Reference image generation method

Abstract

To realize a reference image generation method that can easily generate an image for determination of the suitability of the insertion amount of an insertion port for a receiving port.SOLUTION: A reference image generation method includes model generation step (S21) to generate a 3D model of a joint part, model image generation step (S22) to generate a model image when a 3D model is photographed from a predetermined direction, and reference image generation step (S23) to generate a reference image based on the model image.SELECTED DRAWING: Figure 12

Description

[Technical Field]

[0001] The present invention relates to a method for generating a reference image for determining the joining state of a pipe joint. [Background technology]

[0002] Patent Document 1 discloses a pipe inspection device for inspecting pipe joints. The pipe inspection device includes an annular member that is arranged in a ring shape to surround the periphery of the pipe and has an open end that is partially open, and an inspection device attached to the annular member. The inspection device is, for example, an imaging device, and is capable of simultaneously capturing images of the entire outer circumference of the pipe. A sealing member with a marker member is used at the pipe joint. The marker member is made of a colored member that is different in color from the color of the rest of the sealing member. If the color of the colored member is recognized in the image captured by the imaging device, it can be determined that the joint condition is improper. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2016-50770 A Summary of the Invention [Problem to be solved by the invention]

[0004] However, the pipe inspection device in Patent Document 1 is designed to determine the condition of a sealing member at a pipe joint. In other words, this pipe inspection device cannot determine whether the insertion amount of the spigot into the socket is appropriate.

[0005] An object of one aspect of the present invention is to provide a reference image generating method capable of generating a judgment image that allows easy judgment as to whether the insertion amount of a spigot into a socket is appropriate. [Means for solving the problem]

[0006] In order to solve the above problem, one embodiment of the reference image generation method of the present invention is a reference image generation method for generating a reference image for determining the joining state of a joint portion formed by inserting a spigot formed on the end of a first pipe into a receiving port of a second pipe, wherein the first pipe has an index line on its surface that serves as an indicator for determining whether the insertion amount of the spigot of the first pipe into the receiving port of the second pipe is appropriate, and includes the following steps: a model generation step for generating a three-dimensional model of the joint portion in which the spigot of the first pipe is inserted to an appropriate degree into the receiving port of the second pipe; a model image generation step for generating a model image that is an image of the three-dimensional model when photographed from a predetermined direction; and a reference image generation step for generating a reference image that is superimposed on the image of the index line when the insertion amount of the spigot into the receiving port is appropriate, based on the position of an image of the index line in the model image. [Effects of the Invention]

[0007] According to one aspect of the present invention, by generating a reference image using a three-dimensional model of a joint portion, it is possible to easily generate a reference image for each condition such as bending angle and nominal diameter. [Brief explanation of the drawings]

[0008] [Figure 1] FIG. 10 is a diagram showing an example of an image of a pipe joint portion. [Figure 2] 1 is a block diagram showing the configuration of a main part of an insertion amount determining device according to a first embodiment. [Figure 3] 10 is a diagram showing extraction of the contour of a first pipe by a contour extraction unit. FIG. [Figure 4] 10 is a diagram showing extraction of the contour of a second pipe by a contour extraction unit. FIG. [Figure 5] FIG. 10 is a diagram showing a state in which the first tube is bent toward the front side of the paper with respect to the second tube. [Figure 6] FIG. 10 is a diagram showing a state in which the first tube is bent toward the back of the page relative to the second tube. [Figure 7] 10A and 10B are diagrams illustrating examples of determination images in which the insertion amount is determined to be appropriate. [Figure 8] FIG. 10 is a diagram showing an example of a determination image in which it is determined that the insertion amount is inappropriate. [Figure 9] FIG. 10 is a diagram showing another example of a determination image in which the insertion amount is determined to be inappropriate. [Figure 10] 3 is a flowchart showing processing in the arithmetic device according to the first embodiment. [Figure 11] FIG. 10 is a block diagram showing the configuration of the main part of an insertion amount determining device according to a second embodiment. [Figure 12] 10 is a flowchart showing a procedure for generating a reference image. [Figure 13] FIG. 10 is a diagram for explaining a three-dimensional model of a joint portion. [Figure 14] 10A and 10B are diagrams for explaining changes in bending angle in a three-dimensional model of a joint portion. DETAILED DESCRIPTION OF THE INVENTION

[0009] [Embodiment 1] Hereinafter, one embodiment of the present invention will be described in detail.

