Amphibious aircraft phased array meteorological radar installation and calibration method

Abstract

The invention provides an amphibious aircraft phased array meteorological radar installation and calibration method. The method comprises the step of installing a calibration tool and a laser borescope. Tracking N horizontal measurement points on an airplane body through a laser tracking system, and creating a current full-airplane coordinate system in a ground target station; calibrating a theoretical coordinate position of a calibration mirror laser emission point based on a machine body and a calibration tool digital model in a full-machine coordinate system; correcting the position of the cursor plate; calibrating the aiming position of the target mirror and inputting a calibration result, starting a borescope laser, calibrating the aiming position of the target mirror on a cursor plate plane, recording data obtained in the calibration process, and inputting the calibration result obtained through calculation into a radar computer so as to complete the whole calibration process. According to the invention, the problem of high manpower, material resource and time cost in the ground calibration process after the airborne phased array meteorological radar is installed can be solved, and the problem of difficult calibration after the radar of an amphibious aircraft is reloaded in a non-open flat ground environment in the later period can also be solved.

Description

Technical Field

[0001] The invention relates to the technical field of calibration and correction of amphibious aircraft, and in particular to an installation and calibration method of a phased array weather radar of an amphibious aircraft. Background Art

[0002] As phased array technology is widely used in radar, communication and other fields and develops rapidly, the active phased array weather radar carried by a certain type of amphibious aircraft also has outstanding advantages in anti-interference ability, detection accuracy, functional diversity, etc. At the same time, compared with traditional radars that use mechanical methods to rotate radar antennas, phased array radars change the direction of the beam for scanning by arranging multiple radiating components on a flat antenna and controlling the current of the radiating units with an electronic computer, thus achieving long-distance, multi-target, high-sensitivity and high-precision scanning detection. This places higher requirements on the accuracy of the calibration of the phased array weather radar system errors.

[0003] Airborne weather radars need to be calibrated on the ground after installation. The calibration is mainly aimed at the flatness of the radar antenna base and the mounting surface, as well as the parallelism of the entire active phased antenna array and the mounting surface, the verticality with the pitch axis, and the verticality with the horizontal plane. The traditional design method of radar calibration: mainly uses antenna array telescopes and cursor boards to measure the horizontal (vertical) deviation between the antenna optical axis and the antenna mechanical axis. This test method is easier to find the verticality and horizontality of the radar turntable and the cursor board bracket for ground-based radar calibration, and then adjust the angle of the antenna and the cursor board to make them parallel. After the airborne weather radar is installed, the fuselage is used as a turntable, and the workload of finding and adjusting the level of the fuselage is very large. Manually adjusting the level of the fuselage requires a lot of manpower and material resources, and takes a lot of time. The verticality of the cursor board bracket is also difficult to guarantee, which affects the measurement accuracy and results of the calibration equipment. Summary of the invention

[0004] The purpose of the present invention is to provide an installation and calibration method for a phased array weather radar for an amphibious aircraft in view of the shortcomings of the above-mentioned traditional radar calibration method, which can solve the problems of high manpower, material and time costs in the ground calibration process of the airborne phased array weather radar after installation, and can also solve the problem of difficulty in calibration after radar replacement of amphibious aircraft in a non-open flat environment in the later stage.

[0005] The present invention achieves the above-mentioned purpose through the following technical solutions:

[0006] A method for calibrating an amphibious aircraft phased array weather radar installation, the method comprising the following steps:

[0007] Install calibration fixture and laser calibration target mirror;

[0008] Track N horizontal measurement points on the aircraft fuselage through the laser tracking system, and create the current aircraft full-machine coordinate system in the ground target station;

[0009] In the whole aircraft coordinate system, the theoretical coordinate position of the laser emission point of the calibration mirror is calibrated based on the digital model of the aircraft body and the calibration tooling;

[0010] Correcting the cursor board position, including: placing a spherical reflector, tracking coordinates and correcting the position, and adjusting the cursor board plane;

[0011] Calibrate the aiming position of the target scope and input the calibration results, turn on the laser calibration target scope, calibrate the aiming position of the laser calibration target scope on the cursor plane, record the data obtained during the calibration process, and input the calculated calibration results into the radar computer to complete the entire calibration process.

