Method for eliminating electrostatic spray gun motion compensation for spraying the front and back of aluminum products

Abstract

The application is suitable for the technical field of aluminum material spraying control, and particularly relates to a static spray gun motion compensation method for eliminating positive and negative surfaces of aluminum material spraying. The static spray gun motion compensation method for eliminating positive and negative surfaces of aluminum material spraying comprises the following steps: obtaining aluminum material surface structure information; determining a first type region and a second type region based on the aluminum material surface structure information; generating a first spraying parameter based on the first type region and a second spraying parameter based on the second type region; generating a parameter mutation feature based on the first spraying parameter and the second spraying parameter; when the spray gun moves from the first type region to the second type region, generating a spray gun motion compensation track based on the parameter mutation feature, adjusting the first spraying parameter to the second spraying parameter by the spray gun, and moving the spray gun from the first type region to the second type region along the spray gun motion compensation track. The method effectively reduces the coating deposition deviation caused by parameter mutation and the motion and parameter adjustment asynchronization problem, and significantly improves the positive and negative surface phenomenon.

Description

Technical Field

[0001] This application belongs to the field of aluminum spraying control technology, and in particular relates to a method for compensating the motion of an electrostatic spray gun to eliminate uneven spraying surfaces on aluminum materials. Background Technology

[0002] Aluminum, with its excellent properties such as light weight, corrosion resistance, and ease of processing, is widely used in many fields, including building decoration, transportation, electronic equipment, and aerospace. In the processing and manufacturing of aluminum, spraying is one of the key processes for improving its appearance quality, protective performance, and extending its service life. Among these processes, electrostatic spraying technology has become the mainstream technology for aluminum spraying due to its advantages such as high paint utilization, good coating uniformity, and high construction efficiency. The basic principle of electrostatic spraying is to charge paint particles with an electrostatic spray gun. Under the action of a high-voltage electrostatic field, the paint particles move towards and deposit on the grounded aluminum workpiece surface, forming a continuous and uniform coating. However, in actual production, when the surface of the aluminum workpiece has planar surfaces and complex geometric areas, uneven coating thickness, often referred to as "uneven sides," can easily occur. This severely affects the appearance quality of the product, and may even lead to defective products, increasing production costs.

[0003] In existing technologies, to improve the consistency of coating thickness in flat and complex geometric areas of aluminum workpieces, different spraying parameters are used to apply targeted spraying to different surface structures. However, this still results in uneven coating surfaces when adjusting the spraying parameters. Summary of the Invention

[0004] This application provides a method for compensating the motion of an electrostatic spray gun to eliminate uneven surfaces in aluminum spraying. This method can solve the problem of uneven surfaces that occur when different spraying parameters are used to spray different surface structures.

[0005] In a first aspect, embodiments of this application provide a method for compensating the motion of an electrostatic spray gun to eliminate uneven surfaces during aluminum spraying, including:

[0006] Obtain information on the surface structure of aluminum materials;

[0007] Based on the surface structure information of the aluminum material, a first type of region and a second type of region are determined; wherein, the first type of region is used to indicate a region where the aluminum material structure is planar, and the second type of region is used to indicate a region where the aluminum material structure is complex geometry, and the first type of region and the second type of region are adjacent to each other;

[0008] First spraying parameters are generated based on the first type of region, and second spraying parameters are generated based on the second type of region;

[0009] A parameter mutation feature is generated based on the first spraying parameter and the second spraying parameter; wherein, the parameter mutation feature is used to reflect the changes in the spraying parameters of the spray gun;

[0010] When the spray gun is detected moving from the first type of area to the second type of area, a spray gun motion compensation trajectory is generated based on the parameter change characteristics, and the spray gun is controlled to adjust the first spraying parameters to the second spraying parameters, while moving from the first type of area to the second type of area according to the spray gun motion compensation trajectory.

[0011] The technical solutions described in this application embodiment have at least the following technical effects:

[0012] The electrostatic spray gun motion compensation method for eliminating uneven spraying of aluminum materials provided in this application involves: acquiring surface structure information of the aluminum material; then determining a first type of region indicating a planar aluminum structure and a second type of region indicating a complex geometric aluminum structure adjacent to the first type of region based on the surface structure information; generating first spraying parameters based on the first type of region and second spraying parameters based on the second type of region; generating parameter mutation features reflecting changes in the spray gun's spraying parameters based on the first and second spraying parameters; and generating a spray gun motion compensation trajectory based on the parameter mutation features when the spray gun is detected moving from the first type of region to the second type of region, controlling the spray gun to adjust the first spraying parameters to the second spraying parameters, and simultaneously moving from the first type of region to the second type of region using the spray gun motion compensation trajectory. This method accurately acquires the surface structure information of aluminum materials to clearly define the planar and complex geometric adjacent areas, generates targeted spraying parameters for different areas to adapt to the electrostatic field distribution characteristics caused by structural differences, and then achieves synchronous and smooth adjustment of spraying parameters and motion trajectory when the spray gun moves across areas by extracting parameter mutation features and generating motion compensation trajectories. This effectively reduces the coating deposition deviation caused by parameter mutation and the problem of asynchronous movement and parameter adjustment, significantly improves the phenomenon of uneven coating, and enhances the coating uniformity and product appearance quality. At the same time, it is also applicable to scenarios where there are large differences in spraying parameters between areas, and can spray two different areas separately without starting and stopping the electrostatic spray gun, thus improving spraying efficiency.

[0013] Secondly, embodiments of this application provide an electrostatic spray gun motion compensation system for eliminating uneven spraying on aluminum materials, comprising:

[0014] The acquisition module is used to acquire surface structure information of aluminum materials;

[0015] The determination module is used to determine a first type of region and a second type of region based on the surface structure information of the aluminum material; wherein, the first type of region is used to indicate a region where the aluminum material structure is planar, and the second type of region is used to indicate a region where the aluminum material structure is complex geometry, and the first type of region and the second type of region are adjacent to each other;

[0016] The first generation module is used to generate first spraying parameters based on the first type of region and second spraying parameters based on the second type of region;

[0017] The second generation module is used to generate parameter mutation features based on the first spraying parameters and the second spraying parameters; wherein, the parameter mutation features are used to reflect the changes in the spraying parameters of the spray gun;

[0018] The third generation module is used to detect when the spray gun moves from the first type of area to the second type of area, generate a spray gun motion compensation trajectory based on the parameter change characteristics, and control the spray gun to adjust the first spraying parameters to the second spraying parameters, while moving from the first type of area to the second type of area according to the spray gun motion compensation trajectory.

[0019] Thirdly, embodiments of this application provide an electrostatic spray gun motion compensation device for eliminating uneven surfaces in aluminum spraying, including a spraying device and a control device. The control device is electrically connected to the spraying device. The control device includes a memory, a processor, and a computer program stored in the memory and executable on the processor. When the processor executes the computer program, it implements the method described in any one of the first aspects above.

[0020] Fourthly, embodiments of this application provide a computer-readable storage medium storing a computer program that, when executed by a processor, implements the method described in any one of the first aspects above.

[0021] Fifthly, embodiments of this application provide a computer program product that, when running on an electrostatic spray gun motion compensation device for eliminating uneven surfaces in aluminum spraying, causes the electrostatic spray gun motion compensation device for eliminating uneven surfaces in aluminum spraying to execute the electrostatic spray gun motion compensation method for eliminating uneven surfaces in aluminum spraying as described in any of the first aspects.

[0022] It is understood that the beneficial effects of the second to fifth aspects mentioned above can be found in the relevant descriptions in the first aspect mentioned above, and will not be repeated here. Attached Figure Description

[0023] To more clearly illustrate the technical solutions in the embodiments of this application, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0024] Figure 1 This is a flowchart illustrating the electrostatic spray gun motion compensation method for eliminating uneven surfaces in aluminum spraying provided in this application embodiment.

[0025] Figure 2 This is a schematic diagram illustrating the implementation process of the electrostatic spray gun motion compensation method for eliminating the uneven surface of aluminum spraying provided in the embodiments of this application;

[0026] Figure 3 This is a schematic diagram of the electrostatic spray gun motion compensation system for eliminating uneven surfaces in aluminum spraying, provided in an embodiment of this application.

