Zero calibration method for installation of photoelectric tracking equipment

Abstract

The invention provides a photoelectric tracking equipment installation zero position calibration method, and relates to the technical field of installation zero position calibration. According to the method, the problem that the translation amount of a coordinate system cannot be directly and accurately calculated is solved by aiming at at least three kilometer-level close-range targets and using a multi-vector attitude determination and iteration combined calculation method. The non-coincidence amount of the original point of the photoelectric tracking equipment coordinate system and the original point of the radar coordinate system is compensated, the influence of a close-range target on calibration precision is eliminated, relative installation zero calibration of the photoelectric tracking equipment and the radar is achieved, a star aiming mode for calibration is avoided, and the method is wide in applicable weather and is slightly constrained by environmental conditions. According to the method, data registration is adopted, and calibration under the movable platform condition can be achieved. Abnormal value processing is carried out on the measurement data, and the influence of abnormal values on the calibration result is avoided.

Description

Technical Field

[0001] The invention relates to the technical field of installation zero position calibration, and in particular to an installation zero position calibration method for photoelectric tracking equipment. Background Art

[0002] The calibration of radar and optoelectronic tracking system usually adopts the "star aiming" method, which uses an infinitely far reference target to eliminate the parallax between optoelectronic tracking and radar. The disadvantage of the "star aiming" method is that it has high requirements for weather environment and is subject to greater environmental constraints, which greatly reduces the efficiency of zero calibration.

[0003] Among the currently disclosed methods that can replace "aiming at the stars", there is a method of building an optical path transfer reference between the photoelectric axes to be calibrated. This method is closely related to the construction of the optical path and the spatial position arrangement of the photoelectric axes to be calibrated, and the calibration device required is not universal, and it is difficult to meet the situation where the photoelectric axes to be calibrated are spaced far apart. There is also a method of calculating the installation zero position by comparing the side angle and the elevation angle, but the angular coupling between the azimuth, pitch and roll angles is not considered. The calculation method is equivalent and approximate, and more known conditions are required. It is only applicable to the situation where the coarse alignment of the calibrated devices has been completed and the angular deviation of the two coordinate systems is small.

[0004] In view of this, it is necessary to design an improved method for zero-position calibration of photoelectric tracking equipment installation to solve the above problems. Summary of the invention

[0005] The purpose of the present invention is to provide a method for zero-position calibration of photoelectric tracking equipment installation. The method adopts aiming at at least three close-range targets of several kilometers, and uses a calculation method combining multi-vector attitude determination and iteration to solve the problem that the translation of the coordinate system cannot be directly and accurately calculated, and the non-coincidence of the origin of the photoelectric tracking equipment coordinate system and the radar coordinate system is compensated, eliminating the influence of close-range targets on the calibration accuracy, realizing the relative installation zero-position calibration of the photoelectric tracking equipment and the radar, avoiding the calibration by the "star-aiming" method, and being applicable to a wide range of weather conditions and being less constrained by environmental conditions. The method adopts data registration, which can realize calibration under the condition of a moving platform; outlier processing is performed on the measured data to avoid the influence of outliers on the calibration results.

[0006] To achieve the above-mentioned purpose, the present invention provides a method for zero-position calibration of an optoelectronic tracking device, wherein the carrier of the radar and the optoelectronic tracking device is a moving platform, and the method comprises the following steps:

[0007] S1, establish the coordinate system: the radar coordinate system is the r system, the coordinate origin of the r system is the intersection D of the radar azimuth axis and the elevation axis; the optoelectronic tracking device coordinate system is the p system, the coordinate origin of the p system is the intersection B of the azimuth axis and the elevation axis of the optoelectronic tracking device; the optoelectronic tracking device reference coordinate system is the f system, the coordinate axes of the f system and the p system point in the same direction, and the coordinate origin of the f system coincides with the coordinate origin of the r system;

[0008] S2, select reference points: select targets within the measurement range of the optoelectronic tracking equipment and radar as reference points. The number of reference points selected shall be no less than 3;

[0009] S3, data acquisition: radar and optoelectronic tracking equipment are used to aim at the same reference point, and tracking and aiming data are acquired synchronously. Time synchronization is required before data acquisition;

[0010] Radar data including radar timestamp Radar azimuth Radar elevation angle

[0011] Photoelectric tracking device data including photoelectric tracking device timestamp Optoelectronic tracking device azimuth Photoelectric tracking device pitch angle Distance from reference point to photoelectric tracking device The distance from the reference point to the photoelectric tracking device is measured by the laser rangefinder on the photoelectric tracking device, and the subscripts i and j represent the jth set of data aimed at the i-th reference point respectively;

[0012] Use the same method to aim at the remaining reference points and record the data;

[0013] S4, data outlier processing: using box plot and 3σ method to eliminate abnormal data;

