KR20160037266A

KR20160037266A - Method for checking crack of cargo and appratus for the same

Info

Publication number: KR20160037266A
Application number: KR1020140128862A
Authority: KR
Inventors: 전상언
Original assignee: 삼성중공업 주식회사
Priority date: 2014-09-26
Filing date: 2014-09-26
Publication date: 2016-04-06

Abstract

A method for inspecting a cargo hold crack and a crack inspection apparatus therefor are disclosed. A method for inspecting a crack in a cargo hold according to an embodiment of the present invention includes the steps of: (a) spraying a cooling fluid onto an inner wall of a cargo hold using a spray device provided in a cargo hold to pre-cool the cargo hold before injecting liquefied gas into the cargo hold; And (b) detecting a part of the cargo hold inner wall showing a different temperature from the surrounding area due to a crack, using a camera attached to the robot.

Description

FIELD OF THE INVENTION [0001] The present invention relates to a method for inspecting a crack in a cargo hold,

The present invention relates to a method for inspecting a cargo hold crack and a crack inspection apparatus therefor.

The cargo hold of a ship is made of a material that can withstand cryogenic temperatures because it stores liquefied natural gas (LNG) cooled to about -163 ° C. It has an insulation structure that is resistant to thermal stress and heat shrinkage and can block heat intrusion. To this end, the cargo hold has a primary barrier, an upper insulation board, a secondary barrier and a lower insulation board and is provided in combination with an inner hull.

In the ceiling of the cargo hold, there is installed a liquefying water reservoir for unloading liquefied natural gas, and a gas discharge passage for discharging evaporative gas of the liquefied natural gas stored in the cargo hold. Various piping and the like for discharging evaporative gas of the liquefied natural gas stored in the cargo hold are complicatedly installed in the gas discharge passage.

The cargo hold is provided with a pump tower for loading and unloading liquefied natural gas. The pump tower is connected to the loading device and includes a filling pipe for introducing the liquefied natural gas into the cargo hold, a discharge pipe connected to the unloading device for discharging the liquefied natural gas inside the cargo hold, And emergency pipe used. The pipe of this pump tower is provided in the form of a truss-structured pipe structure. The pump tower is typically installed close to the bulkhead of the aft side and is supported by a base support provided on the bottom of the cargo hold in a fixed state on a liquid dome.

On the other hand, the space existing between the primary barrier and the secondary barrier of the cargo hold is filled with nitrogen gas. This is so that a constant pressure difference is maintained between the pressure inside the cargo hold and the pressure in the corresponding space filled with the nitrogen gas. For example, when the pressure inside the cargo hold filled with liquefied natural gas is in the range of 100 to 250 mbar, the pressure of the nitrogen gas filled in the space between the primary barrier and the secondary barrier is in the range of 5 to 10 mbar G Lt; / RTI > At this time, it is possible to determine whether the nitrogen gas and the liquefied natural gas leak or not by comparing the pressure difference with the internal set value.

In this regard, Korean Patent Laid-Open No. 10-2010-0088437 (hereinafter referred to as "Prior Art") discloses a method of injecting nitrogen gas into a primary heat insulating zone of a cargo hold, Discloses a technology for detecting the occurrence of a crack in a cargo area by sensing a change in the surface temperature of the film from a long distance. At this time, the nitrogen gas of the related art performs a function of preventing the vaporization of the supplied liquefied LNG to some extent by pre-cooling the temperature inside the cargo hold.

However, in the case of the prior art, after the temperature of the cargo window is cooled to a certain degree using nitrogen gas, a person must directly lift the camera equipment and find a site where cracks exist. At this time, it is very difficult to find the portion where fine cracks are generated by using nitrogen gas which is different from the actual temperature of the LNG filled in the cargo hold. If the actual LNG is filled in the cargo hold without finding any fine cracks, the area where the cracks are present may be enlarged and lead to a post LNG leak accident. It is also very difficult to check the presence of cracks due to liquefied natural gas at extremely low temperatures in the state where the liquefied natural gas is filled in the cargo hold.

Korean Patent Publication No. 10-2010-0088437 (Aug., 2010)

An embodiment of the present invention is to provide a method for inspecting a crack in a cargo hold by spraying a cooling fluid on the inner wall of a cargo hold to effectively check whether there is a minute crack present in the cargo hold, and a crack inspection apparatus therefor.