[0027] Figure 4 This is a schematic diagram of the control device for the electrostatic spray gun motion compensation equipment that eliminates the unevenness of aluminum spraying surfaces, as provided in the embodiments of this application. Detailed Implementation

[0028] In the following description, specific details such as particular system architectures and techniques are set forth for illustrative purposes and not for limitation, in order to provide a thorough understanding of the embodiments of this application. However, those skilled in the art will understand that this application may also be implemented in other embodiments without these specific details. In other instances, detailed descriptions of well-known systems, apparatuses, circuits, and methods have been omitted so as not to obscure the description of this application with unnecessary detail.

[0029] It should be understood that, when used in this application specification and the appended claims, the term "comprising" indicates the presence of the described features, integrals, steps, operations, elements and / or components, but does not exclude the presence or addition of one or more other features, integrals, steps, operations, elements, components and / or a collection thereof.

[0030] It should also be understood that the term “and / or” as used in this application specification and the appended claims means any combination of one or more of the associated listed items and all possible combinations, and includes such combinations.

[0031] As used in this application specification and the appended claims, the term "if" may be interpreted, depending on the context, as "when," "once," "in response to determination," or "in response to detection." Similarly, the phrase "if determination" or "if the described condition or event is detected" may be interpreted, depending on the context, as "once determination," "in response to determination," "once the described condition or event is detected," or "in response to the detection of the described condition or event."

[0032] Furthermore, in the description of this application and the appended claims, the terms "first," "second," "third," etc., are used only to distinguish descriptions and should not be construed as indicating or implying relative importance.

[0033] References to "one embodiment" or "some embodiments" as described in this specification mean that one or more embodiments of this application include a specific feature, structure, or characteristic described in connection with that embodiment. Therefore, the phrases "in one embodiment," "in some embodiments," "in other embodiments," "in still other embodiments," etc., appearing in different parts of this specification do not necessarily refer to the same embodiment, but rather mean "one or more, but not all, embodiments," unless otherwise specifically emphasized. The terms "comprising," "including," "having," and variations thereof mean "including but not limited to," unless otherwise specifically emphasized.

[0034] Aluminum, with its excellent properties such as light weight, corrosion resistance, and ease of processing, is widely used in many fields, including building decoration, transportation, electronic equipment, and aerospace. In the processing and manufacturing of aluminum, spraying is one of the key processes for improving its appearance quality, protective performance, and extending its service life. Among these processes, electrostatic spraying technology has become the mainstream technology for aluminum spraying due to its advantages such as high paint utilization, good coating uniformity, and high construction efficiency. The basic principle of electrostatic spraying is to charge paint particles with an electrostatic spray gun. Under the action of a high-voltage electrostatic field, the paint particles move towards and deposit on the grounded aluminum workpiece surface, forming a continuous and uniform coating. However, in actual production, when the surface of the aluminum workpiece has planar surfaces and complex geometric areas, uneven coating thickness, often referred to as "uneven sides," can easily occur. This severely affects the appearance quality of the product, and may even lead to defective products, increasing production costs.

[0035] In existing technologies, to improve the consistency of coating thickness in flat and complex geometric areas of aluminum workpieces, different spraying parameters are used to apply targeted spraying to different surface structures. However, this still results in uneven coating surfaces when adjusting the spraying parameters.

[0036] To address the aforementioned issues, this application provides a method for electrostatic spray gun motion compensation to eliminate uneven coating on aluminum materials. This method involves acquiring aluminum surface structure information; then, based on this information, determining a first type of region indicating a planar aluminum structure and a second type of region indicating a complex geometric aluminum structure adjacent to the first type of region; generating first spraying parameters based on the first type of region and second spraying parameters based on the second type of region; generating parameter abrupt change features reflecting changes in spray gun parameters based on the first and second spraying parameters; and detecting a movement of the spray gun from the first type of region to the second type of region, generating a spray gun motion compensation trajectory based on the parameter abrupt change features, and controlling the spray gun to adjust the first spraying parameters to the second spraying parameters while simultaneously moving from the first type of region to the second type of region using the spray gun motion compensation trajectory. This method accurately acquires the surface structure information of aluminum materials to clearly define the planar and complex geometric adjacent areas, generates targeted spraying parameters for different areas to adapt to the electrostatic field distribution characteristics caused by structural differences, and then achieves synchronous and smooth adjustment of spraying parameters and motion trajectory when the spray gun moves across areas by extracting parameter mutation features and generating motion compensation trajectories. This effectively reduces the coating deposition deviation caused by parameter mutation and the problem of asynchronous movement and parameter adjustment, significantly improves the phenomenon of uneven coating, and enhances the coating uniformity and product appearance quality. At the same time, it is also applicable to scenarios where there are large differences in spraying parameters between areas, and can spray two different areas separately without starting and stopping the electrostatic spray gun, thus improving spraying efficiency.

[0037] The electrostatic spray gun motion compensation method for eliminating uneven surfaces in aluminum spraying provided in this application embodiment can be applied to an electrostatic spray gun motion compensation device for eliminating uneven surfaces in aluminum spraying. In this case, the electrostatic spray gun motion compensation device for eliminating uneven surfaces in aluminum spraying is the executing subject of the electrostatic spray gun motion compensation method for eliminating uneven surfaces in aluminum spraying provided in this application embodiment. This application embodiment does not impose any restrictions on the specific type of electrostatic spray gun motion compensation device for eliminating uneven surfaces in aluminum spraying.

[0038] For example, an electrostatic spray gun motion compensation device for eliminating uneven coating on aluminum materials can include a spraying device and a control device, with the control device electrically connected to the spraying device. The spraying device is used to spray the aluminum material. The spraying device includes an electrostatic spray gun, a motion actuator, and a paint supply unit. The electrostatic spray gun charges and sprays paint particles, and is equipped with a flow regulating valve, an atomizer, and a distance sensor, used to adjust the spray flow rate, control the paint atomization effect, and detect the real-time distance between the spray gun and the aluminum surface, respectively. The motion actuator is connected to the electrostatic spray gun and can drive the electrostatic spray gun to move along a preset or compensated trajectory. It includes a multi-axis robotic arm and a drive motor, possessing high-precision positioning and speed adjustment capabilities. The paint supply unit is connected to the electrostatic spray gun and continuously provides it with paint at a stable pressure, including a paint storage tank, a booster pump, and a filter. The control device monitors and controls the entire spraying process.

[0039] For example, the control device can be a PLC, microcontroller, mobile phone, tablet computer, wearable device, augmented reality (AR) / virtual reality (VR) device, laptop computer, ultra-mobile personal computer (UMPC), netbook, personal digital assistant (PDA), desktop computer, smart screen, smart TV and other terminal devices, computing devices or other processing devices connected to a wireless modem, IoT terminal, computer, customer premises equipment (CPE) and / or other devices for communication over a wireless system, as well as next-generation communication systems, such as mobile terminals in 5G networks or mobile terminals in future evolved Public Land Mobile Networks (PLMNs).

[0040] To better understand the electrostatic spray gun motion compensation method for eliminating uneven surfaces in aluminum spraying provided in this application embodiment, the specific implementation process of the electrostatic spray gun motion compensation method for eliminating uneven surfaces in aluminum spraying provided in this application embodiment will be described by way of example below.

[0041] Figure 1 and Figure 2 A schematic flowchart of the electrostatic spray gun motion compensation method for eliminating uneven surfaces in aluminum spraying, as provided in an embodiment of this application, is shown. The electrostatic spray gun motion compensation method for eliminating uneven surfaces in aluminum spraying includes:

[0042] S100, obtains surface structure information of aluminum materials.

[0043] For example, aluminum surface structure information can be obtained from an aluminum database, or through a camera or other imaging equipment, etc., but is not limited to these methods. An aluminum database refers to a database containing the surface structures of all types of aluminum. This data can be obtained through laboratory experiments, on-site measurements and monitoring, and past experience. After acquisition, the collected data is organized, classified, and archived, useful information and patterns are extracted, and the relevant data is then saved into the database to form an aluminum database.

[0044] S200, Based on the surface structure information of aluminum material, a first type of region and a second type of region are determined; wherein, the first type of region is used to indicate the region where the aluminum material structure is planar, and the second type of region is used to indicate the region where the aluminum material structure is complex geometry, and the first type of region and the second type of region are adjacent.

