A method and system for adjusting the shape of a spherical radio telescope active reflector

Abstract

The application belongs to the technical field of large radio telescope, and provides a kind of spherical radio telescope active reflecting surface shape adjusting method and system, first, the reference spherical radius and focal ratio are obtained, the coordinate system is updated, and the ideal parabolic surface of the observed celestial body is determined;Then, the coordinates of each node under the original coordinate system and the azimuth and elevation of the measured celestial body are obtained, and the position coordinates of each node under the new coordinate system are obtained through rotation transformation;The center of the ideal parabolic surface aperture is calculated, and the to-be-adjusted node is determined in combination with the reference spherical radius;Finally, the sum of the square of the distance between the coordinates of all to-be-adjusted nodes in the radial direction of the working parabolic surface and the ideal parabolic surface is minimized as the target, the target coordinates of all to-be-adjusted nodes are determined, and the extension amount of the top end of the actuator is calculated, so that the working parabolic surface is as close as possible to the ideal parabolic surface, to obtain the best receiving effect of the electromagnetic wave of the celestial body reflected by the reflecting surface.

Description

Technical Field

[0001] This invention belongs to the field of large radio telescope technology, and particularly relates to a method and system for adjusting the shape of the active reflector surface of a spherical radio telescope. Background Technology

[0002] The statements in this section are merely background information related to the present invention and do not necessarily constitute prior art.

[0003] The Five-hundred-meter Aperture Spherical radio Telescope (FAST), also known as the Sky Eye, is my country's largest and most sensitive single-dish radio telescope with independent intellectual property rights. FAST consists of an active reflector, a signal receiving system (feed cabin), and related control, measurement, and support systems. The active reflector system is an adjustable sphere composed of main cable nets, reflector panels, pull cables, actuators, and support structures. The main cable net is constructed of flexible main cables arranged in a geodesic triangular grid pattern to support the reflector panels (including the back frame structure). One reflector panel is installed on each triangular grid, and the entire cable net is fixed to the surrounding support structure. Each main cable node is connected to a pull cable, the lower end of which is connected to an actuator fixed to the ground surface, enabling shape control of the main cable net.

[0004] The active reflector has several main cable nodes connected by main cables. The active reflector can be divided into two states: a reference state and a working state. In the reference state, the reflector is a sphere with a radius of approximately 300 meters and a diameter of 500 meters (the reference sphere, with its center denoted as point C). All main cable nodes are located on the reference sphere, and each reflector panel is a part of the reference sphere. In the working state, the shape of the reflector is adjusted to an approximately parabolic surface of revolution with a diameter of 300 meters (the working parabolic surface). The working parabolic surface is formed by the cooperation of a pull-down cable and an actuator, with the length of the pull-down cable being fixed throughout the process. The actuator is installed radially along the reference sphere, with its bottom fixed to the ground and its top extending and retracting radially along the reference sphere to adjust the pull-down cable, thereby adjusting the position of the reflector panel.

[0005] When FAST observes a celestial target S in a certain direction, it adjusts a portion of the reflective panels on the reference sphere to form an approximate paraboloid of revolution, reflecting and converging parallel electromagnetic waves from the target celestial body into the effective area of ​​the feed cabin. Here, the axis of symmetry of the approximate paraboloid of revolution is the straight line SC, and the focal point P is the intersection of the straight line SC and the focal plane. The focal plane is a sphere concentric with the reference sphere, and the difference in radius between the two concentric spheres is F = 0.466R (where R is the radius of the reference sphere, and F / R is called the focal diameter ratio). The effective area for receiving signals in the feed cabin is a disk with a diameter of 1 meter and a midpoint at P.

[0006] During the adjustment process, the actuator's extension and retraction along the radial direction towards the center of the reference sphere is considered positive. Under the reference state, the radial extension and retraction of the actuator tip is usually required to be 0, and its radial extension and retraction range is (-ε1, ε1) meters. After the main cable node is adjusted, the distance between adjacent nodes may change slightly, with the change not exceeding ε2.

