Inspection system and inspection method

Abstract

To efficiently inspect a pipe.SOLUTION: An inspection system includes an ultrasonic sensor, an imaging device, an optical member, and a motor for rotating the optical member in a circumferential direction of a pipe so that the ultrasonic sensor transmits ultrasonic waves to each part in the circumferential direction of the pipe through the optical member and receives its reflection waves, and the imaging device images each of the parts in the circumferential direction of the inner surface of the pipe through the optical member, and includes a sensor head moved in a longitudinal direction of the pipe, a pipe thickness calculation part for determining thicknesses of each of the parts in the circumferential direction and the longitudinal direction of the pipe from the result of the transmission and reception by the ultrasonic sensor, and an image integration part for generating image information obtained by combining an image indicating the thicknesses of each of the parts in the circumferential direction and the longitudinal direction of the pipe determined by the pipe thickness calculation part, with an image indicating each of the parts in the circumferential direction and the longitudinal direction of the inner surface of the pipe obtained from the result of imaging by the imaging device.SELECTED DRAWING: Figure 1A

Description

[Technical Field]

[0001] FIELD OF THE INVENTION Embodiments of the present invention relate to an inspection system and an inspection method. [Background technology]

[0002] Pipes such as water pipes are underground. Therefore, when inspecting pipes, a camera is inserted into the pipe from a fire hydrant or similar device, and the presence or absence of rust or deposits on the pipe is investigated through images captured by the camera or other imaging device. In addition, an ultrasonic sensor can be inserted into the pipe and the thickness of the pipe wall can be measured by detecting the reflected waves of ultrasonic waves transmitted from the ultrasonic sensor toward the pipe wall. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent No. 6039599 Summary of the Invention [Problem to be solved by the invention]

[0004] Taking images of the inside of a pipe using an imaging device and measuring the pipe thickness using an ultrasonic sensor are separate tasks. Therefore, performing both tasks increases the overall workload and takes a lot of time. Furthermore, simply generating the results of imaging the inside of a pipe and the results of measuring the pipe thickness separately does not fully utilize the results of both.

[0005] An object of the present invention is to provide an inspection system and an inspection method that enable efficient inspection of pipes. [Means for solving the problem]

[0006] The inspection system of one embodiment includes a plurality of ultrasonic sensors that transmit ultrasonic waves to each part of the circumferential direction of the pipe and receive the reflected waves, an imaging device, and an optical system component that enables the imaging device to image each part of the circumferential direction of the inner surface of the pipe, and the system is also equipped with a sensor head that moves in the longitudinal direction of the pipe, a pipe thickness calculation unit that calculates the thickness of each part of the circumferential direction and longitudinal direction of the pipe from the results of transmission and reception by the plurality of ultrasonic sensors, and an image integration unit that generates image information that combines a first image representing the thickness of each part of the circumferential direction and longitudinal direction of the pipe calculated by the pipe thickness calculation unit and a second image representing each part of the circumferential direction and longitudinal direction of the inner surface of the pipe obtained from the results of imaging by the imaging device so that they can be compared, and each of the plurality of ultrasonic sensors is configured as a further plurality of ultrasonic sensors, each of which transmits ultrasonic waves in a different direction and receives the reflected waves from the transmitted ultrasonic waves. [Brief explanation of the drawings]

[0007] [Figure 1A]FIG. 1 is a diagram showing an example of the configuration of an inspection system according to a first embodiment. [Figure 1B] 1B is a diagram showing an example of the structure of the sensor head 2 shown in FIG. 1A as viewed from the longitudinal direction of the pipe 1. FIG. [Figure 2] FIG. 2 is a diagram showing an example of the configuration of a ground device 5 according to the first embodiment. [Figure 3] 1 is a diagram showing the characteristics of various reflected waves received after ultrasound is transmitted toward a pipe wall; [Figure 4] FIG. 2 is a diagram showing an example of combining development views of two types of images according to the first embodiment. [Figure 5] 5 is a flowchart showing one example (part 1) of the operation of the inspection system according to the first embodiment. [Figure 6] 6 is a flowchart showing an example (part 2) of the operation of the inspection system according to the first embodiment. [Figure 7A] 7 is a diagram showing an example of a determination criterion (guideline) used for determining the degree of deterioration performed in step S19 in each of FIGS. 5 and 6. FIG. [Figure 7B] 7 is a diagram showing an example of a determination criterion (guideline) used for determining the degree of deterioration performed in step S19 in each of FIGS. 5 and 6. FIG. [Figure 8] 5 is a diagram showing an example in which information indicating the degree of deterioration or information calling attention is added to each of the first image and the second image shown in FIG. 4. FIG. [Figure 9] FIG. 10 is a diagram showing an example of the configuration of an inspection system according to a second embodiment, focusing on a sensor head 2. [Figure 10] FIG. 10 is a diagram showing an example of the configuration of a ground device 5 according to a second embodiment. [Figure 11] FIG. 10 is a diagram showing an example of combining development views of two types of images according to the second embodiment. [Figure 12A] FIG. 10 is a diagram showing an example of the configuration of an inspection system according to a third embodiment, focusing on a sensor head 2. [Figure 12B] 12B is a diagram showing an example of the structure of the sensor head 2 shown in FIG. 12A as viewed from the longitudinal direction of the pipe 1. FIG. [Figure 13] FIG. 10 is a diagram showing an example of the configuration of a ground device 5 according to a third embodiment. [Figure 14] 10 is a flowchart showing an example of the operation of the inspection system according to the third embodiment. [Figure 15A] FIG. 10 is a diagram showing an example of the configuration of an inspection system according to a fourth embodiment, focusing on a sensor head 2. [Figure 15B] 15B is a diagram showing an example of the structure of the sensor head 2 shown in FIG. 15A as viewed from the longitudinal direction of the pipe 1. FIG. [Figure 16] 10A and 10B are diagrams showing modified examples of the arrangement of a plurality of ultrasonic sensors applied to the third and fourth embodiments. DETAILED DESCRIPTION OF THE INVENTION

[0008] Hereinafter, embodiments will be described with reference to the drawings.