[0045] It can be understood that all structures in the first category are continuous planar structures, while the second category consists of partial planar structures and complex geometric structures. For example, when there is a groove in the aluminum material, the second category includes the groove area and the partially planar area adjacent to the groove. Exemplarily, the first and second categories can be determined by establishing region classification rules. For the second category (complex geometric regions), the determination can cover various geometric shapes, including but not limited to: grooves (depth ≥ 0.5mm, width ≤ 5mm), protrusions (height ≥ 0.5mm, diameter ≤ 10mm), arc transitions (radius of curvature ≤ 20mm), corners (angle ≤ 120°), etc. Through geometric feature recognition algorithms, such as curvature analysis of surface point cloud data, regions with curvature values ​​≥ a preset curvature threshold are initially determined as complex regions; then, combined with region connectivity analysis, adjacent complex geometric features (such as grooves and adjacent corners) are integrated into a continuous second category region. The remaining regions can be classified as first category regions. Alternatively, the first type of area can be judged first. The judgment criteria are: the height difference between any two points on the surface is ≤ the preset flatness threshold (set according to the product accuracy requirements, such as 0.05mm), and the continuous plane area is ≥ the minimum plane area threshold (such as 10cm). 2 By traversing the surface structure information of aluminum materials to extract the three-dimensional coordinate data of the surface, the height variance within the neighborhood of each data point is calculated. If the variance is less than or equal to the threshold and the area of ​​the continuous region meets the standard, it can be marked as a planar region. Other regions can be classified as the second type of region.

[0046] S300 generates first spraying parameters based on the first type of region and second spraying parameters based on the second type of region.

[0047] This step is understandably crucial for achieving differentiated spraying. It requires generating suitable spraying parameters based on the geometric differences between the two types of regions and the electrostatic spraying process mechanism. Core parameters include spraying flow rate, spraying range (atomization angle), distance between the spray gun and the workpiece, and electrostatic voltage. For example, the first and second types of regions can be matched separately in an aluminum material database to obtain corresponding first and second spraying parameters; alternatively, the first and second types of regions can be input into a learning model, which outputs the corresponding first and second spraying parameters, and so on, but is not limited to these methods. The learning model is trained using multiple sets of training data, each set including the region structure and size of the aluminum material and the corresponding spraying parameters.

[0048] S400, generates parameter mutation features based on the first spraying parameters and the second spraying parameters; wherein, the parameter mutation features are used to reflect the changes in the spraying parameters of the spray gun.

[0049] It is understandable that the generation of parameter mutation features can be quantitatively output through algorithms and stored in the form of feature vectors. For example, parameter mutation features could be [flow mutation amplitude 15% (decreasing), range mutation amplitude 30% (shrinking), distance mutation amplitude 25% (shortening), correlation degree 90% (strong correlation), etc.].

[0050] S500, when the spray gun is detected moving from the first type of area to the second type of area, a spray gun motion compensation trajectory is generated based on the parameter change characteristics, and the spray gun is controlled to adjust the first spraying parameter to the second spraying parameter, while moving from the first type of area to the second type of area using the spray gun motion compensation trajectory.

[0051] It is understandable that when the spray gun finishes spraying the first type of area and begins to move from the first type of area to the second type of area, the spray gun adjusts the spray flow rate from the first spray parameter to the second spray parameter.

[0052] For example, the transition region from the first type of region to the second type of region can be determined by parameter mutation features. Then, based on this transition region and the parameter mutation features, the distance and corresponding speed between the spray gun and the transition region can be generated, i.e., the spray gun motion compensation trajectory. Alternatively, the parameter mutation features can be input into the learning model, and the learning model can output the corresponding spray gun motion compensation trajectory, and so on, but are not limited to these.

[0053] In one possible implementation, step S500 involves generating a spray gun motion compensation trajectory based on parameter abrupt change characteristics, including:

[0054] S510, based on parameter mutation characteristics, determines the sensitive area; whereby the sensitive area is used to reflect the area where the spray gun is likely to form a yin-yang surface after moving from the first type of area to the second type of area.

[0055] It is understandable that when the spray gun moves from the first type of region (planar) to the second type of region (complex geometry) and switches from the first spraying parameter to the second spraying parameter, the parameter abrupt change directly disrupts the deposition balance of paint particles, forming a risk zone (the initial form of a sensitive area) due to deposition imbalance. For example, spray range abrupt change features and spray flow rate abrupt change features can be extracted based on parameter abrupt change features. Then, the initial sensitive zone region can be determined based on the spray range abrupt change features, and the initial sensitive zone region can be adjusted based on the spray flow rate abrupt change features to obtain the sensitive area. Alternatively, the parameter abrupt change features can be input into a learning model, and the learning model can output the corresponding sensitive area.

[0056] In one possible implementation, step S510, determining the sensitive region based on parameter mutation characteristics, includes:

[0057] S511, based on parameter mutation features, extract the spraying range mutation features and spraying flow rate mutation features; among them, the spraying range mutation features are used to reflect the changes in the coating particles sprayed from the spray gun covering the aluminum surface, and the spraying flow rate mutation features are used to reflect the density changes of the coating particles sprayed from the spray gun.

[0058] This step is understandable as a crucial step in deconstructing the core influencing factors from the "overall parameter mutation characteristics." Essentially, it focuses on the two parameters that most directly affect the "coverage range" and "particle density" of coating deposition. Through feature extraction, it transforms "abstract parameter differences" into "concrete influence dimensions," providing precise quantitative basis for subsequent sensitive area delineation. For the mutation characteristics of the spraying range, the core is to quantify the "change in the coating particle coverage radius"; for the mutation characteristics of the spraying flow rate, the core is to quantify the "change in the number of coating particles and deposition density per unit time."

[0059] S512, the initial sensitive zone region is determined based on the abrupt change characteristics of the spraying range.

[0060] This step is understandably the core step in constructing the "sensitive area basic framework" based on the abrupt changes in the spraying range. Essentially, it transforms the "coverage imbalance risk" caused by range abrupt changes into a concrete spatial geometric region (initial sensitive zone). For example, after determining the boundary lines of the first and second types of regions, the coverage area of ​​the spraying range can be determined based on the abrupt changes in the spraying range characteristics. Then, the boundaries of the coverage area of ​​the spraying range can be adjusted according to these characteristics to obtain the initial sensitive zone region.

[0061] A quantitative mapping relationship between the characteristics of abrupt changes in the spraying range and the risk range can also be established. First, extract the core parameters from the characteristics of abrupt changes in the spraying range: including the spraying range angle α1 of the first type of area, the spraying range angle α2 of the second type of area, and the reference distance d between the spray gun and the aluminum surface (d1 for the first type of area and d2 for the second type of area). Calculate the actual spraying coverage radius of the two types of areas using geometric formulas [r1=d1×tan(α1 / 2), r2=d2×tan(α2 / 2)]. Then calculate the difference in coverage radius abrupt change Δr=|r1-r2|—this difference directly determines the lateral range of the coverage imbalance risk. For example, if α1 = 90° and d1 = 250mm, then r1 = 250 × tan45° = 250mm; α2 = 45° and d2 = 200mm, then r2 = 200 × tan22.5° ≈ 82.8mm, Δr = 167.2mm. This means that there is a 167.2mm risk of "coverage discontinuity" or "overlap" at the transition between the two types of areas. Simultaneously, considering the morphological distortion characteristics of the spraying area (such as the coverage area changing from "circular" to "semi-circular" due to occlusion in complex geometric areas), a distortion coefficient k (ranging from 0.5 to 1, with k = 1 for no occlusion and k = 0.5 for full occlusion) is introduced to correct the risk range: when the second type of area is a deep groove (occlusion coefficient 0.6), the actual effective risk range = Δr × k = 167.2 × 0.6 ≈ 100.3mm; then, using the physical boundary line of the two types of areas (such as the connection line between the plane and the groove) as the reference axis... Define the "basic risk section" along the direction of the spray gun movement (from the first type of area to the second type of area): extend forward L1=r1×0.8 (covering 80% of the spraying range on the first type of area side to avoid missing edge risks), extend backward L2=r2×0.8 (covering 80% of the spraying range on the second type of area side). For example, when r1=250mm, L1=200mm, and when r2=82.8mm, L2=66.2mm. The total length of the basic risk section = 200+66.2=266.2mm. Next, perpendicular to the reference axis, expand the risk width to both sides (perpendicular to the spray gun's movement direction): For the first type of area, the expansion width W1 = r1 × 0.5 + Δr × 0.3 (0.5 is the base coverage coefficient, 0.3 is the abrupt change compensation coefficient), i.e., 250 × 0.5 + 167.2 × 0.3 ≈ 125 + 50.2 = 175.2 mm; for the second type of area, the expansion width W2 = r2 × 0.5 + Δr × 0.3 ≈ 82.8 × 0.5 + 50.2 ≈ 41.4 + 50.2 = 91.6 mm. Through the above calculations, the initial rectangular boundary of the sensitive zone is obtained: reference axis length 266.2 mm, first type of area width 175.2 mm, second type of area width 91.6 mm, forming an asymmetrical rectangular area; finally, the four right angles of the rectangular boundary are rounded to conform to the arc shape of the spray gun's spray range, etc., but not limited to this.

