Device for measuring photogrammetric control points

Abstract

The application discloses an apparatus for measuring photogrammetric control points. The device comprises a plane coordinate frame used for determining plane xy coordinates of photogrammetry control points; the positioning component is used for positioning the photogrammetry control point, and the plane xy coordinate of the photogrammetry control point is determined based on the plane coordinate frame after the positioning component positions the photogrammetry control point; and the height coordinate part determines the height z coordinate of the photogrammetry control point based on the height coordinate part after the positioning part positions the photogrammetry control point. Therefore, the photogrammetry control points in a small range can be measured.

Description

Technical Field

[0001] This application relates to the field of positioning measurement, and more specifically, to an apparatus for measuring photogrammetric control points. Background Technology

[0002] Global Positioning System-Real-Time Kinematic (GPS-RTK) is a positioning technology that dynamically measures the coordinates of a point. A GPS-RTK system consists of a base station and a rover. The rover receives differential correction data and satellite signals from the base station and processes them in real time to correct its own positioning errors, thus achieving centimeter-level high-precision positioning. Global Navigation Satellite System-Real-Time Kinematic (GNSS-RTK) is a high-precision differential positioning technology based on carrier phase observations. By processing carrier phase observations between the base station and the rover in real time, it can provide centimeter-level positioning accuracy.

[0003] GPS-RTK and GNSS-RTK are suitable for photogrammetric control point surveying over large areas. For smaller areas of photogrammetric control point surveying, such as observation areas affected by soil erosion and gully formation, there are currently no effective equipment or methods.

[0004] How to measure photogrammetric control points within a relatively small area has become a technical problem that needs to be solved in this field. Utility Model Content

[0005] In view of this, this application proposes an apparatus for measuring photogrammetric control points, so as to realize the measurement of photogrammetric control points over a small area.

[0006] This application provides an apparatus for measuring photogrammetric control points. The apparatus includes: a plane coordinate frame for determining the plane xy coordinates of the photogrammetric control points; a positioning component for positioning the photogrammetric control points, wherein the positioning component determines the plane xy coordinates of the photogrammetric control points based on the plane coordinate frame after positioning the photogrammetric control points; and a height coordinate component for determining the height z coordinate of the photogrammetric control points based on the height coordinate component after positioning the photogrammetric control points.

[0007] Optionally, the planar coordinate frame includes: a first upright, a second upright, a third upright, and a fourth upright, the first upright, the second upright, the third upright, and the fourth upright being distributed at the four vertices of a rectangle; a first horizontal bar, a second horizontal bar, a third horizontal bar, and a fourth horizontal bar, the first horizontal bar connecting the first upright and the second upright, the second horizontal bar connecting the third upright and the fourth upright, the third horizontal bar connecting the first upright and the third upright, and the fourth horizontal bar connecting the second upright and the fourth upright, the first horizontal bar, the second horizontal bar, the third horizontal bar, and the fourth horizontal bar forming a rectangle, the first horizontal bar and / or the second horizontal bar, the third horizontal bar and / or the fourth horizontal bar having scales for determining the planar xy coordinates.

[0008] Optionally, at least one of the following groups are connected by right-angle connecting members: the first upright with the first horizontal bar and the third horizontal bar, the second upright with the first horizontal bar and the fourth horizontal bar, the third upright with the second horizontal bar and the third horizontal bar, and the fourth upright with the second horizontal bar and the fourth horizontal bar.

[0009] Optionally, the right-angle connecting member is connected to a horizontal adjusting nut.

[0010] Optionally, each of the at least one group includes a horizontal bar equipped with a levelness measuring element.

[0011] Optionally, the levelness measuring element is a level.

[0012] Optionally, the positioning component includes: a first slide rod and a second slide rod, slidably connected to the planar coordinate frame, the first slide rod and the second slide rod being parallel to the two coordinate directions of the planar xy coordinates respectively; and a slider, the first slide rod and the second slide rod passing through the slider respectively, the slider sliding along the first slide rod and the second slide rod to position the photogrammetric control point.

[0013] Optionally, the height coordinate component is a positioning rod, which is perpendicular to the plane containing the first slide rod and the second slide rod and passes through the slider.

[0014] Optionally, the device further includes a control point marking component, which is placed at the photogrammetric control point.

[0015] Optionally, the control point marking component is a positioning pin.