[0014] S5, data interpolation, based on the data timestamp, taking the radar data with low data rate as the benchmark, linear interpolation is used to complete the time alignment between the radar and the optoelectronic tracking device; the radar azimuth after alignment is obtained Radar pitch angle after registration Azimuth of the photoelectric tracking device after registration The pitch angle of the optoelectronic tracking device after registration Distance from reference point to photoelectric tracking device after registration The subscripts i and j respectively represent the jth set of interpolation data aiming at the i-th reference point;

[0015] S6, set initial values: set the rotation Euler angles ψ0, θ0, γ0 from the r system to the f system; then calculate the rotation attitude matrix by the rotation Euler angles ψ0, θ0, γ0 The initial value of is calculated as follows:

[0016]

[0017] S7, calculate the vector pointed by the reference point: calculate the coordinate value of the reference point in the reference coordinate system f of the optoelectronic tracking device, and the calculation formula is as follows:

[0018]

[0019] in, Refers to the vector from the origin B of the photoelectric tracking device coordinate system to the reference point T expressed in the p system; for Components in the x, y, and z directions;

[0020] Refers to the vector from the origin D of the radar coordinate system to the reference point T expressed in the f system; Refers to the vector from the radar coordinate origin D to the optoelectronic tracking device coordinate system origin B expressed in the f system;

[0021] It refers to the vector from the origin B of the photoelectric tracking device coordinate system to the reference point T expressed in the f system. Since the p system and the f system only have a translation relationship,

[0022] is the coordinate value of the origin B of the photoelectric tracking device coordinate system in the r system;

[0023] Directivity The unit vector of

[0024] The subscripts i and j correspond to the jth set of data at the i-th reference point.

[0025] Calculate the unit vector from the origin D of the radar coordinate system to the reference point T The calculation formula is as follows:

[0026]

[0027] in, for Components in the x, y, and z directions;

[0028] S8, calculate the rotation attitude matrix: use the multi-vector attitude method to calculate the rotation attitude matrix from the reference coordinate system f of the optoelectronic tracking device to the radar coordinate system r The calculation formula is as follows:

[0029]

[0030] A=UDV T

[0031]

[0032] In the above formula, A=UDV T Perform singular value decomposition on matrix A, m is the number of reference points, n is i is the number of data sets used for calculation of the i-th reference point;

[0033] Calculate the new rotation matrix The calculation formula is as follows:

[0034]

[0035] S9, iterative condition criterion: rotate the attitude matrix Converted into the rotation Euler angle ψ1, θ1, γ1, the attitude rotation matrix Converted into the rotation Euler angles ψ0, θ0, γ0, respectively calculate the rotation Euler angle differences Δψ, Δθ, Δγ, the calculation formula is as follows:

[0036] Δψ=|ψ1-ψ0|

[0037] Δθ=|θ1-θ0|

[0038] Δγ=|γ1-γ0|

[0039] S10, iteratively calculate the rotation attitude matrix: compare Δψ, Δθ, Δγ with the set threshold. When any one of Δψ, Δθ, Δγ is greater than the set threshold, a new rotation matrix is ​​used for assignment. Repeat the above steps S6 to S8 for iteration until the differences Δψ, Δθ, and Δγ of the rotation Euler angles of two adjacent groups are all less than the set threshold, and the iteration is completed; That is the final posture rotation matrix, which can be converted into the rotation Euler angle ψ0, θ0, γ0.

[0040] Furthermore, in step S10, the threshold is selected based on the calibration accuracy of the parameters (Δψ, Δθ, Δγ), and is usually set to 1 / 10 of the calibration accuracy.

[0041] Further, in step S2, the reference points are distributed with equal intervals.

[0042] Further, in step S2, the azimuth interval angle between the reference points is greater than or equal to 20°.

[0043] Further, in step S6, ψ0, θ0, and γ0 are roughly estimated according to the approximate installation relationship, or are directly assigned to zero. Roughly estimating according to the approximate installation relationship means that a relatively rough installation zero position (rough installation zero position) can be estimated based on the approximate installation relationship of the radar and the optoelectronic tracking device.

[0044] Furthermore, the coordinate systems r, p, and f all use the "front lower right" coordinate system.

[0045] The present invention also provides a method for zero-position calibration of an optoelectronic tracking device installation, wherein the carrier of the radar and the optoelectronic tracking device is a stationary platform, comprising the following steps:

[0046] S1, establish the coordinate system: the radar coordinate system is the r system, the coordinate origin of the r system is the intersection of the radar azimuth axis and the elevation axis; the optoelectronic tracking device coordinate system is the p system, the coordinate origin of the p system is the intersection of the azimuth axis and the elevation axis of the optoelectronic tracking device; the optoelectronic tracking device reference coordinate system is the f system, the coordinate axes of the f system and the p system point in the same direction, and the coordinate origin of the f system coincides with the coordinate origin of the r system;

[0047] S2, select reference points: select targets within the measurement range of the optoelectronic tracking equipment and radar as reference points. The number of reference points selected shall be no less than 3;

[0048] S3, data acquisition: radar and optoelectronic tracking equipment are used to aim at the same reference point, and tracking and aiming data are acquired synchronously. Time synchronization is required before data acquisition;