[0009] First Embodiment First, the first embodiment will be described.

[0010] (composition) Fig. 1A shows an example of the configuration of an inspection system according to the first embodiment, and Fig. 1B shows an example of the structure of a sensor head 2 shown in Fig. 1A when viewed from the longitudinal direction of a pipe 1.

[0011] In this embodiment, in the inspection of a pipe 1 such as a water pipe, the pipe thickness of the pipe 1 is measured and an image of the inner surface of the pipe 1 is taken.

[0012] 1A includes a cylindrical sensor head 2 and a device (ground device) 5 placed on the ground. The ground device 5 includes an information processing device (described later) having a processor. The sensor head 2 and the ground device 5 are connected by a cable C.

[0013] The sensor head 2 is used by being inserted into the pipe 1 filled with water, for example, from the outlet of a fire hydrant H, with the cable C connected to it. The sensor head 2 can move in the longitudinal direction of the pipe 1.

[0014] The sensor head 2 is fitted with skids or tires 21. The skids or tires 21 enable the sensor head 2 to move in the longitudinal direction of the pipe 1 while maintaining a stable posture. The sensor head 2 may travel, for example, in the direction of the water flow F or in the opposite direction. The direction in which the sensor head 2 travels can be controlled by pulling, releasing, or letting out the cable C.

[0015] The sensor head 2 includes a rotatable cylindrical member 100, an ultrasonic sensor 101 that transmits and receives ultrasonic waves, a camera (imaging device) 102 that captures images, a motor 103 that generates driving force, a mirror (optical system member) 104 that reflects ultrasonic waves and light, and an acceleration sensor 105 that measures the direction of gravity (up and down). The camera 102 is equipped with lighting. Data indicating the direction of gravity measured by the acceleration sensor 105 is transmitted to a processor of an information processing device in the ground equipment 5 via a cable C.

[0016] The cylindrical member 100 is supported by a bearing. A mirror 104 is attached to the cylindrical member 100.

[0017] The ultrasonic sensor 101 and the camera 102 are arranged side by side. S represents the path of the ultrasonic wave transmitted and received by the ultrasonic sensor 101. Also, P in FIG. C represents the field of view of the camera 102.

[0018] The ultrasonic wave transmitted from the transmitting unit of the ultrasonic sensor 101 travels along a path P S The ultrasonic wave travels along the same path in the opposite direction, is reflected by mirror 104, and enters the receiving section of ultrasonic sensor 101. The signal received by ultrasonic sensor 101 is transmitted via cable C to the processor of the information processing device in ground equipment 5.

[0019] The camera 102 has a field of view P CThe camera 102 captures an image of the area on the wall of the pipe 1 that is reflected by the mirror 104. The image captured by the camera 102 is transmitted to a processor of an information processing device in the ground device 5 via a cable C.

[0020] The motor 103 rotates the cylindrical member 100 (that is, rotates the mirror 104) by driving a gear G that meshes with a part of the bearing.

[0021] Motor 103 rotates mirror 104 in the circumferential direction of pipe 1 so that ultrasonic sensor 101 transmits ultrasonic waves to various parts of pipe 1 in the circumferential direction and receives the reflected waves, and camera 102 captures images of various parts of the inner surface of pipe 1 in the circumferential direction via mirror 104. Data indicating the angle (hereinafter referred to as the "rotation angle") by which mirror 104 rotates from a reference position as a result of driving motor 103 can be obtained from motor 103. Data indicating the rotation angle can be obtained using an origin switch or rotary encoder. From this rotation angle and the above-mentioned direction of gravity, the direction in which ultrasonic waves are incident on the wall surface relative to the direction of gravity (the direction of mirror 104 relative to the direction of gravity) can be determined. Data indicating the rotation angle is transmitted to ground device 5 via cable C.

[0022] In addition to ground equipment 5, a reel 4 for winding cable C and a position measuring device 3 are also provided on the ground. Position measuring device 3 measures the length of penetration of sensor head 2 from a reference position into the pipe in the longitudinal direction (hereinafter referred to as the "penetration length") based on the number of rotations of roller 10 that contacts cable C. By measuring the penetration length, the longitudinal position of sensor head 2 within the pipe can be identified, and further, the longitudinal position within the pipe where ultrasonic waves transmitted from ultrasonic sensor 101 are incident on the wall surface can be identified. The penetration length data measured by position measuring device 3 is transmitted to a processor of an information processing device via cable C or another cable not shown.

