Nickel-zinc ion content automatic monitoring device for electroplating and identification method

Abstract

The application discloses a kind of electroplating nickel zinc ion content automatic monitoring device and identification method, belong to electroplating online monitoring and optical detection field.For the problem that colorless zinc ions in nickel-zinc alloy electroplating solution are difficult to be directly visually perceived and production line bubbles, turbidity fluctuation interference is serious, the application includes flow detection unit, composite light source module, high robust imaging module and control and calculation unit.During detection, characteristic transmission image and background grating distortion image are collected according to time sequence trigger;flat field correction is used to restore transmission information, by extracting turbidity-free relative absorbance and visual sub-pixel offset, and constructing lower triangular decoupling matrix equation, the concentration of chromogenic nickel ions and colorless zinc ions is simultaneously and stably solved.The application breaks through the bottleneck of perceiving colorless ions in mixed solution, improves the detection robustness under complex working conditions, and has strong industrial practical value.

Description

Technical Field

[0001] This invention relates to the fields of online monitoring in electroplating manufacturing and optical precision testing technology, and particularly to an automatic monitoring device and identification method for nickel-zinc ion content in electroplating. Background Technology

[0002] Nickel-zinc alloy electroplating is widely used in the electroplating manufacturing of precision hardware, automotive parts, and electronic connectors. During nickel-zinc alloy electroplating, the ratio of nickel to zinc in the plating layer directly determines the corrosion resistance and ductility of the final product. Therefore, accurately monitoring and controlling the concentration and ratio of nickel and zinc ions in the electroplating solution is crucial. An imbalance in ion concentration can easily lead to a decrease in the corrosion resistance of the entire batch of electroplated products or cause the plating layer to crack and peel off. Existing electroplating solution ion content detection technologies have the following significant technical shortcomings:

[0003] Firstly, chemical titration suffers from significant time lag and is prone to secondary pollution: Currently, most production lines rely on manual sampling or automated titrators (such as EDTA complexometric titration) for chemical analysis. This traditional method takes 15 to 30 minutes per test, resulting in severe detection lag, which cannot meet the dynamic requirements of high-speed continuous electroplating production lines for real-time online replenishment of chemicals. In addition, the titration process continuously consumes a large amount of chemical reagents, inevitably generating difficult-to-treat secondary waste liquid, resulting in high environmental protection and compliance costs.

[0004] Secondly, contact electrochemical sensors are highly susceptible to contamination, leading to signal drift or even failure. Some production lines have attempted to use ion-selective electrodes (ISEs) directly immersed in electroplating tanks or pipelines for online detection. However, electroplating solutions contain high concentrations of organic additives (such as brighteners and carriers) and active metal ions. These substances readily undergo physical adsorption, chemical passivation, or reduction reactions on the sensor probe surface, causing rapid probe contamination and severe thermal drift and baseline shift in the detection signal. This necessitates frequent shutdowns for manual cleaning and recalibration, resulting in extremely high maintenance costs and difficulty in guaranteeing long-term robustness.

[0005] Third, traditional optical and visual technologies are ill-suited to complex working conditions and suffer from a blind spot in colorless ion perception: conventional UV-Vis spectrophotometers are only suitable for ideal, static, and clear laboratory measurement conditions. However, in the circulating pipelines of electroplating production lines, microbubbles, variations in the turbidity of the substrate, and drastic temperature fluctuations are unavoidable. These fluid interference factors cause drastic and random attenuation of transmitted light intensity, completely masking the true absorbance differences caused by changes in ion concentration. Even more critically, while nickel ions have significant absorption peaks in specific wavelength ranges, zinc ions are colorless and transparent in the visible to near-infrared range. This renders traditional machine vision or single-dimensional spectroscopy techniques completely incapable of directly capturing and quantitatively identifying the visual characteristics of zinc ions in mixed solutions. Summary of the Invention

[0006] The purpose of this invention is to overcome the shortcomings of the prior art. The first aspect of this invention provides an automatic monitoring and identification method for the content of nickel and zinc ions in electroplating, in order to solve the technical problems of chemical titration lag, easy contamination and failure of electrode sensors, and the inability of traditional optical technology to identify colorless and transparent zinc ions in the mixed solution in the prior art.