Further, even in the state where the liquefied natural gas is filled in the storage space in advance, the presence or absence of cracks can be effectively inspected using the robot.

According to an aspect of the present invention, there is provided a method of manufacturing a cargo hold, comprising the steps of: (a) pre-cooling a cooling fluid by spraying a cooling fluid on the cargo hold inner wall using a spray device provided in the cargo hold before injecting liquefied gas into the cargo hold; And (b) detecting a portion of the cargo hold inner wall showing a different temperature due to a crack, using a camera attached to the robot.

In the step (a), a cooling fluid is supplied through a pipe from a cooling fluid supply source, and the supplied cooling fluid is injected from the ceiling portion of the cargo hold into the cargo hold inner wall through a nozzle portion provided at one end of the pipe .

The cooling fluid may comprise a liquefied gas.

According to another aspect of the present invention, there is provided a method of producing a liquefied natural gas, comprising the steps of: (a) injecting liquefied gas into a cargo hold; And (b) detecting a portion where the bubble is generated due to a crack at the inner wall of the cargo hold by using a camera attached to the robot.

Wherein the step (b) includes the steps of: performing a crack inspection operation on an area having a large degree of the sloshing impact, based on area information of the cargo window previously divided according to a degree of sloshing impact; , And performing a crack inspection operation on the basis of the history information on the result of the previous crack inspection on the inner wall of the cargo hold with respect to the portion where the crack was previously present .

The method of claim 1, wherein, in the step (b), when a crack is present on the inner wall of the cargo hold, the crack is divided into a plurality of block regions and photographing information of a region where the detected crack exists, And extracting a block region of the existing portion.

According to another aspect of the present invention, there is provided a device for inspecting a crack in a cargo hold, the device comprising: a header installed inside the cargo hold to detect whether a crack exists in the cargo hold; A robot including a joint part in the form of a multi-joint which supports the part; And a control device for controlling the robot so that an inspection operation is performed on a site where a crack in the cargo hold inner wall is present based on at least one of a control command and an internal setting value received from the outside .

A spray pipe for supplying the cooling fluid from the cooling fluid supply source and a nozzle unit provided at one end of the spray pipe for spraying the cooling fluid to the inner wall of the cargo hold.

Wherein the nozzle unit comprises a plurality of frames formed in a number corresponding to the number of the pipes and communicating with the respective pipes constituting the spray pipe, the plurality of nozzle units being spaced apart from each other by a predetermined distance along the frame shape, And an injection nozzle arranged alternately in the arranged frame so that the cooling fluid is injected in a zigzag pattern.

Wherein the control device comprises: an area information storage part for storing area information divided according to a degree of sloshing impact in the cargo hold; and a history information storage part for storing information on a result of previous crack inspection on the inner wall of the cargo hold And controlling the robot to perform a crack inspection operation with priority given to an area where the sloshing impact is large, or by prioritizing a portion where cracks have previously existed based on the history information It is possible to control the robot to perform a crack inspection operation.

Wherein the robot further comprises a transceiver for transmitting photographing information of a portion of the cargo hold inner wall where the cracks are present to the control device, wherein the control device includes a map storing map information in which the cargo window is divided into a plurality of block regions And an extracting unit for extracting a block region of a portion where the crack exists based on the photographing information and the map information.

The method of inspecting a crack in a cargo hold according to an embodiment of the present invention and the crack inspection apparatus for the same can effectively inspect the presence of fine cracks existing in a cargo hold by spraying a cooling fluid on the inner wall of the cargo hold.

Further, even in a state in which the liquefied natural gas is filled in the storage space in advance, the presence or absence of cracks can be effectively inspected using the robot.

The effects of the present invention are not limited to the effects mentioned above, and other effects not mentioned can be clearly understood by those skilled in the art from the description of the claims.

1 is a cross-sectional view of a cargo hold equipped with a crack inspection apparatus according to an embodiment of the present invention.
2 is a block diagram of the crack inspection apparatus shown in FIG.
3 is a partial cutaway view showing a state in which the cargo hold shown in FIG. 1 is divided into a sloshing load area and a general area.
4 is a cross-sectional view of the cargo window shown in FIG.
FIG. 5 is a cross-sectional view showing the spray device shown in FIG. 2 installed in a cargo hold roof.
FIG. 6 is a perspective view showing a piping and a nozzle portion included in the spray device of FIG. 5; FIG.
FIG. 7 is a perspective view showing a state where a crack in the cargo hold is inspected in a state where the cargo window of FIG. 1 is filled with liquefied natural gas.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. The embodiments described below are provided by way of example so that those skilled in the art will be able to fully understand the spirit of the present invention. The present invention is not limited to the embodiments described below, but may be embodied in other forms. In order to clearly explain the present invention, parts not related to the description are omitted from the drawings, and the width, length, thickness, etc. of the components may be exaggerated for convenience. Like reference numerals designate like elements throughout the specification.

