An automatic attitude monitoring and adjusting device for SAR calibrator

Abstract

The present invention provides an automatic attitude monitoring and adjusting device for an SAR calibrator, which relates to the technical field of remote sensing positioning. The device includes: an SAR calibrator network, a three-axis sensor module, a Beidou positioning module, a 4G data transmission module, a programmable board, a remote control computer, and a power supply system. By designing multiple triangular calibrators as an SAR calibrator network and installing a three-axis sensor module and a Beidou positioning module, the attitude and positioning of multiple triangular calibrators are automatically monitored simultaneously. On this basis, by designing a 4G data transmission module, a programmable board, and a remote control computer to be remotely communicatively connected to the three-axis sensor module and the Beidou positioning module, the automatic acquisition and processing of attitude and positioning data are completed, and further the automatic attitude adjustment of multiple triangular calibrators is realized, improving the installation accuracy of the calibrator without manual participation.

Description

Technical Field

[0001] The present invention relates to the technical field of remote sensing positioning, and particularly to an automatic monitoring and adjusting device for the attitude of a SAR calibrator. Background Art

[0002] With the development of satellite and airborne microwave synthetic aperture radar (SAR) remote sensing technology, the calibration problem of SAR has become increasingly prominent. The quality of the calibration effect is directly related to the quantitative application of SAR data. Therefore, improving the layout accuracy and effect of ground calibrators is one of the key steps to improve the calibration accuracy of SAR data.

[0003] There are many installation and monitoring methods for existing SAR calibrators, but there is still a large gap from the application requirements. First, the attitude adjustment methods of existing calibrators are diverse and flexible, but mainly manual adjustment. Although the attitude of the calibrator can be checked by installing an attitude adjustment device, the degree of automation is low, and the attitude adjustment after checking is still mainly manual operation. Second, by designing a device based on mechanical adjustment such as a servo motor, the difficulty and workload of manual placement and adjustment can be greatly reduced, but the real-time network monitoring and automatic adjustment of the calibrator attitude have not been achieved. By introducing the GNSS system, although the real-time positioning of the calibrator can be achieved, the solution to the orientation and attitude determination problems of the calibrator is insufficient, and the orientation and attitude of the corner reflector are precisely the key factors directly affecting the calibration accuracy, thus limiting its application potential in SAR calibration. In addition, the existing technology does not fully utilize the mutual constraint relationship between points in the calibrator observation network, and the corner reflectors are not related to each other after installation. Summary of the Invention

[0004] The present invention provides an automatic monitoring and adjusting device for the attitude of a SAR calibrator, which can solve the problems of positioning, orientation and dynamic measurement of the three-dimensional attitude of the calibrator in the prior art, realize the automatic monitoring and adjustment of its attitude, improve the placement accuracy of the calibrator, and has a high degree of automation.

[0005] The present invention provides an automatic monitoring and adjusting device for the attitude of a SAR calibrator, comprising:

[0006] SAR calibrator networking, a three-axis sensor module, a Beidou positioning module, a 4G data transmission module, a programmable board, a remote control computer, and a power supply system;

[0007] Wherein, the SAR calibrator networking is composed of multiple triangular calibrators. A three-axis sensor included in the three-axis sensor module is fixedly installed on the bottom surface of the triangular pyramid of each triangular calibrator. A positioning base is installed below the triangular calibrator, and a servo motor is installed on the positioning base. The positioning base is fixedly connected to the bottom surface of the triangular pyramid of the triangular calibrator through a connecting rod;

[0008] The Beidou positioning module is installed in one or more triangular calibrators in the SAR calibrator network;

[0009] The programmable board is installed on the remote control computer, and the programmable board is remotely communicatively connected to the triaxial sensor module, the Beidou positioning module, the 4G data transmission module, and the controller installed on the triangular calibrator;

[0010] The power supply system is electrically connected to the Beidou positioning module, the triaxial sensor module, and the 4G data transmission module respectively.

[0011] In some embodiments, the Beidou positioning device included in the Beidou positioning module is installed at the apex of the triangular pyramid of the triangular calibrator. A spirit level is also installed on the bottom surface of the triangular pyramid of the triangular calibrator. A buckle structure is installed on the side surface of the triangular pyramid of the triangular calibrator. The buckle structure is used to connect the controller, and the controller is communicatively connected to the servo motor.

[0012] Furthermore, the positioning base installed below the triangular calibrator includes a rotating disk. The rotating disk is used to rotate the triangular calibrator in the horizontal direction. Three horizontal adjustment knobs are installed on the back of the rotating disk. The horizontal adjustment knobs are used to fix the rotating disk in a horizontal state.

[0013] Furthermore, the positioning base installed below the triangular calibrator includes a circular rail and three slide rail vehicles;

[0014] The bottom surface of the triangular pyramid of the triangular calibrator is fixedly connected to the three slide rail vehicles respectively through three connecting rods. The three slide rail vehicles are installed on the circular rail.

[0015] Furthermore, the positioning base installed below the triangular calibrator further includes a connecting rod sleeve. Each connecting rod adopts a three-section structure, and each section of the connecting rod is threadedly connected through the connecting rod sleeve.