[0016] According to the technical solution of this application, the positioning component positions the photogrammetric control point. After positioning the photogrammetric control point, the planar xy coordinates and height z coordinates of the photogrammetric control point are determined based on the plane coordinate frame and the height coordinate component, respectively, thereby determining the three-dimensional coordinates of the photogrammetric control point and measuring the photogrammetric control point. In the technical solution of this application, the measurement range is determined based on the plane coordinate frame, which can cover a small range, thereby enabling the measurement of photogrammetric control points within a small range.

[0017] Other features and advantages of this application will be described in detail in the following detailed description section. Attached Figure Description

[0018] The accompanying drawings, which form part of this application, are used to provide a further understanding of this application, and the illustrative embodiments and descriptions thereof are used to explain this application. In the drawings:

[0019] Figure 1 This is a schematic diagram of the structure of a device for measuring photogrammetric control points according to a preferred embodiment of this application;

[0020] Figure 2 This is a schematic diagram illustrating the application of a preferred embodiment of the apparatus for measuring photogrammetric control points according to this application;

[0021] Figure 3 This is a top view of an apparatus for measuring photogrammetric control points according to a preferred embodiment of this application;

[0022] Figure 4 This is a front view of an apparatus for measuring photogrammetric control points according to a preferred embodiment of this application;

[0023] Figure 5 This is a left view of an apparatus for measuring photogrammetric control points according to a preferred embodiment of this application;

[0024] Figure 6 This is a top view of the right-angle connecting member and the horizontal adjusting nut according to a preferred embodiment of this application;

[0025] Figure 7 This is a right view of the right-angle connecting member and the horizontal adjusting nut according to a preferred embodiment of this application;

[0026] Figure 8 This is a top view of the slider according to a preferred embodiment of this application;

[0027] Figure 9 This is a front view of the slider according to a preferred embodiment of this application;

[0028] Figure 10 This is a right view of the slider according to a preferred embodiment of this application;

[0029] Figure 11 This is a side view of the pole according to a preferred embodiment of this application;

[0030] Figure 12 This is a top view of the positioning pin according to a preferred embodiment of this application;

[0031] Figure 13 This is a side view of the positioning pin according to a preferred embodiment of this application;

[0032] Figure 14 This is a side view of the positioning rod according to a preferred embodiment of this application;

[0033] Figure 15 This is a front view of the first crossbar according to a preferred embodiment of this application;

[0034] Figure 16 This is a front view of the third crossbar according to a preferred embodiment of this application;

[0035] Figure 17 This is a top view of the first slide bar according to a preferred embodiment of this application;

[0036] Figure 18 This is a front view of the first slide bar according to a preferred embodiment of this application;

[0037] Figure 19 This is a front view of the second slide bar according to a preferred embodiment of this application;

[0038] Figure 20 A top view of the second slide bar according to a preferred embodiment of this application; and

[0039] Figure 21 This is a side view of the second slide bar according to a preferred embodiment of this application. Detailed Implementation

[0040] The technical solution of this application will now be described in detail with reference to the accompanying drawings and embodiments.

[0041] This application provides an apparatus for measuring photogrammetric control points, which can measure the three-dimensional coordinates of the photogrammetric control points.

[0042] The technical solution provided in this application can be applied to many aspects. For example, after measuring the three-dimensional coordinates of photogrammetric control points, these control points are laid out (i.e., marked). Using photogrammetry, soil erosion surfaces of slopes at different periods are generated using these control points. Each erosion surface is then imported into a three-dimensional modeling software system to create a three-dimensional model of soil erosion, calculate soil loss, and study the development and change process of soil erosion gullies. By using the technical solution provided in this application to determine the three-dimensional coordinates of the photogrammetric control points, conditions are created for subsequent three-dimensional soil erosion gully extraction, soil erosion calculation, and research on the development process and influencing factors of soil erosion gullies through modeling.

[0043] The technical solution provided in this application can be applied to measuring photogrammetric control points within a relatively small area. For example, the measurement range can be within a few square meters, such as 2 square meters. Alternatively, it can be applied to soil erosion in the form of fine gullies. For example, it can be used to establish control points for photogrammetric surveying of erosion gullies with a length of less than 3 meters and a width of less than 0.5 meters.

