Low-power adaptive curved surface laser rust removal device and rust removal method

Abstract

The application discloses a low-power self-adaptive curved surface laser rust removal device, which comprises a three-dimensional electric displacement table, a laser is installed on the three-dimensional electric displacement table, a wide band gap ultraviolet sensor and a binocular camera are arranged on one side of the laser from top to bottom, and the three-dimensional electric displacement table is connected with a microcontroller. The application further discloses a low-power self-adaptive curved surface laser rust removal method, and solves the problem that the existing rust removal mode cannot automatically and accurately follow the curved surface of a rust area to be ablated to adjust the defocusing amount in real time.

Description

Technical Field

[0001] This invention belongs to the field of laser processing technology, and relates to a low-power adaptive curved surface laser rust removal device. This invention also relates to a low-power adaptive curved surface laser rust removal method. Background Technology

[0002] Compared to traditional sandblasting and chemical rust removal methods, laser rust removal offers advantages such as faster removal speed and less pollution. Current laser rust removal methods use a parallel laser beam with a wavelength of 800-1064nm to scan the rust area line by line. Because parallel light is used, a pulsed laser with an average power greater than 200W or a continuous laser with an average power greater than 2000W is required as the rust removal light source. The cost and maintenance difficulty of the laser source increase exponentially with increasing power, making current laser rust removal technology expensive. While using a lens to focus a low-power parallel laser beam can significantly increase the power density of the spot, enabling it to ablate the rust layer, the issue of defocusing control needs to be addressed.

[0003] The existing technical solution uses a laser rangefinder to sense the defocus distance between the laser and the workpiece surface, maintaining a constant distance (focal length + preset defocus constant). However, this solution is costly and ignores the focal length drift error of the lens group caused by the thermal lensing effect. More importantly, it ignores the unevenness of oxide density and thickness in the rust area. Because the defocus amount cannot be dynamically adjusted during the rust removal process, uneven rust removal ("under-ablation" or "over-ablation") or even failure may occur. Summary of the Invention

[0004] The purpose of this invention is to provide a low-power adaptive curved surface laser rust removal device, which solves the problem that existing rust removal methods cannot automatically and accurately follow the curved surface of the rust area to be burned and adjust the defocusing amount in real time.

[0005] The purpose of this invention is to provide a low-power adaptive curved surface laser rust removal method.

[0006] The first technical solution adopted in this invention is a low-power adaptive curved surface laser rust removal device, including a three-dimensional electric displacement stage, a laser mounted on the three-dimensional electric displacement stage, a wide bandgap ultraviolet sensor and a binocular camera respectively arranged from top to bottom on one side of the laser, and a microcontroller connected to the three-dimensional electric displacement stage.

[0007] The second technical solution adopted in this invention is a low-power adaptive curved surface laser rust removal method, which specifically includes the following steps:

[0008] Step 1: Obtain information about the rust area of ​​the workpiece to be derusted;

[0009] Step 2: Construct the scanning area based on the image obtained in Step 1;

[0010] Step 3: Perform rust removal treatment within the scanned area constructed in Step 2.

[0011] The second technical solution of the present invention is further characterized by:

[0012] The specific process of step 1 is as follows:

[0013] Step 1.1: Obtain an RGB image of the workpiece to be rusted by capturing images of its surface using a binocular camera;

[0014] Step 1.2: The microcontroller constructs a three-dimensional shape model of the workpiece to be removed using a binocular stereo vision matching SGBM algorithm based on the RGB image of the workpiece to be removed, which is the depth information f(x, y, z) of the distance between the laser's output port and the three-dimensional surface of the workpiece to be removed.

[0015] Step 1.3: The microcontroller obtains an HSV array based on the RGB image of the workpiece to be derusted using a color block hue-saturation-brightness recognition algorithm, obtains a binary array using a binarization algorithm, and performs target segmentation to obtain the boundary position information s(x, y) of each rust area and the total number of rust areas K.

[0016] The specific process of step 2 is as follows:

[0017] Step 2.1: Define a square area with side length L as a scanning unit. Divide each rust area into scanning units, that is, take the minimum x coordinate, maximum x coordinate, minimum y coordinate and maximum y coordinate of the boundary position information s(x,y) of the rust area as the four vertices, construct a rectangular rust removal area, and start from the upper left corner of the rust removal area to divide the area into N rows and M columns of scanning unit grid.