[0012] According to the present invention, a method for installing and calibrating an amphibious aircraft phased array weather radar, the installation and calibration tooling and the laser calibration target mirror include:

[0013] Install the calibration tooling vertically above the weather radar, and install the laser calibration mirror offset on the top of the antenna, with its azimuth direction consistent with the direction of the aircraft body, to ensure that the emission direction of the laser beam is consistent with the flight direction of the aircraft;

[0014] The reference of the installation fixing point coincides with the symmetry axis of the aircraft, and the error angle is less than 15'.

[0015] According to a method for calibrating an amphibious aircraft phased array weather radar installation provided by the present invention, the method tracks N horizontal measurement points on the aircraft fuselage by a laser tracking system, comprising:

[0016] Ten horizontal measurement points on the aircraft fuselage are selected as the target point distribution points for establishing the coordinate system, including four horizontal measurement points on the bottom of the amphibious aircraft hull, located at 1 left and 1 right of the nose and 2 left and 2 right of the tail; there are six horizontal measurement points on the aircraft fuselage, located at 3 left and 3 right and 4 left and 4 right of the nose and 5 left and 5 right of the tail.

[0017] According to a method for calibrating an amphibious aircraft phased array weather radar installation provided by the present invention, the method of creating a current aircraft full-machine coordinate system in a ground target station comprises:

[0018] Use the ground target station software platform to establish the full aircraft coordinate system:

[0019] Establish a horizontal plane based on 3left, 3right and 4left points;

[0020] The whole machine symmetry plane is established based on the left and right midpoints of 1 and 2 and the left and right midpoints of 2;

[0021] The horizontal plane and symmetry plane of the wing establish the coordinate system of the entire aircraft.

[0022] According to the present invention, a method for calibrating the installation of an amphibious aircraft phased array weather radar, the method of calibrating the theoretical coordinate position of the emission point of the laser calibration scope comprises:

[0023] According to the digital-analog connection relationship between the laser calibration mirror and the aircraft body, the theoretical coordinate position (Dx, Dy, Dz) of the laser emitting point of the laser calibration mirror is calibrated according to the origin (0, 0, 0) of the global coordinate system established by the target station software platform, and the pitch offset distance Dz of the target mirror is obtained. This distance represents the offset of the laser emitting point in the vertical direction relative to the origin of the global coordinate system.

[0024] According to the present invention, a method for calibrating an amphibious aircraft phased array weather radar installation, the calibration of the cursor position includes:

[0025] Place a spherical reflector at the origin, horizontal line, and vertical line of the cursor board as the target point of the laser tracking system;

[0026] Use a laser tracking system to track the coordinates of the spherical reflector on the cursor board, including (x0, y0, z0) at the origin, (xh, yh, zh) at the horizontal line, and (xv, yv, zv) at the vertical line;

[0027] According to the tracked coordinates, the offset of the cursor board relative to the whole aircraft coordinate system is calculated to correct the cursor board position, so that the cursor board is at the position required by the radar calibration distance, that is, the origin of the cursor board coincides with the origin of the whole aircraft coordinate system;

[0028] Adjust the plane of the cursor board so that the axis of the aircraft on the cursor board coincides with the axis of the aircraft body, and adjust the position and attitude of the cursor board so that the cursor board is perpendicular to the axis of the aircraft body;

[0029] Make sure the cursor plane is parallel to the antenna radiating surface.

[0030] According to the installation calibration method of an amphibious aircraft phased array weather radar provided by the present invention, when placing a spherical reflector, four fixed adjustment points of the cursor plate are designated as fixed positions of the spherical reflector, which are respectively located at the origin, the horizontal line, and the vertical line, and are proposed to be the origin O, point A, point B, and point C;

[0031] A laser tracking system is used to track the coordinates of the spherical reflectors at the origin O and points A, B, and C on the cursor board. During the process of adjusting the plane of the cursor board, the coordinate data of the target station software platform is monitored in real time.

