JP7634185B2 - Pipe Inspection System - Google Patents

Description

The present invention relates to a pipe inspection system that inspects pipes installed within a factory facility for leaks.

Factory sites are often vast, and pipes are often located outside the various buildings along the premises. Liquids often flow through these pipes, and leaks require prompt repair.

However, pipes are often located several meters above ground, and it is extremely rare for the bottom of a pipe to be at eye level. Therefore, with the past, pipe leaks could only be detected when liquid pooled on the ground below the pipe, or, in the case of smelly liquids, when there was an odor. Also, having people patrol a vast site to inspect the area was costly just for the inspections. This led to a demand for mechanizing leak inspections.

As an example of an invention that mechanically checks for leaks, Patent Document 1 discloses a device that checks for water leaks in the passenger compartment and luggage compartment of an automobile. In this device, infrared light is irradiated onto the symmetrical surface, and the reflected waves when there is no leak are stored as reference data, and the presence or absence of leaks is checked by comparing them with this reference data.

Japanese Patent Application Publication No. 11-160185

Patent Document 1 is capable of detecting minute water leaks, but it tests a relatively small area, and it takes too much time to test for leaks in pipes located across a large site.

The present invention was conceived in consideration of the above problems, and provides a pipe inspection system that can detect leaks in long pipes installed across a large site at an early stage.

More specifically, the pipe inspection system according to the present invention comprises:
1. A pipe inspection system for inspecting a pipe for liquid leaks, comprising:
A mobile object equipped with a light and a camera,
a control device in communication with the moving object;
The moving object moves along a set route,
The light is irradiated onto the pipe to be inspected, and when a bright spot is observed on the underside of the pipe by the camera, the position of the observed spot is recorded.

The pipe inspection system of the present invention is equipped with a light and a camera on a mobile body, and the light is shone on the pipe being inspected, and the position of the bright spot that is reflected by droplets that form on the underside of the pipe is recorded as the location of the leak, making it possible to mechanically inspect pipes across a large site for leaks and detect them early.

1 is a diagram showing a configuration of a pipe inspection system according to a first embodiment. FIG. 2 is a diagram showing the configuration of a first flying object. FIG. 2 is a diagram showing the configuration of a second flying object. FIG. 11 is a flow chart showing image processing performed by the second flying object. 2 is a diagram showing the positional relationship between a first flying body and a second flying body during flight. FIG. 13A to 13C are diagrams showing other positional relationships between the first and second flying bodies during flight. FIG. 11 is a flow chart showing the processing of the first flying object. FIG. 11 is a flow chart showing the process of inspecting the first flying object. 11A-11C are diagrams illustrating the movements of the first and second flying bodies when inspecting a coupling flange. FIG. 11 is a flow chart showing the processing of a second flying object. FIG. 4 is a flow chart showing the processing of the control device. FIG. 13 is a diagram showing the configuration of another embodiment of a pipe inspection system. FIG. 11 is a flow diagram showing the process when a squadron deviates from its flight route. FIG. 11 is a flowchart showing the process of a control device in another embodiment. FIG. 1 is a diagram illustrating a configuration of an autonomous vehicle. FIG. 1 illustrates an autonomous vehicle inspecting a pipe. FIG. 1 is a diagram showing the configuration of an autonomous vehicle equipped with an infrared camera.

The following is an explanation of the pipe inspection system 1 according to the present invention, with reference to the drawings. Note that the following explanation is merely an example of one embodiment of the present invention, and the present invention is not limited to the following explanation. The following explanation can be modified without departing from the spirit of the present invention.

In the present invention, in order to monitor for leaks in pipes arranged within a vast factory site, a mobile object is made to travel along a set route or along a set pipe for monitoring. Here, the mobile object may be an air vehicle (a mobile object that flies in the air) or an autonomous vehicle (that travels on land). Below, embodiments in the case of an air vehicle and an autonomous vehicle are described.

(Embodiment 1)
The pipe inspection system 1 according to this embodiment is a system for early detection of liquid leakage from piping installed in a factory. More specifically, when a liquid leakage occurs in a pipe, liquid droplets first accumulate on the bottom surface of the pipe. The pipe inspection system 1 detects the liquid droplets on the bottom surface of the pipe. In this embodiment, the moving body 9 will be described as an aircraft 10 and an aircraft 20.

Figure 1 shows the configuration of the pipe inspection system 1 of this embodiment. Figure 1 is a cross-sectional view perpendicular to the longitudinal direction of the inspected pipe 50, which is the object of inspection. The pipe inspection system 1 of this embodiment has a first flying object 10, a second flying object 20, a control device 30, and a base 40. The inspected pipe 50 is a pipe located outside a factory building. Generally, liquid is transported through the pipe. The pipe inspection system 1 of this embodiment inspects whether or not there is any liquid leakage at the joints of the pipe or in the middle of the pipe.

The first aircraft 10 and the second aircraft 20 fly on opposite sides of the inspected pipe 50. The first aircraft 10 and the second aircraft 20 are sometimes collectively referred to as a "flight squadron." The first aircraft 10 is equipped with a light 12. The second aircraft 20 is equipped with a camera 22. The first aircraft 10 illuminates the underside of the inspected pipe 50. The second aircraft 20 photographs the underside of the inspected pipe 50 from the opposite side of the inspected pipe 50.

If a liquid leak occurs in the inspected pipe 50, liquid droplets 55 will appear on the underside of the inspected pipe 50. The light 12L emitted by the light 12 from the first flying object 10 will then be refracted by the liquid droplets 55, and will be observed as bright spots 55F by the camera 22 of the second flying object 20. In particular, such liquid droplets 55 can often be observed on the underside of the connecting flange 50f at the joint between the pipes.

