JP2007046944A - Remote visual inspection method, and self-travel type imaging device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a remote visual inspection method and a self-travel type imaging device capable of facilitating visual inspection in a place difficult to be approached, such as an under part of a nuclear reactor pressure vessel. <P>SOLUTION: When inspecting visually a housing 2 for a control rod driving mechanism of the nuclear reactor pressure vessel 1, the self-travel type imaging device 10 mounted with a video camera is laid on a nuclear reactor pressure vessel lower part heat insulator 3, an image picked up by the self-travel type imaging device 10 is transmitted to a controller 21 of a visual inspection part 20 located in a position distant from the nuclear reactor pressure vessel 1 to be displayed in a monitor 22, the visual inspection is carried out therein by an operator P, and a self-travel position of the self-travel type imaging device 10 is controlled via the controller 21, based on the image displayed in the monitor 22. The self-travel type imaging device 10 is constituted of three wheels comprising two driving side wheels and one auxiliary side wheel to regulate shaft weight balance by a balance weight, and an obstacle can get over with a small driving source to secure mobility in a narrow part. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a remote visual inspection method using a video camera and a self-propelled imaging apparatus used for the method, and more particularly to a method suitable for remote visual inspection of a lower part of a reactor pressure vessel and a self-propelled imaging apparatus.

  For visual inspection of places where humans are difficult to approach environmentally and spatially, such as the lower part of the reactor pressure vessel, a method has been used in which a video camera is remotely operated to approach the inspection object and the captured image is monitored. ing.

  At this time, in a certain prior art, a CCD camera is attached to the tip of a rod (rod member), and imaging is performed by remote control with the rod so that the inspection target part can be confirmed and inspected (for example, non-patent) Reference 1).

In another conventional technique, a self-propelled camera device in which a CCD camera is mounted on a self-propelled movable carriage so as to be close to an inspection object has been used for visual inspection inside a pipe (for example, (Refer nonpatent literature 2.).
"CA-ZOOM PAN-TILT-ZOOM System" catalog made by Everest VIT Catalog of "TV camera device pv-2000 for in-pipe inspection" manufactured by Kew Eye Co.

  The above prior art has a problem that it does not consider the operability of the video camera and requires a lot of work.

  In the case of the prior art using the rod, visual inspection by remote control of the camera is possible, but it takes a lot of labor and time to operate and inspect the rod, especially when the rod is in a horizontal state. There was a problem that it took time.

  Also, in the case of the prior art using a self-propelled camera device, the self-propelled device is a caterpillar drive type or a multi-wheel drive type, so the structure becomes complicated, and the size becomes large and a small turn in a narrow part In addition to being difficult, it is difficult to reduce the weight, and there is a problem that the running surface with poor rigidity may damage the running surface due to the weight of the device itself.

  An object of the present invention is to provide a remote visual inspection method and a self-propelled imaging device that can easily obtain a visual inspection in a place where environmental and spatial access is difficult such as a lower part of a reactor pressure vessel. is there.

  The object is to take images of the inspected sites at a plurality of locations with a video camera mounted on the moving means, and to monitor the inspected sites at the plurality of locations with a monitor at a remote location of the image captured by the video camera. In the remote visual inspection method in which a visual inspection is performed, a three-wheeled self-propelled means having two driving wheels and one auxiliary wheel is used as the moving means and is mounted on the self-propelled means. By monitoring an image captured by a video camera at a remote location, at least one of confirmation of the region to be inspected, position control of the self-propelled means, and control of the imaging direction by the video camera, and visual inspection of the region to be inspected Inspection is accomplished as obtained at the remote location.

  At this time, using a marker arranged in the vicinity of the inspection target region, the position confirmation of the self-propelled means may be given from a monitor of an image obtained by imaging the marker. The position of the self-propelled means may be confirmed by radio wave access to the IC chip.

