A wireless charging system and method for underwater robots based on visual positioning

Abstract

The present invention discloses a wireless charging system and method for underwater robots based on visual positioning, and relates to the technical field of underwater robot charging. The technical points of the present invention include: the system includes an underwater wireless charging device and an underwater robot; wherein the underwater wireless charging device includes a positioning Aruco two-dimensional code, a vertical positioning rod, a wireless charging transmitting module, six supporting and fixing "Y"-shaped frames, and two permanent magnets; the frame of the underwater robot is a "Y"-shaped frame composed of three-layer horizontal plates, two left and right upper side plates, and two left and right lower side plates, and the frame includes a buoyancy block, an electronic compartment, a thruster, a battery compartment, a mechanical claw, a wireless charging receiving module, and a horizontal metal positioning rod; the method is implemented based on the system, and visual positioning is used to assist the underwater robot to dock with the underwater wireless charging device. The present invention improves the success rate and efficiency of docking between the underwater robot and the underwater wireless charging device, and easily realizes reliable charging of the underwater robot.

Description

Technical Field

[0001] The present invention relates to the technical field of underwater robot charging, and in particular to an underwater robot wireless charging system and method based on visual positioning. Background Art

[0002] The use of long-endurance submersibles can collect more environmental data that surface ships or submarines cannot collect. At present, submersibles need to surface to nearby ships or land bases to charge. There are two main traditional ways of power supply. One is to salvage underwater equipment ashore, replace new batteries or charge the batteries by wire; the other is to perform underwater wet plug-in charging on power supply platforms such as ships and seabed base stations through cable systems. The first method requires manual operation, has a low degree of automation, poor charging concealment, and can easily expose underwater equipment to targets; the wet plug-in method has a complex operation and maintenance process and is costly. Due to the large plug-in force, the interface is severely worn, which is prone to leakage accidents, and the reliability and safety are not high.

[0003] Traditional power supply methods limit the endurance and mission execution capabilities of underwater equipment. Wireless power transmission technology breaks the inherent pattern of traditional wired power transmission and gets rid of the constraints of redundant wires, making the power supply and charging equipment completely isolated, and the power supply circuit and charging circuit are independently packaged, which better solves the problems of wired power transmission, such as exposed wires, easy contact sparks, and poor mobility. For underwater robots without cable power supply, because the energy of their own energy storage modules is limited, they are generally unable to operate underwater for a long time. In order to improve the working efficiency and operating range of underwater robots, it is necessary to study underwater docking and wireless charging technologies for underwater robots.

[0004] For underwater vehicles, it is very important to identify the correct berth and measure the distance. Unlike traditional optical sensing equipment, the optical vision system of underwater robots not only needs to have the ability to obtain optical images and video information, but also should have the functions of processing, feature extraction, and classification and recognition of image and video information.

[0005] However, the existing technologies for charging and docking underwater robots have low success rates and efficiency, and some technologies have too high hardware requirements, making it difficult to achieve reliable charging of underwater robots. Summary of the invention

[0006] To this end, the present invention proposes a wireless charging system and method for an underwater robot based on vision positioning to solve the above problems.

[0007] According to one aspect of the present invention, there is provided an underwater robot wireless charging system based on visual positioning, the system comprising an underwater wireless charging device and an underwater robot; wherein:

[0008] The underwater wireless charging device includes a positioning Aruco QR code, a vertical positioning rod, a wireless charging transmitter module, six supporting and fixing "Y"-shaped frames, and a rectangular bottom plate; wherein the positioning Aruco QR code is connected to the vertical positioning rod; the vertical positioning rod is vertically fixed on one side of the long side of the rectangular bottom plate; the wireless charging transmitter module is fixed on the rectangular bottom plate; two supporting and fixing "Y"-shaped frames are fixed on each short side of the rectangular bottom plate, and two supporting and fixing "Y"-shaped frames are fixed on the other long side of the rectangular bottom plate away from the vertical positioning rod;

[0009] The frame of the underwater robot is a "Y"-shaped frame consisting of three-layer horizontal plates, two left and right upper side plates, and two left and right lower side plates. The upper side plates and the lower side plates are fixedly connected. The three-layer horizontal plates include a first layer plate, a second layer plate, and a third layer plate. The first layer plate and the second layer plate are used to connect the left and right upper side plates, and the third layer plate is used to connect the left and right lower side plates.

