Dock monitoring equipment, docking system and docking method for underwater docking structures

Abstract

This application provides a docking monitoring device, docking system, and docking method for underwater docking structures. The underwater docking structure includes a first annular component and a second annular component located underwater. The second annular component is deployed underwater using a hoisting and deployment device to dock and assemble with the first annular component, or is lifted upwards using the same device to separate from the first annular component. The first annular component forms a positioning element, and the second annular component forms a positioning mating element. Positioning is achieved through the positioning mating element and the positioning element. The device includes: multiple lifting mechanisms, each facing a positioning element; multiple image acquisition devices, each mounted on a lifting mechanism, each lifting mechanism configured to move the image acquisition device in the same direction as the second annular component to continuously acquire images containing the second annular component; and a display device for displaying the images acquired by the multiple image acquisition devices.

Description

Technical Field

[0001] This invention relates to the field of underwater docking technology, and in particular to a docking monitoring device, docking system and docking method for underwater docking structures. Background Technology

[0002] The pool-type heating reactor is an atmospheric pressure deep-water pool-type heating reactor. To ensure reactor safety and heating quality, the pool is approximately 26 meters deep. Due to design requirements, the reactor's overall components are divided into several sections, mainly including the core base, lower suspended platform, middle suspended platform, and upper suspended platform. These sections are connected by flange structures, with a total platform height of approximately 24 meters. There are no bolts or gaskets between the flanges of the upper and middle suspended platforms, or between the middle and lower suspended platforms; leakage is entirely controlled by the flanges' own sealing structure. The remote assembly and disassembly of the deep-water suspended platforms is one of the major challenges in reactor component installation and maintenance. Summary of the Invention

[0003] To address the aforementioned technical problems, embodiments of this application provide a docking monitoring device, docking system, and docking method for underwater docking structures.

[0004] In a first aspect, embodiments of this application provide a docking monitoring device for an underwater docking structure. The underwater docking structure includes a first annular component located underwater and a second annular component for docking and assembly with the first annular component. The second annular component is deployed underwater using a hoisting and launching device to dock with the first annular component, or is hoisted upwards using the same device to separate from the first annular component. The first annular component has multiple circumferentially distributed and vertically extending positioning elements, and the second annular component correspondingly has multiple circumferentially distributed and vertically extending positioning mating elements. The second annular component and the first annular component are positioned by insertion of the positioning mating elements and the positioning elements. The device includes: multiple lifting mechanisms arranged underwater around the first annular component, each lifting mechanism facing one positioning element; multiple image acquisition devices, each image acquisition device disposed on one of the lifting mechanisms, each lifting mechanism configured to drive the image acquisition device to move in the same direction as the second annular component during its underwater ascent or descent, to continuously acquire images containing the second annular component; and a display device for displaying the images acquired by the multiple image acquisition devices.

[0005] Secondly, embodiments of this application provide a docking system for an underwater docking structure. The underwater docking structure includes a first annular component located underwater and a second annular component for docking and assembly with the first annular component. The first annular component has a plurality of positioning elements distributed circumferentially and extending vertically. Correspondingly, the second annular component has a plurality of positioning mating elements distributed circumferentially and extending vertically. The second annular component and the first annular component are positioned by insertion of the positioning mating elements and positioning elements. The docking system includes: a hoisting and launching device for launching the second annular component underwater to dock and assemble the second annular component with the first annular component; or for hoisting the second annular component upward to separate the second annular component from the first annular component; and docking monitoring equipment as described in the first aspect of this application.

[0006] Thirdly, embodiments of this application provide a docking method for an underwater docking structure. The method is implemented using the system of the second aspect of this application and includes: step S1, obtaining a first reference for a first annular component and a second reference for a second annular component, and displaying them on a display device; step S2, calibrating multiple image acquisition devices; step S3, using a hoisting and launching device to launch the second annular component underwater or to hoist the second annular component upwards; step S4, controlling multiple image acquisition devices to continuously move in the same direction as the second annular component in the water and continuously acquire images containing the second annular component; step S5, processing the images to obtain the pose and angle of the second annular component; and step S6, adjusting the hoisting and launching device according to the first reference for the first annular component and the second reference for the second annular component displayed on the display device to change the pose and angle of the second annular component, so that the first reference displayed on the display device is aligned with the second reference.

[0007] Using the docking monitoring device of this application embodiment, the user can observe the position and tilt angle of the second annular component in real time during the docking or disassembly of the second annular component with the first annular component underwater, based on the image displayed on the display device. This allows the user to use the hoisting and deployment device to adjust the position and tilt angle of the second annular component to a preset position and preset angle, thereby facilitating smooth assembly or disassembly. Attached Figure Description

[0008] Other objects and advantages of the invention will become apparent from the following description of the invention with reference to the accompanying drawings, and will help to provide a comprehensive understanding of the invention.

[0009] Figure 1 This is a schematic diagram of the docking system according to an embodiment of the present invention;

[0010] Figure 2 This is a schematic diagram of a docking monitoring device according to an embodiment of the present invention;

[0011] Figure 3 This is a schematic top view of a docking monitoring device according to an embodiment of the present invention;

[0012] Figure 4 The image displayed on the screen shows the images captured by each image acquisition device.

