Conducting strip pressing force control method suitable for automobile connector and related device

Abstract

The invention relates to a conducting strip pressing force control method suitable for an automobile connector and a related device, and the method comprises the steps: obtaining motor current data and motor position data, generating a first force estimation value and a second force estimation value through a first calculation path and a second calculation path, calculating the instantaneous deviation of the first force estimation value and the second force estimation value in real time, and transmitting the instantaneous deviation into a fast feedback loop and a slow feedback loop; the fast feedback loop generates a short-term correction value to dynamically compensate the first force estimation value; the slow feedback loop accumulates the instantaneous deviation to generate a long-term drift distance, and when the long-term drift distance meets a preset aging judgment condition, self-adaptive updating of a reference force-displacement model or a first calculation path is triggered; and outputting the dynamically compensated first force estimation value as a final pressing force control instruction. According to the invention, while high-resolution dynamic response is realized, short-term drift can be corrected through a stable reference, and the reference has self-adaptive capability so as to compensate long-term drift caused by equipment aging.

Description

Methods and related devices for controlling the clamping force of conductive sheets in automotive connectors Technical Field

[0001] This application relates to the field of industrial manufacturing, and in particular to a method and apparatus for controlling the clamping force of conductive sheets in automotive connectors. Background Technology

[0002] In the manufacturing process of precision components such as automotive connectors, especially in processes involving the punching or assembly of conductive sheets, applying precise clamping force to the components is a critical process requirement. For example, in order to protect the plating on the surface of the conductive sheet from being damaged by pressure, the clamping assembly needs to apply an appropriate and stable force that is sufficient to stabilize the workpiece while avoiding pressure overload.

[0003] To achieve this force control, using servo motor components is a common technical solution. A straightforward approach is to install high-precision force sensors to form a closed loop. However, in conditions like mold making where there is high-frequency vibration and temperature variation, the physical sensors themselves are prone to damage, and their measurement signals may drift over time, leading to insufficient reliability in long-term applications.

[0004] Therefore, the industry tends to adopt a more indirect control method, which estimates the output force by monitoring the drive current of the servo motor. This method utilizes the strong correlation between motor current and output torque, has a fast response speed, and does not require fragile external sensors.

[0005] Nevertheless, this current-based estimation method faces a technical challenge in practical applications. The conversion relationship between motor current and actual output force is not constant. First, as the equipment continues to operate, the heating of the motor coils causes changes in its resistance characteristics, which can lead to a short-term temperature rise drift in the force estimation value. Second, the transmission mechanisms in servo components, such as ball screws or gears, undergo irreversible mechanical wear over prolonged use, resulting in a slow but continuous change in the system's frictional characteristics.

[0006] This estimation drift, caused by both heat and wear, gradually renders the conversion coefficients set during the initial equipment calibration ineffective. A system calibrated in a cold state may no longer produce accurate estimates after several hours of operation. After several months of operation, the cumulative error due to mechanical aging may cause the actual output clamping force to deviate significantly from process requirements, thereby increasing the risk of product coating damage and affecting the stability and consistency of long-cycle production. Summary of the Invention

[0007] In order to achieve high-resolution dynamic response using current signals, correct short-term drift using a stable reference, and enable the reference itself to have self-adaptive capabilities to compensate for long-term drift caused by equipment aging, this application provides a conductive sheet clamping force control method and related device suitable for automotive connectors.

[0008] Firstly, this application provides a method for controlling the clamping force of conductive sheets in automotive connectors, employing the following technical solution: A method for controlling the clamping force of conductive sheets in automotive connectors includes the following steps: S1. Real-time acquisition of motor current data and motor position data of a servo clamping assembly; S2. Based on the motor current data, generating a first force estimation value through a first calculation path; S3. Based on a preset reference force-displacement model and the motor position data, generating a second force estimation value through a second calculation path; S4. Real-time calculation of the force estimation value and the second force estimation value. S5. The instantaneous deviation is fed into at least one fast feedback loop, which generates a short-term correction and uses the short-term correction to dynamically compensate the first force estimate; S6. The instantaneous deviation is fed into at least one slow feedback loop, which accumulates the instantaneous deviation to generate a long-term drift, and when the long-term drift meets a preset aging judgment condition, it triggers an adaptive update of the reference force-displacement model or the first calculation path; S7. The dynamically compensated first force estimate is output as the final clamping force control command.

[0009] Optionally, step S1 further includes a preprocessing step: the acquired motor current data and motor position data are filtered by a rate of change limiter before being sent to S2 and S3 to remove instantaneous spike data caused by electrical interference or encoder jumps, and a fail-safe mode is triggered when the data fails continuously.

[0010] Optionally, the sub-step of S2 includes: S21. Calculating a dynamic compensation current required to overcome the inertia of the motor and mechanical load based on the second derivative of the motor position data and a preset system inertia model; S22. Subtracting the dynamic compensation current from the motor current data to obtain a quasi-static current; S23. Multiplying the quasi-static current by a preset current-force conversion coefficient to generate a preliminary force estimate; S24. Processing the preliminary force estimate through a low-pass filter to eliminate instantaneous high-frequency fluctuations caused by current sampling noise, and outputting the filtered result as the first force estimate.

