target through the camera. The internal parameters of the camera include the equivalent focal length (F x ,F y ) And principal point (C) x ,C y ). The target coordinate system is the space coordinate system where the cooperative target is located, and can be manually selected.
As shown in fig. 1, the target coordinate system is typically 4 coplanar points. Firstly, because 4 coplanar points can calculate the pose relation of a camera and a target, secondly, because the coplanar points are easy to process, the space coordinate relation of the coplanar points can be ensured by precision processing, and the space coordinate position precision of the coplanar points can be controlled to be 10-20 mu m according to the current precision machining lathe, so that the practicability can be met.
In practice, according to the principle of measurement by using a P4P monocular camera, monocular camera measurement is performed by using coplanar 4 points, a column in a 3×3 rotation matrix is calculated according to unit orthogonality of the matrix, instead of directly calculating elements of the column through an imaging equation, the calculation mode enables the measurement of a rotation angle Az of a target coordinate system around a Z axis (defined by a coordinate system of fig. 1), but the measurement precision of rotation angles Ax and Ay around X and Y axes is poor, the error reaches about ten times of the Az error, and in some monocular camera measurement requiring accurate measurement of Ax and Ay, the monocular measurement precision of the coplanar 4 points method cannot meet the requirement.
Through 6 different-surface points, monocular camera measurement is carried out, so that each element of the rotation matrix is solved independently, the measurement precision of Ax and Ay can be greatly improved, but the different-surface points cannot be precisely machined to ensure the position precision, if the space coordinate calibration is carried out after machining, the calibration means are limited, and a precise three-coordinate measuring instrument is needed.
Accordingly, the problems of the prior art are to be further improved and developed.
Disclosure of Invention
(one) object of the application: in order to solve the problems in the prior art, the application aims to provide a method for calibrating the space coordinates of the different-plane points by using a coplanar 4-point target and a theodolite to realize the three-dimensional space coordinate calibration of the different-plane points.
(II) technical scheme: in order to solve the technical problems, the technical proposal provides a system for calibrating the space coordinates of the different-surface points, which comprises a calibration control unit and a calibration terminal,
the calibration terminal comprises a target and a plane mirror which are arranged on a target frame, and further comprises cameras and gesture measuring devices which are respectively arranged on two sides of the target frame; the target is provided with 4 coplanar points, 2 different-surface points which are different from the 4 coplanar points are arranged on one side of the target, provided with the gesture measuring device, of the target, and the plane mirror is arranged on one side of the target, provided with the gesture measuring device;
the calibration control unit comprises an attitude measurement adjusting module, a target adjusting module, a camera adjusting module, a communication module, a storage module, a calculation module and an analysis module;
the target adjusting module determines target adjusting commands for sequentially adjusting targets to be in a gesture 1 and a gesture 2, the gesture measuring adjusting module respectively determines gesture measuring adjusting commands for adjusting the gesture measuring device when the targets are in the gesture 1 and the gesture 2, and the gesture measuring device respectively acquires after correspondingly adjusting the gesture measuring device: azimuth angle of attitude measuring device at attitude 1 is θ 1 And pixel coordinates (x) of 4 coplanar points, 2 non-planar points i ',y i '), i=1 to 6, and the coplanar points are i=1 to 4; azimuth angle of attitude measuring device at attitude 2 is θ 2 And pixel coordinates (x) of 4 coplanar points, 2 non-planar points i ,y i ) I=1 to 6, wherein the common plane point is i=1 to 4;
the calculation module calculates the space coordinates of the different-plane points after calculating the conversion matrix and the translation vector between the target coordinate system and the camera coordinate system according to the measured values of the 4 coplanar points and the gesture measuring device.
The system for calibrating the space coordinates of the different-plane points is characterized in that the centers of 4 coplanar points are set as coordinate origins, and the plane where the 4 points are positioned is an XY plane, namely Z=0; the 2 outliers are more than 0 from the XY plane.
The system for calibrating the space coordinates of the different-surface points comprises a camera frame, a camera control unit and a target frame, wherein the camera frame is arranged on one side of the target far away from the gesture measuring device, the camera control unit of the camera controls the X-direction level of a camera image, and the target frame is more than two thirds of the camera frame.