[0007] To address the aforementioned technical problems, the first aspect of this invention provides an automatic monitoring and identification method for the content of nickel-zinc ions in electroplated metals, comprising the following steps:

[0008] Step S1, Multimodal Image Synchronous Acquisition: Under the trigger of the control and computing unit, The feature measurement light source in the composite light source module is constantly illuminated, and the highly robust imaging module exposes and acquires feature transmission images; The reference baseline light source in the composite light source module is constantly illuminated, and the high-robust imaging module exposes and acquires a background raster distortion image.

[0009] Step S2, Anti-interference image preprocessing: The pixel grayscale value correction is calculated for the feature transmission image and the background grating distortion image respectively using the flat field correction algorithm to obtain the corrected feature transmission image and the corrected background grating distortion image;

[0010] Step S3, Physical Feature Extraction and Mapping: Extract the average gray values ​​of the corrected feature transmission image and the corrected background grating distortion image in the region of interest, and extract the turbidity relative absorbance by calculating the logarithmic ratio of the corresponding wavelength; use a sub-pixel edge detection operator to locate the current stripe spacing of the background calibration target in the corrected background grating distortion image, and perform a differential comparison with the pure water reference spacing to extract the visual sub-pixel offset;

[0011] Step S4: Multi-parameter simultaneous decoupling calculation: Based on the principle of single-variable correlation of absorbance and linear superposition of multiple variables of refractive index, construct a lower triangular decoupling matrix equation. Independently solve the nickel ion concentration by combining the first row of the lower triangular decoupling matrix equation with the relative absorbance of turbidity. Substitute the nickel ion concentration into the second row of the lower triangular decoupling matrix equation and solve the zinc ion concentration by combining the visual sub-pixel offset, and output the comprehensive judgment result.

[0012] Further, in step S2, the specific formula for calculating pixel grayscale value correction using the flat-field correction algorithm is as follows:

[0013] ;

[0014] in, The pixel grayscale values ​​are those of the original acquired feature transmission image or the background raster distortion image. The pixel grayscale value of the dark field image of the high-robust imaging module. To calibrate the pixel grayscale values ​​of a brightfield image for pure water, This refers to the grayscale values ​​of the pixels in the corrected output image.

[0015] Further, in step S3, the turbidity-reduced relative absorbance is extracted. The specific formula is:

[0016] ;

[0017] in, The average gray value of the corrected feature transmission image in the region of interest. The average grayscale value of the corrected background raster distortion image in the region of interest; extract the visual subpixel offset. The specific formula is:

[0018] ;

[0019] in, For the current stripe spacing, This is the pure water reference spacing built into the system.

[0020] Furthermore, in step S4, the specific representation of the lower triangular decoupling matrix equation is as follows:

[0021] ;

[0022] in, The nickel ion concentration is [value missing]. The zinc ion concentration is [value missing]. , , These are the preset feature decoupling coefficients. , These are the baseline parameters for the bottom liquid.

[0023] Furthermore, in step S4, the specific logic of the multi-parameter simultaneous decoupling calculation is as follows: An independent solution formula is constructed using the first row of the matrix equation: The nickel ion concentration can be solved independently. The calculated nickel ion concentration Substituting the known parameters into the second row of the matrix equation, the refractive index superposition model: In the process, the zinc ion concentration is calculated. .

[0024] Further, in step S1, the wavelength of the feature measurement light source is set to 720 nm, corresponding to the characteristic absorption peak band of the nickel ion complex; the wavelength of the reference baseline light source is set to 900 nm, corresponding to the non-absorption background band of nickel and zinc ions.

[0025] To address the aforementioned technical problems, a second aspect of the present invention provides an automatic monitoring device for the content of nickel-zinc ions in electroplating, used to execute the automatic monitoring and identification method for the content of nickel-zinc ions in electroplating described in the first aspect, the device comprising:

[0026] A flow detection unit is configured in the bypass circulation pipeline of the main electroplating tank for constant flow guidance of the liquid to be tested. The flow detection unit is equipped with a background calibration target.

