Intersection measurement system and method based on four-station configuration

Abstract

The invention relates to a rendezvous measurement system, in particular to a rendezvous measurement system and method based on a four-station configuration, and solves the technical problem that an existing rendezvous measurement system of a two-station configuration cannot meet target positioning in a limit rendezvous angle state. According to the intersection measurement system based on the four-station configuration, four photoelectric tracking and measuring devices are distributed in a square shape, the baseline distance A between every two adjacent photoelectric tracking and measuring devices is equal to # imgabs0 # X, and X is a preset target observation distance; at the same observation moment, the four photoelectric tracking and measuring devices cooperatively observe a target, and the intersection angle between the two adjacent photoelectric tracking and measuring devices is calculated through the first photoelectric tracking and measuring device, so that compared with a traditional two-station configuration which only has one set of intersection angles, four sets of intersection angles can be obtained, and the optimal selection of the intersection angles can be realized according to the intersection angle selection principle. And a group of data of the photoelectric tracking and measuring equipment with the best positioning precision is selected for intersection positioning, so that the target positioning precision and the measurable working condition coverage rate are improved.

Description

Technical Field

[0001] The present invention relates to an intersection measurement system, and in particular to an intersection measurement system and method based on a four-station configuration. Background Art

[0002] Intersection measurement is a measurement method that uses the spatial position between stations and the target line of sight to determine the data to calculate the position and movement speed information of the space target. As an important method for rapid positioning of space targets, it has the advantages of low algorithm complexity and high real-time positioning accuracy. Among them, the intersection measurement method based on dual stations is more commonly used. It uses the line of sight determination data and station coordinates of the two measuring stations to achieve target positioning. The main factors affecting its positioning ability include: the measurement accuracy of the line of sight determination data, the observed intersection angle, the accuracy of the station location, the time error between the stations, etc. Among them, the impact of the intersection angle on the positioning accuracy is relatively more complicated. The relationship between the intersection angle and the positioning error is as follows: Figure 2 As shown in FIG, when the intersection angle is 30° to 150°, the positioning accuracy is relatively high. As the intersection angle approaches 0° or 180°, the positioning accuracy becomes lower and may even fail to meet actual application requirements.

[0003] The intersection angle is closely related to the site layout. It is determined by the geometric configuration of the measuring station and the target. Common geometric distributions include Figure 1 As shown in a, the positioning accuracy in this case is better. The other two more extreme geometric distributions are Figure 1 b and Figure 1 As shown in c, Figure 1 The intersection angle of the sight lines of the two measuring stations in b is close to 180°. Figure 1 In figure c, the intersection angle of the two measuring stations' sight lines is close to 0°, and the positioning accuracy in both cases is very poor. Currently, the dual-station intersection positioning method has certain limitations. In the case of poor geometric configuration, the target positioning of the two-station intersection cannot meet the needs of practical applications. Summary of the Invention

[0004] The purpose of the present invention is to solve the technical problem that the existing two-station intersection measurement system cannot meet the target positioning requirements under extreme intersection angles, and to provide a four-station intersection measurement system and method.

[0005] In order to achieve the above-mentioned object of the invention, the present invention provides the following technical solutions:

[0006] A rendezvous measurement system based on a four-station configuration is special in that it comprises four photoelectric tracking and measuring devices, namely a first photoelectric tracking and measuring device to a fourth photoelectric tracking and measuring device;

[0007] The first to fourth photoelectric tracking and measuring devices are distributed in a square, and the first photoelectric tracking and measuring device is electrically connected to the second photoelectric tracking and measuring device, the third photoelectric tracking and measuring device, and the fourth photoelectric tracking and measuring device respectively;

[0008] Define the distance between two adjacent photoelectric tracking and measuring devices as the baseline distance A, then A= X,

[0009] Where: X is the preset target observation distance.