[0023] The penetration length may be obtained by another method. For example, the position measuring device 3 may have a function to obtain the penetration length by measuring the number of rotations of the reel 4, or may have a function to obtain the penetration length by measuring the number of rotations of the tire 21.

[0024] The measurement of the pipe thickness at each part of the pipe 1 can be performed continuously while moving the sensor head 2 in the longitudinal direction of the pipe 1 and rotating the mirror 104 in the circumferential direction of the pipe 1, or the pipe thickness can be measured only when the pipe is stopped, and each time the sensor head 2 is moved a certain distance in the longitudinal direction of the pipe 1 or the mirror 104 is rotated a certain angle in the circumferential direction of the pipe 1, and the pipe thickness can be measured again when the pipe is stopped, repeating this process.

[0025] (Configuration of ground device 5) Fig. 2 shows an example of the configuration of the ground device 5 according to the first embodiment. Note that Fig. 2 also shows some of the elements on the sensor head 2 side. In addition to the position measuring device 3 described above, the ground device 5 includes a transmitter / receiver circuit 111, a motor drive circuit 113, a display unit 6, a processor 7, a memory 8, and a recording unit 9. The display unit 6, the processor 7, the memory 8, and the recording unit 9 constitute an information processing device (computer).

[0026] 2 shows only one example, and the present invention is not limited to this example. Some of the elements constituting the ground device 5 may be provided in the sensor head 2. For example, all or some of the transmitting / receiving circuit 111, the motor driving circuit 113, the processor 7, the memory 8, and the recording unit 9 may be provided in the sensor head 2.

[0027] The transmission / reception circuit 111 includes a transmission circuit that applies a transmission frequency and voltage to the ultrasonic sensor 1, a reception circuit that amplifies the signal of the reflected wave received by the ultrasonic sensor 1, and a switching circuit that switches between transmission and reception.

[0028] The motor drive circuit 113 drives the motor 103 and obtains data on the rotation angle at which the mirror 104 rotates from the reference position as a result of the driving of the motor 103 via an origin switch or the like.

[0029] The processor 7 has various functions such as a rotation control unit 71, a pipe thickness calculation unit 72, an image integration unit 73, and a deterioration determination unit 74. The various functions of the processor 7 are implemented, for example, as a program to be implemented by a computer. When executing the program, the processor 7 uses, for example, the memory 8 as a work area.

[0030] The rotation control unit 71 controls the motor drive circuit 113 to rotate the cylindrical member 100 by the motor 103 (that is, to rotate the mirror 104).

[0031] The speed at which the mirror 104 is rotated may be adjusted depending on the diameter of the pipe 2 to be measured. For example, if the diameter of the pipe 2 is large, the speed at which the mirror 104 is rotated can be reduced to prevent a decrease in the quality of the image obtained by measuring the pipe thickness and capturing an image of the pipe inner surface.

[0032] In addition, the rotation control unit 71 obtains the direction in which the ultrasonic waves are incident on the wall surface relative to the direction of gravity (i.e., the direction of the mirror 104 relative to the direction of gravity) from the rotation angle data obtained from the motor drive circuit 113 and the gravity direction data obtained from the acceleration sensor 105.

[0033] The pipe thickness calculation unit 72 calculates the thickness of each part of the pipe 1 in the circumferential and longitudinal directions from the results of transmission and reception by the ultrasonic sensor 101 .

[0034] Specifically, the pipe thickness calculation unit 72 controls the transmission / reception circuit 111 to acquire signals of reflected waves (including waves reflected by the inner surface of the pipe 1 and waves reflected by the outer surface of the pipe 1) received by the ultrasonic sensor 101, and calculates and determines the thickness of the pipe 1 from the signals. Figure 3 shows the characteristics of various reflected waves received after ultrasonic waves are transmitted toward the pipe wall.

[0035] In the graph of Fig. 3, the horizontal axis represents the time after ultrasonic waves are transmitted, and the vertical axis represents the signal level of the received reflected waves. Reflected waves W1, W2, and W3 in the graph of Fig. 3 are reflected waves that arrive at ultrasonic sensor 101 at different times after ultrasonic waves are transmitted from ultrasonic sensor 101 toward the pipe wall. Reflected wave W1 is a reflected wave reflected from the inner surface of pipe 1, reflected wave W2 is a reflected wave reflected from the outer surface of pipe 1, and reflected wave W3 is a reflected wave that is multiplexedly reflected from the outer surface of pipe 1 (such as a reflected wave that is reflected from the outer surface of pipe 1, then reflected from the inner surface of pipe 1, and then reflected again from the outer surface of pipe 1).

[0036] Here, if the signal levels of the reflected waves W1 and W2 received by the ultrasonic sensor 101 are each above a certain level, the reflected waves W1 and W2 can be detected, and the thickness of the pipe 1 can be measured from the time difference Δt between the arrival time of the reflected wave W1 and the arrival time of the reflected wave W2.

[0037] The signals of the reflected waves received by the ultrasonic sensor 101 with a time difference are transmitted from the ultrasonic sensor 101 to the pipe thickness calculation unit 72 via the transmitting / receiving circuit 111 .