[0049] Radar data including radar timestamp Radar azimuth Radar elevation angle

[0050] Photoelectric tracking device data including photoelectric tracking device timestamp Optoelectronic tracking device azimuth Photoelectric tracking device pitch angle Distance from reference point to photoelectric tracking device The distance from the reference point to the photoelectric tracking device is measured by the laser rangefinder on the photoelectric tracking device, and the subscripts i and j represent the jth set of data aimed at the i-th reference point respectively;

[0051] Use the same method to aim at the remaining reference points and record the data;

[0052] S4, data outlier processing: using box plot and 3σ method to eliminate abnormal data;

[0053] S5, without data interpolation, takes the average value of the test data aimed at the i-th reference point to obtain the azimuth of the radar measurement data Radar measurement data elevation angle Optoelectronic tracking equipment measures data azimuth Photoelectric tracking equipment measures the elevation angle Distance from reference point to photoelectric tracking device

[0054] S6, set initial values: set the rotation Euler angles ψ0, θ0, γ0 from the r system to the f system; then calculate the rotation attitude matrix by the rotation Euler angles ψ0, θ0, γ0 The initial value of is calculated as follows:

[0055]

[0056] S7, calculate the vector pointed by the reference point: calculate the coordinate value of the reference point in the reference coordinate system f of the optoelectronic tracking device, and the calculation formula is as follows:

[0057]

[0058] in, Refers to the vector from the origin B of the photoelectric tracking device coordinate system to the reference point T expressed in the p system; for Components in the x, y, and z directions;

[0059] Refers to the vector from the origin D of the radar coordinate system to the reference point T expressed in the f system; Refers to the vector from the radar coordinate origin D to the optoelectronic tracking device coordinate system origin B expressed in the f system;

[0060] It refers to the vector from the origin B of the photoelectric tracking device coordinate system to the reference point T expressed in the f system. Since the p system and the f system only have a translation relationship,

[0061] is the coordinate value of the origin B of the photoelectric tracking device coordinate system in the r system;

[0062] Directivity The unit vector of

[0063] The subscript i corresponds to the data of the i-th reference point.

[0064] Calculate the unit vector from the origin D of the radar coordinate system to the reference point T The calculation formula is as follows:

[0065]

[0066] in, for Components in the x, y, and z directions;

[0067] S8, calculate the rotation attitude matrix: use the multi-vector attitude method to calculate the rotation attitude matrix from the reference coordinate system f of the optoelectronic tracking device to the radar coordinate system r The calculation formula is as follows:

[0068]

[0069] A=UDV T

[0070]

[0071] In the above formula, A=UDV TPerform singular value decomposition on matrix A, where m is the number of reference points;

[0072] Calculate the new rotation matrix The calculation formula is as follows:

[0073]

[0074] S9, iterative condition criterion: rotate the attitude matrix Converted into the rotation Euler angle ψ1, θ1, γ1, the attitude rotation matrix Converted into the rotation Euler angles ψ0, θ0, γ0, respectively calculate the rotation Euler angle differences Δψ, Δθ, Δγ, the calculation formula is as follows:

[0075] Δψ=|ψ1-ψ0|

[0076] Δθ=|θ1-θ0|

[0077] Δγ=|γ1-γ0|

[0078] S10, iterative calculation of the rotation attitude matrix: compare Δψ, Δθ, Δγ with the set threshold, and the threshold is selected according to the calibration accuracy of the parameters. When any one of Δψ, Δθ, Δγ is greater than the set threshold, a new rotation matrix is ​​used for assignment. Repeat the above steps S6 to S8 for iteration until the differences Δψ, Δθ, and Δγ of the rotation Euler angles of two adjacent groups are all less than the set threshold, and the iteration is completed; That is the final posture rotation matrix, which can be converted into the rotation Euler angle ψ0, θ0, γ0.

[0079] The beneficial effects of the present invention are:

[0080] 1) The zero-position calibration method for the photoelectric tracking device of the present invention adopts the observation of a short-distance target point instead of "aiming at the star", and the calibration can be carried out in weather with visibility exceeding 3 km, and is less restricted by the weather environment.

[0081] 2) The present invention combines multi-vector attitude determination with iteration, simplifies the solution of unknowns in the coordinate system translation calculation, and compensates for the influence of the non-coincidence of the two coordinate systems on the calibration result; the installation attitude zero position of the present invention is defined by a set of Euler angles, and there is no equivalence and approximation in the calibration and use processes, avoiding the influence of the coupling between angles, and can be applied to any installation. The installation zero position only needs to be calibrated for mathematical compensation, and there is no need to calibrate the physical object.

[0082] 3) The present invention adopts a multi-vector attitude determination calculation method based on singular value decomposition, and its calibration accuracy is better than the commonly used least squares method.

[0083] 4) The data acquisition of the present invention includes a timestamp, and data registration is used to obtain the measurement values ​​at the same time; then outlier detection and processing are used to eliminate the influence of outliers. BRIEF DESCRIPTION OF THE DRAWINGS

[0084] Figure 1 The present invention is a schematic flow chart of a method for installing a zero-position calibration for an optoelectronic tracking device.