[0032] According to the installation calibration method of an amphibious aircraft phased array weather radar provided by the present invention, the Z-axis coordinate value of the spherical reflector at the origin O and A, C on the cursor board is 0;

[0033] The Y-axis coordinate value of the spherical reflector at the origin O and B on the cursor board is 0

[0034] The X-axis coordinate values ​​of the spherical reflector at the origin O and A, B, and C on the cursor board meet the conditions: Ro = RA = RB = RC = Rr;

[0035] The axis of the aircraft on the cursor board coincides with the axis of the aircraft body, the cursor board is perpendicular to the axis of the aircraft body, and the plane of the cursor board is parallel to the antenna radiation surface.

[0036] According to the installation calibration method of an amphibious aircraft phased array weather radar provided by the present invention, during the calibration process, by turning on the infrared switch on the calibration target scope, a red dot is obtained on the cursor board plane, the actual aiming position of the calibration target scope is calibrated, the position of the red dot on the cursor board is compared with the predetermined aiming point, and the aiming angle of the calibration target scope is adjusted until the red dot coincides with the aiming point;

[0037] Record the calibration data, substitute the recorded calibration data into the calculation formula, repeat the calibration multiple times, and input the results of multiple calibrations into the radar computer to obtain the final aiming position parameters.

[0038] According to an installation calibration method for an amphibious aircraft phased array weather radar provided by the present invention, during the calibration process of the weather radar, the horizontal distance between the actual aiming center of the calibration target mirror and the theoretical aiming center is set to Eaz, and the vertical distance is set to Eel. The calculation formula includes:

[0039] Azimuth error = atan(Eaz / R);

[0040] Pitch error = atan(Eel / R);

[0041] Radar antenna cursor plate distance R, R = Rr + Dx;

[0042] Connect the debugging computer to the radar and write the calculated azimuth error and elevation error into the radar processing unit to complete the calibration of the weather radar.

[0043] It can be seen that the present invention has the following beneficial effects:

[0044] 1. The present invention uses a laser tracking system to accurately track N horizontal measurement points on the aircraft fuselage, and can create a high-precision coordinate system of the current aircraft, ensuring the basic accuracy of subsequent calibration work and helping to improve the overall performance of the radar system.

[0045] 2. The entire calibration process of the present invention combines digital modeling (such as the digital model of the machine body and calibration tooling) and automated measurement technology (such as laser tracking and coordinate correction), which reduces human errors and improves calibration efficiency and accuracy. At the same time, the use of digital models also makes the calibration process more intuitive and easy to understand.

[0046] 3. The steps of correcting the cursor plate position in the method of the present invention include placing a spherical reflector, tracking coordinates and correcting the position, and adjusting the cursor plate plane. These steps show a high degree of flexibility and can cope with the challenges of different aircraft shapes and installation conditions to ensure the accuracy and reliability of calibration.

[0047] 4. The data obtained during the calibration process of the present invention is recorded in detail, and the calculated calibration results are input into the radar computer, which not only facilitates subsequent analysis and review, but also improves the traceability of the calibration results, which is helpful for problem troubleshooting and performance optimization.

[0048] 5. Strong adaptability: This method is not only applicable to amphibious aircraft, but its basic principles and technical means can also be extended to the calibration of other types of aircraft and radar systems, showing good adaptability and versatility.

[0049] 6. Through precise calibration, the present invention can ensure that the phased array weather radar can maintain high performance operation under complex meteorological conditions and various flight conditions, improve the accuracy and reliability of meteorological observation, and provide strong guarantee for flight safety.

[0050] The present invention is further described in detail below in conjunction with the accompanying drawings and specific embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0051] Figure 1 The present invention is a flow chart of an embodiment of a method for calibrating an amphibious aircraft phased array weather radar installation.

[0052] Figure 2 It is a schematic diagram of arranging laser spherical reflectors at various distribution points on a fuselage in an embodiment of an installation and calibration method for an amphibious aircraft phased array weather radar of the present invention.

[0053] Figure 3 The present invention is a schematic diagram of a target scope and a weather radar in an embodiment of an installation and calibration method for an amphibious aircraft phased array weather radar.