The liquefied gas may include LNG, LPG, L-CO2, and DME. Hereinafter, liquefied natural gas will be described as an example for convenience of explanation.

Referring to FIGS. 1 and 2, a crack inspection apparatus 200 according to an embodiment of the present invention checks whether a crack exists in an inner wall of a cargo hold 100 storing a cryogenic liquid such as liquefied natural gas . The structure of the cargo hold 100 disposed inside the hull 1 may include a primary barrier 3, a secondary barrier 5 and upper / lower insulation boards 7 and 8.

The cargo hold 100 includes an upper flat portion 111 (also referred to as a ceiling portion) covering the upper side of the storage space S, a lower flat portion 112 covering the lower side, both side wall portions 113 and 114 covering the side, Upper first inclined portions 115 and 116 connecting the planar portion 111 and the side wall portions 113 and 114 and lower second inclined portions 117 and 118 connecting the lower planar portion 112 and the side wall portions 113 and 114, . In FIG. 1, the barrier structure including the primary barrier 3, the secondary barrier 5 and the upper / lower heat insulating boards 7 and 8 has been simplified to facilitate understanding.

3, the cargo hold 100 may include a reinforced loaded area R and a normally loaded area N depending on the extent to which the sloshing impact is applied, . &Lt; / RTI > The sloshing load region R is a region in which a sloshing impact generated by the flow of the LNG carrier in the cargo hold 100 is greater than that applied to the general region N,

1 and 3, the sloshing load region R in the cargo hold 100 includes a portion where the second inclined portions 117 and 118 and the side wall portions 113 and 114 are connected to each other and a portion where the upper side flat portion 111 and the first And the inclined portions 115 and 116 may be connected to each other. The general region N is a region where the LNG load due to a relatively sloshing impact is smaller than the sloshing load region R and includes regions except for the sloshing load region R described above. The crack inspection apparatus 200 can perform the crack inspection with priority given to the sloshing load region R where the degree of sloshing impact is large.

As shown in FIG. 2, the crack inspection apparatus 200 includes a robot 210, a control device 220, and a spray device 230.

The robot 210 includes a header portion 211, a joint portion 212, and a transmission / reception portion 213. The robot 210 may be installed such that the joint part 212 supporting the header part 211 extends to the inside of the cargo hold 100. For example, 5) or an opening of a liquid dome (not shown) or the like. The portion through which the joint part 212 of the robot 210 passes may be sealed by a sealing means including a heat insulating material 201 or the like on the ceiling side of the cargo hold 100. [

The header portion 211 is installed inside the cargo hold 100 and houses a camera or the like for detecting the presence of a crack in the inner wall of the cargo hold 100. [ The camera can be protected by the header portion 211 so that it can be used even at a cryogenic temperature, and can include an infrared camera, a CC camera, and the like. The header portion 211 can be rotatably mounted on the joint portion 212 by a motor or the like.

The joint part 212 supports the header part 211 and includes a joint part 212 of a multi-joint type which is driven by a motor or the like. The joint part 212 may include a rotating joint supporting the header part 111 and rotating in the left and right direction and a translating joint connected to the rotating joint and linearly moving in the left or right direction or the up and down direction.

The transceiver 213 transmits photographing information or the like including an image of a part where a crack exists to an external device. The shooting information may include various information about the shooting image, the camera angle, the joint angle, and the like. The transmission / reception unit 213 may be provided in the header unit 211, and may transmit the photographing information to the control unit 220 through wired / wireless communication. When wired communication is performed, the communication line may be inserted through the inside of the joint part 212 to connect the transmission / reception unit 213 and the external device to each other.

The control device 220 may control the robot 210 to perform a crack inspection operation on the inner wall of the cargo hold 100. [ In addition, the control device 220 can transmit a control command to the spray device 230 to spray the cooling fluid to the inner wall of the cargo hold 100. [ The control device 220 may perform the control operation of the robot 210 based on at least one of the information and the internal setting value received from the outside. The control unit 220 may include a communication unit 221, a storage unit 225 and an extraction unit 226 and may be installed outside the cargo hold 100 to interlock with the robot 210.

