Measurement method for the installation position of the end probe of the on-board drum-type extension rod mechanism

Abstract

This invention relates to a method for measuring the installation position of the end probe of a satellite-mounted retractable extension mechanism, comprising the following steps: Step 1: Before satellite installation, based on the measurement reference of the retractable extension mechanism, measure and obtain the dimensional range of the extended elongation and extension angle of the electric field detector probe; Step 2: Establish a satellite-wide coordinate system; Step 3: In the satellite-wide coordinate system, measure the measurement reference of the retractable extension mechanism, and fit the position of the origin of the retractable extension mechanism's extension direction on the satellite and the angle of the extension direction on the satellite; Step 4: Based on the dimensional range of the extended elongation and extension angle of the electric field detector probe, the position of the origin of the retractable extension mechanism's extension direction on the satellite, and the angle of the extension direction on the satellite, calculate the actual installation position relationship of the electric field detector probe on the satellite in the extended state. This invention achieves the position measurement of the satellite-mounted electric field detector probe with a relatively simple reference structure and measurement steps.

Description

Technical Field

[0001] This invention relates to the field of aerospace equipment technology, and in particular to a method for measuring the installation position of the end probe of an onboard reel-type extension rod mechanism. Background Technology

[0002] The electromagnetic monitoring test satellite is equipped with four tetrahedral spherical electric field detectors. It obtains the three-axis electric field in space by utilizing the relationship between the potential difference and distance between each pair of detectors. To minimize electromagnetic interference from the satellite itself, the four detectors need to be at least 4 meters away from the satellite's surface during on-orbit operation. Therefore, four sets of retractable extension rod mechanisms pointing in different directions are installed on the surface of the electromagnetic monitoring test satellite, with the four electric field detectors mounted at the ends of these mechanisms. During satellite launch, the retractable extension rod mechanisms are in a retracted state; after the satellite enters orbit, they extend and unfold along the axis of the retractable cylinders.

[0003] On the ground, it is necessary to measure the actual position information of four electric field detector probes in the deployed state of the roll-type extension mechanism to determine their spacing. The deployment principle and inherent structure of the roll-type extension mechanism determine that its extension amount and angle will have a certain random deviation each time, and only a specific range of accuracy can be given. Its design is suitable for microgravity deployment. It is not possible to deploy the four roll-type extension mechanisms in all directions on the satellite from the ground and directly measure the actual position of the four electric field detector probes. Only an indirect measurement method can be used, that is, to measure the positional relationship between the electric field detector probes and the roll-type extension mechanism in the single deployed state of the roll-type extension mechanism, and to measure the position and angle relationship between the roll-type extension mechanism and the satellite in the retracted state from the satellite. Therefore, it is necessary to establish a reference structure and measurement method on the roll-type extension mechanism and the satellite that can transmit measurement accuracy.

[0004] Satellites typically use reference mirrors to transmit angular relationships and pins or other reference features to transmit positional relationships. Both the satellite and the equipment under test require precise reference mirrors, pins and pin holes, or other reference features. Individual units also need pre-calibration, and sometimes even additional drilling templates are required to transmit angle and positional relationships. The drum-type extension rod mechanism, developed and applied for the first time in China, has a complex shape and is positioned on the surfaces of various side plates on the satellite, which are frequently disassembled and reassembled. Conventional measurement methods have not been adapted to the characteristics of the electromagnetic monitoring test satellite, making both the measurement reference structure and the measurement process overly complex. Currently, there is a lack of a matching reference structure and measurement method to transmit measurement accuracy. Summary of the Invention

[0005] The technical problem solved by this invention is to overcome the shortcomings of the prior art and provide a method for measuring the installation position of the end probe of a satellite-mounted drum-type extension rod mechanism. The method has high measurement accuracy, a simple measurement process, and is easy to operate.

[0006] The technical solution of this invention is: a method for measuring the installation position of the end probe of a satellite-mounted drum-type extension rod mechanism, characterized by including the following steps:

[0007] Step 1: Before satellite installation, based on the measurement reference of the drum-type extension rod mechanism, measure and obtain the dimensional range of the extended length and extension angle of the electric field detector probe.