  Similarly, the object is to make the main body frame in which the two driving wheels and one auxiliary wheel are arranged in a substantially triangular shape, and the axle position of the two driving wheels to be located directly below the overall center of gravity. The balance weight provided on the main body frame and one side in a direction perpendicular to the axle of the two driving wheels are positioned on one side and the other in a direction substantially parallel to the axle. A forward overturn prevention member attached to the lower side of the main body frame, and positioned on one side and the other in a direction substantially parallel to the axle on the other side perpendicular to the axle of the two driving wheels. A left-right fall prevention member attached to the lower side of the main body frame, and remote control means for independently controlling the rotation direction and the number of rotations of the two driving wheels. Pan by frame remote control It is achieved by mounting a video camera provided with a capability and tilt function.

  According to the remote visual inspection method of the present invention, it is possible to confirm and inspect a site that is difficult for humans to approach environmentally and spatially in a short time and at a low cost even in a narrow place.

  Hereinafter, a remote visual inspection method and a self-propelled imaging device according to the present invention will be described in detail with reference to embodiments shown in the drawings.

  Here, FIG. 1 is an embodiment in which the method of the present invention is applied to the remote visual inspection of the lower part of the nuclear pressure vessel in a nuclear power plant using the self-propelled imaging apparatus according to the present invention. 1 shows a reactor pressure vessel 1, a control rod drive mechanism housing 2, and a heat insulating material (reactor pressure vessel lower heat insulating material) 3.

  At this time, as shown in more detail in FIG. 2, the control rod drive mechanism housing 2 is arranged in the lower mirror part of the reactor pressure vessel 1 at equal intervals. These control rod drive mechanism housings 2 are installed so as to cross each other, and the self-propelled imaging device 10 according to the embodiment of the present invention is placed thereon. A cable 23 is connected to the self-propelled imaging device 10, and a video camera 14 is mounted on the cable 23.

  A visual inspection unit 20 is installed at a position (remote location) away from the reactor pressure vessel 1, and a controller 21 and a monitor 22 are provided there. A cable 23 is connected from the controller 21 to the self-propelled imaging device 10, whereby the self-propelled imaging device 10 is controlled from the controller 21 via the cable 23 and from the self-propelled imaging device 10. An image is transmitted to the controller 21.

  Therefore, the image captured by the video camera 14 mounted on the self-propelled imaging device 10 is displayed on the monitor 22, thereby monitoring the image by the operator (inspector) P and the self-propelled imaging device 10. Can be obtained. Note that, instead of the cable 23 at this time, wireless transmission means may be used to transmit / receive wireless operation signals and video signals.

  At this time, the operator P observes the image projected on the monitor 28 until the position where the video of the inspected part can be imaged by the video camera of the self-propelled imaging device 10 is between the control rod drive mechanism housing 2. The self-propelled imaging device 10 is self-propelled so as to sew, and the image of the region to be inspected displayed on the monitor 28 is observed to check and inspect the region to be inspected.

  Next, a self-propelled imaging device 10 according to an embodiment of the present invention will be described. As shown in FIG. 3 and FIG. Driving side wheels 12A and 12B and auxiliary side wheels 13 having no driving capability are provided so as to be capable of self-running, and a camera having an imaging capability, that is, a video camera 14 is mounted thereon.

  At this time, the video camera 14 is placed on a pedestal having a pan function and a tilt function by remote operation, that is, a so-called automatic pan head, so that the controller 21 can remotely control the imaging direction in any direction left, right, up and down. It has become.

  The main body frame 11 further includes drive sources 15A and 15B, power transmission mechanisms 16A and 16B, a balance weight 17, two front-to-back anti-falling members 18A and 18B, and two left-right pairs. The individual lateral fall prevention members 19A and 19B are provided. 3 and 4, the left is the front of the self-propelled imaging device 10 and the right is the rear.

  First, the drive sources 15A and 15B are constituted by electric motors, and rotate the left and right drive side wheels 12A and 12B independently through the power transmission mechanisms 16A and 16B. Electric power for this purpose is supplied from the controller 21 via the cable 23. In the case of a wireless system using wireless transmission means instead of the cable 23, it is necessary to separately mount a power supply device such as a battery.

  Next, although not shown, the auxiliary-side wheel 13 is supported so as to be rotatable with respect to the main body frame 11 by a vertical axis, and an offset is provided between the position of the vertical axis and the position of the axle at this time. Therefore, a function as a so-called caster is provided.

