CN108088468B - System integration error checking method and device - Google Patents
System integration error checking method and device Download PDFInfo
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Abstract
The embodiment of the invention discloses a method and a device for verifying system integration errors, relates to measurement and remote sensing technologies, and can effectively verify the system integration errors. The verification method comprises the following steps: converting the attitude information recorded by the POS equipment to obtain an initial value of the image direct geo-location external orientation element, acquiring the external orientation element as a true value by using a single-chip rear intersection method, and resolving the external orientation element; checking the acquired multi-sensor data by adopting a position and attitude parameter based on POS equipment and an external orientation element interactive verification method based on GPS equipment auxiliary space three; and (4) directly positioning the initial value of the exterior orientation element by the aid of the images, directly and absolutely orienting by the aid of the control points, uniformly collecting field check points of the check field, and checking. The invention is suitable for checking the exterior orientation element.
Description
The application is a divisional application with the application date of 2016, month 07 and day 21, the application number of 201610579121.5 and the name of 'verification method and device based on POS equipment and digital aerial survey camera'.
Technical Field
The invention relates to measurement and remote sensing technologies, in particular to a method and a device for verifying system integration errors.
Background
An Inertial Measurement Unit (IMU)/Differential Global Positioning System (DGPS) assisted aerial photogrammetry technology belongs to an emerging technology internationally, is mature with technological progress and application practice, and is gradually applied to various fields of aerial remote sensing. The IMU/DGPS system has become an integral equipment for digital aerial cameras as well as airborne laser scanning systems. At present, a Positioning and Orientation System (POS) device is additionally arranged in an IMU/DGPS System to form an aerial remote sensing integrated System, attitude parameters of the IMU/DGPS System can be directly measured, and high-precision external Orientation elements required by mapping can be quickly obtained by jointly processing IMU and DGPS data.
However, the aviation remote sensing integrated system has systematic errors, and the sources of the systematic errors are as follows:
① accumulated drift error of IMU/DGPS system over time;
② systematic integration errors;
③ systematic time synchronization error;
④ errors caused by earth curvature;
⑤ atmospheric refractive index difference.
The first error belongs to inherent errors of the aerial remote sensing integrated system, and drift errors of the aerial remote sensing integrated system are mainly random errors inherent to a gyroscope and can be subjected to fitting processing through a corresponding polynomial model in corresponding POS data post-processing software;
the latter two terms belong to inherent errors of the traditional photogrammetry, and can directly refer to research results and empirical formulas of the traditional photogrammetry;
the second item and the third item belong to errors introduced by an integrated system, namely errors introduced by integrating a POS device and a digital aerial survey camera in the aerial remote sensing integrated system are called system integration errors. Wherein the content of the first and second substances,
the offset value (eccentricity component) of the outer orientation element composed of three corner elements and three line elements is a main factor causing the system integration error. The external orientation element is a parameter for describing a spatial coordinate value and a posture of the photographing center, wherein the three line elements are used for describing the spatial coordinate value of the photographing center; the other three corner elements are used to describe the spatial pose of the shot. Ideally, the IMU is typically tightly secured to the digital aerial camera while the POS device assists in aerial photogrammetry. The corresponding axes of the IMU body coordinate system and the digital aerial survey camera body coordinate system should be parallel, but due to the integrated installation, after the IMU is fixedly connected with the digital aerial survey camera, the corresponding axes of the two coordinate systems are practically impossible to be parallel, the included angle between the corresponding axes is called as an eccentric angle, the included angle is decomposed in three directions to form three angle elements, and the eccentric angle needs to be checked and corrected in practical application and is considered in coordinate conversion.
Variations in the curvature of the earth and the focal length in the azimuth elements within the digital aerial camera cause offset values for the line element components. The influence of the earth curvature is manifested in that the coordinate system of the mathematical model used in the photogrammetric block adjustment is not consistent with the coordinate system of the control point for determining the absolute spatial position of the block. Changes in aerial conditions cause changes in focal length and thus changes in aerial photogrammetry ground coordinates.
For the system time synchronization error, the flight speed of the aerial camera is generally 50-550 km/h. Since the flight speed is unlikely to change much for a short time, the linear interpolation error is assumed to be 1% of the POS observation epoch distance. For an airplane with the flight speed of 600km/h and an aviation remote sensing integrated system with the output frequency of 200Hz, the time synchronization error is about 0.8 cm. Thus, this order of magnitude is completely negligible for photogrammetry.
At present, no effective verification method exists for system integration errors introduced by integrating POS equipment and a digital aerial survey camera.
Disclosure of Invention
In view of this, embodiments of the present invention provide a method and an apparatus for verifying a system integration error, which can effectively verify the system integration error.