[0062] In one possible implementation, step S512, determining the initial sensitive zone region based on the abrupt change characteristics of the spraying range, includes:

[0063] S5121, Determine the regional boundary line based on the first type of region and the second type of region.

[0064] It can be understood that the region boundary line is the boundary line between the first type of region and the second type of region. This step is the "geometric reference anchoring" step for delineating the initial sensitive zone region. Its essence is to accurately identify the physical connection line between the first type of region (planar) and the second type of region (complex geometry), providing a "spatial reference axis" for subsequent determination of the region boundary based on the abrupt change characteristics of the spraying range. The output of the region boundary line can adopt a standardized coordinate format (such as the xyz coordinate sequence based on the aluminum workpiece coordinate system), with the interval between each coordinate point ≤0.1mm.

[0065] S5122, the region boundary is determined based on the abrupt change characteristics of the spraying range and the region boundary line.

[0066] For example, the first spraying range corresponding to the first type of region and the second spraying range corresponding to the second type of region can be extracted based on the abrupt change features of the spraying range. Then, an arbitrary boundary line tangent is generated based on the region boundary line. After aligning the intersection points of the edge lines of the first and second spraying ranges with the boundary line tangent and the region boundary line, the range of the first spraying range in the first type of region is extracted to obtain the first region boundary. The range of the second spraying range in the second type of region is extracted to obtain the second region boundary. The first and second region boundaries are then integrated to obtain the region boundary. Alternatively, the first spraying range and the second spraying range can be extracted in the same way. After the second spraying range, the first and second spraying ranges are tangent to each other. By increasing the radius, multiple intermediate spraying ranges from the first to the second spraying range are generated. These intermediate spraying ranges are inserted between the first and second spraying ranges at preset intervals. Finally, a line segment is generated that is tangent to the first, intermediate, and second spraying ranges. The area enclosed by the range on the side of the first spraying range away from the boundary line and the range on the side of the second spraying range away from the boundary line, and the tangent line segment, is used as the area boundary, and so on, but not limited to this.

[0067] In one possible implementation, step S5122, determining the region boundary based on the abrupt change characteristics of the spraying range and the region boundary line, includes:

[0068] S51221, based on the abrupt change features of the spraying range, extract the first spraying range corresponding to the first type of region and the second spraying range corresponding to the second type of region.

[0069] It can be understood that the first spraying range is the spraying range of the paint sprayed onto the aluminum surface when the spray gun sprays the first type of area, and the second spraying range is the spraying range of the paint sprayed onto the aluminum surface when the spray gun needs to spray the second type of area.

[0070] S51222, Generate a boundary line tangent based on the region boundary line.

[0071] It can be understood that the intersection of the boundary line tangent and the region boundary line passes through the line connecting the geometric center points of the first and second spraying areas. After confirming that the spray gun has completely moved from the position coordinates above the first type of region to the position coordinates above the second type of region, the first and second spraying areas are covered on the corresponding position coordinates. Then, the geometric center points of the first and second spraying areas are connected to obtain the intersection of the line connecting the geometric center points and the region boundary line. Finally, a tangent line tangent to the region boundary line is generated at this intersection, which is the boundary line tangent.

[0072] S51223, after aligning the intersection points of the edge lines of the first spraying range and the edge lines of the second spraying range with the tangent of the boundary line and the boundary line of the region, extract the range of the first spraying range in the first type of region to obtain the first region boundary, extract the range of the second spraying range in the second type of region to obtain the second region boundary, and integrate the first region boundary and the second region boundary to obtain the region boundary.

[0073] It can be understood that when the line connecting the geometric center points of the first and second spraying areas is perpendicular to the region boundary line, the size of the first region boundary is the first spraying area, and the size of the second region boundary is the second spraying area. When the line connecting the geometric center points of the first and second spraying areas is not perpendicular to the region boundary line, the size of the first region boundary is the area of ​​the first spraying area located within the first type of region, and the size of the second region boundary is the area of ​​the second spraying area located within the second type of region.

[0074] This setup aligns the first and second spraying areas with the area boundary lines and tangents, ensuring a seamless transition between the two types of areas and effectively eliminating coverage gaps and overlapping. Simultaneously, through the adaptive logic of "vertical rounding and non-vertical cutting," the boundary can both fully cover the risk area and conform to the area geometry. The resulting area boundary provides a high-precision benchmark for subsequent trajectory planning and smoothing parameter adjustments.

[0075] S5123, determine smoothing parameters based on abrupt changes in the spraying range.

[0076] For example, the difference between the radius of the first spraying range and the radius of the second spraying range can be obtained based on the abrupt change feature of the spraying range, and the smoothing parameter can be determined based on the difference; alternatively, the abrupt change feature of the spraying range can be input into the learning model, and the learning model can output the corresponding smoothing parameter.

[0077] In one possible implementation, in step S5123, determining smoothing parameters based on the abrupt changes in the spraying range includes:

[0078] S51231, Generate a mutation difference value based on the mutation characteristics of the spraying range; wherein, the mutation difference value is used to indicate the difference between the radius of the first spraying range and the radius of the second spraying range.

[0079] It can be understood that the mutation difference = |radius of the first spraying range - radius of the second spraying range|.

[0080] S51232, determine smoothing parameters based on mutation difference.

[0081] It is understandable that different mutation differences correspond to a smoothing parameter. The mutation differences can be matched with the corresponding smoothing parameter in an aluminum database; alternatively, the mutation differences can be input into a learning model, which outputs the corresponding smoothing parameter, and so on, but are not limited to these methods.

[0082] With this setup, by calculating the abrupt difference between the radii of the first and second spraying areas and determining the smoothing parameters based on this difference, a quantitative assessment and adaptive smoothing control of the severity of abrupt changes in the spraying area are achieved. Key parameters such as smoothing distance and rate can be dynamically adjusted according to the magnitude of the abrupt change, and the smoothing strategy is stronger when the abrupt change is larger.

[0083] S5124 adjusts the region boundary based on the smoothing parameter to obtain the initial sensitive zone region.

[0084] For example, the first maximum width of the region boundary in the first type of region and the second maximum width in the second type of region can be extracted respectively. Then, the two endpoints of the first maximum width are taken as the starting point and the two endpoints of the second maximum width are taken as the ending point. The starting point and the ending point on the same side are connected by a smoothing parameter to obtain two transition regions. Finally, the two transition regions are integrated with the region boundary to obtain the initial sensitive zone region. Alternatively, the region boundary can be symmetrically extended in the direction perpendicular to the boundary line according to the smoothing parameter to form a strip-shaped region containing the original region boundary as the initial sensitive zone region, and so on, but not limited to these.

[0085] This setup, by first determining the area boundary line, then combining the characteristics of abrupt changes in the spraying range to determine the area boundary, and then determining the smoothing parameters and adjusting the area boundary accordingly to obtain the initial sensitive zone area, forms a complete sensitive zone construction process of "geometric benchmark + parameter risk + smoothing adjustment". It can accurately locate and completely cover the coverage imbalance risk area caused by abrupt changes in the spraying range. At the same time, by adjusting the smoothing parameters, the boundary of the sensitive zone is adapted to the dynamic parameter changes of the transition area, effectively eliminating coverage discontinuities and overlapping accumulations at the boundary, and providing a high-precision and executable spatial framework for subsequent smoothing trajectory planning.

[0086] In one possible implementation, in step S5124, the region boundary is adjusted based on a smoothing parameter to obtain an initial sensitive zone region, including:

[0087] S51241, extract the first maximum width of the region boundary in the first type of region and the second maximum width in the second type of region respectively.

