A control method of a multi-legged bionic ship spraying robot

Abstract

The application discloses a control method of a multi-legged bionic ship spraying robot, and relates to the technical field of ship spraying. The method comprises the following steps: acquiring ship surface information of a current landing point and a next landing point of a leg, combining a posture of the robot, controlling an opening mode of an electromagnet, reading a pressure value of a pressure sensor to determine the suction force of the electromagnet on each leg, and adjusting the suction force of the electromagnet, so as to realize efficient adaptive control, ensure that the robot can cope with changes in the ship surface, provide a guarantee for reliable work of the robot, and achieve energy saving and consumption reduction. In addition, the central control system can determine a walking gait mode of the robot according to the current ship surface state, so as to ensure the operation ability and the moving ability of the robot on a complex surface. Meanwhile, the central control system controls the rotation of each joint of a mechanical arm, so that the spray gun moves uniformly relative to the ship surface, and uniform spraying is ensured. In addition, the method can automatically detect the spraying quality after spraying is completed.

Description

Technical Field

[0001] This invention relates to the field of ship painting technology, and in particular to a control method for a multi-legged biomimetic ship painting robot. Background Technology

[0002] Ships, as an important means of transportation, play a vital role in the national economy and daily life. Ships are made of steel. To prevent rust, corrosion, and biofouling, they are painted for protection. However, currently, most ship hull painting is done manually, which has many drawbacks, including high cost, low efficiency, poor quality, health hazards, and high risks. Therefore, there is an urgent need for automated painting devices and equipment to replace manual painting. For example, patent CN115228650A discloses a ship painting robot, and patent CN105689174A discloses an automated ship painting robot. Current ship painting robots are typically wheeled, floor-mounted robots, which are large and have relatively simple functions. Moreover, these wheeled, floor-mounted robots can only operate within the dock and cannot directly paint on the ship's vertical surfaces or load-bearing inclined surfaces. Summary of the Invention

[0003] The main objective of this invention is to provide a control method for a multi-legged biomimetic ship painting robot, which can effectively solve the technical problems in the background art.

[0004] To achieve the above objectives, the technical solution adopted by the present invention is as follows:

[0005] A control method for a multi-legged biomimetic ship painting robot, the multi-legged biomimetic ship painting robot including a spray gun, a fuselage, several legs, and a robotic arm. Several legs are arranged on the sides of the fuselage; a gimbal is provided on the upper surface of the fuselage, and the spray gun is connected to the gimbal via the robotic arm; each leg is omnidirectionally connected to an electromagnet via a ball joint assembly; the electromagnet is equipped with a pressure sensor; the fuselage is equipped with a first camera and a second camera; and a central control system is installed inside the fuselage.

[0006] The control method for this multi-legged biomimetic ship painting robot includes the following steps:

[0007] (1) The central control system establishes a three-dimensional coordinate system of XYZ with the horizontal plane as the XY plane;

[0008] (2) The first camera acquires the first image information around the current landing point of the leg, and the central control system obtains the first ship surface information based on the first image information in a three-dimensional coordinate system.

[0009] (3) The second camera acquires the second image information of the next landing point of the leg, and the central control system obtains the second ship surface information based on the second image information and the three-dimensional coordinate system.

[0010] (4) The central control system determines whether the surface of the second ship is a negative gravity surface or a positive gravity surface based on the surface information of the second ship;

[0011] (5) If the surface of the second ship is a negative gravity surface, then when the legs begin to fall towards the surface of the second ship, the electromagnet is started with an initial current I0, so that the electromagnet generates an initial magnetic force F0 = k(I0·W). 2 Where k is a constant, a parameter related to the coil cross-sectional area, core material, air gap, and other structural features; I0 is the initial coil current; and W is the number of coil turns. When the leg stops falling, the central control system gradually increases the electromagnet current I from the initial current I0 until the pressure value is reached. Where G is the total weight of the multi-legged bionic ship painting robot; n is the minimum number of legs that come into contact with the ship surface during the process; ΔN is the tolerance of the pressure sensor; θ2 is the angle between the second ship surface and the XY-dimensional plane; and μ is the friction coefficient of the ship surface.