[0038] The image integrator 73 generates image information that allows comparison between a development (first image) of an image showing the thickness of each part of the circumferential and longitudinal direction of the pipe 1 calculated by the pipe thickness calculator 72 and a development (second image) of an image showing each part of the circumferential and longitudinal direction of the inner surface of the pipe 1 obtained from the imaging results of the camera 102. In this case, the image integrator 73 generates the image information by adding information that allows confirmation of the circumferential position of the pipe 1 and the longitudinal position of the pipe 1 to the image information. The image integrator 73 recognizes the circumferential position of the pipe 1 from data from the acceleration sensor 105 obtained by the rotation controller 71, i.e., data indicating the direction of the mirror 104 with respect to the direction of gravity measured by the acceleration sensor 105. The longitudinal position of the pipe 1 is recognized from data indicating the penetration length measured by the position measuring device 3.

[0039] The deterioration determining unit 74 determines the degree of deterioration based on the first image and the second image obtained from the image integrating unit 73, according to the thickness of the pipe and the rust and dirt on the inner surface of the pipe.

[0040] Figure 4 shows an example of a combination of an expanded image (first image) showing the thickness of each part of the circumferential and longitudinal direction of the pipe 1 obtained from the results of transmitting and receiving ultrasonic waves by the ultrasonic sensor 101, and an expanded image (second image) showing each part of the circumferential and longitudinal direction of the inner surface of the pipe 1 obtained from the results of imaging by the camera 102.

[0041] The first and second images are each a development in which the horizontal axis represents the longitudinal position of the pipe 1 and the vertical axis represents the circumferential position of the pipe 1. In each of the developments in the first and second images, the circumferential position of the pipe 1 corresponds to the data from the acceleration sensor 105 obtained by the rotation control unit 71, i.e., the direction of the mirror 104 relative to the direction of gravity measured by the acceleration sensor 105. The longitudinal position of the pipe 1 corresponds to the penetration length measured by the position measuring device 3.

[0042] In the example of Figure 4, the first image shows a thin portion A1 of the tube 1. The second image shows a rusted portion A2 on the inner surface of the tube 1.

[0043] The image integration unit 73 generates image information by combining images of two types of unfolded views as shown in Figure 4 in a manner that aligns the longitudinal position of the tube 1, and displays the image information on the display unit 6 and stores it in the recording unit 9.

[0044] (operation) Next, an example (part 1) of the operation of the inspection system according to the first embodiment will be described with reference to the flowchart of FIG.

[0045] Initially, the sensor head 2 and the mirror 104 are each in a reference position.

[0046] First, the ultrasonic sensor 101 transmits and receives ultrasonic waves via the mirror 104 (step S11).

[0047] Next, the pipe thickness calculation unit 72 calculates the thickness of the pipe 1 from the reflected wave received by the ultrasonic sensor 101 (step S12).

[0048] Next, the camera 102 captures an image of the inner surface of the pipe 1 (step S13).

[0049] Next, the image integration unit 73 compiles the image representing the thickness of the pipe 1 calculated by the pipe thickness calculation unit 72, the image representing the inner surface of the pipe 1 captured by the camera 102, the circumferential position data of the pipe 1 obtained from data indicating the direction of the mirror 104 relative to the direction of gravity, and the longitudinal position data of the pipe 1 obtained from data indicating the penetration length measured by the position measuring device 3 as a measurement result corresponding to one point out of all the measurement results (expanded view) and stores it in a memory area (step S14).

[0050] Next, under the control of the rotation control unit 71, the mirror 104 is rotated by a predetermined angle by the motor 103 (step S15).

[0051] Here, it is determined whether the mirror 104 has made one rotation from the reference position (step S16).

[0052] If one rotation has not been completed, the process is repeated from step S11.

[0053] On the other hand, if one rotation has been made, the sensor head 2 is advanced by a predetermined length in a predetermined direction by pulling, releasing, or feeding out the cable C (step S17).

[0054] Here, it is determined whether the position of the sensor head 2 has reached the inspection end position (step S18).

[0055] If the inspection end position has not been reached, the process is repeated from step S11.

[0056] On the other hand, when the inspection end position is reached, image information is generated from the individual measurement results stored in a predetermined area so that a development (first image) of an image showing the thickness of each part in the circumferential and longitudinal directions of the pipe 1 can be compared with a development (second image) of an image showing each part in the circumferential and longitudinal directions of the inner surface of the pipe 1. Furthermore, the degree of deterioration is determined for each of the first and second images based on a predetermined determination standard (guideline) (step S19). The degree of deterioration is determined, for example, for each part (for example, for each individual area into which the inner surface of the pipe 1 is divided in advance), and also a comprehensive determination is made for the entire pipe.

[0057] (operation) Next, a second example of the operation of the inspection system according to the first embodiment will be described with reference to the flowchart of FIG.

[0058] Initially, the sensor head 2 and the mirror 104 are each in a reference position.

[0059] By pulling, releasing or sending out the cable C, the sensor head 2 is controlled to move forward little by little (step S21), and under the control of the rotation control unit 71, the motor 103 is controlled to rotate the mirror 104 little by little at a constant rotation speed (step S22). As a result, the ultrasonic waves irradiated onto the inner surface of the pipe 1 move in a spiral pattern.

[0060] After this, the same processes as steps S11 to S14 shown in the flowchart of FIG. 5 are carried out.

[0061] Furthermore, thereafter, the same processes as steps S18 and S19 shown in the flowchart of FIG. 5 are performed.

[0062] 7A and 7B show examples of criteria (guidelines) used to determine the degree of deterioration performed in step S19 in each of FIGS.