[0008] Step 2: Establish the whole star coordinate system;

[0009] Step 3: In the whole satellite coordinate system, measure the measurement reference of the drum-type extension rod mechanism, and fit the position of the origin of the extension direction of the drum-type extension rod mechanism on the satellite and the angle of the extension rod extension direction on the satellite respectively;

[0010] Step 4: Based on the dimensional range of the extended elongation and extended angle of the electric field detector probe measured in Step 1, the position of the origin of the roll-type extension mechanism on the satellite and the angle of the extension direction on the satellite measured in Step 3, calculate the actual installation position relationship of the electric field detector probe on the satellite in the on-orbit extended state.

[0011] In the method for measuring the installation position of the end probe of the on-board reel-type extension rod mechanism, in step one, the outer surface of the elastic reel storage box and the mounting surface of the mounting base are used as the measurement reference for the reel-type extension rod mechanism.

[0012] In the method for measuring the installation position of the end probe of the on-board reel-type extension rod mechanism, the extension rod unfolding direction is taken as the direction of the central axis extending from the outer surface of the elastic reel storage box, and the intersection of the central axis and the mounting surface on the mounting base is the origin of the extension rod unfolding direction.

[0013] In the method for measuring the installation position of the end probe of the on-board reel-type extension rod mechanism, a first boss surface and a second boss surface are set on the Z-side of the satellite structure base plate; the first boss surface and the second boss surface are coplanar and both protrude outward from the outer surface of the satellite body on which they are located.

[0014] And / or on the negative Y side of the satellite structure base plate, a third protrusion and a fourth protrusion are provided; the third protrusion and the fourth protrusion are coplanar and both protrude outward from the outer surface of the satellite body on which they are located;

[0015] In step two, the first and second protruding surfaces or the third and fourth protruding surfaces are used as the position references for the entire star coordinate system.

[0016] In the method for measuring the installation position of the end probe of the on-board reel-type extension mechanism, the flatness of the first boss surface and the second boss surface is not greater than 0.05 mm; the flatness of the third boss surface and the fourth boss surface is not greater than 0.05 mm.

[0017] In the method for measuring the installation position of the end probe of the on-board reel-type extension mechanism, in step two, a position is selected where the first boss surface, the second boss surface, the satellite-rocket docking surface, the outer surface of the elastic reel storage box, and the mounting surface of the mounting base can be observed simultaneously, or the position of the third boss surface, the fourth boss surface, the satellite-rocket docking surface, the outer surface of the elastic reel storage box, and the mounting surface of the mounting base can be observed simultaneously. A laser tracker is used to measure and establish the whole satellite coordinate system.

[0018] In the method for measuring the installation position of the end probe of the on-board drum-type extension rod mechanism, the satellite docking ring's satellite-rocket docking surface is measured and fitted as the YOZ surface of the whole satellite coordinate system;

[0019] Measure and fit the lower outer circumferential surface of the satellite docking ring, and project the center of the lower outer circumferential surface of the satellite docking ring onto the satellite YOZ plane as the origin of the whole satellite coordinate system;

[0020] The normal direction of the YOZ plane is used as the X-axis direction of the whole star coordinate system;

[0021] The first and second protruding surfaces are measured, and the projection line of the fitted surface on the satellite YOZ plane is used as the Y-axis; or the third and fourth protruding surfaces are measured, and the projection line of the fitted surface on the satellite YOZ plane is used as the Z-axis.

[0022] The third coordinate axis is determined according to the right-hand rule.

[0023] In the method for measuring the installation position of the end probe of the on-board reel-type extension rod mechanism, when the first boss surface and the second boss surface, the satellite-rocket docking surface, the outer surface of the elastic reel storage box, and the mounting surface of the mounting base can be observed simultaneously, the first boss surface and the second boss surface are measured and fitted, and the projection line of the fitted surface on the satellite YOZ plane is used as the Y-axis.

[0024] In the method for measuring the installation position of the end probe of the on-board reel-type extension mechanism, when the third and fourth protruding surfaces, the satellite-rocket docking surface, the outer surface of the elastic reel storage box, and the mounting surface of the mounting base can be observed simultaneously, the third and fourth protruding surfaces are measured and fitted, and the projection line of the fitted surface on the satellite YOZ plane is taken as the Z-axis direction.

[0025] In the method for measuring the installation position of the end probe of the on-board retractor mechanism, in step three, when measuring the measurement reference of the retractor mechanism, the satellite and the laser tracker maintain the state in step two and do not move. The laser tracker is used to measure the measurement reference of the retractor mechanism.