[0012] Furthermore, in step (5), if the surface of the second ship is a negative gravity surface, when the legs stop falling, the central control system gradually increases the current I of the electromagnet from the initial current I0 until the pressure value is within a certain range. Within the range;

[0013] Step (5) further includes: if the surface of the second ship is a positive gravity surface, when the leg stops falling towards the surface of the second ship, the central control system gradually increases the current I of the electromagnet from 0 until the pressure value N is at a certain level. Within the range.

[0014] Furthermore, step (4) also includes determining whether the surface of the first ship is a negative gravity surface or a positive gravity surface;

[0015] In step (5), if both the first and second ship surfaces are negatively impacted surfaces, the pressure value will be calculated until the pressure value is reached. Where θ1 is the angle between the surface of the first ship and the XY-dimensional plane;

[0016] If the surface of the first vessel is a positive gravity surface and the surface of the second vessel is a negative gravity surface, then until the pressure value...

[0017] Furthermore, step (4) also includes determining whether the surface of the first ship is a negative gravity surface or a positive gravity surface;

[0018] In step (5), if both the first and second ship surfaces are positive gravity surfaces, then the pressure value is calculated.

[0019] If the surface of the first ship is a negative gravity surface, and the surfaces of the second ship are all positive gravity surfaces, until the pressure value...

[0020] Furthermore, three legs are symmetrically arranged on the left and right sides of the fuselage; the control method also includes that the central control system controls the six legs to move in an alternating triangular gait; at the same time, the central control system controls the robotic arm to make the spray gun move at a constant speed relative to the surface of the ship.

[0021] Furthermore, the top of the fuselage is equipped with the second camera; the belly of the fuselage is embedded with the first camera; the multi-legged bionic ship painting robot also includes an image preprocessing module and a painting defect detector; the control method further includes: the image preprocessing module performs image preprocessing on the first image information based on a joint bilateral filtering algorithm; and the painting defect detector then identifies the image to detect the painting quality.

[0022] Compared with the prior art, the present invention has the following beneficial effects:

[0023] Firstly, this invention obtains information about the current and next landing points of the legs on the ship's surface, combines this with the robot's gravity state, controls the activation mode of the electromagnets, and determines the magnitude of the electromagnet attraction on each leg by reading the pressure values ​​from the pressure sensors. This allows for efficient adaptive control, ensuring the robot can adapt to changes in the ship's surface and guaranteeing reliable operation. In particular, it ensures the robot is firmly magnetically attached to the ship's surface under negative gravity, while also achieving energy conservation and reduced consumption.

[0024] Secondly, the central control system controls the six legs to move in an alternating triangular gait, ensuring the robot's stability during movement. While the six legs move in this alternating triangular gait, the central control system fine-tunes the joints of the robotic arm, ensuring the spray gun moves at a uniform speed relative to the ship's surface, guaranteeing even coating and improving coating quality. Attached Figure Description

[0025] Figure 1 This is a three-dimensional structural diagram of the robot in this invention;

[0026] Figure 2 This is a schematic diagram of the leg disassembly in this invention;

[0027] Figure 3 This is an inverted schematic diagram of the ball joint in this invention.

[0028] Figure 4 In this invention, an inverted schematic diagram of an electromagnet is shown.

[0029] Figure 5 This is a disassembly diagram of the robotic arm in this invention.

[0030] Figure 6 This is the front view of the robot in this invention.

[0031] Figure 7 This is a block diagram of the central control system of the robot in this invention.

[0032] Figure 8 This is a force analysis diagram of the leg at the next landing point in this invention. Detailed Implementation

[0033] To make the technical means, creative features, objectives and effects of this invention easier to understand, the invention will be further described below in conjunction with specific embodiments.