[0063] Figure 7A shows an example of the Japan Water Works Association's waterworks maintenance and management guidelines, in which the deterioration levels are determined in order of increasing severity as I, II, III, IV, and V. The deterioration level is determined by the nominal diameter of the pipe and the thickness of the pipe after deterioration. Figure 7B shows the relationship between the pipe thickness T (mm) after deterioration and the deterioration levels I, II, III, IV, and V for a nominal diameter of 75 mm (pipe thickness 7.5 mm). The smaller the pipe thickness T, the higher the deterioration level.

[0064] For example, if a pipe with a nominal diameter of 75 mm (pipe thickness 7.5 mm) deteriorates due to corrosion or other reasons, and the pipe thickness T becomes 1.0 mm or more but less than 1.2 mm, it is judged as "Deterioration Level II (urgent replacement required)." Also, if the image shows significant rust and dirt on the inside, it is judged as "cleaning required."

[0065] FIG. 8 shows an example in which information indicating the degree of deterioration or information calling attention is added to each of the first image and the second image shown in FIG.

[0066] In the example of Figure 8, in the first image, a message saying "Deterioration level II (urgent replacement required)" is displayed for a thin portion A1 of the pipe 1. In addition, in the second image, a message saying "Cleaning required" is displayed for a portion A2 of the inner surface of the pipe 1 where there is rust.

[0067] According to the first embodiment, in image information obtained by integrating a development (first image) of an image showing the thickness of each part in the circumferential and longitudinal directions of the pipe 1 obtained as a result of transmitting and receiving ultrasonic waves by the ultrasonic sensor 101 and a development (second image) of an image showing each part in the circumferential and longitudinal directions of the inner surface of the pipe 1 obtained as a result of imaging by the camera 102 using the mirror 104, the image information can be displayed on the display unit 6 or the like with information indicating the degree of deterioration or information calling attention added to each of the first image and the second image. This allows efficient pipe inspection by utilizing both the imaging of the inside of the pipe using the camera 102 and the measurement of the pipe thickness using the ultrasonic sensor 101.

[0068] <Second embodiment> Next, a second embodiment will be described, focusing on the differences from the first embodiment.

[0069] (composition) Fig. 9 shows an example of the configuration of the inspection system according to the second embodiment, focusing on the sensor head 2. Here, Fig. 1A will also be referenced as appropriate. The overall configuration of the inspection system according to the second embodiment is the same as that shown in Fig. 1A, except for the configuration of the sensor head 2.

[0070] The second embodiment differs from the first embodiment in that the sensor head 2 is provided with a laser range finder 106 instead of the camera 102 .

[0071] That is, in the first embodiment, an example in which a camera is used as an example of an imaging device is shown, but in the second embodiment, an example in which a laser rangefinder 106 is used as an imaging device other than a camera is shown. Here, the laser rangefinder 106 is also considered to be one of the imaging devices. The laser rangefinder 106 measures the uneven shape of the inner surface of the pipe 1.

[0072] The laser range finder 106 is arranged next to the ultrasonic sensor 101. L represents the path of the laser projected by the laser range finder 106.

[0073] The laser emitted from the light-emitting unit of the laser rangefinder 106 follows a path P L The laser beam passes through the cable C, is reflected by mirror 104, and enters the wall of pipe 1 perpendicularly. The laser beam reflected by the wall of pipe 1 travels the same path in the opposite direction, is reflected by mirror 104, and enters the light receiving section of laser range finder 106. The signal obtained by laser range finder 106 is transmitted to processor 7 of the information processing device in ground equipment 5 via cable C.

[0074] (Configuration of ground device 5) FIG. 10 shows an example of the configuration of the ground device 5 according to the second embodiment.

[0075] As shown in FIG. 10, the signal obtained by the laser range finder 106 is sent to the image integration unit 75 of the processor 7 .

[0076] The image integration unit 75 generates combined image information that allows a comparison between an expanded view (first image) of an image representing the thickness of each part of the pipe 1 in the circumferential and longitudinal directions calculated by the pipe thickness calculation unit 72 and an expanded view (second image) of an image representing the uneven shape of each part of the inner surface of the pipe 1 in the circumferential and longitudinal directions obtained from the results of imaging by the laser rangefinder 106.

[0077] Figure 11 shows an example of a combination of an expanded image (first image) showing the thickness of each part of the pipe 1 in the circumferential and longitudinal directions obtained from the results of transmitting and receiving ultrasonic waves by the ultrasonic sensor 101, and an expanded image (second image) showing the uneven shape of each part of the inner surface of the pipe 1 in the circumferential and longitudinal directions obtained from the results of imaging by the laser rangefinder 106.

[0078] The first image and the second image are each a development view in which the horizontal axis represents the position in the longitudinal direction of the pipe 1 and the vertical axis represents the position in the circumferential direction of the pipe 1.

[0079] In the example of Figure 11, the first image shows a thin portion B1 of the pipe 1. The second image shows a portion B2 of the pipe 1 with large irregularities on its inner surface. The size of the irregularities can be determined from the second image. For example, it is possible to diagnose that portions of the pipe 1 with irregularities of 1 mm or more are areas with a lot of rust, or that portions of the lower inner surface of the pipe 1 where irregularities are measured are areas with deposits.