[0013] Figure 5 This is a schematic diagram of the lifting mechanism and radial moving mechanism according to an embodiment of the present invention;

[0014] Figure 6 yes Figure 5 The diagram shows the structure of the traction device.

[0015] Figure 7 yes Figure 5 The diagram shows the structure of the lifting platform.

[0016] Figure 8 yes Figure 5 The diagram shows the structure of the radial movement mechanism.

[0017] Figure 9 This is a schematic diagram of the structure of a gimbal camera according to an embodiment of the present invention;

[0018] Figure 10 This is a schematic diagram of the supplementary lighting range of the supplementary lighting source and the camera field of view according to an embodiment of the present invention;

[0019] Figure 11 This is a schematic diagram of the structure of a light source according to an embodiment of the present invention;

[0020] Figure 12 This is a schematic diagram of the structure of a three-dimensional calibration plate according to an embodiment of the present invention;

[0021] Figure 13 It is the control field data obtained by using a single camera to acquire a stereo calibration plate.

[0022] It should be noted that the accompanying drawings are not necessarily drawn to scale, but are shown only in a schematic manner without affecting the reader's understanding.

[0023] Explanation of reference numerals in the attached figures:

[0024] 10. Water tank; 11. First annular component; 111. Positioning component; 12. Second annular component; 121. Positioning mating component; 13. Lifting and launching device;

[0025] 20. Image acquisition device;

[0026] 30. Supplemental light source; 31. Inner ring LED group; 310. Inner ring LED; 321. First outer ring LED group; 3210. First outer ring LED; 322. Second outer ring LED group; 3220. Second outer ring LED;

[0027] 40. Radial moving mechanism; 41. Slide rail; 42. Load-bearing roller; 43. Support shaft; 44. Sliding element;

[0028] 51. Processor; 52. Display device;

[0029] 60. 3D calibration plate; 61. Calibration surface; 610. Marker frame; 611. Marker point;

[0030] 70. Lifting mechanism; 71. Base; 72. Guide rod; 73. Lifting platform; 731. Frame; 732. Guide wheel; 74. Traction device; 741. Motor mounting component; 742. Motor; 743. Bearing housing; 744. Winding roller; 745. Pressing roller; 746. Tensioning wheel; 75. Traction rope;

[0031] 80. Gimbal camera; 81. Base; 82. Rotary hinge; 83. First lens barrel; 84. Second lens barrel. Detailed Implementation

[0032] To make the objectives, technical solutions, and advantages of this invention clearer, the technical solutions of this invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of this invention. Obviously, the described embodiments are one embodiment of this invention, and not all embodiments. Based on the described embodiments of this invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this invention.

[0033] It should be noted that, unless otherwise defined, the technical or scientific terms used in this application shall have the ordinary meaning as understood by one of ordinary skill in the art to which this invention pertains.

[0034] In the description of the embodiments of the present invention, "multiple" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0035] This invention provides a docking monitoring device for underwater docking structures.

[0036] See Figure 1 and Figure 2The underwater docking structure includes a first annular component 11 located underwater and a second annular component 12 for docking and assembly with the first annular component 11. The second annular component 12 is deployed underwater using a lifting and launching device 13 to dock and assemble with the first annular component 11, or is lifted upwards using the lifting and launching device 13 to disassemble from the first annular component 11. The first annular component 11 has a plurality of circumferentially distributed and vertically extending positioning members 111, and the second annular component 12 correspondingly has a plurality of circumferentially distributed and vertically extending positioning mating members 121. The second annular component 12 and the first annular component 11 are positioned by insertion of the positioning mating members 121 and the positioning members 111.

[0037] In some embodiments, the first annular component 11 can be the base of the reactor, and the second annular component 12 can be the reactor basket. In the illustrated embodiment, the positioning element 111 is a positioning pin, and correspondingly, the positioning mating element 121 is a positioning groove.

[0038] The docking monitoring device of this application embodiment includes: multiple lifting mechanisms 70, multiple image acquisition devices 20, and a display device 52. The multiple lifting mechanisms 70 are arranged underwater around a first annular component 11, with each lifting mechanism 70 facing a positioning component 111. Each image acquisition device 20 is disposed on one lifting mechanism 70, and each lifting mechanism 70 is configured to drive the image acquisition device 20 to move in the same direction as the second annular component 12 during its underwater ascent or descent, so as to continuously acquire images containing the second annular component 12. The display device 52 is used to display the images acquired by the multiple image acquisition devices 20. Using the docking monitoring device of this application embodiment, the user can observe the position and tilt angle of the second annular component 12 in real time during the underwater docking or disassembly process of the second annular component 12 with the first annular component 11, based on the images displayed on the display device 52. This allows the user to use the hoisting and deployment device 13 to adjust the position and tilt angle of the second annular component 12 to a preset position and angle, thereby facilitating smooth assembly or disassembly.