The system for calibrating the space coordinates of the different-plane points comprises a plane mirror normal and a Z axis, wherein an included angle formed by the plane mirror normal and the Z axis is smaller than 2 degrees.
The system for calibrating the space coordinates of the different-surface points comprises a gesture measuring device.
Before the target adjustment module determines a target adjustment command for adjusting a target to be a gesture 1, the gesture measurement adjustment module determines a first gesture measurement adjustment command according to a target gesture of the theodolite, and a gesture measurement control unit of the calibration terminal controls the theodolite to adjust according to the first gesture measurement adjustment command, so that the theodolite is close to a plane mirror and is subjected to auto-collimation imaging, and then the theodolite is leveled;
and the camera sends images of 4 coplanar points to the calibration control unit by adopting a P4P algorithm, the analysis module calculates the gesture of the target relative to the camera, and the target adjustment module obtains a first target adjustment command for adjusting the target to gesture 1 according to the gesture and gesture 1 of the current target relative to the camera.
The system comprises a target adjustment module, a calibration terminal, a target control unit and a target control unit, wherein the target adjustment module sends a first target adjustment command to the calibration terminal through the communication module, and the target control unit of the calibration terminal controls the target to be adjusted according to the first target adjustment command so that the target is in a gesture 1;
the attitude measurement adjustment module reads current attitude data of the theodolite in the analysis module, determines a second attitude measurement adjustment command according to a target attitude of the theodolite, sends the second attitude measurement adjustment command to the calibration terminal through the communication module, and the attitude measurement control unit of the calibration terminal controls the theodolite to adjust according to the second attitude measurement adjustment command, so that the theodolite is leveled after being close to the plane mirror and auto-collimated for imaging.
The system comprises a target adjusting module, a calibration terminal and a target control unit, wherein the target adjusting module determines a second target adjusting command according to a target gesture 1 and a target gesture 2, the target adjusting module sends the second target adjusting command to the calibration terminal through a communication module, and the target control unit of the calibration terminal rotates a target according to the second target adjusting command to enable the target to be in the gesture 2;
the attitude measurement adjustment module reads current attitude data of the theodolite in the analysis module, a third attitude measurement adjustment command is determined according to a target attitude of the theodolite, the attitude measurement adjustment module sends the third attitude measurement adjustment command to the calibration terminal through the communication module, and the attitude measurement control unit of the calibration terminal controls the theodolite to adjust according to the third attitude measurement adjustment command, so that the theodolite is leveled after being close to the plane mirror and auto-collimated for imaging.
The system for calibrating the space coordinates of the different surface points comprises a first component and a second component, wherein when a target is in a posture 1, A is as follows X 、A Z Is 0, A Y Is-30 degrees; when the target is in the posture 2, A X 、A Z Is 0, A Y 30 deg..
The calibration system comprises a calibration control unit and a calibration terminal, wherein the calibration terminal comprises a target and a plane mirror which are arranged on a target frame, and further comprises cameras and gesture measuring devices which are respectively arranged on two sides of the target frame; the target is provided with 4 coplanar points, 2 different-surface points which are different from the 4 coplanar points are arranged on one side of the target, provided with the gesture measuring device, of the target, and the plane mirror is arranged vertically below the 2 different-surface points; the calibration control unit comprises an attitude measurement adjusting module, a target adjusting module, a camera adjusting module, a communication module, a storage module, a calculation module and an analysis module, and comprises the following specific steps,
the target adjusting module determines a target adjusting command for adjusting the target to be in a posture 1, the posture measuring adjusting module determines a posture measuring adjusting command for adjusting the posture measuring device when the target is in the posture 1, and the posture measuring device acquires that the azimuth angle of the posture measuring device is theta at the moment after the posture measuring device is adjusted 1 And pixel coordinates (x) of 4 coplanar points, 2 non-planar points i ',y i '), i=1 to 6, and the coplanar points are i=1 to 4;
the target adjusting module determines a target adjusting command for adjusting the target to be in a posture 2, the posture measuring adjusting module determines a posture measuring adjusting command for adjusting the posture measuring device when the target is in the posture 2, and the posture measuring device acquires that the azimuth angle of the posture measuring device is theta at the moment after the posture measuring device is adjusted 2 And pixel coordinates (x) of 4 coplanar points, 2 non-planar points i ,y i ) I=1 to 6, wherein the common plane point is i=1 to 4;
the calculation module calculates the space coordinates of the different-plane points after calculating the conversion matrix and the translation vector between the target coordinate system and the camera coordinate system according to the measured values of the 4 coplanar points and the gesture measuring device.