[0080] The image integration unit 75 generates image information by combining images of two types of unfolded views such as those shown in Figure 11 in a way that aligns the longitudinal position of the tube 1, and displays the image information on the display unit 6 and stores it in the recording unit 9.

[0081] (operation) The operation of the inspection system according to the second embodiment is similar to that shown in FIGS. 5 and 6, and therefore a description thereof will be omitted.

[0082] According to the second embodiment, in image information obtained by integrating a development (first image) of an image showing the thickness of each part in the circumferential and longitudinal directions of the pipe 1 obtained from the results of transmitting and receiving ultrasonic waves by the ultrasonic sensor 101 and a development (second image) of an image showing each part in the circumferential and longitudinal directions of the inner surface of the pipe 1 obtained from the results of imaging by the laser rangefinder 106 using the mirror 104, the image information can be displayed on the display unit 6 or the like with information showing the degree of deterioration or information calling attention added to each of the first image and the second image. This allows efficient pipe inspection by utilizing both the imaging of the inside of the pipe using the laser rangefinder 106 and the measurement of the pipe thickness using the ultrasonic sensor 101.

[0083] <Third embodiment> Next, a third embodiment will be described, focusing on the differences from the first embodiment.

[0084] (composition) FIG. 12A shows an example of the configuration of an inspection system according to the third embodiment, focusing on the sensor head 2. FIG. 12B shows an example of the structure of the sensor head 2 shown in FIG. 12A as viewed from the longitudinal direction of the pipe 1. Here, FIG. 1A will also be referenced as appropriate. The overall configuration of the inspection system according to the third embodiment is the same as that shown in FIG. 1A, except for the configuration of the sensor head 2.

[0085] In the third embodiment, unlike the first embodiment, the sensor head 2 does not include the cylindrical member 100, the motor 103, the mirror 104, and the like.

[0086] In the third embodiment, the sensor head 2 is provided with a wide-angle lens (optical system member) 107. The wide-angle lens 107 is disposed, for example, near the front of the sensor head 2. The camera 102 is disposed near the wide-angle lens 107. C represents the field of view of the camera 102.

[0087] The camera 102 has a field of view P CThe camera 102 captures an image of the wall area of ​​the pipe 1 visible through a wide-angle lens 107. The wide-angle lens 107 makes it possible to capture an image of the inner surface of the entire circumference of the pipe 1. The image captured by the camera 102 is transmitted to the processor 7 of the information processing device in the ground device 5 via a cable C.

[0088] The ultrasonic sensor 101 is not one but a plurality of ultrasonic sensors 101. That is, a plurality of ultrasonic sensors 101-1, 101-2, 101-3, 101-4, 101-5, and 101-6 are provided on the outer periphery of the sensor head 2, and are arranged at regular intervals in the circumferential direction. S represents the path of the ultrasonic waves transmitted and received by each ultrasonic sensor. The ultrasonic waves transmitted from the transmitting unit of each ultrasonic sensor are incident perpendicularly on the wall surface of the pipe 1. The signals received by the ultrasonic sensors are transmitted via cable C to the processor of the information processing device in the ground equipment 5.

[0089] (Configuration of ground device 5) FIG. 13 shows an example of the configuration of the ground device 5 according to the third embodiment.

[0090] As shown in FIG. 13, the signal obtained by the camera 102 is sent to the image integration unit 73 of the processor 7, as in the first embodiment.

[0091] In the third embodiment, unlike the first embodiment (FIG. 2 etc.), there is no need to provide a motor 103 on the sensor head 2 side, and therefore no need to provide a motor drive circuit 113. Accordingly, the processor 7 does not include a rotation control unit 71.

[0092] The image integration unit 73 can use data indicating the direction of gravity measured by the acceleration sensor 105 to recognize, for example, the ultrasonic sensor corresponding to the up and down direction of the pipe 1, and can also recognize the up and down direction of the image captured by the camera 102.

[0093] The image integration unit 73 generates combined image information that allows a comparison between an expanded view (first image) of an image representing the thickness of each part of the circumferential and longitudinal direction of the pipe 1 calculated by the pipe thickness calculation unit 72 and an expanded view (second image) of an image representing each part of the circumferential and longitudinal direction of the inner surface of the pipe 1 obtained from the results of imaging by the camera 102.

[0094] Note that the area of ​​the pipe 1 where each ultrasonic sensor transmits and receives ultrasonic waves to measure the pipe thickness and the area of ​​the pipe 1 imaged by the camera 102 are separated by a certain distance, and information on different areas is obtained at the same time (information on the same area is obtained at different times). However, the longitudinal position of the pipe 1 can be aligned between the first image and the second image based on the information from the position measuring instrument 3 and the angle of view of the wide-angle lens 107.

[0095] (operation) Next, an example of the operation of the inspection system according to the third embodiment will be described with reference to the flowchart of FIG.

[0096] Initially, the sensor heads 2 are each in a reference position.

[0097] By pulling, releasing or feeding the cable C, the sensor head 2 is controlled to move forward little by little (step S21).

[0098] Next, the ultrasonic sensors 101-1, 101-2, 101-3, 101-4, 101-5, and 101-6 transmit and receive ultrasonic waves (step S31).

[0099] Next, the pipe thickness calculation unit 72 calculates the thickness of the entire circumference of the pipe 1 from the reflected waves received by each ultrasonic sensor 101 (step S32).