[0027] A composite light source module is arranged on the front light side of the flow detection unit and is used to emit transmitted light of different wavelengths to the flow detection unit.

[0028] A highly robust imaging module is arranged on the backlight side of the flow detection unit and is used to acquire data of transmitted images through the flow detection unit.

[0029] The control and computing unit is communicatively connected to the composite light source module and the highly robust imaging module, and is used to output a timing synchronization trigger signal and run a multi-parameter simultaneous decoupling algorithm.

[0030] Furthermore, the composite light source module is a dual-wavelength LED array, including a feature measurement light source emitting a 720nm wavelength and a reference baseline light source emitting a 900nm wavelength; the high-robust imaging module includes a global shutter monochrome industrial camera.

[0031] Furthermore, an orthogonal polarization optical path is configured between the composite light source module and the high-robust imaging module. The orthogonal polarization optical path includes mutually orthogonal polarizers respectively installed in front of the dual-wavelength LED array and in front of the global shutter monochrome industrial camera lens.

[0032] Furthermore, the main body of the flow detection unit is a flat rectangular flow channel made of quartz glass, and the outside of the flow detection unit is covered with a water bath temperature control jacket; the background calibration target is a micron-sized black and white striped grating etched on the backlight side surface of the flow detection unit using photolithography.

[0033] Compared with the prior art, the present invention has the following beneficial effects:

[0034] (1) Achieving simultaneous quantitative identification of colored and colorless ions in mixed solutions: This invention constructs a detection architecture based on characteristic transmission spectra and background grating distortion shift. Utilizing the physical properties of colored ions having characteristic absorption peaks and colorless ions altering the fluid's refractive index, and combining this with a lower triangular decoupling matrix model, it achieves decoupled calculation of the concentration of colorless zinc ions in the mixed solution. This scheme requires no chemical pretreatment and provides a non-contact, multi-dimensional quantitative detection method.

[0035] (2) Suppressing fluid dynamic interference and improving the robustness of detection results: To address the problem of light intensity attenuation caused by bubbles, particles, and fluctuations in the turbidity of the base solution in the circulation pipeline of the electroplating production line, this invention introduces a time-division multiplexing acquisition mechanism for the characteristic measurement wavelength and the reference baseline wavelength. By utilizing the correlation between the reference wavelength and the characteristic wavelength in terms of physical scattering characteristics, non-component light attenuation interference is suppressed through ratio calculation, reducing the requirements of optical detection on fluid clarity and improving measurement stability under complex working conditions.

[0036] (3) Optimize the hardware stability configuration to improve detection repeatability and extend the maintenance cycle: By configuring orthogonal polarization elements in the optical path system, the specular reflection interference at the flow channel interface is suppressed, and the signal-to-noise ratio of background grating distortion feature extraction is improved; combined with the thermodynamic constraint of the water bath temperature control jacket, the refractive index thermal drift caused by ambient temperature fluctuations is reduced. The overall device structure is reliable, which helps to reduce the long-term drift of the detection signal and reduce the frequency of manual calibration and maintenance. Attached Figure Description

[0037] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, 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 the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0038] Figure 1 This is a flowchart of an automatic monitoring and identification method for nickel-zinc ion content in electroplating according to an embodiment of the present invention;

[0039] Figure 2 This is a schematic diagram of the structure and optical path principle of the automatic monitoring device for nickel-zinc ion content in electroplating in an embodiment of the present invention;

[0040] Figure 3 This is a hardware timing diagram for multimodal image synchronous acquisition in an embodiment of the present invention;

[0041] Figure 4 This is a logic block diagram of the multi-parameter simultaneous decoupling algorithm in an embodiment of the present invention.

[0042] Among them, 100 is the flow detection unit; 110 is the water bath temperature control jacket; 120 is the background calibration target; 200 is the composite light source module; 210 is the feature measurement light source; 220 is the reference baseline light source; 230 is the polarizer; 300 is the high robustness imaging module; 310 is the global shutter monochrome industrial camera; 320 is the analyzer; 400 is the control and computing unit; 500 is the main electroplating tank; 510 is the bypass circulation pipeline; and 520 is the corrosion-resistant circulation pump. Detailed Implementation

[0043] To make the objectives, technical solutions, and advantages of this application clearer, the following detailed description is provided in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the scope of this application. All other embodiments obtained by those skilled in the art based on the embodiments of this application without inventive effort are protected by this application.