[0085] Figure 2 It is a schematic diagram of the coordinate system in the present invention.

[0086] 1-Carrier, 2-Radar, 3-Optoelectronic tracking equipment. DETAILED DESCRIPTION

[0087] In order to make the purpose, technical solutions and advantages of the present invention more clear, the present invention is described in detail below with reference to the accompanying drawings and specific embodiments.

[0088] It should also be noted that, in order to avoid obscuring the present invention due to unnecessary details, only structures and / or processing steps closely related to the scheme of the present invention are shown in the drawings, while other details that are not closely related to the present invention are omitted.

[0089] In addition, it should be noted that the terms "comprises", "includes" or any other variations thereof are intended to cover non-exclusive inclusion, so that a process, method, article or apparatus that includes a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or apparatus.

[0090] Example 1

[0091] See also Figure 1 to Figure 2 As shown, in this embodiment, the carrier 1 of the radar 2 and the optoelectronic tracking device 3 is a moving platform. The electric axis of the radar 2 is replaced by the television axis on it, and both have been calibrated at the factory. The radar 2 can only measure the azimuth and pitch angle of the target through the television. The optoelectronic tracking device 3 includes a laser rangefinder, which can measure the target distance in addition to the azimuth and pitch angle of the target. The coordinate value of the optoelectronic tracking device 3 in the coordinate system of the radar 2 is known, and the coordinate value of the radar 2 in the coordinate system of the optoelectronic tracking device 3 is unknown.

[0092] The process of the zero position calibration method for installing the photoelectric tracking device of the present invention is as follows: Figure 1 As shown, the specific steps include:

[0093] S1, establish the coordinate system:

[0094] The radar coordinate system is the r system, and the coordinate origin of the r system is the intersection point D of the azimuth axis and the elevation axis of the radar 2;

[0095] The photoelectric tracking device coordinate system is the p system, and the coordinate origin of the p system is the intersection B of the azimuth axis and the pitch axis of the photoelectric tracking device 3;

[0096] The reference coordinate system of the photoelectric tracking device is the f system. The coordinate axes of the f system and the p system are in the same direction, and the origin of the f system coincides with the origin of the r system. The coordinate system uses the "front lower right" coordinate system.

[0097] S2, select reference points: select targets within the measurement range of the optoelectronic tracking device 3 and the radar 2 as reference points, and select no less than 3 reference points. The reference points should be distributed as evenly as possible, the angle interval should be as large as possible, and the azimuth interval should be no less than 20°.

[0098] S3, data recording: use radar 2 and optoelectronic tracking device 3 to aim at the same reference point, and synchronously record tracking and aiming data. Time synchronization is required before data recording.

[0099] Radar data contains radar timestamp Radar azimuth Radar elevation angle

[0100] Photoelectric tracking device data includes photoelectric tracking device timestamp Optoelectronic tracking device azimuth Photoelectric tracking device pitch angle Distance from target (reference point) to optoelectronic tracking device 3 The distance from the target to the optoelectronic tracking device 3 is measured by a laser rangefinder on the optoelectronic tracking device 3. Wherein, the subscripts i and j respectively represent the jth group of data aimed at the ith reference point.

[0101] Use the same method to aim at the remaining reference points and record the data.

[0102] S4, data outlier processing: box plot and 3σ method were used to eliminate abnormal data.

[0103] S5, data interpolation: according to the data timestamp, taking the radar data with low data rate as the benchmark, linear interpolation is used to complete the time alignment between radar 2 and optoelectronic tracking device 3. The radar azimuth after alignment is obtained Pitch angle after registration Azimuth of the photoelectric tracking device after registration Pitch angle after registration Distance from target to optoelectronic tracking device after registration The subscripts i and j respectively represent the jth group of interpolated data aimed at the ith reference point. In this embodiment, the interpolated data is shown in Table 1.

[0104] Table 1

[0105]

[0106] S6, set initial values: set the rotation Euler angles ψ0, θ0, γ0 from the r system to the f system; ψ0, θ0, γ0 are roughly estimated based on the rough installation relationship to obtain a rough installation zero position, or are directly assigned to zero. In this embodiment, they are directly assigned to zero.

[0107] Then the rotation attitude matrix is ​​calculated by rotating the Euler angles ψ0, θ0, γ0 The initial value of is calculated as follows:

[0108]

[0109] S7, calculate the vector pointed by the reference point: calculate the coordinate value of the reference point in the reference coordinate system f of the optoelectronic tracking device, and the calculation formula is as follows:

[0110]

[0111] in, Refers to the vector from the origin B of the photoelectric tracking device coordinate system to the reference point T expressed in the p system; for Components in the x, y, and z directions;

[0112] Refers to the vector from the origin D of the radar coordinate system to the reference point T expressed in the f system; Refers to the vector from the radar coordinate origin D to the optoelectronic tracking device coordinate system origin B expressed in the f system; It refers to the vector from the origin B of the photoelectric tracking device coordinate system to the reference point T expressed in the f system. Since the p system and the f system only have a translation relationship,

[0113]

[0114] is the coordinate value of the origin B of the photoelectric tracking device coordinate system in the r system;

[0115] Directivity The unit vector of

[0116] The subscripts i and j correspond to the jth set of data at the i-th reference point.