[0016] Furthermore, the servo motor installed on the positioning base includes a rolling servo motor and three attitude control servo motors. The rolling servo motor is installed on any one of the slide rail vehicles, and the three attitude control servo motors are respectively installed on the three connecting rods.

[0017] In some embodiments, in the SAR calibrator network, the triaxial sensors installed on each triangular calibrator are used to collect the attitude measurement signals of the triangular calibrator;

[0018] The Beidou positioning module is used to collect the positioning signals of each triangular calibrator;

[0019] The programmable board is used to send the attitude measurement signal and the positioning signal to a remote control computer through the 4G data transmission module for attitude calculation;

[0020] The remote control computer is used to send a control instruction signal according to the result of the attitude calculation;

[0021] The programmable board is also used to receive the control instruction signal through the 4G data transmission module and send the control instruction signal to the controller in each triangulation calibrator. The control instruction signal is used to drive the servo motor installed in the positioning base of the triangulation calibrator to adjust the attitude of the triangulation calibrator.

[0022] Further, the attitude calculation process of the remote control computer includes:

[0023] Performing measurement adjustment calculation on the coordinate parameters included in the positioning signal of each triangulation calibrator and the extension line of the azimuth angle of the bottom surface of the triangular pyramid of the triangulation calibrator to obtain adjusted coordinates;

[0024] Determining the azimuth baseline data of the triangulation calibrator according to the adjusted coordinates;

[0025] Calculating the azimuth adjustment amount according to the actual azimuth angle included in the attitude measurement signal of each triangulation calibrator and the azimuth baseline data;

[0026] Converting the azimuth adjustment amount into the step amount of the servo motor as the result of the attitude calculation.

[0027] Further, the remote control computer is also used to compare the azimuth adjustment amount with a preset limit difference after calculating the azimuth adjustment amount;

[0028] When the azimuth adjustment amount is greater than the preset limit difference, a warning signal is sent.

[0029] In some embodiments, the process of the servo motor adjusting the attitude of the triangulation calibrator includes:

[0030] Adjusting the link rod according to the step amount of the servo motor included in the control instruction signal to adjust the rotation angle parameters of the triangulation calibrator. The rotation angle parameters include the heading angle, pitch angle, and roll angle in the three-axis directions.

[0031] The SAR calibrator attitude automatic monitoring and adjustment device provided by the present invention designs multiple triangular calibrators as a SAR calibrator network, and installs a three-axis sensor module and a Beidou positioning module to automatically monitor the attitudes and positions of the multiple triangular calibrators simultaneously. On this basis, by designing a 4G data transmission module, a programmable board, a remote control computer to conduct remote communication connections with the three-axis sensor module and the Beidou positioning module, the automatic acquisition and processing of attitude and position data are completed, and then the automatic adjustment of the attitudes of the multiple triangular calibrators is realized, improving the installation accuracy of the calibrators without manual participation. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] In order to more clearly illustrate the technical solutions in the present invention or the prior art, the accompanying drawings required for use in the description of the embodiments or the prior art will be briefly introduced one by one below. Obviously, the accompanying drawings in the following description are some embodiments of the present invention. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0033] Figure 1 It is a schematic diagram of the overall structure of the SAR calibrator attitude automatic monitoring and adjustment device provided by the present invention.

[0034] Figure 2 It is an application schematic diagram of the triangular calibrator provided by the present invention.

[0035] Figure 3 It is an example structure diagram of the SAR calibrator network provided by the present invention.

[0036] Figure 4 It is one of the schematic diagrams of the structure of the triangular calibrator provided by the present invention.

[0037] Figure 5 It is another schematic diagram of the structure of the triangular calibrator provided by the present invention.

[0038] Figure 6 It is a third schematic diagram of the structure of the triangular calibrator provided by the present invention.

[0039] Figure 7 It is one of the schematic diagrams of the structure of the positioning base of the triangular calibrator provided by the present invention.

[0040] Figure 8 It is another schematic diagram of the structure of the positioning base of the triangular calibrator provided by the present invention.

[0041] Figure 9 It is a schematic diagram of the rotation angle parameter of the bottom surface of the triangular pyramid of the triangular calibrator provided by the present invention.

[0042] Reference numerals:

[0043] 1. Triangular calibrator; 2. Beidou positioning device; 3. Level bubble; 4. Triaxial sensor; 5. Controller; 501. First link rod; 502. Second link rod; 503. Third link rod; 5031. Calibrator section; 5032. Intermediate section; 5033. Base section; 6. Rotating disk; 7. Circular rail; 801. First slide rail vehicle; 802. Second slide rail vehicle; 803. Third slide rail vehicle; 800. First connecting rod sleeve; 810. Second connecting rod sleeve; 900. Rolling servo motor; 901. First attitude control servo motor; 902. Second attitude control servo motor; 903. Third attitude control servo motor. Detailed implementation manners

[0044] To make the objectives, technical solutions and advantages of the present invention clearer, the technical solutions in the present invention will be clearly and completely described below with reference to the accompanying drawings in the present invention. Obviously, the described embodiments are some but not all of the embodiments of the present invention. All other embodiments obtained by those of ordinary skill in the art based on the embodiments in the present invention without making creative efforts shall fall within the protection scope of the present invention.