[0010] FIG. 1 is a diagram showing an example of a joint image of a pipe joint. FIG. 1 shows a joint image of a joint between a first pipe P1 and a second pipe P2. The joint is formed by inserting a spigot formed at the end of the first pipe P1 into a socket formed at the end of the second pipe P2. There are no particular restrictions on the materials of the first pipe P1 and the second pipe P2, and they may be metal or resin.

[0011] The first pipe P1 has an index line LP1 on its surface. The index line LP1 serves as an index for determining the insertion depth and bending angle of the insertion port of the first pipe P1 relative to the socket of the second pipe P2. The index line LP1 is a solid line or a dashed line. When the index line LP1 is a dashed line, it is often drawn so that the index line LP1 is visible on at least one of the radial ends of the image of the first pipe P1 regardless of the circumferential position from which the first pipe P1 is imaged, but there are exceptions. In the following description, the insertion depth of the insertion port of the first pipe P1 relative to the socket of the second pipe P2 may be simply referred to as the insertion depth.

[0012] 2 is a block diagram showing the configuration of the main parts of the insertion amount determining device 1 according to embodiment 1. As shown in FIG. 2, the insertion amount determining device 1 includes a calculation device 10, a camera 20, a storage device 30, and a display device 40.

[0013] The calculation device 10 executes a process for determining whether the insertion amount of the pipe is appropriate. The calculation device 10 includes a joint image capturing unit 11, a contour extracting unit 12, a bending angle calculating unit 13, a reference image acquiring unit 14, a determination image generating unit 15, an index line extracting unit 16, and an insertion amount determining unit 17.

[0014] The joint image capturing unit 11 captures a joint image of the joint portion where the insertion port of the first pipe P1 is inserted into the receiving port P2 of the second pipe using the camera 20. An example of the joint image is as shown in Figure 1. The contour extraction unit 12 extracts the contours of the first pipe P1 and the second pipe P2 from the image captured by the joint image capturing unit 11.

[0015] FIG. 3 is a diagram illustrating the extraction of the contour of the first pipe P1 by the contour extraction unit 12. In FIG. 3, an example of a joint image is indicated by the reference numeral 3100. In a saturation image obtained by HSV (Hue Saturation Value) conversion of the joint image, there is a large difference in saturation between the images of the first pipe P1 and the second pipe P2 and the background image of soil. The contour extraction unit 12 generates an image indicated by the reference numeral 3200 in FIG. 3 by removing areas with high saturation, i.e., the areas of the images of the first pipe P1 and the second pipe P2, from the saturation image.

[0016] Furthermore, the contour extraction unit 12 generates an image in which unnecessary background is removed, leaving only an image of the background near the first pipe P1, as indicated by reference numeral 3300 in Fig. 3. Furthermore, the contour extraction unit 12 generates an image in which only the region R1 of the first pipe P1 is extracted, as indicated by reference numeral 3400 in Fig. 3. The contour extraction unit 12 extracts the contour of the region R1 as the contour of the first pipe P1.

[0017] FIG. 4 is a diagram illustrating the extraction of the contour of the second pipe P2 by the contour extraction unit 12. Similar to the extraction of the contour of the first pipe P1, the contour extraction unit 12 generates an image, designated by reference numeral 4100 in FIG. 4, in which the image regions of the first pipe P1 and the second pipe P2 have been removed from the saturation image. Next, the contour extraction unit 12 generates an image, designated by reference numeral 4200 in FIG. 4, in which unnecessary background has been removed and only the image of the background near the second pipe P2 remains. Furthermore, the contour extraction unit 12 generates an image, designated by reference numeral 4300 in FIG. 4, in which only the region R2 of the second pipe P1 has been extracted. The contour extraction unit 12 extracts the contour of the region R2 as the contour of the second pipe P2.