(III) beneficial effects: the system and the method for calibrating the space coordinates of the different surface points can realize the accurate calibration of the three-dimensional space coordinates of the surface points without expensive calibration equipment such as a three-coordinate measuring instrument, are simple and feasible, can ensure the calibration precision, and have great engineering application value.
Drawings
FIG. 1 is a prior art monocular camera measurement schematic;
FIG. 2 is a schematic diagram of the structure of a system for calibrating the space coordinates of different surface points according to the application;
FIG. 3 is a schematic diagram of the structure of the calibration terminal of the present application;
FIG. 4 is a schematic diagram illustrating steps of a method for calibrating space coordinates of different surface points according to the present application;
101-target holder; 102 a camera; 103-an attitude measurement device; 104-plane mirror.
Detailed Description
The present application will be described in further detail with reference to the preferred embodiments, and more details are set forth in the following description in order to provide a thorough understanding of the present application, but it will be apparent that the present application can be embodied in many other forms than described herein, and that those skilled in the art may make similar generalizations and deductions depending on the actual application without departing from the spirit of the present application, and therefore should not be construed to limit the scope of the present application in the context of this particular embodiment.
The drawings are schematic representations of embodiments of the application, it being noted that the drawings are by way of example only and are not drawn to scale and should not be taken as limiting the true scope of the application.
The system for calibrating the space coordinates of the different surface points comprises a calibration control unit and a calibration terminal, wherein the calibration terminal sends measurement data to the calibration control unit, and the calibration control unit realizes coordinate calibration according to the measurement data.
As shown in fig. 2 and 3, the calibration terminal includes a target, the target includes a target frame 101, and the target is mounted on the target frame 101, and further includes cameras 102 and attitude measurement devices 103 respectively disposed on both sides of the target frame 101. The attitude measurement device comprises an attitude measurement control unit, and the attitude measurement control unit is used for carrying out attitude adjustment on the attitude measurement device. The camera 102 includes a camera control unit for performing an attitude adjustment of the camera 102. The target holder 101 includes a target control unit for achieving posture adjustment of a target.
The calibration control unit comprises an attitude measurement adjusting module, a target adjusting module, a camera adjusting module, a communication module, a storage module, a calculation module and an analysis module.
The calibration terminal performs data transmission with the calibration control unit through the communication module, stores measurement data of the calibration terminal in the storage module, and transmits attitude data of the attitude measurement device 103, the target and the camera to the analysis module in real time through the communication module. The gesture measurement adjustment module determines a gesture measurement adjustment command according to the current gesture and the target gesture of the gesture measurement device; the target adjusting module determines a target adjusting command according to the current gesture and the target gesture of the target; the camera adjustment module determines a camera adjustment command based on a current pose and a target pose of the camera. The analysis module is a coordination center of the calibration control unit and is used for calling the required information for each module of the calibration control unit. The calculation module calculates the coordinates of two different-surface points according to the coordinates of 4 same-surface points.
The target is provided with 4 coplanar points, and the 4 coplanar points on the target ensure the spatial position accuracy through mechanical processing. The spatial coordinates of the 4 coplanar points are known, and specifically, the center of the 4 points is usually set as the origin of coordinates, and the plane where the 4 points are located is the XY plane, i.e. z=0.
One side of the target setting posture measuring device 103 sets 2 cooperative targets: 2 out-of-plane points out-of-plane with the 4 in-plane points. The 2 different-surface points are arranged at positions different from the XY plane, are not shielded, and can be imaged by a camera.
