A method for establishing a surface measurement reference point based on the CAD surface type conversion method

Abstract

The present invention proposes a method for establishing a curved surface measurement reference point based on the CAD surface type conversion method. Before the installation of the sub-reflector, discrete points on the side of the sub-reflector, curved surface discrete points, and measurement reference points are collected on the ground. Through the CAD surface type conversion method, matching and iterative calculations are performed with the theoretical mathematical model in the global coordinate system O-XYZ to obtain the coordinate values of the measurement reference points fixed at the four corners of the sub-reflector in the global coordinate system O-XYZ as the theoretical coordinate values. After the installation of the sub-reflector is completed, the measured coordinate values of the measurement reference points at the four corners of the sub-reflector are measured in the global coordinate system O-XYZ and compared with their theoretical coordinate values. The deviation value between the measured coordinate value and the theoretical coordinate value is the measurement adjustment accuracy of the three-dimensional space absolute position and attitude of the sub-reflector. After multiple measurements and adjustments, the accuracy of the three-dimensional space absolute position and attitude of the sub-reflector is better than 1 mm, and the index requirements are met when the dual-focus reflector multi-beam reflector antenna system receives the corresponding satellite electromagnetic wave level value.

Description

Technical Field

[0001] The present invention relates to the field of installation, measurement, and adjustment of industrial equipment, and specifically to a method for establishing a curved surface measurement reference point based on the CAD surface type conversion method. Background Technique

[0002] With the rapid development of industrial technology and materials science, the raw materials for industrial equipment are no longer limited to metal materials. In particular, composite materials such as carbon fiber and glass fiber reinforced plastics are widely used in various industrial fields. Especially in the antenna field, more and more high-performance antenna reflectors are made of carbon fiber, or a method of using glass fiber reinforced plastics with a metal coating is selected based on weather resistance considerations.

[0003] During the installation and operation stages of antenna equipment, the measurement and adjustment of the absolute position and attitude of the sub-reflector in space require the pre-processing of measurement reference points on the sub-reflector. However, composite materials do not have the good machinability of metal materials. For sub-reflectors made of carbon fiber or other non-metal materials, the processing of measurement reference points is difficult and costly. In addition, for ultra-large aperture antennas, such as the QTT 110m radio telescope, its sub-reflector is a 12m aperture "antenna" composed of multiple single panels spliced together. Therefore, it is difficult to pre-process measurement reference points for accurately measuring and adjusting the sub-reflector. Summary of the Invention

[0004] In order to solve the problem that it is difficult to pre-process measurement reference points for measuring and adjusting the three-dimensional space absolute position and attitude of the sub-reflector of a carbon fiber sub-reflector or a sub-reflector composed of multiple single panels spliced together, the present invention proposes a method for establishing a curved surface measurement reference point based on the CAD surface type conversion method. Based on the CAD surface type conversion, after the processing or splicing of the sub-reflector is completed, measurement reference points are established for measuring and adjusting the three-dimensional space absolute position and attitude of the sub-reflector, and it has been successfully applied in a certain dual-focus reflector multi-beam antenna project.

[0005] The basic principle of the present invention is:

[0006] Before the sub-reflector is installed, a laser tracker measurement system is used on the ground to collect discrete points on the side of the sub-reflector, discrete points on the curved surface, and measurement reference points. Through the CAD surface type conversion method, matching and iterative calculations are carried out with the corresponding theoretical mathematical model of the sub-reflector in the global coordinate system O-XYZ, and the coordinate values of the circular tooling (measurement reference points) made of plastic material fixed at the four corners of each sub-reflector in the global coordinate system O-XYZ are obtained, that is, the theoretical coordinate values of the sub-reflector measurement reference points in the global coordinate system. After the sub-reflector is installed, a total station measurement system or a laser tracker measurement system is used to measure the actual coordinate values of the measurement reference points at the four corners of the aforementioned sub-reflector in the global coordinate system O-XYZ, and compare them with their theoretical coordinate values. The deviation value between the actual coordinate value and the theoretical coordinate value is the measurement and adjustment accuracy of the three-dimensional space absolute position and attitude of the sub-reflector. After multiple measurements and adjustments, the accuracy of the three-dimensional space absolute position and attitude of the sub-reflector is better than 1 mm, and the index requirements are met when the dual-focus reflector multi-beam reflector antenna system receives the corresponding satellite electromagnetic wave level value.