The communication unit 221 can perform wired / wireless communication with, for example, the transceiver unit 213 and the spray device 230 described above. In addition, communication with various external devices can be performed.

The storage unit 225 stores information related to the crack inspection operation through the control of the robot 210. For example, control information, an algorithm, a program, and various setting values for controlling the robot 210 can be stored. The storage unit 225 may include an area information storage unit 222, a history information storage unit 223, and a map storage unit 224.

The area information storage unit 222 stores information on the above-described sloshing load area R (see FIG. 3) and the general area N (see FIG. 3). The controller 220 controls the robot 210 to perform a crack inspection operation on the basis of the information stored in the area information storage unit 222 with the sloshing load area R having a high degree of sloshing impact applied as a priority Can be controlled. This is because there is a high possibility that cracks exist in the sloshing load region R where the sloshing impact is large, and there is a high possibility that the fine cracks already existing are further enlarged by the sloshing impact.

The history information storage unit 223 stores information on the result of previous crack inspection on the inner wall of the cargo hold 100. [ The controller 220 can control the robot 210 to perform a crack inspection operation based on the information stored in the history information storage unit 223 with respect to the portion where the crack was previously present and the repair was performed. This is because, even if the repair is performed, there is a high possibility that cracks are generated again in the area where the cracks existed before.

The map storage unit 224 stores map information that divides the cargo hold 100 into a plurality of block areas. 4, the cargo hold 100 may be divided into a plurality of block areas B based on the design information of the cargo hold 100, and the map storage part 224 may store the cargo hold information as the cargo hold map information . This is because if the crack region 100a is included in the specific block region B1, the control unit 220 can easily detect a cracked portion and control the robot 210 to perform a more detailed inspection In order to be able to carry out. 4, the robot 210 is omitted for convenience of explanation.

The extracting unit 226 extracts a block region in a region where a crack exists based on the photographing information and map information photographed by the camera of the robot 210. [ The extracted block area may be stored in the storage unit 225 as a set value. That is, as shown in FIG. 4, if the extraction unit 226 extracts the block area B1 in which the crack 100a exists based on the photographing information and the map information for the part where the crack 100a exists The controller 220 controls the joint part 212 so that the header part 211 of the robot 210 approaches the block area B1 in which the crack 100a exists using the extracted information. At this time, the photographing information about the site where the crack 100a exists may include information about the image, the photographing angle, and the like of the relevant region. Based on the image analysis and photographing angle, (B1) can be extracted. As an image analysis method, for example, an edge extraction method may be used.

2, 5 and 6, the spray device 230 includes a spray pipe 240 for receiving a cooling fluid from a cooling fluid supply source 321, and a spray pipe 240 provided at one end of the spray pipe 240, And a nozzle portion 250 for spraying the cooling fluid to the inner wall.

The cargo hold 100 needs to cool the inner wall of the cargo hold 100 beforehand to prevent thermal shock before injecting the cryogenic liquid such as liquefied natural gas into the cargo hold 100. To this end, the stored cooling fluid may be injected into the inner wall of the hold 100. At this time, when there is a crack in the inner wall of the cargo hold 100, the corresponding crack is enlarged by the cooling fluid. This makes it easy to detect minute cracks through the crack inspection apparatus 200. The cooling fluid comprises liquefied natural gas.

The gas passage furnace structure 301 is provided at one side of the ceiling of the cargo hold 100 for discharging (evaporating) gas in the cargo hold 100 for storing the liquid. For example, the gas passage structure 301 may be installed at the center of the ceiling portion. However, the installation position of the gas passage furnace structure 301 is not limited to this, and may be provided at another portion of the ceiling portion.

The gas pipe furnace structure 301 includes a pipeline structure 310, a spray pipe 240, a nozzle unit 250, and a pressure control valve structure 260 installed outside the pipeline structure for controlling the pressure inside the cargo hold . The pressure control valve structure 260 is briefly labeled for simplicity of illustration. Here, the channel structure 310 is installed so as to pass through one side of the ceiling of the cargo hold 100, and discharges the gas inside the cargo hold 100 to the outside. The outer surface of the channel structure 310 may be provided with a heat insulating material 310a for heat insulation.

