JP2023074662A - Surveying-purpose device, and surveying method - Google Patents

Abstract

To solve the problems in which conventional arts get involved, that is, to provide a surveying-purpose device that uses an external corner or internal corner not only as a surveying reference point, but also as a level reference point (a bench mark), and to provide a surveying method that uses the surveying-purpose device.SOLUTION: A surveying-purpose device according to the present invention comprises: a ruler plate that is made of an L-shaped plate in a plan view; and a supporting cylinder that is installed in a top surface of the ruler plate. The supporting cylinder is arranged almost vertically to the ruler plate. Then, an inner side L-shaped line or an exterior side L-shaped line abuts against an almost vertically intersecting exterior corner or internal corner, and in turn the ruler plate is almost horizontally arranged. In a state with the ruler plate almost horizontally arranged, when inserting a pin of a surveying-purpose reflection prism into an insertion hole, the surveying-purpose reflection prism is arranged almost vertically, and a lower end of the pin abuts against the top surface.SELECTED DRAWING: Figure 1

Description

The present invention relates particularly to a device used for indoor surveying, and more specifically to a surveying device that can be installed at an external corner or an internal corner, and a surveying method using the same.

BACKGROUND ART When constructing a building such as a distribution warehouse or a factory, floor concrete leveling (hereinafter referred to as "floor leveling") is carried out when floor concrete is completely poured. Conventionally, when performing this floor level survey, a plane coordinate survey is performed using the standard lines provided on the floor, and leveling is performed using the black ink provided on the pillars. It was the mainstream to implement.

Normally, the plane coordinates (X, Y) of the vertices (that is, the outward corners) of the pillars in a plan view are known. etc.) can be set, that is, a plane coordinate system (generally an arbitrary coordinate system) can be set on the floor surface. Further, by setting a plurality of reference blacks that intersect in a grid pattern, the plane coordinates of the intersections of the reference blacks can be obtained from various conditions (intervals of the reference blacks, amount of escape from the cylinder surface, etc.). Then, after sighting a point with a known height (that is, a benchmark) such as black and white with a spirit level (for example, an auto level), aim a box scale (staff) installed at the intersection of the reference ink and Measure the height of the position.

In this way, in conventional floor level surveying, the plane coordinates are determined by setting the standard black, and then the height is repeatedly obtained for each intersection of the standard black using the auto level. In other words, a two-step process is required, one for grasping the plane coordinates and the other for determining the height of that position, and at least two workers are required: one in charge of the level and the other in charge of the staff. Met. Also, even in the case where it is necessary to obtain the plane coordinates of an arbitrary point that is not the intersection of the reference inks, there are two people: the person in charge of the surveying equipment such as the total station and transit, and the person who installs the reflection prism (so-called target) for surveying at the measurement point. I had to keep people. On the other hand, the results of the floor level survey (that is, the plane coordinates and height) are recorded in drawings and field notebooks by the surveyor on the spot, and the survey results are displayed on the CAD (Computer Aided Design). When the operator wanted to do so, the operator had to re-enter the numerical values recorded on the drawing or the like (so-called manual input).

As mentioned above, the conventional floor level survey requires two processes, which is time-consuming and troublesome, and at least two workers must be secured. rice field. Furthermore, the work of recording survey results and manually inputting them into CAD data is both time-consuming and error-prone, especially in cases where the floor area is large. rice field.

By the way, it has been explained that the plane coordinates of the protruding corners of the pillars are usually known. Therefore, if the projecting corner of the pillar is used as the survey reference point, the plane coordinates of an arbitrary measurement point can be obtained. Specifically, by installing a surveying instrument such as a total station or a transit and collimating the protruding corners of two pillars, the installation coordinates of the surveying instrument can be obtained, and as a result, the coordinates of any measurement point can be obtained. It is possible.

However, when the external corner of the pillar is used as a survey reference point, the survey reflecting prism must be placed at the external corner in a predetermined posture (for example, the pin is vertical), but the survey reflecting prism itself becomes an obstacle. I can't arrange it as I want. There have been various proposals for techniques that use the outside corner of a pillar as a survey reference point. A spaced surveying device is proposed.