When the second flying object 20 observes a bright spot 55F on the underside of the inspected pipe 50, it records the observed position. The observed position here refers to the position of the second flying object 20 within the factory grounds when the droplet 55 was observed, but it may also be the position of the inspected pipe 50 where the droplet 55 was observed. In the pipe inspection system 1 according to this embodiment, it is important to detect leakage early, and the detailed location of the leakage and its repair are left to manual labor. Therefore, it is sufficient to know the approximate location where the droplet 55 was found.

When the second flying object 20 records the bright spot 55F, it wirelessly transmits the location information to the control device 30. However, in a factory where buildings and equipment are installed, real-time communication with the control device 30 installed at the base 40 may not be possible. Therefore, if it is not possible to contact the control device 30, the second flying object 20 simply needs to record the location information.

In the pipe inspection system 1 according to this embodiment, it is preferable for the first flying object 10 and the second flying object 20 to fly at night. This is because it is difficult to distinguish the bright spot 55F of light from the droplet 55 during the day.

＜Squadron＞
The configuration of the first flying body 10 is shown in Fig. 2, and the configuration of the second flying body 20 is shown in Fig. 3. In each figure, (a) is a plan view from above, (b) is a side view, and (c) is a front view. In (b), the arrow indicates the normal forward direction of travel. In the following explanation, common components are indicated by the same reference numerals. The flying bodies (10, 20) are composed of propellers (10a, 20a), housings (10d, 20d), and legs (10g, 20g).

The housing (10d, 20d) has a communication unit (10c, 20c), a battery (not shown), and a control unit (not shown). There are multiple propellers (10a, 20a), and their rotation is controlled by a motor (10b, 20b). A type that can hover in the air is preferable. This is because during the pipe inspection stage, it is necessary to hover and change altitude from that position.

The squadron will also have the means to obtain information about its position, direction, and altitude, since autonomous flight is not possible without such functionality. These means can utilize known methods and equipment.

The first flying object 10 is further equipped with a light 12. The central axis of the light's illumination is called the illumination axis 12ax. The light 12 is oriented perpendicular to the direction of travel, but it is desirable for the light 12 to be able to rotate and swing within a specified range of angles in the horizontal plane and in the elevation direction.

The light 12 may be white light, or light of a specific wavelength. Mercury lamps or LED lights are often used as illumination within the factory premises at night. These light sources often emit a specific wavelength. Therefore, by using light of a wavelength that is not used for illumination within the factory premises, it is possible to eliminate cases where the bright spot 55F observed by the second flying object 20 is caused by the lighting within the premises.

The aircraft may also have a forward light 14 that illuminates the direction of travel, a forward camera 16 that captures images of the front, and a side camera 18 that is parallel to the illumination axis 12ax. The inspected pipe 50 has a connecting flange 50f, and the first aircraft 10 and the second aircraft 20 must also change altitude at the connecting flange 50f. This is because the aircraft must detect the presence or absence of the connecting flange 50f ahead of the flight. If there is a side camera 18 that can capture images in the direction of illumination of the light 12, the underside of the inspected pipe 50 can be more reliably confirmed.

The second flying object 20 is equipped with a camera 22. When the first flying object 10 emits light of a specific wavelength, the camera 22 has a filter for that wavelength. The filter may be a physical filter, but may also be a digital filter that essentially identifies only that wavelength through image processing. The center of the lens of the camera 22 is called the optical axis 22ax.

The control unit (not shown) of the second flying object 20 also has an image processing unit (not shown) that processes the images captured by the camera 22. FIG. 4 shows the flow of processing by the image processing unit. When the image processing unit starts (step S100), it makes an end determination (step S102). The end determination may be made when the inspection is completed. For example, the inspection area is completed and the inspection area is moved to another area or the inspection area is returned to the base 40.

Note that an inspection section refers to one section when the area inspected by the pipe inspection system 1 is divided into multiple sections. Since the squadron flies on batteries, there is a limit to the flight time. Therefore, the area that can be flown on a single charge is used as the unit of inspection.

If it is to be terminated (Y branch of step S102), the process is terminated (step S104). If it is not to be terminated (N branch of step S102), the process is continued.

The image processing unit first imports the image captured by the camera 22 (step S106). Then, it performs binarization processing (step S108). By binarizing, dark areas such as the inspected pipe 50 and the background become black, and the droplet 55 part that collects the light irradiated by the first flying object 10 becomes a bright spot 55F (white).

Next, it is determined whether or not a bright spot 55F exists in the binarized image (step S110). Bright spots 55F may be determined to be those with a predetermined radius or greater.

If it is determined that a bright spot 55F is present (Y branch of step S110), the validity of the bright spot 55F being a droplet 55 is determined (step S112). As described below, the first and second flying bodies (10, 20) fly while maintaining a constant positional relationship with respect to the inspected pipe 50.

Therefore, it is possible to roughly determine where the inspected pipe 50 is located on the camera 22 of the second flying object 20. If the bright spot 55F is found near the bottom surface of the inspected pipe 50, it is determined to be a droplet 55. On the other hand, a bright spot 55F that appears in a position unrelated to the position of the inspected pipe 50 is determined to be noise.

If it is determined that the bright spot 55F is a droplet 55 (Y branch in step S112), the current position is recorded (step S114). This may be the position of the second flying object 20, or it may be the position of the inspected pipe 50 where the droplet 55 was observed.