[0018] The bend angle calculation unit 13 calculates the bend angle in a predetermined direction between the first pipe P1 and the second pipe P2 at the joint portion based on the contours of the first pipe P1 and the second pipe P2 extracted by the contour extraction unit 12. In this embodiment, the bend angle calculation unit 13 calculates the bend angle between the first pipe P1 and the second pipe P2 in a direction (first direction) perpendicular to the axial direction of the second pipe P2.

[0019] Fig. 5 is a diagram showing a state in which the first pipe P1 is bent toward the front side of the paper with respect to the second pipe P2. Fig. 6 is a diagram showing a state in which the first pipe P1 is bent toward the back side of the paper with respect to the second pipe P2. A method for the bending angle calculation unit 13 to calculate the bending angle between the first pipe P1 and the second pipe P2 in the first direction will be described with reference to Figs. 5 and 6. In the following description, the first direction corresponds to the direction perpendicular to the paper.

[0020] The bend angle calculation unit 13 derives the center lines of the first pipe P1 and the second pipe P2 based on the contours of the first pipe P1 and the second pipe P2 extracted by the contour extraction unit 12. Next, the bend angle calculation unit 13 calculates the angle θ0 formed by the center lines of the first pipe P1 and the second pipe P2. The bend angle calculation unit 13 also calculates the angles θ1 and θ2 (θ1≦θ2) formed between each of the two side surfaces of the first pipe P1 and the end face of the second pipe P2. The bend angle calculation unit 13 also calculates the angles θ3 and θ4 formed by the center line of the first pipe P1 and each of the contour lines of the two side surfaces of the first pipe P1. Furthermore, the bend angle calculation unit 13 calculates the above-mentioned bend angles by referring to a pre-prepared table showing the correspondence between angles θ0 to θ4 and bend angles in the first direction.

[0021] The reference image acquisition unit 14 acquires a reference image CI (see FIG. 7, etc.) prepared according to the bending angle to determine whether the insertion amount according to the bending angle calculated by the bending angle calculation unit 13 is appropriate. In this embodiment, the reference image CI is a pair of markers arranged in positions symmetrical to each other about the axis of the second pipe P2, and corresponds to the position of the image of the index line LP1 when the insertion amount is appropriate. When the insertion amount and bending angle at the joint portion are appropriate, the reference image CI is superimposed on the image of the index line LP1. In this embodiment, the reference image CI is superimposed on the outline portion of at least one side surface of the first pipe P1 in the joint image.

[0022] In this embodiment, a plurality of reference images CI are prepared according to the bending angle between the first pipe P1 and the second pipe P2 in the first direction. Specifically, the reference images CI are prepared for each 1° bending angle in the range of -4° to +4°. However, the reference images CI prepared in the insertion amount determining device 1 are not limited to this, and may be prepared for each bending angle different from 1° in a range other than -4° to +4°.

[0023] Preferably, a plurality of reference images CI are prepared according to the bending angles in the first direction and the second direction perpendicular to both the axial direction of the second pipe P2 and the first direction. More preferably, a plurality of reference images CI are prepared according to the nominal diameter of the first pipe P1.

[0024] The determination image generating unit 15 generates a determination image for determining whether the insertion amount is appropriate by superimposing the reference image CI acquired by the reference image acquiring unit 14 on the joint image. In the determination image, if the insertion amount is appropriate, the reference image CI is superimposed on the image of the index line LP1. Therefore, whether the insertion amount is appropriate can be easily determined based on whether the reference image CI is superimposed on the image of the index line LP1.

[0025] The reference image acquisition unit 14 selects and acquires a reference image CI corresponding to the bending angle in the first direction in the joint image from the multiple reference images CI prepared as described above. Therefore, the determination image generation unit 15 can generate a determination image using an appropriate reference image CI corresponding to the bending angle. In this case, the reference image CI will not be superimposed on the image of the index line LP1 not only when the insertion amount is inappropriate but also when the bending angle is outside the appropriate range, so that the appropriateness of the bending angle can also be determined. Furthermore, as described above, when reference images CI are prepared according to the bending angles in the first direction and the second direction and / or the nominal diameter of the first pipe, the determination image generation unit 15 can generate a determination image using a more appropriate reference image CI.