[0044] It should be noted that the terms "comprising," "including," and "having," and any variations thereof, in the specification, claims, and accompanying drawings of this application, are intended to cover non-exclusive inclusion. For example, a process, method, terminal, product, or device that includes a series of steps or units is not limited to the listed steps or units, but may optionally include steps or units not listed, or may optionally include other steps or units inherent to these processes, methods, products, or devices. Terms such as "first" and "second" in the claims, specification, and accompanying drawings of this application, as well as relational terms, are used merely to distinguish one entity / operation / object from another entity / operation / object, and do not necessarily require or imply any such immediate relationship or order between these entities / operations / objects.

[0045] In this document, the term "embodiment" means that a particular feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment of this application. The appearance of this phrase in various places throughout the specification does not necessarily refer to the same embodiment, nor is it a mutually exclusive, independent, or alternative embodiment. It will be explicitly and implicitly understood by those skilled in the art that the embodiments described herein can be combined with other embodiments.

[0046] Nickel-zinc alloy electroplating is widely used in the electroplating manufacturing of precision hardware, automotive parts, and electronic connectors. During nickel-zinc alloy electroplating, the ratio of nickel to zinc in the plating layer directly determines the corrosion resistance and ductility of the final product. Therefore, accurately monitoring and controlling the concentration and ratio of nickel and zinc ions in the electroplating solution is crucial. An imbalance in ion concentration can easily lead to a decrease in the corrosion resistance of the entire batch of electroplated products or cause the plating layer to crack and peel off. Existing electroplating solution ion content detection technologies have the following significant technical shortcomings:

[0047] Firstly, chemical titration suffers from significant time lag and is prone to secondary pollution: Currently, most production lines rely on manual sampling or automated titrators (such as EDTA complexometric titration) for chemical analysis. This traditional method takes 15 to 30 minutes per test, resulting in severe detection lag, which cannot meet the dynamic requirements of high-speed continuous electroplating production lines for real-time online replenishment of chemicals. In addition, the titration process continuously consumes a large amount of chemical reagents, inevitably generating difficult-to-treat secondary waste liquid, resulting in high environmental protection and compliance costs.

[0048] Secondly, contact electrochemical sensors are highly susceptible to contamination, leading to signal drift or even failure. Some production lines have attempted to use ion-selective electrodes (ISEs) directly immersed in electroplating tanks or pipelines for online detection. However, electroplating solutions contain high concentrations of organic additives (such as brighteners and carriers) and active metal ions. These substances readily undergo physical adsorption, chemical passivation, or reduction reactions on the sensor probe surface, causing rapid probe contamination and severe thermal drift and baseline shift in the detection signal. This necessitates frequent shutdowns for manual cleaning and recalibration, resulting in extremely high maintenance costs and difficulty in guaranteeing long-term robustness.

[0049] Third, traditional optical and visual technologies are ill-suited to complex working conditions and suffer from a blind spot in colorless ion perception: conventional UV-Vis spectrophotometers are only suitable for ideal, static, and clear laboratory measurement conditions. However, in the circulating pipelines of electroplating production lines, microbubbles, variations in the turbidity of the substrate, and drastic temperature fluctuations are unavoidable. These fluid interference factors cause drastic and random attenuation of transmitted light intensity, completely masking the true absorbance differences caused by changes in ion concentration. Even more critically, while nickel ions have significant absorption peaks in specific wavelength ranges, zinc ions are colorless and transparent in the visible to near-infrared range. This renders traditional machine vision or single-dimensional spectroscopy techniques completely incapable of directly capturing and quantitatively identifying the visual characteristics of zinc ions in mixed solutions.