[0039] See Figure 3 The first annular component 11 has four positioning elements 111 evenly spaced along the circumference, and the second annular component 12 correspondingly has four positioning mating elements 121 evenly spaced along the circumference. The docking monitoring equipment includes four lifting mechanisms 70 and four image acquisition devices 20. The four lifting mechanisms 70 are evenly spaced along the circumference inside the water tank 10.

[0040] Figure 4 The image displayed on the display device 52 shows the images captured by each image acquisition device 20. Figure 4 In the process, the second annular component 12 descends underwater to a position where it docks with the first annular component 11. Figure 4Area A in the image displays images of the four docking positions. Based on this image, the user can observe the relative positions between the positioning component 111 and the positioning mating component 121 in real time, so as to adjust the position and tilt angle of the second annular component 12 using the hoisting and delivery device 13, so that the second annular component 12 can be smoothly docked with the first annular component 11. Figure 4 Area B in the diagram shows that the display device 52 is also equipped with camera control buttons, allowing the user to adjust the angle or magnification of the corresponding camera according to the image at the docking position, so that the user can observe the image at the docking position more clearly.

[0041] See Figure 5 The lifting mechanism 70 may include: a base 71, multiple guide rods 72, a lifting platform 73, a traction device 74, and a traction rope 75. Each guide rod 72 extends vertically upward from the base 71, and the lifting platform 73 is slidably mounted on the guide rod 72. The traction device 74 is mounted on the top of the guide rod 72. One end of the traction rope 75 is connected to the lifting platform 73, and the other end is pulled by the traction device 74, so that the lifting platform 73 can slide along the guide rod 72 through the traction device 74 and the traction rope 75. The lifting mechanism 70 is mainly constructed of aluminum profiles.

[0042] See Figure 6 The traction device 74 includes a motor 742, a motor mounting bracket 741, a bearing housing 743, a winding drum 744, a pressing roller 745, and a tensioning roller 746. The tops of each guide rod 72 are connected to a top plate. The motor 742 is mounted on the top plate via the motor mounting bracket 741. The winding drum 744 is mounted on the top plate via the bearing housing 743. The traction rope 75 is wound around the winding drum 744. The motor 742 releases or tightens the traction rope 75 by driving the winding drum 744 to rotate in both directions. The tensioning roller 746 is used to tension the traction rope 75. The pressing roller 745 is arranged parallel to the winding drum 744, and the two abut against each other to press the traction rope 75 tightly and prevent it from shifting.

[0043] In some embodiments, motor 742 can be a rotary motor. A 360° rotation angle can be achieved by remotely controlling the rotation of the rotary motor. The gear at the lower part of the rotary motor forms a planetary gear structure relative to the main shaft gear, allowing the gear, the connected rotary motor, and the support to rotate along the main shaft. The rotation angle can be determined by data observed by the visualization system, and the angle change can be adjusted through the control system of the rotary motor to position the camera at the optimal monitoring position.

[0044] See Figure 7The lifting platform 73 includes a frame 731 and guide wheels 732. The image acquisition device 20 is mounted on the frame 731. A traction rope 75 is mounted on the frame 731, and the guide wheels 732 are mounted on both sides of the frame 731 for engaging with guide rods 72. In the illustrated embodiment, there are four guide rods 72. Every two guide rods 72 are located on one side of the frame 731. Correspondingly, the lifting platform 73 includes eight guide wheels 732. Every four guide wheels 732 form the four corners of a rectangle on one side of the frame 731. These four guide wheels 732 slide in engagement with two guide rods 72 on the corresponding side. In this embodiment, since the image acquired by the image acquisition device 20 is needed to achieve precise alignment between the first annular component 11 and the second annular component 12, the image acquisition device 20 requires high stability. The lifting platform 73 in this embodiment is configured as described above to ensure that the image acquisition device 20 can rise and fall smoothly.

[0045] The docking monitoring equipment also includes a radial movement mechanism 40, used to carry the lifting mechanism 70 radially along the first annular component 11. By setting the radial movement mechanism 40, the radial position of the image acquisition device 20 can be adjusted to acquire the desired image.

[0046] See Figure 8 The radial moving mechanism 40 includes two radially extending slide rails 41 and a sliding member 44 slidably disposed on the two slide rails 41. The lifting mechanism 70 is disposed on the sliding member 44. The sliding member 44 is connected to the slide rails 41 through a load-bearing roller 42 and a support shaft 43, which helps to ensure that the sliding member 44 does not disengage from the slide rails 41 when sliding radially.

[0047] In some embodiments, the docking monitoring device further includes a processor 51, configured to process an image containing the first annular component 11 and an image containing the second annular component 12, to obtain a first reference for the first annular component 11 and a second reference for the second annular component 12, and display them on a display device 52, so that the user can align the first annular component 11 and the second annular component 12 according to the image displayed on the display device 52. The first reference and the second reference may, for example, be the axes of the first annular component 11 and the second annular component, respectively. Alternatively, the first reference may be the axis of the first annular component 11 and the center line of each positioning mating member 121; the second reference may be the axis of the second annular component 12 and the center line of each positioning member 111.