If the bright spot 55F is not determined to be a droplet 55 (N branch in step S112), the process returns to the end determination (step S102).

Also, if it is determined that there is no bright spot 55F (N branch in step S110), the process returns to the end determination (step S102).

By repeating the above process, the second flying object 20 can search for the presence or absence of a bright spot 55F in the image captured by the camera 22.

<Flight formation>
The first and second flying bodies (10, 20) fly while maintaining a constant position relative to the inspected pipe 50. Fig. 5 shows the positional relationship of each flying body with respect to the inspected pipe 50. Fig. 5(a) shows a view of the inspected pipe 50 from below. The first and second flying bodies (10, 20) fly on opposite sides of the inspected pipe 50.

The first flying object 10 irradiates the light 12 toward the inspected pipe 50. On the other hand, it is desirable for the second flying object 20 to fly within an angle (θ) of ±10° with respect to the irradiation axis 12ax of the light 12 of the first flying object 10. If it deviates from this angle, it becomes difficult to observe the light passing through the droplets 55 of the irradiated light.

Figure 5 (b) shows the positional relationship from a cross-sectional direction perpendicular to the longitudinal direction of the inspected pipe 50. The first flying object 10 flies so that the illumination axis 12ax is in the same plane as the vicinity of the underside of the inspected pipe 50. Meanwhile, the second flying object 20 flies so that the optical axis 22ax of the camera 22 is in a position where it can observe the underside of the inspected pipe 50 from a height between the illumination axis 12ax and an angle (φ) of 10°.

The first and second flying bodies (10, 20) should fly so that they are both within the ranges θ and φ shown in Figures 5(a) and (b). As an example, referring to Figure 6, the first flying body 10 goes ahead and the second flying body 20 flies a predetermined distance DL behind. Since the inspected pipe 50 has a connecting flange 50f, it is necessary to change the altitude. This is because the first flying body 10 detects the approach to the connecting flange 50f and notifies the second flying body 20 to slow down.

The first flying body 10 and the second flying body 20 may be programmed in advance into a flight formation. However, errors occur in actual flight due to various factors. For this reason, it is desirable for them to be able to communicate with each other so that they can adjust their positions and speeds. The first flying body 10 transmits data regarding the current position (including altitude information), current speed, and the direction of the illumination axis 12ax to the second flying body 20. Meanwhile, the second flying body 20 can transmit its current position (including altitude), current speed, and the direction of the optical axis 22ax of the camera 22 to the first flying body 10.

The second flying object 20 may also transmit a signal to the first flying object 10 requesting it to decelerate if it is about to leave the detection range of the bright spot 55F from the light 12.

<Flight plan>
The pipe inspection system 1 according to the present embodiment enables early detection of liquid leakage from pipes by detecting liquid droplets 55 that appear on the underside of the pipe when a liquid leakage occurs. Usually, such liquid leakage occurs at the joint of the pipes (the joint flange 50f). However, when the pipes are arranged vertically, liquid leakage from the upper pipe drips onto the lower pipe, and as a result, liquid droplets 55 may appear on the underside of the lower pipe in places other than the joint flange 50f.

In addition, cracks in the pipe itself may cause liquid leakage in areas other than the connecting flange 50f. Therefore, it is desirable for the pipe inspection system 1 to also inspect the underside of the pipe and the underside of the connecting flange 50f.

However, the connecting flange 50f is larger than the outer diameter of the pipe. Therefore, the first and second aircraft (10, 20) need to change their flight altitude. The position of the connecting flange 50f may be given in advance, or the first aircraft 10 may discover it by itself.

Figure 7 shows a processing flow for the inspection flight of the first flying object 10. The pipe inspection system 1 is assumed to have received position information required for inspection, such as the position of the pipe 50 to be inspected and a map of the premises, input in advance from the control device 30. The first and second flying objects (10, 20) fly on batteries, so the range they can fly on a single charge is fixed. Therefore, the range within the factory premises that will be inspected at one time is determined in advance. This range is called the "inspection section."

When the process is started (step S200), a termination determination is made (step S202). The criteria for the termination determination may be the end of the inspection section or an emergency situation. If the process is to be terminated (Y branch in step S202), the process returns to base 40 and ends (step S204). If the process is to be continued (N branch in step S202), the process moves to the next flow.

Then, the aircraft flies to the inspection section within the premises (step S206). The flight to the inspection section follows a predetermined route. Once the aircraft has flown to the inspection section, preparations for inspection are made (step S208). Preparations for inspection include checking that the lights 12 are on and that the aircraft and the second aircraft 20 have arrived at the designated positions.

Next, the inspection begins (step S210). The first flying object 10 flies along the pipe 50 to be inspected while illuminating the underside of the pipe 50 with light from the light 12. The inspection steps are explained in detail in FIG. 8. When the inspection is completed, the process returns to the end determination (step S202) and determines whether or not there is a next inspection section.

Figure 8 shows the inspection process (step S210) in detail. When the inspection starts, the first aircraft 10 flies along the pipe 50 to be inspected while illuminating the underside of the pipe 50 with the light 12. It is then determined whether or not a change in altitude occurs after a predetermined time (step S252). A change in altitude may occur when the piping of the pipe 50 to be inspected changes in the vertical direction, or when a connecting flange 50f is present or absent. This determination may be made using the forward camera 16 mounted on the first aircraft 10, or may be incorporated in advance as a flight plan.

If there is no change in altitude (N branch of step S252), it is determined whether the current inspection section has ended (step S254). If it has not ended (N branch of step S254), the process returns to step S252 and the flight (inspection) continues.