[0010] The frame of the underwater robot includes a buoyancy block, an electronic compartment, a propeller, and a wireless charging receiving module; wherein the buoyancy block is placed above the first layer of the board, the electronic compartment is embedded in the middle of the first layer of the board, and the center line is flush with the first layer of the board; the propeller is used to provide power for the movement of the underwater robot; the wireless charging receiving module is placed under the third layer of the board;

[0011] During docking, the four supporting and fixing "Y"-shaped frames on the short sides of the rectangular bottom plate cooperate with the two lower side plates to ensure the lateral stability of the underwater robot; after docking, the wireless charging transmitting module and the wireless charging receiving module are wirelessly connected to charge the underwater robot.

[0012] Furthermore, the frame of the underwater robot also includes a horizontal metal positioning rod, and the horizontal metal positioning rod is connected between the left and right third layer plates.

[0013] Furthermore, the underwater wireless charging device also includes two permanent magnets, which are respectively placed on two supporting and fixed "Y"-shaped frames on the other long side of the rectangular bottom plate, and are used to adsorb and fix the horizontal metal positioning rod during docking to ensure the longitudinal stability of the underwater robot.

[0014] Furthermore, the frame of the underwater robot also includes a mechanical claw, which is placed on the third layer of the board and is used to clamp the vertical positioning rod during docking to ensure the vertical stability of the underwater robot.

[0015] Furthermore, a camera, a wireless transmission module and a controller are placed in the electronic warehouse; wherein the camera is connected to the wireless transmission module, and the controller is connected to the wireless transmission module and the thruster respectively.

[0016] Furthermore, the frame of the underwater robot also includes a battery compartment, which is embedded in the middle of the second layer of the board, with the center line flush with the second layer of the board, and is used to supply power to the electronic compartment, the thruster and the mechanical claw.

[0017] Furthermore, the thrusters include six thrusters, four of which are respectively placed at the four corners of the lower surface of the first layer of board, and two are placed in the middle of the first layer of board.

[0018] According to another aspect of the present invention, a method for wireless charging of an underwater robot based on visual positioning is provided, the method is implemented based on the underwater robot wireless charging system, the underwater robot wireless charging system comprises an underwater wireless charging device and an underwater robot; wherein the underwater wireless charging device comprises a positioning Aruco two-dimensional code and a wireless charging transmitting module; the underwater robot comprises an electronic compartment and a wireless charging receiving module, wherein a camera, a wireless transmission module and a controller are placed in the electronic compartment;

[0019] The method comprises the following steps:

[0020] Step 1: Obtain the location of the underwater wireless charging device;

[0021] Step 2: Move the underwater robot close to the underwater wireless charging device, and stop moving when the image captured by the camera carried in the electronic compartment of the underwater robot contains the Aruco QR code;

[0022] Step 3: Process the image containing the Aruco QR code to obtain the position coordinates and attitude angle of the underwater robot relative to the underwater wireless charging device; specifically, take the center of the Aruco QR code on the underwater wireless charging device as the coordinate origin, X W The axis is horizontal to the right in the Aruco QR code plane, Y W The axis is vertically upward in the Aruco QR code plane, and the Z axis is established according to the right-hand rule. W Axis, establish coordinate system O W -X W Y W Z W ; Take the optical center of the camera as the origin of the camera coordinate system and establish the camera coordinate system O C -X C Y C Z C ; Use the PNP algorithm to solve the coordinate system O W -X W Y W Z W To the camera coordinate system O C -X C Y C Z CThe rotation matrix and translation matrix of the underwater robot are used to obtain the position coordinates and attitude angle of the underwater robot relative to the underwater wireless charging device, wherein the attitude angle includes a yaw angle, a roll angle, and a pitch angle;

[0023] Step 4: Adjust the position of the underwater robot to the first position and the posture to the first posture; wherein the first position is: the camera optical center coordinate O C In the coordinate system O W -Y W Z W In-plane, i.e. O C To Y W The perpendicular line of the axis and O W -Y W Z W The plane angle is 0 degrees; C To X W Axis perpendicular to plane O W -X W Z W The angle is between 10-30 degrees; the first posture is: the pitch angle is 180°, the yaw angle is 0°, and the roll angle is 0°;