[0117] Calculate the unit vector from the origin D of the radar coordinate system to the reference point T The calculation formula is as follows:

[0118]

[0119] in, for Components in the x, y, and z directions;

[0120] In this embodiment They are 50m, -3.6m and 8.5m respectively.

[0121] S8, calculate the rotation attitude matrix: use the multi-vector attitude method to calculate the rotation attitude matrix from the reference coordinate system f of the optoelectronic tracking device to the radar coordinate system r The calculation formula is as follows:

[0122]

[0123] A=UDV T

[0124]

[0125] In the above formula, A=UDV T Perform singular value decomposition on matrix A, m is the number of reference points, n is i is the number of data sets used for calculation of the i-th reference point;

[0126] Calculate the new rotation matrix The calculation formula is as follows:

[0127]

[0128] S9, iterative condition criterion: rotate the attitude matrix Converted into the rotation Euler angle ψ1, θ1, γ1, the attitude rotation matrix Converted into the rotation Euler angles ψ0, θ0, γ0, respectively calculate the rotation Euler angle differences Δψ, Δθ, Δγ, the calculation formula is as follows:

[0129] Δψ=|ψ1-ψ0|

[0130] Δθ=|θ1-θ0|

[0131] Δγ=|γ1-γ0|

[0132] S10, iterative calculation of the rotation attitude matrix: compare Δψ, Δθ, Δγ with the set threshold value, which is selected based on the calibration accuracy of the parameters and is usually set to 1 / 10 of the calibration accuracy. When any one of Δψ, Δθ, Δγ is greater than the set threshold value, a new rotation matrix is ​​used for assignment. Repeat the above steps S6 to S8 for iteration until the differences Δψ, Δθ, and Δγ of the rotation Euler angles of two adjacent groups are all less than the set threshold, and the iteration is completed; That is the final posture rotation matrix, which can be converted into the rotation Euler angle ψ0, θ0, γ0.

[0133] In this embodiment, the threshold is set to 0.005°, and the iterative calculation results of ψ0, θ0, and γ0 are shown in Table 2.

[0134] Table 2

[0135] Iteration calculation sequence number <![CDATA[ψ0 / °]]> <![CDATA[θ0 / °]]> <![CDATA[γ0 / °]]> 1 19.7663 0.3324 0.6880 2 19.9791 0.3357 0.7093 3 19.9813 0.3358 0.7096

[0136] Example 2

[0137] Embodiment 2 provides a method for zero-position calibration of an optoelectronic tracking device. Unlike Embodiment 1, the carrier 1 of the radar 2 and the optoelectronic tracking device 3 is a stationary platform. The method for zero-position calibration of an optoelectronic tracking device is different from steps S5, S7, and S8 of Embodiment 1, and the other steps are the same. The details are as follows:

[0138] S1, establish the coordinate system:

[0139] The radar coordinate system is the r system, and the origin of the r system is the intersection of the azimuth axis and the elevation axis of the radar 2;

[0140] The photoelectric tracking device coordinate system is the p system, and the coordinate origin of the p system is the intersection of the azimuth axis and the pitch axis of the photoelectric tracking device 3;

[0141] The reference coordinate system of the photoelectric tracking device is the f system. The coordinate axes of the f system and the p system are in the same direction, and the origin of the f system coincides with the origin of the r system. The coordinate system uses the "front lower right" coordinate system.

[0142] S2, select reference points: select targets within the measurement range of the optoelectronic tracking device 3 and the radar 2 as reference points, and select no less than 3 reference points. The reference points should be distributed as evenly as possible, the angle interval should be as large as possible, and the azimuth interval should be no less than 20°.

[0143] S3, data recording: use radar 2 and optoelectronic tracking device 3 to aim at the same reference point, and synchronously record tracking and aiming data. Time synchronization is required before data recording.

[0144] Radar data contains radar timestamp Radar azimuth Radar elevation angle

[0145] Photoelectric tracking device data includes photoelectric tracking device timestamp Optoelectronic tracking device azimuth Photoelectric tracking device pitch angle Distance from target (reference point) to optoelectronic tracking device 3 The distance from the target to the optoelectronic tracking device 3 is measured by a laser rangefinder on the optoelectronic tracking device 3. Wherein, the subscripts i and j respectively represent the jth group of data aimed at the ith reference point.

[0146] Use the same method to aim at the remaining reference points and record the data.

[0147] In this embodiment, the admission data is shown in Table 3.

[0148] Table 3

[0149]

[0150] S4, data outlier processing: box plot and 3σ method were used to eliminate abnormal data.