[0045] The SAR calibrator attitude automatic monitoring and adjusting device of the present invention is described below with reference to the accompanying drawings. Figure 1 is the overall structural schematic diagram of the SAR calibrator attitude automatic monitoring and adjusting device provided by the present invention. As Figure 1 shown, the SAR calibrator attitude automatic monitoring and adjusting device specifically includes: SAR calibrator network, triaxial sensor module, Beidou positioning module, 4G data transmission module, programmable board, remote control computer, and power system.

[0046] Among them, the SAR calibrator network is composed of multiple triangular calibrators. The triangular calibrator is in the shape of a triangular pyramid. For specific reference, see Figure 2 . When using a triangular calibrator (usually a regular tetrahedron, that is, a triangular pyramid) for SAR calibration, it is necessary to adjust the orientation and attitude of the bottom surface (a triangular surface) of the triangular pyramid so that the outer edges of the bottom surface of the triangular pyramid (that is, the outer edges of the triangular surface) are parallel to the corresponding flight route. Generally, the opening surface of the triangular calibrator is a certain side surface of the triangular pyramid, and it is ensured that the line connecting the center of the opening surface and the vertex of the corresponding triangular pyramid is perpendicular to the corresponding flight route (SAR side-looking flight) in space.

[0047] Meanwhile, in order to overcome the defect that the prior art fails to fully utilize the mutual constraint relationship among points in the calibrator observation network to achieve high-precision automatic positioning and orientation of the calibrator, in the embodiment of the present invention, a plurality of triangular calibrators are constructed into a SAR calibrator network. Each triangular calibrator is used as a vertex. By connecting the vertices and according to the direction of the connection lines, the azimuth direction of the bottom surface of the triangular pyramid of the triangular calibrator can be calculated using the positioning coordinates of the vertices to determine the baseline data of the triangular calibrator. After connecting the triangular calibrators as vertices, a SAR calibrator network can be formed. For example, Figure 3 as shown Figure 3 in the figure shows a SAR calibrator network constructed by eight triangular calibrators A, B, C, D, E, F, G, and H.

[0048] A three-axis sensor module including a three-axis sensor is fixedly installed on the bottom surface of the triangular pyramid of each triangular calibrator. The three-axis sensor is used to measure the attitude angle of the triangular calibrator, specifically to measure the rotation angles of the bottom edge of the triangular pyramid bottom surface in the Y, X, and Z axis directions in a three-dimensional rectangular coordinate system.

[0049] A positioning base is installed below the triangular calibrator to support the triangular positioner. A servo motor is installed on the positioning base. The positioning base is fixedly connected to the bottom surface of the triangular pyramid of the triangular calibrator through a connecting rod. The servo motor can adjust the connecting rod, and thus adjust the attitude of the triangular calibrator.

[0050] The Beidou positioning module is installed in one or more triangular calibrators in the SAR calibrator network. The Beidou positioning module includes at least one Beidou positioning device. That is to say, in the SAR calibrator network, a Beidou positioning device can be installed on only one triangular calibrator, or on some triangular calibrators, or on all triangular calibrators. It depends on the specific situation and is not limited in the embodiment of the present invention. The Beidou positioning device can simultaneously collect satellite positioning signals such as Beidou, GPS, and Glonass.

[0051] The programmable board is installed on the remote control computer. The programmable board is remotely communicatively connected to the triaxial sensor module, the Beidou positioning module, the 4G data transmission module, and the controller installed on the triangular calibrator, namely, remote wireless network communication. In this way, the positioning signals and attitude measurement signals collected by the triaxial sensor module and the Beidou positioning module can be automatically transmitted to the programmable board of the remote control computer through the 4G data transmission module for attitude calculation, so that the remote control computer can send control instruction signals. The controller installed on the triangular calibrator is used to receive the control instruction signals sent by the remote control computer to drive the servo motor on the positioning base to adjust the link rod, and then adjust the attitude of the triangular calibrator. In this way, the automatic monitoring of the attitude and positioning of the triangular calibrator can be carried out simultaneously, and the automatic acquisition and processing of attitude and positioning data can be completed, realizing the automatic adjustment of the attitude of the triangular calibrator.

[0052] In addition, the SAR calibrator attitude automatic monitoring and adjustment device also designs a power supply system, and the power supply system is electrically connected to the Beidou positioning module, the triaxial sensor module, and the 4G data transmission module respectively.

[0053] The power supply system can be a storage battery or a solar panel, which can supply power to the Beidou positioning module, the triaxial sensor module, and the 4G data transmission module to ensure the normal operation of each module.

[0054] In the embodiment of the present invention, by designing multiple triangular calibrators as an SAR calibrator network and installing a triaxial sensor module and a Beidou positioning module, the automatic monitoring of the attitude and positioning of multiple triangular calibrators is carried out simultaneously. On this basis, by designing the 4G data transmission module, the programmable board, the remote control computer to be remotely communicatively connected to the triaxial sensor module and the Beidou positioning module, the automatic acquisition and processing of attitude and positioning data are completed, and then the automatic adjustment of the attitude of multiple triangular calibrators is realized, improving the installation accuracy of the calibrator without manual participation.