The spray pipe 240 extends from the outside of the pipeline structure 310 to the inside of the cargo hold 100 through the pipeline structure 310 and supplies the cooling fluid to the inside of the cargo hold 100. One or more spray pipes 240 may be provided, and two spray pipes 240 are provided in this embodiment. In addition, the spray pipe 240 may be partially bent so as to cope with heat shrinkage and thermal expansion due to cryogenic liquid contents. At one end of the spray pipe 240 extending to the inside of the cargo hold 100, a nozzle unit 250 for injecting a cooling fluid to the inner wall of the cargo hold 100 is installed.

The nozzle unit 250 injects the cooling fluid flowing along the spray pipe 240 into the inner wall of the cargo hold 100. The nozzle unit 250 may include a frame 253 and an injection nozzle 255.

The frame 253 is in communication with the pipes 240a and 240b constituting the spray pipe 240 extended to the inside of the cargo hold 100 and formed in a number corresponding to the number of the pipes 240a and 240b, . At this time, each frame 253 may be connected to each of the pipes 240a and 240b of the spray pipe 240 in a one-to-one correspondence manner. Such a frame 253 may be located on the ceiling of the cargo hold 100. In addition, the frame 253 may be formed in a shape corresponding to the shape of the ceiling of the cargo hold 100, and may be provided in a circular rim shape, for example. However, the present invention is not limited to this, and may be formed in various rim shapes such as a polygon including a rectangle. That is, if the ceiling of the hold 100 having the gas passage structure 301 is rectangular, it may be advantageous for efficient cooling to be formed by a frame 253 having a rectangular frame shape rather than a circular shape.

The injection nozzle 255 is a part for injecting a cooling fluid, and a plurality of the injection nozzles 255 may be provided in the periphery of the frame 253 at a certain distance along the shape of the frame 253. The cooling fluid flowing along the pipes 240a and 240b of the spray pipe 240 reaches the frame 253 and is injected to the inner wall of the cargo hold 100 through the injection nozzle 255. [ Each injection nozzle 255 may be formed in a zigzag shape toward the inside of the hold 100 so that the injection ranges do not overlap. To this end, jet nozzles 255 are alternately arranged in each frame 253 on which the layer is disposed, so that the cooling fluid is jetted in a zigzag pattern through the jet nozzles 255.

Hereinafter, a method for inspecting a cargo hold crack will be described based on the contents described in Figs. 1 to 6. Fig.

First, before the liquefied natural gas is injected into the cargo hold 100, the cooling fluid is sprayed on the inner wall of the cargo hold 100 using the spray device 230 provided in the cargo hold 100 to cool it in advance (step A1) . The cooling fluid is supplied from the cooling fluid supply source 231 through the pipe 240 and the cooling fluid is supplied from the ceiling portion side of the cargo hold 100 through the nozzle portion 250 provided at one end of the pipe 240, As shown in FIG. The cooling fluid may be liquefied natural gas. When fine cracks 100a (see FIG. 4) are present, their size can be enlarged by the cooling fluid.

Next, using a camera attached to the robot 210, a portion indicating a temperature different from that of the surrounding due to a crack in the inner wall of the cargo hold 100 is detected (step A2). In the above step A1, the temperature of the portion where the fine cracks 100a are present is enlarged by the cooling fluid as compared with the other portions.

Referring to FIG. 7, first, a liquefied natural gas (LNG) is injected into the cargo hold 100 to fill the cargo hold 100 (step B1). The liquefied natural gas (LNG) may be filled into the cargo hold 100 through a pump tower (not shown). In the state where the liquefied natural gas (LNG) is filled, the size of the portion where the crack of the cargo hold 100 exists is enlarged.

Next, using a camera attached to the robot 210, a portion where the bubble 9 is generated due to a crack at the inner wall of the cargo hold 100 is sensed (step B2). As described above, it is possible to detect a portion where cracks are effectively present even in the state where the liquefied natural gas is filled in the cargo hold 10.

In the above-described steps A2 and B2, a crack inspection operation may be performed with priority given to a region where the sloshing impact is large, or a crack inspection operation may be performed first on a region where a crack has previously occurred . Or a crack inspection operation may be performed according to an internal set value while approaching the side wall and the bottom surface from the cargo hold ceiling portion. This operation can be set differently depending on the shape and structure of the cargo hold.