[0151] S5, without data interpolation, takes the average value of the test data aimed at the i-th reference point to obtain the azimuth of the radar measurement data Radar measurement data elevation angle Optoelectronic tracking equipment measures data azimuth Photoelectric tracking equipment measures the elevation angle Distance from reference point to photoelectric tracking device

[0152] S6, set initial values: set the rotation Euler angles ψ0, θ0, γ0 from the r system to the f system; ψ0, θ0, γ0 are roughly estimated based on the approximate installation relationship, or are directly assigned to zero. In this embodiment, ψ0, θ0, γ0 are directly assigned to zero.

[0153] Then the rotation attitude matrix is ​​calculated by rotating the Euler angles ψ0, θ0, γ0 The initial value of is calculated as follows:

[0154]

[0155] S7, calculate the vector pointed by the reference point: calculate the coordinate value of the reference point in the reference coordinate system f of the optoelectronic tracking device, and the calculation formula is as follows:

[0156]

[0157] in, Refers to the vector from the origin B of the photoelectric tracking device coordinate system to the reference point T expressed in the p system; for Components in the x, y, and z directions;

[0158] Refers to the vector from the origin D of the radar coordinate system to the reference point T expressed in the f system; Refers to the vector from the radar coordinate origin D to the optoelectronic tracking device coordinate system origin B expressed in the f system;

[0159] It refers to the vector from the origin B of the photoelectric tracking device coordinate system to the reference point T expressed in the f system. Since the p system and the f system only have a translation relationship,

[0160] is the coordinate value of the origin B of the photoelectric tracking device coordinate system in the r system;

[0161] Directivity The unit vector of

[0162] The subscript i corresponds to the data of the i-th reference point.

[0163] Calculate the unit vector from the origin D of the radar coordinate system to the reference point T The calculation formula is as follows:

[0164]

[0165] in, for Components in the x, y, and z directions;

[0166] In this embodiment They are 25m, 5m and 3m respectively.

[0167] S8, calculate the rotation attitude matrix: use the multi-vector attitude method to calculate the rotation attitude matrix from the reference coordinate system f of the optoelectronic tracking device to the radar coordinate system r The calculation formula is as follows:

[0168]

[0169] A=UDV T

[0170]

[0171] In the above formula, A=UDV T Perform singular value decomposition on matrix A, where m is the number of reference points;

[0172] Calculate the new rotation matrix The calculation formula is as follows:

[0173]

[0174] S9, iterative condition criterion: rotate the attitude matrix Converted into the rotation Euler angle ψ1, θ1, γ1, the attitude rotation matrix Converted into the rotation Euler angles ψ0, θ0, γ0, respectively calculate the rotation Euler angle differences Δψ, Δθ, Δγ, the calculation formula is as follows:

[0175] Δψ=|ψ1-ψ0|

[0176] Δθ=|θ1-θ0|

[0177] Δγ=|γ1-γ0|

[0178] S10, iterative calculation of the rotation attitude matrix: compare Δψ, Δθ, Δγ with the set threshold value, which is selected based on the calibration accuracy of the parameters and is usually set to 1 / 10 of the calibration accuracy. When any one of Δψ, Δθ, Δγ is greater than the set threshold value, a new rotation matrix is ​​used for assignment. Repeat the above steps S6 to S8 for iteration until the differences Δψ, Δθ, and Δγ of the rotation Euler angles of two adjacent groups are all less than the set threshold, and the iteration is completed; That is the final posture rotation matrix, which can be converted into the rotation Euler angle ψ0, θ0, γ0.

[0179] In this embodiment, the threshold is set to 0.005°, and the iterative calculation results of ψ0, θ0, and γ0 are shown in Table 4.

[0180] Table 4

[0181] Iteration calculation sequence number <![CDATA[ψ0 / °]]> <![CDATA[θ0 / °]]> <![CDATA[γ0 / °]]> 1 29.8077 0.8100 0.4868 2 29.9778 0.8178 0.5074 3 29.9787 0.8179 0.5076

[0182] In summary, the present invention adopts aiming at at least three close-range targets of several kilometers, and uses a calculation method combining multi-vector attitude determination and iteration to solve the problem of being unable to directly and accurately calculate the translation of the coordinate system, and compensates for the misalignment of the origin of the photoelectric tracking device coordinate system and the radar coordinate system, eliminating the influence of close-range targets on the calibration accuracy, and realizing the relative installation zero-position calibration of the photoelectric tracking device and the radar, avoiding the calibration by the "star-aiming" method, and having a wide range of applicable weather conditions and little constraints from environmental conditions. The method adopts data registration, which can realize calibration under the condition of a moving platform; the measurement data is processed for outliers, avoiding the influence of outliers on the calibration results.

[0183] The above embodiments are only used to illustrate the technical solution of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solution of the present invention may be modified or replaced by equivalents without departing from the spirit and scope of the technical solution of the present invention.