[0034] Example 1

[0035] like Figures 1-6 As shown, a multi-legged biomimetic ship painting robot includes a fuselage 1, a gimbal 2, legs 3, a robotic arm 4, a spray gun 5, a first camera 91, and a second camera 92. The fuselage 1 has three legs symmetrically arranged on its left and right sides. Of course, the number and distribution of the legs are not limited to the above, and those skilled in the art can configure them as needed. The gimbal 2 is located on the upper surface of the fuselage 1, and the spray gun 5 is connected to the gimbal 2 via the robotic arm 4.

[0036] Two first cameras 91 are fixedly embedded in the abdomen of the body 1, with one first camera 91 offset to the left and the other first camera 91 offset to the right. A second camera 92 is movably mounted on the upper front part of the body 1. Preferably, both the first camera 91 and the second camera 92 are depth cameras, including but not limited to 3D sensing cameras from the ORBBEC Astra series.

[0037] like Figure 1 As shown, the structures of each leg 3 are the same. In this embodiment, the specific structure of the leg 3 located in the middle of the right side of the fuselage is described as an example.

[0038] like Figure 2 and Figure 5 As shown, for ease of description, a three-dimensional XYZ coordinate system is established, including mutually perpendicular XY planes, ZX planes, and ZY planes.

[0039] The leg 3 mainly includes a first section 31, a second section 32, and a third section 33. One end of the first section 31 is rotatably connected to the side of the fuselage 1 in the XY dimension via a first bus servo motor 61. The other end of the first section 31 is rotatably connected to the second section 32 in the ZX dimension via a second bus servo motor 62. The other end of the second section 32 is rotatably connected to the third section 33 in the ZX dimension via a third bus servo motor 63. The other end of the third section 33 is omnidirectionally connected to an electromagnet 35 via a ball joint connector 34.

[0040] like Figure 2 As shown, specifically, the first section 31 includes a cross-shaped plate 311, with inner folded plates 312 at both the upper and lower ends and outer folded plates 313 at both the front and rear ends. Preferably, the cross-shaped plate 311, the cross-shaped plate 311, and the inner folded plates 312 are integrally formed.

[0041] The second section 32 is an inverted C-shaped slat with its opening facing downwards. The second bus servo motor 62 and the third bus servo motor 63 are respectively fixedly embedded inside the left and right ends of the second section 32.

[0042] The third section 33 is an irregularly shaped groove with its opening facing the fuselage, and the lower end of the irregularly shaped groove is tapered in the ZX dimension.

[0043] like Figure 1 and Figure 2 As shown, the first bus servo motor 61, the second bus servo motor 62, and the third bus servo motor 63 are all dual-axis bus servo motors, which are existing products, and their specific structures will not be described in detail here. During assembly, the first bus servo motor 61 is fixedly embedded inside the fuselage 1, and its two output shafts are respectively fixedly connected to the two inner folding plates 312 of the first branch 31. The two output shafts of the second bus servo motor 62 are respectively fixedly connected to the two outer folding plates 313 of the first branch 31. The two output shafts of the third bus servo motor 63 are respectively fixedly connected to the interior of the front and rear sides of the upper end of the third branch 33. The ball joint assembly 34 at the lower end of the third branch 63 is omnidirectionally connected to an electromagnet 35.