  Therefore, by independently controlling the rotation speed (rotation speed) and rotation direction of the driving wheels 12A and 12B, the controller 21 can freely move forward, backward, diagonally, curve, etc., including turning while stopped. Remote control is possible.

  At this time, the drive side wheels 12A and 12B and the auxiliary side wheel 13 are attached to the main body frame 11 so as to be positioned substantially at the apexes of the triangle, as is apparent from FIG. The surface is supported at three points, so that the lift of the wheel is suppressed even on a considerably uneven surface, and good road surface grounding is provided.

  Next, the balance weight 17 functions to adjust the axial load balance between the driving side wheels 12A and 12B and the auxiliary side wheel 13, and the driving side wheels 12A and 12B are directly below the center of gravity of the self-propelled imaging device 10. The weight and position are set so that the 12B two-wheel axle is located.

  Furthermore, the forward toppling prevention members 18A and 18B and the lateral toppling prevention members 19A and 19B are composed of members having an appropriate elastic force, such as a coil spring, for example. The three-point support with the running surface by the auxiliary side wheel 13 is projected from the lower surface of the main body frame 11 with a length that does not have a great influence during normal running, and its function will be described later.

  Next, the operation of the self-propelled imaging device 10 will be described. As described above, the rotational speeds of the left and right drive wheels 12A and 12B can be independently controlled by the controller 21, as described above. Therefore, for example, as shown in FIG. 2, if it is placed on the heat insulating material 3 in the lower mirror portion of the reactor pressure vessel 1, it can freely move forward and backward and turn on the floor surface of the heat insulating material 3. The video camera 14 can be moved to an arbitrary position by sewing between the control rod drive mechanism housings 2 and imaging can be performed.

  At this time, since the self-propelled imaging device 10 has the auxiliary wheel 13 as one wheel, the main body frame 11 can be slimmed and can be turned at that position while stopping, so-called small turning is effective, As a result, less space is required for turning, and the narrow portion can be easily approached.

  Therefore, according to the self-propelled imaging device 10, an image of the inspection target part required by the operator P is arbitrarily selected on the monitor 22 of the visual inspection unit 20 located away from the reactor pressure vessel 1. Visual inspection at a place where it is difficult to approach environmentally and spatially, such as the lower part of the reactor pressure vessel, can be easily performed.

  Next, as shown in FIGS. 5 and 6, the self-propelled imaging device 10 travels on the traveling surface 30 on which the obstacle S exists, and the drive-side wheels 12 </ b> A and 12 </ b> B and the auxiliary-side wheel 13 are connected. It is assumed that each touches the obstacle S. At this time, due to the axial load balance of the drive side wheels 12A and 12B and the auxiliary side wheel 13, in the case of FIG. 5, the obstacle S is overcome by the propulsive force due to the rotation of the drive side wheels 12A and 12B, and in the case of FIG. The auxiliary wheel 13 can be moved by the propulsive force in the traveling direction due to the rotation of the side wheels 12A and 12B and the slight upward force generated by the resultant force of the rotation of the auxiliary wheel 13 itself, and the obstacle 20 can be overcome. .

  Further, as shown in FIG. 7, when traveling on an undulating traveling surface 31, the possibility of a fall due to a forward leaning posture is increased due to the axial load balance between the drive side wheels 12 </ b> A and 12 </ b> B and the auxiliary side wheel 13. However, at this time, the forward toppling prevention member 18A (18B) 4 and the lateral toppling prevention member 19A (19B) come into contact with the running surface 31, and the fall can be suppressed.

  Therefore, according to the self-propelled imaging device 10, the video camera 14 can be moved without fear of falling even by the three-wheel traveling mechanism including the driving wheels 12A and 12B and the auxiliary wheels 13. As a result, The structure of the main body is simplified, so that the maintainability can be improved and the weight can be reduced.

  As a result, since the ground contact pressure by the wheel is suppressed, even if the running surface 30 having the obstacle S or the running surface 31 with undulations is poor in rigidity, there is no risk of damaging them, and remote visual inspection can be easily performed. Inspection can be possible.

  Next, a method for confirming the position of the self-propelled imaging device 10 according to the embodiment of the present invention will be described. In this case, the position of the self-propelled imaging device 10 can be determined from the surrounding scenery of the self-propelled imaging device 10 captured by the video camera 14 and projected on the monitor 22, but FIG. In this embodiment, the marker 40 is arranged in advance at a required position on the running surface 30 as a visible mark.