[0088] It can be understood that the maximum width refers to the lateral span of the area boundary perpendicular to the main movement direction of the spray gun (such as the X-axis along the length of the aluminum material). Its core is to quantify the actual lateral scale of the spray coverage area in the two types of areas, providing a dimensional benchmark for subsequent smooth transition. When the area boundary line is a straight line and the tangent of the boundary line coincides with the boundary line, the area boundary in the first type of area completely fits the outline of the first spray range. Therefore, the first maximum width is equal to the diameter of the first spray range (e.g., if the radius of the first spray range is 200mm and the diameter is 400mm, the first maximum width is 400mm). Similarly, the second maximum width is equal to the diameter of the second spray range (e.g., if the radius of the second spray range is 100mm and the diameter is 200mm, the second maximum width is 200mm). When the tangent of the boundary line does not coincide with the boundary line of the region (e.g., the boundary line of the region is curved, broken, or the tangent is offset due to geometric occlusion), the outline of the region boundary in the two types of regions will produce "asymmetric coverage" due to the change in the tangent direction. At this time, it is necessary to calculate the maximum width by traversing the coordinates: First, in the first type of region, along the direction perpendicular to the main movement of the spray gun (Y-axis), extract the Y values ​​of all coordinate points of the region boundary, and filter out the maximum Y value (Y1max) and the minimum Y value (Y1min). The difference between the two is the first maximum width (e.g., Y1max=250mm, Y1min=-150mm, first maximum width=250-(-150)=400mm); Similarly, in the second type of region, extract the maximum Y value (Y2max) and the minimum Y value (Y2min) of the boundary point. The difference is the second maximum width (e.g., Y2max=120mm, Y2min=-80mm, second maximum width=120-(-80)=200mm).

[0089] S51242, take the two endpoints of the first maximum width as the starting point and the two endpoints of the second maximum width as the ending point, and connect the starting point and the ending point on the same side with a smoothing parameter to obtain two transition regions.

[0090] This step is understandably crucial in transforming "quantified dimensional differences" into a "smooth geometric transition." At its core, while maintaining the principle of "top to top, bottom to bottom" pairing on the same side, a mathematical function (such as a linear, sigmoid, or Bézier curve) defined by smoothing parameters is used to generate two continuous, gradually changing transition curves between the corresponding endpoints of the first and second maximum widths. These two curves, together with the region boundary lines, form the upper and lower transition regions, respectively.

[0091] S51243 integrates the two transition regions with the region boundary to obtain the initial sensitive zone region.

[0092] This step can be understood as organically integrating the "original boundary" with the "smooth transition" to ultimately generate the initial sensitive zone region. Essentially, it involves a cropping-splitting-closing operation to seamlessly embed the upper and lower transition regions into the original region boundary, replacing the original "hard" boundary at the region boundary line. After integration, the boundary of the initial sensitive zone region retains its original shape in the portion far from the transition area, while within the transition area, it becomes a continuous curve controlled by smoothing parameters, forming a complete, closed region with smooth boundaries.

[0093] This setup, by first extracting the maximum width within the two regions, then connecting the endpoints on the same side with smooth parameters to generate a transition region, and finally integrating the transition region with the original region boundary, achieves precise geometric modeling from "step-like" width abrupt changes to "continuous and smooth" width variations, effectively eliminating coverage faults and paint accumulation at the boundary.

[0094] S513 determines the sensitive area based on the characteristics of sudden changes in spray flow rate and the initial sensitive zone region.

[0095] It is understandable that the magnitude and direction of the spray flow change can be determined based on the characteristics of the spray flow change mutation, and then the degree of impact caused by the flow change can be determined based on this. The adjustment range of the initial sensitive zone area can be determined according to the degree of impact, thereby determining the sensitive area. Alternatively, the rate of flow change can be determined based on the characteristics of the spray flow change mutation, and then a rate threshold can be set to determine whether the flow change is too drastic. If the threshold is exceeded, the length of the initial sensitive zone area can be dynamically expanded according to the excess ratio to reduce the actual rate of change.

[0096] With such settings, by first splitting the spraying range and flow rate, two core mutation features, from the parameter mutation features, then constructing an initial sensitive zone to lock the geometric coverage risk based on the range mutation feature, and finally dynamically adjusting the initial zone in combination with the flow rate mutation feature, a hierarchical control of "geometric risk positioning + precise adjustment of physical deposition risk" is achieved. This not only enables the sensitive area to completely wrap the coverage imbalance area caused by range mutation, but also accurately captures the thickness fluctuation risk through the correction of the flow rate factor, making the final sensitive area have both geometric accuracy and physical relevance, providing a comprehensive and accurate risk guidance for subsequent trajectory planning, effectively eliminating the yin-yang surface caused by the double mutation of range and flow rate in the transition area, and significantly improving the stability of the appearance and coating quality of aluminum spraying.

[0097] In a possible implementation manner, in step S513, determining the sensitive area based on the spraying flow rate mutation feature and the initial sensitive zone includes:

[0098] S5131, generating a mutation vector based on the spraying flow rate mutation feature; wherein, the mutation vector is used to indicate the amplitude and direction of the change in the spraying flow rate.

[0099] It can be understood that this step is the core link to transform the spraying flow rate mutation feature from "qualitative description" to "quantitative vector". Its essence is to provide a standardized quantitative basis for accurately evaluating the impact of the flow rate on the coating in the form of a mathematical vector, which includes both the "amplitude" (size) and "direction" (increase or decrease trend) of the flow rate change. For the amplitude, first extract the reference spraying flow rate Q1 (such as 12 ml / s) of the first type of area and the target spraying flow rate Q2 (such as 7 ml / s) of the second type of area, and calculate the flow rate mutation amplitude ΔQ = |Q1 - Q2| (in the above example, ΔQ = 5 ml / s) through the absolute difference. This value directly reflects the severity of the flow rate change, and the larger the value, the more significant the potential impact on the coating thickness uniformity. For the direction, distinguish the flow rate change trend through the sign: when Q1 > Q2 (the flow rate decreases from the first type of area to the second type of area), the direction is defined as "negative" (can be marked as -1); when Q1 < Q2 (the flow rate increases from the first type of area to the second type of area), the direction is defined as "positive" (can be marked as +1); finally, integrate the amplitude and direction into the mutation vector V_Q = (ΔQ, dir) (in the above example, V_Q = (5, -1)).

[0100] S5132, determining the flow rate influence coefficient based on the amplitude of the mutation vector.

[0101] It is understandable that different magnitudes correspond to a flow impact coefficient. By establishing the key link between the "flow mutation magnitude" and the "coating impact degree," a "flow impact coefficient" can be directly used for sensitive area adjustments. This coefficient quantifies the intensity of the need for adjusting the initial sensitive zone boundary due to the flow mutation. A positive correlation logic of "the larger the magnitude, the larger the impact coefficient" is adopted: for piecewise linear mapping, when ΔQ≤2ml / s (slight mutation), the flow impact coefficient K can be set to 0.2; when 2ml / s<ΔQ≤5ml / s (moderate mutation), K=0.5; when ΔQ>5ml / s (severe mutation), K=0.8. This piecewise division enables differentiated assessment of different mutation degrees.

[0102] S5133, the offset is determined based on the flow influence coefficient; wherein, the flow influence coefficient is inversely proportional to the offset.

[0103] This step can be understood as a bridge between the "flow impact coefficient" and the "spatial adjustment amount of the sensitive area." Essentially, it calculates the specific distance (offset) that the initial sensitive zone boundary needs to be offset based on the core rule that "the flow impact coefficient is inversely proportional to the offset." This distance directly determines the spatial scale of the sensitive area adjustment. For example, the flow impact coefficient can be output as the corresponding offset through a database or learning model.

[0104] S5134, based on the offset and the direction of the mutation vector, the boundary coordinates of the initial sensitive zone are offset and adjusted to obtain the sensitive zone; wherein, the boundary of the initial sensitive zone on the side closer to the area with a larger flow value remains unchanged.

[0105] It can be understood that keeping the coordinates of the boundary of the initial sensitive zone region closer to the area with a larger flow rate unchanged means that: if the flow rate decreases from the first type of region (Q1=12ml / s) to the second type of region (Q2=7ml / s) (the direction of the mutation vector is negative), then the "area with a larger flow rate" is the first type of region, and the boundary of the initial sensitive zone region closer to the first type of region needs to be fixed (e.g., the X coordinate X1=130mm remains unchanged); if the flow rate increases from the first type of region (Q1=7ml / s) to the second type of region (Q2=12ml / s) (the direction of the mutation vector is positive), then the "area with a larger flow rate" is the second type of region, and the boundary of the initial sensitive zone region closer to the second type of region needs to be fixed (e.g., the X coordinate X2=230mm remains unchanged). Fixing the boundary on the high flow rate side can avoid insufficient coverage of the high flow rate area due to adjustments, while ensuring that adjustments focus on the low flow rate or the transition zone of flow rate changes, accurately responding to the risk of thickness fluctuations. From the perspective of directional matching adjustment, the spatial direction of the boundary offset needs to be determined according to the direction of the mutation vector: when the direction is negative (flow rate decreases), the side of the initial sensitive zone that is far from the fixed boundary (closer to the boundary of the second type of region, such as the original X coordinate X2=230mm) needs to be offset towards the direction of the second type of region (positive X-axis direction), and the offset distance is D calculated by S5133 (such as D≈11.1mm in the example above). After adjustment, the new boundary coordinates are X2'=230+11.1=241.1mm; when the direction is positive (flow rate increases), the side that is far from the fixed boundary (closer to the boundary of the first type of region, such as the original X coordinate X1=130mm) needs to be offset towards the direction of the first type of region (negative X-axis direction), and the new boundary coordinates are X1'=130-D; the offset direction is consistent with the direction of flow rate change, so that the sensitive area can cover the thickness anomaly area caused by the flow rate change.