[0048] The docking monitoring equipment may also include a synchronization controller and a host computer. The synchronization controller is electrically connected to each image acquisition device 20 and is connected to the host computer to control all image acquisition devices 20 to acquire data simultaneously.

[0049] Underwater installation environments are complex and require high precision. Due to water depth, the light intensity cannot guarantee that the imaging will meet design requirements. To compensate for insufficient light, in some embodiments, the docking monitoring equipment also includes multiple supplementary lighting sources 30, each used to supplement the lighting of a corresponding image acquisition device 20.

[0050] The image acquisition device 20 can be a camera. The camera can be a high-definition camera. Due to the complex and changeable underwater environment, fixed focus cannot meet the requirements. Therefore, the camera must be a zoom camera with a resolution of 12 million pixels and be remotely controllable via software.

[0051] In some embodiments, the docking monitoring equipment further includes: multiple pan-tilt units, each pan-tilt unit being used to mount an image acquisition device 20 and a supplementary light source 30.

[0052] See Figure 9 The gimbal includes a base 81, a pivot 82, a first lens barrel 83, and a second lens barrel 84. The base 81 is mounted on the lifting platform 73 of the lifting mechanism 70. The pivot 82 is mounted on the base 81 and can rotate relative to the base 81 along a vertical axis. The first lens barrel 83 and the second lens barrel 84 are respectively mounted on opposite lateral sides of the pivot 82, and can rotate independently relative to the pivot 82 along a pitch axis. An image acquisition device 20 and a supplementary light source 30 are respectively mounted inside the first lens barrel 83 and the second lens barrel 84. In this embodiment, the gimbal, the supplementary light source 30, and the image acquisition device 20 together form a gimbal camera 80. The gimbal camera 80 adopts a dual-ear design, where the ear functions as supplementary light and imaging, ensuring image quality.

[0053] The gimbal's outer shell is mainly made of 304 stainless steel, which has strong corrosion resistance and reliability, enabling the entire device to work underwater for extended periods of time.

[0054] To ensure 360° monitoring without blind spots, the device employs a dual-rotation working mode along the X and Y axes. The space is divided into four sections using these axes, enabling comprehensive monitoring in both horizontal and vertical directions. The pan-tilt unit also utilizes a modular design for its internal functional components, ensuring that each part operates independently without interference.

[0055] Figure 10 A schematic diagram showing the supplementary lighting range α1 of the supplementary lighting source 30 and the camera field of view α2 is shown. See also Figure 10Based on the nearest and farthest working distances of the image acquisition device 20, a certain angle β exists between the central axis of the supplementary light source 30 and the optical axis of the image acquisition device 20 to ensure that the supplementary lighting range can cover the field of view of the image acquisition device 20. In this embodiment, the supplementary light source 30 can cover the field of view of the image acquisition device 20 when the image acquisition device 20 is at its radially closest position (corresponding to the closest working distance of the image acquisition device 20) and its radially farthest position (corresponding to the farthest working distance of the image acquisition device 20).

[0056] The docking monitoring equipment also includes a light source control device and a camera control device, used to control the supplementary light source 30 and the camera respectively. The light source control device and the camera control device can be integrated and remotely controlled via software. The light source control device can autonomously adjust the brightness of the supplementary light source 30 according to the position of the gimbal camera 80. For example, when the gimbal camera 80 is close to the water surface, the light source control device controls to reduce the brightness of the supplementary light source 30; when the gimbal camera 80 is far from the water surface, the light source control device controls to increase the brightness of the supplementary light source 30.

[0057] The light source control unit and camera control unit are deployed in a remote control room. See also Figure 4 The software interface of the display device 52 can clearly show the screens of the four docking positions, and can adjust the camera's zoom, focus, aperture, scan, etc., and can adjust the camera's tilt angle.

[0058] The docking monitoring equipment also includes: a lifting control device, mainly used to control the up and down movement of the four lifting platforms 73; and a motor drive control device 74 with a speed controller as its core, including a DC geared motor, driver, and other components, to achieve unified automated control of the lifting platforms 73. The hardware of the control device is integrated into a control console, which is deployed in an open area next to the test water tank 10. Simultaneously, to facilitate remote visual operation and observation, a display device 52 is also deployed on this control console.

[0059] See Figure 11 The supplementary light source 30 includes an inner ring LED group located in the inner ring and an outer ring LED group located in the outer ring, with the inner ring LED group located radially inside the outer ring LED group.

[0060] The inner ring LED group includes multiple inner ring LEDs 310 distributed circumferentially, and the outer ring LED group includes multiple outer ring LEDs distributed circumferentially. The angle between the optical axis of the inner ring LEDs 310 and the optical axis of the image acquisition device 20 is different from the angle between the optical axis of the outer ring LEDs and the optical axis of the image acquisition device 20.