[0007] However, the current adjustment methods make it difficult to obtain the best reception effect of celestial electromagnetic waves after reflection by the reflector. Summary of the Invention

[0008] To address the technical problems mentioned above, this invention provides a method and system for adjusting the shape of the active reflector surface of a spherical radio telescope, thereby improving the accuracy of preference evolution.

[0009] To achieve the above objectives, the present invention adopts the following technical solution:

[0010] The first aspect of the present invention provides a method for adjusting the shape of the active reflecting surface of a spherical radio telescope, comprising:

[0011] Obtain the reference spherical radius and focal diameter ratio, update the coordinate system, and determine the ideal parabolic surface of the observed celestial body;

[0012] Obtain the coordinates of each node in the original coordinate system, as well as the azimuth and elevation angles of the celestial body being measured. Then, obtain the position coordinates of each node in the new coordinate system through rotation transformation.

[0013] Calculate the center of the ideal parabolic aperture and, in conjunction with the radius of the reference sphere, determine the node to be adjusted;

[0014] The target coordinates of all nodes to be adjusted are determined with the goal of minimizing the sum of the squares of the distances between the coordinates of all nodes to be adjusted in the radial direction between the working parabolic surface and the ideal parabolic surface.

[0015] Calculate the extension / retraction amount at the top of the actuator based on the position coordinates and target coordinates of all nodes to be adjusted.

[0016] Furthermore, the specific steps for obtaining the position coordinates of each node in the new coordinate system through rotation transformation are as follows:

[0017] Calculate the transformation matrix based on the azimuth and elevation angles of the measured celestial body in the original coordinate system;

[0018] Based on the transformation matrix, the coordinates of each node in the original coordinate system are rotated and transformed using the transformation formula to obtain the coordinates of each node in the new coordinate system.

[0019] Furthermore, the specific steps for determining the nodes that need adjustment are as follows:

[0020] With the center of the ideal parabolic aperture as the center, construct a sphere with the radius of the reference sphere as the diameter, derive the equation of the sphere, and obtain the set of nodes to be adjusted;

[0021] Find the equations of the lines connecting all nodes in the set to the radial direction of the sphere's center;

[0022] By combining the equation of the straight line with the equation of the ideal parabola, and then with the equation of the sphere, the position coordinates of each node to be adjusted are determined.

[0023] Furthermore, the specific method for updating the coordinate system is as follows: taking the line connecting the observed celestial body and the center of the reference sphere as the Z-axis, determining the X-axis and Y-axis according to the right-hand rule, and re-establishing a new coordinate system.

[0024] Furthermore, the receiver ratio of the feed cabin is calculated, and the reception effect after the shape of the active reflector is changed is monitored; the receiver ratio of the feed cabin is the ratio of the reflected signal received in the effective area of ​​the feed cabin to the reflected signal of the reflector within the aperture.

[0025] A second aspect of the present invention provides a spherical radio telescope active reflector shape adjustment system, comprising:

[0026] The ideal parabolic surface determination module is configured to: obtain the radius and focal diameter ratio of the reference sphere, update the coordinate system, and determine the ideal parabolic surface of the observed celestial body;

[0027] The rotation transformation module is configured to: obtain the coordinates of each node in the original coordinate system and the azimuth and elevation angles of the celestial body being measured, and obtain the position coordinates of each node in the new coordinate system through rotation transformation;

[0028] The module for determining the node to be adjusted is configured to: calculate the center of the ideal parabolic aperture and, in conjunction with the radius of the reference sphere, determine the node to be adjusted;

[0029] The target coordinate determination module is configured to determine the target coordinates of all nodes to be adjusted by minimizing the sum of the squares of the distances between the coordinates of all nodes to be adjusted in the radial direction between the working parabolic surface and the ideal parabolic surface.

[0030] The actuator tip extension / retraction calculation module is configured to calculate the actuator tip extension / retraction based on the position coordinates and target coordinates of all nodes to be adjusted.