Japanese Unexamined Patent Application Publication No. 2004-053328

According to the technique disclosed in Patent Literature 1, it is possible to measure the planar coordinates of the corner of the pillar, or to use the corner of the pillar as the survey reference point. However, since two or more survey reflecting prisms are used, manufacturing costs are high, and since these survey reflecting prisms are permanently installed, collimation by automatic tracking is difficult. In addition, the surveying device of Patent Document 1 needs to maintain a horizontal posture while checking the level, which requires manpower, and the posture becomes unstable, so there is a problem that the surveying accuracy is not stable. be. Furthermore, although the plane coordinates can be obtained, the height cannot be grasped, and the problem of the conventional floor level survey cannot be solved in that it is necessary to perform the level survey again.

The object of the present invention is to solve the problems of the prior art, that is, to use an external corner or an internal corner as a survey reference point, and to use it as a level reference point (benchmark). It is to provide a device and a surveying method using the same.

The invention of the present application has been made by paying attention to the point that the horizontal posture is automatically maintained by arranging L-shaped plate materials at the external corners and internal corners, and is based on an unprecedented idea. It is an invention made by

A surveying device according to the present invention includes a ruler plate made of an L-shaped plate material when viewed from above, and a support cylinder installed on the upper surface of the ruler plate. An inner L-shaped line consisting of two substantially vertical (including vertical) lines is formed inside the ruler plate, and an inner L-shaped line consisting of two substantially vertical (including vertical) lines is formed outside the ruler plate. An outer L-shaped line is formed. Further, the support tube is arranged substantially perpendicularly (including perpendicularly) to the ruler plate, and an insertion hole is formed therein so as to pass through the support tube. Then, when the inner L-shaped line is brought into contact with the outside corner that intersects approximately vertically (including perpendicularly), or the outer L-shaped line is brought into contact with the inside corner that intersects approximately vertically (including vertically), the ruler plate is When the reflecting prism for surveying is placed substantially horizontally (including horizontal) and the pin of the reflecting prism for surveying is inserted into the insertion hole in this state, the reflecting prism for surveying is placed substantially vertically (including vertically), and the lower end of the pin is It abuts on the upper surface of the ruler plate.

The surveying device of the present invention can also be configured such that two or more support cylinders are installed on the upper surface of the ruler plate.

The surveying device of the present invention can also be one in which a bubble level is provided on the upper surface of the ruler plate.

The surveying device of the present invention may further include a wall plate. This wall plate is arranged substantially vertically (including vertical) with respect to the ruler plate, and is attached to the inner L-shaped line of the ruler plate. In this case, when the inner L-shaped line abuts against a pillar having protruding corners crossing substantially vertically (including perpendicularly), the wall plate abuts against the wall surface of the pillar.

A surveying method according to the present invention is a method for obtaining coordinates of an arbitrary point using a surveying device according to the present invention, and includes a first placement step, a first collimation step, a second placement step, and a second collimation step. , an installation position calculation step, and a coordinate acquisition step. Among these, in the first placement step, the inner L-shaped line of the surveying device is placed at the first outside corner that intersects substantially vertically (including vertical), or the outer L-shaped line of the surveying device is placed substantially vertically (including vertical). ), and place the surveying instrument so that it abuts the first inside corner that intersects the . In the first collimation step, the pin of the reflecting prism for surveying is inserted into the insertion hole while the ruler plate is in contact with the first external corner (or the first internal corner), and the reflection for surveying by the surveying instrument is inserted. Aim the prism. Similarly, in the second placement step, a second outside corner that intersects the inner L-shaped line of the surveying instrument substantially vertically (including vertical) (or the outer L-shaped line of the surveying instrument is positioned substantially vertically (including vertical) ), and in the second collimation step, the ruler plate is brought into contact with the second external corner (or the second internal corner) In this state, the pin of the reflecting prism for surveying is inserted into the insertion hole, and the reflecting prism for surveying is collimated by the surveying instrument. In the installation position calculation step, the coordinates of the installation position of the surveying device are calculated based on the measurement results obtained in the first collimation step and the second collimation step. In the coordinate acquisition step, the reflecting prism for surveying is arranged at an arbitrary measuring point, and the coordinates of the measuring point are acquired by collimating the reflecting prism for surveying with a surveying instrument. When the ruler plate is brought into contact with the first external corner (or the first internal corner), the center coordinates of the insertion hole are known, and the ruler plate is applied with the second external corner (or the second internal corner). The central coordinates of the insertion hole are known when they are in contact.