[0026] The advantages of this invention compared to existing technologies are as follows: The method for measuring the installation position of the end probe of the onboard retractor mechanism of this invention achieves the position measurement of the electric field detector probe at the end of the retractor mechanism with a relatively simple reference structure and measurement steps. Utilizing the structural features of the retractor mechanism itself as the measurement reference, it does not introduce additional parts or features beyond its functional performance, such as precision measurement reference mirrors or pin holes. The measurement reference is cleverly set, the measurement steps are simple, and it does not involve coupling between the retractor mechanism and the satellite structure development process before satellite installation. Four protruding surfaces are set on the side of the satellite base plate as satellite quadrant measurement references, and the structural features of the docking ring itself are used as the measurement references for the YOZ plane and the origin. Precise measurement and transmission are achieved with a relatively simple reference structure, with almost no increase in the satellite's development difficulty or weight. In the field of electromagnetic monitoring satellites, this invention is the first to achieve indirect measurement of the actual installation positions of four onboard retractor mechanisms and electric field detector probes in a three-dimensional layout on the satellite, thereby calculating the actual installation position relationship of the four onboard retractor mechanisms and electric field detector probes in a three-dimensional layout on the satellite. The method of the present invention can be used to measure the installation position of the end probe of the roll-type extension mechanism of electromagnetic monitoring satellites, and can also be used to measure the position of the end sensor of other configurations of roll-type extension mechanisms after adjusting the design parameters according to different design requirements. Attached Figure Description

[0027] Figure 1 This is a schematic diagram of the deployed state of the satellite's on-orbit extension mechanism according to the present invention;

[0028] Figure 2 This is a schematic diagram of the measurement reference for the drum-type extension rod mechanism of the present invention;

[0029] Figure 3 This is a schematic diagram of the satellite structure measurement reference of the present invention;

[0030] Figure 4 This is a cross-sectional view of the docking ring of the present invention;

[0031] Figure 5 This is a schematic diagram illustrating the measurement process of the actual positional relationship between two electric field detector probes in the unfolded state of the drum-type extension mechanism. Detailed Implementation

[0032] like Figure 1 As shown, the satellite has four sets of retractable extension rod mechanisms 520, and four electric field detector probes 600 are respectively installed at the ends of the four retractable extension rod mechanisms 520. The four sets of retractable extension rod mechanisms 520 have the same structure, as shown below. Figure 2As shown, both include an elastic drum storage box 521 and a mounting base 522. The elastic drum storage box 521 is fixedly installed on the mounting base 522 and is cylindrical. The electric field detector probe 600 is installed at the end of the telescopic rod of the drum-type extension rod mechanism 520.

[0033] like Figure 3 As shown, a first protruding surface T1 and a second protruding surface T2 are provided on the positive Z side of the satellite structure base plate 120; a third protruding surface T3 and a fourth protruding surface T4 are provided on the negative Y side. All four protruding surfaces T1, T2, T3, and T4 protrude outwards from the outer surface of the satellite body and serve as the position reference for the entire satellite coordinate system during subsequent measurements. The first and second protruding surfaces T1 and T2 are coplanar, as are the third and fourth protruding surfaces T3 and T4. These surfaces must meet certain dimensional and accuracy requirements; for example, the flatness of the first and second protruding surfaces T1 and T2 should not exceed 0.05 mm, and the flatness of the third and fourth protruding surfaces T3 and T4 should not exceed 0.05 mm.

[0034] The method for measuring the installation position of the end probe of the onboard drum-type extension rod mechanism includes,

[0035] Step 1: Before satellite installation, based on the measurement reference of the roll-type extension mechanism 520, measure the unfolded elongation and unfolding angle of the electric field detector probe 600.

[0036] Specifically, the outer surface of the elastic drum storage box 521 and the mounting surface of the mounting base 522 are used as the measurement references for the drum-type extension rod mechanism 520; the extension direction of the central axis of the outer surface of the elastic drum storage box 521 is the extension rod unfolding direction, and the intersection of the central axis and the mounting surface on the mounting base 522 is the origin of the extension rod unfolding direction.

[0037] During measurement, the change in the electric field probe 600 along the extension direction of the drum-type extension mechanism 520 during its unfolding process is the unfolded elongation. After the drum-type extension mechanism 520 is unfolded, the angle between the line connecting the electric field probe 600 and the origin of the extension direction and the central axis is the unfolding angle. Multiple measurements are generally required to obtain the dimensional range of the unfolded elongation and unfolding angle.