In a first aspect, an embodiment of the present invention provides a method for verifying a system integration error, including:
converting the attitude information recorded by the POS equipment to obtain an initial value of the image direct geo-location external orientation element, acquiring the external orientation element as a true value by using a single-chip rear intersection method, and resolving the external orientation element;
checking the acquired multi-sensor data by adopting a position and attitude parameter based on POS equipment and an external orientation element interactive verification method based on GPS equipment auxiliary space three;
using the images to directly and geographically locate the initial values of the exterior orientation elements and directly using the absolute orientation of the control points, uniformly collecting the field check points of the check field, and checking;
positioning and orienting by using the exterior orientation elements of the determined area;
positioning the orientation with the exterior orientation element of the region of interest comprises:
acquiring and verifying the attitude of a flight exposure point by utilizing the IMU attitude at the area measurement exposure time;
verifying the external orientation element of the flight image by using the verified attitude of the flight exposure point and the obtained eccentric angle element and eccentric line element;
performing DG precision verification by using external orientation elements of the verified flight images;
the posture information recorded by the POS equipment is converted to obtain an initial value of the image direct geo-location exterior orientation element, the exterior orientation element is obtained by a monolithic backward rendezvous method to serve as a true value, and the step of resolving the exterior orientation element comprises the following steps:
calculating an external orientation element true value of the digital aerial survey camera by performing space-three encryption on a ground calibration field;
calculating the angle element comparison of the digital aerial survey camera with the combined navigation, and calculating the eccentric angle and the eccentric distance by a least square method, wherein the eccentric angle is the included angle between corresponding axes of two coordinate systems after the IMU is fixedly connected with the digital aerial survey camera;
the eccentricity solution is as follows:
in the formula (I), the compound is shown in the specification,
in the formula (I), the compound is shown in the specification,
is XsThe mean value of (a);
correcting the calculated eccentric angle and eccentric distance to POS data of the whole measuring area, and calculating external orientation elements of the image of the whole measuring area;
the step of calculating the truth value of the exterior orientation element of the digital aerial survey camera by encrypting the ground calibration field through the space-three encryption comprises the following steps:
distributing a sufficient number of control points in a measuring area, and solving the exterior orientation elements of the image by using space-three encryption to serve as truth values of the exterior orientation elements;
the method is characterized in that enough control points are distributed in a measuring area, and the space-three encryption method for solving the external orientation element of the image comprises the following steps as the true value of the external orientation element:
processing the image to obtain an image of which the measuring area meets the requirement;
carrying out single-chip backward rendezvous on the acquired images;
acquiring coordinates of image points;
solving the image by utilizing space-three encryption to obtain an external orientation element true value of the checking flight image;
the exterior orientation elements of the space-three encrypted solved image comprise: and directly outputting the true value of the external orientation element of each image by sequentially utilizing the methods of internal orientation, relative orientation, absolute orientation and adjustment.
With reference to the first aspect, in a first implementation manner of the first aspect, the calculating the eccentricity angle and the eccentricity by a least square method, in comparison with calculating the angle element of the digital aerial camera by the integrated navigation, includes:
processing the obtained POS data, calculating the exposure time of the digital aerial survey camera, making a Mark file and importing the Mark file into integrated navigation post-processing software, and obtaining the IMU posture at the exposure time of a survey area and the Western's safety 80 coordinate of the IMU center by using the integrated navigation post-processing software;
acquiring longitude and latitude of a central origin of a ground auxiliary coordinate system;
constructing an error equation and solving the optimal estimation of the eccentric angle;
solving for the best estimate of eccentricity comprises:
acquiring the posture of a calibration exposure point by utilizing the IMU posture at the test area exposure time;
acquiring calibration control point coordinates;
and acquiring an eccentric angle element and an eccentric line element according to the posture of the calibration exposure point, the calibration control point coordinate and the external orientation element true value.
With reference to the first aspect, in a second implementation manner of the first aspect, the correcting the calculated eccentricity angle and the calculated eccentricity to the POS data of the entire survey area, and the calculating the external orientation element of the image of the entire survey area includes:
substituting the best estimation of the eccentric angle obtained by solving into a preset formula, and solving an external orientation angle element required by the measurement area by combining POS data;
solving the eccentricity and the eccentricity angle by utilizing the relation between the position parameters output by the combined navigation and the true values of the elements of the external orientation line;
and correcting the POS data of the calculated region by using the calculated eccentric angle and the eccentric distance to obtain the external orientation element of the calculated region.
In a second aspect, an embodiment of the present invention provides a system integration error checking apparatus, including: an exterior orientation element resolving module, a checking module and a positioning orientation module, wherein,
the external orientation element resolving module is used for converting attitude information recorded by the POS equipment to obtain an initial value of an image direct geo-location external orientation element, acquiring the external orientation element as a true value by using a single-chip rear intersection method and resolving the external orientation element;
the checking module is used for checking the acquired multi-sensor data by adopting a position and attitude parameter based on POS equipment and an external orientation element interactive verification method based on GPS equipment auxiliary space three;
the checking module is used for directly positioning the initial value of the exterior orientation element in a geographical mode by using the image and directly using the absolute orientation of the control point, uniformly collecting the field check points of the check field and checking;
the positioning and orientation module is used for positioning and orienting by utilizing the exterior orientation elements of the determined area;
positioning the orientation with the exterior orientation element of the region of interest comprises:
acquiring and verifying the attitude of a flight exposure point by utilizing the IMU attitude at the area measurement exposure time;
verifying the external orientation element of the flight image by using the verified attitude of the flight exposure point and the obtained eccentric angle element and eccentric line element;
performing DG precision verification by using external orientation elements of the verified flight images;
the exterior orientation element resolving module comprises: a true value calculating unit, an eccentricity calculating unit and an exterior orientation element calculating unit, wherein,
the truth value calculation unit is used for calculating the truth value of the exterior orientation element of the digital aerial survey camera by carrying out air-to-three encryption on the ground calibration field;
the eccentric angle distance calculation unit is used for comparing angle elements of the digital aerial survey camera calculated by the integrated navigation and calculating an eccentric angle and an eccentric distance by a least square method, wherein the eccentric angle is an included angle between corresponding axes of two coordinate systems after the IMU is fixedly connected with the digital aerial survey camera;
the eccentricity solution is as follows:
in the formula (I), the compound is shown in the specification,
in the formula (I), the compound is shown in the specification,
is XsThe mean value of (a);
the external orientation element calculation unit is used for correcting the calculated eccentric angle and the calculated eccentric distance into POS data of the whole measuring area and calculating the external orientation element of the image of the whole measuring area;
the true value calculation unit includes: an image acquisition subunit, an intersection subunit, a pixel coordinate acquisition subunit, and a true value calculation subunit, wherein,
the image acquisition subunit is used for processing the image and acquiring the image of which the measuring area meets the requirement;
the rendezvous subunit is used for rendezvousing the acquired image after the single piece;
the image point coordinate acquisition subunit is used for acquiring image point coordinates;
the true value calculation operator unit is used for solving the image by utilizing space-triplet encryption and acquiring the true value of the external orientation element of the checking flight image;
the exterior orientation elements of the space-three encrypted solved image comprise: and directly outputting the true value of the external orientation element of each image by sequentially utilizing the methods of internal orientation, relative orientation, absolute orientation and adjustment.