[0031] Furthermore, after obtaining the actuator tip extension / retraction amount, the actuator tip extension / retraction amount calculation module distributes each actuator tip extension / retraction amount to the corresponding node controller in the form of control commands.

[0032] The node controller controls the motor to rotate according to the control command, thereby changing the length of the pull cable, forcing the connected node positions to change, and the changes in the positions of multiple nodes ultimately change the shape of the active reflective surface.

[0033] Furthermore, it also includes a monitoring module, which is configured to: calculate the receiver ratio of the feed cabin and monitor the reception effect after the shape of the active reflector changes; the receiver ratio of the feed cabin is the ratio of the reflected signal received in the effective area of ​​the feed cabin to the reflected signal of the reflector within the aperture.

[0034] A third aspect of the present invention provides a computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the steps of the above-described method for adjusting the shape of an active reflector surface of a spherical radio telescope.

[0035] A fourth aspect of the present invention provides a computer device including a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the program to implement the steps in the above-described method for adjusting the shape of an active reflector surface of a spherical radio telescope.

[0036] Compared with the prior art, the beneficial effects of the present invention are:

[0037] This invention provides a method for adjusting the shape of the active reflector surface of a spherical radio telescope. Under the constraint of the reflector panel adjustment, an ideal parabolic surface is determined. Then, by adjusting the radial extension of the actuator, the reflector surface is adjusted to a working parabolic surface, so that the working parabolic surface is as close as possible to the ideal parabolic surface, so as to obtain the best reception effect of celestial electromagnetic waves after reflection by the reflector surface. Attached Figure Description

[0038] The accompanying drawings, which form part of this invention, are used to provide a further understanding of the invention. The illustrative embodiments of the invention and their descriptions are used to explain the invention and do not constitute an improper limitation of the invention.

[0039] Figure 1 This is a schematic diagram of the coordinate transformation of the observed celestial body in Embodiment 1 of the present invention;

[0040] Figure 2 This is a cross-sectional schematic diagram of the spherical radio telescope according to Embodiment 1 of the present invention;

[0041] Figure 3 This is a schematic diagram showing the intersection of the mapping triangle and the effective area of ​​the feed cabin in Embodiment 1 of the present invention. Detailed Implementation

[0042] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0043] It should be noted that the following detailed description is illustrative and intended to provide further explanation of the invention. Unless otherwise specified, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains.

[0044] It should be noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the scope of exemplary embodiments according to the invention. As used herein, the singular form is intended to include the plural form as well, unless the context clearly indicates otherwise. Furthermore, it should be understood that when the terms "comprising" and / or "including" are used in this specification, they indicate the presence of features, steps, operations, devices, components, and / or combinations thereof.

[0045] Example 1

[0046] like Figure 1 As shown, this embodiment provides a method for adjusting the shape of the active reflector surface of a spherical radio telescope. Under the constraint of the reflector panel adjustment, an ideal parabolic surface is determined. Then, by adjusting the radial extension and retraction of the actuator, the reflector surface is adjusted to a working parabolic surface, making the working parabolic surface as close as possible to the ideal parabolic surface, so as to obtain the best reception effect of celestial electromagnetic waves after reflection by the reflector surface. The specific process includes:

[0047] Step 1: Obtain the radius and focal diameter ratio of the reference sphere, update the coordinate system, and determine the ideal parabolic surface of the observed celestial body directly above the reference sphere.

[0048] Step 101: Establish a new direct coordinate system

[0049] Since both spheres and parabolas are homogeneous (isotropic), this invention transforms a three-dimensional spatial problem into a two-dimensional spatial problem for solution. A circular arc is used to replace the reference sphere, and a parabola is used to replace the working parabola. The center of the reference sphere is taken as the origin of the coordinate axis, and a straight line parallel to the normal of the reference sphere and passing through the origin O is taken as the Z-axis. The X-axis and Y-axis are determined according to the right-hand rule.