The surveying device and surveying method of the present invention have the following effects.
(1) The reference plane coordinates and the reference height can be obtained by collimating the surveying instrument once, and as a result, floor level surveying can be performed more efficiently than before.
(2) By just touching the inner L-shaped line or outer L-shaped line to the external or internal corner, the almost horizontal (including horizontal) posture of the ruler board is stably maintained, resulting in stable and accurate survey results. can be obtained.
(3) By using a surveying instrument, there is no need to record survey results on drawings or the like at the site, and CAD data can be automatically generated without manual input.
(4) Furthermore, by using an automatic tracking type surveying instrument, even a single operator can perform floor level surveying.

BRIEF DESCRIPTION OF THE DRAWINGS The perspective view which shows typically the apparatus for surveying of this invention. (a) is a plan view of the surveying device viewed from above, and (b) is a side view of the surveying device viewed from the side. FIG. 4 is a side view schematically showing a surveying device that supports a surveying reflection prism in contact with a pillar; A perspective view schematically showing a surveying instrument arranged so that the inner L-shaped line of the ruler plate abuts the protruding corner. FIG. 4 is a perspective view schematically showing a surveying instrument arranged so that an outer L-shaped line of a ruler plate abuts an inside corner; FIG. 4 is a plan view schematically showing a ruler board on which markers are installed; FIG. 2 is a plan view for explaining an example of performing surveying by arranging the surveying device 100 at the protruding corner of a pillar. The flowchart which shows the main processes of the surveying method of this invention.

An embodiment of a surveying device and a surveying method according to the present invention will be described with reference to the drawings.

1. Surveying Device First, the surveying device of the present invention will be described in detail. Note that the surveying method of the present invention is a method of mainly performing indoor surveying using the surveying device of the present invention. Therefore, first, the surveying device of the present invention will be described, and then the surveying method of the present invention will be described.

FIG. 1 is a perspective view schematically showing a surveying device 100 of the present invention. As shown in this figure, the surveying device 100 of the present invention includes a ruler plate 110 and a support tube 120, and may also include a wall plate 130 and a level 140. FIG.

The ruler plate 110 is L-shaped in plan view as shown in FIG. 2(a), and is a thin plate-like member as shown in FIG. 2(b). 2(a) is a plan view of the surveying device 100 viewed from above, and FIG. 2(b) is a side view of the surveying device 100 viewed from the side. An inner L-shaped line IL consisting of two substantially vertical (including vertical) line segments is formed inside the ruler plate 110 (on the upper left side in the figure), and outside it (on the lower right side in the figure), An outer L-shaped line OL consisting of two substantially vertical (including vertical) line segments is formed.

The support tube 120, as shown in FIG. 3, supports the survey reflecting prism PR, and is a member including a body portion 121 (FIG. 1) and an insertion hole 122 (FIG. 1) provided in the center thereof. FIG. 3 is a side view schematically showing the surveying device 100 supporting the surveying reflection prism PR in contact with the pillar. The support cylinder 120 is installed on the upper surface of the ruler plate 110 so that the insertion hole 122 is substantially perpendicular (including perpendicular) to the ruler plate 110 . The insertion hole 122 extends through the entire length of the main body 121 , so that when the pin of the reflecting prism PR for surveying is inserted through the insertion hole 122 , the lower end of the pin is grounded on the upper surface of the ruler plate 110 . .

The support cylinder 120 needs to be installed only at one place on the ruler plate 110, but depending on the location, the support cylinder 120 (that is, the survey reflecting prism PR) may be positioned at a position where it is difficult for the surveying instrument to collimate. There is also Therefore, the support cylinders 120 can be installed at two or more locations on the ruler plate 110 in order to increase the options for installing the survey reflecting prism PR.

As shown in FIGS. 1 and 2B, the wall plate 130 is positioned on the inner L-shaped line IL on the lower surface side of the ruler plate 110 so as to be substantially perpendicular (including perpendicular) to the ruler plate 110. It is a plate-like member that is attached along. The wall plate 130 can also be attached to the ruler plate 110 over the entire length of the inner L-shaped line IL (that is, with an extension equivalent to the length of the inner L-shaped line IL), or form the inner L-shaped line IL. It is also possible to partially attach each of the two line segments. Further, the wall plate 130 can be fixed to the ruler plate 110 so as not to be removable, or the wall plate 130 can be attached to the ruler plate 110 so as to be detachable. Further, instead of (or in addition to) the inner L-shaped line IL, the wall plate 130 can be attached along the outer L-shaped line OL.

