Rearview orientation device and orientation method

Abstract

The invention relates to a rearview orientation device and an orientation method, which are applied to the field of surveying and mapping technologies. The device comprises a coarse sighting piece, a fine sighting piece and a mounting piece, the coarse sighting piece extends in the first direction, and a plurality of coarse sighting spacer regions and coarse sighting identification regions which are alternately arranged are formed on the surface of the coarse sighting piece; the fine sighting piece extends in the first direction and is fixed to the coarse sighting piece, and a plurality of fine sighting interval areas and fine sighting identification areas which are alternately arranged are formed on the surface of the fine sighting piece; the mounting piece is connected to one end, far away from the fine aiming piece, of the coarse aiming piece and is used for fixing the coarse aiming piece and the fine aiming piece on the ground; in the first direction, the projection of the coarse aiming piece on the first datum plane is larger than that of the fine aiming piece on the first datum plane. Through the arrangement of the coarse aiming piece and the fine aiming piece, according to the principle of coarse long-distance aiming and fine short-distance aiming, the problems of aiming errors caused by the distance of sight distance and shielding caused by small topographic relief are solved, the field measurement efficiency is improved, and the safety risk is reduced.

Description

Technical Field

[0001] The present application relates to the field of surveying and mapping technology, and in particular to a rear-view orientation device and an orientation method. Background Art

[0002] In recent years, 3D laser scanning technology has been developing and maturing, and 3D scanning equipment has gradually become commercialized. It uses high-speed laser scanning measurement to quickly obtain 3D coordinate data of the surface of the measured object with high resolution over a large area. It can quickly and massively collect spatial point information, providing a new technical means for quickly establishing a 3D image model of an object. Due to the characteristics of 3D laser scanning technology, such as rapidity, non-contact, penetration, real-time, dynamic, active, high-density, high-precision, digitalization, and automation, it has been highly recognized by the surveying and mapping industry.

[0003] However, some vehicle-mounted scanners require control positioning and rear-view orientation to determine absolute coordinates. During this period, the rear-view orientation points are often determined by manual marking. The surveying technicians need to hold the measuring centering pole and walk about 100 meters away from the site scanner. From instrument centering to smooth measurement, the entire data collection process takes nearly 3-5 minutes, which has a certain degree of impact on the scanning efficiency. In addition, there is a great safety risk when technicians walk back and forth in the construction area. Summary of the invention

[0004] Based on this, it is necessary to provide a rear-view orientation device and orientation method to address the problem that the above-mentioned vehicle-mounted scanner needs to determine the absolute coordinates through manual dot marking, which leads to low surveying efficiency and high surveying risk.

[0005] In a first aspect, the present application provides a rear-view orientation device, which adopts the following technical solution:

[0006] A rear-view orientation device comprises a coarse aiming piece, a fine aiming piece and a mounting piece, wherein the coarse aiming piece extends along a first direction, and a plurality of coarse aiming spacers and coarse aiming marking areas are formed on the surface of the coarse aiming piece along the first direction, and the coarse aiming spacers and the coarse aiming marking areas are arranged one by one; the fine aiming piece extends along the first direction and is fixed to one end of the coarse aiming piece, and a plurality of fine aiming spacers and fine aiming marking areas are formed on the surface of the fine aiming piece, and the fine aiming spacers and the fine aiming marking areas are arranged one by one; the mounting piece is connected to one end of the coarse aiming piece away from the fine aiming piece, and the mounting piece is used to fix the coarse aiming piece and the fine aiming piece to the ground; wherein, along the first direction, the projection of the coarse aiming piece on a first reference plane is larger than the projection of the fine aiming piece on the first reference plane, and the first direction is perpendicular to the first reference plane.

[0007] In one of the embodiments, in the first direction, the total length of the coarse aiming member and the fine aiming member is greater than or equal to 5 m.

[0008] In one of the embodiments, in the first direction, the size of the coarse aiming component is larger than the size of the fine aiming component.

[0009] In one embodiment, in a second direction, the size of the coarse aiming component is greater than the size of the fine aiming component, and the second direction is perpendicular to the first direction.