[0018] Step 2.2: The microcontroller controls the x and y axes of the three-dimensional electric displacement stage to align the laser output port with the center of the first row and first column scanning unit of the first rust zone. Based on the depth information f(x, y, z), the microcontroller controls the z-axis of the three-dimensional electric displacement stage 1, ensuring that the initial distance W0 between the laser output port and the rust zone 32 is:

[0019] W0=μF0 (1);

[0020] Where μ is a constant coefficient and F0 is the room temperature focal length of the laser 11 lens group;

[0021] Step 2.3, Define G th Z is defined as the over-ablation ultraviolet radiation threshold. max Let Z be the z-axis coordinate value of the under-burning boundary line of defocusing amount. maxThe initial value is Z0, as shown in the following formula. The counter variable a, which represents the rust zone sequence number, is initialized to 1. The counter variable i, which represents the rust zone scan unit grid row number, is initialized to 1. The counter variable j, which represents the rust zone scan unit grid column number, is initialized to 2.

[0022] Z0=(μ-1)F0 (2).

[0023] The specific process of step 3 is as follows:

[0024] Step 3.1: Based on the two-dimensional galvanometer inside the laser, the laser beam scans a square scanning unit with a side length of L on the workpiece to be rusted point by point to remove rust. During this process, a wide-bandgap ultraviolet sensor continuously collects the ultraviolet component in the plasma radiation and records the total ultraviolet radiation G corresponding to the scanning unit.

[0025] Step 3.2: Use one of the binocular cameras to take a picture of the workpiece to be derusted to obtain an RGB image. Based on the HSV algorithm and binarization algorithm, obtain the binary array of the current scanning unit, that is, transform the image of the current scanning unit into only the white pixels that have been derusted and the black pixels that have not been derusted. Define the derusting rate η as the number of white pixels divided by the total number of pixels in the scanning unit. Detect and compare the derusting rate η with the derusting rate threshold η. th If η>=η th Then it is considered that the rust removal of this scanning unit is completed, and the G value at this time is recorded. Then the over-ablation ultraviolet radiation threshold G is obtained according to the following formula (3). th If the value is less than η, then proceed to step 3.3. th This is considered as under-ablation in this scanning unit, and the laser on the z-axis of the three-dimensional electric displacement stage moves closer to the workpiece to be removed by a step size D. z Assign Z max =Z max -D z Repeat step 3.1;

[0026] G th =αG (3);

[0027] In the formula, α is a constant coefficient;

[0028] Step 3.3: If j <= M, the microcontroller controls the three-dimensional electric displacement stage to move so that the laser output port is aligned with the center position of the scanning unit in the i-th row and j-th column of the a-th rust area, and then executes step 3.4; if j > M, the assignment statement j = 1 and i = i + 1 is executed, and then step 3.6 is executed.

[0029] Step 3.4: Based on the depth information f(x, y, z), control the z-axis of the three-dimensional electric displacement stage so that the distance between the laser's output port and the rust area is W. Based on the laser, perform rust removal on the current scanning unit. During this process, a wide-bandgap ultraviolet sensor continuously collects the ultraviolet component in the plasma radiation to obtain the total ultraviolet radiation G corresponding to the scanning unit. One camera in the binocular camera system takes an RGB image of the workpiece to be removed. The rust removal rates η and η' at this point are then calculated. th For comparison, if η >= η th If η < η, it means that the rust removal in this scanning unit has been successful. The assignment statement j = j + 1 is executed, and step 3.5 is followed. th This means an under-ablation state. In order for the laser to move closer to the workpiece to be removed by a step size D, z The assignment statement Z is executed. max =Z max -D z and W = F0 + Z max Repeat step 3.3;

[0030] Step 3.5, compare G and G th If G > G th This means an over-ablation state, requiring the laser to move away from the workpiece by a step size D. z The assignment statement Z is executed. max =Z max +D z Then proceed to step 3.6; if G <= G th Then proceed directly to step 3.6;

[0031] Step 3.6: If i <= N, then execute step 3.3; if i > N, then execute the amplitude statement i = 1 and a = a + 1, and then execute step 3.7.