Claims

1. A method for zero position calibration of photoelectric tracking equipment installation, characterized in that: The carrier of radar and optoelectronic tracking equipment is a moving platform, which includes the following steps: S1, establish the coordinate system: the radar coordinate system is the r system, and the origin of the r system is the intersection D of the radar azimuth axis and pitch axis; The coordinate system of the photoelectric tracking device is the p system, and the origin of the coordinate system of the p system is the intersection point B of the azimuth axis and the pitch axis of the photoelectric tracking device; The reference coordinate system of the photoelectric tracking device is the f system. The coordinate axes of the f system and the p system point in the same direction, and the origin of the f system coincides with the origin of the r system. S2, select reference points: select targets within the measurement range of the optoelectronic tracking equipment and radar as reference points. The number of reference points selected shall be no less than 3; S3, data acquisition: radar and optoelectronic tracking equipment are used to aim at the same reference point, and tracking and aiming data are acquired synchronously. Time synchronization is required before data acquisition; Radar data including radar timestamp Radar azimuth Radar elevation angle Photoelectric tracking device data including photoelectric tracking device timestamp Optoelectronic tracking device azimuth Photoelectric tracking device pitch angle Distance from reference point to photoelectric tracking device The distance from the reference point to the photoelectric tracking device is measured by the laser rangefinder on the photoelectric tracking device, and the subscripts i and j represent the jth set of data aimed at the i-th reference point respectively; Use the same method to aim at the remaining reference points and record the data; S4, data outlier processing: using box plot and 3σ method to eliminate abnormal data; S5, data interpolation, based on the data timestamp, taking the radar data with low data rate as the benchmark, linear interpolation is used to complete the time alignment between the radar and the optoelectronic tracking device; the radar azimuth after alignment is obtained Radar pitch angle after registration Azimuth of the photoelectric tracking device after registration The pitch angle of the optoelectronic tracking device after registration Distance from reference point to photoelectric tracking device after registration The subscripts i and j respectively represent the jth set of interpolation data aiming at the i-th reference point; S6, set initial values: set the rotation Euler angles ψ0, θ0, γ0 from the r system to the f system; then calculate the rotation attitude matrix by the rotation Euler angles ψ0, θ0, γ0 The initial value of is calculated as follows: S7, calculate the vector pointed by the reference point: calculate the coordinate value of the reference point in the reference coordinate system f of the optoelectronic tracking device, and the calculation formula is as follows: in, Refers to the vector from the origin B of the photoelectric tracking device coordinate system to the reference point T expressed in the p system; for Components in the x, y, and z directions; Refers to the vector from the origin D of the radar coordinate system to the reference point T expressed in the f system; Refers to the vector from the radar coordinate origin D to the optoelectronic tracking device coordinate system origin B expressed in the f system; It refers to the vector from the origin B of the photoelectric tracking device coordinate system to the reference point T expressed in the f system. Since the p system and the f system only have a translation relationship, is the coordinate value of the origin B of the photoelectric tracking device coordinate system in the r system; Directivity The unit vector of Subscripts i and j correspond to the jth set of data at the i-th reference point; Calculate the unit vector from the origin D of the radar coordinate system to the reference point T The calculation formula is as follows: in, for Components in the x, y, and z directions; S8, calculate the rotation attitude matrix: use the multi-vector attitude method to calculate the rotation attitude matrix from the reference coordinate system f of the optoelectronic tracking device to the radar coordinate system r The calculation formula is as follows: A=UDV T In the above formula, A=UDV T Perform singular value decomposition on matrix A, m is the number of reference points, n is i is the number of data sets used for calculation of the i-th reference point; Calculate the new rotation matrix The calculation formula is as follows: S9, iterative condition criterion: rotate the attitude matrix Converted into the rotation Euler angle ψ1, θ1, γ1, the attitude rotation matrix Converted into the rotation Euler angles ψ0, θ0, γ0, respectively calculate the rotation Euler angle differences Δψ, Δθ, Δγ, the calculation formula is as follows: Δψ=|ψ1-ψ0| Δθ=|θ1-θ0| Δγ=|γ1-γ0| S10, iteratively calculate the rotation attitude matrix: compare Δψ, Δθ, Δγ with the set threshold. When any one of Δψ, Δθ, Δγ is greater than the set threshold, a new rotation matrix is ​​used for assignment. Repeat the above steps S6 to S8 for iteration until the differences Δψ, Δθ, and Δγ of the rotation Euler angles of two adjacent groups are all less than the set threshold, and the iteration is completed; That is the final posture rotation matrix, which can be converted into the rotation Euler angle ψ0, θ0, γ0.

2. The method for zero-position calibration of photoelectric tracking equipment according to claim 1, characterized in that: In step S10 , the threshold is selected based on the calibration accuracy of Δψ, Δθ, and Δγ, and is set to 1 / 10 of the calibration accuracy.

3. The method for zero-position calibration of photoelectric tracking equipment according to claim 1, characterized in that: In step S2, the reference points are distributed with equal spacing.

4. The method for zero-position calibration of photoelectric tracking equipment according to claim 1, characterized in that: In step S2, the azimuth interval angle between the reference points is greater than or equal to 20°.

5. The method for zero-position calibration of photoelectric tracking equipment installation according to claim 1, characterized in that: In step S6, ψ0, θ0, and γ0 are roughly estimated based on the approximate installation relationship, or are directly assigned to zero.