[0061] The inner ring LED group comprises multiple inner ring LED groups 31 spaced apart. Each inner ring LED group 31 includes two inner ring LEDs 310 whose optical axes are parallel to each other and arranged adjacently. "Adjacently arranged" here can be understood as the distance between the optical axes of the two inner ring LEDs 310 being less than or equal to the radius of the LED. The optical axes of each inner ring LED 310 form the same first angle with the optical axis of the image acquisition device 20.

[0062] The outer ring LED group includes a first outer ring LED group and a second outer ring LED group. The optical axes of each first outer ring LED 3210 in the first outer ring LED group form the same second angle with the optical axis of the image acquisition device 20. The optical axes of each second outer ring LED 3220 in the second outer ring LED group form the same third angle with the optical axis of the image acquisition device 20. The third angle is greater than or equal to the second angle. By configuring the supplementary light source 30 as described above, it is beneficial to ensure that the light within the field of view of the image acquisition device 20 is uniform and stable when the image acquisition device 20 moves radially to different positions, thus ensuring that the image acquisition device 20 can always acquire clear image data.

[0063] In some embodiments, the first included angle can be 8-12°. The second included angle can be 13-17°; and the third included angle can be 13-18°.

[0064] The first outer ring LED group includes multiple first outer ring LED groups 321 spaced apart, each first outer ring LED group 321 including two first outer ring LEDs 3210 arranged adjacent to each other with parallel optical axes. The second outer ring LED group includes multiple second outer ring LED groups 322 spaced apart, each second outer ring LED group 322 including two second outer ring LEDs 3220 arranged adjacent to each other with parallel optical axes. The first outer ring LED groups 321 and second outer ring LED groups 322 are arranged circumferentially. Each first outer ring LED group 321 is located radially outside one of the inner ring LED groups 31 of the inner ring LED group. This arrangement further ensures that the light within the field of view of the image acquisition device 20 is uniform and stable when the image acquisition device 20 moves radially to different positions, thus ensuring that the image acquisition device 20 can always acquire clear image data.

[0065] Each LED can have a certain divergence angle. Specifically, the overlap between each group of LEDs and adjacent groups can be up to 60%.

[0066] exist Figure 11In the illustrated embodiment, the supplementary lighting source 30 has a total of 24 LED beads. The inner ring LED bead group includes 8 LED beads, forming 4 inner ring LED bead groups 31. The 4 inner ring LED bead groups 31 are respectively positioned in the top, bottom, left, and right directions of the inner ring. The outer ring LED bead group includes 16 LED beads, wherein the first outer ring LED bead group has 8 LED beads, forming 4 first outer ring LED bead groups 321, and the second outer ring LED bead group has 8 LED beads, forming 4 second outer ring LED bead groups 322. The 4 first outer ring LED bead groups 321 are respectively positioned in the top, bottom, left, and right directions of the outer ring. The 4 second outer ring LED bead groups 322 are respectively positioned in the upper left, lower left, lower right, and upper right directions of the outer ring. The eight inner ring LEDs 310 of the inner ring LED group are tilted outward at 8°, the eight first outer ring LEDs 3210 of the first outer ring LED group are tilted outward at 13°, and the eight second outer ring LEDs 3220 of the second outer ring LED group are evenly distributed on the circumference at 18°. In this embodiment, it is further beneficial to ensure uniform and stable light within the field of view of the image acquisition device 20.

[0067] In some embodiments, the docking monitoring device may further include: a stereo calibration plate for calibrating multiple cameras underwater. See also Figure 12 The three-dimensional calibration plate 60 includes multiple calibration surfaces 61, and an array of marker frames 610 is formed on each calibration surface 61. Each marker frame 610 includes multiple marker points 611. The pattern formed by the multiple marker points 611 in each marker frame 610 is identical. Not all marker points 611 are located in the same row or column of the marker frames 610. In the illustrated embodiment, each marker frame 610 includes 8 marker points 611.

[0068] The number of calibration surfaces 61 can be greater than or equal to the number of cameras. When there are four cameras, the stereo calibration plate 60 can have a cube or cuboid structure, and there can be four calibration surfaces 61, which are formed on the four sides of the cube or cuboid structure.

[0069] Compared with a checkerboard-type calibration plate, this application uses a three-dimensional calibration plate 60 that includes multiple calibration surfaces 61, each calibration surface 61 forming an array of marker frames 610, and each marker frame 610 including multiple marker points 611, which can greatly improve the calibration accuracy.

[0070] Camera calibration can be divided into intrinsic parameter calibration for each camera and extrinsic parameter calibration for a multi-camera system. Compared with the traditional frame 731 calibration object, the stereo calibration board 60 is more portable and has higher precision, and can be used for the calibration of intrinsic and extrinsic parameters of multiple cameras.

[0071] When calibrating intrinsic parameters, each camera can take multiple frames of images containing the stereo calibration plate 60 at different angles and the same distance. Then, each frame of image is processed to obtain the intrinsic parameters of each camera.

[0072] Multi-camera extrinsic parameter calibration is used to determine the relative attitude relationships between camera coordinate systems, including translation and rotation parameters. During extrinsic parameter calibration, each camera photographs a stereo calibration board 60, calibrating all cameras as a whole, unifying the coordinate system, and simultaneously providing the phase and pose relationships of the four cameras.