[0010] Furthermore, the first photoelectric tracking and measuring device includes a tracking and image processing module and a positioning module; the second photoelectric tracking and measuring device, the third photoelectric tracking and measuring device and the fourth photoelectric tracking and measuring device include a tracking and image processing module;

[0011] The tracking and image processing module is electrically connected to the positioning module, the tracking and image processing module is used for tracking the target, extracting coordinates and calculating angular trajectory, and the positioning module is used for calculating the three-dimensional trajectory and speed of the target in real time;

[0012] The positioning module of the first photoelectric tracking and measuring device is electrically connected to the tracking and image processing modules of the second photoelectric tracking and measuring device, the third photoelectric tracking and measuring device, and the fourth photoelectric tracking and measuring device, respectively.

[0013] The present invention also provides a four-station configuration-based intersection measurement method, which uses the above-mentioned four-station configuration-based intersection measurement system, and is special in that it includes the following steps:

[0014] S1. Arrange the first to fourth photoelectric tracking and measuring devices in a square distribution, and set the baseline distance A between the first to fourth photoelectric tracking and measuring devices according to the preset target observation distance X, so that A= X;

[0015] S2, the first to fourth photoelectric tracking and measuring devices extract the coordinates of the target in the image in real time and calculate the target angular trajectory, and the second to fourth photoelectric tracking and measuring devices send their respective station coordinates and calculated target angular trajectory to the first photoelectric tracking and measuring device;

[0016] S3. The first photoelectric tracking and measuring device calculates the intersection angle between two adjacent photoelectric tracking and measuring devices using the target angular trajectory measured by the four photoelectric tracking and measuring devices;

[0017] S4. Selecting a pair of optoelectronic tracking and measuring devices with an optimal intersection angle, wherein the imaging time of the optoelectronic tracking and measuring devices includes a fixed deviation, maintaining the angular trajectory of one optoelectronic tracking and measuring device unchanged, and performing Lagrangian interpolation processing on the target angular trajectory of the other optoelectronic tracking and measuring device based on the imaging time of the optoelectronic tracking and measuring device with the unchanged angular trajectory;

[0018] S5. Using the target angular trajectory obtained after Lagrange interpolation and the site coordinates of the two optoelectronic tracking and measurement devices, the three-dimensional trajectory and velocity of the target are obtained through intersection calculation;

[0019] S6. Repeat steps S2 to S5 to complete the target intersection measurement based on the four-station configuration within the specified time period.

[0020] Furthermore, step S2 is specifically as follows: the tracking and image processing modules of the first photoelectric tracking and measuring device to the fourth photoelectric tracking and measuring device extract the coordinates of the target in the image in real time and calculate the target angular trajectory, and the second photoelectric tracking and measuring device to the fourth photoelectric tracking and measuring device send their respective station coordinates and the calculated target angular trajectory to the positioning module of the first photoelectric tracking and measuring device.

[0021] Furthermore, step S3 is specifically as follows: the positioning module of the first photoelectric tracking and measuring device uses the target angle trajectory calculated by the tracking and image processing modules of the four photoelectric tracking and measuring devices to calculate the intersection angle between two adjacent photoelectric tracking and measuring devices.

[0022] Furthermore, the calculation formula of the intersection angle in step S3 is:

[0023]

[0024] Where: θ is the intersection angle, and The target angular trajectory calculated by two adjacent optoelectronic tracking and measurement devices respectively.

[0025] Furthermore, in step S4, the method of performing Lagrangian interpolation on the target angle trajectory is as follows:

[0026] The angular trajectories at adjacent times t1, t2, and t3 are collected, which are (l1, m1, n1), (l2, m2, n2), and (l3, m3, n3) respectively. The target angular trajectory at time t is obtained by Lagrange interpolation using the angular trajectories of t1, t2, and t3 (l, m, n).

[0027]

[0028] Where: l1, l2, l3 are the first components of the angular trajectory at t1, t2, t3 respectively; m1, m2, m3 are the second components of the angular trajectory at t1, t2, t3 respectively; n1, n2, n3 are the third components of the angular trajectory at t1, t2, t3 respectively.

