Position measurement method

Abstract

To perform accurate position measurement using simple procedures. [Solution] The present disclosure relates to a position measurement method for measuring the position of a cylindrical measurement object placed on a wall. In this method, at least three measurement tools having target markers are installed at different positions on the measurement surface side of the measurement object, with the target markers facing the measurement surface. Then, imaging data is obtained by photographing the measurement object together with the reference surface of the measurement object and the at least three measurement tools.

Description

[Technical field]

[0001] The present disclosure relates to a position measuring method and a measuring tool. [Background technology]

[0002] Embedded materials such as pipes and metal parts are often installed in the walls, floors, ceilings, etc. of buildings for various purposes. For example, when constructing a reinforced concrete building, these embedded materials are installed in pre-designed positions before concrete is placed on the reinforcing bars that form the foundation and run along the planes of the walls, floors, ceilings, etc. Conventionally, the installation positions of embedded materials were confirmed and inspected by workers measuring them manually, but the measurement results were easily affected by the skill of the workers, making it difficult to obtain good accuracy.

[0003] As a tool for improving the measurement accuracy when such an embedded member is used as the measurement target, a device capable of measuring the position of the measurement target by photographing the measurement target with a camera and analyzing the image is known. For example, Patent Document 1 discloses a technology in which the measurement target is not an embedded member, but based on an image photographed with a line camera from a different direction or position, the position of a measurement point included in the image is measured. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2006-258486 A Summary of the Invention [Problem to be solved by the invention]

[0005] In the above Patent Document 1, the positions of measurement points included in an image are measured based on images taken from different directions or positions using a line camera. This requires a dedicated line camera to be prepared, and also requires taking images from different directions or positions, which increases the cost and effort required for the measurement work.

[0006] At least one embodiment of the present disclosure has been made in consideration of the above-mentioned circumstances, and has an object to provide a position measurement method and a measurement tool that enable accurate position measurement with a simple procedure. [Means for solving the problem]

[0007] In order to solve the above problem, a position measurement method according to at least one embodiment of the present disclosure includes: 1. A position measurement method for measuring a position of a cylindrical measurement object disposed on a wall portion, comprising: a step of placing at least three measurement jigs having target markers at different positions on a measurement surface side of the measurement object such that the target markers face the measurement surface; acquiring imaging data by photographing the measurement object together with a reference surface of the measurement object and the at least three measurement tools; Equipped with.

[0008] In order to solve the above problems, a measuring jig according to at least one embodiment of the present disclosure includes: A measurement tool used to measure a position of a cylindrical measurement object disposed on a wall portion, comprising: a main body having a first surface on which a target marker is provided, and a second surface facing the measurement object when the main body is placed on the measurement object so that the target marker faces the measurement surface; a flange portion extending from the main body along the measurement surface and forming a step portion between the flange portion and the second surface; a fixing portion for detachably fixing the main body to the measurement object; Equipped with. Effect of the Invention

[0009] According to at least one embodiment of the present disclosure, it is possible to provide a position measuring method and a measuring tool that enable accurate position measurement with a simple procedure. [Brief description of the drawings]

[0010] [Figure 1] 1 is a schematic diagram showing a measurement object of a position measuring method according to an embodiment; [Diagram 2] FIG. 1 is a perspective view showing a measuring jig according to an embodiment. [Diagram 3] 4 is a flowchart illustrating a position measuring method according to an embodiment. [Figure 4] 13 is an example of setting a measurement jig for a measurement object having a substantially circular cross section. [Diagram 5] 13 is an example of setting a measurement jig for a measurement object having a substantially rectangular cross section. [Figure 6] 4 is a schematic diagram showing a method of calculating a second center position in step S6 of FIG. 3. FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0011] Hereinafter, some embodiments of the present invention will be described with reference to the accompanying drawings. However, the configurations described as the embodiments or shown in the drawings are merely illustrative examples and are not intended to limit the scope of the present invention.

[0012] First, a measurement object 10 for a position measuring method according to at least one embodiment of the present disclosure will be described with reference to Fig. 1. Fig. 1 is a schematic diagram showing a measurement object 10 for a position measuring method according to one embodiment.

[0013] The measurement object 10 is disposed on a wall 12 that at least partially divides the adjacent first and second spaces V1 and V2. The wall 12 extends along the XY plane and has a thickness t1 along the Z direction. In the following description, the side of the wall 12 facing the first space V1 is referred to as a first surface 12a, and the side facing the second space V2 is referred to as a second surface 12b.