[0055] Furthermore, as Figure 4 shown, for each triangular calibrator in the SAR calibrator network, the Beidou positioning device 2 included in the Beidou positioning module is installed at the apex of the triangular pyramid of the triangular calibrator 1 and serves as the apex antenna of the triangular calibrator 1. It can be a Global Positioning System (GPS) device, which can simultaneously collect satellite positioning signals such as Beidou, GPS, and Glonass to position the triangular calibrator 1.

[0056] A spirit level bubble 3 is also installed on the bottom surface of the triangular pyramid of the triangular calibrator 1. According to the spirit level bubble 3, it can be clearly determined whether the bottom surface of the triangular pyramid of the triangular calibrator 1 is in a horizontal state or parallel to the horizontal ground. The three-axis sensor module includes a three-axis sensor 4 which is installed on the bottom surface of the triangular pyramid of the triangular calibrator 1 to measure the rotation angles of the bottom edge of the bottom surface of the triangular pyramid in the three directions of the Y, X, and Z axes in a three-dimensional rectangular coordinate system.

[0057] When the triangular calibrator 1 is initially installed, the Y-axis direction of the three-axis sensor 4 is perpendicular to the outer edge of the bottom surface of the triangular pyramid. The Y-axis is parallel to the perpendicular line of the bottom surface. The X-axis is also on the bottom surface of the triangular pyramid and perpendicular to the Y-axis. The Z-axis is perpendicular to the X-axis and Y-axis of the bottom surface of the triangular pyramid. The three-axis sensor 4 can measure the relative coordinates of the center position of the three-axis sensor 4 and the Beidou positioning device 2 in the three-axis sensor Y-X coordinate system, which is one of the starting data for the subsequent spatial position relationship. During the initial installation, by adjusting the positioning base, the spirit level bubble 3 is centered to ensure that the bottom surface of the triangular pyramid of the triangular calibrator 1 is in a horizontal state or parallel to the horizontal ground.

[0058] As Figure 5 shown, a buckle structure is installed on the side surface of the triangular pyramid of the triangular calibrator 1. The buckle structure is used to connect the controller 5. The controller 5 is communicatively connected to the servo motor, such as wireless network communication, to convey control instruction signals to the servo motor of the positioning base to realize the automatic adjustment of the attitude of the triangular calibrator.

[0059] In the embodiment of the present invention, a three-axis sensor module and a Beidou positioning module are installed in each triangular calibrator in the SAR calibrator network. By combining the SAR calibrator network and the three-axis sensor, on one hand, the characteristics of mutual verification among the vertices in the SAR calibrator network are utilized, and the advantage of the stable spatial structure of each vertex in the control network is exerted to improve the positioning accuracy. On the other hand, the three-axis sensor is used to measure the attitude of the triangular calibrator at each vertex, thereby realizing the automatic monitoring of the attitude and positioning of multiple triangular calibrators simultaneously.

[0060] To achieve precise positioning and attitude measurement of the triangular calibrator, it is necessary to ensure a certain stability during the installation of the triangular calibrator. Therefore, how to design the positioning base is particularly crucial. The positioning base plays a role in fixing the triangular calibrator, bearing the main body of the triangular calibrator and other components, and at the same time has the function of leveling the bottom surface of the triangular calibrator (ensuring that the bottom surface of the triangular calibrator is in a horizontal state in the initial state). In the embodiment of the present invention, there are two connection methods between the triangular calibrator and the positioning base. The first is as Figure 5 shown. The link rod is installed on the side surface of the triangular pyramid of the calibrator. Since there are three side surfaces of the triangular pyramid of the triangular calibrator, three link rods (including the first link rod 501, the second link rod 502, and the third link rod 503) need to be designed. The second is as Figure 6As shown, the Beidou positioning device 2 is installed at the apex of the triangular pyramid of the triangular calibrator, and the connecting rods (including the first connecting rod 501, the second connecting rod 502, and the third connecting rod 503) are connected to the connecting ridges (i.e., the side edges of the triangular pyramid) of the triangular pyramid of the triangular calibrator. Generally, when the inclination angle of the attitude adjustment of the triangular calibrator is relatively large, the second method is easier to implement.

[0061] Regarding the design of the positioning base, in some embodiments, such as Figure 7 As shown, the positioning base installed below the triangular calibrator includes a rotating disk 6, that is, the rotating disk 6 is fixedly connected to the triangular calibrator through the first connecting rod 501, the second connecting rod 502, and the third connecting rod 503. The rotating disk 6 is used to rotate the triangular calibrator in the horizontal direction. Three horizontal adjustment knobs are arranged on the back of the rotating disk, and the horizontal adjustment knobs are used to fix the rotating disk in a horizontal state. When the triangular calibrator is initially placed, the bottom surface of the triangular pyramid of the triangular calibrator is kept parallel to the rotating disk 6, so as to ensure that the bottom surface of the triangular pyramid is in a horizontal state. When the attitude of the triangular calibrator needs to be adjusted, the connecting rod can be lifted and lowered by the servo motor installed on the rotating disk 6. The connecting rod adopts a telescopic structure, and the length of the connecting rod is controlled by telescoping, so as to adjust the attitude of the triangular calibrator.

[0062] In the embodiment of the present invention, by designing the positioning base of the triangular calibrator into the structure of a rotating disk, it is possible to strictly ensure that the rotating disk is in a horizontal state by freely adjusting the horizontal adjustment knobs, and further ensure that the bottom surface of the triangular pyramid of the triangular calibrator is also in a horizontal state, making it stable and ensuring the accuracy of attitude measurement.