[0032] Step 3.7: If a <= K, then proceed to step 3.3; if a > K, it means that all rusted areas have been derusted and the derusting process is complete.

[0033] The beneficial effects of this invention are that the low-power adaptive curved surface laser rust removal device utilizes a binocular camera for three-dimensional topographic pre-detection and real-time monitoring by the camera and a wide-bandgap ultraviolet sensor to adjust the defocus amount of any rusted curved surface in real time, thereby achieving adaptive and precise rust removal of any curved surface using focused light. The rust removal device provided by this invention has the advantages of low cost, high precision, and high adaptability. Attached Figure Description

[0034] Figure 1 This is a schematic diagram of the low-power curved surface adaptive laser rust removal device of the present invention;

[0035] Figure 2 This is a schematic diagram of the defocusing control principle used in the low-power curved surface adaptive laser rust removal method of the present invention;

[0036] Figure 3 This is the photoelectric response spectrum of the wide bandgap ultraviolet sensor used in the embodiment of the low-power curved surface adaptive laser rust removal method of the present invention;

[0037] Figure 4 It is the emission spectrum of iron plasma;

[0038] Figure 5 It is the emission spectrum of oxygen plasma;

[0039] Figure 6 This is a flowchart of the image processing algorithm in the low-power curved surface adaptive laser rust removal method of the present invention;

[0040] Figure 7 This is an effect diagram of an embodiment of the low-power curved surface adaptive laser rust removal method of the present invention.

[0041] In the figure, 1. Three-dimensional electric displacement stage, 2. Microcontroller, 11. Laser, 12. Laser beam, 13. Binocular camera, 14. Wide bandgap ultraviolet sensor, 15. Focus, 31. Workpiece to be derusted, 32. Rust zone, 42. Under-ablation boundary line. Detailed Implementation

[0042] The present invention will now be described in detail with reference to the accompanying drawings and specific embodiments.

[0043] The present invention provides a low-power adaptive laser rust removal processing device for curved surfaces, such as... Figure 1 , 2 As shown, it includes a laser 11, which is mounted on a three-dimensional electric displacement stage 1. The three-dimensional electric displacement stage 1 is connected to a microcontroller 2. A binocular camera 13 and a wide-bandgap ultraviolet sensor 14 are respectively installed on one side of the laser 11. The laser beam 12 emitted by the laser 11 irradiates the rust area 32, and the ablation and vaporization generate plasma radiation light signals.

[0044] The binocular camera 13 is connected to the microcontroller 2 for image recognition. The wide-bandgap ultraviolet sensor 14 is connected to the microcontroller 2 and compares the intensity of ultraviolet radiation from the plasma generated by ablation with a set ultraviolet radiation intensity threshold. Combined with the preprocessing of the binocular camera 13, it achieves dynamic feedback adjustment of the defocus amount.

[0045] This invention utilizes a dual-feedback system of a binocular camera 13 and a wide-bandgap ultraviolet sensor 14 to achieve adaptive real-time defocus adjustment for curved metal surfaces with varying rust thicknesses. This reduces the power of the laser rust removal machine's light source by an order of magnitude, significantly lowering the production, use, and maintenance costs of the equipment. By using the binocular camera to identify rusted areas and the microcontroller to plan the path, rust removal time is greatly saved, and rust removal efficiency is improved. In this invention, the origin of the xyz coordinate system is located at the room-temperature focal point of the laser.

[0046] The photoelectric response range of a typical wide-bandgap ultraviolet sensor is as follows: Figure 3 As shown; the spectral energy of iron (Fe) element plasma is mainly concentrated in the range of 232nm-276nm (e.g., Figure 4 As shown), it falls within the response range of wide-bandgap ultraviolet sensors such as GaN, AlGaN, and SiC; the spectral energy of oxygen (O) element plasma is mainly concentrated in the range of 615nm-928nm (e.g., Figure 5 As shown (indicated), this occurs outside the response range of wide-bandgap ultraviolet sensors such as GaN, AlGaN, and SiC. Iron oxides contain significantly less iron than pure iron; therefore, the responsivity of wide-bandgap ultraviolet sensors to plasma radiation generated by laser vaporization of pure iron is significantly greater than their responsivity to plasma radiation generated by laser vaporization of rust (iron oxides). Based on this principle, this invention can use the relative magnitude of the photoelectric response value of the wide-bandgap ultraviolet sensor to determine whether laser rust removal has reached an over-ablation state.