With reference to the second aspect, in a first implementation manner of the second aspect, the eccentricity calculation unit includes: a processing subunit, a latitude and longitude acquisition subunit, and an estimation subunit, wherein,
the processing subunit is used for processing the obtained POS data, calculating the exposure time of the digital aerial survey camera, manufacturing a Mark file, importing the Mark file into the integrated navigation post-processing software, and obtaining the IMU posture at the exposure time of the survey area and the Western-Ann 80 coordinate of the IMU center by using the integrated navigation post-processing software;
the longitude and latitude acquisition subunit is used for acquiring the longitude and latitude of the central origin of the ground auxiliary coordinate system;
the estimation subunit is used for constructing an error equation and solving the optimal estimation of the eccentric angle; solving for the best estimate of eccentricity comprises:
acquiring the posture of a calibration exposure point by utilizing the IMU posture at the test area exposure time;
acquiring calibration control point coordinates;
and acquiring an eccentric angle element and an eccentric line element according to the posture of the calibration exposure point, the calibration control point coordinate and the external orientation element true value.
With reference to the second aspect, in a second implementation manner of the second aspect, the external orientation element calculation unit includes: a first solving subunit, an eccentric angular distance obtaining subunit and a second solving subunit, wherein,
the first solving subunit is used for substituting the best estimation of the eccentric angle obtained by solving into a preset formula and solving the external orientation angle element required by the measurement area by combining POS data;
the eccentric angular distance obtaining subunit is used for solving the eccentric distance and the eccentric angle by utilizing the relationship between the position parameters output by the combined navigation and the true values of the elements of the external orientation line;
and the second solving subunit is used for correcting the calculated eccentric angle and the eccentric distance to the POS data of the calculated region and acquiring the external orientation element of the calculated region.
According to the system integration error calibration method and device provided by the embodiment of the invention, the attitude information recorded by the POS equipment is utilized, the initial value of the image direct geo-location external orientation element is obtained after conversion, the external orientation element is obtained by utilizing a single-chip rear intersection method and is used as the true value, and the external orientation element is solved; checking the acquired multi-sensor data by adopting a position and attitude parameter based on POS equipment and an external orientation element interactive verification method based on GPS equipment auxiliary space three; the images are used for directly positioning the initial values of the exterior orientation elements in a geographical mode and directly utilizing the absolute orientation of the control points, the field check points of the check field are uniformly collected and checked, and system integration errors can be effectively checked.
Drawings
In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to the drawings without creative efforts.
FIG. 1 is a schematic flow chart illustrating a method for verifying system integration errors according to an embodiment of the present invention;
fig. 2 is a schematic structural diagram of a calibration apparatus for system integration errors according to an embodiment of the present invention.
Detailed Description
Embodiments of the present invention will be described in detail below with reference to the accompanying drawings.
It should be understood that the described embodiments are only some embodiments of the invention, and not all embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
Fig. 1 is a schematic flow chart of a method for verifying a system integration error according to an embodiment of the present invention, as shown in fig. 1, the method according to the embodiment may include:
step 101, obtaining an initial value of an image direct geo-location external orientation element after conversion by using attitude information recorded by POS equipment, obtaining the external orientation element as a true value by using a single-chip rear intersection method, and resolving the external orientation element;
in this embodiment, the calibration of the relationship between the digital aerial survey camera and the IMU refers to the calibration of the eccentricity angle and the eccentricity. As an optional embodiment, the attitude information recorded by the POS device is converted to obtain an initial value of the image direct geo-location external orientation element, the external orientation element is obtained as a true value by a monolithic backward rendezvous method, and the resolving the external orientation element includes:
calculating an external orientation element true value of the digital aerial survey camera by performing space-three encryption on a ground calibration field;
comparing the angle elements with the angle elements of the digital aerial survey camera calculated by the combined navigation, and calculating the eccentric angle and the eccentric distance by a least square method;
and correcting the calculated eccentric angle and eccentric distance according to the POS data of the whole measuring area, and calculating the external orientation element of the image of the whole measuring area.