[0054] Figure 4 The present invention is a schematic diagram of the position distribution of a spherical reflector on a cursor plate in an embodiment of an installation and calibration method for an amphibious aircraft phased array weather radar.

[0055] Figure 5The present invention is a schematic diagram of how to adjust the plane of the cursor plate in an embodiment of an installation calibration method for an amphibious aircraft phased array weather radar.

[0056] Figure 6 It is a schematic diagram of calculating the installation error of the radar antenna in an embodiment of an installation calibration method for an amphibious aircraft phased array weather radar of the present invention.

[0057] Figure 7 The invention discloses a schematic diagram of the installation of a calibration tool in an embodiment of an installation calibration method for an amphibious aircraft phased array weather radar.

[0058] Figure 8 The present invention is a schematic diagram of calibrating the theoretical horizontal plane and vertical axis of an amphibious aircraft phased array weather radar installation calibration method embodiment of the present invention. DETAILED DESCRIPTION

[0059] In order to make the purpose, technical solution and advantages of the present invention clearer, the technical solution of the present invention will be clearly and completely described below in conjunction with the drawings of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0060] Reference to "embodiments" herein means that a particular feature, structure, or characteristic described in conjunction with the embodiments may be included in at least one embodiment of the present application. The appearance of the phrase in various locations in the specification does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment that is mutually exclusive with other embodiments. It is explicitly and implicitly understood by those skilled in the art that the embodiments described herein may be combined with other embodiments.

[0061] See also Figures 1 to 8 This embodiment provides an installation and calibration method for an amphibious aircraft phased array weather radar, the method comprising the following steps:

[0062] Step S1, installing the calibration tooling and the laser calibration target mirror.

[0063] Step S2, tracking N horizontal measurement points on the aircraft fuselage by a laser tracking system, and creating a current aircraft full-machine coordinate system in a ground target station.

[0064] Step S3, calibrating the theoretical coordinate position of the calibration laser emission point in the whole machine coordinate system based on the machine body and the calibration fixture digital model.

[0065] Step S4, correcting the position of the cursor board, includes: placing a spherical reflector, tracking coordinates and correcting the position, and adjusting the plane of the cursor board.

[0066] Step S5, calibrate the aiming position of the target mirror and input the calibration result, turn on the laser calibration target mirror, calibrate the aiming position of the target mirror on the cursor plane, record the data obtained during the calibration process, and input the calculated calibration result into the radar computer to complete the entire calibration process.

[0067] It can be seen that the present invention can solve the problem of high manpower, physical force and time costs in the process of leveling the aircraft during the calibration of the airborne meteorological radar, and can also solve the problem of restrictions on the flatness requirements of the radar calibration site.

[0068] Among them, this embodiment realizes accurate modeling of the entire coordinate system of the current aircraft through data import and preprocessing of steps S1 and S2; through step S3, it realizes rapid positioning of the target mirror laser emission point; through step S4, it realizes spatial leveling of the cursor calibration target plate and the radar antenna, reducing the workload of aircraft leveling, thereby saving costs and improving the efficiency and accuracy of calibration processing; through step S5, the platform's quick calibration inspection method is used, which has strong repeatability, and can be calibrated multiple times to take the average, avoiding errors and inefficiencies introduced by human factors, and ensuring the reliability of the calibration results.

[0069] In the above step S1, installing the calibration fixture and the laser calibration target mirror includes:

[0070] The calibration tool is installed vertically above the weather radar, and the laser calibration mirror is offset on the top of the antenna, and its azimuth direction is consistent with the direction of the aircraft body (along the heading) to ensure that the emission direction of the laser beam is consistent with the flight direction of the aircraft, thereby improving the accuracy of the calibration.

[0071] The reference of the installation fixing point coincides with the symmetry axis of the aircraft, and the error angle is less than 15'.

[0072] For the coincidence requirement between the reference of the installation fixed point and the symmetry axis of the aircraft, the symmetry axis of the aircraft can be accurately measured and marked before installation. Then, during the installation process, high-precision measurement tools (such as laser trackers, total stations, etc.) are used to monitor and calibrate the position and direction of the installation fixed point to ensure that the coincidence with the symmetry axis of the aircraft meets the requirements.