To ensure measurement accuracy of Ax and Ay in monocular measurements, two cooperative targets: the 2 outliers are more than 0 from the XY plane. In the method, 2 different-surface points are required, because 6 points containing 2 different-surface points are used as targets, the accuracy of photogrammetry (compared with 4 points on the same plane) can be improved, and from the calibration perspective, the method can calibrate single different-surface points, namely 1 different-surface point and 4 coplanar points, and 2 different-surface points are not required to be used.
The other side of the target, i.e. the side opposite to the attitude measurement means 103, is provided with a camera, and the side provided with the camera 102 is the front of the target in the present application. The camera 102 is arranged right in front of the target, the camera control unit controls the X direction of the camera image to be horizontal, and the target occupies more than two thirds of the picture of the camera.
The plane mirror 104 is arranged at the rear of the target frame 101, namely, at one side where the gesture measuring device 103 is arranged, and can be fixed under the vertical positions or other positions of two cooperative targets (2 different-plane points) in a pasting mode, so that the theodolite can perform auto-collimation conveniently, and it is required to say that an included angle formed by the normal line of the plane mirror and the Z axis is smaller than 2 degrees, and the normal line of the plane mirror is most preferably parallel to the Z axis.
The attitude measurement device 103 preferably uses a theodolite, and the attitude measurement adjustment module reads current attitude data of the theodolite in the analysis module, and determines a first attitude measurement adjustment command according to a target attitude of the theodolite. The target pose of the theodolite at this time is: the plane mirror 104 that brings the theodolite close to the current position can be auto-collimated for imaging. The attitude measurement adjustment module sends a first attitude measurement adjustment command to the calibration terminal through the communication module, and the attitude measurement control unit of the calibration terminal controls the theodolite to adjust according to the first attitude measurement adjustment command, so that the theodolite can be leveled after being close to the plane mirror 104 for auto-collimation imaging.
And adopting a P4P algorithm to send images of the camera 102 on 4 coplanar points on an XY plane to the calibration control unit. The analysis module of the calibration control unit calculates the pose of the target relative to the camera 102 according to the images of the camera 102 on the 4 coplanar points on the XY plane. The target adjusting module determines a first target adjusting command according to the difference between the gesture of the target relative to the camera 102 and the gesture 1, the target adjusting module sends the first target adjusting command to the calibration terminal through the communication module, and the target control unit of the calibration terminal controls the target to adjust according to the first target adjusting command, so that the target is in the gesture 1. The P4P algorithm is an existing posture calibration algorithm model, and will not be described in detail herein.
Posture 1 is A X 、A Z Is 0, A Y Is-30 deg.. At this time it may be A X 、A Z About 0, A Y About-30, the closer the rotation angle is to-30, the better within the theodolite field of view.
A X 、A Z 、A Y Is an attitude angle, and represents that the target rotates A along the Z axis of the self coordinate system Z And then rotate A around the X axis X And then rotate A around the Y axis Y Then, the state parallel to the reference coordinate system (here, the camera coordinate system) is reached.
And the attitude measurement adjustment module reads the current attitude data of the theodolite in the analysis module, and determines a second attitude measurement adjustment command according to the target attitude of the theodolite. The target pose of the theodolite at this time is: the theodolite is made to be close to the plane mirror 104 in the target posture 1, so that the theodolite can be subjected to auto-collimation imaging. The gesture measurement adjustment module sends a second gesture measurement adjustment command to the calibration terminal through the communication module, and the gesture measurement control unit of the calibration terminal controls the theodolite to adjust according to the second gesture measurement adjustment command, so that the theodolite can be leveled after being close to the plane mirror 104 for auto-collimation imaging.
At this time, the theodolite auto-collimates the plane mirror, records that the azimuth angle of the theodolite is θ at this time 1 And pixel coordinates of 6 points (x i ',y i '), i=1 to 6, wherein the common plane point is i=1 to 4.
The target adjusting module determines a second target adjusting command according to the difference between the target gesture 1 and the gesture 2, the target adjusting module sends the second target adjusting command to the calibration terminal through the communication module, and the target control unit of the calibration terminal rotates the target according to the second target adjusting command to enable the target to be in the gesture 2.
Posture 2 is A X 、A Z Is 0, A Y 30 deg.. At this time it may be A X 、A Z About 0, A Y About 30, the closer the angle of rotation is to 30, the better within the theodolite field of view.