[0026] As described above, the reference image CI is superimposed on the outline of at least one side of the first pipe P1 in the joint image. Therefore, the determination image generating unit 15 can generate a determination image that can determine whether the insertion amount is appropriate based on whether the reference image CI is superimposed on the image of the index line LP1 in the outline of at least one side of the image of the first pipe P1.

[0027] The index line extraction unit 16 extracts an image of the index line LP1 from the determination image. The index line extraction unit 16 extracts the image of the index line LP1 by, for example, extracting a region of the color of the index line LP1 from the joint image. If the extracted image of the index line LP1 is incomplete, for example, because it is interrupted in the middle, the image may be approximated by an ellipse to reproduce a complete image of the index line LP1. The insertion amount determination unit 17 determines whether the insertion amount is appropriate. If the reference image CI is superimposed on the image of the index line LP1 extracted by the index line extraction unit 16, the insertion amount determination unit 17 determines whether the insertion amount is appropriate. That is, the insertion amount determination unit 17 determines whether the insertion amount is appropriate based on the image of the index line LP1 extracted by the index line extraction unit 16 and the reference image CI. Therefore, the insertion amount determination device 1 can automatically determine whether the insertion amount is appropriate without relying on visual inspection by an operator.

[0028] 7 is a diagram showing an example of a determination image for determining that the insertion amount is appropriate. In the example shown in FIG. 7, the reference image CI is superimposed on the image of the index line LP1 at the outline portion of the first pipe P1. Therefore, the insertion amount determination unit 17 determines that the insertion amount is appropriate.

[0029] 8 is a diagram showing an example of a determination image for which it is determined that the insertion amount is inappropriate. In the example shown in Fig. 8, the reference image CI is not superimposed on the image of the index line LP1 at the outline portion of the first pipe P1. Therefore, the insertion amount determination unit 17 determines that the insertion amount is inappropriate.

[0030] Fig. 9 is a diagram showing another example of a determination image for which it is determined that the insertion amount is inappropriate. In the example shown in Fig. 9, the index line LP1 is a dashed line instead of a solid line. Therefore, in the example shown in Fig. 9, the index line LP1 appears only on one side of the first tube P1. In the example shown in Fig. 9, the reference image CI is not superimposed on the image of the index line LP1. Therefore, the insertion amount determination unit 17 determines that the insertion amount is inappropriate.

[0031] Furthermore, in the determination image, even if the insertion amount is appropriate, if the bending angle is inappropriate, the reference image CI is not superimposed on the image of the index line LP1. Therefore, the insertion amount determination device 1 can determine that not only the insertion amount but also the bending angle is inappropriate. In other words, the insertion amount determination device 1 is a device that can be used to determine the suitability of the joining state at the joint portion, not just the suitability of the insertion amount.

[0032] If the index line LP1 does not appear on either side of the first pipe P1 in the joint image, the image of the index line LP1 may be approximated by an ellipse to recreate the complete image of the index line LP1, as described above. In this case, the insertion amount determination unit 17 determines that the insertion amount is appropriate if the reference image CI is superimposed on the recreated image of the complete index line LP1. The position of the reference image CI is not limited to being superimposed on the outline of the side of the first pipe P1, and may be superimposed on, for example, the center of the first pipe P1 in the width direction.

[0033] As described above, the camera 20 is an imaging device that allows the joint image capturing unit 11 to capture an image of the joint portion. The storage device 30 stores information necessary for processing by the calculation device 10. For example, the storage device 30 stores the plurality of reference images CI described above. The display device 40, under the control of the calculation device 10, displays an image for presenting information to the worker. For example, the insertion amount determination unit 17 causes the display device 40 to display an image showing the determination result as to whether the insertion amount is appropriate.

[0034] (Processing in the arithmetic device 10) FIG. 10 is a flowchart showing the processing in the calculation device 10. The processing in the calculation device 10 is as follows: The joint image capturing unit 11 captures a joint image (S11, joint image capturing step). The contour extraction unit 12 extracts the contours of the first pipe P1 and the second pipe P2 from the joint image (S12, contour extraction step). The bending angle calculation unit 13 calculates the bending angle based on the contours of the first pipe P1 and the second pipe P2 (S13, bending angle calculation step). The reference image acquisition unit 14 acquires a reference image CI according to the bending angle (S14, reference image acquisition step). The determination image generation unit 15 generates a determination image by superimposing the reference image CI on the joint image (S15, determination image generation step).

