Automobile part electroplated layer thickness online monitoring and compensating method and system based on current self-adaptive adjustment

Abstract

The invention discloses an on-line monitoring and compensating method and system for the thickness of an electroplated layer of an automobile part based on current self-adaptive adjustment, and relates to the technical field of automation and intelligent control. Correcting the original thickness data according to the deviation degree between the current temperature and the real-time PH value and the preset reference data to obtain the real coating thickness of each subarea under the reference condition, judging that the real coating thickness reaches the standard according to the preset trigger compensation condition, if the real coating thickness reaches the standard, continuously monitoring on line, and if the real coating thickness does not reach the standard, determining the current increment of each subarea. According to the method, the current increment is compensated according to the influence of the PH value deviation, the reference current is adjusted, the final adjustment current is output, and the plating thickness of each subarea is dynamically compensated, so that the multi-dimensional process variable can be sensed, and the plating thickness of each subarea can be dynamically compensated by dynamically adjusting the current and compensating the thickness deviation caused by parameter fluctuation. And finally, the whole-course accurate control of the coating thickness of the automobile part is realized.

Description

Technical Field

[0001] This invention relates to the field of automation and intelligent control technology, specifically to a method and system for online monitoring and compensation of electroplating thickness of automotive parts based on adaptive current adjustment. Background Technology

[0002] The thickness of the electroplated coating on automotive parts (such as wheel hubs, gears, and chassis bolts) is a core indicator determining their corrosion resistance, wear resistance, and appearance quality. With the automotive industry's continuously increasing demands for component reliability, the traditional offline sampling inspection method (sampling and thickness measurement after electroplating) is no longer sufficient to meet real-time quality control requirements. This not only easily leads to batches of defective products but also results in poor coating thickness consistency due to fluctuations in process parameters (such as changes in temperature and pH), time decay (metal ion consumption), and spatial differences (uneven deposition at the edges / center of complex-shaped parts).

[0003] Existing technologies for controlling the electroplating thickness of automotive parts have the following core defects: First, existing technologies mostly compensate for a single parameter, failing to incorporate the coupled effects of key variables such as temperature and pH into the thickness correction logic. Compensation for a single parameter can lead to thickness correction results deviating from reality, ultimately resulting in a mismatch between the compensation current and the actual deposition rate, causing the coating thickness to exceed or fall short of the standard. Furthermore, thickness measurements often directly use raw data without correcting for measurement deviations caused by temperature and pH fluctuations. In particular, existing systems do not dynamically allocate current to different areas, resulting in poor thickness consistency across different parts of the component, making it difficult to meet the quality requirements of complex-shaped parts. During the electroplating process, as time progresses, the consumption of metal ions and passivation of the electrode surface cause the deposition rate to gradually decrease, but existing technologies do not correct for this time-related decay. Summary of the Invention

[0004] The purpose of this invention is to provide a method and system for online monitoring and compensation of electroplating thickness of automotive parts based on adaptive current adjustment, which solves the problems mentioned in the background art.

[0005] In a first aspect, one embodiment of the present invention provides a method for online monitoring and compensation of electroplating thickness of automotive parts based on adaptive current adjustment, the method comprising the following steps: Collect raw thickness data and process parameters during the electroplating process of automotive parts. The raw thickness data is the raw plating thickness of each zone of the parts. The process parameters include the current temperature of the electroplating tank, the real-time pH value of the electroplating solution, the current electroplating time, and the electroplating start time. Based on the deviation between the current temperature and the real-time pH value and the preset reference data, and in combination with the preset first influence coefficient and second influence coefficient, the original thickness data is corrected to obtain the true coating thickness of each zone under the reference conditions. The reference data includes reference electroplating temperature, reference electroplating solution pH value, and reference current and target coating thickness for each zone. Based on the pre-set trigger compensation conditions including thickness, temperature, pH value and time factors, determine whether the actual coating thickness of each zone meets the standard. If it meets the standard, continue to monitor online. If the standard is not met, the current increment of each zone is determined based on the relative deviation between the actual coating thickness and the original coating thickness, the coupling attenuation coefficient obtained under time and temperature coupling calculation, and the regional weight coefficient of each zone. Then, based on the compensation for the current increment caused by the pH value deviation, the reference current is adjusted to obtain the final adjustment current for each zone; The final adjustment current is output, and the coating thickness of each zone is dynamically compensated.