[0106] This setup, by transforming the characteristics of sudden changes in spray flow rate into a change vector containing amplitude and direction, determines the flow rate influence coefficient based on the amplitude and generates an offset according to an inverse relationship, and then directionally offsets the initial sensitive zone boundary along the change direction (fixing the high flow rate side boundary), achieves a precise match between the risk of sudden flow rate changes and the spatial adjustment of the sensitive area. The more severe the flow rate change, the smaller the offset to focus on the high-risk area. At the same time, directional matching and boundary fixing ensure that the adjustment does not overlook risks and does not affect the coverage of the high flow rate area. This ensures that the final sensitive area can completely cover the coating thickness fluctuation area caused by the flow rate change and also has a geometric shape that adapts to the flow rate change pattern.

[0107] S520 generates spray gun motion compensation trajectory based on sensitive area and parameter mutation characteristics.

[0108] For example, a curve showing the change in distance between the spray gun and the aluminum surface within the sensitive area can be generated based on the sensitive area and parameter abrupt change characteristics. Then, a curve showing the change in speed of the spray gun within the sensitive area can be generated based on the parameter abrupt change characteristics and the basic spray gun motion trajectory. The kernel then obtains the spray gun motion compensation trajectory. Alternatively, the boundary of the sensitive area (the leading and trailing edges along the direction of motion) can be defined as a virtual wall. When the spray gun approaches the virtual wall (i.e., enters the first half of the sensitive area), the system gradually reduces the motion speed v_gun according to the distance from the virtual wall and simultaneously adjusts the spraying range α. The closer to the virtual wall, the greater the speed reduction and the smoother the parameter adjustment. When the spray gun moves away from the virtual wall (i.e., leaves the second half of the sensitive area), it gradually returns to normal speed and parameters; and so on, but not limited to these.

[0109] This setup, by first accurately locating sensitive areas prone to uneven coating based on parameter mutation characteristics, and then generating a spray gun motion compensation trajectory by combining the spatial constraints of the sensitive areas with parameter mutation characteristics (spraying range, flow rate changes, etc.), achieves closed-loop control of "risk area locking - targeted trajectory generation". This not only allows the trajectory to focus on the core area of ​​transition risk, but also actively compensates for coating unevenness caused by parameter mutation by dynamically adjusting the spray gun motion parameters (speed, distance, etc.). This enables the spray gun to smoothly transition between motion and parameters when crossing two types of areas, effectively eliminating uneven coating defects and significantly improving the uniformity of aluminum coating thickness and the stability of appearance quality.

[0110] In one possible implementation, step S520 generates a spray gun motion compensation trajectory based on the sensitive area and parameter abrupt change characteristics, including:

[0111] S521, a basic spray gun motion trajectory is generated based on the sensitive area and parameter abrupt change characteristics; wherein, the basic spray gun motion trajectory is used to reflect the change curve of the distance between the spray gun and the aluminum surface in the sensitive area.

[0112] This step, as understood, is the "spatial baseline construction" stage for generating the spray gun's motion compensation trajectory. Essentially, it involves planning a dynamic curve of the distance (spraying distance) between the spray gun and the aluminum surface based on the geometric contour and parameter abrupt change characteristics of the sensitive area. Distance adjustment helps balance the differences in paint deposition caused by abrupt changes in spray range and flow rate. This step revolves around "distance baseline setting - abrupt change characteristic matching - curve smoothing generation," ensuring that distance changes both adapt to the spatial morphology of the sensitive area and coordinate with parameter abrupt changes to achieve coating uniformity control. From the perspective of distance baseline setting, standard spraying distances for two types of areas are first determined (e.g., baseline distance d1 = 250mm for the first type of area, and baseline distance d2 = 200mm for the second type of area). This baseline is calibrated based on the paint atomization effect and electrostatic adsorption efficiency. Distance changes within the sensitive area must use these two baselines as the starting and ending points to avoid deviating from the reasonable range of the process. From the perspective of abrupt change feature matching, if the spraying range suddenly shrinks in the parameter abrupt change feature (e.g., from 90° to 45°), to compensate for the potential localized paint buildup caused by the reduced coverage area, the spraying distance needs to gradually increase from d1 to d2 in the sensitive area (increasing the distance reduces the amount of paint deposited per unit area). If the flow rate suddenly increases, the effect of the increased flow rate needs to be offset by increasing the distance; conversely, if the flow rate suddenly decreases, the rate of increase in distance can be appropriately slowed down. An S-curve or Bézier curve can be used as the distance change curve to ensure a smooth transition from d1 to d2. For example, the distance adjustment can be started slowly at the entrance of the sensitive area, changed at a rate matching the magnitude of the parameter abrupt change in the middle section, and smoothly terminated at the exit, reducing new coating fluctuations caused by sudden distance changes. The final generated basic spray gun trajectory (distance change curve) is then determined.

[0113] S522 generates a speed control curve based on parameter mutation characteristics and the basic spray gun motion trajectory; the speed control curve is used to reflect the speed change of the spray gun moving in the sensitive area.

[0114] It can be understood that this step, based on the "spatial reference" determined in S521, superimposes the key element of "time dimension" control. Essentially, it dynamically plans the spray gun's movement speed based on parameter mutation characteristics and the baseline distance trajectory, achieving precise control of coating thickness through deep coupling of "speed-flow-distance". For example, the baseline spray gun movement trajectory can be divided into multiple continuous control segments, then a reference speed corresponding to each control segment can be generated based on parameter mutation characteristics, and finally, multiple reference speeds can be combined to form a speed control curve. Alternatively, a real-time mapping model between speed and parameter mutation characteristics can be established, calculating the required instantaneous speed in real time based on the instantaneous position of the spray gun within the sensitive area, and fitting it into a smooth speed control curve.

[0115] In one possible implementation, step S522 involves generating a speed control curve based on parameter mutation characteristics and the basic spray gun motion trajectory, including:

[0116] S5221 divides the basic spray gun movement trajectory into multiple continuous control segments.

[0117] This step can be understood as a preprocessing stage that "discretizes" the complex continuous trajectory into easily computed and controllable units. Essentially, it creates independent "control windows" for subsequent segmented velocity planning. By analyzing the characteristics of parameter abrupt changes (such as flow rate curves), control segments are divided more densely in areas of drastic parameter changes (such as near the boundary line), and more sparsely in areas of gradual parameter changes. For example, if the flow rate changes by 80% within 20 mm before and after the boundary line, then a segment is drawn every 5 mm within this range; while in areas far from the boundary, a segment is drawn every 20 mm.

[0118] S5222 generates a reference speed corresponding to the control segment based on parameter mutation characteristics.

[0119] This step is the core calculation process for assigning specific "control targets" to each "control window." Essentially, it calculates an optimal, constant baseline speed for each control segment based on parameter mutation characteristics. The baseline speed for each control segment can be obtained through a speed calculation model: the ideal coating thickness T is directly proportional to the spray flow rate Q and inversely proportional to the spray gun speed v and spray width W, i.e., T∝Q / (v×W). To maintain the target thickness Ttarget when parameters change, the speed needs to be adjusted accordingly. Therefore, the formula for calculating the baseline speed vi for each control segment i can be expressed as: vi=K×Qi÷(Wi×Ttarget). Here, K is a comprehensive constant related to factors such as coating density and atomization efficiency, which can be obtained through process calibration; Qi is the target flow rate in the i-th control segment, obtained from the value of the spray flow mutation characteristic (such as the Sigmoid transition curve) at the center point of that segment; and Wi is the target spray width in the i-th control segment, obtained from the spray range mutation characteristic and the basic distance trajectory di in S5221.