If the current inspection section has ended (Y branch in step S254), the inspection process (step S210) is exited (step S256).

If there is an elevation change (Y branch in step S252), it is determined whether the elevation change is due to the connecting flange 50f or the piping arrangement (step S260). Here, the case due to the connecting flange 50f is represented by "F" and the elevation change due to the piping arrangement is represented by "A".

The movements of the first flying body 10 and the second flying body 20 at this time are shown in FIG. 9. Refer to FIG. 9 below as well. In the case of the connecting flange 50f (the flange (F) branch of step S260), communication is made to the second flying body 20, and the flying body stops in front of the connecting flange 50f at a constant acceleration and lowers its altitude (step S262, FIGS. 9(a) and (b)).

After confirming that the second aircraft 20 has reached the designated position, a start signal is sent to the second aircraft 20, and only the second aircraft 20 moves forward until it passes the connecting flange 50f (step S264, position 20' in Figure 9(b)). After that, both aircraft increase their altitude again (step S266, Figure 9(c)). After confirming that the second aircraft 20 has reached the designated position, only the first aircraft 10 moves forward a designated distance DL (step S268, Figure 9(d)). After that, both aircraft move forward and resume inspection of the underside of the inspected pipe 50 (pipe body 50b) (step S270, Figure 9(e)).

On the other hand, if the altitude change is due to piping (branch A of step S260), the altitude change rate is notified to the second aircraft 20 (step S272), and the flight (inspection) continues.

Next, the processing flow of the second aircraft 20 is explained in FIG. 10(a). The overall flow is almost the same as the processing flow of the first aircraft 10 in FIG. 7.

When processing is started (step S300), a termination determination is made (step S302). The criteria for the termination determination may be termination due to the end of the inspection section or an emergency situation. If processing is to be terminated (Y branch in step S302), the process returns to base 40 and terminates (step S304). If processing is to be continued (N branch in step S302), the process moves to the next flow.

Then, the second flying body 20 flies to the inspection section within the premises (step S306). The flight to the inspection section follows a predetermined route. Once the second flying body 20 has flown to the inspection section, preparations for the inspection are made (step S308). In preparation for the inspection, the second flying body 20 is positioned at a predetermined altitude on the opposite side of the first flying body 10, across the pipe 50 to be inspected. The optical axis 22ax of the camera 22 is also aligned with the underside of the pipe 50 to be inspected. Then, when preparations are complete, the first flying body 10 is notified that preparations are complete.

Next, the inspection begins (step S310). When a notification of the start of the inspection is received from the first flying object 10, the flying object increases its speed at a predetermined acceleration rate and flies while photographing the underside of the pipe 50 to be inspected with the camera 22 and inspecting whether or not a bright spot 55F appears on the underside of the pipe 50 to be inspected.

Here, it is preferable for the second flying body 20 to fly at a position behind the first flying body 10 in the direction of travel. This is because the first flying body 10 decelerates just before the connecting flange 50f, and the second flying body 20 must follow that movement. If the second flying body 20 flies behind the first flying body 10, it can also follow the deceleration of the first flying body 10 to a large extent. Once the inspection is completed, return to the end judgment (step S302) and judge whether there is a next inspection section.

Figure 10(b) details the process corresponding to the inspection step (step S310) of the second flying object 20. When the inspection starts, the second flying object 20 flies on the opposite side of the first flying object 10, sandwiching the pipe 50 to be inspected, while taking an image of the underside of the pipe 50 to be inspected with the camera 22.

During flight, the system attempts to find bright spot 55F by image analysis according to the flowchart shown in FIG. 4. Then, it is determined whether an altitude change will occur after a predetermined time (step S352). The altitude change may be determined by a notification from first flying object 10, or may be incorporated in advance as part of the flight plan.

If there is no change in altitude (N branch of step S352), determine whether the current inspection section has ended (step S354). If it has not ended (N branch of step S354), return to step S352 and continue the inspection flight.

If the current inspection section has ended (Y branch in step S354), the inspection process (step S310) is exited (step S356).

If there is a change in altitude (Y branch in step S352), the second aircraft 20 follows the instructions in the notification from the first aircraft 10 (step S360). This is because the second aircraft 20 checks for the presence or absence of a bright spot 55F while moving in accordance with the movement of the first aircraft 10. In other words, while flying along the course indicated by the first aircraft 10, the camera 22 photographs the inspected pipe 50 and performs the image processing shown in Figure 4 to check for the presence or absence of a bright spot 55F.

＜Base＞
Referring again to Fig. 1, the first and second flying bodies (10, 20) take off from a base 40 and return to the base 40. The base 40 has at least a charging facility 40a and a data transfer facility (not shown). The control device 30 may be installed in the base 40 or may be installed in another location. Here, it is assumed that the control device 30 is installed in the base 40.

The base 40 is equipped with a clock, an anemometer, and a rain gauge (not shown). The pipe inspection system 1 according to this embodiment cannot perform inspections on rainy days because it is not possible to distinguish between liquid leaks and raindrops. Also, if the wind is too strong, it is difficult for the aircraft to fly at all.

The base 40 stores at least two flying vehicles and charges the batteries of each flying vehicle. It also transfers map information of the planned inspection area and data related to the bright spot 55F acquired by the second flying vehicle 20 to the control device 30. The operation of the base 40 may be performed by the control device 30.