[0006] Optionally, the raw thickness data is acquired using an online eddy current thickness gauge; The current temperature is acquired via a temperature sensor; The real-time pH value is acquired via an online pH sensor; The current electroplating duration and the electroplating start time are collected by the PLC's built-in timer.

[0007] Optionally, the specific method for correcting the original thickness data is as follows: The temperature correction factor is obtained by multiplying the first difference between the current temperature and the reference electroplating temperature with the first influence coefficient. The pH correction factor is obtained by multiplying the absolute value of the deviation between the real-time pH value and the pH value of the reference electroplating solution with the second influence coefficient. The original coating thickness of each partition is multiplied sequentially by the temperature correction factor and the pH correction factor to obtain the actual coating thickness of each partition under the baseline conditions. Wherein, the first influence coefficient is the preset influence coefficient of temperature on the deposition rate; The second influence coefficient is the attenuation coefficient of the deposition rate by the preset pH value.

[0008] Optionally, the specific method for determining the current increment is as follows: The relative thickness deviation is obtained based on the relative deviation between the actual coating thickness and the original coating thickness; Based on the second difference between the current electroplating duration and the electroplating start time, and combined with the time decay coefficient corresponding to the electroplating duration, a time decay sub-factor is obtained. Then, based on the product of the time decay sub-factor and the temperature correction factor, a composite correction factor is obtained. The current increment for each partition is determined by multiplying the regional weight coefficient of each partition of the component with the reference current and the composite correction factor.

[0009] Optionally, the specific method for the final adjustment current and closed-loop feedback is as follows: Multiply the current increment by the pH correction factor and add it to the reference current to obtain the final adjustment current; The final adjustment current is output to each zone through a zoned DC rectifier; Data is collected, thickness is corrected, and current is calculated every 5-10 minutes to dynamically compensate for fluctuations in process parameters.

[0010] Optionally, the triggering compensation conditions include: The deviation between the actual coating thickness and the target coating thickness did not exceed the preset thickness threshold. The deviation between the current temperature and the reference electroplating temperature does not exceed the preset temperature threshold. The deviation between the real-time pH value and the pH value of the reference electroplating solution did not exceed the preset pH threshold. The deviation between the current electroplating duration and the electroplating start time does not exceed the preset duration threshold. If all of the above standards are met, no compensation is required, and continuous online monitoring will be conducted.

[0011] Secondly, embodiments of the present invention also provide an online monitoring and compensation system for the thickness of electroplated coatings on automotive parts based on adaptive current adjustment, including a memory, a processor, and a computer program stored in the memory and running on the processor, wherein the processor executes the computer program to implement the method provided in the first aspect of the embodiments above.

[0012] Optionally, the processor also includes a partitioned DC rectifier for outputting differentiated adjusted current to each partition of the component.

[0013] Compared with the prior art, the beneficial effects of the present invention are as follows: I. This invention eliminates the interference of parameter fluctuations on thickness measurement by quantitatively correcting the coupled effects of temperature and pH value. When the temperature rises and the deposition rate increases, the system will combine the degree of pH value deviation from the benchmark (such as the rate decay caused by low pH) to make equivalent corrections to the original thickness data. This not only solves the deviation problem of single parameter compensation in the prior art, but also makes the thickness monitoring results closer to the actual deposition state.