[0029] Compared with the prior art, the present invention has the following beneficial effects:

[0030] The present invention provides a four-station intersection measurement system, which increases the original two-station configuration to a four-station configuration. The four photoelectric tracking and measuring devices are arranged in a square distribution, and the baseline distance A between the first photoelectric tracking and measuring device and the fourth photoelectric tracking and measuring device is set according to the preset target observation distance X, so that A= X; At the same observation moment, four photoelectric tracking and measuring devices coordinate to observe the target, and the first photoelectric tracking and measuring device calculates the intersection angle between two adjacent photoelectric tracking and measuring devices to obtain four sets of intersection angles. According to the principle of intersection angle optimization, the data of the group of photoelectric tracking and measuring devices with the best positioning accuracy is selected for intersection positioning, thereby improving the target positioning accuracy and the coverage of measurable working conditions. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1 Schematic diagram of the geometric configuration of the measuring station and the target in a two-station configuration;

[0032] Figure 2 is the relationship curve between intersection angle and positioning error;

[0033] Figure 3 A schematic diagram of an embodiment of an intersection measurement system based on a four-station configuration according to the present invention;

[0034] Figure 4 Schematic diagram of the position distribution of the target and four photoelectric tracking and measuring devices in an embodiment of the intersection measurement method based on a four-station configuration of the present invention Figure 1 ;

[0035] Figure 5 Schematic diagram of the position distribution of the target and four photoelectric tracking and measuring devices in an embodiment of the intersection measurement method based on a four-station configuration of the present invention Figure 2 ;

[0036] Figure 6 Schematic diagram of the position distribution of the target and four photoelectric tracking and measuring devices in an embodiment of the intersection measurement method based on a four-station configuration of the present invention Figure 3 .

[0037] The following are the descriptions of the reference numerals:

[0038] 1-first photoelectric tracking and measuring device, 2-second photoelectric tracking and measuring device, 3-third photoelectric tracking and measuring device, 4-fourth photoelectric tracking and measuring device. DETAILED DESCRIPTION

[0039] The present invention will be further described below with reference to the accompanying drawings and exemplary embodiments.

[0040] Reference Figure 1 The intersection measurement system based on the four-station configuration of the present invention includes four photoelectric tracking and measuring devices distributed in a square, namely the first photoelectric tracking and measuring device 1, the second photoelectric tracking and measuring device 2, the third photoelectric tracking and measuring device 3 and the fourth photoelectric tracking and measuring device 4. The distance between two adjacent photoelectric tracking and measuring devices is the baseline distance A, then A= X, where X is the preset target observation distance.

[0041] The first optoelectronic tracking and measurement device 1 includes a tracking and image processing module and a positioning module. The tracking and image processing module and the positioning module are electrically connected. The tracking and image processing module is used for target tracking, coordinate extraction and angular trajectory calculation. The positioning module is used for real-time calculation of the three-dimensional trajectory and speed of the target. The tracking and image processing module is based on FPGA and eight-core DSP, while the positioning module is based on eight-core DSP.

[0042] In this embodiment, the final intersection angle calculation is performed in the positioning module of the first photoelectric tracking and measuring device 1, so the second photoelectric tracking and measuring device 2, the third photoelectric tracking and measuring device 3 and the fourth photoelectric tracking and measuring device 4 include tracking and image processing modules. The positioning module of the first photoelectric tracking and measuring device 1 is electrically connected to the tracking and image processing modules of the second photoelectric tracking and measuring device 2, the third photoelectric tracking and measuring device 3 and the fourth photoelectric tracking and measuring device 4, respectively. The target angle trajectory and respective station coordinates obtained by processing by the tracking and image processing modules of the second photoelectric tracking and measuring device 2, the third photoelectric tracking and measuring device 3 and the fourth photoelectric tracking and measuring device 4 can be remotely transmitted to the positioning module of the first photoelectric tracking and measuring device 1 for the next step of calculation.

[0043] At the same time, the present invention provides a four-station intersection measurement method, which uses the above-mentioned four-station intersection measurement system, including the following steps:

[0044] S1, the first photoelectric tracking and measuring device 1 to the fourth photoelectric tracking and measuring device 4 are arranged in a square distribution, and the baseline distance A between the first photoelectric tracking and measuring device 1 to the fourth photoelectric tracking and measuring device 4 is set according to the preset target observation distance X, so that

[0045] S2, the tracking and image processing modules of the first to fourth photoelectric tracking and measuring devices 1 to 4 extract the coordinates of the target in the image in real time and calculate the target angular trajectory, and the second to fourth photoelectric tracking and measuring devices 2 to 4 send their respective station coordinates and the calculated target angular trajectory to the positioning module of the first photoelectric tracking and measuring device 1;