[0047] The present invention employs the aforementioned rust removal device for a low-power adaptive curved surface laser rust removal method, specifically including the following steps:

[0048] Step 1: The binocular camera 13 captures an RGB image of the surface of the workpiece 31 to be rusted. Based on the RGB image, the microcontroller 2 uses a binocular stereo vision matching (SGBM) algorithm to construct a three-dimensional shape model of the workpiece 31, which is the depth information f(x,y,z) of the distance from the laser 11's output port to the three-dimensional surface of the workpiece 31. Based on the RGB image, the microcontroller 2 uses a color block hue-saturation-value (HSV) recognition algorithm to obtain an HSV array, a binarization algorithm to obtain a binary array, and a target segmentation algorithm to obtain the boundary position information s(x,y) of each rust area 32 and the total number K of rust areas 32.

[0049] Step 2: Define a square area with side length L as a scanning unit. Divide each rust area into scanning units, that is, take the minimum x-coordinate, maximum x-coordinate, minimum y-coordinate, and maximum y-coordinate of the boundary position information s(x, y) of the rust area as the four vertices to construct a rectangular area (i.e., the area to be derusted). Starting from the upper left corner of the rectangular area, divide this rectangular area into N rows and M columns of scanning unit grids. Microcontroller 2 controls the x and y axes of the three-dimensional electric displacement stage 1, aligning the light output port of laser 11 with the center position of the first row and first column of the first rust area scanning unit. According to the depth information f(x, y, z), control the z axis of the three-dimensional electric displacement stage 1 so that the initial value W0 of the distance between the light output port of laser 11 and the rust area 32 is:

[0050] W0=μF0 (1)

[0051] Where μ is a constant coefficient ranging from 1.1 to 1.5, and F0 is the room-temperature focal length of the laser lens group 11. G is defined as follows. th Z is the over-ablation ultraviolet radiation threshold. max Let Z be the z-axis coordinate value of the under-burning boundary line 42 of the defocusing amount. max The initial value is Z0:

[0052] Z0=(μ-1)F0 (2)

[0053] The counter variable 'a' representing the rust zone sequence number is initialized to 1, the counter variable 'i' representing the rust zone scan unit grid row number is initialized to 1, and the counter variable 'j' representing the rust zone scan unit grid column number is initialized to 2.

[0054] Step 3: Based on the two-dimensional galvanometer inside the laser 11, the laser beam 12 scans a square area with a side length of L on the workpiece 31 to be derusted point by point (i.e., the light covers a scanning unit for derusting). During this process, a wide-bandgap ultraviolet sensor 14 continuously collects the ultraviolet component in the plasma radiation. After digital-to-analog conversion and summation, the total ultraviolet radiation G corresponding to the scanning unit is obtained. One of the cameras in the binocular camera 13 takes a picture of the workpiece 31 to be derusted to obtain an RGB image. Based on the HSV algorithm and binarization algorithm, a binary array of the current scanning unit is obtained, that is, the image of the current scanning unit is transformed into only white pixels (representing the cleaned rust sites) and black pixels (representing the uncleaned rust sites). The derusting rate η is defined as the number of white pixels divided by the total number of pixels in the scanning unit. The derusting rate η and the derusting rate threshold η are detected and compared. th If η>=η th This is considered as the rust removal of this scanning unit being completed. The G value at this point is recorded, thus obtaining G. th The value is:

[0055] G th=αG (3)

[0056] In the formula, α is a constant coefficient ranging from 2 to 10. Proceed to step 4. If η < η th This is considered as under-ablation in this scanning unit. The laser 11 on the z-axis of the three-dimensional electric displacement stage 1 moves closer to the workpiece 31 to be derusted by a step size D. z To obtain a higher laser spot power density, Z is assigned a value. max =Z max -D z Proceed to step 3.