[0011] Optionally, the sub-step of S3 includes: S31. Obtaining real-time system operating condition parameters, wherein the real-time system operating condition parameters are used to characterize the current operating state of the mold or the properties of the processed material; S32. Using the real-time system operating condition parameters, querying a preset reference force-displacement model to retrieve one or more basic force-displacement curves associated with the real-time system operating condition; S33. When multiple basic force-displacement curves are retrieved, performing inter-model interpolation or fusion processing on the multiple basic force-displacement curves according to the closeness between the real-time system operating condition and the corresponding operating conditions of the multiple basic force-displacement curves to generate a transient force-displacement curve specifically for the current operating condition; S34. Performing model interpolation calculation on the transient force-displacement curve based on the motor position data to determine and output the second force estimation value.

[0012] Optionally, the sub-step of S4 includes: S41. Subtracting the second force estimation value from the first force estimation value to calculate an initial deviation value; S42. Comparing the absolute value of the initial deviation value with a preset insensitive area threshold; when the absolute value of the initial deviation value is less than the insensitive area threshold, forcing the instantaneous deviation to be defined as zero; when the absolute value of the initial deviation value is greater than or equal to the insensitive area threshold, outputting the initial deviation value as the instantaneous deviation.

[0013] Optionally, the sub-step of S5 includes: S51. Using the instantaneous deviation as a control input signal of the fast feedback loop; S52. In the fast feedback loop, applying a preset proportional algorithm to calculate a proportional correction component based on the current amplitude of the instantaneous deviation; S53. In the fast feedback loop, applying a preset integral algorithm to calculate an integral correction component based on the accumulation of the instantaneous deviation over time, to eliminate steady-state drift, wherein the steady-state drift may be caused by motor temperature rise; S54. Superimposing the proportional correction component and the integral correction component to generate a short-term correction amount; S55. Arithmetically applying the short-term correction amount to the first force estimate in real time to complete dynamic compensation, thereby obtaining a force estimate that is calibrated in real time.

[0014] Optionally, the sub-step of S6 includes: S61. Feeding the instantaneous deviation into a time-weighted integrator of the slow feedback loop, wherein the time-weighted integrator is used to accumulate the instantaneous deviation for a preset period to generate the long-term drift; S62. Monitoring the long-term drift output by the time-weighted integrator and continuously comparing it with a preset aging threshold; wherein the aging threshold is used to characterize irreversible mechanical wear; S63. Setting an aging confirmation period, wherein the aging confirmation period is multiple consecutive working cycles or a preset number of operating hours; S64. When the long-term drift is continuously greater than the aging threshold within the aging confirmation period, the aging judgment condition is confirmed to be met; when the aging judgment condition is met, calculating the model correction amount based on the long-term drift amount, and using the model correction amount, performing adaptive updates on the conversion coefficients of the first calculation path or the data of the reference force-displacement model.

[0015] Optionally, the sub-step of S7 includes: S71. Real-time monitoring of the current operating stage of the servo pressing component to determine whether the driver of the servo pressing component should be in position control mode or force control mode; S72. When the servo pressing component is in the rapid approach operating stage, keeping the driver of the servo pressing component in the position control mode; S73. When the motor position data of the servo pressing component reaches a preset force / position switching coordinate, switching the driver of the servo pressing component to the force control mode; S74. In the force control mode, sending the dynamically compensated first force estimation value as the target setting value to the internal torque control loop of the driver of the servo pressing component in real time; S75. The internal torque control loop of the driver of the servo pressing component automatically adjusts the output current according to the deviation between the target setting value and the actual motor current, so that the actual output clamping force of the servo pressing component tracks the dynamically compensated first force estimation value.

[0016] Secondly, this application provides a computer device that adopts the following technical solution: a computer device comprising: one or more processors; a memory; one or more application programs, wherein the one or more application programs are stored in the memory and configured to be executed by the one or more processors, and the one or more programs are configured to: execute the above-described conductive sheet clamping force control method for automotive connectors.

[0017] Thirdly, the computer-readable storage medium provided in this application adopts the following technical solution: a computer-readable storage medium storing a computer program that can be loaded by a processor and execute the above-described methods.

[0018] The storage medium stores at least one instruction, at least one program, code set, or instruction set, which is loaded and executed by the processor to implement the conductive sheet clamping force control method for automotive connectors as described above.

[0019] In summary, this application includes at least one of the following beneficial technical effects: 1. By acquiring data through two calculation paths and using dual feedback loops to handle short-term disturbances and long-term aging respectively, the final output clamping force control command integrates the high dynamic characteristics of the first calculation path and the reference stability of the second calculation path, thus possessing both high dynamic response characteristics and accuracy in long-term operation; 2. By sending the instantaneous deviation into a slow feedback loop to accumulate and generate long-term drift, and triggering an adaptive update of the reference force-displacement model or the first calculation path when the aging judgment condition is met, the correction of the reference system itself is realized, overcoming the long-term failure problem caused by mechanical wear or changes in friction characteristics; 3. By generating a first force estimate based on motor current and a second force estimate based on the position model at each same time, and using the short-term correction amount generated by the fast feedback loop to perform dynamic compensation on the first force estimate, real-time correction of short-term drift caused by, for example, motor temperature rise or electrical noise is realized, ensuring high resolution and short-term stability of the output command. Attached Figure Description

[0020] Figure 1 illustrates a schematic diagram of pressing and cutting a metal strip inside a mold in one embodiment of the present invention.