[0044] The technical solution provided in this application can be applied to natural slopes, such as... Figure 2 As shown, it is difficult to accurately determine the three-dimensional coordinates of control points on natural slopes using conventional surveying tools. When the accuracy of photogrammetric control point data does not meet the requirements, the accuracy of the mesh produced by photogrammetric surveying of slope gully erosion will be affected, and three-dimensional modeling and subsequent accurate measurement of soil erosion will also be difficult to achieve. The technical solution provided by the embodiments of this application can accurately determine the three-dimensional coordinates of photogrammetric control points on natural slopes, thereby avoiding the technical problems caused by the insufficient accuracy of photogrammetric control point data.

[0045] The apparatus for measuring photogrammetric control points provided in this application embodiment may include the following: a plane coordinate frame, a positioning component, and a height coordinate component.

[0046] A plane coordinate frame is used to determine the plane xy coordinates of photogrammetric control points.

[0047] The positioning component is used to locate photogrammetric control points. After locating the photogrammetric control points, the positioning component determines the planar xy coordinates of the photogrammetric control points based on a plane coordinate frame. For example, the plane coordinate frame can be used to mark or measure the planar xy coordinates. After the photogrammetric control points to be measured are located, the planar xy coordinates can be determined based on the plane coordinate frame.

[0048] After the positioning component locates the photogrammetric control point, it determines the z-coordinate of the photogrammetric control point based on the height coordinate component. For example, the height coordinate component can mark or measure the z-coordinate of the height, and after the photogrammetric control point to be measured is located, the z-coordinate of the height can be determined based on the height coordinate component.

[0049] Optionally, in this embodiment, the planar coordinate frame includes a first upright 10, a second upright 11, a third upright 12, a fourth upright 13, a first horizontal bar 20, a second horizontal bar 21, a third horizontal bar 22, and a fourth horizontal bar 23. The four uprights can be referenced... Figure 11 Let's try to understand it.

[0050] like Figure 1 or Figure 2 As shown, the first upright 10, the second upright 11, the third upright 12, and the fourth upright 13 are distributed at the four vertices of the rectangle. Figure 1 or Figure 2 As shown, the first horizontal bar 20 connects the first vertical bar 10 and the second vertical bar 11; the second horizontal bar 21 connects the third vertical bar 12 and the fourth vertical bar 13; the third horizontal bar 22 connects the first vertical bar 10 and the third vertical bar 12; and the fourth horizontal bar 23 connects the second vertical bar 11 and the fourth vertical bar 13. The first horizontal bar 20, the second horizontal bar 21, the third horizontal bar 22, and the fourth horizontal bar 23 form a rectangle. The first horizontal bar 20 and / or the second horizontal bar 21, the third horizontal bar 22, and / or the fourth horizontal bar 23 have scales for determining the xy coordinates of the plane.

[0051] In this embodiment, the first crossbar 20 and the second crossbar 21 are parallel, and at least one of them has a scale. Similarly, at least one of the third crossbar 22 and the fourth crossbar 23 has a scale.

[0052] In this embodiment, the first crossbar 20 and the third crossbar 22 are equipped with scales, wherein the scale of the first crossbar 20 can be referenced. Figure 15 As shown, the scale of the third horizontal bar 22 can be referenced. Figure 16 As shown.

[0053] In this embodiment, the first crossbar 20, the second crossbar 21, the third crossbar 22, and the fourth crossbar 23 may have fixing strips 80 for easy fixing. Figure 15 As shown, for the first crossbar 20, fixing strips 80 are distributed at both ends of the first crossbar 20. Figure 16 As shown, for the second crossbar 21, the fixing strips 80 are distributed at both ends of the second crossbar 21. For the third crossbar 22 and the fourth crossbar 23, the fixing strips 80 are also distributed at both ends of the crossbar, as can be seen from... Figure 15 or Figure 16 Let's try to understand it.

[0054] In this application embodiment, there are many ways to connect the uprights and crossbars. For example, right-angle connecting members can be used. Specifically, in this application embodiment, at least one of the following groups is connected by right-angle connecting members 30: the first upright 10 is connected to the first crossbar 20 and the third crossbar 22; the second upright 11 is connected to the first crossbar 20 and the fourth crossbar 23; the third upright 12 is connected to the second crossbar 21 and the third crossbar 22; and the fourth upright 13 is connected to the second crossbar 21 and the fourth crossbar 23. In this application embodiment, each upright connects to two crossbars, and at least one upright is connected to two crossbars by a right-angle connecting member 30. Figure 1 or Figure 2 As shown, each upright is connected to two horizontal bars via a right-angle connecting member 30.