[0057] Step 4: If j <= M, then the microcontroller 2 controls the electric displacement stage 1 to move along the x and y axes, so that the light output port of the laser 11 is aligned with the center position of the scanning unit in the i-th row and j-th column of the a-th rust area, and then executes step 5. If j > M, then the assignment statement j = 1 and i = i + 1 is executed, and then step 7 is executed.

[0058] Step 5: Control the z-axis of the three-dimensional electric displacement stage 1 according to the depth information f(x, y, z), so that the distance W between the light output port of the laser 11 and the rust area 32 is:

[0059] W = F0 + Z max (4)

[0060] The laser 11 is used to remove rust from the current scanning unit. During this process, a wide-bandgap ultraviolet sensor 14 continuously collects the ultraviolet component in the plasma radiation. After digital-to-analog conversion and summation, the total ultraviolet radiation G corresponding to the scanning unit is obtained. One of the cameras in the binocular camera 13 is used to take a picture of the workpiece 31 to be removed to obtain an RGB image. The rust removal rate η is obtained based on the HSV algorithm and the binarization algorithm. η and η' are compared. th If η>=η th This means that the rust removal in this scanning unit was successful. The assignment statement j = j + 1 is executed, and step 6 is followed. If η < η th This means an under-ablation state. In order for the laser 11 to move closer to the workpiece 31 to be derusted by a step size D, z The assignment statement Z is executed. max =Z max -D z To obtain a higher laser spot power density, step 5 is then performed.

[0061] Step 6, compare G and G th If G > G th This means an over-ablation state. In order for the laser 11 to move away from the workpiece 31 to be removed by a step size D, z The assignment statement Z is executed. max =Z max +Dz To obtain a lower laser spot power density, step 7 is then performed. If G <= G th Then proceed to step 7.

[0062] Step 7: If i <= N, then execute step 4; if i > N, then execute the amplitude statement i = 1 and a = a + 1, and then execute step 8.

[0063] Step 8: If a <= K, then proceed to step 4; if a > K, it means that all rusted areas have been removed and the program ends.

[0064] Example:

[0065] A GSS-FIB-20 laser was selected, with a wavelength of 1064nm, a pulse width of 100ns, a beam quality M² < 2, a minimum linewidth of 0.01mm, and a focal length F₀ of 18cm for the laser focusing lens. The average power of the laser was set to 20W, and the repetition rate to 20kHz. An LTK-G3535SGH photodiode was selected as the wide-bandgap ultraviolet sensor, with a response spectrum range as shown below. Figure 3 As shown. The camera used is a WX605 high-speed industrial camera, the microcontroller is an STM32F407ZGT6, and the workpiece to be derusted is a rusty iron block with an outer surface curvature of approximately 0.385.

[0066] Set F0=18cm, μ=1.2, α=3, η th =98%, D z =400μm, L=0.5cm. First, a microprocessor controls a binocular camera to photograph the workpiece surface, based on... Figure 6 The algorithm shown obtains the three-dimensional morphological information f(x, y, z) of the workpiece and identifies the location of the rust area s(x, y). Each rust area is processed sequentially, and each rust area is divided into several square scanning units with a side length of L. After each scanning unit is ablated by a laser, the left camera of the binocular camera is controlled by a microprocessor to take a picture of the workpiece once. Figure 6 The algorithm shown obtains the HSV array of the scanning unit, uses (10, 40, 50) as a binarization threshold to perform binarization processing on the HSV array, obtains a binary array, and calculates the current rust removal rate η of the scanning unit. If the rust removal rate is qualified (η>=η), th If the rust removal rate is not up to standard, it means under-ablation, and the laser power density needs to be increased. Therefore, the translation stage is moved along the z-axis to bring the laser closer to the workpiece by a step size D. zThen, the current scanning unit is derusted again, and this process is repeated until the rust removal rate of the current scanning unit is qualified. During each rust removal scan, a wide-bandgap ultraviolet sensor continuously collects the ultraviolet component in the plasma radiation. The microcontroller performs digital-to-analog conversion and accumulation calculation to obtain the total ultraviolet radiation G corresponding to the square scanning unit. At the end of each scanning unit's rust removal, it is determined whether the total ultraviolet radiation G of this scanning unit is greater than the over-ablation ultraviolet threshold G. th If the value is greater than 1, it means that over-ablation has occurred in that scanning unit, and the spot power density needs to be reduced in the next scanning unit. Therefore, the translation stage is moved along the z-axis to move the laser away from the workpiece by one step D. z .