[0050] In view of this, embodiments of this application provide an automatic monitoring device and identification method for the content of nickel-zinc ions in electroplating. On the one hand, by constructing a detection architecture based on characteristic transmission spectra and background grating distortion displacement, and utilizing the physical properties of colored ions having characteristic absorption peaks while colorless ions change the refractive index of the fluid, combined with a lower triangular decoupling matrix model, synchronous decoupled quantitative identification of the concentrations of colored ions and colorless zinc ions in the mixed solution is achieved. On the other hand, a time-division multiplexing acquisition mechanism of characteristic measurement wavelength and reference baseline wavelength is introduced. Through ratio calculation, non-component light attenuation interference caused by bubbles, fluctuations in bottom liquid turbidity, etc., is suppressed, improving the robustness of the detection results under complex industrial conditions. Furthermore, by configuring a hardware-stabilized configuration of orthogonal polarization elements and a water bath temperature control jacket, specular reflection interference at the flow channel interface is suppressed and thermal drift of the refractive index is reduced, which is beneficial to improving the repeatability of detection and extending the maintenance cycle of the device.

[0051] To illustrate the technical solution of this application, specific embodiments are described below.

[0052] Please refer to Figure 1 , Figure 3 and Figure 4 This application provides an automatic monitoring and identification method for the content of nickel and zinc ions in electroplated metals. Specifically, the automatic monitoring and identification method may include the following steps S1 to S4.

[0053] Step S1, Multimodal Image Synchronous Acquisition: Under the trigger of the control and computing unit, The feature measurement light source in the composite light source module is constantly illuminated, and the highly robust imaging module exposes and acquires feature transmission images; The reference baseline light source in the composite light source module is constantly illuminated, and the high-robust imaging module exposes and acquires the background grating distortion image.

[0054] Among them, such as Figure 3 As shown in the high-frequency timing diagram, the control and calculation unit outputs microsecond-level pulse timing. At that time, the wavelength of the characteristic measurement light source was set to 720 nm, which corresponds to the characteristic absorption peak band of nickel ion complexes, while zinc ions show no absorption here; At any given time, the wavelength of the reference baseline light source was set to 900 nm, which is a background band with no absorption for nickel and zinc ions. By alternately illuminating the two sets of light sources and simultaneously exposing the highly robust imaging module, the system acquired multimodal optical image data under the same physical state within an extremely short time window.

[0055] Step S2, Anti-interference image preprocessing: The pixel grayscale value correction is calculated for the feature transmission image and the background grating distortion image respectively using the flat field correction algorithm to obtain the corrected feature transmission image and the corrected background grating distortion image.

[0056] Among them, such as Figure 4 As shown in the algorithm logic diagram, under industrial field conditions, long-term operation of the light source will cause light attenuation, and the inherent vignetting effect of the lens will lead to uneven imaging illumination. By introducing the flat-field correction algorithm, the true transmission information can be restored. The specific formula for calculating pixel grayscale value correction is as follows:

[0057] ;

[0058] in, The pixel grayscale values ​​are those of the original acquired feature transmission image or the background raster distortion image. The pixel grayscale value of the dark field image of the high-robust imaging module. To calibrate the pixel grayscale values ​​of a brightfield image for pure water, This refers to the grayscale values ​​of the pixels in the corrected output image.

[0059] Step S3, Physical Feature Extraction and Mapping: Extract the average gray values ​​of the corrected feature transmission image and the corrected background grating distortion image in the region of interest, and extract the turbidity relative absorbance by calculating the logarithmic ratio of the corresponding wavelength; use a sub-pixel edge detection operator to locate the current stripe spacing of the background calibration target in the corrected background grating distortion image, and perform a differential comparison with the pure water reference spacing to extract the visual sub-pixel offset.

[0060] Among them, the relative absorbance for turbidity removal was extracted. The specific formula is:

[0061] ;

[0062] in, The average gray value of the corrected feature transmission image in the region of interest. The value represents the average grayscale value of the corrected background grating distortion image within the region of interest. Since the stray light attenuation caused by bubbles and turbidity has a highly consistent effect on wavelengths of 720nm and 900nm, a division operation can automatically filter out global intensity attenuation interference caused by turbidity fluctuations at the bottom layer, preserving pure concentration absorption characteristics. Simultaneously, for the background grating distortion image, the visual sub-pixel offset is extracted. The specific formula is:

[0063] ;

[0064] in, For the current stripe spacing, This is the system's built-in pure water reference spacing. This feature physically characterizes the amount of optical path deflection caused by the overall change in the solution's refractive index.