[0073] During the calibration of multiple cameras, the camera extrinsic parameters can be calibrated by measuring a reference scale. This calibration requires simultaneous measurements of the reference scale by each camera pair. Using multi-angle, multi-position reference scale information, the relative positional relationships of the cameras are calculated through joint adjustment, unifying the coordinate systems of multiple cameras and completing the joint station setup for multiple cameras. Continuous online shooting of the desired area can be performed to acquire data, and the resulting images are then transferred to measurement software for processing.

[0074] When calibrating the extrinsic parameters, the first step is to acquire images of each calibration surface 61 of the stereo calibration plate 60 to obtain the three-dimensional coordinates of each marker point 611 in each marker frame 610 on each calibration surface 61 of the stereo calibration plate 60; the second step is to place the stereo calibration plate 60 within the common field of view of all cameras, so that each camera acquires a frame image containing the stereo calibration plate 60, and obtain the relative pose relationship between each camera and the stereo calibration plate 60 based on the images acquired by each camera; the third step is to determine the relative pose relationship between each camera based on the three-dimensional coordinates of each marker point 611 of the stereo calibration plate 60 obtained in the first step and the relative pose relationship between each camera and the stereo calibration plate 60; the fourth step is to obtain the extrinsic parameters of the multi-camera system.

[0075] Using the extrinsic parameter calibration method of this application embodiment, when calibrating extrinsic parameters, by selecting a stereo calibration plate 60 with a specific structure, the three-dimensional coordinates of each marker point 611 in each marker frame 610 on each calibration surface 61 of the stereo calibration plate 60 are first obtained. Then, by acquiring only one frame image containing the stereo calibration plate 60 from each camera, the extrinsic parameters of the entire camera system can be calculated. Because this application embodiment uses a stereo calibration plate 60 with a specific structure, the calibration accuracy is improved, allowing each camera to acquire only one image when calibrating extrinsic parameters, without needing to rotate the stereo calibration plate 60 and / or change the camera angle, making the operation very simple.

[0076] Extrinsic parameter calibration can be calculated using the principle of spatial resection. Spatial resection is based on point measurement of a single image, and its ideal projection imaging model is the pinhole imaging model in geometrical optics. When multiple cameras perform resection on the same control field, the transformation relationship between the control field coordinate system and each camera is obtained. Then, the transformation relationship between each camera can be calculated, thus completing the multi-camera extrinsic parameter calibration.

[0077] A single camera can be used to acquire data from a stereo calibration plate 60, such as... Figure 13 The control field data shown is illustrated. Four cameras were used simultaneously from four faces. Figure 13 By performing a resection of the stereo control field shown, the transformation relationship between the four camera coordinate systems and the same control field coordinate system can be obtained, thus completing the extrinsic parameter calibration between cameras. Specifically, the steps for calibrating the camera intrinsic parameters may include: taking images of the stereo calibration plate 60 from multiple angles and positions using the camera when it is not installed at the workstation. The number of images should be no less than 35, and the images should be imported into calibration software to calculate the ten intrinsic parameters of the camera. When calibrating the intrinsic parameters, each camera can take multiple frames containing the stereo calibration plate 60 from different angles and at the same distance, and then process each frame to obtain the intrinsic parameters of each camera.

[0078] The steps for camera extrinsic parameter calibration may include: installing and fixing the camera, placing the stereo calibration plate 60 within the camera's field of view. During calibration, it is not necessary for all cameras to capture images of the stereo calibration plate 60 at the same position. Multiple cameras can simultaneously capture images, allowing the relative pose relationship between the cameras and the stereo calibration plate 60 to be calculated. The extrinsic parameter calibration is then completed via coordinate system transfer. While the cameras remain stationary, the stereo calibration plate 60 can be rotated (ensuring it remains within the common field of view of all cameras) to obtain multiple sets of camera extrinsic parameter data. Finally, an average calculation is performed to ensure data accuracy.

[0079] This application also provides a docking system for underwater docking structures. The docking system includes a hoisting and launching device 13 and a docking monitoring device according to any embodiment of this application. The hoisting and launching device 13 is used to launch a second annular component 12 underwater so that the second annular component 12 docks and assembles with the first annular component 11; or it is used to hoist the second annular component 12 upward so as to separate the second annular component 12 from the first annular component 11.

[0080] This application also provides a docking method for underwater docking structures, which is implemented using the docking system of any embodiment of this application.

[0081] The docking method in this application embodiment includes steps S1 to S6.

[0082] Step S1: Obtain the first reference of the first annular component 11 and the second reference of the second annular component 12, and display them in the display device 52.

[0083] Step S2: Calibrate the multiple image acquisition devices 20.

[0084] Step S3: Use the hoisting and launching device 13 to launch the second annular component 12 underwater or to hoist the second annular component 12 upward.

[0085] Step S4: Control multiple image acquisition devices 20 to continuously move in the same direction as the second annular component 12 in the water, and continuously acquire images including the second annular component 12.

[0086] Step S5: Process the image to obtain the pose and angle of the second ring component 12.