[0035] Furthermore, the index line extraction unit 16 extracts an image of the index line LP1 from the determination image (S16). The insertion amount determination unit 17 determines whether the reference image CI is superimposed on the image of the index line LP1 (S17). If the reference image CI is superimposed on the image of the index line LP1 (YES in S17), the insertion amount determination unit 17 determines that the insertion amount is appropriate (S18). If the reference image CI is not superimposed on the image of the index line LP1 (NO in S17), the insertion amount determination unit 17 determines that the insertion amount is inappropriate (S19).

[0036] Through the above process, the insertion amount determining device 1 generates an image for determination. Furthermore, the insertion amount determining device 1 determines whether the insertion amount is appropriate based on the image for determination. Therefore, the insertion amount determining device 1 can easily determine whether the insertion amount is appropriate. After step S19, the process may be executed again from step S11, taking into account the possibility of an erroneous determination. Also, the connection between the first pipe P1 and the second pipe P2 at the joint portion may be temporarily released and then reconnected.

[0037] [Embodiment 2] Other embodiments of the present invention will be described below. For ease of explanation, the same reference numerals will be used to designate components having the same functions as those described in the above embodiment, and the description thereof will not be repeated.

[0038] Fig. 11 is a block diagram showing the configuration of the main parts of an insertion amount determination device 1A according to embodiment 2. As shown in Fig. 11, the insertion amount determination device 1A differs from the insertion amount determination device 1 in that it includes a calculation device 10A instead of the calculation device 10. The calculation device 10A differs from the calculation device 10 in that it does not include the index line extraction unit 16 and the insertion amount determination unit 17, but includes a determination image output unit 18.

[0039] The determination image output unit 18 outputs the determination image generated by the determination image generation unit 15 to the display device 40. Therefore, in the insertion amount determination device 1A, an operator can visually determine whether the insertion amount is appropriate or not based on the determination image displayed on the display device 40.

[0040] The processing in the arithmetic device 10A is similar to the processing in the arithmetic device 10 (see FIG. 10) with respect to steps S11 to S15. After step S15, in the arithmetic device 10A, the determination image output unit 18 outputs the determination image to the display device 40. The arithmetic device 10A does not execute steps S16 to S19.

[0041] However, in the insertion amount determining device 1A, the calculation device 10A may include not only the index line extraction unit 16 and the insertion amount determining unit 17 but also the determination image output unit 18. In this case, in the insertion amount determining device 1A, the insertion amount determining unit 17 determines whether the insertion amount is appropriate, and the determination image output unit 18 outputs a determination image to the display device 40. In other words, the calculation device 10A executes steps S16 to S19 and then outputs a determination image to the display device 40. This allows the operator to check whether the determination made by the insertion amount determining unit 17 is appropriate.

[0042] Furthermore, when the calculation device 10A includes the index line extraction unit 16, the insertion amount determination unit 17, and the determination image output unit 18, the determination image output unit 18 may change the display mode of the reference image CI in the determination image depending on the result of the determination by the insertion amount determination unit 17. For example, the determination image output unit 18 changes the color of the reference image CI depending on the result of the determination by the insertion amount determination unit 17. In this case, the operator can easily recognize the result of the determination by the insertion amount determination unit 17 from the color of the reference image CI.

[0043] [Embodiment 3] A method for generating the reference image CI in the above-described embodiment will be described below.

[0044] FIG. 12 is a flowchart showing a reference image generating method. For convenience, in the following description, each step is assumed to be performed by a "reference image generating device." As shown in FIG. 12, the reference image generating device generates a three-dimensional model of a joint portion in which the insertion port of the first pipe P1 is inserted appropriately into the socket of the second pipe P2 (S21, model generating step). The reference image generating device creates the three-dimensional model using, for example, computer-aided design (CAD). The reference image generating device generates a model image, which is an image of the three-dimensional model photographed from a predetermined direction (S22, model image generating step). Based on the position of the image of the index line LP1 in the model image, the reference image generating device generates a reference image, which is an image superimposed on the image of the index line LP1 when the insertion amount of the insertion port of the first pipe P1 into the socket of the second pipe P2 is appropriate (S23, reference image generating step).