[0046] S3. The positioning module of the first photoelectric tracking and measuring device 1 calculates the intersection angle between two adjacent photoelectric tracking and measuring devices using the target angle trajectory calculated by the tracking and image processing modules of the four photoelectric tracking and measuring devices;

[0047] The calculation formula for the intersection angle is:

[0048]

[0049] Where: θ is the intersection angle, and The target angular trajectory calculated by two adjacent optoelectronic tracking and measurement devices respectively;

[0050] S4. Selecting a pair of optoelectronic tracking and measuring devices with an optimal intersection angle, wherein the imaging time of the optoelectronic tracking and measuring devices includes a fixed deviation, maintaining the angular trajectory of one optoelectronic tracking and measuring device unchanged, and performing Lagrangian interpolation processing on the target angular trajectory of the other optoelectronic tracking and measuring device based on the imaging time of the optoelectronic tracking and measuring device with the unchanged angular trajectory;

[0051] The method for Lagrange interpolation of target angular trajectory is as follows:

[0052] The angular trajectories at adjacent times t1, t2, and t3 are collected, which are (l1, m1, n1), (l2, m2, n2), and (l3, m3, n3) respectively. The target angular trajectory (l, m, n) at time y is obtained by Lagrange interpolation using the angular trajectories of t1, t2, and t3.

[0053]

[0054] Where: l1, l2, l3 are the first components of the angular trajectory at t1, t2, t3 respectively; m1, m2, m3 are the second components of the angular trajectory at t1, t2, t3 respectively; n1, n2, n3 are the third components of the angular trajectory at t1, t2, t3 respectively;

[0055] S5. Using the target angular trajectory obtained after Lagrange interpolation and the site coordinates of the two optoelectronic tracking and measurement devices, the three-dimensional trajectory and velocity of the target are obtained through intersection calculation;

[0056] S6. Repeat steps S2 to S5 to complete the target intersection measurement based on the four-station configuration within the specified time period.

[0057] In order to verify the positioning accuracy of the intersection measurement system in this embodiment, the position distributions of three targets and four optoelectronic tracking and measurement devices are specially selected for verification.

[0058] First, as Figure 4 As shown, the target is located in the upper right corner of the square formed by four photoelectric tracking and measuring devices, the preset angular trajectory accuracy is 50 μrad, and the baseline length of the two adjacent stations is 700 km; at this time, the actual observation distances of the first photoelectric tracking and measuring device 1 to the fourth photoelectric tracking and measuring device 4 are 1027.034 km, 341.760 km, 880.227 km and 1308.739 km respectively.

[0059] After calculation, the intersection angle of the first photoelectric tracking and measuring device 1 and the second photoelectric tracking and measuring device 2 is 13.8462°, and the intersection positioning error is 228.75m; the intersection angle of the second photoelectric tracking and measuring device 2 and the third photoelectric tracking and measuring device 3 is 48.1260°, and the intersection positioning error is 67.41m; the intersection angle of the third photoelectric tracking and measuring device 3 and the fourth photoelectric tracking and measuring device 4 is 29.8855°, and the intersection positioning error is 164.68m; the intersection angle of the first photoelectric tracking and measuring device 1 and the fourth photoelectric tracking and measuring device 4 is 32.0867°, and the intersection positioning error is 163.69m. Figure 1 From the relationship between the intersection angle and the positioning error shown, it can be seen that the closer the intersection angle is to 90°, the smaller the positioning error and the higher the accuracy. Therefore, the intersection angle between the second photoelectric tracking and measuring device 2 and the third photoelectric tracking and measuring device 3 is optimal, and its intersection positioning error is the smallest. According to the principle of optimal intersection angle, the intersection positioning result of the second photoelectric tracking and measuring device 2 and the third photoelectric tracking and measuring device 3 should be used as the final target positioning result.

[0060] Secondly, Figure 5 As shown, the target is located in the upper left corner of the square formed by four photoelectric tracking and measuring devices, the preset angular trajectory accuracy is 50 μrad, and the baseline length between two adjacent stations is 700 km; at this time, the actual observation distances of the first photoelectric tracking and measuring device 1 to the fourth photoelectric tracking and measuring device 4 are 320.624 km, 1020.196 km, 1248.519 km and 787.909 km respectively.