[0038] Step 2: Establish the whole star coordinate system.

[0039] Specifically, the positions of the first boss surface T1, the second boss surface T2, the star-rocket docking surface 111, the outer surface of the elastic reel storage box 521, and the mounting surface of the mounting base 522 are selected to be simultaneously observable, or the positions of the third boss surface T3, the fourth boss surface T4, the star-rocket docking surface 111, the outer surface of the elastic reel storage box 521, and the mounting surface of the mounting base 522 are simultaneously observable. A laser tracker is used to measure and establish the entire satellite coordinate system.

[0040] like Figure 3 and Figure 4 As shown, the satellite docking ring 110 and the satellite-rocket docking surface 111 are measured and fitted, and the fitted surface is used as the YOZ surface of the whole satellite coordinate system.

[0041] Measure and fit the lower outer circumferential surface 112 of the satellite docking ring. The center of the lower outer circumferential surface 112 of the satellite docking ring is projected onto the satellite YOZ plane as the origin of the whole satellite coordinate system.

[0042] The normal direction of the YOZ plane is used as the X-axis direction of the whole star coordinate system;

[0043] Based on the position of the drum-type extension mechanism 520 on the satellite, measure and fit the Y-axis or Z-axis; the third direction is determined according to the right-hand rule.

[0044] When the first boss surface T1, the second boss surface T2, the satellite-rocket docking surface 111, the outer surface of the elastic reel storage box 521, and the mounting surface of the mounting base 522 can be observed simultaneously, the first boss surface T1 and the second boss surface T2 are measured and fitted, and the projection line of the fitted surface on the satellite YOZ plane is taken as the Y-axis. When the third boss surface T3, the fourth boss surface T4, the satellite-rocket docking surface 111, the outer surface of the elastic reel storage box 521, and the mounting surface of the mounting base 522 can be observed simultaneously, the third boss surface T3 and the fourth boss surface T4 are measured and fitted, and the projection line of the fitted surface on the satellite YOZ plane is taken as the Z-axis direction.

[0045] Step 3: In the whole satellite coordinate system, measure the outer surface of the elastic drum storage box 521 and the mounting surface of the mounting base 522, and respectively fit the position of the origin of the drum extension mechanism 520 in the satellite and the angle of the extension direction in the satellite.

[0046] During measurement, the satellite and laser tracker remain in the same state as in step three and do not move. The laser tracker is used to measure the outer surface of the elastic roll storage box 521 and the mounting surface of the mounting base 522 respectively.

[0047] Step 4: Based on the dimensional range of the extended length and extended angle of the electric field detector probe 600 measured in Step 1, the position of the origin of the extended direction of the roll-type extension mechanism 520 on the satellite and the angle of the extension direction on the satellite measured in Step 3, calculate the actual installation position relationship of the electric field detector probe 600 on the satellite in the extended state on orbit.

[0048] Taking the measurement of the first electric field detector probe and the second electric field detector probe as an example, such as Figure 5 As shown; the method for measuring the actual installation position relationship of the two electric field detector probes 600 on the satellite is as follows:

[0049] 1) Using the measurement reference of the first electric field detector probe and the second electric field detector probe's own drum-type extension rod mechanism 520, establish the first extension rod coordinate system L respectively. g1 Second extension rod coordinate system L g2 With the origin of the extension rod's unfolding direction as the origin of the coordinate system, and the extension rod's unfolding direction as one of the coordinate axes;

[0050] The extended length L1 and the extended angle θ1 of the probe of the first electric field detector were measured.

[0051] The extended length L2 and the extended angle θ2 of the second electric field detector probe were measured.

[0052] 2) The measured and established whole-satellite coordinate system is L z .

[0053] 3) By measuring the position of the origin of the roll-type extension mechanism 520 on the satellite and the angle of the extension direction on the satellite, the coordinate system L of the first extension rod can be obtained. g1 Second extension rod coordinate system L g2 The vector of the origin of the coordinate system in the whole star coordinate system is r. g1 r g2 ;

[0054] The angles between the first extension rod axis of the first electric field detector probe and the three coordinate axes of the whole satellite coordinate system are set as α1, β1, and γ1; the angles between the second extension rod axis of the second electric field detector probe and the three coordinate axes of the whole satellite coordinate system are set as α2, β2, and γ2.