[0014] 1 shows an example of the wall portion 12 dividing the first space V1 and the second space V2 adjacent to each other along the horizontal direction (Z direction), but the wall portion 12 may be a floor surface dividing the first space V1 and the second space V2 adjacent to each other in the vertical direction. At least one of the first space V1 and the second space V2 may be an indoor space or an outdoor space.

[0015] The measurement object 10 is an embedded member disposed so that at least a portion of it is embedded in the wall portion 12. In this embodiment, the measurement object 10 is a tubular member having a cylindrical shape, and is disposed with respect to the wall member 12 so that its central axis C is in the Z direction. The measurement object 10 has an axial length L and a thickness t2, and by setting the axial length L sufficiently larger than the thickness t2 of the wall portion 12, the measurement object 10 is disposed so that a first end 10A is exposed on the first space V1 side, and a second end 10B is exposed on the second space V2 side.

[0016] The measurement object 10 has a cylindrical shape including an internal space 14 inside. This cylindrical shape may have a bottom, but in this embodiment, the measurement object 10 is configured as a so-called through sleeve so that the first space V1 and the second space V2 penetrate through the internal space 14. Although not shown in FIG. 1, wiring including a power cable and a communication cable can be laid in the internal space 14 across the first space V1 and the second space V2.

[0017] The first end 10A and the second end 10B of the measurement object 10 both have end faces that are approximately perpendicular to the axial direction of the cylindrical shape. That is, as shown in Fig. 1, when the measurement object 10 is disposed on the wall 12 so that the axial direction of the measurement object 10 is the Z direction, each end face at the first end 10A and the second end 10B extends along the XY plane and is perpendicular to the Z direction.

[0018] Next, a description will be given of a measuring jig 20 used when measuring the measurement object 10 having the above configuration. Fig. 2 is a perspective view showing the measuring jig 20 according to one embodiment.

[0019] The measuring jig 20 includes a main body 22 on which a target marker 24 is provided. The target marker 24 is provided on a first surface 26 of the main body 22 that faces the measurement surface when the measuring jig 20 is attached to the measurement target 10 described above as described below. The target marker 24 is provided as an indication that can be distinguished from the surroundings when photographed, for example, by having at least one of a predetermined color, shape, reflectance, etc. In the present embodiment, as an example of the target marker 24, a sticker-like mark that is attached to the main body 2 as a substantially circular symbol mark is shown, but the form is not limited thereto.

[0020] The main body 22 has a second surface 28 that is substantially perpendicular to the first surface 26 on which the target marker 24 is provided. The second surface 28 is provided at a position that contacts the measurement object 10 when the measurement jig 20 is attached to the measurement object 10 so that the target marker 24 faces the measurement surface. The main body 22 is provided with a fixing portion 38 for fixing the measurement jig 20 to the measurement object 10 in a detachable manner. The measurement object 10 is made of a magnetic material such as metal, and the fixing portion 38 is configured as a magnet (e.g., a neodymium magnet) embedded in the main body 22. Thereby, when the second surface 28 is attached so as to contact the measurement object 10, the measurement jig 20 can be detachably fixed to the measurement object 10 by the fixing portion 38.

[0021] The main body 22 also has a first extension portion 34 and a second extension portion 36 that extend from the center portion where the target marker 24 is provided along a first direction a and a second direction b that intersect with each other. In this embodiment, the first extension portion 34 and the second extension portion 36 intersect at an angle of approximately 90 degrees, but this intersecting angle may be any angle.

[0022] The outer side of the main body 22 (i.e., the obtuse angle side of the intersection angle between the first extension portion 34 and the second extension portion 36) has a flange portion 30 extending from the first surface 26. The flange portion 30 extends along a plane defined by the first direction a and the second direction b, similar to the first surface 26, and forms a step portion 32 together with a second surface 28 perpendicular to the plane. When the measuring jig 20 is attached to the measuring object 10 so that the second surface 28 is in contact with the measuring object 10, the step portion 32 engages with an end of the measuring object 10, thereby stabilizing the posture of the measuring jig 20.

[0023] Incidentally, the above-mentioned fixing portions 38 are provided in plurality so as to be embedded in the first extending portion 34 and the second extending portion 36 of the main body 22, respectively, but the layout of the fixing portions 38 is not limited thereto.