[0063] In some embodiments, in order to facilitate the subsequent automatic adjustment of the attitude of the triangular calibrator, the positioning base of the triangular calibrator can also be designed into the structure of a circular track, such as Figure 8 As shown, the positioning base installed below the triangular calibrator includes a circular track 7 and three slide rail vehicles, specifically including the first slide rail vehicle 801, the second slide rail vehicle 802, and the third slide rail vehicle 803. The bottom surface of the triangular pyramid of the triangular calibrator is fixedly connected to the three slide rail vehicles through three connecting rods (including the first connecting rod 501, the second connecting rod 502, and the third connecting rod 503). The three slide rail vehicles are installed on the circular track 7, and the installation angles between the connecting rods on the three slide rail vehicles are all 120 degrees.

[0064] In this way, by sliding the slide rail vehicle on the circular track, it is convenient to automatically adjust the attitude of the triangular calibrator. The slide rail has a small contact area with the ground, good directionality and stability. Under the same conditions, compared with the traditional square base, it is lighter in weight and has stronger wind resistance and anti-disturbance ability. In addition, the slide rail can be folded in a four-way manner, reducing the transportation and storage volume.

[0065] Furthermore, as Figure 8As shown, the positioning base installed below the triangular calibrator further includes a connecting rod sleeve. Each connecting rod adopts a three-section structure, and each section of the connecting rod is connected by a threaded connection of the connecting rod sleeve (including the first connecting rod sleeve 800 and the second connecting rod sleeve 810). Taking Figure 8 the third connecting rod 503 in it as an example, the third connecting rod 503 adopts a three-section structure, including a calibrator section 5031 connected to the triangular calibrator, an intermediate section 5032, and a base section 5033 connected to the third slide rail vehicle 803 of the positioning base. The calibrator section 5031 and the intermediate section 5032 are connected by a threaded connection of the first connecting rod sleeve 800, and the intermediate section 5032 is connected to the base section 5033 by a threaded connection of the second connecting rod sleeve 810. The threads in the connecting rod sleeve are all provided with hollow allowances, and this hollow allowance determines the lifting height of the connecting rod connected thereto, as well as the attitude adjustment allowance of the triangular calibrator at this position.

[0066] Through the above design of the connecting rod, the connecting rod can freely expand and contract in the direction perpendicular to the ground. And through the expansion and contraction of the connecting rod at different heights and the sliding of the slide rail vehicle, the attitude (azimuth angle) of the bottom surface of the triangular pyramid of the triangular coordinate device can be reasonably controlled.

[0067] Furthermore, as Figure 8 shown, the servo motors installed on the positioning base include a rolling servo motor 900 and three attitude control servo motors (including the first attitude control servo motor 901, the second attitude control servo motor 902, and the third attitude control servo motor 903). The rolling servo motor 900 is installed on any one of the slide rail vehicles. Figure 8 In the example in it, the rolling servo motor 900 is installed on the second slide rail vehicle 802. The rolling servo motor 900 provides the power for the movement of the three slide rail vehicles, thereby providing the rotational power for the triangular calibrator. And the three attitude control servo motors are respectively installed on the three connecting rods (including the first connecting rod 501, the second connecting rod 502, and the third connecting rod 503). Figure 8 In the example in it, the first attitude control servo motor 901 is installed on the first connecting rod 501, the second attitude control servo motor 902 is installed on the second connecting rod 502, and the third attitude control servo motor 903 is installed on the third connecting rod 503. The specific position can be installed on the base section of the connecting rod.

[0068] When the triangular calibrator is initially installed, by adjusting the connecting rod sleeves of the three connecting rods, the bottom surface of the triangular pyramid of the triangular calibrator is made to be in a horizontal state. By rotating the slide rail vehicle, the opening of the triangular calibrator faces north, and the direction of the perpendicular line of the bottom surface of the triangular pyramid points north, that is, the Y-axis direction of the three-axis sensor points north. When the controller of the triangular calibrator receives a control instruction signal and needs to drive the servo motor for attitude adjustment, the three connecting rods drive the corresponding connecting rods to rise and fall through the attitude control servo motor, realizing the attitude adjustment of the triangular calibrator in the Y-X-Z three-axis directions, and the adjustment amount is measured and monitored by the three-axis sensor.

[0069] Specifically, as Figure 8 shown, by rotating the thread of the first connecting rod sleeve 800, the lifting of the calibrator section 5031 of the third connecting rod 503 is realized. The second connecting rod sleeve 810 is threadedly connected to the base section 5033 of the third connecting rod 503 and the third attitude control servo motor 903. The third attitude control servo motor 903 can control the rotation of the thread of the second connecting rod sleeve 810, thereby realizing the lifting of the entire third connecting rod 503, and further changing the direction attitude of the bottom surface of the triangular pyramid of the triangular calibrator.

[0070] In the embodiment of the present invention, a rolling servo motor and an attitude control servo motor are designed in the positioning base part, which can automatically control the movement of the slide rail vehicle and the automatic lifting of the connecting rods. Combining with the base design in the form of a circular rail, on the premise of ensuring the accurate measurement of the direction attitude of the triangular calibrator, the automatic adjustment of the direction attitude can be realized without any manual operation.