[0045] Fig. 13 is a diagram for explaining a three-dimensional model of a joint part. In Fig. 13, a top view of a model of a joint part in a state where the insertion amount is appropriate and minimum is indicated by reference numeral 1301, and a side view of the model is indicated by reference numeral 1302. Furthermore, a top view of a model of a joint part in a state where the insertion amount is appropriate and maximum is indicated by reference numeral 1303, and a side view of the model is indicated by reference numeral 1304.

[0046] In addition to the index line LP1, the first tube P1 has a second index line LP2 on its surface. The second index line LP2 is a line used to determine the appropriateness of the insertion depth based on its positional relationship with the end face P21 of the second tube P2. As shown by reference numerals 1301 and 1302 in FIG. 13, the appropriate and minimum insertion depth is achieved when the second index line LP2 contacts the end face P21 at only one point and the second tube P2 does not overlap other areas of the second index line LP2. As shown by reference numerals 1303 and 1304 in FIG. 13, the appropriate and maximum insertion depth is achieved when the second index line LP2 contacts the end face P21 at only one point and the second tube P2 overlaps other areas of the second index line LP2.

[0047] In the model generation step, the reference image generation device generates a 3D model of the joint portion in the two states described above. In the model image generation step, an image is generated when the imaging range RPIC indicated by reference numerals 1301 and 1303 is imaged from the imaging positions POS indicated by reference numerals 1302 and 1304 in FIG. 13. The imaging position POS is a position that is equal to the position of the end face P21 in the axial direction of the second pipe P2 and is separated a predetermined distance from the central axis of the second pipe P2 in the radial direction. The predetermined distance is, for example, 200 mm, but is not limited to this.

[0048] 14 is a diagram for explaining a change in the bending angle in a three-dimensional model of a joint portion. As described above, a plurality of reference images CI are prepared according to the bending angle of the joint portion. Therefore, in the model image generating step, the reference image generating device needs to generate a plurality of model images in which the bending angle of the three-dimensional model is changed in order to generate a plurality of reference images.

[0049] In this embodiment, the reference image generating device changes the bending angle of the three-dimensional model by rotating the first pipe P1 relative to the second pipe P2 around a predetermined rotation center P22. The rotation center P22 is located on the central axis of the second pipe P2. The position of the rotation center P22 in the axial direction of the second pipe P22 is equal to the position in the axial direction of a valve (not shown) disposed inside the second pipe P2. The valve is a sealing member for sealing the joint portion. At the joint portion, the first pipe P1 and the second pipe P2 abut against each other via the valve.

[0050] The reference image generating device generates a 3D model for each flexion angle, with the insertion amount being the appropriate minimum and the insertion amount being the appropriate maximum. The reference image generating device generates the reference image CI so that it overlaps with the index line LP1 in both the appropriate and minimum insertion amount and the appropriate and maximum insertion amount.

[0051] As described above, the reference image generating device generates a 3D model of the joint portion and generates a reference image CI using the 3D model. Therefore, the reference image generating device can easily generate a reference image CI for each condition, such as the bending angle of the joint portion and the nominal diameter of the first pipe P1.

[0052] [Software implementation example] The control blocks of the insertion amount determination device 1, 1A (particularly the joint image capturing unit 11, contour extraction unit 12, bending angle calculation unit 13, reference image acquisition unit 14, determination image generation unit 15, index line extraction unit 16, insertion amount determination unit 17, and determination image output unit 18) may be realized by a logic circuit (hardware) formed on an integrated circuit (IC chip) or the like, or may be realized by software.