[0067] Comparing the rusted areas before and after processing, the effect is as follows: Figure 7 As shown, rust can be completely removed without excessive cutting and wear on the iron surface.

Claims

1. A method for rust removal using a low-power adaptive curved surface laser rust removal device, characterized in that: The low-power adaptive curved surface laser rust removal device includes a three-dimensional electric displacement stage (1), a laser (11) is installed on the three-dimensional electric displacement stage (1), and a wide bandgap ultraviolet sensor (14) and a binocular camera (13) are respectively provided on one side of the laser (11) from top to bottom. The three-dimensional electric displacement stage (1) is connected to a microcontroller (2). Specifically, the steps include the following: Step 1: Obtain an image of the rust area (32) of the workpiece (31) to be derusted; Step 2: Construct the scanning area based on the image obtained in Step 1; Step 3: Perform rust removal treatment within the scanned area constructed in Step 2; First, a microprocessor-controlled binocular camera is used to photograph the workpiece surface, obtaining its three-dimensional morphology information and identifying the location of rust areas. Each rust area is then processed sequentially, divided into several scanning units. After each scanning unit is ablated by the laser, the left camera in the binocular camera is controlled by the microprocessor to photograph the workpiece once, obtaining a binary array. The current rust removal rate of that scanning unit is calculated. If the rust removal rate is acceptable, the laser is moved to the next scanning unit. If the rust removal rate is unacceptable, indicating under-ablation, the laser power density needs to be increased. Therefore, the translation stage is moved along the z-axis to bring the laser closer to the workpiece by a step size D. z Then, the current scanning unit is derusted again, and this process is repeated until the rust removal rate of the current scanning unit is qualified. During each rust removal scan, a wide-bandgap ultraviolet sensor continuously collects the ultraviolet component of the plasma radiation. The microcontroller performs digital-to-analog conversion and summation to obtain the total ultraviolet radiation G corresponding to that scan unit. At the end of each scan unit, it is determined whether the total ultraviolet radiation G of that scan unit is greater than the over-ablation ultraviolet threshold G. th If the value is greater than 1, it means that over-ablation has occurred in that scanning unit, and the spot power density needs to be reduced in the next scanning unit. Therefore, the translation stage is moved along the z-axis to move the laser away from the workpiece by one step D. z .

2. The low-power adaptive curved surface laser rust removal method according to claim 1, characterized in that: The specific process of step 1 is as follows: Step 1.1: Take an RGB image of the workpiece (31) to be rusted by capturing the surface of the workpiece (31) to be rusted by using a binocular camera (13); Step 1.2, the microcontroller (2) constructs a three-dimensional shape model of the workpiece (31) to be rusted using the binocular stereo vision matching SGBM algorithm based on the RGB image of the workpiece (31) to be rusted, which is the depth information f(x,y,z) of the distance between the light outlet of the laser (11) and the three-dimensional surface of the workpiece (31) to be rusted. Step 1.3, the microcontroller (2) obtains an HSV array based on the RGB image of the workpiece (31) to be derusted using a color block hue-saturation-brightness recognition algorithm, obtains a binary array using a binarization algorithm, and performs target segmentation to obtain the boundary position information s(x,y) of each rust area (32) and the total number K of rust areas (32).

3. The low-power adaptive curved surface laser rust removal method according to claim 2, characterized in that: The specific process of step 2 is as follows: Step 2.1: Define a square area with side length L as a scanning unit. Divide each rust area into scanning units, that is, take the minimum x coordinate, maximum x coordinate, minimum y coordinate, and maximum y coordinate of the boundary position information s(x,y) of the rust area as the four vertices, construct a rectangular rust removal area, and start from the upper left corner of the rust removal area to divide the area into N rows and M columns of scanning unit grids. Step 2.2: The microcontroller (2) controls the x and y axes of the three-dimensional electric displacement stage (1) to align the laser (11) output port with the center position of the first row and first column scanning unit of the first rust zone. Based on the depth information f(x,y,z), the microcontroller controls the z axis of the three-dimensional electric displacement stage 1 so that the initial value W0 of the distance between the laser (11) output port and the rust zone 32 is: W0=µF0(1) Where µ is a constant coefficient and F0 is the room temperature focal length of the laser lens group; Step 2.3, Define G th Z is defined as the over-ablation ultraviolet radiation threshold. max Let Z be the z-axis coordinate value of the under-burning boundary line (42) of the defocusing amount. max The initial value is Z0. The counter variable a, which represents the rust zone sequence number, is initialized to 1. The counter variable i, which represents the rust zone scan unit grid row number, is initialized to 1. The counter variable j, which represents the rust zone scan unit grid column number, is initialized to 2. Z0 = (µ-1)F0(2) Where µ is a constant coefficient and F0 is the room temperature focal length of the laser lens group.