The surveying device 100 is arranged so that the inner L-shaped line IL of the ruler plate 110 abuts on the outer corner as shown in FIG. It is used by arranging it so as to abut on the corner. For example, as shown in FIG. 3, the wall plate 130 (that is, the inner L-shaped line IL) is applied to the outside corner of the pillar where two substantially vertical planes (including vertical planes) intersect substantially vertically (including vertical planes). When brought into contact, the ruler plate 110 becomes substantially horizontal (including horizontal), and the insertion hole 122 of the support tube 120 becomes substantially vertical (including vertical). As a result, the reflecting prism PR for surveying whose pin is inserted through the insertion hole 122 becomes substantially vertical (including vertical), that is, the reflecting prism PR for surveying can indicate the planar position (X, Y) of the lower end of the pin. . Also, if the surveying device 100 is arranged so that the upper surface of the ruler plate 110 is the black ink provided on the pillar (for example, the black ink 1 m higher than the floor surface), the reflecting prism PR for surveying is landed by the lower end of the pin. Ink height (Z) can be indicated.

By the way, when the wall plate 130 arranged substantially vertically (including vertical) is brought into contact with an external corner or an internal corner where two substantially vertical wall surfaces (including vertical wall surfaces) intersect substantially vertically (including vertical), The wall plate 130 has a substantially vertical surface (including a vertical surface), and the ruler plate 110 has a substantially horizontal surface (including a horizontal surface). That is, when two vertically intersecting fixed surfaces are brought into contact with two vertically intersecting movable surfaces, the attitudes of these movable surfaces are defined by the fixed surfaces. For example, if the fixed surfaces are vertical, the movable surfaces are also vertical. On the other hand, when two perpendicularly intersecting line segments are brought into contact with two perpendicularly intersecting fixed planes, the postures of these line segments are not defined by the fixed planes. In other words, the posture of the ruler plate 110 cannot be determined simply by abutting on two fixed surfaces that vertically intersect the inner L-shaped line IL and the outer L-shaped line OL. However, since the ruler plate 110 is a plate material, a wall surface (hereinafter referred to as a "thick surface") is formed in the thickness direction, and normally this thick surface and the upper or lower surface of the plate material are substantially perpendicular (perpendicular). including). Therefore, even if the wall plate 130 is omitted, if the inner L-shaped line IL is placed so as to abut on the outer corner (or the outer L-shaped line OL is placed at the inner corner), the ruler plate 110 is substantially horizontal. ), and the insertion hole 122 of the support tube 120 is substantially vertical (including vertical).

As described above, the ruler plate 110 is substantially horizontal (including horizontal) when the inner L-shaped line IL is arranged to abut on the outer corner (or the outer L-shaped line OL is positioned on the inner corner). However, the operator who arranges the surveying device 100 may want to confirm that the ruler plate 110 is substantially horizontal (including horizontal). In this case, as shown in FIGS. 1 and 2, it is preferable to provide a bubble level 140 on the upper surface of the ruler plate 110 .

The support cylinder 120 can support the reflecting prism PR for surveying, that is, it is not necessary to secure an operator holding the reflecting prism PR for surveying, and it is possible to save labor. On the other hand, the provision of the support tube 120 makes the entire surveying device 100 larger, making it somewhat difficult to handle and store. Therefore, as shown in FIG. 6, the marker 150 can be installed on the ruler plate 110 and the support tube 120 can be omitted. In this case, since the surveying reflection prism PR is set at the position of the marker 150 so that the worker takes a vertical posture, it is necessary to secure the worker, but the surveying device 100 can be made compact and manufactured. Costs can also be reduced. Of course, like the support tube 120, the marker 150 can be provided at only one location, or can be provided at two or more locations.

An example of using the surveying device 100 will be described below with reference to FIG. FIG. 7 is a plan view for explaining an example in which the surveying device 100 is placed at the protruding corner of a pillar for surveying. Normally, when performing indoor surveying such as floor level surveying, planar coordinates (mostly arbitrary coordinate systems) are set in the room. At this time, as shown in FIG. 7, it is common to set orthogonal two axes (X-axis and Y-axis) along the wall surface forming the pillar. Further, the plane coordinates of the projected corners of the pillars are known, that is, they can be used as plane reference points. Furthermore, the height of the black ink provided on the pillar (for example, black ink that is 1 m higher than the floor surface) is known, that is, it can be used as an elevation reference point (benchmark).