[0120] S5223 generates speed control curves from multiple reference speeds.

[0121] This step can be understood as a smoothing process that transforms a series of discrete control objectives into a single continuous control command. Essentially, it involves interpolating (e.g., linear difference, spline curve difference) and filtering multiple reference velocities to generate a continuous, smooth speed control curve that can be directly used by the actuator. For example, if 14 control segments calculate 14 reference velocities, these 14 (position, velocity) data points, along with the entry point (x_start, v1) and exit point (x_end, v2), are first used as control points for a B-spline curve. Then, a speed control curve that smoothly transitions across all points is fitted using the B-spline algorithm.

[0122] This setup, by dividing the basic spray gun trajectory into multiple continuous control segments, generates a corresponding reference speed for each control segment based on parameter mutation characteristics, and then smoothly fits multiple reference speeds into a speed control curve, achieves segmented fine planning and global smooth transition of speed in sensitive areas. It can both perform differentiated speed compensation according to the intensity of parameter mutation in each segment and ensure the smoothness of the entire trajectory.

[0123] S523 generates a spray gun motion compensation trajectory by integrating the basic spray gun motion trajectory and speed control curve in a time sequence.

[0124] It is understandable that, through precise time-series calculations, a unique timestamp is assigned to each spatial position of the spray gun within the sensitive area. This timestamp includes the distance between the spray gun and the aluminum surface, as well as the instantaneous velocity of the spray gun at that position, thereby generating a spatiotemporally coupled and continuous motion compensation trajectory. First, synchronous spatial sampling is performed on two curves along the main motion direction of the sensitive area to obtain the position, distance, and velocity of each sampling point. Next, the local motion time between adjacent sampling points is calculated and accumulated to generate a unique arrival timestamp for each spatial point, establishing a precise spatiotemporal mapping. Then, the generated trajectory is checked against kinematic constraints such as acceleration and jerk. If these constraints are not met, the process returns to optimizing the velocity curve and reintegrating it. Finally, the validated spatiotemporal trajectory data is converted into a recognizable list of points or high-order spline curve parameters, thereby generating a spatiotemporally coupled, smooth, continuous final spray gun motion compensation trajectory that meets the physical limitations of the equipment.

[0125] This setup, through a layered trajectory generation logic of "spatial benchmark construction - temporal dimension superposition - spatiotemporal coupling integration," first plans the dynamic change curve (basic trajectory) of the spray gun distance to the aluminum surface based on the sensitive area and parameter mutation characteristics. Then, it matches the differentiated speed control curve with the basic trajectory based on the parameter mutation characteristics. Finally, it establishes a precise mapping between spatial position and time through temporal integration and verifies kinematic constraints. This achieves three-dimensional collaborative compensation of the spray gun movement in terms of "distance-speed-time," which not only accurately offsets the fluctuation of coating thickness in the sensitive area due to parameter mutation, but also makes the spray gun movement smooth and impact-free, effectively eliminating defects on uneven surfaces and significantly improving the appearance quality and process execution stability of aluminum coating.

[0126] It should be understood that the sequence number of each step in the above embodiments does not imply the order of execution. The execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of this application.

[0127] Corresponding to the electrostatic spray gun motion compensation method for eliminating uneven surfaces in aluminum spraying described in the above embodiments, this application also provides an electrostatic spray gun motion compensation system for eliminating uneven surfaces in aluminum spraying. Each module of this system can realize each step of the electrostatic spray gun motion compensation method for eliminating uneven surfaces in aluminum spraying. Figure 3 The diagram shows a structural block diagram of an electrostatic spray gun motion compensation system for eliminating uneven surfaces in aluminum spraying, as provided in an embodiment of this application. For ease of explanation, only the parts relevant to the embodiments of this application are shown.

[0128] Reference Figure 3 The electrostatic spray gun motion compensation system for eliminating uneven coating on aluminum materials includes:

[0129] The acquisition module is used to acquire surface structure information of aluminum materials.

[0130] The determination module is used to determine a first type of region and a second type of region based on the surface structure information of the aluminum material; wherein, the first type of region is used to indicate the region where the aluminum material structure is planar, and the second type of region is used to indicate the region where the aluminum material structure is complex geometry, and the first type of region and the second type of region are adjacent.

[0131] The first generation module is used to generate first spraying parameters based on a first type of region and second spraying parameters based on a second type of region.

[0132] The second generation module is used to generate parameter mutation features based on the first and second spraying parameters; wherein, the parameter mutation features are used to reflect the changes in the spraying parameters of the spray gun.

[0133] The third generation module is used to generate a spray gun motion compensation trajectory based on parameter change characteristics when the spray gun is detected moving from the first type of area to the second type of area, and to control the spray gun to adjust the first spraying parameters to the second spraying parameters, while moving from the first type of area to the second type of area using the spray gun motion compensation trajectory.

[0134] It should be noted that the information interaction and execution process between the above modules are based on the same concept as the method embodiments of this application. For details on their specific functions and technical effects, please refer to the method embodiments section, which will not be repeated here.

[0135] Those skilled in the art will understand that, for the sake of convenience and brevity, the above-described module division is merely an example. In practical applications, the above functions can be assigned to different modules as needed, that is, the internal structure of the system can be divided into different modules to complete all or part of the functions described above. The modules in the embodiments can be integrated into one processing unit, or each module can exist physically separately, or two or more modules can be integrated into one unit. The integrated unit can be implemented in hardware or as a software functional unit. Furthermore, the specific names of the modules are only for easy differentiation and are not intended to limit the scope of protection of this application. The specific working process of the modules in the above system can be referred to the corresponding process in the foregoing method embodiments, and will not be repeated here.

[0136] This application embodiment also provides an electrostatic spray gun motion compensation device for eliminating uneven surfaces in aluminum spraying, including a spraying device and a control device, wherein the control device is electrically connected to the spraying device. Figure 4 This is a schematic diagram of the structure of a control device 6 provided in an embodiment of this application. Figure 4 As shown, the control device 6 in this embodiment includes: at least one processor 60 ( Figure 4 Only one is shown in the image), at least one memory 61 ( Figure 4 (Only one is shown in the image) and a computer program 62 stored in the at least one memory 61 and executable on the at least one processor 60. When the processor 60 executes the computer program 62, it causes the control device 6 to perform the steps in any of the above embodiments of the electrostatic spray gun motion compensation method for eliminating the uneven surfaces of aluminum spraying, or causes the control device 6 to perform the functions of each module in the above system embodiments.

[0137] For example, the computer program 62 may be divided into one or more modules / units, which are stored in the memory 61 and executed by the processor 60 to complete this application. The one or more modules / units may be a series of computer program instruction segments capable of performing a specific function, which describe the execution process of the computer program 62 in the control device 6.

[0138] The control device 6 can be a desktop computer, laptop, handheld computer, or cloud server, etc. The electrostatic spray gun motion compensation device for eliminating uneven coating on aluminum materials may include, but is not limited to, a processor 60 and a memory 61. Those skilled in the art will understand that... Figure 4 This is merely an example of control device 6 and does not constitute a limitation on control device 6. It may include more or fewer components than shown, or combine certain components, or different components, such as input / output devices, network access devices, buses, etc.

[0139] The processor 60 can be a Central Processing Unit (CPU), or it can be other general-purpose processors, digital signal processors (DSPs), application-specific integrated circuits (ASICs), field-programmable gate arrays (FPGAs), or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. The general-purpose processor can be a microprocessor or any conventional processor.

[0140] In some embodiments, the memory 61 may be an internal storage unit of the control device 6, such as a hard disk or memory of the control device 6. In other embodiments, the memory 61 may be an external storage device of the control device 6, such as a plug-in hard disk, smart media card (SMC), secure digital (SD) card, flash card, etc., equipped on the control device 6. Furthermore, the memory 61 may include both internal storage units and external storage devices of the control device 6. The memory 61 is used to store operating systems, applications, bootloaders, data, and other programs, such as the program code of computer programs. The memory 61 can also be used to temporarily store data that has been output or will be output.

[0141] This application also provides a computer-readable storage medium storing a computer program that, when executed by a processor, implements the steps in any of the above method embodiments.

[0142] This application provides a computer program product that, when running on an electrostatic spray gun motion compensation device for eliminating uneven surfaces in aluminum spraying, enables the electrostatic spray gun motion compensation device for eliminating uneven surfaces in aluminum spraying to perform the steps in any of the above-described method embodiments.