[0087] Step S6: According to the first reference of the first annular component 11 and the second reference of the second annular component 12 displayed on the display device 52, adjust the hoisting and launching device 13 to change the position and angle of the second annular component 12 so that the first reference displayed on the display device 52 is aligned with the second reference.

[0088] In the docking method of this application, the user can observe the position and tilt angle of the second ring component 12 in real time during the underwater deployment of the second ring component 12 based on the image displayed on the display device 52, so as to use the hoisting and deployment device 13 to adjust the position and tilt angle of the second ring component 12 to a preset position and preset angle, thereby aligning the second ring component 12 with the first ring component 11.

[0089] In some embodiments, step S2, calibrating the multiple image acquisition devices 20 includes determining extrinsic parameters. The method for determining extrinsic parameters includes: step S21, acquiring images of each calibration surface of the stereo calibration board to obtain the three-dimensional coordinates of each marker point in each frame on each calibration surface of the stereo calibration board; step S22, placing the stereo calibration board within the common field of view of all cameras, allowing each camera to acquire a frame image containing the stereo calibration board, and obtaining the relative pose relationship between each camera and the stereo calibration board based on the images acquired by each camera; step S23, determining the relative pose relationship between each camera based on the three-dimensional coordinates of each marker point on the stereo calibration board obtained in step S21 and the relative pose relationship between each camera and the stereo calibration board, thereby obtaining the extrinsic parameters of the multi-camera system.

[0090] In some embodiments, the docking method further includes acquiring images at different radial positions to determine the optimal acquisition position.

[0091] The docking system and docking method of the present invention will be described in detail below.

[0092] Flange positioning pin docking tests were conducted on a simulated low-temperature heating reactor basket in a 12.7m×10.5m×3.5m water tank 10. The monitored object was the docking and disassembly of the four centering pins of the basket flange. Based on the monitoring site conditions, four sets of radial movement mechanisms 40 and four sets of lifting mechanisms 70 were installed around the site, with the installation positions evenly distributed at 90° intervals in the water tank 10.

[0093] The radial movement mechanism 40 has an installation length of 2.4m, and the overall height of the lifting mechanism 70 is approximately 4m. After the radial movement mechanism 40 and the lifting mechanism 70 are installed, the pan-tilt camera 80 is mounted on the lifting platform. Both the radial movement mechanism 40 and the lifting mechanism 70 are driven by rotary motors in both the X-axis (radial) and Y-axis (height) directions. Rotation can be controlled via software or a web interface, achieving a 360° angle. The gear at the lower part of the rotary motor forms a planetary gear structure relative to the main shaft gear, allowing the gear, the connected rotary motor, and the support to rotate along the main shaft. The rotation angle is determined by data observed by the visualization system, and the angle is adjusted through the rotary motor's control system to position the camera at the optimal monitoring position.

[0094] Each camera in the system needs to undergo integration and calibration before formal installation and use. Therefore, it is required that each camera can be independently tested and integrated even before complete installation. Thus, the design ensures that the interfaces of each camera are independent, allowing the cameras in the system to be used individually or simultaneously.

[0095] After adjusting the position, observe the imaging status of the PTZ camera 80 monitoring system, and adjust the focal length and aperture to achieve the best imaging effect.

[0096] This application embodiment uses a mesh design with four gimbal cameras 80 to detect docking at different locations, and to observe from multiple angles and positions, while ensuring docking accuracy.

[0097] This embodiment uses a lifting platform 73 to adjust the detection position of the gimbal camera 80, enabling the detection of docking objects of different sizes. Furthermore, the camera's focal length, aperture, and other parameters can be adjusted, providing a reference for various engineering projects. Using the visual monitoring method of the gimbal camera 80 allows for real-time monitoring with high efficiency, and the entire process is contactless, ensuring safety during docking operations.

[0098] Regarding the embodiments of the present invention, it should also be noted that, without conflict, the embodiments of the present invention and the features in the embodiments can be combined with each other to obtain new embodiments.

[0099] The above are merely specific embodiments of the present invention, but the scope of protection of the present invention is not limited thereto. The scope of protection of the present invention should be determined by the scope of the claims.

Claims

1. A docking monitoring apparatus for an underwater docking structure, the underwater docking structure comprising a first ring-shaped component located underwater and a second ring-shaped component for docking assembly with the first ring-shaped component, wherein, The second ring-shaped component is underwater launched by a launching device to be assembled with the first ring-shaped component, or is hoisted upward by a launching device to be disassembled from the first ring-shaped component, the first ring-shaped component is formed with a plurality of positioning members distributed in the circumferential direction and extending in the vertical direction, and the second ring-shaped component is correspondingly formed with a plurality of positioning matching members distributed in the circumferential direction and extending in the vertical direction, the second ring-shaped component and the first ring-shaped component are positioned by the positioning matching members and the positioning members being inserted into each other; The device comprises: a plurality of lifting mechanisms arranged around the first ring-shaped component underwater, each of the lifting mechanisms facing one of the positioning members; a plurality of image acquisition devices, each of the image acquisition devices being arranged on one of the lifting mechanisms, each of the lifting mechanisms being configured to drive the image acquisition device to move in the same direction as the second ring-shaped component during the process of the second ring-shaped component being raised or lowered underwater, so as to continuously acquire images containing the second ring-shaped component; and a display device for displaying the images acquired by the plurality of image acquisition devices.