[0044] like Figures 1-4As shown, specifically, the ball joint connecting assembly 34 includes a Y-shaped connecting plate 431, a horizontal plate 342, a ball joint seat 343, and a ball joint connecting rod 344. The upper ends of the two Y-shaped connecting plates 431 are detachably fixed to the interior of the lower front and rear sides of the third branch 63. The lower end of the Y-shaped connecting plate 431 is provided with a strip-shaped insertion hole, and the front and rear ends of the horizontal plate 342 are respectively inserted into the strip-shaped insertion holes of the two Y-shaped connecting plates 431. The upper end of the ball joint seat 343 is provided with a protruding edge, which is detachably fixed to the horizontal plate 342 by means of screws or the like. The lower end of the ball joint seat 343 penetrates through the horizontal plate 342 and is provided with a spherical groove 340. The upper end of the ball joint connecting rod 344 is integrally formed with a ball head, which can be omnidirectionally embedded in the interior of the spherical groove 340. Preferably, the lower end of the third branch 63 is also fixed with a protective shell 36 for enclosing the ball joint connecting assembly 34. It should be noted that the ball head of the ball joint connecting rod 344 and the spherical groove 340 of the ball head seat 343 are interference fits, meaning they will not rotate freely. This means that omnidirectional movement requires overcoming the frictional force of the interference fit. Preferably, during omnidirectional movement, the maximum angle between the central axes of the ball joint connecting rod 344 and the ball head seat 343 is 30° to 60° to avoid an excessively large angle between the magnetic attraction surface of the electromagnet 35 and the ship's surface before contact with the ship's surface.

[0045] Preferably, the electromagnet 35 is a hollow ring-shaped electromagnet, and a connecting post 351 is fixedly installed inside the hollow ring-shaped electromagnet by means of threads or other means. The lower end of the ball-head connecting rod 344 is detachably fixed to the connecting post 351 by means of threads or screws. A pressure sensor 353 is fixedly installed at the lower end of the connecting post 351, and the connecting post 351 has a hollow structure for wiring, which facilitates the laying of the electrical connection wires of the pressure sensor 353. The pressure sensor 353 includes, but is not limited to, a resistive thin-film pressure sensor. Resistive thin-film pressure sensors and ring-shaped electromagnets are existing products, and their specific structures will not be described in detail here.

[0046] like Figure 1 and Figure 5 As shown, the robotic arm 4 includes a first arm 41, a second arm 42, a third arm 43, and a fourth arm 44. The lower end of the first arm 41 is rotatably connected to the gimbal 2 in the ZY dimension via a fourth bus servo motor 64, and the upper end of the first arm 41 is rotatably connected to the second arm 42 in the ZY dimension via a fifth bus servo motor 65. The other end of the second arm 42 is rotatably connected to the third arm 43 in the ZY dimension via a sixth bus servo motor 66. The other end of the third arm 43 is rotatably connected to the fourth arm 44 in the ZX dimension via a seventh bus servo motor 67; a spray gun 5 is fixedly connected to the other end of the fourth arm 44.

[0047] like Figure 1 and Figure 5As shown, specifically, the robotic arm 4 includes a U-shaped connecting plate 8, an L-shaped connecting plate 9, and an irregularly shaped connecting plate 7. The irregularly shaped connecting plate 7 includes a base plate 71, one end of which has two first folding plates 72, and a socket for embedding a bus servo motor is formed between the two second folding plates. The other end of the base plate 71 has a second folding plate 73, which is opposite to the aforementioned socket.

[0048] The fourth bus servo motor 64, the fifth bus servo motor 65, the sixth bus servo motor 66, and the seventh bus servo motor 67 are all single-axis bus servo motors, existing products, and their specific structures will not be described in detail here. The fourth bus servo motor 64, the fifth bus servo motor 65, the sixth bus servo motor 66, and the seventh bus servo motor 67 are fixedly connected to a non-standard connecting plate 7 by screws. Taking the seventh bus servo motor 67 as an example, specifically, the seventh bus servo motor 67 is fixedly connected to the two first folding plates 72 of the non-standard connecting plate 7 by screws, with one end face of the seventh bus servo motor 67 abutting against the second folding plate 73.