<Control device>
The control device 30 controls the operation of the base 40, issues instructions to the first aircraft 10 and the second aircraft 20, and collects data. The control device 30 is equipped with an MPU (Micro Processor Unit) 30a, a controller 30r, a display 30d, and a communication device 30c. In the pipe inspection system 1 according to the present embodiment, the aircraft flies autonomously, but may also be inspected by a human. In that case, the controller 30r is used. The control device 30 may be a mobile terminal itself, or may be configured to include a fixed station and a mobile terminal.

Figure 11 shows the processing flow of the control device 30. Once processing has started (step S400), an end determination is made (step S402). The end determination may be based on an end instruction from a person or end determined by a program.

If the process is to end (Y branch at step S402), the data is backed up and the process ends (step S404). If the process is to continue (N branch at step S402), the process proceeds to the next flow.

In the next flow, the scheduled inspection time is confirmed (step S406). The inspection schedule for the pipe inspection system 1 is determined in advance. For example, the inspection schedule may be to inspect all pipes every day, inspect all pipes every other day, or inspect all pipes on the site in three days.

Also, if two aircraft make up one formation, multiple formations can be used to divide the site into sections, and each section can be inspected by a separate formation. In this case, the control device 30 is input with times associated with the inspection, such as the charging start time for each formation, the departure time, and the scheduled return time.

Therefore, the control device 30 is in a waiting state until the scheduled time arrives. When the scheduled time arrives (Y branch of step S406), the weather is checked (step S408). This is because the inspection cannot be carried out if it is raining. Therefore, if it is raining even when the scheduled time arrives (N branch of step S408), it is decided to postpone the inspection (step S410), and the process returns to step S402.

If it is not raining (Y branch in step S408), a departure command is issued to the first aircraft 10 and the second aircraft 20 (step S412). This causes the first and second aircraft (10, 20) to begin their inspection flight. If communication with the squadron is possible, the current location of the squadron is monitored.

After the squadron departs, the system goes into a waiting state until it returns (step S414). Also, if communication with the squadron is possible, information from the second flying object 20 (the location where the bright spot 55F was found) is received and recorded together with the time.

After the squadron returns (Y branch in step S414), if the inspection information has not been acquired in real time, the inspection data is collected from the second flying object 20 (step S416). The control device 30 then edits the position and image data of the bright spot 55F observed by the squadron into a specified format, outputs the data, and returns the process to S402.

In addition, to determine whether or not a leak has actually occurred and whether repairs are necessary, it is best for a person to go to the location and check with the naked eye, as identifying the location of the leak and repairing it requires skill. However, manually inspecting pipes located within a vast factory site for initial leak locations takes a lot of time, whereas the pipe inspection system according to this embodiment allows for automatic inspections using drones at night, which contributes ideally to piping maintenance.

(Embodiment 2)
In the first embodiment, the second flying object 20 inspects for liquid leakage by detecting, as a bright spot 55F, the illumination from the first flying object 10 passing through the droplets 55 generated in the inspected pipe 50. However, the inspected pipe 50 is placed outdoors, and depending on the windy area or the layout of buildings within the factory site, the flying object may be blown by the wind near the inspected pipe 50, and the flying object may not fly the set route accurately.

Figure 12 shows the case where the second flying object 20 is blown by the wind and goes outside the area where the bright spot 55F can be photographed. The dotted line shows the second flying object 20 going off course downward.

The pipe inspection system 2 according to this embodiment can detect liquid leakage from the inspected pipe 50 even in such a situation. Note that the configuration and technical ideas described in embodiment 1 that can be applied to this embodiment are applicable even if not described.

In the pipe inspection system 2 of this embodiment, the elements constituting the system are the same as those shown in FIG. 1 of the first embodiment. However, the control device includes new processes, so it is called the control device 32. Therefore, the control device 32 is equipped with an MPU (Micro Processor Unit) 32a, a controller 32r, a display 32d, and a communication device 32c.

In the pipe inspection system 2 of this embodiment, the light 12 mounted on the first flying object 10 emits infrared light, and the side camera 18 is also equipped with an infrared camera. In addition, the camera 22 on the second flying object 20 is equipped with a camera 22 that can receive infrared light.

In the pipe inspection system 2 of this embodiment, the first flying object 10 emits infrared light from the light 12 and captures the underside of the inspected pipe 50 with the side camera 18. The operation of the second flying object 20 is the same as in the first embodiment. By receiving the infrared light 12Lr from the first flying object 10, the droplets 55 are captured as luminance 55F, and it is determined whether or not there is a water leak.

On the other hand, if the second flying object 20 strays from its course or is blown off course by the wind, a leak is determined based on the images captured by the first flying object 10. More specifically, for sections that the second flying object 20 was unable to inspect, the presence or absence of a leak is determined based on the infrared images captured by the first flying object 10 during the previous inspection.

Figure 13 shows the processing applied to the first aircraft 10 and the second aircraft 20. Other than the processing shown in Figure 13, the first aircraft 10 follows the flow shown in Figures 7 and 8, and the second aircraft 20 follows the flow shown in Figure 10. Note that Figure 13 may be inserted anywhere in the processing flow of the first aircraft 10 and the second aircraft 20, and may also be processing that is constantly executed in a separate routine.

For example, for the first flying object 10, it is preferable to insert it immediately after the inspection in FIG. 7 (step S210) (before step S252), and for the second flying object 20, it is preferable to insert it immediately after the inspection in FIG. 10(b) (step S310) (just before returning from step S360). Also, it may be included in the inspection in FIG. 8 (step S210) and step S360 in FIG. 10(b), respectively.