[0053] In the latter case, the insertion amount determination device 1, 1A includes a computer that executes instructions of a program, which is software that realizes each function. This computer includes, for example, one or more processors and a computer-readable recording medium storing the program. The object of the present invention is achieved when the processor in the computer reads and executes the program from the recording medium. The processor may be, for example, a CPU (Central Processing Unit). The recording medium may be a "non-transitory tangible medium," such as a ROM (Read Only Memory), a tape, a disk, a card, a semiconductor memory, or a programmable logic circuit. The device may also include a RAM (Random Access Memory) for loading the program. The program may be supplied to the computer via any transmission medium capable of transmitting the program (such as a communication network or broadcast waves). Note that one aspect of the present invention may also be realized in the form of a data signal embedded in a carrier wave, in which the program is embodied by electronic transmission.

[0054] 〔summary〕 The present invention can also be expressed as follows.

[0055] An insertion amount determination device according to one aspect of the present invention is a device for determining the joining state of a joint portion formed by inserting a spigot formed at an end of a first pipe into a socket formed at an end of a second pipe, the device having an index line on the surface of the first pipe that serves as an index for determining whether the insertion amount of the spigot of the first pipe into the socket of the second pipe is appropriate, and the device includes a joint image capture unit that captures a joint image of the joint portion where the spigot of the first pipe is inserted into the socket of the second pipe, and a loop extractor that extracts the contours of the first pipe and the second pipe from the joint image. The apparatus comprises a contour extraction unit, a bending angle calculation unit that calculates the bending angle in a predetermined direction between the first pipe and the second pipe at the joint portion based on the contour, a reference image acquisition unit that acquires a reference image prepared according to the bending angle in order to determine whether the insertion amount of the insertion port of the first pipe into the receiving port of the second pipe is appropriate according to the bending angle, and a judgment image generation unit that generates a judgment image for determining whether the insertion amount of the insertion port of the first pipe into the receiving port of the second pipe is appropriate by superimposing the reference image on the joint image.

[0056] According to the above configuration, the determination image generation unit generates a determination image in which a reference image corresponding to the bending angle of the joint portion between the first pipe and the second pipe is superimposed on the joint image. When the insertion amount of the spigot into the socket is appropriate, the reference image is superimposed on an image of an index line on the surface of the first pipe. Therefore, the insertion amount determination device can generate a determination image that makes it easy to determine whether the insertion amount of the spigot into the socket is appropriate.

[0057] In addition, the insertion amount determination device according to one aspect of the present invention may further include an index line extraction unit that extracts an image of the index line from the determination image, and an insertion amount determination unit that determines that the insertion amount is appropriate if the reference image is superimposed on the extracted image of the index line.

[0058] According to the above configuration, the insertion amount determination unit determines whether the insertion amount of the insertion port into the receiving port is appropriate based on the image of the index line extracted by the index line extraction unit and the reference image. Therefore, the appropriateness of the insertion amount can be determined automatically without relying on visual inspection by an operator.

[0059] The insertion amount determining device according to an aspect of the present invention may further include a determination image output unit that outputs the determination image to a display device.

[0060] According to the above configuration, the worker can visually determine whether the insertion amount of the insertion port into the socket is appropriate based on the determination image output by the determination image output unit to the display device.

[0061] Furthermore, in an insertion amount determination device according to one embodiment of the present invention, it is preferable that a plurality of reference images are prepared according to the bending angle in a first direction perpendicular to the axial direction of the second pipe, and that the reference image acquisition unit selects and acquires the reference image from the plurality of reference images according to the bending angle in the first direction in the joint image.

[0062] According to the above configuration, the reference image acquisition unit selects and acquires an appropriate reference image according to the bending angle of the joint portion in the first direction. Therefore, the determination image generation unit can generate the determination image using the appropriate reference image acquired by the reference image acquisition unit. Furthermore, even if the bending angle is outside the appropriate range, the reference image will not be superimposed on the index line, making it possible to determine whether the bending angle is appropriate.

[0063] In addition, in an insertion amount determination device according to one embodiment of the present invention, it is preferable that a plurality of reference images are prepared according to the bending angle in each of the first direction and a second direction perpendicular to both the axial direction of the second tube and the first direction.

[0064] According to the above configuration, the reference image acquisition unit selects and acquires a more appropriate reference image according to the bending angle of the joint portion in both the first direction and the second direction, and therefore the determination image generation unit can generate a determination image using the more appropriate reference image acquired by the reference image acquisition unit.