[0010] In one embodiment, in the first direction, the central axis of the fine aiming member coincides with the central axis of the coarse aiming member.

[0011] In one embodiment, the mounting member includes a frame template and anchor bolts, the frame template is connected to one end of the coarse aiming member away from the fine aiming member, and the anchor bolts are passed through the frame template along the first direction and fixed to the ground.

[0012] In one of the embodiments, the mounting member further includes a base, the frame template and the anchor bolts are both buried in the base, and the base can be buried below the ground.

[0013] In one embodiment, the rearward-looking orientation device further comprises a measuring line, wherein the measuring line is rotatably connected to the coarse aiming component, and the measuring line is configured to be rotatable around a central axis of the coarse aiming component.

[0014] In a second aspect, the present application provides an orientation method, using the rear-view orientation device according to any one of claims 1 to 8, the orientation method comprising the following steps:

[0015] Select the installation location;

[0016] Dig a foundation pit and embed the installation parts to provide an installation foundation;

[0017] Install the coarse aiming parts and the fine aiming parts in sequence;

[0018] Determine the axis coordinates of the rear-view orientation device.

[0019] In one embodiment, digging a foundation pit and pre-burying installation parts to provide an installation foundation includes:

[0020] Dig a foundation pit from the ground to below the permafrost layer at the installation site;

[0021] Lowering the frame formwork and inserting anchor bolts along the first direction;

[0022] Concrete is poured into the pit to form the foundation.

[0023] The above-mentioned rear-sight orientation device, through the setting of coarse aiming parts and fine aiming parts, follows the principle of coarse aiming at a distance and fine aiming at a close distance, solves the aiming error caused by the distance of sight and the obstruction problem caused by small terrain undulations, and expands the observable range of the rear-sight orientation device, thereby eliminating the step of manual positioning before each operation, improving the efficiency of field measurement, reducing the safety risk of human-machine intersection, and effectively avoiding the accuracy error of the rear-sight positioning point caused by frequent manual intervention. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] FIG. 1 is a schematic structural diagram of a rearward-looking orientation device in one embodiment of the present application.

[0025] FIG. 2 is a flow chart of an orientation method in an embodiment of the present application.

[0026] FIG. 3 is a partial flow chart of an orientation method in an embodiment of the present application.

[0027] Notes on the attached drawings:

[0028] 1. Coarse aiming piece; 11. Coarse aiming spacer; 12. Coarse aiming identification area; 2. Fine aiming piece; 21. Fine aiming spacer; 22. Fine aiming identification area; 3. Mounting piece; 31. Frame template; 32. Anchor bolt; 33. Base; F1, first direction; F2, second direction; V1, first reference plane. DETAILED DESCRIPTION

[0029] In order to make the above-mentioned purposes, features and advantages of the present application more obvious and easy to understand, the specific implementation methods of the present application are described in detail below in conjunction with the accompanying drawings. In the following description, many specific details are set forth to facilitate a full understanding of the present application. However, the present application can be implemented in many other ways different from those described herein, and those skilled in the art can make similar improvements without violating the connotation of the present application, so the present application is not limited by the specific embodiments disclosed below.

[0030] In the description of the present application, it should be understood that if the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc. appear, the orientation or position relationship indicated by these terms is based on the orientation or position relationship shown in the accompanying drawings, which is only for the convenience of describing the present application and simplifying the description, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present application.

[0031] In addition, if the terms "first" or "second" appear, these terms are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include at least one of the features. In the description of this application, if the term "plurality" appears, the meaning of "plurality" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0032] In this application, unless otherwise clearly specified and limited, if the terms "installed", "connected", "connected", "fixed" and the like appear, these terms should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integrated connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements, unless otherwise clearly defined. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to the specific circumstances.

[0033] In the present application, unless otherwise clearly specified and limited, if there is a description that a first feature is "above" or "below" a second feature, etc., or similar descriptions appear, it may mean that the first and second features are in direct contact, or that the first and second features are in indirect contact through an intermediate medium. Moreover, the first feature being "above", "above" and "above" the second feature may mean that the first feature is directly above or obliquely above the second feature, or simply means that the first feature is higher in level than the second feature. The first feature being "below", "below" and "below" the second feature may mean that the first feature is directly below or obliquely below the second feature, or simply means that the first feature is lower in level than the second feature.