[0100] Next, the camera 102 captures an image of the inner surface of the pipe 1 (step S33).

[0101] Next, the image integration unit 73 compiles the image representing the thickness of the entire circumference of the pipe 1 calculated by the pipe thickness calculation unit 72, the image representing the inner surface of the entire circumference of the pipe 1 captured by the camera 102, the data on the circumferential position of the pipe 1, and the data on the longitudinal position of the pipe 1 as measurement results corresponding to a portion of the total measurement results (expanded view) and stores them in a memory area (step S34).

[0102] Here, it is determined whether the position of the sensor head 2 has reached the inspection end position (step S18).

[0103] If the inspection end position has not been reached, the process is repeated from step S11.

[0104] On the other hand, when the inspection end position is reached, image information is generated from the individual measurement results stored in a predetermined area so that a development (first image) of an image showing the thickness of each part in the circumferential and longitudinal directions of the pipe 1 can be compared with a development (second image) of an image showing each part in the circumferential and longitudinal directions of the inner surface of the pipe 1. Furthermore, the degree of deterioration is determined for each of the first and second images based on a predetermined determination standard (guideline) (step S19). The degree of deterioration is determined, for example, for each part (for example, for each individual area into which the inner surface of the pipe 1 is divided in advance), and also a comprehensive determination is made for the entire pipe.

[0105] According to the third embodiment, in image information obtained by integrating a development (first image) of an image showing the thickness of each part in the circumferential and longitudinal directions of the pipe 1 obtained from the results of transmitting and receiving ultrasonic waves by the multiple ultrasonic sensors 101 and a development (second image) of an image showing each part in the circumferential and longitudinal directions of the inner surface of the pipe 1 obtained from the results of imaging by the camera 102 using the wide-angle lens 107, the image information can be displayed on the display unit 6 or the like with information indicating the degree of deterioration or information calling attention added to each of the first image and the second image. This allows efficient pipe inspection by utilizing both the imaging of the inside of the pipe using the camera 102 and the measurement of the pipe thickness using the multiple ultrasonic sensors 101.

[0106] <Fourth embodiment> Next, a fourth embodiment will be described, focusing on the differences from the third embodiment.

[0107] (composition) FIG. 15A shows an example of the configuration of an inspection system according to the fourth embodiment, focusing on the sensor head 2. FIG. 15B shows an example of the structure of the sensor head 2 shown in FIG. 15A as viewed from the longitudinal direction of the pipe 1. Here, FIG. 1A will also be referenced as appropriate. The overall configuration of the inspection system according to the fourth embodiment is the same as that shown in FIG. 1A, except for the configuration of the sensor head 2.

[0108] The fourth embodiment differs from the third embodiment in that the sensor head 2 is provided with a conical mirror 108 instead of a wide-angle lens 107. The conical mirror 108 is disposed, for example, near the front end of the sensor head 2. The camera 102 is disposed near the conical mirror 108. C represents the field of view of the camera 102.

[0109] The camera 102 has a field of view P C The camera 102 captures an image of the area of ​​the wall of the pipe 1 that is reflected by the conical mirror 108. The conical mirror 108 makes it possible to capture an image of the inner surface of the entire circumference of the pipe 1. The image captured by the camera 102 is transmitted to the processor 7 of the information processing device in the ground device 5 via a cable C.

[0110] (Configuration of ground device 5) The configuration of the ground device 5 according to the fourth embodiment is similar to that shown in FIG.

[0111] In the third embodiment, the area of ​​the pipe 1 where each ultrasonic sensor transmits and receives ultrasonic waves for pipe thickness measurement and the area of ​​the pipe 1 imaged by the camera 102 are separated by a certain distance, and information on different areas is obtained at the same time. In contrast, in the fourth embodiment, the camera 102 can obtain information on the same area via the conical mirror 108 at the same time as the area where each ultrasonic sensor transmits and receives ultrasonic waves. This makes it easy to adjust the longitudinal position of the pipe 1 to be aligned between the first image and the second image.

[0112] (operation) The operation of the inspection system according to the fourth embodiment is similar to that shown in FIG. 14, and therefore a description thereof will be omitted.

[0113] According to the fourth embodiment, in image information obtained by integrating a development (first image) of an image showing the thickness of each part in the circumferential and longitudinal directions of the pipe 1 obtained from the results of transmitting and receiving ultrasonic waves by the multiple ultrasonic sensors 101 and a development (second image) of an image showing each part in the circumferential and longitudinal directions of the inner surface of the pipe 1 obtained from the results of imaging by the camera 102 using the conical mirror 108, the image information can be displayed on the display unit 6 or the like with information indicating the degree of deterioration or information calling attention added to each of the first image and the second image. This allows efficient pipe inspection by utilizing both the imaging of the inside of the pipe using the camera 102 and the measurement of the pipe thickness using the multiple ultrasonic sensors 101.

[0114] <Modification> Next, modifications of the third and fourth embodiments will be described.

[0115] FIG. 16 shows a modified example of the arrangement of the ultrasonic sensors applied to the third and fourth embodiments.