[0024] Step 5: Make the underwater robot move toward the underwater wireless charging device parallel to Z W The underwater robot moves in the direction of the axis. When the relative distance between the underwater robot and the underwater wireless charging device is Z W When the axis component reaches the preset distance threshold, the underwater robot falls vertically. C To X W Axis perpendicular to plane O W -X W Z W The angle is decreasing, Z C Axis and Z W The axes coincide with each other, that is, O C To X W Axis perpendicular to plane O W -X W Z W When the angle is 0 degrees, the underwater robot and the underwater wireless charging device are docked and charging is started.

[0025] Furthermore, in step 5, C To X W Axis perpendicular to plane O W -X W Z W The angle is decreasing, and the O C To X W Axis perpendicular to plane O W -X W Z W Whether the angle exceeds 60 degrees, if it is judged to be yes, the underwater robot is made to fall vertically until OC To X W Axis perpendicular to plane O W -X W Z W When the angle is less than 60 degrees, the robot moves forward or backward horizontally again; and the underwater robot is at a predetermined horizontal distance from the underwater wireless charging device.

[0026] Furthermore, whether the output power of the underwater wireless charging device is normal is used to verify whether the underwater wireless charging device and the underwater robot are docked.

[0027] The beneficial technical effects of the present invention are:

[0028] The present invention proposes a system and method for wireless charging of an underwater robot based on visual positioning, which effectively improves the success rate and efficiency of docking between the underwater robot and the underwater wireless charging device. The implementation method is simple, the calculation amount is small, and reliable charging of the underwater robot is achieved.

[0029] The present invention uses visual positioning to assist the underwater robot in docking with the underwater wireless charging device, thereby improving the success rate and efficiency of the docking between the underwater robot and the underwater wireless charging device, thereby performing stable wireless charging and improving the endurance and working range of the underwater robot. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] The present invention can be better understood by referring to the description given below in conjunction with the accompanying drawings, which together with the following detailed description are included in this specification and form a part of this specification, and are used to further illustrate the preferred embodiments of the present invention and explain the principles and advantages of the present invention.

[0031] Figure 1 This is a structural diagram of a wireless charging system for an underwater robot based on visual positioning according to an embodiment of the present invention;

[0032] Figure 2 This is a schematic diagram of a wireless charging system for an underwater robot based on visual positioning after docking according to an embodiment of the present invention;

[0033] Figure 3 Schematic diagram of a multi-view underwater wireless charging device in an embodiment of the present invention;

[0034] Figure 4 This is a flow chart of a method for wireless charging of an underwater robot based on visual positioning according to an embodiment of the present invention;

[0035] Figure 5 Schematic diagram of two coordinate systems in an embodiment of the present invention;

[0036] Figure 6 is a schematic diagram of an underwater robot in a first position and a first posture according to an embodiment of the present invention;

[0037] Figure 7 is the relative distance Z between the underwater robot and the underwater wireless charging device in the embodiment of the present invention W Schematic diagram of an axis component reaching a preset distance threshold. DETAILED DESCRIPTION

[0038] In order to enable those skilled in the art to better understand the scheme of the present invention, exemplary implementations or embodiments of the present invention will be described below in conjunction with the accompanying drawings. Obviously, the described implementations or embodiments are only implementations or embodiments of a part of the present invention, not all of them. Based on the implementations or embodiments of the present invention, all other implementations or embodiments obtained by ordinary technicians in the field without creative work should fall within the scope of protection of the present invention.

[0039] The embodiment of the present invention provides a wireless charging system for an underwater robot based on visual positioning, such as Figure 1 As shown, the system includes an underwater wireless charging device 1 and an underwater robot 2; wherein the underwater wireless charging device 1 includes a positioning Aruco QR code 11, a vertical positioning rod 12, a wireless charging transmitter module 13, six supporting and fixing "Y"-shaped frames 14, two permanent magnets 15, and a rectangular bottom plate 16; wherein the positioning Aruco QR code 11 is connected to the vertical positioning rod 12, specifically, the positioning Aruco QR code 11 is connected to the L-shaped rod through bolts, and then connected to the vertical positioning rod 12 through a right-angle sleeve; the vertical positioning rod 1 2 is vertically fixed on one side of the long side of the rectangular bottom plate 16; the wireless charging transmitter module 13 is fixed on the rectangular bottom plate 16, and its DC power supply is directly provided by the constant voltage DC power supply on the shore, and the two can be connected by a cable; two supporting and fixing "Y"-shaped frames 14 are fixed on each short side of the rectangular bottom plate 16, and two supporting and fixing "Y"-shaped frames 14 are fixed on the other long side of the rectangular bottom plate 16 away from the vertical positioning rod 12, and two permanent magnets 15 are respectively placed on the two supporting and fixing "Y"-shaped frames 14 on the other long side of the rectangular bottom plate 16;