[0071] In some embodiments, the accurate measurement and automatic adjustment of the direction attitude of the triangular calibrator mainly rely on the controller of the triangular calibrator receiving a control instruction signal, and the control instruction signal is received after the attitude calculation of the positioning signal and the attitude measurement signal collected by the three-axis sensor module and the Beidou positioning module. Specifically, in the SAR calibrator network, the three-axis sensors installed on each triangular calibrator are used to collect the attitude measurement signals of the triangular calibrator, specifically the actual azimuth angles of the bottom surface of the triangular pyramid of the triangular calibrator, that is, the rotation angles of the bottom surface of the triangular pyramid along the Y-X-Z three axes.

[0072] The Beidou positioning module is used to collect the positioning signals of each triangular calibrator. The Beidou positioning device installed on the top antenna of the triangular calibrator receives satellite positioning signals such as Beidou, GPS, and Glonass to position the triangular calibrator and obtain coordinate parameters.

[0073] The attitude calculation of the positioning signal and the attitude measurement signal is realized by a remote control computer, which is installed with a programmable board. After collecting the positioning signal and the attitude measurement signal from the three-axis sensor module and the Beidou positioning module, the programmable board sends the attitude measurement signal and the positioning signal to the remote control computer through the 4G data transmission module for attitude calculation.

[0074] The remote control computer is used to send control instruction signals according to the result of attitude calculation. The programmable board receives the control instruction signals through the 4G data transmission module and sends the control instruction signals to the controllers in each triangular calibrator. The control instruction signals are used to drive the servo motors installed in the positioning bases of the triangular calibrators to adjust the attitude of the triangular calibrators.

[0075] If the positioning base is designed as a Figure 7 rotating disk as shown, the servo motor on the rotating disk is directly driven, and the telescoping of the operating link is used to control the lifting to realize the attitude adjustment of the triangular calibrator.

[0076] If the positioning base is designed as a Figure 8 circular track as shown, the rolling servo motor is directly driven to rotate the slide car on the circular track, and at the same time, the attitude control servo motor is also driven to operate the threaded rotation of the connecting rod sleeve, thereby adjusting the lifting of the connecting rod to realize the attitude adjustment of the triangular calibrator.

[0077] In the embodiment of the present invention, by designing the 4G data transmission module, the programmable board, the remote control computer to be remotely communicatively connected with the three-axis sensor module and the Beidou positioning module, the automatic acquisition and processing of attitude and positioning data are completed. Furthermore, by using the attitude calculation and control instruction sending of the remote control computer, the automatic attitude adjustment of multiple triangular calibrators in the SAR calibrator network is realized, the installation accuracy of the calibrators is improved, and no manual participation is required.

[0078] The following introduces the attitude calculation process of the remote control computer. First, the measurement adjustment calculation is performed on the coordinate parameters included in the positioning signal of each triangular calibrator and the extension line of the azimuth angle of the bottom surface of the triangular pyramid of the triangular calibrator to obtain the adjusted coordinates.

[0079] For a single triangular calibrator, there may be multiple Beidou positioning devices in the Beidou positioning module, so there are multiple values of the coordinate parameters collected. The adjustment calculation is required to determine the most accurate value as the adjusted coordinates. Here, after the control computer obtains the coordinate parameters included in the positioning signal, the triangular relationship between each vertex can be established in the SAR calibrator network, and each vertex is connected by edges.

[0080] For each triangular calibrator, considering that the side length of the bottom surface of the triangular pyramid of the triangular calibrator is short and cannot meet the requirement for the baseline length during orientation, the extension line of the azimuth angle of the bottom surface of the triangular pyramid of the triangular calibrator can be determined. Under the condition of meeting the requirement for the baseline length, the corresponding azimuth angle can be determined according to the direction of the extension line of the azimuth angle. In addition, it is also necessary to determine the baseline position parameters between adjacent triangular calibrators (that is, the triangular calibrators with edge connections in the SAR calibrator network). Generally speaking, the baseline refers to the connection line between two transceivers (or receivers) on the earth's surface. Here, the baseline position parameters are the coordinate parameters between two adjacent triangular calibrators, that is, the baseline distance.

[0081] Then, according to the coordinate parameters, baseline distance, and azimuth angle of the triangular calibrator, the coordinates of the triangular calibrator are recalculated to obtain an equation. The recalculated coordinates of the triangular calibrator are then used for adjustment to obtain the adjusted coordinates.

[0082] For a simple example, the coordinate parameters of the triangular calibrator are (x, y), the baseline distance is s, the azimuth angle is w, and the recalculated coordinates are (X, Y). Then the equation constructed is (X, Y) = (x, y) + (s·cos(w), s·sin(w)).

[0083] In the SAR calibrator network, the attitude adjustment of a certain triangular calibrator requires determining three rotation angle parameters on the X - Y - Z axes of the azimuth angle. Then, by constructing equations with other adjacent triangular coordinators in the SAR calibrator network, three equations can be constructed according to the coordinate parameters to form a system of equations.