In this embodiment, a certain number of image control points need to be distributed on the calibration site, and an instrument RTK is needed. And dividing the data into POS data and image data according to the acquired data.
In this embodiment, in the system integration error, the solution of the eccentric angle and the eccentric component is a key technique for integrated system calibration, and the purpose of performing the integrated calibration is to obtain the integrated system error, that is, to solve the eccentric angle and the line element eccentric component. The method comprises the steps that a ground calibration field is encrypted through the air-to-three mode, and the true value of an exterior orientation element of a digital aerial survey camera is calculated; the specific process of calculating the eccentric angle and the eccentric distance by the least square method compared with the angle elements of the digital aerial survey camera calculated by the combined navigation is as follows:
after the IMU is fixedly connected with the digital aerial survey camera, the included angle between the corresponding axes of the two coordinate systems is an eccentric angle, and the included angle is decomposed in three directions to form three angle elements which are marked as ex、ey、ez。
The rotation matrix from the aerial photography instrument (digital aerial survey camera) body coordinate system (c) to the IMU body coordinate system (b) is determined by the fixed installation angle (eccentric angle) between the IMU and the digital aerial survey camera, as shown in formula 1.1:
in the formula (I), the compound is shown in the specification,
ex、ey、ezall are a tiny amount (< 3 degrees), therefore, the rotation matrix can adopt a differential rotation matrix, as shown in formula (1.2):
in this embodiment, how to establish a relationship between post-processing data of the aerial remote sensing integrated system and the photogrammetric external orientation element by using the rotation matrix composed of the eccentric angle elements is a key for system integration error calibration. According to the coordinate system conversion relation, constructing an expression (1.3):
in the formula (I), the compound is shown in the specification,
In the present embodiment, the first and second electrodes are,
can be obtained by solving the data and the existing inherent relationship, so if the rotation matrix consisting of the eccentricity angles can be determined, the
The exterior orientation angle element can be directly determined
In this embodiment, the eccentricity solution may be expressed by equation (1.4):
in the formula (I), the compound is shown in the specification,
in the formula (I), the compound is shown in the specification,
is XsIs measured.
And combining the true value of the external orientation element solved by the calibration field to obtain the eccentricity. Substituting the solved eccentricity into an equation (1.4) to obtain an element of the exterior orientation line of the survey area, namely a rotation matrix:
the exterior orientation element can be obtained from the exterior orientation line element and the exterior orientation angle element.
In this embodiment, the external orientation element obtained by the POS is corrected by the eccentricity angle and the line element eccentricity component (eccentricity) to obtain other image external orientation elements in the measurement area.
In this embodiment, calculating the truth value of the exterior orientation element of the digital aerial survey camera by encrypting the ground calibration field with space three times includes:
and arranging a sufficient number of control points in the measuring area, and solving the external orientation elements of the image by using the space-three encryption method to serve as the true values of the external orientation elements.
In this embodiment, the out-of-picture orientation element is solved by using a collinear conditional equation according to a certain number of reasonably distributed ground control points (coordinates of image points and ground points of the image points are known) within the image coverage range.
As an alternative embodiment, a sufficient number of control points are distributed in the survey area, and the space-three encryption method for solving the external orientation element of the image includes, as a true value of the external orientation element:
a01, processing the image to obtain an image with a measuring area meeting the requirement;
a02, carrying out single-chip rear intersection on the acquired images;
a03, acquiring coordinates of image points;
and A04, solving the image by using space-three encryption, and acquiring a true value of an external orientation element of the calibration flight image.
In this embodiment, as an optional embodiment, the calculating the eccentricity angle and the eccentricity by the least square method, in comparison with the calculating the angle element of the digital aerial survey camera by the integrated navigation, includes:
a11, processing the obtained POS data, calculating the exposure time of the digital aerial survey camera, making a Mark file, importing the Mark file into integrated navigation post-processing software, and obtaining the IMU posture at the measuring area exposure time and the Western-Ann 80 coordinate of the IMU center by using the integrated navigation post-processing software;
a12, acquiring longitude and latitude of a central origin of the ground auxiliary coordinate system;
and A13, constructing an error equation and solving the best estimation of the eccentric angle.
In this embodiment, solving the best estimate of the eccentricity angle includes:
b11, acquiring the posture of the calibration exposure point by using the IMU posture at the measurement area exposure time;
b12, acquiring calibration control point coordinates;
and B13, acquiring an eccentric angle element and an eccentric line element according to the posture of the calibration exposure point, the calibration control point coordinate and the external orientation element true value.
In this embodiment, as an optional embodiment, the step of correcting the calculated eccentricity angle and the calculated eccentricity by the POS data of the entire measurement area, and the step of calculating the external orientation element of the image of the entire measurement area includes:
a14, substituting the best estimation of the eccentric angle obtained by solving into a preset formula, and solving the external orientation angle element required by the measurement area by combining POS data;
a15, solving the eccentricity and eccentricity by using the relation between the position parameter output by the combined navigation and the true value of the external orientation line element;
and A16, correcting the POS data of the calculated measuring area by using the eccentric distance of the calculated eccentric angle, and acquiring the external orientation element of the calculated measuring area.
102, checking the acquired multi-sensor data by adopting a position and attitude parameter based on POS equipment and an external orientation element interactive verification method based on GPS equipment auxiliary space three;
and 103, directly positioning the initial value of the exterior orientation element by the aid of the images and directly utilizing the absolute orientation of the control points, uniformly acquiring the field check points of the check field, and checking.