The attitude measurement adjustment module reads current attitude data of the theodolite in the analysis module (the attitude data of the theodolite when the target is in the attitude 1 and the theodolite is in auto-collimation imaging with the plane mirror), and determines a third attitude measurement adjustment command according to the target attitude of the theodolite. The target pose of the theodolite at this time is: the theodolite is made to be close to the plane mirror 104 in the target attitude 2, so that the theodolite can be subjected to auto-collimation imaging. The gesture measurement adjustment module sends a third gesture measurement adjustment command to the calibration terminal through the communication module, and the gesture measurement control unit of the calibration terminal controls the theodolite to adjust according to the third gesture measurement adjustment command, so that the theodolite can be leveled after being close to the plane mirror 104 for auto-collimation imaging.
At this time, the theodolite auto-collimates the plane mirror, records that the azimuth angle of the theodolite is θ at this time 2 And pixel coordinates of 6 points (x i ,y i ) I=1 to 6, wherein the common plane point is i=1 to 4.
The specific process of the calculation unit for the two outlier coordinates is as follows,
firstly, according to 4 coplanar points and theodolite measured values, a conversion matrix and a translation vector between a target coordinate system and a camera coordinate system are deduced:
the spatial coordinate system of the 4 coplanar points is ensured to be accurate by mechanical processing, is known and is marked asThe imaging pixel coordinates of the partner target point in the pose 1 and the partner target point in the pose 2 are respectively noted as (x) i ',y i ') and (x) i ,y i ) I=1 to 6. And (3) calculating:
k calculation procedure symbol
Note θ=θ 2 -θ 1 Then can be rememberedWherein (1)>
At pose 1, the spatial coordinates of the co-planar cooperative targets in pose 1 in pose 2 should be:
t is the translation vector between two coordinate systems
In the posture 2, the conversion relationship between the target coordinate system and the camera coordinate system is as follows:
r is a rotation matrix, and is recordedr i Are elements in the matrix.
The imaging formula is as follows:combining with the formula (3), and writing into a formula:
the conversion relation (3) between the target coordinate system and the camera coordinate system in the gesture 2 and the conversion relation (2) between the target coordinate system in the gesture 1 and the gesture 2 are as follows:
namely:
and (3) recording:then equation (5) can be written as:
similarly, the imaging formula:the method comprises the following steps:
r is calculated by the formula (4) and the formula (7) 0 ～r 8 、T X 、T Y 、T Z 、T X ′、T Y ′、T Z ' A total of 15 unknowns, by equation (4), can be solved:
substituting formula (8) into formula (7) includes:
the upper part containsThere are 6 unknowns in total.
Written in matrix form, there are:
the method can be solved as follows:
obviously, the transformation matrix:
based on the R column vectors as unit vectors, there are:
then according to s i Can be solved to obtain r 0 ～r 8 、T X 、T Y 、T Z 、T X ′、T Y ′、T Z 'total unknowns'.
Calculating the coordinates of the different surface points, and calculating the formula:
for unknown outliers (X, Y, Z), in pose 2, it is apparent that there are:
the method comprises the following steps:
in gesture 1:
order theThe method comprises the following steps:
the simultaneous (14), (16) comprises:
and (3) making:
then it can be solved that:
therefore, the calculation module obtains a new three-dimensional space coordinate of the different-surface point, and realizes the calibration of the three-dimensional space coordinate of the different-surface point.
The method for the space coordinates of the different surface points is applied to the space coordinates calibration system of the different surface points, as shown in fig. 4, and comprises the following specific steps,
the target adjusting module determines a target adjusting command for adjusting the target to be in a posture 1, the posture measuring adjusting module determines a posture measuring adjusting command for adjusting the posture measuring device when the target is in the posture 1, and the posture measuring device acquires that the azimuth angle of the posture measuring device is theta at the moment after the posture measuring device is adjusted 1 And pixel coordinates (x) of 4 coplanar points, 2 non-planar points i ',y i '), i=1 to 6, and the coplanar points are i=1 to 4;
the target adjusting module determines a target adjusting command for adjusting the target to be in a posture 2, the posture measuring adjusting module determines a posture measuring adjusting command for adjusting the posture measuring device when the target is in the posture 2, and the posture measuring device acquires that the azimuth angle of the posture measuring device is theta at the moment after the posture measuring device is adjusted 2 And pixel coordinates (x) of 4 coplanar points, 2 non-planar points i ,y i ) I=1 to 6, wherein the common plane point is i=1 to 4;
the calculation module calculates the space coordinates of the different-plane points after calculating the conversion matrix and the translation vector between the target coordinate system and the camera coordinate system according to the measured values of the 4 coplanar points and the gesture measuring device.