6. The method for zero-position calibration of photoelectric tracking equipment according to claim 5, characterized in that: A rough estimate based on the approximate installation relationship means that the rough installation zero position can be estimated based on the approximate installation relationship of the radar and optoelectronic tracking equipment.

7. The method for zero-position calibration of photoelectric tracking equipment according to claim 1, characterized in that: The coordinate systems r, p, and f all use the "front lower right" coordinate system.

8. A method for zero position calibration of photoelectric tracking equipment installation, characterized in that: The carrier of radar and optoelectronic tracking equipment is a stationary platform, including the following steps: S1, establish the coordinate system: the radar coordinate system is the r system, and the origin of the r system is the intersection of the radar azimuth axis and the pitch axis; The coordinate system of the photoelectric tracking device is the P system, and the origin of the P system is the intersection of the azimuth axis and the pitch axis of the photoelectric tracking device; The reference coordinate system of the photoelectric tracking device is the f system. The coordinate axes of the f system and the p system point in the same direction, and the origin of the f system coincides with the origin of the r system. S2, select reference points: select targets within the measurement range of the optoelectronic tracking equipment and radar as reference points. The number of reference points selected shall be no less than 3; S3, data acquisition: radar and optoelectronic tracking equipment are used to aim at the same reference point, and tracking and aiming data are acquired synchronously. Time synchronization is required before data acquisition; Radar data including radar timestamp Radar azimuth Radar elevation angle Photoelectric tracking device data including photoelectric tracking device timestamp Optoelectronic tracking device azimuth Photoelectric tracking device pitch angle Distance from reference point to photoelectric tracking device The distance from the reference point to the photoelectric tracking device is measured by the laser rangefinder on the photoelectric tracking device, and the subscripts i and j represent the jth set of data aimed at the i-th reference point respectively; Use the same method to aim at the remaining reference points and record the data; S4, data outlier processing: using box plot and 3σ method to eliminate abnormal data; S5, without data interpolation, takes the average value of the test data aimed at the i-th reference point to obtain the azimuth of the radar measurement data Radar measurement data elevation angle Optical-electronic tracking equipment measures data azimuth Photoelectric tracking equipment measures the elevation angle Distance from reference point to photoelectric tracking device S6, set initial values: set the rotation Euler angles ψ0, θ0, γ0 from the r system to the f system; then calculate the rotation attitude matrix by the rotation Euler angles ψ0, θ0, γ0 The initial value of is calculated as follows: S7, calculate the vector pointed by the reference point: calculate the coordinate value of the reference point in the reference coordinate system f of the optoelectronic tracking device, and the calculation formula is as follows: in, Refers to the vector from the origin B of the photoelectric tracking device coordinate system to the reference point T expressed in the p system; for Components in the x, y, and z directions; Refers to the vector from the origin D of the radar coordinate system to the reference point T expressed in the f system; Refers to the vector from the radar coordinate origin D to the optoelectronic tracking device coordinate system origin B expressed in the f system; It refers to the vector from the origin B of the photoelectric tracking device coordinate system to the reference point T expressed in the f system. Since the p system and the f system only have a translation relationship, is the coordinate value of the origin B of the photoelectric tracking device coordinate system in the r system; Directivity The unit vector of Subscript i corresponds to the data of the i-th reference point; Calculate the unit vector from the origin D of the radar coordinate system to the reference point T The calculation formula is as follows: in, for Components in the x, y, and z directions; S8, calculate the rotation attitude matrix: use the multi-vector attitude method to calculate the rotation attitude matrix from the reference coordinate system f of the optoelectronic tracking device to the radar coordinate system r The calculation formula is as follows: A=UDV T In the above formula, A=UDV T Perform singular value decomposition on matrix A, where m is the number of reference points; Calculate the new rotation matrix The calculation formula is as follows: S9, iterative condition criterion: rotate the attitude matrix Converted into the rotation Euler angle ψ1, θ1, γ1, the attitude rotation matrix Converted into the rotation Euler angles ψ0, θ0, γ0, respectively calculate the rotation Euler angle differences Δψ, Δθ, Δγ, the calculation formula is as follows: Δψ=|ψ1-ψ0| Δθ=|θ1-θ0| Δγ=|γ1-γ0| S10, iteratively calculate the rotation attitude matrix: compare Δψ, Δθ, Δγ with the set threshold. When any one of Δψ, Δθ, Δγ is greater than the set threshold, a new rotation matrix is ​​used for assignment. Repeat the above steps S6 to S8 for iteration until the differences Δψ, Δθ, and Δγ of the rotation Euler angles of two adjacent groups are all less than the set threshold, and the iteration is completed; That is the final posture rotation matrix, which can be converted into the rotation Euler angle ψ0, θ0, γ0.

9. The method for zero-position calibration of photoelectric tracking equipment installation according to claim 1, characterized in that: In step S10 , the threshold is selected based on the calibration accuracy of Δψ, Δθ, and Δγ, and is set to 1 / 10 of the calibration accuracy.

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