[0073] In the above step S2, tracking N horizontal measurement points on the aircraft fuselage by a laser tracking system includes:

[0074] A laser tracking system (ranging accuracy 0.025 mm) was selected, and 10 horizontal measurement points on the fuselage of the aircraft were selected as the target point distribution points for establishing the coordinate system. These points were used to determine the spatial position and direction of the aircraft, including 4 horizontal measurement points on the bottom of the amphibious aircraft hull, located at 1 left and 1 right of the nose and 2 left and 2 right of the tail; there were 6 horizontal measurement points on the fuselage of the aircraft, located at 3 left and 3 right and 4 left and 4 right of the nose and 5 left and 5 right of the tail, and laser spherical reflectors were arranged at each distribution point, such as Figure 2 shown.

[0075] Specifically, the four horizontal measurement points on the bottom of the amphibious aircraft hull include:

[0076] Nose position: 1 left, 1 right, these two points are located on the left and right sides of the nose respectively, and are used to determine the horizontal position and direction of the nose.

[0077] Tail position: 2 Left, 2 Right, these two points are located on the left and right sides of the tail, corresponding to the measurement points on the nose, and are used to determine the horizontal position and direction of the tail and help establish the overall length and symmetry of the aircraft.

[0078] 6 horizontal measurement points on the aircraft fuselage:

[0079] Nose position: 3 left, 3 right. These two points are located slightly behind the nose and complement the 1 left and 1 right points on the bottom of the hull to further refine the position and shape of the nose.

[0080] Middle fuselage: 4 Left, 4 Right, these two points are located on the left and right sides of the middle fuselage and are used to determine the horizontal position and direction of the middle fuselage, helping to establish the overall width and symmetry of the aircraft.

[0081] Tail position: 5 left and 5 right. These two points are located slightly in front of the tail and correspond to points 2 left and 2 right on the bottom of the hull, further refining the position and shape of the tail.

[0082] In the above step S2, the current aircraft full-machine coordinate system is created in the ground target station, including:

[0083] Use the ground target station software platform to establish the full aircraft coordinate system:

[0084] Establish a horizontal plane based on 3left, 3right and 4left points;

[0085] The whole machine symmetry plane is established based on the left and right midpoints of 1 and 2 and the left and right midpoints of 2;

[0086] The horizontal plane and symmetry plane of the wing establish the coordinate system of the entire aircraft.

[0087] In the above step S3, the theoretical coordinate position of the emission point of the laser calibration mirror is calibrated, including:

[0088] According to the digital-analog connection relationship between the laser calibration mirror and the aircraft body, the theoretical coordinate position (Dx, Dy, Dz) of the laser emission point of the calibration mirror is calibrated according to the origin (0, 0, 0) of the whole aircraft coordinate system established by the target station software platform, and the pitch offset distance Dz of the target mirror is obtained, as follows: Figure 3 As shown, the distance represents the offset of the laser emission point in the vertical direction relative to the origin of the global aircraft coordinate system.

[0089] In the above step S4, the position of the cursor pad is corrected, including:

[0090] Place a spherical reflector at the origin, horizontal line, and vertical line of the cursor board as the target point of the laser tracking system;

[0091] Use a laser tracking system to track the coordinates of the spherical reflector on the cursor board, including (x0, y0, z0) at the origin, (xh, yh, zh) at the horizontal line, and (xv, yv, zv) at the vertical line;

[0092] According to the tracked coordinates, the offset of the cursor board relative to the whole aircraft coordinate system is calculated to correct the cursor board position, so that the cursor board is at the position required by the radar calibration distance, that is, the origin of the cursor board coincides with the origin of the whole aircraft coordinate system;

[0093] Adjust the plane of the cursor board so that the axis of the aircraft on the cursor board coincides with the axis of the aircraft body, and adjust the position and attitude of the cursor board so that the cursor board is perpendicular to the axis of the aircraft body;

[0094] Make sure the cursor board plane is parallel to the antenna radiating surface. This can be checked by placing a reference plane on the cursor board that is parallel to the antenna radiating surface and observing the gap or reflection between the two.