[0055] Then the axial vector r of the first extension rod s1 It can be represented as:

[0056] r s1 =(L1cosα1,L1cosβ1,L1cosγ1)

[0057] The axial vector of the second extension rod is r s2 It can be represented as:

[0058] r s2 =(L2cosα2,L2cosβ2,L2cosγ2).

[0059] 4) The vector of the spherical head of the first electric field detector probe in the whole-satellite coordinate system is:

[0060] r s1z =r g1 +r s1 .

[0061] Similarly,

[0062] The center of the second electric field detector probe in the whole-satellite coordinate system L is obtained. z The vector r below s2z .

[0063] The distance D between the centers of the first and second electric field detector probes 12 for:

[0064] D 12 =r s2z -r s1z .

[0065] After the center of the first electric field detector probe deviates from the original center by an angle θ1, the distance between the probe and the original center is Δd1:

[0066] Δd1=|r s1 |θ1

[0067] After the center of the second electric field detector probe deviates from the original center by an angle θ2, the distance between the probe and the original center is Δd2.

[0068] Δd2=|r s2 |θ2

[0069] Ultimately, the range of distances between the two ball centers after considering the deviation of the extension rod can be obtained:

[0070] |D 12 |-Δd1-Δd2<|D 12 '|<|D 12 |+Δd1+Δd2

[0071] Using the above method, measurements were obtained.

[0072] The coordinates of the origin of the first electric field detector probe in the whole satellite coordinate system are [25.0, -425.0, 517.7]. The angle between the extension direction of the extension rod and the three coordinate axes of the whole satellite is [89.8, 179.7, 90.2]. The measured extension length is 4423.03 mm and 4423.1 mm. Adding the ball head installation size, the calculated value is L1 = 4491 mm, without considering the variation. The extension angle is 0.12-0.28°, and the maximum value θ1 = 0.28° is taken.

[0073] The coordinates of the origin of the second electric field detector probe's deployment direction in the whole satellite coordinate system are [374.2, -70.2, -847.1]. ​​The angles between the extension direction of the extension rod and the three coordinate axes of the whole satellite are [135.2, 89.8, 134.7]. The measured extension lengths are 4423.01 mm and 4423.5 mm. Adding the ball head installation dimensions, the calculated value is L2 = 4491 mm, without considering any variation. The deployment angle is 0.05-0.09°, and the calculated maximum value is θ2 = 0.09°.

[0074] Substituting into the above calculation process, we obtain the range of distances between the centers of the spheres:

[0075]

[0076] Using the above method, the actual installation position relationship of the four electric field detector probes 600 on the satellite can be calculated when the on-orbit extension rod is deployed.

[0077] As can be seen, the method for measuring the installation position of the end probe of the three-dimensional roll-type extension rod mechanism on the satellite in this invention achieves precise measurement and transmission through the above steps with a relatively simple reference structure and measurement steps. It can conveniently realize the indirect measurement of the actual installation position of the four three-dimensional roll-type extension rod mechanisms and electric field detector probes on the satellite, meeting the needs of related satellites in the field of electromagnetic monitoring.

[0078] The above embodiments are merely examples of applications of the present invention. Those skilled in the art can make various improvements and substitutions based on different design requirements and parameters without departing from the technical solution of the present invention, and these improvements and substitutions will also fall within the protection scope of the present invention.

[0079] The contents not described in detail in this specification are common knowledge to those skilled in the art.