[0007] The technical solution of the present invention is as follows:

[0008] A method for establishing a curved surface measurement reference point based on the CAD surface type conversion method, comprising the following steps:

[0009] Step 1: For a certain sub-reflector of the antenna system, three groups of discrete point sets are measured on the ground by an industrial measurement system. The three groups of discrete point sets are respectively the side discrete point set on the side of the sub-reflector, the curved surface discrete point set on the front of the sub-reflector, and the measurement reference point set arranged at the four corners on the front of the sub-reflector;

[0010] Step 2: In a three-dimensional space analysis software, import the theoretical mathematical model of the sub-reflector in the global coordinate system, and import the side discrete point set, the curved surface discrete point set, and the measurement reference point set obtained in Step 1 into the three-dimensional space analysis software, and obtain the coordinate values of the measurement reference points in the global coordinate system O-XYZ based on the CAD surface type conversion method:

[0011] Step 2.1: In a three-dimensional space analysis software, import the theoretical mathematical model of the sub-reflector in the global coordinate system;

[0012] Step 2.2: Import the side discrete point set, the curved surface discrete point set, and the measurement reference point set obtained in Step 1 into the three-dimensional space analysis software;

[0013] Step 2.3: Rotate and move the side discrete point set, the curved surface discrete point set, and the measurement reference point set to roughly align the side discrete point set, the curved surface discrete point set, and the measurement reference point set with the corresponding sides and the front of the theoretical mathematical model of the sub-reflector;

[0014] Step 2.4: Select the side discrete point set, perform matching calculations with the theoretical mathematical model of the sub-reflector, obtain the transformation matrix between the side discrete point set and the theoretical mathematical model of the sub-reflector, and transform the side discrete point set. During this process, the surface discrete point set and the measurement reference point set do not participate in the matching calculations, but are transformed according to the transformation matrix obtained from the calculation results of the side discrete point set;

[0015] Step 2.5: Select the surface discrete point set, perform matching calculations with the theoretical mathematical model of the sub-reflector, obtain the transformation matrix between the surface discrete point set and the theoretical mathematical model of the sub-reflector, and transform the surface discrete point set. During this process, the measurement reference point set does not participate in the matching calculations, but is further transformed according to the transformation matrix obtained from the calculation results of the surface discrete point set to obtain the coordinate values of the measurement reference points in the global coordinate system O-XYZ;

[0016] Step 3: According to the coordinate values of the measurement reference points in the global coordinate system O-XYZ obtained in Step 2, use them as the theoretical reference values for the three-dimensional spatial absolute position and attitude of the sub-reflector in the industrial equipment system; after the sub-reflector is actually installed, use an industrial measurement system to measure the actual coordinate values of the measurement reference points on the sub-reflector in the global coordinate system O-XYZ, and compare and adjust them with the theoretical reference values to make the actual position and attitude of the sub-reflector approach the theoretical three-dimensional spatial absolute position and attitude.

[0017] Further, the industrial measurement system uses a digital industrial photogrammetry system, a coordinate measuring system, a laser tracker measuring system, or a three-dimensional scanner measuring system.

[0018] Further, the measurement reference points are fixed at the four corner positions on the front of the sub-reflector in a non-destructive manner.

[0019] Further, the three-dimensional spatial analysis software uses Spatial Analyzer. In the Spatial Analyzer software, create an SA project, and import the theoretical mathematical model of the sub-reflector in the global coordinate system, as well as the side discrete point set, the surface discrete point set, and the measurement reference point set.

[0020] Further, in Step 2.4 and Step 2.5, the command "Relationship Matching - Point to Object - Minimize Movement of Object through Relationship" is applied in the SA software to select the corresponding side discrete point set or surface discrete point set for matching calculations with the theoretical mathematical model of the sub-reflector.

[0021] Beneficial effects

[0022] A method for establishing a curved surface measurement reference point based on the CAD surface type conversion method proposed by the present invention effectively provides a method for processing curved surfaces made of composite materials such as carbon fiber and glass fiber reinforced plastics without pre-processing measurement reference points. At the same time, it also effectively solves the problem of the curved surface measurement reference point during installation, measurement, and adjustment of the curved surface, reduces the difficulty of processing and manufacturing, and reduces the processing and manufacturing cost. At the same time, it provides an effective solution for the fixed measurement reference points required for the measurement and adjustment of the absolute position and attitude of the three-dimensional space of the curved surface composed of multiple single curved surfaces.