[0014] Second, this invention introduces spatial weight logic to assign differentiated compensation weights to different areas of automotive parts (such as edges, centers, and concave-convex structures). For example, the wheel hub edge is prone to being too thick due to high current density, so the system will reduce the compensation weight of this area; the center area is prone to being insufficient, so the weight will be increased. This solves the problem of uneven regional distribution caused by the overall adjustment in the prior art and ensures that the thickness of each part of the complex-shaped parts meets the standard.

[0015] Third, this invention combines the time decay effect with the temperature effect and dynamically adjusts the compensation range. When the rate decays due to the consumption of metal ions in the later stage of electroplating, the system will correct the compensation current according to the cumulative time (reduce the adjustment range), and at the same time combine the temperature change (such as the temperature rise to offset part of the decay), thereby solving the problem of ignoring the time decay in the prior art and ensuring the stability of the deposition rate throughout the process.

[0016] Thus, this invention establishes a closed-loop control logic of "monitoring → correction → compensation → re-monitoring", continuously collecting data to update correction factors, ensuring that the compensation strategy always adapts to the process status. In addition, online real-time monitoring and compensation reduce the time cost of offline sampling inspection and avoid the generation of batches of non-conforming products. Attached Figure Description

[0017] Figure 1 This is a flowchart of the online monitoring and compensation method for the electroplating thickness of automotive parts based on adaptive current adjustment, according to the present invention. Detailed Implementation

[0018] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0019] Please see Figure 1 The diagram illustrates a flowchart of an embodiment of the present invention for an online monitoring and compensation method for the thickness of electroplated coatings on automotive parts based on adaptive current adjustment. The method includes the following steps: Step S001: Collect the original thickness data and process parameters of the automotive parts during the electroplating process. The original thickness data is the original plating thickness of each zone of the parts. The process parameters include the current temperature of the electroplating tank, the real-time pH value of the electroplating solution, the current electroplating time, and the electroplating start time.

[0020] Preferably, in one embodiment of this application, an online eddy current thickness gauge is used to collect the original coating thickness of each zone on the surface of the component in real time. For example, for a car wheel hub, its surface can be divided into several regions such as the edge, center, and corners, and an eddy current thickness sensor is installed in each region to collect data once per second; The current temperature is collected in real time by a temperature sensor installed in the electroplating tank, with a sampling frequency of once per second. Real-time pH values ​​are collected by an online pH sensor immersed in the electroplating solution and are updated once per second. The current electroplating duration and start time are recorded by a high-precision timer built into the main control PLC of the electroplating production line. The timer starts automatically when electroplating begins and continues to accumulate the current process running time.

[0021] It is understandable that the synchronous acquisition of raw thickness data and various process parameters is the foundation for achieving subsequent accurate correction and compensation. All sensor data is uploaded to the central processing unit in real time via industrial Ethernet or fieldbus, forming a continuous data stream with timestamps. The above is only for reference regarding the acquisition frequency of each device. The specific acquisition frequency needs to be set according to the actual use. This setting is existing technology and will not be elaborated further.

[0022] Thus, key process parameters such as the original coating thickness, current temperature, real-time pH value, and current electroplating time of each zone during the electroplating process were obtained.

[0023] Step S002: Based on the deviation between the current temperature and real-time pH value and the preset reference data, and combined with the preset first influence coefficient and second influence coefficient, the original thickness data is corrected to obtain the true coating thickness of each zone under the reference conditions.

[0024] The specific method for correcting the original thickness data is as follows: The temperature correction factor is obtained by multiplying the first difference between the current temperature and the reference electroplating temperature with the first influence coefficient. The pH correction factor is obtained by multiplying the absolute value of the deviation between the real-time pH value and the pH value of the reference electroplating solution with the second influence coefficient. The original coating thickness of each zone is multiplied sequentially by the temperature correction factor and the pH correction factor to obtain the true coating thickness of each zone under the baseline conditions. The formula for calculating the true coating thickness of zone i is as follows: ; In the formula: d corr,i For the corrected actual coating thickness of region i (i=1 (edge), 2 (center), 3 (corner)), d raw,iFor the original coating thickness of region i measured in real time by the zoned X-ray thickness gauge, IF T The first influence coefficient of temperature on current efficiency is given by T, where T is the current temperature of the electroplating bath, T0 is the reference electroplating temperature, and IF is the current efficiency coefficient. PH PH is the second influence coefficient on the deposition rate, where PH is the real-time pH value of the electroplating solution and PH0 is the pH value of the reference electroplating solution.