[0061] Calculations show that the intersection angle between the first and second photoelectric tracking and measuring devices 1 and 2 is 2.4530°, with an intersection positioning error of 1267.72m. The intersection angle between the second and third photoelectric tracking and measuring devices 2 and 3 is 34.0943°, with an intersection positioning error of 148.91m. The intersection angle between the third and fourth photoelectric tracking and measuring devices 3 and 4 is 30.8199°, with an intersection positioning error of 146.93m. The intersection angle between the first and fourth photoelectric tracking and measuring devices 1 and 4 is 62.4612°, with an intersection positioning error of 51.75m. The intersection angle between the first and fourth photoelectric tracking and measuring devices 1 and 4 is optimal, with the smallest intersection positioning error. Based on the principle of optimal intersection angle selection, the intersection positioning result of the first and fourth photoelectric tracking and measuring devices 1 and 4 should be used as the final target positioning result.

[0062] Finally, Figure 6 As shown, the target is located inside the square formed by the four photoelectric tracking and measuring devices and close to the upper left, the preset angular trajectory accuracy is 50 μrad, and the baseline length between the two adjacent stations is 700 km; at this time, the actual observation distances of the first photoelectric tracking and measuring device 1 to the fourth photoelectric tracking and measuring device 4 are 196.977 km, 526.118 km, 809.197 km and 645.600 km respectively.

[0063] Calculations show that the intersection angle between the first and second photoelectric tracking and measurement devices 1 and 2 is 147.2913°, with an intersection positioning error of 53.97m. The intersection angle between the second and third photoelectric tracking and measurement devices 2 and 3 is 58.7593°, with an intersection positioning error of 61.51m. The intersection angle between the third and fourth photoelectric tracking and measurement devices 3 and 4 is 56.1761°, with an intersection positioning error of 67.51m. The intersection angle between the first and fourth photoelectric tracking and measurement devices 1 and 4 is 97.7733°, with an intersection positioning error of 37.87m. The intersection angle between the first and fourth photoelectric tracking and measurement devices 1 and 4 is optimal, with the smallest intersection positioning error. Based on the principle of optimal intersection angle selection, the intersection positioning result of the first and fourth photoelectric tracking and measurement devices 1 and 4 should be used as the final target positioning result.

[0064] In summary, when the four-station intersection measurement system in this embodiment locates the target, there is a station combination with the optimal intersection angle, and its positioning error is small. Compared with the traditional two-station intersection measurement system, the four-station intersection measurement system improves the target positioning accuracy. In application scenarios with positioning accuracy requirements, the four-station intersection measurement system greatly improves the target measurable working condition coverage.

[0065] The embodiments described above are merely descriptions of specific implementation methods of the present invention and are not intended to limit the scope of the present invention. Without departing from the design spirit of the present invention, various modifications and improvements made to the technical solutions of the present invention by ordinary technicians in this field should fall within the scope of protection determined by the claims of the present invention.

Claims

1. An intersection measurement system based on a four-station configuration, characterized in that: The invention comprises four photoelectric tracking and measuring devices, namely a first photoelectric tracking and measuring device (1) to a fourth photoelectric tracking and measuring device (4); The first photoelectric tracking and measuring device (1) to the fourth photoelectric tracking and measuring device (4) are distributed in a square shape, and the first photoelectric tracking and measuring device (1) is electrically connected to the second photoelectric tracking and measuring device (2), the third photoelectric tracking and measuring device (3) and the fourth photoelectric tracking and measuring device (4) respectively; Define the distance between two adjacent photoelectric tracking and measuring devices as the baseline distance A, then Where: X is the preset target observation distance.