[0084] Here, multiple coordinate parameters collected by the Beidou positioning module are substituted into the system of equations, and calculations are performed through the method of measurement adjustment to solve for the three rotation angle parameters on the X - Y - Z axes. At the same time, the adjusted coordinates of the triangular calibrator can also be recalculated. For example, by substituting multiple coordinate parameters of (x, y) into the system of equations, the ultimate goal is to calculate the adjusted coordinates (X, Y).

[0085] Next, according to the adjusted coordinates, the azimuth angle baseline data of the triangular calibrator are determined. According to the adjusted coordinates of the triangular calibrator, the baseline (connected edge) between every two adjacent vertices can be calculated in the SAR calibrator network. This baseline has an azimuth angle, and this azimuth angle is the azimuth angle baseline data between two adjacent triangular calibrators.

[0086] Thus, according to the actual azimuth angle and azimuth angle baseline data included in the attitude measurement signal of each triangular calibrator, the azimuth angle adjustment amount is calculated. By comparing the actual azimuth angle collected by the triaxial sensor with the azimuth angle baseline data of the triangular calibrator, the azimuth angle adjustment amount can be determined, that is, the azimuth angle that the triangular calibrator needs to be adjusted, that is, the degree of attitude adjustment.

[0087] The attitude adjustment of the triangular calibrator is realized by driving the servo motor of the positioning base. Therefore, finally, the azimuth angle adjustment amount is converted into the step amount of the servo motor as the result of attitude calculation.

[0088] In the embodiment of the present invention, the remote control computer receives in real time the coordinate parameters included in the positioning signal of the triangular calibrator and the actual azimuth angle included in the attitude measurement signal to perform attitude calculation, realizing the automatic calculation of the attitude adjustment amount of the triangular calibrator. When determining the adjusted coordinates, if the number of triangular calibrators is sufficient, through adjustment calculation, gross errors can be well eliminated through redundant equations, and the solution accuracy of the result can be improved, making the calculated adjusted result stable.

[0089] In some embodiments, the remote control computer is further configured to compare the azimuth angle adjustment amount with a preset tolerance after calculating the azimuth angle adjustment amount. Since the azimuth angle adjustment of the triangular calibrator is limited to a certain range, when the degree of azimuth angle adjustment required is greater than this range, the automatic adjustment by the remote control computer cannot be fully realized.

[0090] Therefore, in the embodiment of the present invention, this range is set as the tolerance, that is, as the adjustment threshold of the azimuth angle adjustment amount. When the azimuth angle adjustment amount is greater than the preset tolerance, a warning signal is sent, and at this time, manual adjustment is required to enable at least the staff to conduct on-site inspections through the warning.

[0091] When the azimuth angle adjustment amount is less than the preset tolerance, it means that the azimuth angle adjustment of the triangular calibrator is within the range, and the automatic adjustment by the remote control computer can be realized. After completing the attitude adjustment, continue to perform measurement adjustment calculation in the SAR calibrator network to obtain the adjusted coordinates until the actual azimuth angle included in the attitude measurement signal of the triangular calibrator is adjusted to be the same as the azimuth angle baseline data.

[0092] In the embodiment of the present invention, during the automatic adjustment of the remote control computer, the limited range of attitude adjustment is reasonably determined, and different adjustment means are adopted for different azimuth angle adjustment amounts, thereby solving the problem of high-precision automatic positioning and orientation of a single triangular calibrator within the SAR calibrator network.

[0093] In some embodiments, after the controller in each triangular calibrator receives a control instruction signal, it will drive the servo motor to adjust the attitude of the triangular calibrator. The following describes the process of the servo motor adjusting the attitude of the triangular calibrator.

[0094] First, in the control instruction signal, the remote control computer has already converted the azimuth adjustment amount into the step amount of the servo motor. Therefore, here, the link rod is directly adjusted according to the step amount of the servo motor included in the control instruction signal to adjust the rotation angle parameter of the triangular calibrator. The step amount of this servo motor can be divided into the step amount of the rolling servo motor and the step amount of the attitude control servo motor. Taking Figure 8 the positioning base as an example, the slide rail vehicle is driven to slide on the circular rail by the step amount of the rolling servo motor, and the step amount of the attitude control servo motor rotates the thread of the connecting rod sleeve to realize the lifting of the calibrator section of the link rod. The attitude control servo motor can control the rotation of the thread of the connecting rod sleeve, thereby realizing the lifting of the entire link rod, and further changing the direction attitude of the bottom surface of the triangular pyramid of the triangular calibrator. The change of the reverse attitude will change the azimuth angle, resulting in the change of the rotation angle parameter.

[0095] As Figure 9 shown, the rotation angle parameter includes the heading angle, pitch angle, and roll angle in the three-axis direction, corresponding to the Z-axis, X-axis, and Y-axis directions of the bottom surface of the triangular pyramid of the triangular calibrator respectively. The rotation angle parameters in these three directions are the actual azimuth angles collected by the three-axis sensor.

[0096] In the embodiment of the present invention, the movement of the slide rail vehicle and the automatic lifting of the link rod are realized through the control instruction signal of the remote control computer, changing the rotation angle parameter, thereby realizing the automatic adjustment of the direction attitude of each triangular calibrator in the SAR calibrator network.