[0095] In the above step S4, when placing the spherical reflector, four fixed adjustment points of the cursor plate are designated as fixed positions of the spherical reflector, which are located at the origin, the horizontal line, and the vertical line, and are proposed to be the origin O, point A, point B, and point C. Figure 4 shown.

[0096] Preferably, in step S4, a laser tracking system is used to track the coordinates of the origin O and the spherical reflectors at points A, B and C on the cursor board, and during the process of adjusting the plane of the cursor board, the coordinate data of the target station software platform is monitored in real time.

[0097] In the above step S4, the Z-axis coordinate value of the spherical reflector at the origin O and A, C on the cursor board is 0;

[0098] The Y-axis coordinate value of the spherical reflector at the origin O and B on the cursor board is 0;

[0099] The X-axis coordinate values ​​of the spherical reflector at the origin O and A, B, and C on the cursor board meet the conditions: Ro = RA = RB = RC = Rr;

[0100] The axis of the aircraft on the cursor board coincides with the axis of the aircraft body, and the cursor board is perpendicular to the axis of the aircraft body, and the plane of the cursor board is parallel to the antenna radiation surface. Figure 5 shown.

[0101] In the above step S5, during the calibration process, by turning on the infrared switch on the calibration target mirror, a red dot is obtained on the cursor board plane to calibrate the actual aiming position of the calibration target mirror, such as Figure 6 As shown in the figure, compare the position of the red dot on the cursor board with the predetermined aiming point, and adjust the aiming angle of the calibration scope until the red dot coincides with the aiming point;

[0102] Record the calibration data, substitute the recorded calibration data into the calculation formula, repeat the calibration multiple times, and input the results of multiple calibrations into the radar computer to obtain the final aiming position parameters.

[0103] During the calibration process of the meteorological radar, the horizontal distance between the actual aiming center of the calibration target mirror and the theoretical aiming center is set to Eaz, and the vertical distance is set to Eel. The calculation formula includes:

[0104] Azimuth error = atan(Eaz / R);

[0105] Pitch error = atan(Eel / R);

[0106] Radar antenna cursor plate distance R, R = Rr + Dx;

[0107] Connect the debugging computer to the radar and write the calculated azimuth error and elevation error into the radar processing unit to complete the calibration of the weather radar.

[0108] Furthermore, in the above step S1, the radar cover is removed and the calibration tooling is installed, wherein the tooling installation needs to be aligned with the meteorological radar system installation accuracy requirements including:

[0109] Installation fixing point: The reference coincides with the symmetry axis of the aircraft, and the error angle is less than 15'. The installation position is as follows Figure 7 shown.

[0110] Furthermore, in the above step S2, the whole aircraft coordinate system is established to generate a three-dimensional aircraft fuselage data model. The whole aircraft coordinate system is calibrated on the ground using a laser tracking system, a ground target station, a fuselage positioning pin and a spherical reflector, and the theoretical horizontal plane and vertical axis of the aircraft fuselage are calibrated by the horizontal measurement point distribution of the fuselage vertical tail, such as Figure 8 shown.

[0111] Specifically, when using the ground target station software platform to establish the coordinate system of the entire aircraft, first prepare a suitable target according to the requirements of the software platform. The target should have feature points or marks that are easy to identify and measure. Arrange the targets at predetermined positions on the aircraft or related structures to ensure that they can accurately reflect the geometric characteristics of the entire aircraft. Start the ground target station software platform and perform necessary initialization settings. Use the software platform to control the measurement equipment (such as laser trackers, total stations, etc.) to accurately measure the feature points on the target and record the measurement data, including the three-dimensional coordinates of each feature point.