[0021] Figure 2 illustrates a flowchart of a conductive sheet clamping force control method applicable to automotive connectors according to an embodiment of the present invention.

[0022] Reference numerals: 1. Punch; 2. Fixed die blank; 3. Conductive sheet; 4. Moving die blank; 5. Punching gap. Detailed Implementation

[0023] The present application will be further described in detail below with reference to the accompanying drawings. It should be understood that the specific embodiments described herein are merely illustrative of the application and are not intended to limit the scope of the application.

[0024] In the following description, numerous specific details are set forth for purposes of explanation in order to provide a thorough understanding of the inventive concept. As part of this specification, some of the accompanying drawings of this disclosure are block diagrams illustrating structures and devices to avoid complicating the disclosed principles. For clarity, not all features of the actual embodiment need to be described. Furthermore, the language used in this disclosure has been primarily chosen for readability and instructional purposes and may not have been chosen to define or limit the subject matter of the invention, thus requiring the necessary claims to determine such inventive subject matter. References to “an embodiment” or “an embodiment” in this disclosure mean that a particular feature, structure, or characteristic described in connection with that embodiment is included in at least one embodiment, and multiple references to “an embodiment” or “an embodiment” should not be construed as necessarily referring to the same embodiment.

[0025] Unless explicitly defined, the terms “a,” “an,” and “the” are not intended to refer to a singular entity, but rather to include a general category whose specific examples can be used for illustration. Therefore, the use of the terms “a” or “an” can mean any number of at least one, including “a,” “one or more,” “at least one,” and “one or more.” The term “or” means any of the options and any combination of the options, including all options unless explicitly indicated that the options are mutually exclusive. The phrase “at least one of” when combined with a list of items refers to a single item in the list or any combination of items in the list. The phrase does not require all items listed unless explicitly defined as such.

[0026] This application relates to a method for controlling the clamping force of conductive pads in automotive connectors. Automotive connectors are critical components used to transmit current and signals in automotive electrical systems. One of the core components of an automotive connector is the conductive pad, also commonly referred to as a terminal. This conductive pad is typically stamped from a metal material, and its surface often has a plating layer, such as a tin layer, to ensure good electrical contact and corrosion resistance.

[0027] The production of conductive sheets typically involves complex composite processes, such as those performed in injection-stamping hybrid molds. This process may include punching, bending, and cutting a metal strip within the mold, followed by or simultaneously injection molding the metal part. This process integrates stamping and injection molding within a single mold, and the equipment used is called a composite mold, which integrates a punch for cutting and a clamping assembly for fixing. Figure 1 illustrates an embodiment of the clamping and cutting station in this composite mold. As shown in Figure 1, the structure includes a punch 1, a fixed mold clamping assembly 2, a conductive sheet 3, a moving mold clamping assembly 4, and a cutting gap 5. Before cutting, the fixed mold clamping assembly 2 and the moving mold clamping assembly 4, i.e., the servo clamping assembly described herein, first descend and clamp the conductive sheet 3. Subsequently, the punch 1 descends and, through engagement with the cutting edge of the moving mold clamping assembly 4, cuts the conductive sheet 3 at the cutting gap 5.

[0028] In the aforementioned composite process, clamping force control is crucial to yield. Before the punch performs the cutting action, the servo clamping assembly must first apply a precise clamping force to the conductive sheet. If the clamping force is insufficient, the conductive sheet will experience micron-level displacement or vibration under the impact of the punching force, resulting in decreased cutting accuracy, burrs on the cross-section, or dimensional deviations. Conversely, if the clamping force is too large, it will cause irreversible pressure or scratches on the plating layer on the conductive sheet surface, such as the tin layer, which will affect the electrical contact performance of the connector.

[0029] Currently, methods for achieving such precise clamping force control have limitations. One approach relies on the real-time current of a servo motor to estimate the clamping force. While this method offers a fast response, the servo motor's current signal is susceptible to temperature changes or electrical noise, causing the estimated force value to drift over a short period, resulting in cumulative errors. Another method relies on a static model based on the motor's position. Although this method provides a stable benchmark, it cannot adapt to changes in system characteristics caused by mechanical wear and increased friction during long-term operation. As the equipment ages, this static model becomes inaccurate, leading to control failure.

[0030] Therefore, this application provides a method for controlling the clamping force of conductive sheets in automotive connectors, referring to Figure 2, which includes the following steps S1-S7.

[0031] S1. Real-time acquisition of motor current and motor position data of the servo pressing component.

[0032] The servo clamping assembly is an actuator in the mold used to fix the conductive sheet before cutting. It typically consists of a servo motor, a ball screw and other transmission mechanisms, and a clamping head. Motor current data is acquired at high frequency by a current sensor inside the servo driver, for example, once every millisecond. Motor position data is obtained by a photoelectric encoder mounted on the servo motor shaft, providing high-precision position readings.