[0034] It should be noted that if an element is referred to as being "fixed to" or "disposed on" another element, it may be directly on the other element or there may also be a central element. If an element is considered to be "connected to" another element, it may be directly connected to the other element or there may be a central element at the same time. If any, the terms "vertical", "horizontal", "upper", "lower", "left", "right" and similar expressions used in this application are for illustrative purposes only and do not represent the only implementation method. Among them, the "first direction" may be a vertical direction; the "second direction" may be a horizontal direction; and the "first reference plane" may be a horizontal plane.

[0035] As an emerging surveying and mapping technology, 3D laser scanning measurement technology promotes the collection of spatial data in the direction of real-time, high-precision, digital and intelligent development. 3D laser scanning technology, also known as "real scene replication technology", can quickly copy the 3D space dimensions of the site to the computer, and automatically generate 1:1 3D point cloud data on the computer, which can effectively and quickly solve the complex measurement problems on the construction site.

[0036] In recent years, 3D laser scanning technology has been developing and maturing, and 3D scanning equipment has been gradually commercialized. It uses high-speed laser scanning to quickly obtain 3D coordinate data of the surface of the object being measured over a large area and with high resolution. It can quickly and massively collect spatial point information, providing a new technical means for quickly building a 3D image model of an object.

[0037] 3D laser scanning technology has been highly recognized by the surveying and mapping industry due to its rapidity, non-contact, penetration, real-time, dynamic, active, high-density, high-precision, digital, and automated characteristics. However, some vehicle-mounted scanners require control positioning and rear-view orientation to determine absolute coordinates. During this period, the rear-view orientation points are often determined by manual dotting. Surveying technicians need to hold the measurement centering pole and walk about 100 meters away from the site scanner. From instrument centering to smooth measurement, the entire data collection process takes nearly 3-5 minutes, which has a certain degree of impact on scanning efficiency, and there are greater safety risks when walking back and forth in the construction area.

[0038] Therefore, in order to solve the problem that the above-mentioned vehicle-mounted scanner needs to determine the absolute coordinates through manual dot-marking, resulting in low surveying efficiency and high surveying risk, the present application proposes a rear-view orientation device and orientation method for use with a three-dimensional laser scanner.

[0039] Refer to Figure 1, which shows a schematic structural diagram of a rear-view orientation device in an embodiment of the present application. An embodiment of the present application provides a rear-view orientation device for cooperating with a three-dimensional laser scanner to achieve rapid mapping. The rear-view orientation device includes a mounting member 3 for fixing the entire device to the ground. Along a first direction F1, a coarse aiming member 1 and a fine aiming member 2 for an operator to observe are sequentially mounted on the mounting member 3.

[0040] In some embodiments, the coarse aiming piece 1 and the fine aiming piece 2 can be constructed into a cylindrical structure, and can be specifically cut from a steel rod, a steel pipe or other columnar body with a certain structural strength to ensure the service life of the entire device. In addition, in order to reduce the overall deadweight of the device, in the embodiment of the present application, on the premise that the device as a whole has the corresponding structural strength, a hollow steel pipe can be preferably used to manufacture the above-mentioned coarse aiming piece 1 and the fine aiming piece 2. The steel pipe can be a galvanized stainless steel pipe to reduce the situation where the service life of the entire device is shortened due to factors such as rust on the coarse aiming piece 1 and the fine aiming piece 2.

[0041] In addition, in order to ensure the operator's observable range, the total length of the rear-view orientation device in the embodiment of the present application is set to be greater than or equal to 5m, so as to reduce the situation where the rear-view orientation device is covered by obstructions at the surveying site, thereby facilitating the operator to quickly find the rear-view orientation device. At the same time, the expansion of the observable range of a single rear-view orientation device effectively eliminates the step of manual positioning before each operation, improves the efficiency of field measurement, and can also reduce the safety risk of human-machine intersection, while effectively avoiding the accuracy error of the rear-view positioning point caused by frequent manual intervention.