4. The low-power adaptive curved surface laser rust removal method according to claim 3, characterized in that: The specific process of step 3 is as follows: Step 3.1: Based on the two-dimensional galvanometer inside the laser (11), the laser beam (12) scans a square scanning unit with a side length of L on the workpiece (31) to be rusted point by point to remove rust. During this process, a wide bandgap ultraviolet sensor continuously collects the ultraviolet component in the plasma radiation and records the total ultraviolet radiation G corresponding to the scanning unit. Step 3.2: Use one of the cameras in the binocular camera (13) to take a picture of the workpiece (31) to be derusted to obtain an RGB image. Based on the HSV algorithm and the binarization algorithm, obtain the binary array of the current scanning unit, that is, the image of the current scanning unit is transformed into only white pixels that have been derusted and black pixels that have not been derusted. Define the derusting rate η as the number of white pixels divided by the total number of pixels in the scanning unit. Detect and compare the derusting rate η and the derusting rate threshold η. th If η>=η th Then it is considered that the rust removal of this scanning unit is completed, and the G value at this time is recorded. Then the over-ablation ultraviolet radiation threshold G is obtained according to the following formula (3). th If the value is less than η, then proceed to step 3.

3. th This is considered as under-ablation in this scanning unit, and the laser on the z-axis of the three-dimensional electric displacement stage moves closer to the workpiece to be removed by a step size D. z Assign Z max =Z max -D z Repeat step 3.1; G th =αG(3) In the formula, α is a constant coefficient; Step 3.3: If j <= M, the microcontroller (2) controls the three-dimensional electric displacement stage (1) to move the laser (11) so that the laser (11) output port is aligned with the center position of the scanning unit in the i-th row and j-th column of the a-th rust area, and then executes step 3.4; if j > M, the assignment statement j = 1 and i = i + 1 is executed, and then step 3.6 is executed. Step 3.4: Control the z-axis of the three-dimensional electric displacement stage (1) according to the depth information f(x, y, z) so that the distance between the light outlet of the laser (11) and the rust area (32) is W. Based on the laser (11), rust removal is performed on the current scanning unit. During this process, the ultraviolet component in the plasma radiation is continuously collected by the wide bandgap ultraviolet sensor (14) to obtain the total ultraviolet radiation G corresponding to the scanning unit. One of the cameras in the binocular camera (13) is used to take pictures of the workpiece (31) to be rusted to obtain an RGB image. The rust removal rate η and η at this time are then used to determine the rust removal rate. th For comparison, if η>=η th If η < η, it means that the rust removal in this scanning unit was successful. The assignment statement j = j + 1 is executed, and step 3.5 is followed. th This means an under-ablation state. In order for the laser (11) to move closer to the workpiece (31) to be derusted by a step size D, z The assignment statement Z is executed. max =Z max -D z and W = F0 + Z max Repeat step 3.4; Step 3.5, compare G and G th If G > G th This means an over-ablation state. In order for the laser (11) to move away from the workpiece (31) to be derusted by a step size D, z The assignment statement Z is executed. max =Z max +D z Then proceed to step 3.6; if G <= G th Then proceed directly to step 3.6; Step 3.6: If i <= N, then execute step 3.3; if i > N, then execute the amplitude statement i = 1 and a = a + 1, and then execute step 3.

7. Step 3.7: If a <= K, then proceed to step 3.3; if a > K, it means that all rusted areas have been derusted and the derusting process is complete.

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