[0050] Step 102: Using the line connecting the observed celestial body S and the center of the reference sphere as the Z-axis, determine the X-axis and Y-axis according to the right-hand rule, and re-establish a new direct coordinate system; determine the ideal parabolic surface of the observed celestial body S directly above the reference sphere, that is, determine the ideal parabolic surface under the new direct coordinate system.

[0051] Let the radius of the reference sphere and the diameter of the working parabola both be R, P be the focal length of the parabola, and h be the absolute distance from the lowest point of the ideal parabola to the reference parabola, where h = |z1 + R|, and z1 is the coordinate of the vertex of the ideal parabola in the z-direction. The equation of the parabola of revolution is...

[0052]

[0053] In one implementation, the radius of the reference sphere and the diameter of the working parabolic surface are both R = 300 meters and h = |z1 + 300|.

[0054] When celestial body S is directly above the reference sphere, i.e., α = 0° and β = 90°, the focus of the parabola always lies on the focal plane, which is a sphere concentric with the reference sphere. The difference in radius between the two concentric spheres is F = 0.466R (where R is the radius of the reference sphere, and F / R is called the focal diameter ratio); therefore, the focal length of the parabola can be obtained as P = -z1 - 0.534R. Since the actuator moves radially, the theoretical direction of motion at each point is also radial, without considering other influencing factors.

[0055] As one implementation, the radial extension range of the actuator tip (-ε1, ε1) is defined as (-0.6, 0.6), and the radial displacement of the actuator tip in the reference state is set to 0. Therefore, the ideal parabolic surface is z = 0.00177(x 2 +y 2 -299.9405.

[0056] Step 103: To verify the feasibility of the obtained parabola, it is necessary to ensure a smooth transition between the parabola and the reference sphere. A smooth transition can be considered as the obtained ideal parabola and the reference sphere smoothly connecting at a diameter R = 300 meters. The concept of curvature is used to analyze the smooth transition. The curvature calculation formula is as follows: Where s is the arc length of a fixed point on the curve, and γ is the tangential angle. When the curvature of the ideal parabola is very close to that of the reference sphere, it can be considered that the ideal parabola can smoothly transition to the reference sphere.

[0057] Table 1 Smoothness test results

[0058] Curvature of the reference sphere at the aperture The curvature of an ideal parabola at its edge Radial expansion of the edge 0.5744 0.5299 -0.3437

[0059] As shown in Table 1, the test results show that the curvature of the reference sphere and the ideal parabola at the aperture is very close. According to the calculation, the radial expansion and contraction of the edge main cable point is within the adjustable range. Therefore, the ideal parabola is feasible.

[0060] Step 2: When the celestial body S under test is in any position, obtain the coordinates of each node in the original coordinate system as well as the azimuth and elevation angles of the celestial body under test. Rotate the celestial body under test to be directly above the reference sphere through rotation transformation to obtain the position coordinates of each node in the new coordinate system. Figure 1The rotation process is demonstrated. The specific steps for obtaining the coordinates of each node in the new coordinate system through rotation transformation are as follows: Based on the azimuth and elevation angles of the measured celestial body S in the original coordinate system, calculate the transformation matrix; based on the transformation matrix, use the transformation formula to perform a rotation transformation on the coordinates of each node in the original coordinate system to obtain the coordinates of each node in the new coordinate system.

[0061] Let the azimuth angle of celestial body S in the original coordinate system be α and its elevation angle be β. Let (x',y',z')' be the coordinates of the point after the coordinate system rotation, and (x,y,z)' be the coordinates of the corresponding point in the original coordinate system. The transformation formula from the original coordinate system to the new coordinate system is:

[0062]

[0063] in,

[0064] Assuming the position of the celestial body being measured is α = 36.795° and β = 78.169°, the transformation matrix can be obtained.

[0065]

[0066] After transforming the coordinates, the coordinates of the vertex of the ideal parabola in the original coordinate system are (-48.6555, -36.9064, -294.2884).

[0067] Step 3: Calculate the center of the ideal parabolic aperture and, in conjunction with the radius of the reference sphere, determine the main cable node (the node to be adjusted) that needs to be moved.