[0033] Motor current data and motor position data contain information from different dimensions for estimating the clamping force. Motor current data directly reflects the instantaneous torque output by the motor to overcome all resistances. It includes the actual clamping force applied to the conductive plate, the frictional force of the transmission mechanism, and the acceleration force required to overcome inertia. Therefore, current data is highly responsive and can capture instantaneous fluctuations in force. However, it is also susceptible to changes in winding resistance due to motor temperature rise or changes in frictional force due to changes in mechanical lubrication, causing the conversion relationship between current data and the actual clamping force to drift.

[0034] The motor position data accurately characterizes the physical stroke of the clamping assembly. This data exhibits high repeatability and stability. When the clamping assembly contacts the conductive sheet and begins compression, there is a relatively stable, calibrated physical mapping relationship between its position coordinates and the applied clamping force. In this method, motor current data serves as input to the first calculation path in S2, used to generate a high-resolution real-time estimate. Motor position data then serves as input to the second calculation path in S3, used to generate a stable reference value resistant to short-term drift.

[0035] Optionally, step S1 further includes a preprocessing step: the acquired motor current data and motor position data are filtered by a rate of change limiter before being sent to S2 and S3 to remove instantaneous spike data caused by electrical interference or encoder jumps, and a fail-safe mode is triggered when the data fails continuously.

[0036] Instantaneous spike data refers to brief but abnormally large data points caused by strong electrical interference or encoder signal fluctuations. If not removed, these spikes will be treated as real force or position changes by the calculation paths of S2 and S3, leading to erroneous instantaneous jumps in the first or second force estimate. These jumps contaminate the instantaneous deviation calculated by S4 and are amplified by the fast feedback loop of S5, ultimately causing unexpected pulses in the clamping force control command output by S7. This could momentarily damage the conductive sheet plating or cause system oscillations.

[0037] When data fails continuously, such as when the rate of change limiter is triggered in multiple consecutive control cycles, this indicates that the problem is no longer a transient disturbance, but rather a persistent fault in the sensor or its circuitry. In this case, a fail-safe mode must be triggered because continuing to use the confirmed continuously failing data for complex calculations in S2 to S7 will lead to unpredictable behavior of the entire adaptive force control loop, potentially causing mold damage or mass product scrapping. The fail-safe mode is a preset protective state. In this mode, the adaptive force control logic described in this method will immediately stop, the servo pressure component driver will stop executing the S7 command and may be forced back to a safe origin position. Simultaneously, the system will issue a high-level alarm to the operating interface, awaiting manual inspection and reset.

[0038] S2. Based on the motor current data, generate a first force estimate through a first calculation path.

[0039] The first force estimate is the force control signal used in this method for high dynamic response. It characterizes the actual clamping force applied to the conductive sheet by the servo clamping assembly at the current instant, as well as the sum of the forces required to overcome its own friction and inertia. Because it is derived directly from high-frequency sampled motor current data, it has high resolution and can sensitively track minute fluctuations in clamping force within milliseconds.

[0040] The first calculation path is an algorithm module whose core function is to perform the conversion from motor current to estimated force. Any algorithm capable of calculating the output force based on the electrical parameters and mechanical model of the servo motor can serve as the first calculation path. This path is characterized by its fast calculation speed and close tracking of instantaneous electrical signals, aiming to provide a high-dynamic-response base value for the final output of S7. However, the estimated value generated by this path is affected by the drift of the current data in S1.

[0041] Specifically, in one embodiment, the sub-steps of S2 include S21-S24.

[0042] S21. Based on the second derivative of the motor position data and the preset system inertia model, calculate a dynamic compensation current required to overcome the inertia of the motor and mechanical load.

[0043] S22. Subtract the dynamic compensation current from the motor current data to obtain a quasi-static current.

[0044] S23. Multiply the quasi-static current by a preset current-force conversion coefficient to generate a preliminary force estimate.

[0045] S24. The preliminary force estimate is processed through a low-pass filter to eliminate instantaneous high-frequency fluctuations caused by current sampling noise, and the filtered result is output as the first force estimate.

[0046] The calculation of the second derivative of the motor position data in S21 is to obtain the real-time acceleration of the servo pressure assembly. According to the laws of physics, a force is required to accelerate an object with mass. In a servo system, this force corresponds to the dynamic output torque of the motor, i.e., the dynamic compensation current. The system inertia model is a pre-calibrated parameter or function that characterizes the total equivalent mass of all moving parts of the servo pressure assembly, including the motor rotor, coupling, ball screw, and the pressure head itself. For example, the system inertia model can be defined as requiring 0.5A of dynamic current to generate an acceleration of 1m / s² for a pressure assembly weighing 2kg.

[0047] The subtraction operation in S22 is performed because the raw motor current data obtained in S1 is a mixed value containing multiple force components. The total current equals the dynamic compensation current required to overcome the system's inertia, plus the quasi-static current required to apply the actual clamping force and overcome mechanical friction. By subtracting the dynamic compensation current from the total current, step S22 decouples the two force components, resulting in the quasi-static current, which is the current component after eliminating the influence of acceleration. The physical meaning of this quasi-static current is that it characterizes the portion of the current used by the motor at the current moment only to apply static thrust and overcome friction, which is an effective signal for subsequent estimation of the clamping force.