  In the case of the embodiment of FIG. 8, the operator P confirms that the marker 40 has been projected on the monitor 22, and has reached the position where the marker 40 has been placed in advance by the self-propelled imaging device 10. Therefore, the current position of the self-propelled imaging device 10 can be confirmed more accurately, and the self-propelled imaging device 10 can be accurately guided to the site to be examined in a short time.

  At this time, when the marker 40 is installed at a place where it is difficult to approach, the marker 40 is regularly attached to a band-shaped object, for example, the band steel 41, and the rigidity of the band steel 41 as shown in FIG. The steel strip 41 is inserted from the periphery of a place where access is difficult, for example, from the periphery of the heat insulating material 3, and is extended so as to be pushed to a place where access is difficult, so that it is installed at a required position. .

  In this case, it is possible to perform the operation while confirming the position of the self-propelled imaging device 10 by arranging a plurality of the steel strips 41 regularly and installing the markers 40 at all positions where it is difficult to approach. Therefore, for example, the self-propelled imaging device 10 can be accurately guided in a short time also to a part to be inspected such as the control rod drive mechanism housing 2 described above.

  Next, FIG. 10 uses an IC chip 42 in which traveling position information is recorded as a marker for position confirmation, and the self-propelled imaging device 10 is provided with a reading device 43 in accordance therewith. Here, an IC chip such as an RFID can be used as the IC chip 42. This RFID is a “Radio Frequency ID”, which has a function of responding to access by radio waves, and is not limited to location information, but also information according to user requests such as product or part information. Can also be stored.

  At this time, the reading device 43 has a function for reading the IC chip, and has a function for reading the IC chip by accessing the IC chip 42 by radio waves and reading the running position information recorded therein. At the same time, the travel route 35 traveled by the self-propelled imaging device 10 is stored as information, and a calculation function for controlling the operation of the self-propelled imaging device 10 is provided. However, the drive system control function of the self-propelled imaging device 10 by the reading device 43 may be provided in the controller 21 of the visual inspection unit 20 in a remote place.

  Therefore, as shown in FIG. 11, the IC chip 42 is installed at a point where the self-propelled imaging device 10 can travel between structures that obstruct travel, such as the control rod drive mechanism housing 2. . Then, when the self-propelled imaging device 10 is self-propelled on the heat insulating material 3, the reading device 43 reads the position information from the IC chip 42, and the read information and the history of the traveling route 35 of the self-propelled imaging device 10. From the information, the drive system of the self-propelled imaging device 10 is controlled so that the self-propelled imaging device 10 goes to the coordinates of the target inspection position.

  At this time, the return travel route from the target inspection position coordinates of the self-propelled imaging device 10 can also be set based on the history information of the travel route 35 stored in the reading device 43, so that it goes to the target inspection position coordinates. It is also possible to control to automatically return according to the return travel route that travels in the opposite direction.

  As in this embodiment, when the IC chip 42 is used as a marker indicating the position, an active IC chip having a transmission function can be used. Since the relative positional relationship between the device 43 itself and the IC chip 42 can be obtained as a kind of information for controlling the drive system, the guidance of the self-propelled imaging device 10 according to the travel route 35 described above is more accurate. It can be done well.

  Therefore, according to this embodiment, regarding the movement of the self-propelled imaging device 10 to the target inspection position coordinates, the guidance of the self-propelled imaging device 10 according to the traveling route 35 is automatically performed with high accuracy. As a result, according to this embodiment, the automatic traveling of the self-propelled imaging device 10 can be performed in a visual inspection at a place where environmental and spatial access is difficult such as the lower part of the reactor pressure vessel. Therefore, it can be carried out easily and in a short time.

  Next, FIG. 12 shows another embodiment of the self-propelled imaging apparatus 10, which is a caterpillar drive system using a sprocket 37 and a crawler belt 38 for driving the driving wheels 12 A and 12 B in the embodiment of FIG. The other configurations remain the same. At this time, needless to say, the power transmission mechanisms 16A and 16B are configured to transmit power to the sprocket 37.