[0024] Next, a description will be given of a position measuring method for measuring the position of the above-mentioned measurement target 20 using such a measuring jig 20. Fig. 3 is a flowchart showing a position measuring method according to one embodiment. In the following description, a case where position measurement is performed from the first space V1 side will be exemplified, but unless otherwise specified, the same applies to a case where position measurement is performed from the second space V2 side.

[0025] First, at least three measuring jigs 20 are placed on the measurement object 10 (step S1). These measuring jigs 20 are placed so that the target marker 24 faces the measurement surface with respect to the edge of the first end 10A on the first space V1 side of the cylindrical measurement object 10 (i.e., the first surface 26, which is a plane defined by the first direction a and the second direction b, of the measuring jig shown in FIG. 2 is placed so that it is parallel to the XY plane in FIG. 1). Each measuring jig 20 has the configuration described above with reference to FIG. 2, and is placed so that the step portion 32 engages with the edge of the first end 10A, so that the target marker 24 faces the first space V1 side.

[0026] Here, with reference to Figures 4 and 5, several examples of installation of the measuring jig 20 in step S1 in Figure 3 will be specifically described. Figure 4 shows an example of installation of the measuring jig 20 for a measurement object 10 having a substantially circular cross section, and Figure 5 shows an example of installation of the measuring jig 20 for a measurement object 10 having a substantially rectangular cross section.

[0027] In Fig. 4, four measuring jigs 20 are installed with respect to the first end 10A having a substantially circular end face. In particular, each measuring jig 20 is fixed to the inner circumferential surface of the first end 10A of the measurement object 10 by a magnet embedded in the main body 22 as a fixing portion 38 in an orientation in which the outer sides of the first extension portion 34 and the second extension portion 36 (i.e., the obtuse angle side of the intersection angle) face the inner circumferential surface of the measurement object 10. At this time, the orientation of each measuring jig 20 is stabilized by installing the step portion 32 so that it engages with the end face of the first end 10A.

[0028] 4 illustrates a case where the measuring jigs 20 are arranged at equal intervals from each other along the circumferential direction at the first end 10A of the measurement object 10, but at least some of them may be arranged at different intervals (preferably, the measuring jigs 20 are arranged evenly to the extent that there is no extreme bias in the positions of the measuring jigs 20 in the circumferential direction). Also, in FIG. 4, a case where a plurality of measuring jigs 20 are installed along the inner peripheral edge on the first end 10A side of the measurement object 10 is illustrated, but at least some of these measuring jigs 20 may be arranged along the outer peripheral edge.

[0029] In FIG. 5, four measuring jigs 20 are installed against a first end 10A having a substantially rectangular end face. In particular, each measuring jig 20 is fixed against the inner circumferential surface of the first end 10A of the measurement object 10 by a magnet embedded in the main body 22 as a fixing portion 38, in an orientation in which the outer sides of the first extension portion 34 and the second extension portion 36 (i.e., the obtuse angle side of the intersection angle) face the inner circumferential surface of the measurement object 10. At this time, the first extension portion 34 and the second extension portion 36 of the measuring jig 10 are arranged so as to be in contact along two adjacent sides that form corners of the substantially rectangular end face. At this time, each measuring jig 20 has a step portion 32 that engages with the end face of the first end 10A. The position is stabilized by being placed so as to match the sensor.

[0030] Returning to Fig. 3, the measurement object 10 on which the measuring jig 20 is placed is then photographed from one side together with the reference surface of the measurement object 10 (step S2). In this embodiment, the reference surface of the measurement object 10 is the first surface 12a of the wall portion 12 on which the measurement object 10 is placed, and the measurement object 10 is photographed so that the photographing range includes the measurement object 10 and at least a part of the reference surface (first surface 12a) from the side of the first space V1 on which the measuring jig 20 is placed. The photographed image includes the measurement object 10 as well as at least three position measuring jigs 20 placed on the measurement object 10.

[0031] In step S2, an imaging device such as a three-dimensional camera is used that can obtain image data that allows three-dimensional coordinates to be specified for each pixel of a captured image.

[0032] Next, imaging data is acquired for the image captured in step S2 (step S3), and the imaging data is subjected to image analysis (step S4). In step S4, the imaging data is analyzed to identify three-dimensional coordinates for the target markers 24 of each measuring jig 20 included in the image. The three-dimensional coordinates are identified as coordinates corresponding to the first coordinate system corresponding to the imaging data.

[0033] Next, the positions of the characteristic parts of the measurement object 10 are measured based on the position coordinates of each target marker 24 identified by the image analysis in step S4 (step S5). In step S5, the positions of the characteristic parts are geometrically calculated based on the position coordinates of each target marker 24 identified by the image analysis. The geometric calculation method used in step S5 is not limited.