[0048] The preset current-to-force conversion coefficient is a calibration value that converts the quasi-static current obtained in S22 into mechanical force. It is typically obtained during equipment commissioning by applying a known force using an external force sensor and then reversing the process to calibrate the required quasi-static current. This coefficient may vary in different scenarios; for example, motor temperature rise can cause changes in winding resistance, or mechanical wear can cause changes in friction, thus altering the accuracy of this coefficient. Therefore, different preset current-to-force conversion coefficients need to be used for different scenarios. Furthermore, this coefficient has a linear relationship with the initial force estimation.

[0049] Taking the clamping process of the conductive sheet in an automotive connector as an example, S21 acquires high-frequency position data and calculates the current acceleration of the clamping assembly as 0.2 m / s². The system inertia model determines that this acceleration requires a dynamic compensation current of 0.1 A. S22 obtains the total motor current data from the driver, which is 1.5 A. After subtracting 0.1 A, the quasi-static current is obtained as 1.4 A. S23 uses a preset conversion coefficient, such as 80 N / A, to multiply 1.4 A by this coefficient, generating a preliminary force estimate of 112 N. S24's low-pass filter then smooths this sequence value of 112 N, eliminating current sampling noise, and finally outputs a stable first force estimate, such as 111.9 N.

[0050] S3. Based on the preset reference force-displacement model and the motor position data, a second force estimate is generated through the second calculation path.

[0051] The preset reference force-displacement model is a database or function established during the equipment calibration phase. It describes the physical correspondence between the stroke position of the servo clamping assembly and the actual applied static clamping force. For example, this model might be a lookup table defining a clamping force of 50 N when the motor position data is 20.5 mm, and 60 N when the position data is 20.6 mm. This model is closely related to the motor position data, which is the primary input for querying this model.

[0052] The second force estimate serves as the benchmark anchor point for long-cycle calibration in this method. It characterizes the theoretical clamping force that the system should have in the calibration state at the current motor position. Since the motor position data is provided by the encoder, which has high stability and anti-drift characteristics, the second force estimate generated by S3 is not easily affected by short-term factors such as motor temperature rise and electrical noise. It represents a reliable benchmark free from cumulative errors.

[0053] The second calculation path is an algorithm module whose core function is to perform the conversion from motor position to estimated force. Any algorithm capable of outputting a force reference value based on position input and a calibration model can serve as the second calculation path. This path is characterized by high stability and repeatability of its results, aiming to provide a reliable calibration target for the feedback loops of S5 and S6.

[0054] Optionally, in one embodiment, the sub-steps of S3 include S31-S34.

[0055] S31. Obtain real-time system operating parameters, wherein the real-time system operating parameters are used to characterize the current operating state of the mold or the properties of the material being processed.

[0056] S32. Using the real-time system operating parameters, query the preset reference force-displacement model to retrieve one or more basic force-displacement curves associated with the real-time system operating conditions.

[0057] S33. When multiple basic force-displacement curves are retrieved, based on the degree of similarity between the real-time system operating condition and the corresponding operating conditions of the multiple basic force-displacement curves, inter-model interpolation or fusion processing is performed on the multiple basic force-displacement curves to generate a transient force-displacement curve specifically for the current operating condition.

[0058] S34. On the transient force-displacement curve, perform model interpolation calculation based on the motor position data to determine and output the second force estimate.

[0059] The real-time system operating parameters are selected according to the working environment of this embodiment. For example, in the processing of conductive sheets for automotive connectors, these parameters may be the thickness specification of the conductive sheet in the current production batch, or the real-time operating temperature of the mold. These parameters are typically determined by the equipment's control system based on the currently applied process formula. Different embodiments may employ different operating parameters.

[0060] In S32, the baseline force-displacement model is established for a set of discrete, calibrated operating points. If the real-time system operating parameters obtained in S31 fall between two calibrated operating points, the system will retrieve multiple basic force-displacement curves corresponding to these two calibrated operating points. For example, if the model calibrates two curves for 40°C and 80°C, and the real-time operating condition is 60°C, the system will simultaneously retrieve the basic force-displacement curves corresponding to 40°C and 80°C.

[0061] S33 determines the degree of similarity by calculating the relative distance between real-time operating parameters and calibration operating parameters. Taking 60°C as an example, the system determines that it is located between 40°C and 80°C, with a weight of 0.5 for each. Performing inter-model interpolation or fusion processing is to generate a transient force-displacement curve that accurately reflects the current 60°C operating condition, rather than simply applying any calibration curve. The fusion processing can use a weighted average algorithm to add the force values ​​at corresponding points on the two basic force-displacement curves according to their weights, generating the transient force-displacement curve.

[0062] S34 performs model interpolation calculations on the transient force-displacement curve generated in S33. The system takes the motor position data as input and searches on the coordinate axis of the transient curve. If the position data falls exactly between two adjacent position coordinate points in the curve database, the system performs linear interpolation to calculate the force value corresponding to that precise position and outputs it as a second force estimate.