[0040] The frame of the underwater robot 2 is a "Yue"-shaped frame composed of three-layer horizontal plates, two left and right upper side plates 29, and two left and right lower side plates 212. The upper side plates 29 and the lower side plates 212 are fixedly connected. The three-layer horizontal plates include a first layer plate 22, a second layer plate 25, and a third layer plate 27. The first layer plate 22 and the second layer plate 25 are used to connect the left and right upper side plates 29, and the third layer plate 27 is used to connect the left and right lower side plates 212.

[0041] The frame of the underwater robot 2 includes a buoyancy block 21, an electronic compartment 23, a thruster 24, a battery compartment 26, a mechanical claw 28, a wireless charging receiving module 210, and a horizontal metal positioning rod 211; wherein the buoyancy block 21 is placed above the first layer 22, the electronic compartment 23 is embedded in the middle of the first layer 22, and the center line is flush with the first layer 22, and a camera, a wireless transmission module and a controller are placed in the electronic compartment 23; the thrusters 24 include six, four of which are placed at the four corners of the lower surface of the first layer 22, and the thrusters 24 are placed at the four corners of the lower surface of the first layer 22. The central axis is perpendicular to the angular bisector of the first layer 22, and the two are placed in the middle of the first layer 22. The propeller 24 is used to provide power for the underwater robot 2 to move. The battery compartment 26 is embedded in the middle of the second layer 25, and the central line is flush with the second layer 25, and is used to supply power to the electronic compartment 23, the propeller 24 and the mechanical claw 28. The mechanical claw 28 is placed on the third layer 27. The wireless charging receiving module 210 is placed under the third layer 27. The horizontal metal positioning rod 211 is connected between the left and right third layers 27.

[0042] When docking, the four supporting and fixing "Y"-shaped frames 14 on the short sides of the rectangular bottom plate 16 cooperate with the two lower side plates 212 to ensure the lateral stability of the underwater robot 2; the two permanent magnets 15 adsorb and fix the horizontal metal positioning rod 211 to ensure the longitudinal stability of the underwater robot 2; the mechanical claws 28 close and clamp the vertical positioning rod 12 to ensure the vertical stability of the underwater robot 2 and prevent it from floating upward and leaving the underwater wireless charging device 1. The supporting and fixing "Y"-shaped frame 14 reduces the difficulty of the underwater robot 2 landing on the underwater wireless charging device 1, while avoiding collision with other devices such as the coil.

[0043] After docking, the wireless charging transmitting module 13 and the wireless charging receiving module 210 are wirelessly connected to work to charge the underwater robot 2. Figure 2 shown.

[0044] In this embodiment, preferably, the wireless transmission module in the electronic warehouse 23 is selected from a model such as Raspberry Pi3 Model B; the camera is a 100-degree wide-angle USB camera, and the camera is connected to the wireless transmission module; the camera can be mounted on a gimbal, and the gimbal is selected from a model such as MG90S 90-degree steering gear; the controller is respectively connected to the wireless transmission module and the propeller 24, and the model is selected from PixHawk. Further, the electronic warehouse 23 can also include a power carrier module with a transmission rate of 100Mbps and a transmission distance of 300m, which is used to connect to a PC.

[0045] In this embodiment, preferably, the model of the thruster 24 is, for example, T200; the clamping force of the mechanical claw 28 is, for example, 90-150N, and the use depth is less than or equal to 300m.

[0046] In this embodiment, preferably, the front cover of the electronic compartment 23 is a transparent acrylic hemispherical cover.