[0068] Step 301: Let the center of the aperture of the ideal parabola be o'(x o' ,y o' ,z o' Through the above transformation, the coordinates of o′ can be obtained. With point o′ as the center, a sphere with the radius R of the reference sphere as its diameter is established, and the equation of the sphere is obtained:

[0069]

[0070] Step 302: The principal cable nodes that need to be moved must be inside the resulting sphere. The positions of these principal cable nodes must satisfy the condition that the distance to the center o′ of the sphere is less than the radius of the sphere, i.e., the coordinates of the principal cable nodes (x, y, y) must be within the sphere. i ,y i ,z i ), i = 1, ..., n, must satisfy the formula:

[0071]

[0072] According to formula (4), the set of main cable nodes I that need to be adjusted can be obtained.

[0073] Step 303: Find the equations of the lines l in the radial direction between all principal cable nodes and the center of the sphere in set I. i , i = 1, ..., n.

[0074]

[0075] Step 304: Combine equation (5) with equation (1) to form the ideal parabolic surface rotated, and combine with equation (3) to determine the coordinates Q of each main cable node. i (x i ,y i ,z i ), i = 1, ..., n.

[0076] As one implementation method, there are a total of 2226 main cable nodes for the active reflector. After screening, there are 580 nodes that actually fall in the reflector with a diameter of R=300 meters. Table 2 shows some of the node numbers.

[0077] Step 4: Establish a nonlinear target programming model. With the goal of minimizing the sum of the squares of the distances between the coordinates of all nodes that need to be moved in the radial direction between the working parabolic surface and the ideal parabolic surface, determine the target coordinates of all nodes that need to be moved and determine the working parabolic surface.

[0078] A nonlinear objective programming model is established with the objective function of minimizing the sum of the squares of the radial distances between the working parabolic surface and the ideal parabolic surface, and with the constraint that the range of the radial extension / retraction of the actuator is (-ε1, ε1) and the distance variation between adjacent nodes does not exceed ε2. This yields the position coordinates within the R-diameter of the adjusted reflector and the extension / retraction of each actuator. Let... Representing point Q i (x i ,y i ,z i The scaled coordinates are the target coordinates. When Q... i With Q j When adjacent, q ij =1, otherwise q ij =0, i,j=1,…,n. Let d(Q) i Q j ) for Q i With Q j The distance between them. For cross-sections of radio telescopes and the states of ideal and working parabolic surfaces, please refer to... Figure 2 .

[0079] The optimization model is established as follows:

[0080]

[0081] In one implementation, the distance variation between adjacent nodes is ε2 = 0.0007.

[0082] Step 5: Calculate the extension / retraction amount at the top of the actuator based on the position coordinates and target coordinates of all nodes that need to be moved.

[0083] By performing steps 3 and 4 of this invention, the nodes that need adjustment can be selected, and the corresponding node coordinates after adjustment can be provided. Table 2 shows some of the node numbers that need adjustment and their coordinates after adjustment, and Table 3 lists the extension and retraction of the actuator tip.

[0084] Table 2. Adjusted Main Cable Node Numbers and Coordinates

[0085]

[0086]

[0087] Table 3 Actuator tip extension / retraction amount

[0088]

[0089]

[0090] Step 6: Distribute the extension and retraction of each actuator tip to the corresponding node controller in the form of control commands. The actuator that receives the control command controls the motor to rotate according to the control command, thereby changing the length of the pull cable, forcing the connected node positions to change. The changes in the positions of multiple nodes ultimately change the shape of the active reflector.

[0091] Step 7: Based on the reflector adjustment method in Steps 1-6, the shape of the active reflector is changed. After the shape of the active reflector is changed, the receiver ratio of the feed cabin after adjustment is calculated to monitor the reception effect after the change in the shape of the active reflector. That is, the ratio of the reflected signal received by the effective area of ​​the feed cabin to the reflected signal of the reflector within a 300-meter aperture, and compared with the receiver ratio of the reference reflector spherical surface, thereby monitoring the reception effect after adjustment. For simplicity, a random reflector panel is taken as the research object to illustrate the calculation process of the receiver ratio.