[0065] In addition, in an insertion amount determination device according to one embodiment of the present invention, it is preferable that a plurality of reference images are prepared according to the nominal diameter of the first pipe, and the reference image acquisition unit selects and acquires the reference image according to the nominal diameter of the first pipe in the joint image from the plurality of reference images.

[0066] According to the above configuration, the reference image acquisition unit selects and acquires an appropriate reference image according to the nominal diameter of the first pipe, i.e., the width of the first pipe in the joint image. Therefore, the determination image generation unit can generate a determination image using the appropriate reference image acquired by the reference image acquisition unit.

[0067] In the insertion amount determining device according to one aspect of the present invention, it is preferable that the reference image is an image that is superimposed on a contour portion of at least one side surface of the first pipe in the joint image.

[0068] According to the above configuration, the judgment image generation unit can generate a judgment image that can determine whether the insertion amount is appropriate based on whether the reference image is superimposed on the image of the index line in the contour portion of at least one side of the image of the first tube.

[0069] According to another aspect of the present invention, there is provided a method for determining a joining state of a joint formed by inserting a spigot formed on an end of a first pipe into a socket of a second pipe, the first pipe having an index line on its surface that serves as an index for determining whether the insertion amount of the spigot of the first pipe into the socket of the second pipe is appropriate, the method comprising the steps of: capturing a joint image of the joint where the spigot of the first pipe is inserted into the socket of the second pipe; and extracting contours of the first pipe and the second pipe from the joint image. a bending angle calculation step of calculating the bending angle in a predetermined direction between the first pipe and the second pipe at the joint portion based on the contour; a reference image acquisition step of acquiring a reference image prepared according to the bending angle in order to determine whether the insertion amount of the insertion port of the first pipe into the receiving port of the second pipe is appropriate according to the bending angle; and a judgment image generation step of generating a judgment image for determining whether the insertion amount of the insertion port of the first pipe into the receiving port of the second pipe is appropriate by superimposing the reference image on the joint image.

[0070] According to the above configuration, the same effects as those of the above-mentioned insertion amount determining device can be achieved.

[0071] The insertion amount determining device according to each aspect of the present invention may be realized by a computer. In this case, the control program for the insertion amount determining device, which causes the computer to operate as each part (software element) of the insertion amount determining device, and the computer-readable recording medium on which the control program is recorded, also fall within the scope of the present invention.

[0072] According to one aspect of the present invention, an insertion amount determining device can be realized that can generate a determination image that allows easy determination of whether the insertion amount of a insertion port into a receiving port is appropriate.

[0073] The present invention is not limited to the above-described embodiments, and various modifications are possible within the scope of the claims. Embodiments obtained by appropriately combining the technical means disclosed in different embodiments are also included in the technical scope of the present invention. [Explanation of symbols]

[0074] 1, 1A Insertion amount determination device 11 Joint image capturing unit 12 Contour extraction section 13 Bend angle calculation section 14 Reference image acquisition unit 15 Judgment image generation unit 16 Index line extraction part 17 Insertion amount determination unit 18. Image output unit for judgment

Claims

[Claim 1] A reference image generating method for generating a reference image, which is an image for determining a joining state of a joint portion formed by inserting a spigot formed at an end of a first pipe into a receiving port of a second pipe, the reference image being an image superimposed on a joint image captured by an imaging means of the joint portion, the first pipe has an index line on its surface serving as an index for determining whether the insertion amount of the insertion port of the first pipe into the receiving port of the second pipe is appropriate; a model generation step of generating a three-dimensional model of a joint portion in which the spigot of the first pipe is inserted into the socket of the second pipe to an appropriate degree; a model image generating step of generating a model image which is an image obtained when the three-dimensional model is photographed from a predetermined direction; a reference image generating step of generating a reference image based on the position of the image of the index line in the model image, so that the image of the index line is superimposed on the image of the index line in a joint image of the joint portion when the insertion amount of the insertion port into the socket is appropriate, and so that the image of the index line is not superimposed on the image of the index line in the joint image when the insertion amount of the insertion port into the socket is not appropriate.

Images