[0047] Furthermore, a protruding semicircular hole structure is provided in the middle of one long side of the rectangular bottom plate 16 for fixing the vertical positioning rod 12. Figure 3 shown.

[0048] Another embodiment of the present invention provides a method for wireless charging of an underwater robot based on visual positioning, and the method is implemented based on the above-mentioned wireless charging system of the underwater robot. Figure 4 As shown, the method comprises the following steps:

[0049] Step 1: Obtain the location of the underwater wireless charging device 1;

[0050] Step 2: Move the underwater robot 2 close to the underwater wireless charging device 1, and stop moving when the image captured by the camera carried in the electronic compartment 23 of the underwater robot 2 contains the Aruco QR code;

[0051] Step 3: Process the image containing the Aruco QR code. At this time, the center of the positioning Aruco QR code 11 on the underwater wireless charging device 1 is used as the coordinate origin. W The axis is horizontal to the right in the Aruco QR code 1 plane, Y W The axis is vertically upward in the Aruco QR code 11 plane, and the Z is established according to the right-hand rule. W Axis, establish coordinate system O W -X W Y W Z W ; Take the optical center of the USB camera in the electronic compartment 23 of the underwater robot 2 as the origin of the camera coordinate system, and establish it according to the general provisions of the camera coordinate system, that is, Z C Axis is parallel to the optical axis, Y C The axis is vertically downward, and the X C Axis, establish the camera coordinate system O C -X C Y C Z C ,like Figure 5 shown.

[0052] Using the PNP algorithm, solve the coordinate system O W -X W Y W Z W To the camera coordinate system O C -X C Y C Z CThe rotation matrix and translation matrix are obtained to obtain the position coordinates and attitude angles (yaw angle, roll angle, pitch angle) of the underwater robot relative to the underwater wireless charging device.

[0053] Step 4: Adjust the robot posture to the first position and the first posture; wherein the first position is the optical center coordinate O of the robot camera. C In the world coordinate system O W -Y W Z W In-plane, i.e. O C To Y W The perpendicular line of the axis and O W -Y W Z W The plane angle is 0 degrees; C To X W Axis perpendicular to plane O W -X W Z W The angle is between 10 and 30 degrees. The first posture is: According to the coordinate system definition, the robot's pitch angle (pitch) is 180 degrees, the yaw angle (yaw) is 0 degrees, and the roll angle (roll) is 0 degrees. Figure 6 shown.

[0054] Step 5: After adjusting to the first position and the first posture, the optical center O of the camera of the underwater robot 2 is determined again. C To Y W The perpendicular line of the axis and O W -Y W Z W Is the plane angle between 0 and O? C To X W Axis perpendicular to plane O W -X W Z W Whether the angle is between 10 degrees and 30 degrees, if it is judged to be yes, the underwater robot 2 and the underwater wireless charging device 1 are longitudinally aligned; if it is judged to be no, the underwater robot 2 is adjusted according to the real-time measured position relative to the underwater wireless charging device 1 until it meets the first position and the first posture requirements.

[0055] Step 6: After adjusting to the first position and the first posture, the underwater robot 2 moves toward the underwater wireless charging device 1 in parallel with the Z W The underwater robot 2 moves in the direction of the axis, when the relative distance Z between the underwater wireless charging device 1 and the underwater robot 2 is W When the axis component reaches the preset distance threshold, such as Figure 7 As shown, (at this time, the robot 2 is no longer in the first posture, because its C To X W Axis perpendicular to plane O W -X WZ W The angle is not within the range of 10-30 degrees, and is actually larger than this angle), so that the underwater robot 2 falls vertically (the mechanical claw is in an open state before falling), C To X W Axis perpendicular to plane O W -X W Z W The angle will continue to decrease. Due to the setting of the mechanical structure position, when the horizontal positioning rod of the underwater robot 2 cooperates with the two Y-shaped frames behind the underwater wireless charging device 1 and the lower side plate edge of the underwater robot 2 cooperates with the four Y-shaped frames on both sides of the underwater wireless charging device 1, Z C Axis and Z W The axes just coincide, that is, O C To X W Axis perpendicular to plane O W -X W Z W The angle is exactly 0 degrees, at which time the positional relationship between the underwater robot 2 and the underwater wireless charging device 1 is docking completed; when the output power of the wireless charging device is normal, it means that the two are docked; after the docking is completed, the mechanical claws and permanent magnets are used to fix the two and charge them.