[0065] Step S4: Multi-parameter simultaneous decoupling calculation: Based on the principle of single-variable correlation of absorbance and linear superposition of multiple variables of refractive index, construct a lower triangular decoupling matrix equation. Independently solve the nickel ion concentration by combining the first row of the lower triangular decoupling matrix equation with the relative absorbance of turbidity. Substitute the nickel ion concentration into the second row of the lower triangular decoupling matrix equation and solve the zinc ion concentration by combining the visual sub-pixel offset, and output the comprehensive judgment result.

[0066] The specific representation of the lower triangular decoupling matrix equation is as follows:

[0067] .

[0068] in, The nickel ion concentration is [value missing]. The zinc ion concentration is [value missing]. , , These are the preset feature decoupling coefficients. , These are the baseline parameters for the bottom liquid.

[0069] The specific logic of the multi-parameter simultaneous decoupled calculation is as follows: According to the extension of Lambert-Beer's law, absorbance is only related to colored nickel ions. Therefore, an independent solution formula is constructed using the first row of the matrix equation: The nickel ion concentration can be solved independently. ;

[0070] The overall refractive index of the solution (represented by the visual subpixel offset) is contributed linearly by the base solution, nickel ions, and zinc ions. The system will solve for... Substituting the known parameters into the second row of the matrix equation, the refractive index superposition model: In this way, the concentration of colorless and transparent zinc ions, which cannot be directly obtained visually or spectrally, can be stably solved. Ultimately, the system outputs a comprehensive judgment result that includes the concentration of nickel ions, the concentration of zinc ions, and their alloy control ratios.

[0071] The beneficial effects of this application embodiment compared with the prior art are as follows: It achieves simultaneous quantitative identification of colored ions and colorless ions in a mixed solution: This invention constructs a detection architecture based on characteristic transmission spectra and background grating distortion shift, utilizing the physical properties of colored ions having characteristic absorption peaks while colorless ions change the refractive index of the fluid, and combining this with a lower triangular decoupling matrix model to achieve decoupled calculation of the concentration of colorless zinc ions in the mixed solution. This scheme requires no chemical pretreatment and provides a non-contact, multi-dimensional quantitative detection method; it suppresses fluid dynamic interference and improves the robustness of the detection results: Addressing the problem of light intensity attenuation caused by bubbles, particles, and fluctuations in the turbidity of the base solution in the circulation pipeline of the electroplating production line, this invention introduces a time-division multiplexing acquisition mechanism for the characteristic measurement wavelength and the reference baseline wavelength. By leveraging the correlation between the reference wavelength and the characteristic wavelength in terms of physical scattering characteristics, non-component optical attenuation interference is suppressed through ratio calculations, reducing the requirements for fluid clarity in optical detection and improving measurement stability under complex working conditions. Optimized hardware stabilization configuration improves detection repeatability and extends maintenance cycles: by configuring orthogonal polarization elements in the optical path system, specular reflection interference at the flow channel interface is suppressed, improving the signal-to-noise ratio for background grating distortion feature extraction; and the thermodynamic constraint of the water bath temperature control jacket reduces refractive index thermal drift caused by ambient temperature fluctuations. The overall device structure is reliable, which helps reduce long-term drift of the detection signal and reduces the frequency of manual calibration and maintenance.

[0072] Please refer to Figure 2 This application provides an automatic monitoring device for the content of nickel and zinc ions in electroplated metals.

[0073] Specifically, the apparatus for performing the above-described automatic monitoring and identification method includes:

[0074] A flow detection unit 100 is configured in the bypass circulation pipeline 510 of the main electroplating tank 500 for constant flow guidance of the liquid to be tested. A background calibration target 120 is configured inside the flow detection unit 100.