On the other hand, the center point of the insertion hole 122 of the ruler plate 110 and the center point of the marker 150 (that is, the planar position indicated by the reflecting prism PR for surveying) are based on the corner of the inner L-shaped line IL (connecting point of two lines). and the position based on the corner of the outer L-shaped line OL are grasped in advance. Therefore, the ruler plate 110 is placed so that the inner L-shaped line IL abuts the outer corner (or the outer L-shaped line OL abuts the inner corner), and then the survey reflecting prism PR is inserted through the insertion hole 122. Then (or when it is set at the position of the marker 150), the positional relationship between the planar position of the reflecting prism PR for surveying and the planar position of the protruding corner of the pillar becomes clear. For example, in FIG. 7, the plane coordinates of the protruding corner of the pillar are (X1, Y1), and the center point of the insertion hole 122 is separated from the corner of the inner L-shaped line IL by (δX, δY). The plane position indicated by the reflecting prism PR is (X1-.delta.X, Y1-.delta.Y). Thus, by using the surveying device 100, the position of the reflecting prism PR for surveying can be used as a plane reference point, and the height of the reflecting prism PR for surveying can be determined by aligning the ruler plate 110 and the black ink. can be used as a benchmark.

2. Surveying Method Next, the surveying method of the present invention will be described with reference to FIG. It should be noted that the surveying method of the present invention is a method of mainly performing indoor surveying using the surveying device 100 described so far. Only the content specific to the survey method will be explained. That is, the contents not described here are the same as those described in "1. Surveying device".

FIG. 8 is a flowchart showing main steps of the surveying method of the present invention. As shown in this figure, the surveying method of the present invention can be broadly divided into a "preliminary process" and a "measurement process" enclosed by broken lines. Among these processes, the preliminary process is a process of determining the position where a surveying instrument such as a total station is installed. The pre-process will be described in detail below.

First, an operator installs a surveying instrument at a desired position. Then, the operator places the surveying device 100 at the first external corner (or the first internal corner) and inserts the surveying reflecting prism PR into the insertion hole 122 (Step 211). At this time, as described above, the surveying device 100 is arranged so that the inner L-shaped line IL abuts the outside corner (or so that the outside L-shaped line OL abuts the inside corner). When the surveying device 100 is placed at the first outside corner (or the first inside corner), the surveying reflecting prism PR is collimated by the surveying instrument (Step 212). It should be noted that the survey can be carried out by two workers, one is the operator who sights the surveying instrument and the other is the operator who maintains the surveying device 100 as it is placed. Surveying can also be carried out by workers of After the same worker installs the surveying devices 100, the surveying devices 100 are placed one by one, that is, the surveying work is performed independently.

When collimating the survey reflecting prism PR set at the first external corner (or first internal corner), the operator places the surveying device 100 at the second external corner (or second internal corner). At the same time, the survey reflecting prism PR is inserted through the insertion hole 122 (Step 213). Then, when the surveying device 100 is placed at the second outside corner (or second inside corner), the surveying reflecting prism PR is collimated by the surveying instrument (Step 214). The first collimation step (Step 212) obtains the angle (azimuth angle) and distance between the installation position of the surveying instrument and the first outside corner (or first inside corner). Step 214) obtains the angle (azimuth) and the distance between the installation position of the surveying instrument and the second external corner (or second internal corner). Thereby, the installation position of the surveying instrument can be calculated (Step 215). Also, at either (or both) of the first external corner (or first internal corner) or the second external corner (or second internal corner), the upper surface of the ruler plate 110 and the black ink of the pillar are aligned. Then, if the surveying device 100 is arranged, the installation height of the surveying instrument can be grasped.

As described above, when the pre-process is completed, the measurement process is subsequently performed. Specifically, after the operator installs the reflecting prism PR for surveying at a desired measurement point, the reflecting prism PR for surveying is collimated by the surveying instrument (Step 221). At this time, without using the surveying device 100, the operator normally installs the reflecting prism PR for surveying. Then, using the result of collimation of the surveying reflecting prism PR by the surveying instrument, the plane coordinates and height of the measurement point are calculated (Step 222). By repeating this arbitrary point collimation step (Step 221), the plane coordinates and heights of a plurality of measurement points can be obtained.