[0023] Additional aspects and advantages of the present invention will be given in part in the following description, become apparent in part from the following description, or be learned through the practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] The above and / or additional aspects and advantages of the present invention will become apparent and be readily understood from the description of the embodiments in conjunction with the following drawings, in which:

[0025] Figure 1 : Schematic diagram of the absolute position and attitude of the three-dimensional space of the curved surface;

[0026] Figure 2 : Schematic diagram of the steps for obtaining the theoretical coordinate values of the global coordinate system of the curved surface measurement reference point;

[0027] Figure 3 : Schematic diagram of the distribution of discrete points and measurement reference points on the curved surface;

[0028] Figure 4 : Schematic diagram of a dual-focus reflector multi-beam antenna;

[0029] Figure 5 : Schematic diagram of the laser tracker measurement system for collecting discrete points and measurement reference points of the sub-reflector on the ground;

[0030] Figure 6 : Schematic diagram of the distribution of measurement reference points on the sub-reflector and a plastic circular tooling;

[0031] Figure 7 : Schematic diagram of importing the theoretical mathematical model of the sub-reflector in the global coordinate system into the SA project in the three-dimensional space analysis software Spatial Analyzer;

[0032] Figure 8 : Schematic diagram of importing the collected boundary point set, discrete point set, and measurement reference point set of the sub-reflector into the SA project;

[0033] Figure 9 : Schematic diagram of manually moving and rotating the discrete point set and the measurement reference point set to be roughly aligned with the theoretical mathematical model, and the result of the first CAD surface type conversion using the boundary discrete point set of the sub-reflector and the theoretical mathematical model;

[0034] Figure 10 : Schematic diagram of the matching calculation result of the CAD surface type conversion method between the discrete point set of the surface of the sub-reflector and the theoretical mathematical model of the sub-reflector, and the result of obtaining the theoretical coordinate values of the global coordinate system of the measurement reference points of the sub-reflector;

[0035] Figure 11 : Schematic diagram of the actual coordinate values of the measurement reference points of the sub-reflector with known theoretical coordinate values of the global coordinate system measured by the total station measurement system in the global coordinate system;

[0036] Figure 12 : Schematic diagram of the results of multiple measurements and adjustments of the absolute position and attitude of the sub-reflector in three-dimensional space;

[0037] Figure 13 : Schematic diagram of the received satellite electromagnetic wave level value during the satellite pointing test after adjustment. Detailed implementation manners

[0038] The embodiments of the present invention will be described in detail below. The embodiments are exemplary and are intended to explain the present invention, but should not be construed as limiting the present invention.

[0039] In the description of the present invention, it should be understood that the orientation or positional relationship indicated by the terms "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", etc. is based on the orientation or positional relationship shown in the drawings, and is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be construed as limiting the present invention.

[0040] In addition, the terms "first" and "second" are only used for descriptive purposes and should not be construed as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined with "first" and "second" may explicitly or implicitly include one or more of such features. In the description of the present invention, "a plurality" means two or more unless otherwise specifically defined.

[0041] In this embodiment, the absolute position and attitude of the sub-reflector of a certain dual-focus reflector multi-beam antenna system are measured and adjusted during the installation stage.

[0042] A certain dual-focus reflector multi-beam antenna system consists of 1 set of antenna main reflectors and 8 sets of feed systems. The main beam direction of the antenna main reflector is fixed and unique. Each set of feed systems includes 1 set of feeds and 1 set of sub-reflectors installed on the test bench, asFigure 4 As shown in the figure. To ensure that the index of the received satellite electromagnetic wave level value of the antenna system meets the requirements, it is necessary to accurately measure and adjust the three-dimensional spatial position and attitude of 8 sub-reflectors in the global coordinate system O-XYZ. Therefore, "measurement reference points" should be reserved on the sub-reflectors before installation. Since the sub-reflectors of this antenna system are made of carbon fiber, it is not easy to pre-process measurement holes as measurement reference points during the processing stage. For this reason, this embodiment adopts a method of establishing a curved surface measurement reference point based on the CAD surface type conversion method to realize the measurement and adjustment of the three-dimensional spatial absolute position and attitude of the sub-reflector. The main idea is as follows:

[0043] Perform CAD surface type conversion on 8 sub-reflectors of a certain dual-focus reflector multi-beam antenna system on the ground to obtain the coordinate values of the measurement reference points in the global coordinate system O-XYZ. Then, install the sub-reflector on the feeder system bracket of the test tower, and use a total station measurement system to measure the actual coordinate values of the measurement reference points of the sub-reflector in the global coordinate system O-XYZ, and compare them with the theoretical coordinate values of the measurement reference points obtained by the CAD surface type conversion method. After multiple measurements and adjustments, the accuracy of the three-dimensional spatial absolute position and attitude of the sub-reflector is better than 1.5 mm, and the index requirements are met when the dual-focus reflector multi-beam reflector antenna system receives the corresponding satellite electromagnetic wave level value.

[0044] Specifically, it includes the following steps:

[0045] Step 1: For a certain sub-reflector, use an industrial measurement system on the ground to measure three groups of discrete point sets. The three groups of discrete point sets are the side discrete point set on the side of the sub-reflector, the curved surface discrete point set on the front of the sub-reflector, and the measurement reference point set arranged at the four corners on the front of the sub-reflector.

[0046] When measuring, industrial measurement systems such as digital industrial photogrammetry systems, coordinate measuring systems, laser tracker measurement systems, and 3D scanner measurement systems can be selected; in this embodiment, the side discrete point set is collected at intervals of 100 mm in the arc length direction; the curved surface discrete point set is collected in the form of "row × column", and the row and column intervals are 100 mm; a plastic circular tooling is fixed at the four corners on the front of the sub-reflector by non-destructive methods such as gluing as the measurement reference point, such as Figure 3 , Figure 5 and Figure 6 shown. When the plastic circular tooling is pasted on the front of the sub-reflector, it only needs to be roughly at the four corners, and precise positioning is not required, so precise processing is not needed.

[0047] Step 2: In the 3D space analysis software, import the theoretical mathematical model of the sub-reflector under the global coordinate system, and import the side discrete point set, surface discrete point set, and measurement reference point set obtained in Step 1 into the 3D space analysis software. Based on the CAD surface type conversion method, obtain the coordinate values of the measurement reference points under the global coordinate system O-XYZ.

[0048] The CAD surface type conversion method directly converts the measured discrete points and the theoretical CAD surface. Its essence is "surface fitting with boundary conditions". The conversion principle is as follows: The initial value of the coordinate conversion is adjusted manually by the CAD surface type and the measured data to make them roughly coincide, and the approximate coordinate conversion parameters are determined. Then, the 3D space analysis software program performs fitting calculations according to the approximate coordinate conversion parameters according to the least square principle until the sum of the squares of the distances from all discrete points to the theoretical mathematical model of the surface is minimized and the calculation stops. At this time, the normal deviation of the measured surface type relative to the CAD surface type can be obtained, and the coordinate values of the measurement reference points under the global coordinate system of the theoretical mathematical model of the surface can also be obtained.

[0049] The specific process of Step 2 is as follows:

[0050] Step 2.1: In the 3D space analysis software, import the theoretical mathematical model of the sub-reflector under the global coordinate system; in this embodiment, use the 3D space analysis software Spatial Analyzer to create a new SA project and import the theoretical mathematical model of the sub-reflector under the global coordinate system. At this time, the SA project coordinate system is the global coordinate system, as Figure 7 shown.

[0051] Step 2.2: Import the side discrete point set, surface discrete point set, and measurement reference point set obtained in Step 1 into the SA project.

[0052] Step 2.3: In the SA project, manually rotate and move the side discrete point set, surface discrete point set, and measurement reference point set to roughly align the side discrete point set, surface discrete point set, and measurement reference point set with the corresponding sides and the front of the theoretical mathematical model of the sub-reflector.