Different-surface point air conditionerThe inter-coordinate calibration system and method obtain a new three-dimensional space coordinate calibration method of the different-surface points according to the coplanarity 4-point and theodolite auto-collimation measurement, and the three-dimensional coordinates of the different-surface points calibrated by the method are used for monocular measurement by the different-surface 6-point method, so that A is obtained X 、A Y The measurement accuracy of (a) reaches A Z The same magnitude.
Compared with the prior art, the method comprises the following steps: the P4P measurement is used for calculating the rotation matrix and the translation vector of the gesture 1 and the gesture 2, the three-dimensional coordinates of the different surface points are calibrated according to the step (18), and then compared with the monocular measurement by the different surface 6 point method, the method in the prior art is used for measuring the A X 、A Y Stability and precision are far lower than monocular measurement precision performed after three-dimensional coordinates are calibrated by the method, and errors of the existing method are approximately 10 times larger than those of the method.
The foregoing is a description of a preferred embodiment of the application to assist those skilled in the art in more fully understanding the application. However, these examples are merely illustrative, and the present application is not to be construed as being limited to the descriptions of these examples. It should be understood that, to those skilled in the art to which the present application pertains, several simple deductions and changes can be made without departing from the inventive concept, and these should be considered as falling within the scope of the present application.
Claims (8)
1. A system for calibrating the space coordinates of different surface points is characterized by comprising a calibration control unit and a calibration terminal,
the calibration terminal comprises a target and a plane mirror which are arranged on a target frame, and further comprises cameras and gesture measuring devices which are respectively arranged on two sides of the target frame; the target is a target with 4 coplanar points, 2 different-surface points which are different from the 4 coplanar points are arranged on one side of the target, on which the gesture measuring device is arranged, of the target, and the plane mirror is arranged on one side of the target, on which the gesture measuring device is arranged;
the camera is arranged on one side of the target far away from the gesture measuring device, the camera control unit of the camera controls the X-direction level of the camera image, and the target occupies more than two thirds of the picture of the camera;
the calibration control unit comprises an attitude measurement adjusting module, a target adjusting module, a camera adjusting module, a communication module, a storage module, a calculation module and an analysis module;
the target adjusting module determines target adjusting commands for sequentially adjusting targets to be in a gesture 1 and a gesture 2, the gesture measuring adjusting module respectively determines gesture measuring adjusting commands for adjusting the gesture measuring device when the targets are in the gesture 1 and the gesture 2, and the gesture measuring device respectively acquires after correspondingly adjusting the gesture measuring device: azimuth angle of attitude measuring device at attitude 1 is θ 1 And pixel coordinates (x) of 4 coplanar points, 2 non-planar points i ',y i '), i=1 to 6, and the coplanar points are i=1 to 4; azimuth angle of attitude measuring device at attitude 2 is θ 2 And pixel coordinates (x) of 4 coplanar points, 2 non-planar points i ,y i ) I=1 to 6, wherein the common plane point is i=1 to 4;
the calculation module calculates a transformation matrix and a translation vector between a target coordinate system and a camera coordinate system according to the 4 coplanar points and the measured values of the gesture measuring device, and then calculates the space coordinates of the different-plane points;
the attitude measurement device comprises a theodolite;
the calculation process of the calculation module is as follows: according to the 4 coplanar points and theodolite measured values, a transformation matrix and a translation vector between a target coordinate system and a camera coordinate system are deduced: at pose 1, the spatial coordinates of 4 coplanar points in pose 2 represent the formula
Calculating a process symbol, wherein t is a translation vector between two coordinate systems;
in the attitude 2, the conversion relation of 4 coplanar points to a camera coordinate systemR is a rotation matrix, record->r i Is an element in the matrix;