INDUSTRIAL APPLICABILITY The surveying device and surveying method of the present invention can be used for surveying various buildings (in particular, indoor surveying) having outside corners and inside corners such as distribution warehouses and factories. In addition to floor level surveying, it can also be used to survey the plane positions and heights of various facilities.

100 Surveying device of the present invention 110 Ruler plate (of surveying device) 120 Support cylinder (of surveying device) 121 Main body (of support cylinder) 122 Insertion hole (of support cylinder) 130 Wall plate (of surveying device) 140 Level (of surveying device) 150 Marker (of surveying device) IL Inside L-shaped line (of surveying device) OL Outer L-shaped line (of surveying device) PR Survey reflecting prism

Claims (5)

a ruler plate made of a plate material having an L shape when viewed from above;
a support cylinder installed on the upper surface of the ruler plate,
An inner L-shaped line consisting of two vertical or substantially vertical line segments is formed on the inner side of the ruler plate, and an outer L-shaped line consisting of two vertical or substantially vertical line segments is formed on the outer side of the ruler plate. character lines are formed,
The support cylinder is arranged perpendicularly or substantially perpendicularly to the ruler plate, and is formed with an insertion hole penetrating through the support cylinder,
When the inner L-shaped line comes into contact with an external corner that intersects vertically or approximately vertically, or the outer L-shaped line comes into contact with an internal corner that intersects vertically or approximately vertically, the ruler plate is horizontal or approximately horizontal. placed and
When the pin of the reflecting prism for surveying is inserted into the insertion hole in a state in which the ruler plate is arranged horizontally or substantially horizontally, the reflecting prism for surveying is arranged vertically or substantially vertically, and the reflecting prism for surveying is arranged vertically or substantially vertically. the lower end of the pin of the reflecting prism abuts the upper surface of the ruler plate;
A surveying device characterized by: Two or more of the support cylinders are installed on the upper surface of the ruler plate,
The surveying device according to claim 1, characterized in that: A bubble level is provided on the upper surface of the ruler plate,
3. A surveying device according to claim 1 or 2, characterized in that: further comprising a wall plate arranged perpendicularly or substantially perpendicularly to the ruler plate and attached to the inner L-shaped line of the ruler plate,
When the inner L-shaped line abuts against a pillar having an outward corner that intersects vertically or substantially vertically, the wall plate abuts against the wall surface of the pillar.
The surveying device according to any one of claims 1 to 3, characterized in that: A method for obtaining coordinates of an arbitrary point using the surveying device according to any one of claims 1 to 4,
At a first outside corner that vertically or substantially vertically intersects the inner L-shaped line of the surveying instrument, or at a first input that vertically or substantially vertically intersects the outer L-shaped line of the surveying instrument. a first arranging step of arranging the surveying device so as to abut on a corner;
With the ruler plate in contact with the first external corner or the first internal corner, the pin of the reflecting prism for surveying is inserted into the insertion hole, and the reflecting prism for surveying is moved by a surveying instrument. a first collimation step of collimating;
at a second outgoing corner that vertically or substantially vertically intersects the inner L-shaped line of the surveying instrument, or a second input that vertically or substantially vertically intersects the outer L-shaped line of the surveying instrument; a second arranging step of arranging the surveying device so as to abut on a corner;
With the ruler plate in contact with the second external corner or the second internal corner, the pin of the reflecting prism for surveying is inserted into the insertion hole, and the reflecting prism for surveying is moved by the surveying instrument. a second collimation step of collimating the
an installation position calculation step of calculating the coordinates of the installation position of the surveying device based on the measurement result obtained in the first collimation step and the measurement result obtained in the second collimation step;
a coordinate acquisition step of arranging the reflecting prism for surveying at an arbitrary measuring point and collimating the reflecting prism for surveying by the surveying instrument to acquire the coordinates of the measuring point;
When the ruler plate is brought into contact with the first external corner or the first internal corner, the center coordinates of the insertion hole are known, and the ruler is positioned at the second external corner or the second internal corner. When the plate is brought into contact with the plate, the center coordinates of the through hole are known.
A surveying method characterized by:

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