[0042] In addition, when observed along the first direction F1, the projection area of ​​the coarse aiming piece 1 on the first reference plane V1 is larger than the projection area of ​​the fine aiming piece 2 on the first reference plane V1, that is, the size of the coarse aiming piece 1 in the second direction F2 is larger than the size of the fine aiming piece 2 in the second direction F2, that is, the radial size of the coarse aiming piece 1 is larger than the radial size of the fine aiming piece 2. The diameter of the coarse aiming piece 1 is 200 mm, and the diameter of the fine aiming piece 2 is 100 mm.

[0043] In addition, the coarse aiming piece 1 and the fine aiming piece 2 of the rear-view orientation device are made of steel pipes of different diameters, and the overall height of the device is set to be greater than or equal to 5m, so that the operator can follow the principle of coarse aiming at a long distance and fine aiming at a close distance when aiming the rear-view orientation device, thereby solving the aiming error caused by the distance of sight and the obstruction problem caused by small terrain undulations.

[0044] Further, in some embodiments, along the first direction F1, a plurality of coarse aiming spacers 11 and a plurality of coarse aiming marking areas 12 are formed on the surface of the coarse aiming member 1, and the coarse aiming spacers 11 and the coarse aiming marking areas 12 are arranged one by one. A plurality of fine aiming spacers 21 and a plurality of fine aiming marking areas 22 are formed on the surface of the fine aiming member 2, and the fine aiming spacers 21 and the fine aiming marking areas 22 are arranged one by one.

[0045] In order to ensure the observation effect, the coarse aiming marking area 12 and the fine aiming marking area 22 are coated with red paint, and the coarse aiming interval area 11 and the fine aiming interval area 21 can be coated with paint with a large color difference from the red paint or no paint. In the embodiment of the present application, the coarse aiming interval area 11 and the fine aiming interval area 21 are coated with yellow paint, so that the operator can accelerate the positioning of the rear-view positioning device through the reminder of the paint color during the observation process, thereby accelerating the surveying and mapping process.

[0046] Furthermore, in the first direction F1, the sizes of the coarse aiming marking area 12, the coarse aiming spacing area 11, the fine aiming marking area 22 and the fine aiming spacing area 21 are consistent. When the operator observes, he can make a rough judgment on the height size by counting the number of spacing areas and marking areas to further accelerate positioning.

[0047] Continuing to refer to FIG. 1 , in some embodiments, the size of the coarse aiming member 1 in the first direction F1 is greater than the size of the fine aiming member 2 in the first direction F1, thereby ensuring the structural strength of the rearward-looking orientation device as a whole. In the embodiment of the present application, when the size of the rearward-looking orientation device as a whole in the first direction F1 is 5 m, the size of the coarse aiming member 1 in the first direction F1 is set to 4 m, and the size of the fine aiming member 2 in the first direction F1 is set to 1 m.

[0048] In some other embodiments, the size of the coarse aiming member 1 in the first direction F1 can be set to 4.1m, 4.2m or 4.3m, and correspondingly, the size of the fine aiming member 2 in the first direction F1 is set to 0.9m, 0.8m or 0.7m. The specific size design can be adaptively adjusted according to the actual needs of the surveying and mapping site. This is not limited in the embodiments of the present application, as long as the overall structural strength and observation clarity of the rear-view orientation device can be guaranteed.

[0049] In addition, in some other embodiments, in order to speed up assembly, the fine aiming piece 2 can be welded to the top of the coarse aiming piece 1 in advance to facilitate overall transportation during installation. It can be understood that in order to ensure the consistency of the observation data obtained from all around the rear-view orientation device, in the embodiment of the present application, the fine aiming piece 2 should be coaxially welded to the top of the coarse aiming piece 1, that is, in the first direction F1, the central axis of the fine aiming piece 2 and the central axis of the coarse aiming piece 1 coincide.