[0056] Among them, the relative distance Z between the underwater robot and the underwater wireless charging device is W When the axis component reaches the preset distance threshold, it is judged that C To X W Axis perpendicular to plane O W -X W Z W Whether the angle exceeds 60 degrees (after exceeding 60 degrees, the relative distance measurement error will be large, affecting the subsequent docking process), if it is judged to be yes, the robot falls vertically until O C To X W Axis perpendicular to plane O W -X W Z W The angle is less than 60 degrees (the relative distance Z between the underwater robot and the underwater wireless charging device at this time W The axis component will change relative to the previous one because the measurement error becomes smaller), and then it moves horizontally again (when the relative distance Z is measured W axis component is greater than a predetermined distance threshold) or retreat (when the relative distance Z W The axis component is less than a predetermined distance threshold), so that the underwater robot is at a predetermined horizontal distance from the underwater wireless charging device.

[0057] Although the present invention has been described according to a limited number of embodiments, it will be apparent to those skilled in the art, with the benefit of the above description, that other embodiments are contemplated within the scope of the invention thus described. The disclosure of the present invention is intended to be illustrative rather than restrictive of the scope of the invention, which is defined by the appended claims.

Claims

1. A wireless charging system for underwater robots based on visual positioning, characterized in that: It comprises an underwater wireless charging device (1) and an underwater robot (2); wherein: The underwater wireless charging device (1) comprises a positioning Aruco two-dimensional code (11), a vertical positioning rod (12), a wireless charging transmitter module (13), six supporting and fixing "Y"-shaped frames (14), and a rectangular bottom plate (16); wherein the positioning Aruco two-dimensional code (11) is connected to the vertical positioning rod (12); the vertical positioning rod (12) is vertically fixedly placed on one side of the long side of the rectangular bottom plate (16); the wireless charging transmitter module (13) is fixedly placed on the rectangular bottom plate (16); two supporting and fixing "Y"-shaped frames (14) are fixedly placed on each short side of the rectangular bottom plate (16), and two supporting and fixing "Y"-shaped frames (14) are fixedly placed on the other long side of the rectangular bottom plate (16) away from the vertical positioning rod (12); The frame of the underwater robot (2) is a "Y"-shaped frame composed of three-layer transverse plates, two left and right upper side plates (29), and two left and right lower side plates (212); the upper side plates (29) and the lower side plates (212) are fixedly connected; the three-layer transverse plates include a first layer plate (22), a second layer plate (25), and a third layer plate (27); the first layer plate (22) and the second layer plate (25) are used to connect the left and right upper side plates (29), and the third layer plate (27) is used to connect the left and right lower side plates (212); The frame of the underwater robot (2) comprises a buoyancy block (21), an electronic compartment (23), a propeller (24), and a wireless charging receiving module (210); wherein the buoyancy block (21) is placed above the first layer (22), the electronic compartment (23) is embedded in the middle of the first layer (22), and the center line is flush with the first layer (22); the propeller (24) is used to provide power for the movement of the underwater robot (2); and the wireless charging receiving module (210) is placed below the third layer (27); The frame of the underwater robot (2) further comprises a horizontal metal positioning rod (211), wherein the horizontal metal positioning rod (211) is connected between the left and right third layer plates (27); The frame of the underwater robot (2) also includes a mechanical claw (28), which is placed on the third layer board (27) and is used to clamp the vertical positioning rod (12) during docking to ensure the vertical stability of the underwater robot (2); The underwater wireless charging device (1) further comprises two permanent magnets (15), which are respectively placed on two supporting and fixing "Y"-shaped frames (14) on the other long side of the rectangular bottom plate (16) and are used to adsorb and fix the horizontal metal positioning rod (211) during docking to ensure the longitudinal stability of the underwater robot (2); During docking, the four supporting and fixing "Y"-shaped frames (14) on the short sides of the rectangular bottom plate (16) cooperate with the two lower side plates (212) to ensure the lateral stability of the underwater robot (2); after docking, the wireless charging transmitting module (13) and the wireless charging receiving module (210) are wirelessly connected to charge the underwater robot (2).