[0049] The first arm 41 is formed by two U-shaped connecting plates 8 fixedly connected back-to-back with screws. One side of one U-shaped connecting plate 8 is rotatably connected to the second folded plate 73 of the irregular connecting plate 7 of the fourth bus servo motor 64 via a connecting shaft (not shown in the figure), and the other side is fixedly connected to the output shaft of the fourth bus servo motor 64. The other U-shaped connecting plate 8 is rotatably connected to the second folded plate 73 of the irregular connecting plate 7 of the fifth bus servo motor 64 via a connecting shaft (not shown in the figure), and the other side is fixedly connected to the output shaft of the fifth bus servo motor 64.

[0050] The second arm 42 is formed by fixing the U-shaped connecting plate 8 and the L-shaped connecting plate 9 together with screws. The other end of the L-shaped connecting plate 9 is fixedly connected to the irregular connecting plate 7 of the fifth bus servo 65; one side of the U-shaped connecting plate 8 is rotatably connected to the second folded plate 73 of the irregular connecting plate 7 of the sixth bus servo 66 via a connecting shaft (not shown in the figure), and the other side is fixedly connected to the output shaft of the sixth bus servo 66.

[0051] The third arm 43 is formed by screws connecting the irregular connecting plate 7 of the sixth bus servo 66 and the second folding plate 73 of the irregular connecting plate 7 of the seventh bus servo 67.

[0052] The fourth arm 44 is a planar plate, and the upper end of the fourth arm 44 is fixedly connected to the output shaft of the seventh bus servo motor, and the lower end of the fourth arm 44 is fixedly connected to the connecting rod 51 of the spray gun.

[0053] like Figure 1 , Figure 6 and Figure 7As shown, the central control system includes a microcomputer and a motion controller electrically connected via a bus. Preferably, the microcomputer is a Raspberry Pi microcomputer; the motion controller is an STM32 controller. The microcomputer is electrically connected to an IMU sensor, a tilt sensor, a wireless communication module, a first camera 91, a second camera 92, and multiple pressure sensors 353; the motion controller is electrically connected to a gimbal 2, multiple bus servo motors, a spray gun 5, and multiple electromagnets 35.

[0054] like Figure 1 , Figure 6 and Figure 7 As shown, the control method for the multi-legged biomimetic ship painting robot is roughly as follows:

[0055] A microcomputer (Raspberry Pi) reads the joint angles through the encoders of each bus servo motor and, combined with the forward kinematics model of the hexapod robot, calculates the robot's configuration. The forward kinematics model and configuration of the hexapod robot are existing technologies and will not be elaborated upon here. Relevant literature includes, but is not limited to: Bo You, Yaojin Fan and Daquan Liu; Fault-tolerant motion planning for a hexapod robot with single-leg failure using a foot force control method; Robotic Systems September-October 2022:1–11; DOI:10.1177 / 17298806221121070.

[0056] By combining data from the IMU sensor, the tilt sensor, and the robot's configuration, the robot's absolute pose is calculated.

[0057] The central control system controls the six legs to move alternately; at the same time, the central control system controls the robotic arm to make the spray gun move evenly relative to the surface of the ship.

[0058] Based on the robot's absolute pose, the current landing point of the legs, and the surface conditions of the ship at the next landing point, the expected value of the foot pressure of each leg of the robot is calculated.

[0059] The current of the electromagnet and the magnetic attraction force are adjusted so that the pressure of the pressure sensor 353 reaches the desired value, thereby allowing the robot to be firmly attached to the shell.

[0060] Therefore, the control of the aforementioned multi-legged biomimetic ship painting robot can be divided into the following three main parts:

[0061] (a) Mode of travel

[0062] The control method for the aforementioned multi-legged bionic ship painting robot includes: a central control system controlling the six legs to move in an alternating triangular gait to ensure the robot's stable movement. However, the alternating triangular gait is not uniform; therefore, while the six legs are moving in the alternating triangular gait, the central control system also controls the joints of the robotic arm to make fine adjustments, so that the spray gun moves evenly relative to the ship surface, ensuring uniform spraying and improving spraying quality. This movement control method is a conventional control method for multi-legged bionic robots, and those skilled in the art can implement it based on existing technology, so it will not be elaborated further here.