[0050] In some embodiments, the mounting member 3 includes a frame template 31 and at least one anchor bolt 32. The frame template 31 is fixed to a base plate at the bottom of the coarse aiming member 1. All anchor bolts 32 are passed through the four sides of the frame template 31 along the first direction F1, so as to stably fix the frame template 31, the coarse aiming member 1 and the fine aiming member 2 to the ground to ensure the overall installation stability of the device.

[0051] In some other embodiments, the mounting member 3 further includes a base 33 buried below the ground, and the base 33 can be specifically formed by the solidification of concrete poured into the foundation pit. The above-mentioned anchor bolts 32 pass through the frame template 31 and are inserted into the base 33. When the concrete solidifies, the anchor bolts 32 will be embedded in the base 33 to ensure the stability of the frame template 31 and the coarse aiming member 1 and the fine aiming member 2 installed on the frame template 31.

[0052] In some embodiments, the rear-view orientation device further includes a measuring line (not shown) tied to the coarse aiming piece 1, and one end of the measuring line is fixed 10 cm above the bottom of the coarse aiming piece 1. In the embodiment of the present application, the measuring line can be a thin rope without elasticity, with the central axis of the coarse aiming piece 1 as the axis, and at least three points are taken on the ground at one end of the measuring line of the same length away from the coarse aiming piece 1, and finally the coordinates of the overall axis of the rear-view orientation device are obtained by the method of determining the center of a circle based on three points.

[0053] In combination with FIG. 2 and FIG. 3, FIG. 2 shows a flow chart of an orientation method in an embodiment of the present application, and FIG. 3 shows a partial flow chart of an orientation method in an embodiment of the present application. In some embodiments, the present application further provides an orientation method, using a rear-view orientation device as described in any of the above embodiments, and the orientation method comprises the following steps:

[0054] S1: Select the installation location;

[0055] S2: digging a foundation pit and pre-burying the installation parts 3 to provide an installation foundation;

[0056] S3: Install the coarse aiming piece 1 and the fine aiming piece 2 in sequence;

[0057] S4: Determine the axis coordinates of the rear-view orientation device.

[0058] Wherein, step S1 specifically includes the following point selection requirements:

[0059] (1) The installation site should be selected in an area with a stable ground foundation, easy to protect and convenient transportation, convenient for placing receiving equipment, and a wide field of view. The height angle of surrounding obstacles in the field of view should generally be less than 15°.

[0060] (2) It should be convenient for joint measurement and expansion with other measurement methods, and it is best to have line of sight with 1 to 2 adjacent points.

[0061] (3) The installation site should be at least 200m away from high-power radio transmission sources and at least 50m away from high-voltage transmission lines.

[0062] (4) There should be no objects that strongly reflect electromagnetic waves near the installation site, such as large areas of water, mirror-like buildings, etc.

[0063] In step S2, the following steps are specifically included:

[0064] S21: Dig a foundation pit from the ground to below the frozen soil layer at the installation site;

[0065] S22: lowering the frame template 31 and installing the anchor bolts 32 along the first direction F1;

[0066] S23: pouring concrete into the foundation pit to form a foundation 33.

[0067] First, dig from the ground to below the frozen soil layer at the selected installation location (rear view point); second, lower the 700mm*700mm frame formwork 31 and anchor bolts 32. When pouring concrete for the foundation, the anchor bolts 32 should be firm and accurately positioned. Use a spirit level to measure the horizontality and position of the embedded parts during pouring to ensure that the bolts are installed vertically and well protected; finally, after the concrete is poured, cover it with straw mats and sprinkle water for maintenance in time. The maintenance time is no less than 7 days.

[0068] In step S3, after the installation of the mounting member 3 is completed, the whole formed by the coarse aiming member 1 and the fine aiming member 2 is installed on the embedded frame template 31, and the verticality of the coarse aiming member 1 and the fine aiming member 2 is checked using a level, and they are installed firmly.

[0069] In step S4: use one end of the measuring line to fix it to 10cm above the bottom of the steel pipe, take the coarse aiming piece 1 as the axis, use the other end of the measuring line with the same length to take at least three points on the ground, use RTK and a tripod to accurately measure the three-dimensional coordinates of the point positions (use a smoothing method to measure at least three times to get the average value), project the measured coordinates onto the CAD software, and use the CAD software three-point determination of the center of the circle method to find the axis coordinates of the steel pipe. According to actual needs, use the above method to make 3-5 rear-sight orientation points, and directly enter the coordinates of the rear-sight points during use.