2. The intersection measurement system based on the four-station configuration according to claim 1, characterized in that: The first photoelectric tracking and measuring device (1) comprises a tracking and image processing module and a positioning module; the second photoelectric tracking and measuring device (2), the third photoelectric tracking and measuring device (3) and the fourth photoelectric tracking and measuring device (4) comprise a tracking and image processing module; The tracking and image processing module is electrically connected to the positioning module, the tracking and image processing module is used for target tracking, coordinate extraction and angular trajectory calculation, and the positioning module is used for real-time calculation of the three-dimensional trajectory and speed of the target; The positioning module of the first photoelectric tracking and measuring device (1) is electrically connected to the tracking and image processing modules of the second photoelectric tracking and measuring device (2), the third photoelectric tracking and measuring device (3) and the fourth photoelectric tracking and measuring device (4), respectively.

3. A four-station configuration-based intersection measurement method, using the four-station configuration-based intersection measurement system according to any one of claims 1-2, characterized in that: The following steps are involved: S1. Arrange the first photoelectric tracking and measuring device (1) to the fourth photoelectric tracking and measuring device (4) in a square distribution, and set the baseline distance A between the first photoelectric tracking and measuring device (1) to the fourth photoelectric tracking and measuring device (4) according to the preset target observation distance X, so that S2, the first photoelectric tracking and measuring device (1) to the fourth photoelectric tracking and measuring device (4) extract the coordinates of the target in the image in real time and calculate the target angle trajectory, and the second photoelectric tracking and measuring device (2) to the fourth photoelectric tracking and measuring device (4) send their respective station coordinates and the calculated target angle trajectory to the first photoelectric tracking and measuring device (1); S3, the first photoelectric tracking and measuring device (1) calculates the intersection angle between two adjacent photoelectric tracking and measuring devices using the target angle trajectory measured by the four photoelectric tracking and measuring devices; S4, selecting a pair of optoelectronic tracking and measuring devices with an optimal intersection angle, wherein the imaging time of the optoelectronic tracking and measuring devices includes a fixed deviation, and at this time, keeping the angular trajectory of one of the optoelectronic tracking and measuring devices unchanged, and the other optoelectronic tracking and measuring device performs Lagrangian interpolation processing on the target angular trajectory based on the imaging time of the optoelectronic tracking and measuring device with the unchanged angular trajectory; S5, using the target angular trajectory obtained after Lagrange interpolation and the site coordinates of the two optoelectronic tracking and measuring devices, the three-dimensional trajectory and speed of the target are obtained through intersection calculation; S6. Repeat steps S2 to S5 to complete the target intersection measurement based on the four-station configuration within a specified time period.

4. The intersection measurement method based on four-station configuration according to claim 3 is characterized in that: Step S2 specifically comprises: the tracking and image processing modules of the first photoelectric tracking and measuring device (1) to the fourth photoelectric tracking and measuring device (4) extract the coordinates of the target in the image in real time and calculate the target angular trajectory, and the second photoelectric tracking and measuring device (2) to the fourth photoelectric tracking and measuring device (4) send their respective station coordinates and the calculated target angular trajectory to the positioning module of the first photoelectric tracking and measuring device (1).

5. The intersection measurement method based on four-station configuration according to claim 4 is characterized in that: Step S3 specifically comprises: the positioning module of the first photoelectric tracking and measuring device (1) calculates the intersection angle between two adjacent photoelectric tracking and measuring devices using the target angle trajectory calculated by the tracking and image processing modules of the four photoelectric tracking and measuring devices.

6. The intersection measurement method based on four-station configuration according to claim 5, characterized in that: The calculation formula of the intersection angle in step S3 is: Where: θ is the intersection angle, and The target angle trajectories calculated by two adjacent optoelectronic tracking and measuring devices respectively.

7. The intersection measurement method based on four-station configuration according to claim 6 is characterized in that: In step S4, the method of performing Lagrangian interpolation on the target angle trajectory is as follows: The angular trajectories at adjacent times t1, t2, and t3 are collected, which are (l1, m1, n1), (l2, m2, n2), and (l3, m3, n3) respectively. The target angular trajectory (l, m, n) at time t is obtained by Lagrange interpolation calculation using the angular trajectories of t1, t2, and t3. Wherein: l1, l2, l3 are the first components of the angular trajectory at t1, t2, t3 respectively; m1, m2, m3 are the second components of the angular trajectory at t1, t2, t3 respectively; n1, n2, n3 are the third components of the angular trajectory at t1, t2, t3 respectively.

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