[0034] The feature to be calculated in step S5 may be the first center position O1 at the first end. Here, with reference to Figs. 4 and 5, some specific examples of the geometric calculation method in step S5 will be described. For example, Fig. 4 shows the target markers 24 of the four measuring jigs 20 arranged at the first end 10A having a circular end face as described above, and shows a schematic diagram of how the first center position O1 is determined as the center of an approximate circle uniquely specified based on these target markers 24. Fig. 5 also shows a schematic diagram of how the measuring jigs 20 are arranged at the four corners of the rectangular end face as described above, and how the first center position O1 is specified as the point of intersection of two straight lines connecting two pairs of target markers 24 facing each other.

[0035] 5, similarly to FIG. 4, the first center position O1 may be specified based on an approximation circle that passes through each target marker 24.

[0036] Furthermore, the characteristic portion to be calculated in step S5 may be the second center position O2 in the second end portion 10B. In this case, the second center position O2 can be calculated using the above-mentioned first center position O1.

[0037] Fig. 6 is a schematic diagram showing a method of calculating the second center position O2 in step S5 in Fig. 3. The end face at the first end 10A can be identified based on at least three target markers 24 of the measuring jig 20. This end face can be identified based on three target markers 24, but by identifying the end face based on four target markers 24 as in this embodiment, the torsional component of the end face can also be evaluated, enabling more accurate measurement.

[0038] Next, a second center position C2 at the second end 10B is identified based on the end face at the first end 10A and the length L of the measurement object 10. Specifically, a position on a straight line L0 that is perpendicular to the end face at the first end 10A and passes through the first center position O1 and is separated from the first center position O1 by the length L is identified as the second center position O2.

[0039] Furthermore, the characteristic portion to be calculated in step S5 may be the inclination θ with respect to the measurement surface (first surface 12a) of the measurement object 10. For example, in FIG. 6, this inclination θ can be specified as the angle that a straight line L0 connecting the first center position O1 and the second center position O2 makes with the measurement surface (first surface 12a).

[0040] Next, the three-dimensional coordinates of the feature portion measured in step S5 in the first coordinate system are transformed into a second coordinate system (step S6). The second coordinate system is the XYZ coordinate system shown in FIG.

[0041] Next, evaluation is performed by comparing the position coordinates of the characteristic parts transformed in step S6 with an allowable range (step S7). The mounting layout of the measurement object 10 on the wall 12 is specified in advance by design information, etc. In step S7, the position coordinates of the characteristic parts transformed in step S6 are compared with an allowable error specified based on such design information, etc., to evaluate whether the measurement object is properly mounted on the wall 12 based on the design information.

[0042] Next, the various evaluation results are output (step S8). The evaluation result output in step S8 may include various information such as the position coordinates of the characteristic parts of the measurement object that have been coordinate-converted in step S6, in addition to the evaluation result in step S7.

[0043] As described above, according to each of the above embodiments, the measurement object 10 placed on the wall portion 12 has a cylindrical shape, and at least three measuring jigs 20 are respectively installed so that the target markers 24 face the measurement surface. These measuring jigs 20 are photographed together with the reference surface (first surface 12a) of the measurement object 10 and the measurement object 10, thereby acquiring imaging data. The imaging data acquired in this manner includes the target markers 24 of the at least three measuring jigs 20 placed on the measurement object 10, and by analyzing the imaging data, any position of the measurement object 10 placed on the wall portion can be suitably measured based on the positions of these target markers 24.

[0044] In addition, within the scope of the present disclosure, the components in the above-described embodiments may be replaced with well-known components as appropriate, and the above-described embodiments may be combined as appropriate.

[0045] The contents described in each of the above embodiments can be understood, for example, as follows.

[0046] (1) A position measurement method according to one aspect includes the steps of: 1. A position measurement method for measuring a position of a cylindrical measurement object disposed on a wall portion, comprising: a step of placing at least three measurement jigs having target markers at different positions on a measurement surface side of the measurement object such that the target markers face the measurement surface; acquiring imaging data by photographing the measurement object together with a reference surface of the measurement object and the at least three measurement tools; Equipped with.

[0047] According to the above aspect (1), the measurement object placed on the wall has a cylindrical shape, and at least three measuring jigs are respectively installed so that the target marker faces the measurement surface. These measuring jigs are photographed together with the reference surface of the measurement object and the measurement object, thereby acquiring imaging data. The imaging data thus acquired includes the target markers of the at least three measuring jigs installed on the measurement object, and by analyzing the imaging data, it is possible to suitably measure any position of the measurement object installed on the wall based on the positions of these target markers.