[0143] If the integrated unit is implemented as a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, all or part of the processes in the methods of the above embodiments can be implemented by a computer program instructing related hardware. The computer program can be stored in a computer-readable storage medium, and when executed by a processor, it can implement the steps of the various method embodiments described above. The computer program includes computer program code, which can be in the form of source code, object code, executable files, or certain intermediate forms. The computer-readable medium can include at least: any entity or device capable of carrying the computer program code to the electrostatic spray gun motion compensation device for eliminating uneven surfaces in aluminum spraying, a recording medium, a computer memory, a read-only memory (ROM), a random access memory (RAM), an electrical carrier signal, a telecommunication signal, and a software distribution medium. Examples include USB flash drives, portable hard drives, magnetic disks, or optical disks.

[0144] In the above embodiments, the descriptions of each embodiment have different focuses. For parts that are not described in detail or recorded in a certain embodiment, please refer to the relevant descriptions of other embodiments.

[0145] Those skilled in the art will recognize that the units and algorithm steps of the various examples described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are implemented in hardware or software depends on the specific application and design constraints of the technical solution. Those skilled in the art can use different methods to implement the described functions for each specific application, but such implementation should not be considered beyond the scope of this application.

[0146] In the embodiments provided in this application, it should be understood that the disclosed electrostatic spray gun motion compensation device and system for eliminating uneven surfaces in aluminum spraying can be implemented in other ways. For example, the embodiments of the electrostatic spray gun motion compensation system for eliminating uneven surfaces in aluminum spraying described above are merely illustrative. For instance, the division of modules is only a logical functional division, and in actual implementation, there may be other division methods. For example, multiple modules may be combined or integrated into another system, or some features may be ignored or not executed. Furthermore, the coupling or direct coupling or communication connection shown or discussed may be indirect coupling or communication connection through some interfaces, devices, or modules, and may be electrical, mechanical, or other forms.

[0147] The modules described as separate components may or may not be physically separate. The components shown as modules may or may not be physical modules; that is, they may be located in one place or distributed across multiple network units. Some or all of the modules can be selected to achieve the purpose of this embodiment according to actual needs.

[0148] The above-described embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this application, and should all be included within the protection scope of this application.

Claims

1. A method for compensating the motion of an electrostatic spray gun to eliminate uneven coating on aluminum materials, characterized in that, include: Obtain information on the surface structure of aluminum materials; Based on the surface structure information of the aluminum material, a first type of region and a second type of region are determined; wherein, the first type of region is used to indicate a region where the aluminum material structure is planar, and the second type of region is used to indicate a region where the aluminum material structure is complex geometry, and the first type of region and the second type of region are adjacent to each other; First spraying parameters are generated based on the first type of region, and second spraying parameters are generated based on the second type of region; wherein, the first spraying parameters are different from the second spraying parameters; A parameter mutation feature is generated based on the first spraying parameter and the second spraying parameter; wherein, the parameter mutation feature is used to reflect the changes in the spraying parameters of the spray gun; When the spray gun is detected moving from the first type of area to the second type of area, a spray gun motion compensation trajectory is generated based on the parameter change feature, and the spray gun is controlled to adjust the first spraying parameter to the second spraying parameter, while moving from the first type of area to the second type of area according to the spray gun motion compensation trajectory. The generation of the spray gun motion compensation trajectory based on the parameter mutation characteristics includes: Sensitive regions are determined based on the parameter mutation characteristics; wherein, the sensitive regions are used to reflect the areas where the spray gun is prone to forming yin-yang surfaces after moving from the first type of region to the second type of region; The spray gun motion compensation trajectory is generated based on the sensitive area and the parameter mutation characteristics.

2. The electrostatic spray gun motion compensation method for eliminating uneven coating on aluminum materials as described in claim 1, characterized in that, The determination of sensitive regions based on the parameter mutation features includes: Based on the parameter mutation features, spraying range mutation features and spraying flow rate mutation features are extracted; wherein, the spraying range mutation features are used to reflect the changes in the coating particles sprayed from the spray gun covering the aluminum surface, and the spraying flow rate mutation features are used to reflect the density changes of the coating particles sprayed from the spray gun. The initial sensitive zone region is determined based on the abrupt change characteristics of the spraying range; The sensitive area is determined based on the characteristics of the sudden change in spray flow rate and the initial sensitive zone region.

3. The electrostatic spray gun motion compensation method for eliminating uneven coating on aluminum materials as described in claim 2, characterized in that, The determination of the initial sensitive zone region based on the abrupt change characteristics of the spraying range includes: Determine the regional boundary line based on the first type of region and the second type of region; The region boundary is determined based on the abrupt change characteristics of the spraying range and the region boundary line; Smoothing parameters are determined based on the abrupt changes in the spraying range; The region boundary is adjusted based on the smoothing parameters to obtain the initial sensitive zone region.

4. The electrostatic spray gun motion compensation method for eliminating uneven coating on aluminum materials as described in claim 3, characterized in that, The determination of the region boundary based on the abrupt change characteristics of the spraying range and the region boundary line includes: Based on the abrupt change features of the spraying range, the first spraying range corresponding to the first type of region and the second spraying range corresponding to the second type of region are extracted; Generate a boundary line tangent based on the region boundary line; After aligning the intersections of the edge of the first spraying range and the edge of the second spraying range with the tangent of the boundary line and the boundary line of the region, the range of the first spraying range in the first type of region is extracted to obtain the first region boundary. The range of the second spraying range in the second type of region is extracted to obtain the second region boundary. The first region boundary and the second region boundary are then integrated to obtain the region boundary.

5. The electrostatic spray gun motion compensation method for eliminating uneven coating on aluminum materials as described in claim 4, characterized in that, The determination of smoothing parameters based on the abrupt change characteristics of the spraying range includes: A mutation difference is generated based on the abrupt change characteristics of the spraying range; wherein, the mutation difference is used to indicate the difference between the radius of the first spraying range and the radius of the second spraying range; The smoothing parameters are determined based on the mutation difference.

6. The electrostatic spray gun motion compensation method for eliminating uneven coating on aluminum materials as described in claim 3, characterized in that, The step of adjusting the region boundary based on the smoothing parameter to obtain the initial sensitive zone region includes: Extract the first maximum width of the region boundary in the first type of region and the second maximum width in the second type of region, respectively; Using the two endpoints of the first maximum width as the starting point and the two endpoints of the second maximum width as the ending point, the starting point and the ending point on the same side are connected by the smoothing parameter to obtain two transition regions. The two transition regions are integrated with the region boundary to obtain the initial sensitive zone region.

7. The electrostatic spray gun motion compensation method for eliminating uneven coating on aluminum materials as described in claim 2, characterized in that, The determination of the sensitive region based on the spray flow rate mutation characteristics and the initial sensitive zone region includes: A mutation vector is generated based on the mutation characteristics of the spraying flow rate; wherein, the mutation vector is used to indicate the magnitude and direction of the change in the spraying flow rate; The flow impact coefficient is determined based on the magnitude of the mutation vector; The offset is determined based on the flow rate influence coefficient; wherein the flow rate influence coefficient is inversely proportional to the offset. Based on the offset and the direction of the mutation vector, the boundary coordinates of the initial sensitive zone are offset and adjusted to obtain the sensitive zone; wherein, the boundary of the initial sensitive zone on the side closer to the area with a larger flow value remains unchanged in coordinates.

8. The electrostatic spray gun motion compensation method for eliminating uneven coating on aluminum materials as described in claim 1, characterized in that, The generation of the spray gun motion compensation trajectory based on the sensitive region and the parameter abrupt change characteristics includes: A basic spray gun motion trajectory is generated based on the sensitive area and the parameter abrupt change characteristics; wherein, the basic spray gun motion trajectory is used to reflect the change curve of the distance between the spray gun and the aluminum surface in the sensitive area; A speed control curve is generated based on the parameter mutation characteristics and the basic spray gun trajectory; wherein, the speed control curve is used to reflect the speed change of the spray gun moving in the sensitive area; Based on the basic spray gun motion trajectory and the speed control curve, a time-series integration is performed to generate a spray gun motion compensation trajectory.

9. The electrostatic spray gun motion compensation method for eliminating uneven coating on aluminum materials as described in claim 8, characterized in that, The generation of the speed control curve based on the parameter mutation characteristics and the basic spray gun motion trajectory includes: The basic spray gun trajectory is divided into multiple continuous control segments; A reference speed corresponding to the control segment is generated based on the parameter mutation characteristics. Generate speed control curves from the multiple reference speeds.

Images