[0055] Optionally, in this embodiment, the right-angle connecting member 30 is connected to a horizontal adjusting nut 31 for leveling. Figure 3 As shown, each right-angle connecting member 30 is connected to a horizontal adjusting nut 31. The relationship between the right-angle connecting member 30 and the horizontal adjusting nut 31 can be referred to... Figure 6 and Figure 7 To understand.

[0056] Optionally, in this embodiment, at least one group of crossbars includes a leveling measuring element. In other words, in this embodiment, for the uprights and crossbars connected by the right-angle connecting member 30, the crossbars are equipped with leveling measuring elements. Optionally, in this embodiment, the leveling measuring element may be a level 40.

[0057] like Figure 3 As shown, the first upright 10 is connected to the first horizontal bar 20 and the third horizontal bar 22, the second upright 11 is connected to the first horizontal bar 20 and the fourth horizontal bar 23, the third upright 12 is connected to the second horizontal bar 21 and the third horizontal bar 22, and the fourth upright 13 is connected to the second horizontal bar 21 and the fourth horizontal bar 23 through right-angle connecting members 30. The first horizontal bar 20, the second horizontal bar 21, the third horizontal bar 22 and the fourth horizontal bar 23 are all equipped with a level 40.

[0058] Optionally, in this embodiment, the positioning component includes: a first slide rod 50, a second slide rod 51, and a slider 52. The first slide rod 50 and the second slide rod 51 are slidably connected to a plane coordinate frame, and the first slide rod 50 and the second slide rod 51 are parallel to the two coordinate directions of the plane xy coordinate system, respectively. The first slide rod 50 and the second slide rod 51 pass through the slider 52, and the slider 52 slides along the first slide rod 50 and the second slide rod 51 to locate photogrammetric control points. The slider 52 can be referenced... Figure 8 , Figure 9 and Figure 10 To understand.

[0059] like Figures 1 to 5 As shown, the first slide bar 50 is parallel to the first crossbar 20 and the second crossbar 21, and the second slide bar 51 is parallel to the third crossbar 22 and the fourth crossbar 23. The first slide bar 50 and the second slide bar 51 are located on different planes that are parallel to the planes where the first crossbar 20 and the third crossbar 22 are located.

[0060] like Figure 17 or Figure 18 As shown, the first slide bar 50 has first reserved holes 501 at both ends, and the third crossbar 22 and the fourth crossbar 23 pass through the two first reserved holes 501 respectively. Figure 19 , Figure 20 or Figure 21 As shown, the second slide bar 51 has slide bar uprights 511 at both ends, and each slide bar upright 511 has a second reserved hole 513. The first crossbar 20 and the second crossbar 21 pass through a second reserved hole 513 respectively.

[0061] like Figure 17 As shown, the first slider 50 has a first slider groove 502. (As indicated...) Figure 20 As shown, the second slider 51 has a second slider groove 512. The slider 52 can slide along the first slider groove 502 or the second slider groove 512 to align the slider 52 with the photogrammetric control point. After the slider 52 is aligned with the photogrammetric control point, the planar xy coordinates of the photogrammetric control point can be determined based on the values ​​of the scales aligned on the crossbar by the first slider 50 and the second slider 51, respectively. In this embodiment, the origin of the planar coordinates can be selected according to specific circumstances; for example, the intersection of two crossbars can be used as the origin.

[0062] Optionally, in this embodiment, the height coordinate component is a positioning rod 60. For example... Figure 1 or Figure 2 As shown, the positioning rod 60 is perpendicular to the plane containing the first slide bar 50 and the second slide bar 51 and passes through the slider 52. The positioning rod 60 has a scale. After the slider 52 is aligned with the photogrammetric control point, the positioning rod 60 is inserted into the slider 52, and the height z-coordinate of the photogrammetric control point is determined based on the scale on the positioning rod 60. Specifically, after the positioning rod 60 reaches the photogrammetric control point, the height z-coordinate is determined based on the value aligned with the slider 52 on the scale of the positioning rod 60.

[0063] In this embodiment of the application, the photogrammetric control points can be determined based on the actual application scenario and measurement range. For example... Figure 2 As shown, it is necessary to study soil erosion, and five photogrammetric control points were selected on the slope surface.