[0112] Then, an initial coordinate system is set in the software platform. The coordinate system can be a global coordinate system or any convenient local coordinate system. The collected data is processed, including data cleaning, denoising, fitting and other operations. Based on the processed data, the relative position relationship between the feature points on the target is calculated. Using the known target position relationship and the geometric characteristics of the entire aircraft, the initial coordinate system is converted into the entire aircraft coordinate system through mathematical transformations (such as rotation, translation, etc.). The parameters of the entire aircraft coordinate system are set in the software platform, including the coordinate origin, coordinate axis direction, etc. After the entire aircraft coordinate system is established, the software platform is used to measure other known points on the aircraft or related structures, and compare them with the theoretical values ​​to verify the accuracy of the coordinate system.

[0113] In summary, the present invention can accurately track N horizontal measurement points on the aircraft fuselage through a laser tracking system, and can create a high-precision coordinate system of the entire current aircraft, ensuring the basic accuracy of subsequent calibration work, and helping to improve the overall performance of the radar system. The entire calibration process of the present invention combines digital modeling (such as fuselage and calibration tooling digital model) and automated measurement technology (such as laser tracking and coordinate correction), reducing human errors and improving calibration efficiency and accuracy. At the same time, the use of digital models also makes the calibration process more intuitive and easy to understand. The steps of correcting the position of the cursor in the method of the present invention include placing a spherical reflector, tracking coordinates and correcting the position, and adjusting the plane of the cursor. These steps show a high degree of flexibility and can cope with the challenges of different aircraft forms and installation conditions, ensuring the accuracy and reliability of calibration. The data obtained during the calibration process of the present invention is recorded in detail, and the calculated calibration results are input into the radar computer, which is not only convenient for subsequent analysis and review, but also improves the traceability of the calibration results, which is helpful for problem troubleshooting and performance optimization. This method is not only applicable to amphibious aircraft, but its basic principles and technical means can also be extended to the calibration of other types of aircraft and radar systems, showing good adaptability and versatility. Through precise calibration, the present invention can ensure that the phased array weather radar can maintain high performance under complex weather conditions and various flight conditions, improve the accuracy and reliability of weather observation, and provide strong guarantee for flight safety.

[0114] The technical features of the above embodiments may be combined arbitrarily. To make the description concise, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0115] The above-mentioned embodiments are only preferred embodiments of the present invention and cannot be used to limit the scope of protection of the present invention. Any non-substantial changes and substitutions made by technicians in this field on the basis of the present invention shall fall within the scope of protection required by the present invention.

Claims

1. A method for calibrating an amphibious aircraft phased array weather radar installation, characterized in that: The following steps are involved: Install calibration fixture and laser calibration target mirror; Track N horizontal measurement points on the aircraft fuselage through the laser tracking system, and create the current aircraft full-machine coordinate system in the ground target station; In the whole aircraft coordinate system, the theoretical coordinate position of the launch point of the laser calibration mirror is calibrated based on the aircraft body and calibration fixture digital model; Correcting the cursor board position, including: placing a spherical reflector, tracking coordinates and correcting the position, and adjusting the cursor board plane; Calibrate the aiming position of the target scope and input the calibration results, turn on the laser calibration target scope, calibrate the aiming position of the laser calibration target scope on the cursor plane, record the data obtained during the calibration process, and input the calculated calibration results into the radar computer to complete the entire calibration process.

2. The method according to claim 1, characterized in that The installation calibration tool and laser calibration target mirror include: Install the calibration tooling vertically above the weather radar, and install the laser calibration mirror offset on the top of the antenna, with its azimuth direction consistent with the direction of the aircraft body, to ensure that the emission direction of the laser beam is consistent with the flight direction of the aircraft; The reference of the installation fixing point coincides with the symmetry axis of the aircraft, and the error angle is less than 15'.

3. The method according to claim 1, characterized in that Tracking N horizontal measurement points on the aircraft fuselage by a laser tracking system includes: Ten horizontal measurement points on the aircraft fuselage are selected as the target point distribution points for establishing the coordinate system, including four horizontal measurement points on the bottom of the amphibious aircraft hull, located at 1 left and 1 right of the nose and 2 left and 2 right of the tail; there are six horizontal measurement points on the aircraft fuselage, located at 3 left and 3 right and 4 left and 4 right of the nose and 5 left and 5 right of the tail.