[0097] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that they can still modify the technical solutions recorded in the foregoing embodiments, or perform equivalent replacements for some of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A SAR calibrator attitude automatic monitoring and adjustment device, characterized in that: include: SAR calibrator networking, three-axis sensor module, Beidou positioning module, 4G data transmission module, programmable board, remote control computer, power supply system; The SAR calibrator network is composed of a plurality of triangular calibrators, the outer edge of the triangular cone bottom surface of the triangular calibrator is parallel to the flight route, and the line connecting the center of the opening surface of the triangular calibrator and the vertex of the triangular cone of the triangular calibrator is perpendicular to the flight route space, and the triangular cone bottom surface of each triangular calibrator is fixedly mounted with a triaxial sensor included in the triaxial sensor module, the Y-axis direction of the triaxial sensor is perpendicular to the outer edge of the triangular cone bottom surface, the X-axis is on the triangular cone bottom surface and perpendicular to the Y-axis, and the Z-axis is perpendicular to the X-axis and Y-axis of the triangular cone bottom surface; A positioning base is installed below the triangular scaler, and a servo motor is installed on the positioning base. The positioning base is fixedly connected to the bottom surface of the triangular cone of the triangular scaler through a link rod; The Beidou positioning device included in the Beidou positioning module is installed at the vertex of the triangular cone of one or more triangular calibrators in the SAR calibrator network; The programmable board is installed on the remote control computer, and the programmable board is remotely connected with the three-axis sensor module, the Beidou positioning module, the 4G data transmission module and the controller installed on the triangulation calibrator respectively; The power supply system is electrically connected to the Beidou positioning module, the three-axis sensor module and the 4G data transmission module respectively.

2. The SAR calibrator attitude automatic monitoring and adjustment device according to claim 1 is characterized in that: A level bubble is also installed on the bottom surface of the triangular cone of the triangular calibrator, and a buckle structure is installed on the side surface of the triangular cone of the triangular calibrator. The buckle structure is used to connect a controller, and the controller is communicatively connected with the servo motor.

3. The SAR calibrator attitude automatic monitoring and adjustment device according to claim 2 is characterized in that: The positioning base installed below the triangular calibrator includes a rotating disk, which is used to rotate the triangular calibrator in the horizontal direction. Three horizontal adjustment knobs are installed on the back of the rotating disk, and the horizontal adjustment knobs are used to fix the rotating disk in a horizontal state.

4. The SAR calibrator attitude automatic monitoring and adjustment device according to claim 2, characterized in that: The positioning base installed below the triangulator includes a circular rail and three slide rail vehicles; The bottom surface of the triangular cone of the triangular calibrator is fixedly connected to the three slide rail vehicles through three connecting rods, and the three slide rail vehicles are installed on the circular rail.

5. The SAR calibrator attitude automatic monitoring and adjustment device according to claim 4 is characterized in that: The positioning base installed below the triangular calibrator also includes a connecting rod sleeve. Each connecting rod adopts a three-section structure, and each section of the connecting rod is connected by a thread of the connecting rod sleeve.

6. The SAR calibrator attitude automatic monitoring and adjustment device according to claim 5, characterized in that: The servo motors installed on the positioning base include a rolling servo motor and three posture control servo motors. The rolling servo motor is installed on any one of the slide rail vehicles, and the three posture control servo motors are installed on three connecting rods respectively.

7. The SAR calibrator attitude automatic monitoring and adjustment device according to claim 1, characterized in that: In the SAR calibrator network, a three-axis sensor installed on each triangulation calibrator is used to collect attitude measurement signals of the triangulation calibrator; The Beidou positioning module is used to collect the positioning signal of each triangulator; The programmable board is used to send the posture measurement signal and the positioning signal to the remote control computer for posture calculation through the 4G data transmission module; The remote control computer is used to send a control command signal according to the result of the posture calculation; The programmable board is also used to receive the control command signal through the 4G data transmission module and send the control command signal to the controller in each triangulator. The control command signal is used to drive the servo motor installed in the positioning base of the triangulator to adjust the posture of the triangulator.

8. The SAR calibrator attitude automatic monitoring and adjustment device according to claim 7, characterized in that: The posture calculation process of the remote control computer includes: Performing measurement adjustment calculation on the coordinate parameters included in the positioning signal of each triangulator and the azimuth extension line of the triangular cone bottom surface of the triangulator to obtain adjustment coordinates; Determine the azimuth baseline data of the triangulator according to the adjusted coordinates; Calculate the azimuth adjustment amount according to the actual azimuth included in the attitude measurement signal of each delta calibrator and the azimuth baseline data; The azimuth angle adjustment amount is converted into a step amount of a servo motor as a result of the posture calculation.

9. The SAR calibrator attitude automatic monitoring and adjustment device according to claim 8, characterized in that: The remote control computer is also used to compare the azimuth angle adjustment amount with a preset limit difference after calculating the azimuth angle adjustment amount; When the azimuth angle adjustment amount is greater than a preset limit error, a warning signal is sent.

10. The SAR calibrator attitude automatic monitoring and adjustment device according to claim 7, characterized in that: The process of the servo motor adjusting the posture of the triangulator includes: The link rod is adjusted according to the step amount of the servo motor included in the control command signal to adjust the rotation angle parameters of the triangulator, wherein the rotation angle parameters include the heading angle, the pitch angle and the roll angle in the three-axis directions.

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