In this embodiment, as an optional embodiment, the method further includes:
and arranging and orienting by utilizing the exterior orientation element of the determined area.
In this embodiment, as an optional embodiment, the positioning and orienting by using the exterior orientation element of the determined region includes:
acquiring and verifying the attitude of a flight exposure point by utilizing the IMU attitude at the area measurement exposure time;
verifying the external orientation element of the flight image by using the verified attitude of the flight exposure point and the obtained eccentric angle element and eccentric line element;
and performing DG precision verification by using the external orientation elements of the verified flight images.
The verification method based on the POS device and the digital aerial survey camera provided by the embodiment. The method can be used for direct geographic orientation (DG), further shortens the construction period of the interior industry and improves the working efficiency.
In this embodiment, the calibration data is data of flight in the north of the lake by using the SW-L irda system, and the calibration parameter calculation and verification steps are as follows:
1) and arranging a sufficient number of control points in the measuring region, wherein the image control points are in a Siemens 80 coordinate system. And (4) solving the external orientation element of the image by the space-three encryption as a true value.
In this step, the exterior orientation element of the space-three-encryption solution image includes: by sequentially utilizing the methods of internal orientation, relative orientation, absolute orientation and adjustment, the external orientation element (true value) of each image can be directly output, namely three line elements in the external orientation element: xs、YS、ZS。
2) And calculating the exposure time of the camera, and manufacturing a Mark file and importing the Mark file into integrated navigation software IE. And acquiring the IMU posture at the exposure time and the Western's 80 coordinate of the IMU center by utilizing the combined navigation post-processing software.
In this step, calculating the exposure time of the camera includes: the camera exposure time is based on GPS time, and the pulse signal of the camera exposure triggers the camera exposure on one hand and is recorded by the controller on the other hand. Only extraction with software is then required.
IMU attitude, and the X corresponding to the Western 80 coordinate of IMU centerb auxiliary、Yb auxiliary、Zb auxiliary。
3) Acquiring longitude and latitude of central origin of ground auxiliary coordinate system measuring area (L)0，B0)。
In the step, the longitude and latitude (L) of the central origin of the measuring area of the ground auxiliary coordinate system is obtained by utilizing the WGS-84 geodetic coordinates (L, B) recorded by the GPS0，B0)。
4) And constructing an error equation and solving the optimal estimation of the eccentric angle.
5) Substituting the eccentric angle obtained by resolving into a formula, and solving the external orientation angle element required by the measurement area by combining POS data.
In this step, the formula means
The POS data contains three corner elements and three line elements. Specifically three attitude angles of the IMU and three coordinates in space.
6) And solving the eccentricity and the eccentricity angle by utilizing the relation between the position parameters output by the combined navigation and the true values of the elements of the external orientation line.
7) And correcting POS data of the region to be measured by using the solved eccentric angle and eccentric distance to obtain the external orientation element of the region to be measured.
8) And (4) arranging and orienting by using the external orientation element of the determined area.
In this step, the corrected exterior orientation elements of each acquired image are used. Direct geographic orientation (DG) may be possible without a control point. The data is used as photogrammetry basic data for later data production.
Fig. 2 is a schematic structural diagram of a second system integration error checking apparatus according to an embodiment of the present invention, and as shown in fig. 2, the apparatus according to this embodiment may include: an exterior orientation element solution module 21, a check module 22, and a check module 23, wherein,
the external orientation element resolving module 21 is connected with the checking module 22, and the checking module 22 is also connected with the checking module 23.
The external orientation element calculation module 21 is configured to convert the attitude information recorded by the POS device to obtain an initial value of an image direct geo-location external orientation element, obtain the external orientation element as a true value by using a monolithic backward rendezvous method, and calculate the external orientation element;
in this embodiment, as an optional embodiment, the external orientation element resolving module 21 includes: a true value calculation unit, an eccentricity calculation unit, and an external orientation element calculation unit (not shown), wherein,
the true value calculation unit is connected with the eccentric angular distance calculation unit, and the eccentric angular distance calculation unit is also connected with the external orientation element calculation unit.
The truth value calculation unit is used for calculating the truth value of the exterior orientation element of the digital aerial survey camera by carrying out air-to-three encryption on the ground calibration field;
in this embodiment, as an optional embodiment, the true value calculation unit lays a sufficient number of control points in the measurement area, and the space-three encryption method for solving the external orientation element of the image as the true value of the external orientation element includes: an image acquisition subunit, an intersection subunit, a pixel coordinate acquisition subunit, and a true value calculation subunit, wherein,
the image acquisition subunit is used for processing the image and acquiring the image of which the measuring area meets the requirement;
the rendezvous subunit is used for rendezvousing the acquired image after the single piece;
the image point coordinate acquisition subunit is used for acquiring image point coordinates;
and the true value operator unit is used for solving the image by utilizing space-triplet encryption and acquiring the true value of the external orientation element of the checking and correcting flight image.
The eccentric angular distance calculation unit is used for comparing the angular elements of the digital aerial survey camera calculated by the integrated navigation and calculating an eccentric angle and an eccentric distance by a least square method;
in this embodiment, as an optional embodiment, the eccentricity angle calculation unit includes: a processing subunit, a latitude and longitude acquisition subunit, and an estimation subunit, wherein,
the processing subunit is connected with the longitude and latitude acquiring subunit, and the longitude and latitude acquiring subunit is also connected with the estimating subunit.