[0048] (2) In another embodiment, in the above embodiment (1), Identifying position coordinates of a feature of the measurement object in a first coordinate system based on the imaging data; determining a measurement result by transforming the position coordinates into a second coordinate system defined by the reference plane and a normal axis relative to the reference plane; It further comprises:

[0049] According to the above aspect (2), the position coordinates of the characteristic portion of the measurement object in the first coordinate system are identified based on the imaging data. The position coordinates thus identified can be used to suitably obtain the position of the measurement object relative to the reference plane by converting the first coordinate system in the imaging data into a second coordinate system defined by the reference plane and a perpendicular axis of the reference plane.

[0050] (3) In another embodiment, in the above embodiment (2), The method further includes the step of determining whether the measurement result is within an acceptable range.

[0051] According to the above aspect (3), by comparing the measurement results obtained as described above with an allowable range obtained based on, for example, design information of the measurement object, the arrangement of the measurement object with respect to the measurement object surface can be appropriately evaluated.

[0052] (4) In another embodiment, in the above embodiment (2), The characteristic portion includes a first center position of a first end face of the object to be measured on the measurement surface side.

[0053] According to the above aspect (4), it is possible to suitably measure the first center position of the first end face on the measurement surface side of the measurement object.

[0054] (5) In another embodiment, in the above embodiment (4), the measurement object is disposed so as to penetrate the wall portion, The characteristic portion includes the first center position and, based on design information of the measurement object, a second center position on a second end face of the measurement object that is on the opposite side to the first end face with respect to the wall portion.

[0055] According to the above aspect (5), it is possible to suitably measure the second center position of the measurement object disposed so as to penetrate the wall portion, based on the first center position and design information.

[0056] (6) In another embodiment, in the above embodiment (5), The characteristic portion includes an inclination of the measurement object relative to the wall portion, the inclination being specified by the first center position and the second center position.

[0057] According to the above aspect (6), the inclination of the measurement object with respect to the wall portion can be suitably measured based on the first center position and the second center position.

[0058] (7) In another embodiment, in any one of the above (1) to (6), The at least three measurement tools include four or more measurement tools.

[0059] According to the above aspect (7), by placing at least four or more measuring tools on the object to be measured, when uniquely identifying the plane on which the measuring tools are placed based on the target markers of these measuring tools, it is possible to take into account the torsion element for the plane, thereby enabling more accurate position measurement.

[0060] (8) In another embodiment, in any one of the above (1) to (7), The at least three measurement jigs are disposed on at least one of the inner periphery or the outer periphery of an end face of the object to be measured on the side of the measurement surface.

[0061] According to the above aspect (8), at least three measuring jigs are disposed on the inner or outer periphery of the end face of the cylindrical measurement object on the measurement surface side. With this, by positioning the target marker near the periphery of the end face on the measurement surface side, the end face can be precisely identified, and the position of the measurement object can be precisely measured.

[0062] (9) In another embodiment, in any one of the above (1) to (8), The measurement object has a cylindrical shape, The at least three measurement jigs are disposed at different positions along the periphery of the measurement object on the side of the measurement surface.

[0063] According to the above aspect (9), by placing at least three measurement jigs at different positions along the circumference of the measurement surface side of a cylindrical measurement object, the cylindrical measurement object can be suitably measured.

[0064] (10) In another embodiment, in any one of the above (1) to (8), The measurement object has a rectangular cylindrical shape, The at least three measurement jigs are disposed at at least some corners of an end face of the object to be measured that faces the measurement surface.

[0065] According to the above aspect (10), by placing the measurement jig on at least some corners of the end face of the object to be measured having a rectangular cylindrical shape, the object to be measured having a rectangular cylindrical shape can be suitably measured.

[0066] (11) A measuring jig according to one embodiment includes: A measurement tool used to measure a position of a cylindrical measurement object disposed on a wall portion, comprising: a main body having a first surface on which a target marker is provided, and a second surface facing the measurement object when the main body is placed on the measurement object so that the target marker faces the measurement surface; a flange portion extending from the main body along the measurement surface and forming a step portion between the flange portion and the second surface; a fixing portion for detachably fixing the main body to the measurement object; Equipped with.