[0025] Preferably, in one embodiment of this application, the reference data is pre-stored in the system database, including: reference electroplating temperature T0, reference electroplating solution pH value PH0, and reference current I for each zone. base and the target coating thickness d target .

[0026] First Influence Coefficient IF T The coefficient representing the effect of temperature on current efficiency is the second influence coefficient, IF. PH This represents the attenuation coefficient of the deposition rate due to pH value. Both coefficients were obtained through previous experimental calibration, the specific calibration method of which is as follows: First Influence Coefficient IF T Calibration: Electroplating experiments were conducted at different temperatures (e.g., 20℃, 25℃, 30℃, etc.) with fixed parameters such as pH, current, and time. The coating thickness was measured at various temperatures, and the rate of change of current efficiency Δη / ΔT for every 1°C change in temperature was calculated. This rate of change is the first influence coefficient IF. T (If a 1°C increase in temperature leads to a 1% increase in current efficiency, then the first influence coefficient IF) T =0.01), where Δη / ΔT is the change in current efficiency of metal deposition current before and after temperature change (Δη=η2-η1, where η is the ratio of actual deposition amount to theoretical deposition amount), and ΔT is the temperature change between two different temperatures in the calibration experiment (ΔT=T2-T1, such as ΔT=5℃ when 25℃→30℃). Second Influence Coefficient IF PH Calibration: Electroplating experiments were conducted at different pH values ​​(such as 5.0, 5.5, 6.0, etc.) with fixed parameters such as temperature, current, and time. The deposition rate was measured at various pH values, and the percentage decrease in deposition rate Δv / ΔPH for every 1 unit deviation of pH from the baseline was calculated. This percentage is the second influence coefficient IF. PH (If the pH deviates by 1 unit, the deposition rate decreases by 2%, then the second influence coefficient IF) PH =0.02), where Δv / ΔPH is the change in deposition rate after PH deviates from the baseline value (Δv=v0−v). i v0 is the rate at the reference pH, v i(the rate after deviation), and ΔPH is the absolute value of the deviation of PH from the reference value.

[0027] It can be understood that The correction formula of quantifies the coupling effect of temperature and PH. Specifically, electroplating is an electrochemical reaction process. As the temperature increases, the thermal motion of metal ions in the electroplating solution intensifies, the migration speed accelerates, and the concentration polarization (the phenomenon that the ion concentration on the electrode surface is lower than that in the bulk solution) is reduced. After the concentration polarization decreases, more current is used for the reduction and deposition of metal ions (instead of side reactions such as hydrogen evolution), and the current efficiency increases accordingly. The original coating thickness d in region i raw,i does not consider the gain of temperature on the current efficiency. Therefore, the true thickness needs to be multiplied by the first influence coefficient IF T Amplification: When the current temperature T > the reference electroplating temperature T0, the deposition rate accelerates, and the original coating thickness d in region i raw,i will be on the high side and is multiplied by a factor greater than 1 ( ) for equivalent "reduction". On the contrary, if the current temperature T < the reference electroplating temperature T0, then After correction, the thickness shrinks (in line with the law that the current efficiency decreases at low temperatures).