[0053] As Figure 8 shown, import the collected side discrete point set, surface discrete point set, and measurement reference point set into the SA project with the theoretical mathematical model of the sub-reflector loaded. Since the coordinate system in the SA project is the global coordinate system, while the coordinate systems of the side discrete point set, surface discrete point set, and measurement reference point set collected by the laser tracker (industrial measurement system) are the default global coordinate systems in the SA project, there is a deviation between the imported side discrete point set, surface discrete point set, and measurement reference point set and the theoretical mathematical model of the sub-reflector. It is necessary to manually rotate and move and then perform CAD surface type conversion to roughly align the side discrete point set, surface discrete point set, and measurement reference point set with the theoretical mathematical model of the sub-reflector.

[0054] Step 2.4: Select the side discrete point set, perform matching calculation with the sub-reflector theoretical mathematical model, obtain the conversion matrix between the side discrete point set and the sub-reflector theoretical mathematical model, and convert the side discrete point set. In this process, the surface discrete point set and the measurement reference point set do not participate in the matching calculation, but are converted according to the conversion matrix obtained by the calculation result of the side discrete point set. Specifically in this embodiment, the "Relationship Matching-Point to Object-Minimize Moving Objects by Relationship" command is applied in the SA software to select the side discrete point set and the sub-reflector theoretical mathematical model for matching calculation.

[0055] like Figure 9 As shown, after manually moving and rotating the side discrete point set, the surface discrete point set and the measurement reference point set to align with the theoretical mathematical model of the sub-reflector, the side discrete point set and the theoretical mathematical model of the sub-reflector are used to perform the first CAD surface conversion. After calculation and conversion, the side discrete point set, the surface discrete point set and the measurement reference point set basically fit the theoretical mathematical model. However, due to the relatively low processing accuracy of the side boundary of the sub-reflector, the calculation results are not sufficient to obtain the theoretical coordinate values ​​of the measurement reference points in the global coordinate system.

[0056] Step 2.5: Select the surface discrete point set, perform matching calculation with the sub-reflector theoretical mathematical model, obtain the conversion matrix between the surface discrete point set and the sub-reflector theoretical mathematical model, and convert the surface discrete point set. In this process, the measurement reference point set does not participate in the matching calculation, but is further converted according to the conversion matrix obtained from the calculation result of the surface discrete point set. Specifically in this embodiment, the "Relationship Matching—Point to Object—Minimize Moving Objects by Relationship" command is also applied in the SA software to select the surface discrete point set and the sub-reflector theoretical mathematical model for matching calculation. At this time, the point position accuracy of the surface discrete point set relative to the sub-reflector theoretical mathematical model is the highest, and at this time it is the global coordinate system O-XYZ, and the coordinate value of the measurement reference point in the global coordinate system O-XYZ can be obtained.

[0057] like Figure 10 As shown, the CAD surface conversion method matching calculation is performed using the surface discrete point set and the theoretical mathematical model of the sub-reflector. After iterative calculation, the calculation is stopped until the sum of the squares of the surface discrete point set from the surface theoretical mathematical model is minimized. At this time, the normal deviation of the measured surface relative to the CAD surface can be obtained, and the high-precision coordinate value of the measurement reference point in the CAD surface global coordinate system can also be obtained, which can be used as the theoretical coordinate value for the measurement and adjustment of the absolute position and posture of the sub-reflector in three-dimensional space.

[0058] Step 3: Use the coordinate values of the measurement reference points obtained in Step 2 in the global coordinate system O-XYZ as the theoretical reference values for the three-dimensional spatial absolute position and attitude of the sub-reflector in the industrial equipment system. After the sub-reflector is actually installed, use an industrial measurement system to measure the actual coordinate values of the measurement reference points on the sub-reflector in the global coordinate system O-XYZ, and compare and adjust them with the theoretical reference values to make the actual position and attitude of the sub-reflector approach the theoretical three-dimensional spatial absolute position and attitude.

[0059] As Figure 11 - 12 shown, after the sub-reflector is installed on the feed system bracket, taking the No. 1 sub-reflector as an example, use a total station measurement system to measure the actual coordinate values of the measurement reference points of the sub-reflector with known theoretical coordinate values in the global coordinate system, and compare them with the theoretical coordinate values. After multiple measurements, the accuracy of the three-dimensional spatial absolute position and attitude of the sub-reflector is better than 1.5 mm.

[0060] As Figure 13 shown, taking the No. 1 sub-reflector as an example, based on the main reflector whose main beam pointing and surface accuracy measurement and adjustment have been completed, after the three-dimensional spatial absolute position and attitude measurement and adjustment of the sub-reflector are completed, conduct a satellite alignment test, and the received satellite electromagnetic wave level value meets the index requirements.