from the imaging formulaWith equation (3), an imaging equation of 4 coplanar points in pose 2 is obtained
According to a conversion relation (3) of 4 coplanar point space coordinates in a target coordinate system and a camera coordinate system in the gesture 2 and a conversion relation (2) of the gesture 1 target coordinate system to the gesture 2, obtaining(6)，From the imaging formula->With equation (6), an imaging equation of 4 coplanar points in pose 1 is obtained
According to the imaging equation of 4 coplanar points in the gesture 1 and the imaging equation of 4 coplanar points in the gesture 2, a transformation matrix r of the gesture 2 to a camera coordinate system is calculated 0 ～r 8 Translation vector T of gesture 2 and gesture 1 to camera coordinate system X 、T Y 、T Z 、T X ′、T Y ′、T Z ' total unknowns;
conversion matrix r for converting gesture 2 into camera coordinate system 0 ～r 8 Posture 2 and posture 1 are oppositeTranslation vector T of machine coordinate system X 、T Y 、T Z 、T X ′、T Y ′、T Z ' and pixel coordinates of the outlier, and bringing the transformation relation of the outlier to the camera coordinate system and the imaging formula in the posture 2 to obtainAnd the conversion relation and imaging formula to the camera coordinate system in the gesture 1
θ＝θ 2 -θ 1 Three-dimensional coordinates of the outlier are calculated according to equations (13) and (15).
2. The system according to claim 1, wherein the centers of the 4 coplanar points are set as the origin of coordinates, and the plane in which the 4 points are located is the XY plane, i.e., z=0; the 2 outliers are more than 0 from the XY plane.
3. The system of claim 2, wherein the angle formed by the normal to the plane mirror and the Z-axis is less than 2 °.
4. The system for calibrating the space coordinates of the different surface points according to claim 3, wherein before the target adjustment module determines a target adjustment command for adjusting the target to be in a posture 1, the posture measurement adjustment module determines a first posture measurement adjustment command according to a target posture of the theodolite, and the posture measurement control unit of the calibration terminal controls the theodolite to adjust according to the first posture measurement adjustment command, so that the theodolite is leveled after being close to a plane mirror and being subjected to auto-collimation imaging;
and the camera sends images of 4 coplanar points to the calibration control unit by adopting a P4P algorithm, the analysis module calculates the gesture of the target relative to the camera, and the target adjustment module obtains a first target adjustment command for adjusting the target to gesture 1 according to the gesture and gesture 1 of the current target relative to the camera.
5. The system according to claim 4, wherein the target adjustment module sends a first target adjustment command to the calibration terminal through the communication module, and the target control unit of the calibration terminal controls the target to adjust according to the first target adjustment command so that the target is in a posture 1;
the attitude measurement adjustment module reads current attitude data of the theodolite in the analysis module, determines a second attitude measurement adjustment command according to a target attitude of the theodolite, sends the second attitude measurement adjustment command to the calibration terminal through the communication module, and the attitude measurement control unit of the calibration terminal controls the theodolite to adjust according to the second attitude measurement adjustment command, so that the theodolite is leveled after being close to the plane mirror and auto-collimated for imaging.
6. The system according to claim 5, wherein the target adjustment module determines a second target adjustment command according to the target gesture 1 and gesture 2, the target adjustment module sends the second target adjustment command to the calibration terminal through the communication module, and the target control unit of the calibration terminal rotates the target according to the second target adjustment command to enable the target to be in gesture 2;
the attitude measurement adjustment module reads current attitude data of the theodolite in the analysis module, a third attitude measurement adjustment command is determined according to a target attitude of the theodolite, the attitude measurement adjustment module sends the third attitude measurement adjustment command to the calibration terminal through the communication module, and the attitude measurement control unit of the calibration terminal controls the theodolite to adjust according to the third attitude measurement adjustment command, so that the theodolite is leveled after being close to the plane mirror and auto-collimated for imaging.