[0028] The PH value is the core chemical parameter of the electroplating solution. If the PH is too low (too acidic), more current will be used for hydrogen evolution, reducing the effective current for metal deposition; if the PH is too high (too alkaline), metal ions are prone to hydrolysis to form hydroxide precipitates, covering the electrode surface and hindering deposition; whether the PH is too high or too low, the reduction rate of metal ions will be reduced, and the deposition rate (coating thickness per unit time) will decrease accordingly. The original coating thickness d in region i raw,i does not consider the negative impact of PH deviation. Therefore, it needs to be multiplied by to shrink, where The absolute value result of can ensure that the deviation direction does not affect the correction effect, After multiplication, the true coating thickness d in region i corr,i < the original coating thickness d in region i raw,i , reflecting the thickness reduction caused by the decrease in the deposition rate.

[0029] In addition, in an industrial electroplating system, when the current temperature T exceeds the process upper limit (such as > 60 °C), it will cause the electroplating solution to decompose, the electrode to passivate, the coating to be rough, or even the electroplating solution to boil (posing a safety hazard). Based on this, when the current temperature T > the upper limit temperature T max (such as 65 °C), the relay linkage cuts off the heating power supply or the entire electroplating circuit, and at the same time gives an alarm to prompt the operator; and when the deviation range of the real-time PH value PH is too large (such as the real-time PH value < 4 or the real-time PH value > 7), it will cause poor coating adhesion, many pinholes, or even corrosion of the equipment (too acidic to corrode the tank body). Therefore, when the real-time PH value < the minimum PH value PHmin Or real-time pH value > highest pH value max If this occurs, the system will immediately stop the electroplating operation and activate an alarm (audio-visual or SMS) to prevent the production of defective products or equipment damage.

[0030] Therefore, the thickness measured under actual fluctuating operating conditions is uniformly corrected to the "true" thickness under the reference conditions (reference plating temperature T0, reference plating solution pH value PH0) - the true coating thickness d of region i. corr,i This provides an accurate basis for subsequent judgments and compensation.

[0031] Thus, the actual coating thickness d of region i in each partition was obtained under the baseline process conditions. corr,i .

[0032] Step S003: Based on the preset trigger compensation conditions including thickness, temperature, pH value and time factors, determine whether the actual coating thickness of each zone meets the standard. If it meets the standard, continue online monitoring.

[0033] The conditions that trigger compensation include: The deviation between the actual coating thickness and the target coating thickness did not exceed the preset thickness threshold. Thickness threshold, such as 0.1 μm; The deviation between the current temperature and the reference electroplating temperature does not exceed the preset temperature threshold. Temperature threshold, such as ±1℃; The deviation between the real-time pH value and the pH value of the reference electroplating solution did not exceed the preset pH threshold. pH threshold, such as ±0.2; The deviation between the current electroplating duration and the electroplating start time does not exceed the preset duration threshold. Duration threshold, such as 5 minutes; If all of the above standards are met, no compensation is required, and continuous online monitoring will be conducted.

[0034] Preferably, in one embodiment of this application, the system checks in real time whether all partitions simultaneously meet the above four conditions. If all partitions meet all conditions, the current electroplating process is determined to be in an ideal state, and no current compensation is required. The system will then continue to execute steps S001 and S002 for continuous online monitoring.

[0035] Understandably, setting multi-dimensional trigger conditions avoids frequent or unnecessary compensation actions caused by fluctuations in a single parameter. The compensation process is only initiated when there is a significant deviation in any dimension—thickness, temperature, pH, or time—thus improving the stability and economy of system control. For each trigger condition, firstly, the process has a clear tolerance for product thickness, as long as… The deviation is within the specified range, and the product already meets quality standards. Forcibly triggering compensation would lead to frequent current adjustments, increasing system control complexity, and could even cause new deviations (such as excessive thickness) due to over-adjustment, thus disrupting process stability. Secondly, When the deviation is extremely small (e.g., ±0.2), its effect on the deposition rate is negligible; then, When the deviation is ±1℃, the changes in the migration rate and reactivity of metal ions are minimal. This change can be covered by the natural fluctuations during the electroplating process and no additional compensation is required. Finally, in the early stage of electroplating (such as the first 5 minutes), the metal ions are consumed very little, and no obvious passivation film has been formed on the electrode surface. The deposition rate is almost unaffected. At this time, triggering compensation (such as time correction factor) is not only ineffective, but may also lead to excessive current adjustment, which may destroy the uniformity of the initial deposition (such as excessive thickness at the edges). Therefore, triggering is not necessary.