[0061] Although the embodiments of the present invention have been shown and described above, it can be understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Those of ordinary skill in the art can make changes, modifications, substitutions, and variations to the above embodiments within the scope of the present invention without departing from the principles and purposes of the present invention.

Claims

1. A method for establishing a curved surface measurement reference point based on a CAD surface conversion method, characterized in that: The following steps are involved: Step 1: For a certain sub-reflector of the antenna system, three sets of discrete point sets are measured on the ground using an industrial measurement system. The three sets of discrete point sets are the side discrete point set on the side of the sub-reflector, the curved surface discrete point set on the front of the sub-reflector, and the measurement reference point set arranged at the four corners of the front of the sub-reflector; Step 2: In the 3D space analysis software, import the theoretical mathematical model of the sub-reflector in the global coordinate system, and import the side discrete point set, surface discrete point set and measurement reference point set obtained in step 1 into the 3D space analysis software, and obtain the coordinate values ​​of the measurement reference points in the global coordinate system O-XYZ based on the CAD surface conversion method: Step 2.1: In the three-dimensional space analysis software, import the sub-reflector theoretical mathematical model in the global coordinate system; Step 2.2: Import the side discrete point set, surface discrete point set and measurement reference point set obtained in step 1 into the three-dimensional space analysis software; Step 2.3: Rotate and move the side discrete point set, the surface discrete point set and the measurement reference point set so that the side discrete point set, the surface discrete point set and the measurement reference point set are roughly aligned with the corresponding side and front of the sub-reflector theoretical mathematical model; Step 2.4: Select the side discrete point set, perform matching calculation with the sub-reflector theoretical mathematical model, obtain the conversion matrix between the side discrete point set and the sub-reflector theoretical mathematical model, and convert the side discrete point set. In this process, the surface discrete point set and the measurement reference point set do not participate in the matching calculation, but are converted according to the conversion matrix obtained by the calculation result of the side discrete point set; Step 2.5: Select a surface discrete point set, perform matching calculation with the sub-reflector theoretical mathematical model, obtain the conversion matrix between the surface discrete point set and the sub-reflector theoretical mathematical model, and convert the surface discrete point set. In this process, the measurement reference point set does not participate in the matching calculation, but is further converted according to the conversion matrix obtained by the calculation result of the surface discrete point set to obtain the coordinate value of the measurement reference point in the global coordinate system O-XYZ; Step 3: The coordinate value of the measurement reference point in the global coordinate system O-XYZ obtained in step 2 is used as the theoretical reference value of the three-dimensional space absolute position and posture of the sub-reflector in the industrial equipment system; after the sub-reflector is actually installed, the industrial measurement system is used to measure the actual coordinate value of the measurement reference point on the sub-reflector in the global coordinate system O-XYZ, and the actual coordinate value is compared and adjusted with the theoretical reference value to make the actual position and posture of the sub-reflector approach the theoretical three-dimensional space absolute position and posture.

2. The method for establishing a curved surface measurement reference point based on a CAD surface conversion method according to claim 1, characterized in that: The industrial measurement system adopts a digital industrial photography measurement system, a three-coordinate measurement system, a laser tracker measurement system or a three-dimensional scanner measurement system.

3. The method for establishing a curved surface measurement reference point based on a CAD surface conversion method according to claim 1, characterized in that: The measurement reference points are fixed at the four corners of the front side of the secondary reflector in a non-destructive manner.

4. The method for establishing curved surface measurement reference points based on CAD surface conversion method according to claim 1, characterized in that: The three-dimensional spatial analysis software adopts Spatial Analyzer. In the Spatial Analyzer software, an SA project is created, and a sub-reflector theoretical mathematical model in a global coordinate system, as well as a side discrete point set, a surface discrete point set, and a measurement reference point set are imported.

5. The method for establishing curved surface measurement reference points based on CAD surface conversion method according to claim 4, characterized in that: In steps 2.4 and 2.5, the "Relationship Matching—Point to Object—Minimize Moving Objects by Relationship" command is applied in the SA software to select the corresponding side discrete point set or surface discrete point set and the sub-reflector theoretical mathematical model for matching calculation.

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