  According to the embodiment of FIG. 12, the weight reduction and the simplification of the structure are realized as compared with the method in which the entire wheel used in the prior art is driven by the caterpillar, and the mobility in the narrow portion is achieved. It is possible to get over even high obstacles while securing the vehicle, and it is possible to obtain a traveling movement with better mobility.

It is explanatory drawing which shows 1st Embodiment of the remote visual inspection method by this invention. It is operation | movement explanatory drawing of 1st Embodiment of the remote visual inspection method by this invention. 1 is a side view showing a first embodiment of a self-propelled imaging device according to the present invention. It is a bottom view which shows 1st Embodiment of the self-propelled imaging device by this invention. It is explanatory drawing of the obstacle running operation | movement by 1st Embodiment of the self-propelled imaging device by this invention. It is explanatory drawing of the obstacle running operation | movement by 1st Embodiment of the self-propelled imaging device by this invention. It is explanatory drawing of the ramp running operation | movement by 1st Embodiment of the self-propelled imaging device by this invention. It is a side view which shows 2nd Embodiment of the self-propelled imaging device by this invention. It is explanatory drawing of driving | running | working operation | movement by 2nd Embodiment of the self-propelled imaging device by this invention. It is a side view which shows 3rd Embodiment of the self-propelled imaging device by this invention. It is explanatory drawing of driving | running | working operation | movement by 3rd Embodiment of the remote visual inspection method by this invention. It is a side view which shows 4th Embodiment of the self-propelled imaging device by this invention.

Explanation of symbols

1: Reactor pressure vessel 2: Housing for control rod drive mechanism 3: Thermal insulation (reactor pressure vessel lower thermal insulation)
10: Self-propelled imaging device (main unit)
11: Body frame 12A, 12B: Drive side wheel 13: Auxiliary side wheel 14: Video camera 15A, 15B: Drive source 16A, 16B: Power transmission mechanism 17: Balance weight 17
18A, 18B: Forward fall prevention member 19A, 19B: Lateral fall prevention member 20: Visual inspection part (remote location)
21: Controller 22: Monitor 23: Cable 30: Traveling surface 31: Riding traveling surface 35: Traveling route 37: Sprocket 38: Crawler belt (endless track)
40: Marker
41: Band steel 42: IC chip 43: Reading device P: Operator (inspector)
S: Obstacle

Claims (4)

The video camera mounted on the moving means captures images of the inspected target sites at a plurality of locations, and the image captured by the video camera is monitored at a remote location to visually inspect the target target sites at the plurality of locations. In the remote visual inspection method to be performed,
As the moving means, a self-propelled means having two wheels on the driving side and one wheel on the auxiliary side is used.
By monitoring the image taken by the video camera mounted on the self-propelled means at the remote place,
At least one of confirmation of the inspected part, position control of the self-propelled means and control of the imaging direction of the video camera and visual inspection of the inspected part can be obtained in the remote place. Remote visual inspection method. The remote visual inspection method according to claim 1,
Using a marker placed in the vicinity of the site to be examined,
The remote visual inspection method according to claim 1, wherein the position confirmation of the self-propelled means is given from a monitor of an image obtained by imaging the marker. The remote visual inspection method according to claim 1,
Using an IC chip placed in the vicinity of the site to be inspected,
The remote visual inspection method according to claim 1, wherein the position confirmation of the self-propelled means is given by radio wave access to the IC chip. A main body frame in which two driving wheels and one auxiliary wheel are arranged in a substantially triangular shape;
A balance weight provided on the main body frame so that the axle position of the two driving wheels is located directly below the overall center of gravity;
A forward turnover attached to the lower side of the main body frame so as to be positioned on one side and the other side in a direction substantially parallel to the axle on one side in a direction perpendicular to the axle of the two driving wheels. A prevention member;
Left-right fall mounted on the lower side of the main body frame so as to be positioned on one side and the other side in a direction substantially parallel to the axle on the other side in a direction perpendicular to the axle of the two driving wheels A prevention member;
Remote control means for independently controlling the rotational direction and the rotational speed of the two driving wheels,
A self-propelled imaging apparatus, wherein a video camera having a pan function and a tilt function by remote control is mounted on the main body frame.

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