[0036] This completes the dynamic determination of whether compensation needs to be initiated.

[0037] Step S004: If the standard is not met, determine the current increment of each zone based on the relative deviation between the actual coating thickness and the original coating thickness, the coupling attenuation coefficient obtained under time and temperature coupling calculation, and the regional weight coefficient of each zone.

[0038] Preferably, in one embodiment of this application, when any partition does not meet any condition of step S003, the system initiates compensation calculation. First, the coupling attenuation coefficient EAF between time and temperature is calculated. t : Based on the second difference between the current electroplating time and the electroplating start time, and combined with the time decay coefficient corresponding to the electroplating time, a time decay sub-factor is obtained. Then, by multiplying the time decay sub-factor by the temperature correction factor, a composite correction factor is obtained. The specific calculation formula is as follows: ; In the formula: EAF t The coupling decay coefficient between time and temperature is given. The increase in electroplating time leads to two decay effects: ① The concentration of metal ions in the electroplating solution decreases (due to deposition and consumption). ② Electrode surface passivation (forming an oxide film that hinders electron transfer). Ultimately, this causes the deposition rate to decay over time, EAF t Coupling attenuation coefficient EAF as time-temperature compensation t Its function is to increase the current adjustment amplitude with time, and to decay over time. ) and temperature rise ( These are independent proportional effects; multiplying them combines their effects (e.g., time decay increases the rate by 0.8 times, temperature increase increases the rate by 1.2 times, resulting in a combined rate of 0.8 × 1.2 = 0.96 times, close to the original rate), ensuring the coupling decay coefficient EAF. t It can precisely offset rate decay, IF t The time decay factor is IF. t It was also obtained through experimental calibration, and the steps are as follows: Fixed process parameters (temperature, pH, current density, etc.); Electroplating start time t0 (deposition rate per unit time thickness increase). Measure the rate v1 at regular time intervals (e.g., t1 = t0 + 10 min); Calculate the attenuation ratio: ; The time decay coefficient IF is obtained by fitting multiple sets of data (such as t2, t3). t (such as time decay factor IF) t =0.005 / min, indicating that the rate decreases by 0.5% for every 1 minute increase; t is the current electroplating duration, and t0 is the electroplating start time; Next, calculate the current increment for each partition: The relative thickness deviation is obtained based on the relative deviation between the actual coating thickness and the original coating thickness. Based on the product of the regional weighting coefficient of each partition of the component and the reference current and composite correction factor, the formula for calculating the current increment of each partition is as follows: ; In the formula: △I i For the current increment of region i that needs to be adjusted, I base d is the reference current for the current region. target Target coating thickness; The result is the relative thickness deviation. A positive value indicates that the thickness is insufficient and the current needs to be increased, while a negative value indicates that the thickness is too large and the current needs to be decreased. w i The regional weighting coefficient (e.g., edge w1=1.2 / center w2=0.9, areas with high current density require a larger adjustment range) is preset based on the geometry of the part and the current density distribution, and differentiated compensation for different areas is achieved through weight adjustment.

[0039] It is understandable that the current increment ΔI in region i i The calculation incorporates thickness deviation, time decay effect, temperature influence, and spatial differences, with a coupled decay coefficient EAF. tThis allows the compensation amount to be dynamically adjusted according to the process (the compensation amplitude decreases in the later stages due to attenuation), and the regional weighting coefficient w i This ensures that each part of the complex component receives the appropriate compensation focus.

[0040] At this point, the required current increment ΔI in region i for each zone to achieve the thickness target has been calculated. i .