[0063] (II) The magnetic force of an electromagnet

[0064] like Figures 1 to 8 As shown, the control method for the above-mentioned multi-legged biomimetic ship painting robot also includes the following steps:

[0065] (1) The central control system establishes a three-dimensional coordinate system of XYZ with the horizontal plane as the XY plane;

[0066] (2) The first camera 91 acquires first image information around the current landing point of the leg. Based on the first image information, the central control system obtains first ship surface information based on a three-dimensional coordinate system. The first ship surface information mainly consists of three-dimensional coordinate data of a circular planar area with radius R1 radiating outward from the center of the current landing point of the leg. Radius R1 = r1 + d1, where r1 is the radius of the electromagnet, and preferably, d ranges from 1cm to 2cm.

[0067] (3) The second camera 92 acquires the second image information of the next landing point of the leg. Based on the second image information, the central control system obtains the second ship surface information based on the three-dimensional coordinate system. The second ship surface information is mainly the three-dimensional coordinate data of a circular planar area with radius R2 radiating outward from the center of the next landing point of the leg. Radius R2 = r1 + d2, where r1 is the radius of the electromagnet, and preferably, the value of d2 is in the range of 1cm to 2cm.

[0068] (4) The central control system determines whether the surface of the first ship or the surface of the second ship is a negative gravity surface or a positive gravity surface based on the surface information of the second ship.

[0069] (5) If the surface of the second ship is a negative gravity surface, then when the leg 3 begins to fall towards the surface of the second ship, the electromagnet 35 is activated with an initial current I0, so that the electromagnet 35 generates an initial magnetic force F0 = k(I0·W). 2 Where k is a constant, a parameter related to the coil cross-sectional area, core material, air gap, and other structural features; I0 is the initial coil current; and W is the number of coil turns. When the leg stops falling, the central control system gradually increases the current I of the electromagnet 35 from the initial current I0 and reads the pressure value of the pressure sensor 353 until the pressure value reaches the specified value. Where G is the total weight of the multi-legged bionic ship painting robot; n is the minimum number of legs that come into contact with the ship surface during the process; ΔN is the tolerance of the pressure sensor; θ2 is the angle between the second ship surface and the XY-dimensional plane; μ is the friction coefficient of the ship surface; in this embodiment, the robot has six legs 3 and moves in an alternating triangular gait, so n = 3.

[0070] Step (5) specifically includes

[0071] (5.1) If the surface of the second ship is a negative gravity surface, when the leg 3 begins to fall towards the surface of the second ship, the electromagnet 35 is activated with an initial current I0, so that the electromagnet 35 generates an initial magnetic force F0 = k(I0·W). 2 When leg 3 stops falling, the central control system gradually increases the current I of electromagnet 35 from the initial current I0, and reads the pressure value of pressure sensor 353 until the pressure value is within a certain range. Within the range.

[0072] (5.2) If the surface of the second vessel is a positive gravity surface, when leg 3 stops falling towards the surface of the second vessel, the central control system gradually increases the current I of the electromagnet from 0 and reads the pressure value of pressure sensor 353 until the pressure value N is within a certain range. Within the range.

[0073] Preferably, step (5.1) specifically includes:

[0074] (5.1.1) If both the first and second ship surfaces are negative gravity surfaces, when the leg 3 begins to fall toward the second ship surface, the electromagnet 35 is activated with an initial current I0, so that the electromagnet 35 generates an initial magnetic force F0 = k(I0·W). 2 When leg 3 stops falling, the central control system gradually increases the current I of electromagnet 35 from the initial current I0, and reads the pressure value of pressure sensor 353 until the pressure value reaches the specified value. Where θ1 is the angle between the surface of the first ship and the XY-dimensional plane.