[0116] In the third and fourth embodiments, a plurality of ultrasonic sensors 101-1, 101-2, 101-3, 101-4, 101-5, and 101-6 are provided on the outer periphery of the sensor head 2, and are arranged at regular intervals in the circumferential direction. In this modification, each of the plurality of ultrasonic sensors 101-1, 101-2, 101-3, 101-4, 101-5, and 101-6 is configured as a further plurality of ultrasonic sensors 101-1a, 101-1b, 101-1c, ... 101-6a, 101-6b, and 101-6c, and each of the plurality of ultrasonic sensors 101-1a, 101-1b, 101-1c, ... 101-6a, 101-6b, and 101-6c is arranged to transmit ultrasonic waves in mutually different directions and receive the reflected waves thereof.

[0117] In other words, multiple ultrasonic sensors 101 are installed around the entire circumference of the sensor head 2, tilted in various directions, so that even if the center of the sensor head 2 is shifted from the center of the pipe 1, there will be an ultrasonic sensor that will emit ultrasonic waves that will hit the inner surface of the pipe almost perpendicularly.

[0118] The pipe thickness calculation unit 72 shown in Figure 13 obtains received waves from multiple ultrasonic sensors, but if the direction in which the ultrasonic waves hit the inner surface of the pipe 1 is significantly different from the perpendicular direction, no reflected waves will be obtained, so the thickness of the entire circumference of the pipe 1 can be measured without using this data.

[0119] According to this modification, in addition to the effects obtained in the third and fourth embodiments, it is possible to measure the thickness of the entire circumference of the pipe 1 even if the center of the sensor head 2 is shifted from the center of the pipe 1.

[0120] As described above in detail, at least one embodiment allows for efficient inspection of pipes.

[0121] Although several embodiments of the present invention have been described, these embodiments are presented as examples and are not intended to limit the scope of the invention. These novel embodiments can be embodied in various other forms, and various omissions, substitutions, and modifications can be made without departing from the spirit of the invention. These embodiments and their modifications are included within the scope and spirit of the invention, and are also included in the scope of the invention and its equivalents as defined in the claims. [Explanation of symbols]

[0122] 1...pipe, 2...sensor head, 3...position measuring device, 4...reel, 5...ground equipment, 6...display unit, 7...processor, 8...memory, 9...recording unit, 10...roller, 21...skid or tire, 71...rotation control unit, 72...pipe thickness calculation unit, 73...image integration unit, 74...deterioration determination unit, 75...image integration unit, 101...ultrasonic sensor, 102...camera, 103...motor, 104...mirror, 105...acceleration sensor, 106...laser rangefinder, 107...wide-angle lens, 108...conical mirror, 111...transmitting and receiving circuit, 113...motor drive circuit.

Claims

1. a plurality of ultrasonic sensors that transmit ultrasonic waves to various parts of the pipe in the circumferential direction and receive the reflected waves; An imaging device; an optical system that enables the imaging device to capture images of each portion of the inner surface of the pipe in the circumferential direction; and a sensor head that moves in the longitudinal direction of the pipe. a pipe thickness calculation unit that calculates the thickness of each portion of the pipe in the circumferential direction and the longitudinal direction from the results of transmission and reception by the plurality of ultrasonic sensors; an image integration unit that generates image information that combines a first image that represents the thickness of each portion of the pipe in the circumferential direction and the longitudinal direction calculated by the pipe thickness calculation unit and a second image that represents each portion of the inner surface of the pipe in the circumferential direction and the longitudinal direction obtained from the imaging results of the imaging device so that they can be compared; Equipped with each of the plurality of ultrasonic sensors is configured as a further plurality of ultrasonic sensors, and each of the plurality of ultrasonic sensors transmits ultrasonic waves in mutually different directions and receives reflected waves thereof; Inspection system.

2. The image integration unit generates the image information in a state in which information that allows the circumferential position and longitudinal position of the pipe to be confirmed is added to the image information. The inspection system of claim 1 .

3. a roller that contacts a cable connected to the sensor head, or a reel that winds the cable, or a tire that is provided on the sensor head; a position measuring device that measures a penetration length indicating a length of penetration of the sensor head in the longitudinal direction from a reference position within the pipe, based on the number of rotations of the roller, the number of rotations of the reel, or the number of rotations of the tire; Furthermore, The image integration unit recognizes the longitudinal position of the tube imaged by the imaging device using the information on the penetration length.

3. The inspection system according to claim 1 or 2.

4. a sensor head including a plurality of ultrasonic sensors, an imaging device, and an optical system member, the sensor head moving in the longitudinal direction of the pipe, the plurality of ultrasonic sensors transmitting ultrasonic waves to each portion of the circumferential direction of the pipe and receiving the reflected waves from the ultrasonic waves, the plurality of ultrasonic sensors being configured as a further plurality of ultrasonic sensors, each of the plurality of ultrasonic sensors transmitting ultrasonic waves in mutually different directions and receiving the reflected waves from the ultrasonic waves, the imaging device imaging each portion of the circumferential direction of the inner surface of the pipe via the optical system member; a pipe thickness calculation unit for calculating the thickness of each portion of the pipe in the circumferential direction and the longitudinal direction from the results of transmission and reception by the plurality of ultrasonic sensors; an image integration unit generates image information that combines a first image representing the thickness of each portion of the pipe in the circumferential direction and the longitudinal direction with a second image representing each portion of the inner surface of the pipe in the circumferential direction and the longitudinal direction obtained as a result of imaging by the imaging device so that the combined image information can be compared; 12. A testing method comprising:

Images