The processing subunit is used for processing the obtained POS data, calculating the exposure time of the digital aerial survey camera, manufacturing a Mark file, importing the Mark file into the integrated navigation post-processing software, and obtaining the IMU posture at the exposure time of the survey area and the Western-Ann 80 coordinate of the IMU center by using the integrated navigation post-processing software;
the longitude and latitude acquisition subunit is used for acquiring the longitude and latitude of the central origin of the ground auxiliary coordinate system;
the estimation subunit is used for constructing an error equation and solving the optimal estimation of the eccentric angle; solving for the best estimate of eccentricity comprises:
acquiring the posture of a calibration exposure point by utilizing the IMU posture at the test area exposure time;
acquiring calibration control point coordinates;
and acquiring an eccentric angle element and an eccentric line element according to the posture of the calibration exposure point, the calibration control point coordinate and the external orientation element true value.
And the external orientation element calculation unit is used for correcting the calculated eccentric angle and the calculated eccentric distance into POS data of the whole measuring area and calculating the external orientation element of the image of the whole measuring area.
In this embodiment, as an optional embodiment, the external orientation element calculating unit includes: a first solving subunit, an eccentric angular distance obtaining subunit and a second solving subunit, wherein,
the first solving subunit is connected with the eccentric angular distance obtaining subunit, and the eccentric angular distance obtaining subunit is also connected with the second solving subunit.
The first solving subunit is used for substituting the best estimation of the eccentric angle obtained by solving into a preset formula and solving the external orientation angle element required by the measurement area by combining POS data;
the eccentric angular distance obtaining subunit is used for solving the eccentric distance and the eccentric angle by utilizing the relationship between the position parameters output by the combined navigation and the true values of the elements of the external orientation line;
and the second solving subunit is used for correcting the calculated eccentric angle and the eccentric distance to the POS data of the calculated region and acquiring the external orientation element of the calculated region.
The checking module 22 is used for checking the acquired multi-sensor data by adopting a position and attitude parameter based on POS equipment and an external orientation element interactive verification method based on GPS equipment auxiliary space three;
and the checking module 23 is used for directly positioning the initial value of the exterior orientation element by the image in a geographical manner, directly utilizing the control point for absolute orientation, uniformly acquiring the field check point of the check yard and checking.
In this embodiment, as an optional embodiment, the apparatus further includes:
and arranging and orienting modules 24 for arranging and orienting by utilizing the exterior orientation elements of the determined regions.
In this embodiment, the placement and orientation module 24 is connected to the verification module 23. As an alternative embodiment, the positioning orientation using the exterior orientation element of the region of interest comprises:
acquiring and verifying the attitude of a flight exposure point by utilizing the IMU attitude at the area measurement exposure time;
verifying the external orientation element of the flight image by using the verified attitude of the flight exposure point and the obtained eccentric angle element and eccentric line element;
and performing DG precision verification by using the external orientation elements of the verified flight images.
The apparatus of this embodiment may be used to implement the technical solution of the method embodiment shown in fig. 1, and the implementation principle and the technical effect are similar, which are not described herein again.
It should be understood that portions of the present invention may be implemented in hardware, software, firmware, or a combination thereof.
The above description is only for the specific embodiment of the present invention, but the scope of the present invention is not limited thereto, and any changes or substitutions that can be easily conceived by those skilled in the art within the technical scope of the present invention are included in the scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the protection scope of the claims.
Claims (8)
1. A method for verifying system integration errors, comprising:
converting the attitude information recorded by the POS equipment to obtain an initial value of the image direct geo-location external orientation element, acquiring the external orientation element as a true value by using a single-chip rear intersection method, and resolving the external orientation element;
checking the acquired multi-sensor data by adopting a position and attitude parameter based on POS equipment and an external orientation element interactive verification method based on GPS equipment auxiliary space three;
using the images to directly and geographically locate the initial values of the exterior orientation elements and directly using the absolute orientation of the control points, uniformly collecting the field check points of the check field, and checking;
positioning and orienting by using the exterior orientation elements of the determined area;
positioning the orientation with the exterior orientation element of the region of interest comprises:
acquiring and verifying the attitude of a flight exposure point by utilizing the IMU attitude at the area measurement exposure time;
verifying the external orientation element of the flight image by using the verified attitude of the flight exposure point and the obtained eccentric angle element and eccentric line element;
performing DG precision verification by using external orientation elements of the verified flight images; the posture information recorded by the POS equipment is converted to obtain an initial value of the image direct geo-location exterior orientation element, the exterior orientation element is obtained by a monolithic backward rendezvous method to serve as a true value, and the step of resolving the exterior orientation element comprises the following steps:
calculating an external orientation element true value of the digital aerial survey camera by performing space-three encryption on a ground calibration field;
calculating the angle element comparison of the digital aerial survey camera with the combined navigation, and calculating the eccentric angle and the eccentric distance by a least square method, wherein the eccentric angle is the included angle between corresponding axes of two coordinate systems after the IMU is fixedly connected with the digital aerial survey camera;
the eccentricity solution is as follows:
in the formula (I), the compound is shown in the specification,
in the formula (I), the compound is shown in the specification,
is XSThe mean value of (a);
and correcting the calculated eccentric angle and eccentric distance according to the POS data of the whole measuring area, and calculating the external orientation element of the image of the whole measuring area.