[0075] (5.1.2) If the surface of the first ship is a positive gravity surface and the surface of the second ship is a negative gravity surface, when the legs begin to fall toward the surface of the second ship, the electromagnet 35 is activated with an initial current I0, so that the electromagnet 35 generates an initial magnetic force F0 = k(I0·W). 2 Where k is a constant, related to the coil cross-sectional area, core material, air gap, and other structural features; I0 is the initial coil current; and W is the number of coil turns. When leg 3 stops falling, the central control system gradually increases the current I of electromagnet 35 from the initial current I0 and reads the pressure value of pressure sensor 353 until the pressure value reaches the specified value.

[0076] Preferably, step (5.2) specifically includes:

[0077] (5.2.1) In step (5), if both the first and second ship surfaces are positive gravity surfaces, when the leg 3 stops falling towards the second ship surface, the central control system gradually increases the current I of the electromagnet from 0 and reads the pressure value of the pressure sensor 353 until the pressure value is reached.

[0078] (5.2.2) If the surface of the first ship is a negative gravity surface and the surfaces of the second ship are all positive gravity surfaces, when the leg 3 stops falling towards the surface of the second ship, the central control system gradually increases the current I of the electromagnet from 0 and reads the pressure value of the pressure sensor 353 until the pressure value is reached.

[0079] As can be seen, this invention obtains information about the ship's surface at the current and next landing points of the legs, combines this with the robot's gravitational state, controls the activation mode and magnetic force of the electromagnets, and indirectly determines the attraction force of the electromagnets in each leg by adjusting the pressure value of the pressure sensor. This achieves efficient adaptive control, ensuring that the robot can cope with changes in the ship's surface and guaranteeing reliable robot operation. In particular, it enables the robot to firmly adhere to the ship's surface by magnetic force under negative gravity, while also achieving energy saving and consumption reduction.

[0080] (III) Spraying quality inspection

[0081] The central control system also includes an image preprocessing module and a spraying defect detector; the control method of the above-mentioned multi-legged bionic ship spraying robot also includes: the image preprocessing module performs image preprocessing on the first image information based on the joint bilateral filtering algorithm; and then the spraying defect detector identifies the image and detects the spraying quality.

[0082] Preferably, the spraying defect detector includes, but is not limited to, a spraying defect detector based on a deep convolutional neural network (DNN) that identifies and detects spraying defects in images. This DNN consists of an input layer, convolutional layers, pooling layers, fully connected layers, and a softmax classifier. The first layer is the input layer, with the input data being a 128*128 grayscale image. This is followed by three alternating convolutional and pooling layers, with all convolutional layers using the same size feature filters. The first multilayer perceptron convolutional layer (MPC1) contains 12 feature maps, which are convolved with a 5*5 kernel on the input image, resulting in a 128*128 feature map. Then, in the pooling layer (S1), a 2*2 sampling kernel is used to pool the feature maps of the MPC1 layer, resulting in 12 64*64 feature maps. Similarly, the same process is performed on subsequent convolutional and pooling layers, with the S3 layer outputting the final two-dimensional feature map. At this point, the two-dimensional feature map is mapped to a one-dimensional vector to serve as the input to the fully connected layer, which contains 100 and 2 neurons respectively. The output of the fully connected layer is fed into a softmax classifier, and the position corresponding to the maximum component in the classifier's output is the classification result.

[0083] The foregoing has shown and described the basic principles, main features, and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The embodiments and descriptions in the specification are merely illustrative of the principles of the invention. Various changes and modifications can be made to the invention without departing from its spirit and scope, and all such changes and modifications fall within the scope of the present invention as claimed. The scope of protection of this invention is defined by the appended claims and their equivalents.