[0064] Specifically, the height z-coordinate of the photogrammetric control point can be determined based on the positioning rod 60 according to the following: After the positioning rod 60 is inserted into the slider 52 and reaches the photogrammetric control point, the slider 52 aligns with the scale of the positioning rod 60 to obtain a reading, which is marked as the slider height value. Among all photogrammetric control points, one photogrammetric control point can be selected as the reference point for the height z-coordinate (the point with a height z-coordinate of 0), and the height z-coordinate of this photogrammetric control point is marked as 0. That is, when the slider height value of this photogrammetric control point is converted to the height z-coordinate, the height z-coordinate is 0. For example, the photogrammetric control point with the lowest position can be selected as the reference point for the height z-coordinate. For each of the other photogrammetric control points, the height z-coordinate can be determined based on the relationship between its slider height value and the slider height value of the reference point. For example, if the slider height value of the photogrammetric control point used as the reference point is 30cm, then the height z-coordinate of the photogrammetric control point with a slider height value of 20cm is -10, and the height z-coordinate of the photogrammetric control point with a slider height value of 40cm is 10.

[0065] Optionally, in this embodiment, the slider 52 can be manually controlled to slide, or it can be automatically controlled by a component. For example, a controller and a motor are provided, with the motor driving the slider. Under the control of the controller, the motor controls the slider 52 to slide in two directions.

[0066] Optionally, in this embodiment, the device further includes a control point marking component. The control point marking component is placed at the photogrammetric control point. This achieves the marking of the photogrammetric control point and the establishment of the photogrammetric control point.

[0067] Optionally, in this embodiment, the control point marking component is a positioning pin. Wherein, the positioning pin is as follows: Figure 12 or Figure 13 As shown.

[0068] Optionally, in this embodiment, a magnetic suction head may be provided at the lower end of the positioning rod 60 (i.e., the end to be inserted into the area to be measured), such as... Figure 14 As shown, the positioning pin is magnetically attracted by the magnetic head. After the positioning rod 60 reaches the photogrammetric control point, the positioning pin is placed at the photogrammetric control point. By setting a magnetic head at the lower end of the positioning rod 60 to magnetically attract the positioning pin, and then placing the positioning pin at the photogrammetric control point via the positioning rod, the photogrammetric control point can be marked without manual approach, making it more convenient to mark and deploy photogrammetric control points. Furthermore, by placing positioning pins at the photogrammetric control points, a uniform style can be used to mark the photogrammetric control points.

[0069] In the embodiments of this application, the apparatus provided in the embodiments of this application can be used with reference to the following content.

[0070] After selecting the slope study area, three-dimensional coordinate measurement and layout facilities are arranged in the area to be measured, namely, the device for measuring photogrammetric control points provided in the embodiments of this application. The length of the first horizontal bar 20 is less than the length of the third horizontal bar 22. The long side of the facility is arranged longitudinally along the slope surface, as shown below. Figure 2 As shown, the third horizontal bar 22 and the fourth horizontal bar 23 are arranged longitudinally along the slope, the first vertical bar 10 and the second vertical bar 11 are located at the bottom of the slope, and the third vertical bar 12 and the fourth vertical bar 13 are located at the top of the slope.

[0071] Adjust the leveling nut 31 to keep the plane containing the first crossbar 20, the second crossbar 21, the third crossbar 22, and the fourth crossbar 23 level. You can use a level 40 to determine whether the plane is level.

[0072] After initially selecting photogrammetric control points on the slope, move slider 52 to the control point area along the first slider 50 and the second slider 51, insert positioning rod 60 into slider 52, install positioning nail at the magnetic attachment point at the lower end of positioning rod 60, and insert positioning nail into the selected photogrammetric control points on the slope.

[0073] Read the x-coordinate of the photogrammetric control point at scale 20 on the first horizontal bar, read the y-coordinate of the photogrammetric control point at scale 22 on the third horizontal bar, and read the z-coordinate of the photogrammetric control point at scale 60 on the positioning rod.

[0074] Repeat the above steps to identify all control points and record their three-dimensional coordinates.

[0075] Optionally, in this embodiment, the uprights, crossbars, and sliding bars can be cylindrical rods, and their dimensions can be referenced in the accompanying drawings. The heads of the positioning pins can be numbered using numbers and letters. For example, positioning pins used to mark survey area boundaries can be distinguished by marking letters in the lower right corner of the crosshairs on the pin head: O, X, Y, B; positioning pins used to mark control points can be distinguished by marking numbers in the lower right corner of the crosshairs on the pin head: 00, 01, 02…

[0076] The number of positioning pins can be determined according to the specific situation, and there is no limit to it.