2. According to the vision-based positioning underwater robot wireless charging system of claim 1, it is characterized in that: A camera, a wireless transmission module and a controller are placed in the electronic compartment (23); wherein the camera and the wireless transmission module are connected, and the controller is connected to the wireless transmission module and the propeller (24) respectively.

3. According to the vision-based positioning underwater robot wireless charging system of claim 1, it is characterized in that: The frame of the underwater robot (2) also includes a battery compartment (26), which is embedded in the middle of the second layer of the board (25) with its center line flush with the second layer of the board (25) and is used to supply power to the electronic compartment (23), the thruster (24) and the mechanical claw (28).

4. The underwater robot wireless charging system based on visual positioning according to claim 1, characterized in that: The propellers (24) include six propellers, four of which are respectively placed at the four corners of the lower surface of the first layer of plate (22), and two are placed in the middle of the first layer of plate (22).

5. A wireless charging method for an underwater robot based on visual positioning, characterized in that: The method is implemented based on the underwater robot wireless charging system described in any one of claims 1 to 4; the method comprises the following steps: Step 1: obtaining the position of the underwater wireless charging device (1); Step 2: Move the underwater robot (2) close to the underwater wireless charging device (1), and stop moving when the image captured by the camera carried in the electronic compartment (23) of the underwater robot (2) contains the Aruco QR code; Step 3: Process the image containing the Aruco QR code to obtain the position coordinates and attitude angle of the underwater robot (2) relative to the underwater wireless charging device (1); specifically, the process includes: taking the center of the positioning Aruco QR code (11) on the underwater wireless charging device (1) as the coordinate origin, X W The axis is horizontal to the right in the Aruco QR code plane, Y W The axis is vertically upward in the Aruco QR code plane, and the Z axis is established according to the right-hand rule. W Axis, establish coordinate system O W -X W Y W Z W ; Take the optical center of the camera as the origin of the camera coordinate system and establish the camera coordinate system O C -X C Y C Z C ; Use the PNP algorithm to solve the coordinate system O W -X W Y W Z W To the camera coordinate system O C -X C Y C Z C The rotation matrix and translation matrix of the underwater robot are used to obtain the position coordinates and attitude angle of the underwater robot relative to the underwater wireless charging device, wherein the attitude angle includes a yaw angle, a roll angle, and a pitch angle; Step 4: adjusting the position of the underwater robot (2) to a first position and the posture to a first posture; wherein the first position is: the camera optical center coordinate O C In the coordinate system O W -Y W Z W In-plane, i.e. O C To Y W The perpendicular line of the axis and O W -Y W Z W The plane angle is 0 degrees; C To X W Axis perpendicular to plane O W -X W Z W The angle is between 10-30 degrees; the first posture is: the pitch angle is 180°, the yaw angle is 0°, and the roll angle is 0°; Step 5: Make the underwater robot (2) move toward the underwater wireless charging device (1) in parallel with Z W The underwater robot (2) moves in the direction of the axis, when the relative distance Z between the underwater wireless charging device (1) and the underwater robot (2) is W When the axis component reaches the preset distance threshold, the underwater robot (2) is made to fall vertically. C To X W Axis perpendicular to plane O W -X W Z W The angle decreases continuously until Z C Axis and Z W The axes coincide with each other, that is, O C To X W Axis perpendicular to plane O W -X W Z W When the angle is 0 degrees, the underwater robot (2) and the underwater wireless charging device (1) are docked and charging is performed.

6. The method for wireless charging of an underwater robot based on visual positioning according to claim 5, characterized in that: Step 5 O C To X W Axis perpendicular to plane O W -X W Z W The angle is decreasing, and the O C To X W Axis perpendicular to plane O W -X W Z W Whether the angle exceeds 60 degrees, if it is judged to be yes, the underwater robot (2) is made to fall vertically until O C To X W Axis perpendicular to plane O W -X W Z W When the angle is less than 60 degrees, the robot moves forward or backward horizontally again; and the underwater robot (2) is placed at a predetermined horizontal distance from the underwater wireless charging device (1).

7. A method for wireless charging of an underwater robot based on visual positioning according to claim 5 or 6, characterized in that: Whether the underwater wireless charging device (1) and the underwater robot (2) are docked is verified by checking whether the output power of the underwater wireless charging device (1) is normal.

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