2. The device according to claim 1, further comprising: a processor for processing the images containing the first ring-shaped component and the images containing the second ring-shaped component to obtain a first reference of the first ring-shaped component and a second reference of the second ring-shaped component, and display the first reference and the second reference in the display device.

3. The device according to claim 1, further comprising: a plurality of light supplement sources, each of the light supplement sources being used for supplementing light for a corresponding image acquisition device; 4. The apparatus of claim 3, further comprising: a plurality of gimbals, each of the gimbals being used for mounting an image acquisition device and a light supplement source, wherein the gimbals comprise: a base arranged on the lifting mechanism; a rotating shaft arranged on the base and capable of rotating along a vertical axis relative to the base; and two lens barrels arranged on opposite transverse sides of the rotating shaft, respectively, the two lens barrels being capable of independently rotating along a tilt axis relative to the rotating shaft; wherein the image acquisition device and the light supplement source are arranged in one of the lens barrels.

5. The apparatus of claim 3, wherein, The light supplement source comprises an inner ring lamp bead group located in an inner ring and an outer ring lamp bead group located in an outer ring, the inner ring lamp bead group comprises a plurality of inner ring lamp beads distributed in the circumferential direction, and the outer ring lamp bead group comprises a plurality of outer ring lamp beads distributed in the circumferential direction, wherein an included angle between an optical axis of the inner ring lamp bead and an optical axis of the image acquisition device is different from an included angle between an optical axis of the outer ring lamp bead and the optical axis of the image acquisition device.

6. The apparatus of claim 5, wherein, The inner ring lamp bead group comprises a plurality of inner ring lamp bead groups arranged at intervals, each of the inner ring lamp bead groups comprises two inner ring lamp beads arranged adjacent to each other with parallel optical axes, and an included angle between the optical axis of each of the inner ring lamp beads and the optical axis of the image acquisition device is the same.

7. The apparatus of claim 1, wherein, The image acquisition device is a camera, and the device further comprises: a stereo calibration board for calibrating a plurality of the cameras underwater; the stereo calibration board comprises a plurality of calibration surfaces, each of the calibration surfaces is formed with an array of mark frames, each of the mark frames comprises a plurality of mark points, and the patterns formed by the plurality of mark points in each of the mark frames are the same.

8. A docking system for a underwater docking structure, the underwater docking structure comprising a first ring-shaped component located underwater and a second ring-shaped component for docking assembly with the first ring-shaped component, the first ring-shaped component being formed with a plurality of positioning members distributed circumferentially and extending vertically, the second ring-shaped component being correspondingly formed with a plurality of positioning counterparts distributed circumferentially and extending vertically, the second ring-shaped component being positioned with the first ring-shaped component by the positioning counterparts and the positioning members; the docking system comprising: a lifting and launching device for launching the second ring-shaped component underwater to dock the second ring-shaped component with the first ring-shaped component; or for lifting the second ring-shaped component upward to disassemble the second ring-shaped component from the first ring-shaped component; and a docking monitoring device according to any one of claims 1-7.

9. A docking method for a underwater docking structure, the method being implemented by using the system of claim 8, the method comprising: step S1, obtaining a first reference of the first ring-shaped component and a second reference of the second ring-shaped component, and displaying the first reference and the second reference on a display device; step S2, calibrating the plurality of image acquisition devices; step S3, launching the second ring-shaped component underwater by using the lifting and launching device or lifting the second ring-shaped component upward; step S4, controlling the plurality of image acquisition devices to move with the second ring-shaped component in water continuously and continuously acquire images containing the second ring-shaped component; step S5, processing the images to obtain a pose and an angle of the second ring-shaped component, step S6, adjusting the lifting and launching device according to the first reference and the second reference of the first ring-shaped component and the second ring-shaped component displayed on the display device to change the pose and the angle of the second ring-shaped component, so that the first reference and the second reference displayed on the display device are aligned. In the step S2, calibrating the plurality of image acquisition devices includes determining extrinsic parameters, and the step of determining the extrinsic parameters comprises:

10. The method of claim 9, wherein, step S21, acquiring images of each calibration surface of a stereo calibration board to obtain three-dimensional coordinates of each marker point in each calibration frame on each calibration surface of the stereo calibration board; step S22, placing the stereo calibration board in the common field of view of all cameras, and causing each camera to acquire a frame of image containing the stereo calibration board, and obtaining a relative pose relationship between each camera and the stereo calibration board according to the images acquired by each camera; step S23, determining a relative pose relationship between each camera based on the three-dimensional coordinates of each marker point of the stereo calibration board obtained in step S21 and the relative pose relationship between each camera and the stereo calibration board, and obtaining extrinsic parameters of the multi-camera system. ​

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