2. Verification method according to claim 1,
the step of calculating the truth value of the exterior orientation element of the digital aerial survey camera by encrypting the ground calibration field through the space-three encryption comprises the following steps:
distributing a sufficient number of control points in a measuring area, and solving the exterior orientation elements of the image by using space-three encryption to serve as truth values of the exterior orientation elements;
the method is characterized in that enough control points are distributed in a measuring area, and the space-three encryption method for solving the external orientation element of the image comprises the following steps as the true value of the external orientation element:
processing the image to obtain an image of which the measuring area meets the requirement;
carrying out single-chip backward rendezvous on the acquired images;
acquiring coordinates of image points;
and (4) solving the image by utilizing space-three encryption to obtain an external orientation element true value of the checking flight image.
3. The verification method of claim 1, wherein said calculating the eccentricity angle and eccentricity by least squares, as compared to calculating the angular elements of the digital aerial survey camera by integrated navigation, comprises:
processing the obtained POS data, calculating the exposure time of the digital aerial survey camera, making a Mark file and importing the Mark file into integrated navigation post-processing software, and obtaining the IMU posture at the exposure time of a survey area and the Western's safety 80 coordinate of the IMU center by using the integrated navigation post-processing software;
acquiring longitude and latitude of a central origin of a ground auxiliary coordinate system;
constructing an error equation and solving the optimal estimation of the eccentric angle;
solving for the best estimate of eccentricity comprises:
acquiring the posture of a calibration exposure point by utilizing the IMU posture at the test area exposure time;
acquiring calibration control point coordinates;
and acquiring an eccentric angle element and an eccentric line element according to the posture of the calibration exposure point, the calibration control point coordinate and the external orientation element true value.
4. The verification method of claim 1, wherein correcting the calculated eccentricity and eccentricity to the POS data for the entire survey area, and wherein calculating the exterior orientation element of the image of the entire survey area comprises:
substituting the best estimation of the eccentric angle obtained by solving into a preset formula, and solving an external orientation angle element required by the measurement area by combining POS data;
solving the eccentricity and the eccentricity angle by utilizing the relation between the position parameters output by the combined navigation and the true values of the elements of the external orientation line;
and correcting the POS data of the calculated region by using the calculated eccentric angle and the eccentric distance to obtain the external orientation element of the calculated region.
5. A system integration error verifier device, comprising: an exterior orientation element resolving module, a checking module and a positioning orientation module, wherein,
the external orientation element resolving module is used for converting attitude information recorded by the POS equipment to obtain an initial value of an image direct geo-location external orientation element, acquiring the external orientation element as a true value by using a single-chip rear intersection method and resolving the external orientation element;
the checking module is used for checking the acquired multi-sensor data by adopting a position and attitude parameter based on POS equipment and an external orientation element interactive verification method based on GPS equipment auxiliary space three;
the checking module is used for directly positioning the initial value of the exterior orientation element in a geographical mode by using the image and directly using the absolute orientation of the control point, uniformly collecting the field check points of the check field and checking;
the positioning and orientation module is used for positioning and orienting by utilizing the exterior orientation elements of the determined area;
positioning the orientation with the exterior orientation element of the region of interest comprises:
acquiring and verifying the attitude of a flight exposure point by utilizing the IMU attitude at the area measurement exposure time;
verifying the external orientation element of the flight image by using the verified attitude of the flight exposure point and the obtained eccentric angle element and eccentric line element;
performing DG precision verification by using external orientation elements of the verified flight images; the exterior orientation element resolving module comprises: a true value calculating unit, an eccentricity calculating unit and an exterior orientation element calculating unit, wherein,
the truth value calculation unit is used for calculating the truth value of the exterior orientation element of the digital aerial survey camera by carrying out air-to-three encryption on the ground calibration field;
the eccentric angle distance calculation unit is used for comparing angle elements of the digital aerial survey camera calculated by the integrated navigation and calculating an eccentric angle and an eccentric distance by a least square method, wherein the eccentric angle is an included angle between corresponding axes of two coordinate systems after the IMU is fixedly connected with the digital aerial survey camera;
the eccentricity solution is as follows:
in the formula (I), the compound is shown in the specification,
in the formula (I), the compound is shown in the specification,
is XSThe mean value of (a);
6. The verification apparatus of claim 5,
the true value calculation unit includes: an image acquisition subunit, an intersection subunit, a pixel coordinate acquisition subunit, and a true value calculation subunit, wherein,
the image acquisition subunit is used for processing the image and acquiring the image of which the measuring area meets the requirement;
the rendezvous subunit is used for rendezvousing the acquired image after the single piece;
the image point coordinate acquisition subunit is used for acquiring image point coordinates;
and the true value operator unit is used for solving the image by utilizing space-triplet encryption and acquiring the true value of the external orientation element of the checking and correcting flight image.