[0075] A composite light source module 200 is arranged on the front light side of the flow detection unit 100 and is used to emit transmitted light of different wavelengths to the flow detection unit 100.

[0076] A highly robust imaging module 300 is arranged on the backlight side of the flow detection unit 100 and is used to acquire data of transmitted images through the flow detection unit 100.

[0077] The control and computing unit 400 is communicatively connected to the composite light source module 200 and the high-robust imaging module 300, and is used to output a timing synchronization trigger signal and run a multi-parameter simultaneous decoupling algorithm.

[0078] In this embodiment, combined with Figure 2 The optical path principle and fluid structure shown indicate that the electroplating solution is continuously drawn from the main electroplating tank 500 by the anti-corrosion circulation pump 520, flows continuously from bottom to top through the core flow detection unit 100 via the bypass circulation pipeline 510, completes optical detection, and then flows back to the main electroplating tank 500 in a closed loop, achieving 24-hour uninterrupted non-destructive online monitoring. To eliminate the thermal drift phenomenon caused by the refractive index of the liquid due to ambient temperature fluctuations, the main body of the flow detection unit 100 is made of a flat rectangular flow channel made of quartz glass material resistant to strong acids and alkalis, and is externally covered by a water bath temperature control jacket 110 to apply extremely strict thermodynamic constraints. The background calibration target 120 is a micron-level black and white striped grating etched on the backlight side surface of the flow detection unit 100 using a high-precision photolithography process.

[0079] The composite light source module 200 is a high-frequency response dual-wavelength LED array, including an independently controlled feature measurement light source 210 emitting a 720nm wavelength and a reference baseline light source 220 emitting a 900nm wavelength; the high robust imaging module 300 includes a global shutter monochrome industrial camera 310 for eliminating dynamic motion blur caused by rapid fluid flow.

[0080] Furthermore, to improve the optical signal-to-noise ratio under harsh operating conditions, an orthogonal polarization optical path is configured between the composite light source module 200 and the high-robust imaging module 300. This orthogonal polarization optical path specifically includes a polarizer 230 mounted in front of the dual-wavelength LED array and an analyzer 320 mounted in front of the lens of the global shutter monochrome industrial camera 310, with their polarization directions being orthogonal to each other. This hardware architecture completely eliminates specular reflection from the quartz cell wall interface and external stray light interference through the orthogonal polarization principle, ensuring that the camera target surface only receives pure transmitted distorted light passing through the liquid under test, greatly improving the robustness of the detection and the maintenance-free cycle of the device.

[0081] The above embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit it. 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. These 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 automatically monitoring and identifying the content of nickel and zinc ions in electroplated metal, characterized in that, Includes the following steps: Step S1, Multimodal Image Synchronous Acquisition: Under the trigger of the control and computing unit, The feature measurement light source in the composite light source module is constantly illuminated, and the highly robust imaging module exposes and acquires feature transmission images; The reference baseline light source in the composite light source module is constantly illuminated, and the high-robust imaging module exposes and acquires a background raster distortion image. Step S2, Anti-interference image preprocessing: The pixel grayscale value correction is calculated for the feature transmission image and the background grating distortion image respectively using the flat field correction algorithm to obtain the corrected feature transmission image and the corrected background grating distortion image; Step S3, Physical Feature Extraction and Mapping: Extract the average gray values ​​of the corrected feature transmission image and the corrected background grating distortion image in the region of interest, and extract the turbidity relative absorbance by calculating the logarithmic ratio of the corresponding wavelength; use a sub-pixel edge detection operator to locate the current stripe spacing of the background calibration target in the corrected background grating distortion image, and perform a differential comparison with the pure water reference spacing to extract the visual sub-pixel offset; Step S4: Multi-parameter simultaneous decoupling calculation: Based on the principle of single-variable correlation of absorbance and linear superposition of multiple variables of refractive index, construct a lower triangular decoupling matrix equation. Independently solve the nickel ion concentration by combining the first row of the lower triangular decoupling matrix equation with the relative absorbance of turbidity. Substitute the nickel ion concentration into the second row of the lower triangular decoupling matrix equation and solve the zinc ion concentration by combining the visual sub-pixel offset, and output the comprehensive judgment result.