[0063] Taking the conductive sheet clamping as an example, the real-time system operating condition obtained by S31 is a mold temperature of 60°C. S32 queries the model and retrieves curve A (corresponding to 40°C) and curve B (corresponding to 80°C). S33 determines the approximation of the 60°C operating condition to be 0.5 for each curve and generates a new transient force-displacement curve through weighted averaging. S34 obtains the motor position data from S1 as 20.55 mm. The system searches on the new transient curve and finds a force of 50 N at 20.5 mm and a force of 60 N at 20.6 mm. The system performs model interpolation calculations and finally determines the estimated value of the second force to be 55 N.

[0064] S4. Calculate the instantaneous deviation between the first force estimate and the second force estimate in real time.

[0065] S4 requires real-time calculations because it provides an immediate error signal to the fast feedback loop, a prerequisite for eliminating short-term drift. The execution frequency of the calculations can be matched with the data acquisition cycle of S1, for example, once every 1 ms or every 10 ms. This calculation cycle is typically much shorter than the total cycle time required for a complete pressing of the conductive sheet, for example, 200 ms. Therefore, the system can perform multiple S4 calculations within a single pressing cycle, ensuring high time resolution for the dynamic compensation of S5. Simultaneously, the interval between two calculations, for example, 1 ms, provides sufficient processing time for the controller to execute the operational logic of S4 through S7.

[0066] Optionally, in one embodiment, the sub-steps of S4 include S41-S44.

[0067] S41. Subtract the second force estimate from the first force estimate to calculate an original deviation value.

[0068] S42. Compare the absolute value of the original deviation value with a preset insensitive area threshold; when the absolute value of the original deviation value is less than the insensitive area threshold, force the instantaneous deviation to be defined as zero; when the absolute value of the original deviation value is greater than or equal to the insensitive area threshold, output the original deviation value as the instantaneous deviation.

[0069] S41 calculates the raw deviation value by subtracting the high-resolution first force estimate from the stable second force estimate. This raw deviation value quantifies the degree of deviation of the real-time calculated path from the reference anchor point path, reflecting short-term drift caused, for example, by motor temperature rise or electrical noise.

[0070] S42 introduces an insensitive zone threshold, which is a noise filtering mechanism. While the second force estimate generated in S3 is stable, it is based on model and interpolation calculations and may contain slight quantization noise or computational jitter. If the original deviation value calculated by S41 is very small, for example, below 0.2 N, and less than the preset insensitive zone threshold, S42 determines that the deviation is not a real system drift but meaningless computational noise. In this case, S42 forcibly defines the instantaneous deviation as zero to prevent the fast feedback loop of S5 from over-responding to this noise, thereby avoiding high-frequency oscillations in the subsequent output control commands near the stable point. Only when the original deviation value is greater than this threshold does S42 recognize the deviation as a real drift that needs to be corrected and output it as an instantaneous deviation to trigger the dynamic compensation of S5.

[0071] S5. The instantaneous deviation is fed into at least one fast feedback loop, which generates a short-term correction and uses the short-term correction to dynamically compensate for the first force estimate.

[0072] A fast feedback loop is a control algorithm module configured to respond quickly to instantaneous deviations. Its response time is typically set within several control cycles to match the frequency of short-term disturbances. Structurally, this fast feedback loop can be a proportional-integral-derivative (PID) controller or a proportional-integral (PI) controller.

[0073] The short-term correction is the operational output value of the fast feedback loop. Its function is to act as a compensation signal, applied in real-time to the first force estimate before the final command is output. This is to eliminate short-term drift in the first force estimate caused by reversible factors such as motor temperature rise or electrical noise, ensuring that it is pulled back to the stable reference provided by S3 in real-time during the dynamic response process.

[0074] The standard for generating short-term correction is a non-zero instantaneous deviation. Once the instantaneous deviation exceeds the threshold of the insensitive zone, the fast feedback loop is activated and, based on its internal control law, such as proportional and integral algorithms, continuously calculates and generates a short-term correction corresponding to the deviation based on the magnitude and duration of the instantaneous deviation.

[0075] Specifically, in one embodiment, the sub-steps of S5 include S51-S55.

[0076] S51. The instantaneous deviation is used as a control input signal for the fast feedback loop.

[0077] S52. In the fast feedback loop, a preset proportional algorithm is applied to calculate a proportional correction component based on the current magnitude of the instantaneous deviation.

[0078] S53. In the fast feedback loop, a preset integral algorithm is applied to calculate an integral correction component based on the accumulation of the instantaneous deviation over time, in order to eliminate steady-state drift, wherein the steady-state drift may be caused by motor temperature rise.

[0079] S54. The proportional correction component and the integral correction component are superimposed to generate a short-term correction amount.

[0080] S55. The short-term correction is arithmetically applied to the first force estimate in real time to complete dynamic compensation, thereby obtaining a force estimate that is calibrated in real time.

[0081] The preset proportional algorithm is a mathematical operation that multiplies the instantaneous deviation by a preset proportional gain coefficient Kp. The proportional correction component is obtained through this multiplication operation, and its magnitude is proportional to the current amplitude of the instantaneous deviation. The preset integral algorithm integrates the instantaneous deviation over time and then multiplies the accumulated result by a preset integral gain coefficient Ki. The integral correction component is obtained through this operation, and its magnitude is related to both the amplitude and duration of the instantaneous deviation.