7. The verification device according to claim 5, wherein the eccentricity-angle-distance calculation unit includes: a processing subunit, a latitude and longitude acquisition subunit, and an estimation subunit, wherein,
the processing subunit is used for processing the obtained POS data, calculating the exposure time of the digital aerial survey camera, manufacturing a Mark file, importing the Mark file into the integrated navigation post-processing software, and obtaining the IMU posture at the exposure time of the survey area and the Western-Ann 80 coordinate of the IMU center by using the integrated navigation post-processing software;
the longitude and latitude acquisition subunit is used for acquiring the longitude and latitude of the central origin of the ground auxiliary coordinate system;
the estimation subunit is used for constructing an error equation and solving the optimal estimation of the eccentric angle; solving for the best estimate of eccentricity comprises:
acquiring the posture of a calibration exposure point by utilizing the IMU posture at the test area exposure time;
acquiring calibration control point coordinates;
and acquiring an eccentric angle element and an eccentric line element according to the posture of the calibration exposure point, the calibration control point coordinate and the external orientation element true value.
8. The verification apparatus according to claim 5, wherein the outer orientation element calculation unit includes: a first solving subunit, an eccentric angular distance obtaining subunit and a second solving subunit, wherein,
the first solving subunit is used for substituting the best estimation of the eccentric angle obtained by solving into a preset formula and solving the external orientation angle element required by the measurement area by combining POS data;
the eccentric angular distance obtaining subunit is used for solving the eccentric distance and the eccentric angle by utilizing the relationship between the position parameters output by the integrated navigation and the true values of the elements of the external orientation line;
and the second solving subunit is used for correcting the calculated eccentric angle and the eccentric distance to the POS data of the calculated region and acquiring the external orientation element of the calculated region.
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| CN201710945299.1A Expired - Fee Related CN108279024B (en) | 2016-07-21 | 2016-07-21 | Verification method and device based on POS equipment and digital aerial survey camera |
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| CN106908042A (en) * | 2017-02-27 | 2017-06-30 | 广西翼界科技有限公司 | Aerophotogrammetry data screening method |
| CN106886037B (en) * | 2017-02-27 | 2018-07-27 | 立得空间信息技术股份有限公司 | POS data method for correcting error suitable for weak GNSS signal condition |
| CN107621627A (en) * | 2017-07-25 | 2018-01-23 | 河南省科学院地理研究所 | A kind of method and device of airborne lidar measuring instrument unit calibration |
| CN109269476A (en) * | 2018-12-12 | 2019-01-25 | 中国电子科技集团公司第二十七研究所 | Aerophotogrammetry system and method based on IMU/DGPS |
| CN110209847B (en) * | 2019-04-29 | 2021-09-28 | 中国科学院遥感与数字地球研究所 | Method and device for processing aviation remote sensing data machine in quasi-real time and storage medium |
| CN110736448A (en) * | 2019-11-19 | 2020-01-31 | 中国电建集团西北勘测设计研究院有限公司 | fixed wing unmanned aerial vehicle image control point-free three-dimensional modeling and mapping device and method |
| CN111208497A (en) * | 2020-04-20 | 2020-05-29 | 成都纵横融合科技有限公司 | Airborne laser radar system adjustment processing method |
| WO2022016356A1 (en) * | 2020-07-21 | 2022-01-27 | 中国科学院长春光学精密机械与物理研究所 | Method for calibrating high-precision interior and exterior orientation elements of mapping camera |
| CN111964693B (en) * | 2020-07-21 | 2022-03-22 | 中国科学院长春光学精密机械与物理研究所 | High-precision calibration method for internal and external orientation elements of surveying and mapping camera |
| CN112747773B (en) * | 2020-12-30 | 2022-12-06 | 中建八局第二建设有限公司 | Method for improving precision of gyroscope based on Allan variance and random polynomial |
| CN113008206B (en) * | 2021-03-29 | 2022-08-23 | 深圳飞马机器人科技有限公司 | Aerial triangulation mapping method and device, aircraft and computer readable storage medium |
| CN114279464A (en) * | 2021-12-14 | 2022-04-05 | 中国航空工业集团公司洛阳电光设备研究所 | Tower crane calibration field for calibrating errors of aerial survey camera and POS (Point of sale) integrated system |
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| CN1959343B (en) * | 2005-10-31 | 2011-02-16 | 北京师范大学 | Airborne height measurement technique of multiple angles imaging |
| CN101750619B (en) * | 2010-01-18 | 2012-07-11 | 武汉大学 | Method for directly positioning ground target by self-checking POS |
| CN102200575B (en) * | 2010-12-02 | 2013-06-12 | 南京大学 | Image ship detection method based on constant false alarm rate |
| CN102158662A (en) * | 2011-04-15 | 2011-08-17 | 中国科学院长春光学精密机械与物理研究所 | Image data transmission circuit of satellite-borne high-resolution CCD (Charge Coupled Device) camera |
| CN202092658U (en) * | 2011-04-25 | 2011-12-28 | 北京四维远见信息技术有限公司 | Outdoor calibration field for calibrating aerial digital camera |
| CN102506930A (en) * | 2011-11-10 | 2012-06-20 | 中国测绘科学研究院 | Checking device and method of aerial remote sensing integrated system |
| CN102538820B (en) * | 2011-12-13 | 2015-05-20 | 中国测绘科学研究院 | Calibration method of aerial remote sensing integrated system |
| KR101346323B1 (en) * | 2013-11-01 | 2014-01-02 | 주식회사 범아엔지니어링 | Method for self-calibration of non-metric digital camera using ground control point and additional parameter |
| CN104730539B (en) * | 2015-03-06 | 2017-10-03 | 河南城建学院 | A kind of small low-altitude light is infrared with laser radar integrated system |
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| CN108088467A (en) | 2018-05-29 |
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| CN106052718B (en) | 2017-11-14 |
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