Claims

1. A method for measuring the installation position of the end probe of an onboard drum-type extension rod mechanism, characterized in that: Includes the following steps, Step 1: Before satellite installation, based on the measurement reference of the reel-type extension rod mechanism (520), measure and obtain the size range of the unfolded elongation and unfolding angle of the electric field detector probe (600); Step 2: Establish the whole star coordinate system; Step 3: In the whole satellite coordinate system, measure the measurement reference of the drum-type extension rod mechanism (520), and fit the position of the origin of the extension direction of the drum-type extension rod mechanism (520) on the satellite and the angle of the extension rod extension direction on the satellite respectively; Step 4: Based on the size range of the extension and extension angle of the electric field detector probe (600) measured in Step 1, the position of the origin of the extension direction of the drum-type extension rod mechanism (520) on the satellite and the angle of the extension rod extension direction on the satellite measured in Step 3, calculate the actual installation position relationship of the electric field detector probe (600) on the satellite in the on-orbit extension rod extension state. In step one, the outer surface of the elastic drum storage box (521) and the mounting surface of the mounting base (522) are used as the measurement reference for the drum-type extension rod mechanism (520); The extension direction of the extension rod is the direction of the central axis extending from the outer surface of the elastic roll storage box (521), and the intersection of the central axis and the mounting surface on the mounting base (522) is the origin of the extension rod extension direction. On the Z-side of the satellite structure base plate (120), a first protrusion (T1) and a second protrusion (T2) are provided; the first protrusion (T1) and the second protrusion (T2) are coplanar and both protrude outward from the outer surface of the satellite body on which they are located; And / or on the negative Y side of the satellite structure base plate (120), a third protrusion (T3) and a fourth protrusion (T4) are provided; the third protrusion (T3) and the fourth protrusion (T4) are coplanar and both protrude outward from the outer surface of the satellite body on which they are located; In step two, the first convex surface (T1) and the second convex surface (T2) or the third convex surface (T3) and the fourth convex surface (T4) are used as the position reference of the whole star coordinate system.

2. The method for measuring the installation position of the end probe of the on-board drum-type extension rod mechanism according to claim 1, characterized in that: The flatness of the first boss surface (T1) and the second boss surface (T2) is no greater than 0.05 mm; the flatness of the third boss surface (T3) and the fourth boss surface (T4) is no greater than 0.05 mm.

3. The method for measuring the installation position of the end probe of the on-board drum-type extension rod mechanism according to claim 1, characterized in that: In step two, select a position where the outer surfaces of the first boss surface (T1), the second boss surface (T2), the star-rocket docking surface (111), the elastic reel storage box (521), and the mounting surface of the mounting base (522) can be observed simultaneously, or where the positions of the third boss surface (T3), the fourth boss surface (T4), the star-rocket docking surface (111), the outer surfaces of the elastic reel storage box (521), and the mounting surface of the mounting base (522) can be observed simultaneously, and use a laser tracker to measure and establish the whole star coordinate system.

4. The method for measuring the installation position of the end probe of the on-board drum-type extension rod mechanism according to claim 3, characterized in that: Measure and fit the satellite docking ring (110) and the satellite-rocket docking surface (111) as the YOZ surface of the whole satellite coordinate system; Measure and fit the lower outer circumferential surface (112) of the satellite docking ring. The center of the lower outer circumferential surface (112) of the satellite docking ring is projected onto the satellite YOZ plane as the origin of the whole satellite coordinate system. The normal direction of the YOZ plane is used as the X-axis direction of the whole star coordinate system; Measure the first convex surface (T1) and the second convex surface (T2), and use the projection line of the fitted surface on the satellite YOZ plane as the Y-axis; or measure the third convex surface (T3) and the fourth convex surface (T4), and use the projection line of the fitted surface on the satellite YOZ plane as the Z-axis. The third coordinate axis is determined according to the right-hand rule.

5. The method for measuring the installation position of the end probe of the on-board drum-type extension rod mechanism according to claim 3, characterized in that: When the first boss surface (T1) and the second boss surface (T2), the satellite docking surface (111), the outer surface of the elastic roll storage box (521), and the mounting surface of the mounting base (522) can be observed simultaneously, the first boss surface (T1) and the second boss surface (T2) are measured and fitted, and the projection line of the fitted surface on the satellite YOZ plane is used as the Y-axis.

6. The method for measuring the installation position of the end probe of the on-board drum-type extension rod mechanism according to claim 3, characterized in that: When the third protrusion (T3) and the fourth protrusion (T4), the satellite docking surface (111), the outer surface of the elastic roll storage box (521), and the mounting surface of the mounting base (522) can be observed simultaneously, the third protrusion (T3) and the fourth protrusion (T4) are measured and fitted, and the projection line of the fitted surface on the satellite YOZ plane is taken as the Z-axis direction.

7. The method for measuring the installation position of the end probe of the on-board drum-type extension rod mechanism according to claim 3, characterized in that: In step three, when measuring the measurement reference of the reel-type extension rod mechanism (520), the satellite and the laser tracker maintain the state in step two and do not move. The laser tracker is used to measure the measurement reference of the reel-type extension rod mechanism (520).

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