Referring to FIG. 13, when the process starts (step S500), it is determined whether or not there has been a change in flight conditions (step S502). A change in flight conditions refers to a deviation from the determined flight route (direction and altitude) beyond a predetermined range. It may also include a deviation in the relative positions between the two aircraft.

If the flight route is deviated from (Y branch in step S502), the route is corrected (step S504). This is controlled by a controller installed in each flying object. The route is corrected until it is possible to correct it (step S504).

Once the correction is complete (Y branch of step S506), the range of deviation from the route (hereafter referred to as the "deviation range Ro") is recorded, and this process is terminated (step S510). Also, if there is no change in the flight state in step S502 (N branch of step S502), this process is similarly terminated (step S510). The above process is performed in both the first flying body 10 and the second flying body 20.

Next, the processing of the control device 32 of the pipe inspection system 2 will be described. The processing of the control device 32 is almost the same as the processing of the control device 30 of the first embodiment shown in FIG. 11. However, the pipe inspection system 2 anticipates that there may be sections where the squadron is unable to inspect, and therefore it is necessary to collect and analyze data after the squadron returns to base.

14 shows detailed processing of data collection (step S416) in the pipe inspection system 2. When data processing (step S416) begins, the recorded data of the first flying body 10 and the second flying body 20 is downloaded (step S600). The recorded data includes the position where the bright spot 55F was observed, the infrared image IR _k recorded by the first flying body 10, the deviation range Ro, as well as data such as the flight route and date and time. Here, " _k " is a subscript that indicates the order of measurement.

Next, it is checked whether or not the deviation range Ro has been recorded (step S602). If there is no deviation range Ro (N branch in step S602), the position where the bright spot 55F was observed is selected (step S604). Here, selecting means making it possible to output (step S614).

If there is a deviation range Ro (Y branch in step S602), a comparison is made to see whether the temperature range TR _k that is different from the surroundings in the infrared image IR _k captured by the side camera 18 of the first flying body 10 is larger than the temperature range TR _k-1 that is different from the surroundings in the infrared image IR _k-1 acquired during the previous flight (step 608).

Since the location where the liquid leakage has occurred has a different temperature distribution from the surroundings, it can often be found by using an infrared camera. However, the temperature range may be low for other reasons. Therefore, the purpose of this method is to determine whether or not a liquid leakage has occurred by comparing the parts TR that have a different temperature distribution from the surroundings, which are shown in the previously measured infrared image IR _k-1 and the current infrared image IR _k .

If the temperature range TR _k different from the surroundings is larger than TR _k-1 (Y branch in step S608), it is determined that there is a high possibility that a liquid leak has occurred (step S612). On the other hand, if the temperature range TR _k different from the surroundings is equal to or smaller than TR _k-1 (N branch in step S608), it can be determined that a liquid leak has not occurred (step S610). These results are then output (step S614) and the routine ends (step S616).

As described above, if there is an area where the first flying body 10 and the second flying body 20 cannot jointly inspect, the presence or absence of leakage can be determined from images taken by the side camera 18 (infrared camera) mounted on the first flying body 10.

(Embodiment 3)
In the first and second embodiments, the mobile body 9 has been described using examples of multiple flying bodies 10 and 20, but in the pipe inspection system 3 of this embodiment, an example of one ground-based autonomous vehicle will be described as the mobile body 9. Compared to flying bodies, autonomous vehicles have the advantage of being able to carry large-capacity batteries and have longer running times, and one vehicle can be equipped with devices with various functions.

This embodiment can be applied when the underside of a pipe, where early detection of leaks is necessary, can be directly seen from the ground, and can also be applied indoors, where this is difficult for aircraft.

Note that the configurations and technical ideas described in embodiments 1 and 2 that can be applied to this embodiment are applicable even if not specified.

When the autonomous vehicle is on its patrol and arrives at a pipe inspection position where early detection of leaks is required, the light shines light onto the underside of the pipe and the camera takes an image of the underside of the pipe. The image is sent in real time to a control device with which the autonomous vehicle communicates, and the presence or absence of bright spots caused by leaks is determined by an image processing unit. If communication is not possible, the autonomous vehicle may be equipped with an image processing unit. The light irradiation diameter can be set as desired, but for example, in the case of a 2m diameter, the light can be shined on and the camera can be photographed every 2m, making it possible to automatically inspect the entire length of the pipe for leaks.

In addition, adjustments to the elevation angles of lights and cameras in response to horizontal and vertical bends in the pipe are stored in a control unit inside the vehicle or in a control device outside the vehicle during prior test runs.

<Autonomous vehicles>
FIG. 15 shows the configuration of the autonomous vehicle 60. FIG. 15(a) is a plan view from above, FIG. 15(b) is a side view, and FIG. 15(c) is a front view. FIG. 15(d) shows the control device 70. In FIG. 15(a) and FIG. 15(b), the normal forward direction is indicated by an arrow. The autonomous vehicle 60 has a substantially rectangular parallelepiped pedestal 64 on the upper surface of a four-wheel drive vehicle body 63 having four tires 63a, and is provided with a rotating platform 66 on the top surface of the pedestal 64. The rotating platform 66 can rotate 360 degrees horizontally, and a light 61 and a camera 62 are attached to both sides of the rotating platform 66. The light 61 and the camera 62 can rotate 90 degrees vertically.

The vehicle body 63 has a communication unit (not shown), a battery (not shown), and a control unit (not shown). It is also equipped with a 3D laser sensor, allowing it to create a route map and travel autonomously.