[0070] In the above embodiments, the rear-view orientation device and orientation method used with the three-dimensional laser scanner provide safety protection and improve work efficiency for fixed surveying and mapping areas in open-pit mines or large-area terrain surveys, and can effectively avoid precision errors in rear-view positioning points caused by frequent manual intervention. At the same time, the three-point center-of-circle method and steel pipes of different diameters can provide options for distance measurement, breaking through the traditional rear-view observation mode of the three-dimensional laser scanner.

[0071] The technical features of the above-described embodiments may be arbitrarily combined. To make the description concise, not all possible combinations of the technical features in the above-described embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0072] The above-described embodiments only express several implementation methods of the present application, and the descriptions thereof are relatively specific and detailed, but they cannot be construed as limiting the scope of the patent application. It should be pointed out that, for a person of ordinary skill in the art, several variations and improvements can be made without departing from the concept of the present application, and these all belong to the protection scope of the present application. Therefore, the protection scope of the patent application shall be subject to the attached claims.

Claims

1. A rear-view orientation device, characterized in that: include: A coarse aiming member extends along a first direction, and a plurality of coarse aiming spacing areas and coarse aiming marking areas are formed on a surface of the coarse aiming member along the first direction, wherein the coarse aiming spacing areas and the coarse aiming marking areas are arranged one by one; A fine aiming member extending along the first direction and fixed to one end of the coarse aiming member, wherein a plurality of fine aiming spacing areas and fine aiming marking areas are formed on the surface of the fine aiming member, wherein the fine aiming spacing areas and the fine aiming marking areas are arranged one by one; and A mounting member connected to one end of the coarse aiming member away from the fine aiming member, the mounting member being used to fix the coarse aiming member and the fine aiming member to the ground; Wherein, along the first direction, the projection area of ​​the coarse aiming component on the first reference plane is larger than the projection area of ​​the fine aiming component on the first reference plane, and the first direction is perpendicular to the first reference plane.

2. The rear-view orientation device according to claim 1, characterized in that: In the first direction, the total length of the coarse aiming piece and the fine aiming piece is greater than or equal to 5 m.

3. The rear-view orientation device according to claim 1, characterized in that: In the first direction, the size of the coarse aiming component is greater than the size of the fine aiming component.

4. The rear-view orientation device according to claim 1, characterized in that: In a second direction, a size of the coarse aiming component is greater than a size of the fine aiming component, and the second direction is perpendicular to the first direction.

5. The rear-view orientation device according to claim 1, characterized in that: In the first direction, the central axis of the fine aiming member coincides with the central axis of the coarse aiming member.

6. The rear-view orientation device according to claim 1, characterized in that: The mounting member comprises a frame template and anchor bolts. The frame template is connected to one end of the coarse aiming member away from the fine aiming member. The anchor bolts are passed through the frame template along the first direction and fixed to the ground.

7. The rearward-looking orientation device according to claim 6, characterized in that: The mounting member further comprises a base, the anchor bolts are buried in the base, and the base can be buried below the ground.

8. The rear-view orientation device according to claim 1, characterized in that: The rearward-looking orientation device further comprises a measuring line, which is rotatably connected to the coarse aiming component and is configured to be rotatable around a central axis of the coarse aiming component.

9. A method for orientation, characterized in that: The rear-view orientation device according to any one of claims 1 to 8 is applied, and the orientation method comprises: Select the installation location; Dig a foundation pit and embed the installation parts to provide an installation foundation; Install the coarse aiming parts and the fine aiming parts in sequence; Determine the axis coordinates of the rear-view orientation device.

10. The orientation method according to claim 9, characterized in that: The excavation of the foundation pit and pre-embedding of the installation parts to provide the installation foundation comprises: Dig a foundation pit from the ground to below the permafrost layer at the installation site; Lowering the frame formwork and inserting anchor bolts along the first direction; Concrete is poured into the pit to form the foundation.

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