In the above-described steps A2 and B2, when a site where a crack 100a exists due to an ambient temperature difference or a bubble is detected, photographing information including an image of the site may be transmitted to the control device 220 have. As shown in Fig. 4, the controller 220 extracts the block area B1 of the part where the crack 100a exists, based on the photographing information and the map information of the corresponding part, And controls the robot 210. The controller 220 moves the header portion 211 of the robot 210 to a distance close to the block region B1 under the control of the joint portion 212 and performs a close inspection on a portion where the crack 100a exists .

Each component shown in FIG. 2 may be composed of a 'module'. The term 'module' refers to a hardware component such as software or a field programmable gate array (FPGA) or application specific integrated circuit (ASIC), and the module performs certain roles. However, a module is not limited to software or hardware. A module may be configured to reside on an addressable storage medium and may be configured to execute one or more processors. The functionality provided by the components and modules may be combined into a smaller number of components and modules or further separated into additional components and modules.

The foregoing has shown and described specific embodiments. However, it is to be understood that the present invention is not limited to the above-described embodiment, and various changes and modifications may be made without departing from the scope of the technical idea of the present invention described in the following claims It will be possible.

1: Hull 100: Cargo hold
200: crack inspection device 210: robot
220: Control device 230: Spray device

Claims

(a) spraying a cooling fluid on the inner wall of the cargo hold using a spray device provided in the cargo hold to pre-cool the cargo hold before injecting the liquefied gas into the cargo hold; And
(b) using a camera attached to the robot to detect a portion of the cargo hold inner wall showing a different temperature from the surrounding due to a crack.

The method according to claim 1,
Wherein the step (a) includes the steps of: receiving a cooling fluid from a cooling fluid supply source through a pipe;
And injecting the supplied cooling fluid from the ceiling portion of the cargo hold to the inner wall of the cargo hold through a nozzle portion provided at one end of the pipe.

The method according to claim 1,
Wherein the cooling fluid comprises liquefied gas.

(a) injecting liquefied gas into the cargo hold to fill the cargo hold; And
(b) detecting a bubble generation site due to a crack at the inner wall of the cargo hold using a camera attached to the robot.

The method according to claim 1 or 4,
Wherein the step (b) includes the steps of: performing a crack inspection operation on an area having a large degree of the sloshing impact, based on area information of the cargo window previously divided according to a degree of sloshing impact; ,
And a crack inspection operation is performed on the basis of the history information on the result of the previous crack inspection on the inner wall of the cargo hold, Way.

The method according to claim 1 or 4,
The method of claim 1, wherein, in the step (b), when a crack is present on the inner wall of the cargo hold, the crack is divided into a plurality of block regions and photographing information of a region where the detected crack exists, Further comprising the step of extracting a block region of the existing portion.

A cargo hold crack inspection apparatus for performing a cargo hold crack inspection,
A robot installed inside the cargo hold, the robot including a header having a built-in camera for detecting presence or absence of a crack in the cargo hold inner wall, and a articulated joint for supporting the header; And
And a control device for controlling the robot so that an inspection operation is performed on a site where cracks in the cargo hold inner wall are present based on at least one of a control command and an internal set value received from the outside.

8. The method of claim 7,
Further comprising a spray pipe for receiving a cooling fluid from a cooling fluid supply source and a nozzle unit provided at one end of the spray pipe for spraying a cooling fluid to the inner wall of the cargo hold.

9. The method of claim 8,
Wherein the nozzle unit includes a frame which is formed in a multi-layered structure and communicates with the respective pipes constituting the spray pipe, the number of which corresponds to the number of the pipes,
And a plurality of jet nozzles arranged alternately spaced apart from each other by a predetermined distance along the frame shape so as to alternately jet the cooling fluid in a zigzag pattern.

8. The method of claim 7,
The control device includes an area information storage unit for storing the area information that is divided according to the degree of the sloshing impact in the cargo hold,
Further comprising at least one of a history information storage unit for storing information on a result of previous crack inspection of the inner wall of the cargo hold,
The robot may be controlled such that a crack inspection operation is performed with priority given to a region where the sloshing impact is large,
And controls the robot to perform a crack inspection operation based on the history information, with a position where a crack was previously present at a priority.

8. The method of claim 7,
Wherein the robot further comprises a transceiver for transmitting photographing information of a portion of the cargo hold inner wall where a crack is present to the control device,
The control device includes a map storage unit for storing map information that divides the cargo window into a plurality of block areas,
Further comprising an extracting unit for extracting a block region of a portion where the crack exists based on the shooting information and the map information.