[0092] (1) Calculate the normal vector of each reflective panel.

[0093] Choose any reflector panel The coordinates of the three main cable nodes on this panel are denoted as follows: calculate and The outer product of is used to obtain the normal vector of the reflective panel, and the unit normal vector of this normal vector is denoted as .

[0094] (2) Find the point where the reflected ray intersects with the plane containing the effective area of ​​the feed cabin.

[0095] The light emitted by the observed celestial body S is a parallel ray. By taking any point on the reflector panel and determining the reflected ray based on the incident ray and the normal vector, the equation of the reflected ray can be combined with the equation of the plane in which the effective area of ​​the feed cabin is located to obtain the intersection point of the reflected ray and the plane.

[0096] (3) The ratio of the reflected signal received in the effective area of ​​the feed cabin to the reflected signal from the reflective surface inside the aperture.

[0097] Each reflector panel has three reflection points corresponding to its vertex on the plane containing the feed cabin's circular surface. These three reflection points define a mapping triangle. The area of ​​the intersection between the mapping triangle and the feed cabin's circular surface is calculated, and this area is compared to the area of ​​the mapping triangle itself. The sum of these ratios for all reflector panels yields the reception ratio. The intersection of the mapping triangle and the feed cabin's circular surface can be found in [reference needed]. Figure 3 .

[0098] Based on the steps of the receiver ratio calculation, the adjusted receiver ratio of the working parabolic surface is approximately 77.8%, while the receiver ratio of the reference spherical surface is approximately 5.6%. This shows that the adjustment method provided by the present invention has a better receiver performance.

[0099] Radio telescopes conduct astronomical research by collecting radiation from celestial bodies in the universe and processing it into information that can be recorded and displayed. Since electromagnetic waves from celestial bodies are often extremely weak, to achieve better signal reception, this invention, under the constraint of adjusting the reflector panel, first determines the ideal parabolic surface corresponding to the observed celestial body directly above the reference sphere. Then, for celestial bodies in arbitrary positions, a rotational transformation is performed to adjust the coordinate system and determine the ideal parabolic surface after the rotation. To maximize the reception of signals emitted by the celestial body, the radial extension of the actuator is adjusted to adjust the reflector surface into a working parabolic surface, making this working parabolic surface as close as possible to the ideal parabolic surface to obtain the best reception effect after the electromagnetic waves from the celestial body are reflected by the reflector surface. During the adjustment process, a nonlinear optimization method is used to determine the corresponding nodes after the main cable node adjustment, and the intersection area of ​​the mapped triangle and the effective area of ​​the feed cabin is calculated. The reception ratio reflects the effectiveness of the working parabolic surface adjustment. The ratio of the reflected signal received by the effective area of ​​the feed cabin to the reflected signal of the 300-meter aperture reflector surface is calculated and compared with the reception ratio of the reference reflector sphere, verifying the effectiveness of the active reflector surface shape adjustment method.

[0100] Example 2

[0101] This embodiment provides a spherical radio telescope active reflector shape adjustment system, which specifically includes the following modules:

[0102] The ideal parabolic surface determination module is configured to: obtain the radius and focal diameter ratio of the reference sphere, update the coordinate system, and determine the ideal parabolic surface of the observed celestial body;

[0103] The rotation transformation module is configured to: obtain the coordinates of each node in the original coordinate system and the azimuth and elevation angles of the celestial body being measured, and obtain the position coordinates of each node in the new coordinate system through rotation transformation;

[0104] The module for determining the node to be adjusted is configured to: calculate the center of the ideal parabolic aperture and, in conjunction with the radius of the reference sphere, determine the node to be adjusted;

[0105] The target coordinate determination module is configured to determine the target coordinates of all nodes to be adjusted by minimizing the sum of the squares of the distances between the coordinates of all nodes to be adjusted in the radial direction between the working parabolic surface and the ideal parabolic surface.