Claims

1. A control method for a multi-legged biomimetic ship painting robot, characterized in that: The multi-legged biomimetic ship painting robot includes a spray gun, a fuselage, several legs, and a robotic arm. Multiple legs are located on the sides of the fuselage. A gimbal is located on the upper surface of the fuselage, and the spray gun is connected to the gimbal via the robotic arm. Each leg is omnidirectionally connected to an electromagnet via a ball joint assembly. The electromagnet is equipped with a pressure sensor. The fuselage is equipped with a first camera and a second camera, and a central control system is installed inside the fuselage. The control method for this multi-legged biomimetic ship painting robot includes the following steps: (1) The central control system establishes a three-dimensional coordinate system of XYZ with the horizontal plane as the XY plane; (2) The first camera acquires the first image information around the current landing point of the leg, and the central control system obtains the first ship surface information based on the first image information in a three-dimensional coordinate system. (3) The second camera acquires the second image information of the next landing point of the leg, and the central control system obtains the second ship surface information based on the second image information in a three-dimensional coordinate system. (4) The central control system determines whether the surface of the second ship is a negative gravity surface or a positive gravity surface based on the surface information of the second ship; (5) If the surface of the second ship is a negative gravity surface, then when the legs begin to fall towards the surface of the second ship, the electromagnet is activated with an initial current I0 to generate an initial magnetic force. Where k is a constant, a parameter related to the coil cross-sectional area, core material, air gap, and other structural features; I0 is the initial coil current; and W is the number of coil turns. When the leg stops falling, the central control system gradually increases the electromagnet current I from the initial current I0 until the pressure value is reached. Where G is the total weight of the multi-legged bionic ship painting robot; n is the minimum number of legs that come into contact with the ship's surface during the process. θ2 is the tolerance of the pressure sensor; θ2 is the angle between the second ship surface and the XY plane; μ is the friction coefficient of the ship surface.

2. The control method for a multi-legged biomimetic ship painting robot according to claim 1, characterized in that: In step (5), if the surface of the second ship is a negative gravity surface, when the legs stop falling, the central control system gradually increases the current I of the electromagnet from the initial current I0 until the pressure value is within the range of { , Within the interval; Step (5) further includes: if the surface of the second ship is a positive gravity surface, when the leg stops falling towards the surface of the second ship, the central control system gradually increases the current I of the electromagnet from 0 until the pressure value N is at { , Within the interval.

3. The control method for a multi-legged biomimetic ship painting robot according to claim 2, characterized in that: Step (4) further includes determining whether the surface of the first ship is a negative gravity surface or a positive gravity surface; In step (5), if both the first and second ship surfaces are negatively impacted surfaces, the pressure value will be calculated until the pressure value is reached. Where θ1 is the angle between the surface of the first ship and the XY-dimensional plane; If the surface of the first vessel is a positive gravity surface and the surface of the second vessel is a negative gravity surface, then until the pressure value... .

4. The control method for a multi-legged biomimetic ship painting robot according to claim 2, characterized in that: Step (4) further includes determining whether the surface of the first ship is a negative gravity surface or a positive gravity surface; In step (5), if both the first and second ship surfaces are positive gravity surfaces, then the pressure value is calculated. ; If the surface of the first vessel is a negative gravity surface and the surface of the second vessel is a positive gravity surface, until the pressure value... .

5. A control method for a multi-legged biomimetic ship painting robot according to any one of claims 1-4, characterized in that: The fuselage has three legs symmetrically arranged on its left and right sides respectively; the control method also includes that the central control system controls the six legs to move in an alternating triangular gait; at the same time, the central control system controls the robotic arm to make the spray gun move at a constant speed relative to the surface of the ship.

6. The control method for a multi-legged biomimetic ship painting robot according to claim 1, characterized in that: The top of the fuselage is provided with the second camera; the belly of the fuselage is embedded with the first camera; the multi-legged bionic ship painting robot also includes an image preprocessing module and a painting defect detector; the control method also includes: the image preprocessing module performs image preprocessing on the first image information based on the image preprocessing algorithm of the joint bilateral filtering algorithm; and then the painting defect detector identifies the image and detects the painting quality.

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