4. The method according to claim 3, characterized in that The step of creating the current aircraft full-machine coordinate system in the ground target station includes: Use the ground target station software platform to establish the full aircraft coordinate system: Establish a horizontal plane based on 3left, 3right and 4left points; The whole machine symmetry plane is established based on the left and right midpoints of 1 and 2 and the left and right midpoints of 2; The horizontal plane and symmetry plane of the wing establish the coordinate system of the entire aircraft.

5. The method according to claim 1, characterized in that The method of calibrating the theoretical coordinate position of the emission point of the laser calibration mirror includes: According to the digital-analog connection relationship between the laser calibration mirror and the aircraft body, the theoretical coordinate position (Dx, Dy, Dz) of the laser emitting point of the laser calibration mirror is calibrated according to the origin (0, 0, 0) of the global coordinate system established by the target station software platform, and the pitch offset distance Dz of the target mirror is obtained. This distance represents the offset of the laser emitting point in the vertical direction relative to the origin of the global coordinate system.

6. The method according to claim 1, characterized in that The method of correcting the cursor position comprises: Place a spherical reflector at the origin, horizontal line, and vertical line of the cursor board as the target point of the laser tracking system; Use a laser tracking system to track the coordinates of the spherical reflector on the cursor board, including (x0, y0, z0) at the origin, (xh, yh, zh) at the horizontal line, and (xv, yv, zv) at the vertical line; According to the tracked coordinates, the offset of the cursor board relative to the whole aircraft coordinate system is calculated to correct the cursor board position, so that the cursor board is at the position required by the radar calibration distance, that is, the origin of the cursor board coincides with the origin of the whole aircraft coordinate system; Adjust the plane of the cursor board so that the axis of the aircraft on the cursor board coincides with the axis of the aircraft body, and adjust the position and attitude of the cursor board so that the cursor board is perpendicular to the axis of the aircraft body; Make sure the cursor plane is parallel to the antenna radiating surface.

7. The method according to claim 6, characterized in that: When placing the spherical reflector, specify 4 fixed adjustment points on the cursor plate as the fixed positions of the spherical reflector, which are located at the origin, horizontal line, and vertical line, and are proposed to be the origin O, point A, point B, and point C; A laser tracking system is used to track the coordinates of the spherical reflectors at the origin O and points A, B, and C on the cursor board. During the process of adjusting the plane of the cursor board, the coordinate data of the target station software platform is monitored in real time.

8. The method according to claim 7, characterized in that: The Z-axis coordinate value of the spherical reflector at the origin O, A, and C on the cursor board is 0; The Y-axis coordinate value of the spherical reflector at the origin O and B on the cursor board is 0 The X-axis coordinate values ​​of the spherical reflector at the origin O and A, B, and C on the cursor board meet the conditions: Ro = RA = RB = RC = Rr; The axis of the aircraft on the cursor board coincides with the axis of the aircraft body, the cursor board is perpendicular to the axis of the aircraft body, and the plane of the cursor board is parallel to the antenna radiation surface.

9. The method according to any one of claims 1 to 8, characterized in that: During the calibration process, by turning on the infrared switch on the calibration scope, a red dot is obtained on the cursor board plane, the actual aiming position of the calibration scope is calibrated, the position of the red dot on the cursor board is compared with the predetermined aiming point, and the aiming angle of the calibration scope is adjusted until the red dot coincides with the aiming point; Record the calibration data, substitute the recorded calibration data into the calculation formula, repeat the calibration multiple times, and input the results of multiple calibrations into the radar computer to obtain the final aiming position parameters.

10. The method according to claim 9, characterized in that: During the calibration process of the meteorological radar, the horizontal distance between the actual aiming center of the calibration target mirror and the theoretical aiming center is set to Eaz, and the vertical distance is set to Eel. The calculation formula includes: Azimuth error = atan(Eaz / R); Pitch error = atan(Eel / R); Radar antenna cursor plate distance R, R = Rr + Dx; Connect the debugging computer to the radar and write the calculated azimuth error and elevation error into the radar processing unit to complete the calibration of the weather radar.

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