2. The automatic monitoring and identification method for nickel-zinc ion content in electroplating according to claim 1, characterized in that, In step S1, the wavelength of the characteristic measurement light source is set to 720 nm, corresponding to the characteristic absorption peak band of the nickel ion complex; the wavelength of the reference baseline light source is set to 900 nm, corresponding to the non-absorption background band of nickel and zinc ions.

3. The automatic monitoring and identification method for nickel-zinc ion content in electroplating according to claim 2, characterized in that, In step S2, the specific formula for calculating pixel grayscale value correction using the flat-field correction algorithm is as follows: ； in, The pixel grayscale values ​​are those of the original acquired feature transmission image or the background raster distortion image. The pixel grayscale value of the dark field image of the high-robust imaging module. To calibrate the pixel grayscale values ​​of a brightfield image for pure water, This refers to the grayscale values ​​of the pixels in the corrected output image.

4. The automatic monitoring and identification method for nickel-zinc ion content in electroplating according to claim 3, characterized in that, In step S3, the turbidity-reduced relative absorbance is extracted. The specific formula is: ； in, The average gray value of the corrected feature transmission image in the region of interest. The average grayscale value of the corrected background raster distortion image in the region of interest; extract the visual subpixel offset. The specific formula is: ； in, For the current stripe spacing, This is the pure water reference spacing built into the system.

5. The automatic monitoring and identification method for nickel-zinc ion content in electroplating according to claim 4, characterized in that, In step S4, the specific representation of the lower triangular decoupling matrix equation is as follows: ； in, The nickel ion concentration is [value missing]. The zinc ion concentration is [value missing]. , , These are the preset feature decoupling coefficients. , These are the baseline parameters for the bottom liquid.

6. The automatic monitoring and identification method for nickel-zinc ion content in electroplating according to claim 5, characterized in that, The specific logic of the multi-parameter simultaneous decoupled calculation is as follows: An independent solution formula is constructed using the first row of the matrix equation: The nickel ion concentration can be solved independently. The calculated nickel ion concentration Substituting the known parameters into the second row of the matrix equation, the refractive index superposition model: In the process, the zinc ion concentration is calculated. .

7. An automatic monitoring device for nickel-zinc ion content in electroplating, characterized in that, The method for automatically monitoring and identifying the content of nickel-zinc ions in electroplating as described in any one of claims 1 to 6 includes: A flow detection unit is configured in the bypass circulation pipeline of the main electroplating tank for constant flow guidance of the liquid to be tested. The flow detection unit is equipped with a background calibration target. A composite light source module is arranged on the front light side of the flow detection unit and is used to emit transmitted light of different wavelengths to the flow detection unit. A highly robust imaging module is arranged on the backlight side of the flow detection unit and is used to acquire data of transmitted images through the flow detection unit. The control and computing unit is communicatively connected to the composite light source module and the highly robust imaging module, and is used to output a timing synchronization trigger signal and run a multi-parameter simultaneous decoupling algorithm.

8. The automatic monitoring device for nickel-zinc ion content in electroplating according to claim 7, characterized in that, The composite light source module is a dual-wavelength LED array, including a feature measurement light source emitting a 720nm wavelength and a reference baseline light source emitting a 900nm wavelength; the high-robust imaging module includes a global shutter monochrome industrial camera.

9. The automatic monitoring device for nickel-zinc ion content in electroplating according to claim 8, characterized in that, An orthogonal polarization optical path is configured between the composite light source module and the high-robust imaging module; the orthogonal polarization optical path specifically includes mutually orthogonal polarizers respectively installed in front of the dual-wavelength LED array and in front of the lens of the global shutter monochrome industrial camera.

10. The automatic monitoring device for nickel-zinc ion content in electroplating according to claim 7, characterized in that, The main body of the flow detection unit is a flat rectangular flow channel made of quartz glass, and the outside of the flow detection unit is covered with a water bath temperature control jacket; the background calibration target is a micron-sized black and white striped grating etched on the backlight side surface of the flow detection unit using photolithography.

Images