[0106] The actuator tip extension / retraction calculation module is configured to calculate the actuator tip extension / retraction based on the position coordinates and target coordinates of all nodes to be adjusted.

[0107] After obtaining the actuator tip extension / retraction amount, the actuator tip extension / retraction amount calculation module distributes the extension / retraction amount of each actuator tip to the corresponding node controller in the form of control commands.

[0108] The node controller is configured to control the rotation of the motor according to control commands, thereby changing the length of the pull cable, forcing the position of the connected nodes to change, and ultimately changing the shape of the active reflector.

[0109] The monitoring module is configured to: calculate the receiver ratio of the feed cabin and monitor the reception effect after the shape of the active reflector changes; the receiver ratio of the feed cabin is the ratio of the reflected signal received in the effective area of ​​the feed cabin to the reflected signal of the reflector within the aperture.

[0110] It should be noted that each module in this embodiment corresponds one-to-one with each step in Embodiment 1, and their specific implementation processes are the same, so they will not be repeated here.

[0111] Example 3

[0112] This embodiment provides a computer-readable storage medium storing a computer program that, when executed by a processor, implements the steps in the method for adjusting the shape of the active reflector surface of a spherical radio telescope as described in Embodiment 1 above.

[0113] Example 4

[0114] This embodiment provides a computer device, including a memory, a processor, and a computer program stored in the memory and executable on the processor. When the processor executes the program, it implements the steps in the method for adjusting the shape of the active reflector surface of a spherical radio telescope as described in Embodiment 1 above.

[0115] Those skilled in the art will understand that embodiments of the present invention can be provided as methods, systems, or computer program products. Therefore, the present invention can take the form of hardware embodiments, software embodiments, or embodiments combining software and hardware aspects. Furthermore, the present invention can take the form of a computer program product embodied on one or more computer-usable storage media (including, but not limited to, disk storage and optical storage) containing computer-usable program code.

[0116] This invention is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of the invention. It will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, generate instructions for implementing the flowchart illustrations and / or block diagrams. Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.

[0117] These computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing device to function in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means, which are implemented in a process Figure 1 One or more processes and / or boxes Figure 1 The function specified in one or more boxes.

[0118] These computer program instructions may also be loaded onto a computer or other programmable data processing equipment to cause a series of operational steps to be performed on the computer or other programmable equipment to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable equipment for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 The steps of the function specified in one or more boxes.

[0119] Those skilled in the art will understand that all or part of the processes in the above embodiments can be implemented by a computer program instructing related hardware. The program can be stored in a computer-readable storage medium, and when executed, it can include the processes of the embodiments of the above methods. The storage medium can be a magnetic disk, optical disk, read-only memory (ROM), or random access memory (RAM), etc.

[0120] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A method for adjusting the shape of an active reflector of a spherical radio telescope, characterized in that, The method comprises the following steps: obtaining a reference spherical radius and a focal ratio, updating a coordinate system, and determining an ideal paraboloid of an observed celestial body; obtaining coordinates of each node in an original coordinate system and an azimuth and an elevation angle of the observed celestial body, and obtaining position coordinates of each node in a new coordinate system through rotation transformation; calculating a center of a caliber of the ideal paraboloid, and determining a node to be adjusted in combination with the reference spherical radius; determining target coordinates of all the nodes to be adjusted in a manner that a sum of squares of distances between coordinates of all the nodes to be adjusted in a radial direction of a working paraboloid and the ideal paraboloid is minimum; calculating an extension amount of a top end of an actuator based on the position coordinates and the target coordinates of all the nodes to be adjusted; wherein the specific steps of obtaining the position coordinates of each node in the new coordinate system through rotation transformation are as follows: calculating a transformation matrix based on the azimuth and the elevation angle of the observed celestial body in the original coordinate system; performing rotation transformation on the coordinates of each node in the original coordinate system based on the transformation matrix to obtain the coordinates of each node in the new coordinate system; wherein the specific steps of determining the node to be adjusted are as follows: establishing a spherical surface with the center of the caliber of the ideal paraboloid as a spherical center and with the reference spherical radius as a diameter, obtaining a spherical surface equation, and obtaining a set of the nodes to be adjusted; obtaining a straight line equation of each node in the set and a radial direction of the spherical center; combining the straight line equation with the ideal paraboloid, and determining the position coordinates of each node to be adjusted in combination with the spherical surface equation.