Referring to FIG. 16, an autonomous vehicle 60 travels next to or diagonally below the inspected pipe 50. The autonomous vehicle 60 is equipped with a light 61 and a camera 62. The autonomous vehicle 60 illuminates the underside of the inspected pipe 50 and captures an image of the underside of the inspected pipe 50.

If a liquid leak occurs in the inspected pipe 50, liquid droplets 55 will appear on the underside of the inspected pipe 50. When this happens, the light 61L emitted by the light 61 from the autonomous vehicle 60 is refracted by the liquid droplets 55, and is observed by the camera 62 as a bright spot 55F. In particular, such liquid droplets 55 can often be observed on the underside of the connecting flange 50f at the joint between the pipes.

When the autonomous vehicle 60 observes a bright spot 55F on the underside of the inspected pipe 50, it records the observed position. The observed position here refers to the position of the autonomous vehicle 60 within the factory grounds when the droplet 55 is observed, but it may also be the position of the inspected pipe 50 where the droplet 55 is observed. In the pipe inspection system 3 according to this embodiment, it is important to detect leakage early, and the detailed location of the leakage and its repair are left to manual labor. Therefore, it is sufficient to know the approximate location where the droplet 55 was found.

When the autonomous vehicle 60 records the bright spot 55F, it wirelessly transmits the location information to the control device 70. However, in a factory where buildings and equipment are installed, real-time communication with the control device 70 installed at the base 80 (see FIG. 15(b)) may not be possible. Therefore, if it is not possible to contact the control device 70, the autonomous vehicle 60 simply needs to record the location information.

The processing flow for the inspection drive of the autonomous vehicle 60 is the same as that shown in Figure 7. Referring to Figure 7, the pipe inspection system 3 is assumed to have received position information required for inspection, such as the position of the inspected pipe 50 and a map of the premises, input in advance from the control device 70. Since the autonomous vehicle 60 runs on a battery, the range it can travel on a single charge is fixed. Therefore, the range within the factory premises that will be inspected at one time is determined in advance. This range is called the "inspection section."

When the process is started (step S200), an end determination is made (step S202). The end determination criteria may be the end of the inspection section or an emergency. If the process is to be ended (Y branch in step S202), the process returns to the base 80 and ends (step S204). If the process is to be continued (N branch in step S202), the process moves to the next flow.

Next, the vehicle travels to the inspection section within the premises (step S206). The vehicle travels along a predetermined route to the inspection section. Once the vehicle has reached the inspection section, preparations for the inspection are made (step S208). Preparations for the inspection are made by turning on light 61.

Next, the inspection begins (step S210). The autonomous vehicle 60 illuminates the underside of the inspected pipe 50 with light from the light 61, takes pictures with the camera 62 at predetermined intervals, and attempts to find bright spots 55F through image analysis according to the flowchart shown in FIG. 4, while traveling along a preset patrol route. When the inspection is complete, the process returns to the end determination (step S202), and determines whether or not there is a next inspection section.

＜Base＞
15(b) again. The autonomous vehicle 60 starts from the base 80 and returns to the base 80. The base 80 has at least a charging facility 80a and a data transfer facility (not shown). The control device 70 may be provided at the base 80 or may be installed at another location. Here, it is assumed that the control device 70 is provided at the base 80.

The base 80 stores at least the autonomous vehicle 60 and charges the battery of the autonomous vehicle 60. It also transfers map information of the section to be inspected and data related to the bright spot 55F acquired by the autonomous vehicle 60 to the control device 70. The operation of the base 80 may be performed by the control device 70. As shown in FIG. 15, it may be in the form of a stage.

<Control device>
The control device 70 operates the base 80, issues instructions to the autonomous vehicle 60, and collects data. The control device 70 is equipped with an MPU (Micro Processor Unit) 70a, a controller 70r, a display 70d, and a communication device 70c. In the pipe inspection system 3 according to this embodiment, the autonomous vehicle 60 runs autonomously, but may also run for inspection under human control. In that case, the controller 70r is used. The control device 70 may be a mobile terminal itself, or may be configured to include a fixed station and a mobile terminal.

The processing flow of the control device 70 is the same as that shown in FIG. 11 in the first embodiment. When the processing starts (step S400), an end determination is made (step S402). The end determination may be based on an end instruction from a person or end determined by a program.

If the process is to end (Y branch at step S402), the data is backed up and the process ends (step S404). If the process is to continue (N branch at step S402), the process proceeds to the next flow.

In the next flow, the scheduled inspection time is confirmed (step S406). The inspection schedule for the pipe inspection system 3 is determined in advance. For example, the inspection schedule may be to inspect all pipes every day, to inspect all pipes every other day, or to inspect all pipes on the site in three days.

In addition, multiple autonomous vehicles 60 may be used to divide the site into sections, and each section may be inspected by a different autonomous vehicle 60. In this case, the control device 70 is input with times associated with the inspection, such as the charging start time for each autonomous vehicle 60, the departure time, and the scheduled return time.

Therefore, the control device 70 is in a waiting state until the scheduled time arrives. When the scheduled time arrives (Y branch of step S406), if the inspection location is outdoors, the weather is checked (step S408). This is because the inspection cannot be performed if it is raining. Therefore, if it is raining even when the scheduled time arrives (N branch of step S408), it is decided to postpone the inspection (step S410), and the process returns to step S402. If the inspection location is indoors, checking the weather (step S408) can be skipped.

If it is not raining (Y branch in step S408), a departure command is issued to the autonomous vehicle 60 (step S412). This causes the autonomous vehicle 60 to start traveling for the inspection. After the autonomous vehicle 60 departs, it enters a waiting state until it returns (step S414).