[0067] According to the above aspect (11), the body of the measuring jig has a flange portion extending along the measurement surface from the first surface on which the target marker is provided, thereby forming a step portion between the body and the second surface facing the measurement object when the measuring jig is attached. As a result, by positioning the measuring jig so that the step portion engages with the periphery on the measurement surface side of the measurement object, it becomes possible to preferably acquire the above-mentioned imaging data by photographing while stably maintaining the posture of the measuring jig attached to the measurement object.

[0068] (12) In another embodiment, in the above embodiment (11), The main body has a first extension portion and a second extension portion extending from a central portion where the target marker is provided along a first direction and a second direction that intersect with each other, The flange portion is provided along an edge portion of the main body on the side where the intersection angle between the first extension portion and the second extension portion is obtuse.

[0069] According to the above aspect (12), the flange portion which forms the step portion together with the second surface is provided such that the intersection angle between the first extension portion and the second extension portion of the main body is on the obtuse side. As a result, when the measuring jig is disposed so that the step portion engages with the periphery of the measurement object, the flange portion is appropriately fitted to the periphery of the measurement object, and the posture of the measuring jig can be stably maintained.

[0070] (13) In another embodiment, in the above embodiment (11) or (12), The fixed portion is at least one magnet embedded in the body portion.

[0071] According to the above aspect (13), by using a magnet embedded in the main body as the fixing part, the measurement jig can be detachably fixed to the measurement object. This makes it possible to easily attach and detach the measurement jig to the measurement object, while stably fixing the position of the target marker during measurement, thereby enabling accurate position measurement. [Explanation of symbols]

[0072] 10 Measurement Object 10A 1st end 10B 2nd end 12 Wall 12a 1st surface (measurement surface) 12b Side 2 14 Interior Space 20 Measuring fixture 22 Main unit 24 Target Marker 26 Page 1 28 Side 2 30 Flange 32 Step 34 1st extension part 36 Second extension part 38 Fixed part V1 1st space V2 2nd space O1 1st center position O2 2nd center position

Claims

1. 1. A position measurement method for measuring a position of a cylindrical measurement object disposed on a wall portion, comprising: a step of placing at least three measurement tools having target markers at different positions on a measurement surface side of the measurement object such that the target markers face the measurement surface; acquiring imaging data by photographing the measurement object together with a reference surface of the measurement object and the at least three measurement tools; specifying position coordinates of a characteristic portion of the measurement object in a first coordinate system based on a plurality of position coordinates of the target markers of each of the at least three measurement jigs specified by image analysis of the imaging data; determining a measurement result by transforming the position coordinates into a second coordinate system defined by the reference plane and a normal axis relative to the reference plane; Equipped with the measurement object is disposed so as to penetrate the wall portion, a tilt of the measurement object with respect to the wall portion, the tilt being specified by a first center position of a first end face of the measurement object that is on the measurement surface side, and a second center position of a second end face of the measurement object that is on the opposite side to the first end face with respect to the wall portion, based on the first center position and design information of the measurement object.

2. The position measuring method according to claim 1 , further comprising the step of determining whether the measurement result is within an allowable range.

3. The position measuring method according to claim 1 , wherein the at least three measuring tools include four or more measuring tools.

4. The position measuring method according to claim 1 , wherein the at least three measuring jigs are arranged on at least one of an inner periphery or an outer periphery of an end face of the measurement surface side of the measurement object.

5. The measurement object has a cylindrical shape, The position measuring method according to claim 1 , wherein the at least three measuring jigs are arranged at different positions along a periphery of the measurement surface side of the measurement object.

6. The measurement object has a rectangular cylindrical shape, The position measuring method according to claim 1 , wherein the at least three measuring jigs are disposed at at least some corners of an end face of the measurement object on the side of the measurement surface.

7. The measuring jig is a main body having a first surface on which the target marker is provided, and a second surface facing the measurement object when the main body is placed on the measurement object so that the target marker faces the measurement surface; a flange portion extending from the main body along the measurement surface and forming a step portion between the flange portion and the second surface; a fixing portion for detachably fixing the main body to the measurement object; The position measurement method according to claim 1 , further comprising:

8. The main body has a first extension portion and a second extension portion extending from a central portion where the target marker is provided along a first direction and a second direction that intersect with each other, The position measuring method according to claim 7 , wherein the flange portion is provided along an edge portion of the main body on a side where an intersection angle between the first extension portion and the second extension portion is an obtuse angle.

9. The position measuring method according to claim 7 , wherein the fixed portion is at least one magnet embedded in the main body portion.

Images