[0041] In step S005, the reference current is adjusted according to the compensation for the current increment caused by the pH value deviation, so as to obtain the final adjustment current for each zone.

[0042] Preferably, in one embodiment of this application, since pH deviation directly affects deposition efficiency, after determining the initial current increment, a pH correction factor is needed to perform a secondary correction to obtain the final adjusted current. The calculation formula for the final adjusted current is as follows: ; In the formula: I adj,i The current is finally adjusted for region i.

[0043] in, Compensation for thickness deviation, time, and temperature has been considered, but the effect of pH deviation has not been covered. Multiply by the factor ( After that, it's equivalent to adjusting the current to adapt to the rate requirement after pH decay, and This is the pH correction factor used in step S002. When the pH deviates from the reference, this factor ( The value is less than 1, thus affecting the current increment ΔI in region i. i The reduction is made because the actual thickness increase that the same current increment can bring will be reduced due to the adverse effects of pH.

[0044] Understandably, this step refines the compensation strategy. It ensures that even under unfavorable pH conditions, the system's output current adjustment command is based on an accurate prediction of the actual deposition efficiency, avoiding "overcompensation" or "undercompensation," and making the control more closely aligned with the complexities of the process.

[0045] At this point, the final adjustment current I for region i, which has taken into account the effects of all key process variables, has been obtained for each partition in the next control cycle. adj,i .

[0046] Step S006: Output the final adjustment current and dynamically compensate for the coating thickness of each zone.

[0047] Preferably, in one embodiment of this application, the central processing unit will ultimately adjust the current I of each partition's region i.adj,i The command is sent to the partitioned DC rectifier via digital communication. This rectifier has multiple independently controllable output channels, each corresponding to a partition of the component, and can output different current values ​​simultaneously.

[0048] After receiving the command, the rectifier immediately changes the current in each zone from the original reference current I. base Adjust to region i and finally adjust the current I adj,i Simultaneously, the system initiates a new monitoring-calculation cycle. The preferred cycle time is 5-10 minutes. That is, after the current is adjusted and stabilized for 5-10 minutes, the system automatically returns to step S001, re-collects the latest thickness, temperature, and pH data, executes the correction, judgment, and calculation process again, and generates a new current adjustment command based on the latest process status.

[0049] Understandably, this step achieves closed-loop control. The system doesn't end after a single adjustment, but continuously "monitor → correct → judge → compensate → re-monitor," forming a dynamic adaptive adjustment loop. This allows for real-time tracking and compensation for slow drifts or sudden disturbances in various parameters during the electroplating process, ensuring that the thickness of each zone steadily converges towards the target value throughout the entire electroplating process.

[0050] Thus, a complete control cycle for online monitoring and compensation of electroplating thickness of automotive parts based on adaptive current adjustment was completed, and a sustainable closed-loop control system was established.

[0051] Based on the same inventive concept as the above method, this embodiment of the invention also provides an online monitoring and compensation system for the thickness of electroplated coatings on automotive parts based on adaptive current adjustment, including a memory, a processor, and a computer program stored in the memory and running on the processor. When the processor executes the computer program, it implements steps S001-S006.

[0052] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A method for online monitoring and compensation of electroplating thickness of automotive parts based on adaptive current adjustment, characterized in that, The method includes the following steps: Collect raw thickness data and process parameters during the electroplating process of automotive parts. The raw thickness data is the raw plating thickness of each zone of the parts. The process parameters include the current temperature of the electroplating tank, the real-time pH value of the electroplating solution, the current electroplating time, and the electroplating start time. Based on the deviation between the current temperature and the real-time pH value and the preset reference data, and in combination with the preset first influence coefficient and second influence coefficient, the original thickness data is corrected to obtain the true coating thickness of each zone under the reference conditions. The reference data includes reference electroplating temperature, reference electroplating solution pH value, and reference current and target coating thickness for each zone. Based on the pre-set trigger compensation conditions including thickness, temperature, pH value and time factors, determine whether the actual coating thickness of each zone meets the standard. If it meets the standard, continue to monitor online. If the standard is not met, the current increment of each zone is determined based on the relative deviation between the actual coating thickness and the original coating thickness, the coupling attenuation coefficient obtained under time and temperature coupling calculation, and the regional weight coefficient of each zone. Then, based on the compensation for the current increment caused by the pH value deviation, the reference current is adjusted to obtain the final adjustment current for each zone; The final adjustment current is output, and the coating thickness of each zone is dynamically compensated.