After the autonomous vehicle 60 returns (Y branch in step S414), if the inspection information has not been acquired in real time, the inspection data is collected from the autonomous vehicle 60 (step S416). The control device 70 then edits the position and image data of the bright spot 55F observed by the autonomous vehicle 60 into a specified format, outputs the data, and returns the process to S402.

In addition, to check whether a leak has actually occurred and whether repairs are necessary, it is best for a person to go to the location and check with the naked eye, as identifying the location of the leak and repairing it requires skill. However, manually inspecting pipes located within a vast factory site for initial leak locations takes a lot of time, whereas the pipe inspection system according to this embodiment allows automatic inspection both indoors and outdoors using an autonomous vehicle 60, which contributes ideally to piping maintenance.

(Embodiment 4)
In the pipe inspection system 4 of the present embodiment, the system components are different from those shown in FIG. 15 of the third embodiment in that there is no light and an infrared camera is installed as the camera.

Referring to FIG. 17, in the pipe inspection system 4 of this embodiment, the autonomous vehicle 90 photographs the underside of the inspected pipe 50 with an infrared camera 91. The autonomous vehicle 90 judges whether there is a leak based on the image photographed. More specifically, the autonomous vehicle 90 judges whether there is a leak based on the infrared image photographed during the previous inspection. If the control unit of the autonomous vehicle 90 stores the infrared image photographed during the previous inspection, or if communication is possible between the autonomous vehicle 90 and the control device 92, the autonomous vehicle 90 can judge whether there is a leak during the inspection and can also record the location of the leak. In FIG. 17, the same elements as those in the third embodiment (FIG. 15) are denoted with the same reference numerals. The explanation is the same as that in the third embodiment, and may be omitted.

Next, the processing of the control device 92 of the pipe inspection system 4 will be described. The control device 92 is equipped with an MPU (Micro Processor Unit) 92a, a controller 92r, a display 92d, and a communication device 92c. The processing of the control device 92 is almost the same as the processing of the control device 30 of the first embodiment shown in FIG. 11.

Specifically, the same process as when there is a deviation range Ro in Fig. 14 (Y branch in step S602) is performed. That is, a comparison is made to see whether a temperature range TR _k different from the surroundings in an infrared image IR _k captured by the infrared camera 91 of the autonomous vehicle 90 is larger than a temperature range TR _k-1 different from the surroundings in an infrared image IR _k-1 acquired during the previous drive (step 608).

Since the location where the liquid leakage has occurred has a different temperature distribution from the surroundings, it can often be found by using an infrared camera. However, the temperature range may be low for other reasons. Therefore, the purpose of this method is to determine whether or not a liquid leakage has occurred by comparing the parts TR that have a different temperature distribution from the surroundings, which are shown in the previously measured infrared image IR _k-1 and the current infrared image IR _k .

If the temperature range TR _k different from the surroundings is larger than TR _k-1 (Y branch in step S608), it is determined that there is a high possibility that a liquid leak has occurred (step S612). On the other hand, if the temperature range TR _k different from the surroundings is equal to or smaller than TR _k-1 (N branch in step S608), it can be determined that a liquid leak has not occurred (step S610). These results are then output (step S614) and the routine ends (step S616).

As described above, the self-driving vehicle 90 is equipped with only an infrared camera 91, without the light 61 of embodiment 3, and can determine whether or not there is a leak from the captured infrared image.

The pipe inspection system of the present invention can be ideally used for automatically inspecting pipes installed in a factory for leaks.

1 Pipe inspection system 2 Pipe inspection system 3 Pipe inspection system 4 Pipe inspection system 10 First flying object 12 Light 12Lr Infrared light 12ax Irradiation axis 22ax Optical axis 12L Irradiation light 14 Forward light 16 Forward camera 18 Side camera 20 Second flying object 22 Camera 30 Control device 32 Control device 30r Controller 30d Display 30c Communication device 40 Base 50 Inspected pipe 50b Pipe body 50f Joint flange 55 Droplet 55F Bright spot DL Predetermined distance Ro Deviation range IR _k Infrared image TR _k Temperature range different from the surroundings 60 Autonomous vehicle 61 Light 62 Camera 63 Vehicle body 64 Base 70 Control device 80 Base 90 Autonomous vehicle 91 Infrared camera 92 Control device

Claims (5)

1. A pipe inspection system for inspecting a pipe for liquid leaks, comprising:
A mobile object equipped with a light and a camera,
a control device in communication with the moving object;
The moving object moves along a set route,
A pipe inspection system characterized in that the light is applied to a pipe to be inspected, and when a bright spot is observed on the underside of the pipe by the camera, the observed position is recorded. The moving body is
It is composed of a first flying vehicle carrying a light and a second flying vehicle carrying a camera.
a controller in communication with the first air vehicle and the second air vehicle;
The first flying body and the second flying body fly along a pipe to be inspected,
The first flying object irradiates the inspected pipe with light from the light,
2. The pipe inspection system according to claim 1, wherein the second flying object records the observed position when a bright spot is observed on the underside of the pipe by the camera. The first flying vehicle; and
3. The pipe inspection system according to claim 2, wherein the second flying object flies on the opposite side of the pipe to be inspected. The light emits light of a specific wavelength,
4. The pipe inspection system according to claim 1, wherein the camera has a filter that passes light of the specific wavelength. The specific wavelength is a wavelength in the infrared region,
The pipe inspection system according to claim 4, which cites claim 2 or 3, characterized in that the first flying object is equipped with an infrared camera that photographs the range illuminated by the light.