[0077] It should be noted that in the embodiments of this application, "first", "second", "third", "fourth", etc. are only used for distinction and explanation, and are not intended to limit.

[0078] The technical solution provided by the embodiments of this application measures and sets up photogrammetric control points, and marks the photogrammetric control points with names (e.g., the number of the positioning pins). Each photogrammetric control point corresponds to a name and a three-dimensional coordinate, which facilitates subsequent photogrammetry.

[0079] The technical solution provided in this application has a simple facility structure, is easy to operate, has low manufacturing cost, and is convenient for widespread use. Through the technical solution provided in this application, photogrammetric control points in the area to be measured can be quickly and accurately calibrated, creating conditions for subsequent accurate measurement of the mesh surface of the area to be measured, 3D solid modeling of the slope, extraction of erosion gully models, determination of soil erosion, and research on the formation and development patterns of slope gully erosion. This promotes the transformation of slope soil erosion measurement from traditional measurement methods to digital measurement methods.

[0080] The preferred embodiments of this application have been described in detail above. However, this application is not limited to the specific details of the above embodiments. Within the scope of the technical concept of this application, various simple modifications can be made to the technical solution of this application, and these simple modifications all fall within the protection scope of this application.

[0081] It should also be noted that the various specific technical features described in the above specific embodiments can be combined in any suitable way without contradiction. In order to avoid unnecessary repetition, this application will not describe the various possible combinations separately.

[0082] Furthermore, various different implementations of this application can be combined in any way, as long as they do not violate the spirit of this application, they should also be regarded as the content disclosed in this application.

Claims

1. An apparatus for measuring photogrammetric control points, characterized in that, The device includes: A plane coordinate frame is used to determine the plane xy coordinates of photogrammetric control points; A positioning component is used to position the photogrammetric control point. After positioning the photogrammetric control point, the positioning component determines the planar xy coordinates of the photogrammetric control point based on the planar coordinate frame. The height coordinate component determines the height z-coordinate of the photogrammetric control point after the positioning component locates the photogrammetric control point.

2. The apparatus of claim 1, wherein, The planar coordinate frame includes: The first upright, the second upright, the third upright, and the fourth upright are distributed at the four vertices of the rectangle; A first horizontal bar, a second horizontal bar, a third horizontal bar, and a fourth horizontal bar are provided. The first horizontal bar connects the first upright and the second upright. The second horizontal bar connects the third upright and the fourth upright. The third horizontal bar connects the first upright and the third upright. The fourth horizontal bar connects the second upright and the fourth upright. The first horizontal bar, the second horizontal bar, the third horizontal bar, and the fourth horizontal bar form a rectangle. The first horizontal bar and / or the second horizontal bar, the third horizontal bar and / or the fourth horizontal bar have scales for determining the xy coordinates of the plane.

3. The apparatus of claim 2, wherein, At least one of the following groups is connected by right-angle connecting members: the first upright and the first horizontal bar and the third horizontal bar, the second upright and the first horizontal bar and the fourth horizontal bar, the third upright and the second horizontal bar and the third horizontal bar, and the fourth upright and the second horizontal bar and the fourth horizontal bar.

4. The apparatus of claim 3, wherein, The right-angle connecting member is connected to a horizontal adjusting nut.

5. The apparatus of claim 4, wherein, Each of the at least one group includes a horizontal bar equipped with a levelness measuring element.

6. The apparatus of claim 5, wherein, The levelness measuring device is a level.

7. The apparatus of claim 1, wherein, The positioning component includes: A first slide bar and a second slide bar are slidably connected to the planar coordinate frame, and the first slide bar and the second slide bar are respectively parallel to the two coordinate directions of the planar xy coordinate system; and A slider, with a first slide bar and a second slide bar passing through it respectively, slides along the first slide bar and the second slide bar to locate the photogrammetric control point.

8. The apparatus of claim 7, wherein, The height coordinate component is a positioning rod, which is perpendicular to the plane containing the first slide rod and the second slide rod and passes through the slider.

9. The apparatus of claim 1, wherein, The device also includes: A control point marker component is placed at the photogrammetric control point.

10. The apparatus of claim 9, wherein, The control point marking component is a positioning pin.

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