[0082] Because proportional and integral corrections are complementary, they are superimposed in S54. The proportional correction component provides a rapid response to instantaneous deviations, but it may not completely eliminate the deviation, especially when the initial force estimate experiences a persistent steady-state drift due to motor temperature rise. The integral correction component, on the other hand, accumulates this steady-state drift, generating a gradually increasing correction value until the drift is completely offset. The short-term correction generated by the superposition of the two components thus combines the ability to respond quickly with the ability to eliminate steady-state errors.

[0083] The arithmetic application of S55 is typically a subtraction operation. If the first force estimate is higher than the second force estimate, the instantaneous deviation is positive, and the short-term correction generated by S54 is also positive. S55 subtracts this short-term correction from the first force estimate to bring it closer to the reference value.

[0084] Continuing with the example of conductive sheet clamping, S51 uses the instantaneous deviation calculated in S4, for example, 5.0 N, as the control input. S52 applies a proportional algorithm, assuming a proportional gain Kp of 0.4, to calculate the proportional correction component as 5.0 N × 0.4 = 2.0 N. S53 applies an integral algorithm, assuming the cumulative integral value of the instantaneous deviation is 12.0 N·s and the integral gain Ki is 0.1, to calculate the integral correction component as 12.0 N ⋅ s × 0.1 = 1.2 N. S54 combines the two to generate a short-term correction of 2.0 N + 1.2 N = 3.2 N. S55 obtains the first force estimate from S2, for example, 111.9 N, and subtracts the short-term correction of 3.2 N generated in S54 to obtain a real-time calibrated force estimate of 108.7 N.

[0085] S6. The instantaneous deviation is fed into at least one slow feedback loop, which accumulates the instantaneous deviation to generate a long-term drift, and when the long-term drift meets a preset aging judgment condition, an adaptive update of the reference force-displacement model or the first calculation path is triggered.

[0086] Specifically, in one embodiment, the sub-steps of S6 include S61-S64.

[0087] S61. The instantaneous deviation is fed into a time-weighted integrator of the slow feedback loop, wherein the time-weighted integrator is used to accumulate the instantaneous deviation for a preset period to generate the long-term drift.

[0088] S62. Monitor the long-term drift amount output by the time-weighted integrator and continuously compare it with a preset aging threshold; wherein the aging threshold is used to characterize irreversible mechanical wear.

[0089] S63. Set an aging confirmation cycle, wherein the aging confirmation cycle is a plurality of consecutive working cycles or a preset number of operating hours.

[0090] S64. When the long-term drift amount is continuously greater than the aging threshold during the aging confirmation period, the aging judgment condition is confirmed to be met. When the aging judgment condition is met, the model correction amount is calculated based on the long-term drift amount, and the conversion coefficient of the first calculation path or the data of the reference force-displacement model is adaptively updated using the model correction amount.

[0091] A slow feedback loop is an algorithmic module with a response rate much lower than that of a fast feedback loop. Its purpose is to smooth data over a long period, filtering out short-term fluctuations and noise in instantaneous deviations and extracting only the continuous, unidirectional deviation trend. Structurally, a slow feedback loop can be an integrator with a long integral time constant or a low-pass filter with a very low cutoff frequency. A time-weighted integrator is one implementation of this structure; it calculates the long-term mean of the deviation by accumulating or weighting the instantaneous deviation over a long period.

[0092] Long-term drift is the output value of the time-weighted integrator, and it is generated by the non-zero instantaneous deviation of S4 over a long period. The purpose of this long-term drift is to quantify the systematic and permanent deviation between the first and second calculation paths caused by irreversible physical changes, such as mechanical wear leading to changes in frictional characteristics.

[0093] Aging criteria are a set of logical rules used to trigger adaptive updates, defined by the aging threshold and the aging confirmation period. The preset aging threshold is a force value, such as 2 N, representing the maximum average deviation the system can tolerate due to mechanical wear. The aging confirmation period is a time span, such as 10,000 consecutive work cycles or 8 operating hours. The aging criteria are: when the long-term drift consistently exceeds the 2 N aging threshold within the 8-hour aging confirmation period, the confirmation condition is met.

[0094] The goal of adaptive updates depends on the diagnosis of the cause of aging. If the long-term drift is determined to be caused by the failure of the current-force conversion coefficient in S23 due to motor performance degradation or a stable increase in friction, the system needs to perform adaptive updates on this conversion coefficient in the first calculation path. If the long-term drift is determined to be caused by a permanent change in the position-force correspondence of the reference force-displacement model in S3 due to wear of the transmission mechanism, the system needs to perform adaptive updates on the data of the reference force-displacement model.

[0095] Continuing with the example of conductive sheet clamping, assuming the equipment has been running for six months, mechanical wear has led to increased friction. Although the fast feedback loop can eliminate short-term temperature drift, S4 continuously calculates an average instantaneous deviation of 2.5 N. The time-weighted integrator in S61 accumulates this 2.5 N deviation over a long period, generating a long-term drift of 2.5 N. S62 compares this value with a preset aging threshold of 2.0 N. The aging confirmation cycle in S63 is set to 10,000 cycles. When S64 monitors the 10,000th cycle, it finds that the long-term drift of 2.5 N is consistently greater than the aging threshold of 2.0 N during this cycle, thus confirming that the aging judgment condition has been met. The system then uses this 2.5 N as a model correction value to update the force value data of the reference force-displacement model in S3 at the corresponding location point, for example, updating the 55 N reference at that point to 57.5 N.