2. The method for online monitoring and compensation of electroplating thickness of automotive parts based on adaptive current adjustment according to claim 1, characterized in that, The original thickness data was acquired using an online eddy current thickness gauge. The current temperature is acquired via a temperature sensor; The real-time pH value is acquired via an online pH sensor; The current electroplating duration and the electroplating start time are collected by the PLC's built-in timer.

3. The method for online monitoring and compensation of electroplating thickness of automotive parts based on adaptive current adjustment according to claim 2, characterized in that, The specific method for correcting the original thickness data is as follows: The temperature correction factor is obtained by multiplying the first difference between the current temperature and the reference electroplating temperature with the first influence coefficient. The pH correction factor is obtained by multiplying the absolute value of the deviation between the real-time pH value and the pH value of the reference electroplating solution with the second influence coefficient. The original coating thickness of each partition is multiplied sequentially by the temperature correction factor and the pH correction factor to obtain the true coating thickness of each partition under the baseline conditions. Wherein, the first influence coefficient is the preset influence coefficient of temperature on the deposition rate; The second influence coefficient is the attenuation coefficient of the deposition rate by the preset pH value.

4. The method for online monitoring and compensation of electroplating thickness of automotive parts based on adaptive current adjustment according to claim 3, characterized in that, The specific method for determining the current increment is as follows: The relative thickness deviation is obtained based on the relative deviation between the actual coating thickness and the original coating thickness; Based on the second difference between the current electroplating duration and the electroplating start time, and combined with the time decay coefficient corresponding to the electroplating duration, a time decay sub-factor is obtained. Then, based on the product of the time decay sub-factor and the temperature correction factor, a composite correction factor is obtained. The current increment for each partition is determined by multiplying the regional weight coefficient of each partition of the component with the reference current and the composite correction factor.

5. The method for online monitoring and compensation of electroplating thickness of automotive parts based on adaptive current adjustment according to claim 4, characterized in that, The specific methods for the final adjustment current and closed-loop feedback are as follows: Multiply the current increment by the pH correction factor and add it to the reference current to obtain the final adjustment current; The final adjustment current is output to each zone through a zoned DC rectifier; Data is collected, thickness is corrected, and current is calculated every 5-10 minutes to dynamically compensate for fluctuations in process parameters.

6. The method for online monitoring and compensation of electroplating thickness of automotive parts based on adaptive current adjustment according to claim 1, characterized in that, The triggering compensation conditions include: The deviation between the actual coating thickness and the target coating thickness did not exceed the preset thickness threshold. The deviation between the current temperature and the reference electroplating temperature does not exceed the preset temperature threshold. The deviation between the real-time pH value and the pH value of the reference electroplating solution did not exceed the preset pH threshold. The deviation between the current electroplating duration and the electroplating start time does not exceed the preset duration threshold. If all of the above standards are met, no compensation is required, and continuous online monitoring will be conducted.

7. An online monitoring and compensation system for the thickness of electroplated coatings on automotive parts based on adaptive current adjustment, comprising a memory, a processor, and a computer program stored in the memory and running on the processor, characterized in that, When the processor executes the computer program, it implements the steps of the method as claimed in any one of claims 1-6.

8. The online monitoring and compensation system for electroplating thickness of automotive parts based on adaptive current adjustment according to claim 7, characterized in that, The processor also includes a partitioned DC rectifier for outputting differentiated adjustable current to each partition of the component.

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