2. The method for adjusting the shape of the active reflecting surface of a spherical radio telescope as described in claim 1, characterized in that, The specific method of updating the coordinate system is to take a line connecting the observed celestial body and the spherical center of the reference spherical surface as a Z axis, to determine an X axis and a Y axis according to a right-hand rule, and to re-establish a new coordinate system.

3. A method of adjusting the shape of an active reflector surface of a spherical radio telescope according to claim 2, characterized in that, The receiving ratio of the feed cabin is a ratio of a reflected signal received by an effective area of the feed cabin to a reflected signal of the caliber inner reflecting surface.

4. A spherical radio telescope active reflector surface shape adjustment system, characterized by, The method comprises the following steps: an ideal paraboloid determination module configured to obtain a reference spherical radius and a focal ratio, update a coordinate system, and determine an ideal paraboloid of an observed celestial body; a rotation transformation module configured to obtain coordinates of each node in an original coordinate system and an azimuth and an elevation angle of the observed celestial body, and obtain position coordinates of each node in a new coordinate system through rotation transformation; a node to be adjusted determination module configured to calculate a center of a caliber of the ideal paraboloid, and determine a node to be adjusted in combination with the reference spherical radius; a target coordinate determination module configured to determine target coordinates of all the nodes to be adjusted in a manner that a sum of squares of distances between coordinates of all the nodes to be adjusted in a radial direction of a working paraboloid and the ideal paraboloid is minimum; an actuator top end extension amount calculation module configured to calculate an extension amount of a top end of an actuator based on the position coordinates and the target coordinates of all the nodes to be adjusted; wherein the specific steps of obtaining the position coordinates of each node in the new coordinate system through rotation transformation are as follows: calculating a transformation matrix based on the azimuth and the elevation angle of the observed celestial body in the original coordinate system; performing rotation transformation on the coordinates of each node in the original coordinate system based on the transformation matrix to obtain the coordinates of each node in the new coordinate system; wherein the specific steps of determining the node to be adjusted are as follows: A spherical surface with a diameter of the reference spherical radius is established with the center of the ideal parabolic aperture as the center of the sphere, a spherical surface equation is obtained, and a set of nodes to be adjusted is obtained; A straight line equation of all nodes in the set and the radial direction of the center of the sphere is obtained; The straight line equation and the ideal parabolic surface are combined, and the position coordinates of each node to be adjusted are determined in combination with the spherical surface equation.

5. A spherical radio telescope active reflector shape adjusting system as claimed in claim 4, characterized in that, The actuator tip telescopic amount calculation module obtains the actuator tip telescopic amount, and distributes each actuator tip telescopic amount to the corresponding node controller in the form of a control instruction; The node controller controls the motor to rotate according to the control instruction, changes the length of the pull-down cable, forces the connected node position to change, multiple node positions to change, and finally changes the shape of the active reflector.

6. A spherical radio telescope active reflector shape adjusting system as claimed in claim 4, characterized in that, Further comprising a monitoring module configured to: calculate the receiving ratio of the feed cabin, and monitor the receiving effect after the shape of the active reflector is changed; the receiving ratio of the feed cabin is the ratio of the reflected signal received by the effective area of the feed cabin to the reflected signal of the aperture inner reflector.

7. A computer-readable storage medium having stored thereon a computer program, characterized in that, The program is executed by the processor to implement the steps in the method for adjusting the shape of the active reflector of the spherical radio telescope according to any one of claims 1-3.

8. A computer device comprising a memory, a processor, and a computer program stored on the memory and executable on the processor, characterized in that, The processor executes the program to implement the steps in the method for adjusting the shape of the active reflector of the spherical radio telescope according to any one of claims 1-3.

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