7. The system of claim 6, wherein a is X 、A Z Is 0, A Y Is-30 degrees; when the target is in the posture 2, A X 、A Z Is 0, A Y 30 °; a is that X 、A Y 、A Z Is the attitude angle.
8. The method is characterized by being applied to a different-surface point space coordinate calibration system, wherein the calibration system comprises a calibration control unit and a calibration terminal, the calibration terminal comprises a target and a plane mirror which are arranged on a target frame, and further comprises cameras and gesture measuring devices which are respectively arranged on two sides of the target frame; the target is a target with 4 coplanar points, 2 different-surface points which are different from the 4 coplanar points are arranged on one side of the target, on which the gesture measuring device is arranged, of the target, and the plane mirror is arranged on one side of the target, on which the gesture measuring device is arranged; the camera is arranged on one side of the target far away from the gesture measuring device, the camera control unit of the camera controls the X-direction level of the camera image, and the target occupies more than two thirds of the picture of the camera; the calibration control unit comprises an attitude measurement adjusting module, a target adjusting module, a camera adjusting module, a communication module, a storage module, a calculation module and an analysis module, and comprises the following specific steps,
the target adjusting module determines a target adjusting command for adjusting the target to be in a posture 1, the posture measuring adjusting module determines a posture measuring adjusting command for adjusting the posture measuring device when the target is in the posture 1, and the posture measuring device acquires that the azimuth angle of the posture measuring device is theta at the moment after the posture measuring device is adjusted 1 And pixel coordinates (x) of 4 coplanar points, 2 non-planar points i ',y i '), i=1 to 6, and the coplanar points are i=1 to 4;
the target adjusting module determines a target adjusting command for adjusting the target to be in a posture 2, and the posture measuring adjusting module determines a posture measuring adjusting command for adjusting the posture measuring device and adjusts when the target is in the posture 2After the attitude measurement device is integrated, the attitude measurement device obtains that the azimuth angle of the attitude measurement device is theta at the moment 2 And pixel coordinates (x) of 4 coplanar points, 2 non-planar points i ,y i ) I=1 to 6, wherein the common plane point is i=1 to 4;
the calculation module calculates a transformation matrix and a translation vector between a target coordinate system and a camera coordinate system according to the 4 coplanar points and the measured values of the gesture measuring device, and then calculates the space coordinates of the different-plane points;
the attitude measurement device comprises a theodolite;
the calculation process of the calculation module is as follows: according to the 4 coplanar points and theodolite measured values, a transformation matrix and a translation vector between a target coordinate system and a camera coordinate system are deduced: at pose 1, the spatial coordinates of 4 coplanar points in pose 2 represent the formula
Calculating a process symbol, wherein t is a translation vector between two coordinate systems;
in the attitude 2, the conversion relation of 4 coplanar points to a camera coordinate systemR is a rotation matrix, record->r i Is an element in the matrix;
from the imaging formulaWith equation (3), an imaging equation of 4 coplanar points in pose 2 is obtained
In the target coordinate system according to the posture 2The conversion relation (3) of the 4 coplanarity point space coordinates and the camera coordinate system and the conversion relation (2) of the gesture 1 target coordinate system to the gesture 2 are obtained(6)，From the imaging formula->With equation (6), an imaging equation of 4 coplanar points in pose 1 is obtained
According to the imaging equation of 4 coplanar points in the gesture 1 and the imaging equation of 4 coplanar points in the gesture 2, a transformation matrix r of the gesture 2 to a camera coordinate system is calculated 0 ～r 8 Translation vector T of gesture 2 and gesture 1 to camera coordinate system X 、T Y 、T Z 、T X ′、T Y ′、T Z ' total unknowns;
conversion matrix r for converting gesture 2 into camera coordinate system 0 ～r 8 Translation vector T of gesture 2 and gesture 1 to camera coordinate system X 、T Y 、T Z 、T X ′、T Y ′、T Z ' and the pixel coordinates of the outlier point, bring the outlier point into position
The conversion relation from the state 2 to the camera coordinate system and the imaging formula are obtainedAnd a conversion relation to a camera coordinate system at the time of the posture 1Imaging formula to obtain
θ＝θ 2 -θ 1 Three-dimensional coordinates of the outlier are calculated according to equations (13) and (15).
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