[0096] S7. The first force estimate after dynamic compensation is used as the final clamping force control command output.

[0097] Specifically, in one embodiment, the sub-steps of S7 include S71-S75.

[0098] S71. Monitor the current operating stage of the servo pressure component in real time to determine whether the driver of the servo pressure component should be in position control mode or force control mode.

[0099] S72. When the servo pressing component is in the rapid approach operation phase, the driver of the servo pressing component is kept in the position control mode.

[0100] S73. When the motor position data of the servo pressing component reaches a preset force / position switching coordinate, the driver of the servo pressing component is switched to the force control mode.

[0101] S74. In the force control mode, the first force estimate after dynamic compensation is sent in real time as the target set value to the internal torque control loop of the driver of the servo pressing component.

[0102] S75. The internal torque control loop of the driver of the servo pressing component automatically adjusts the output current according to the deviation between the target setting value and the actual motor current, so that the actual output pressing force of the servo pressing component tracks the first force estimation value after dynamic compensation.

[0103] Position control mode is a working state of the servo system. Its control objective is to ensure that the actual position of the servo pressing component accurately tracks a set position command. The S72 uses this mode during the rapid approach phase, which allows the pressing component to move at maximum speed to the position where it is about to contact the conductive sheet. Force control mode is another working state of the servo system. Its control objective is to ensure that the force or torque output by the servo motor accurately tracks a set force command, and its final stopping position is determined by the reaction force of the object being subjected to the force.

[0104] The preset force / position switching coordinates are typically set to a point very close to the surface of the conductive sheet before the pressure assembly contacts it, for example, 0.1 mm from the surface of the conductive sheet. When the motor position data of S1 reaches this coordinate, the system determines that physical contact is about to occur and must switch from high-speed position control to precise force control.

[0105] The internal torque control loop of the servo driver is the lowest-level and fastest-responding control loop in the servo driver hardware. It monitors the actual motor current at high frequency and compares it with the target setpoint, that is, with the current command converted from the force command. This torque control loop can be controlled by the target setpoint because its built-in algorithm calculates the deviation between the target setpoint and the actual current in real time, and changes the motor voltage by adjusting the PWM output at high speed, thereby enabling the actual current to quickly track the target setpoint.

[0106] S71-S75 translate the calculated, real-time calibrated force estimate into a precise physical clamping action. This process is achieved through a hybrid control mode. Taking conductive sheet clamping as an example, S71 and S72 first cause the clamping assembly to descend rapidly in position control mode. S73 monitors that its motor position data has reached, for example, a force / position switching coordinate of 20.4 mm. The system immediately switches to force control mode and executes S74. S74 sends the real-time calibrated force estimate output from S55, for example, 108.7 N, as the target setpoint to the internal torque control loop. The torque control loop in S75 then adjusts the motor current to precisely apply and maintain the actual output clamping force of the clamping assembly at 108.7 N, completing the precise clamping of the conductive sheet.

[0107] 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 the present invention.

[0108] In one embodiment, a computer device is provided, which may be a server. The computer device includes a processor, memory, a network interface, and a database connected via a system bus. The processor provides computing and control capabilities. The memory includes a non-volatile storage medium and internal memory. The non-volatile storage medium stores an operating system, computer programs, and a database. The internal memory provides an environment for the operation of the operating system and computer programs in the non-volatile storage medium. The database contains data related to a conductive sheet clamping force control method applicable to automotive connectors. The network interface is used for communication with external terminals via a network connection. When the computer program is executed by the processor, it implements a conductive sheet clamping force control method applicable to automotive connectors.

[0109] In one embodiment, a computer device is provided, including 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 conductive sheet clamping force control method applicable to automotive connectors described in the above embodiment.

[0110] In one embodiment, a computer-readable storage medium is provided having a computer program stored thereon, which, when executed by a processor, implements the conductive sheet clamping force control method applicable to automotive connectors described in the above embodiments.

[0111] Those skilled in the art will understand that all or part of the processes in the methods of the above embodiments can be implemented by a computer program instructing related hardware. This computer program can be stored in a non-volatile computer-readable storage medium. When executed, the computer program can include the processes of the embodiments of the above methods. Any references to memory, storage, databases, or other media used in the embodiments of this application can include non-volatile and / or volatile memory. Non-volatile memory can include read-only memory (ROM), programmable ROM (PROM), electrically programmable ROM (EPROM), electrically erasable programmable ROM (EEPROM), or flash memory. Volatile memory can include random access memory (RAM) or external cache memory. By way of illustration and not limitation, RAM is available in various forms, such as static RAM (SRAM), dynamic RAM (DRAM), synchronous DRAM (SDRAM), dual data rate SDRAM (DDRSDRAM), enhanced SDRAM (ESDRAM), synchronous link DRAM (SLDRAM), Rambus direct RAM (RDRAM), direct memory bus dynamic RAM (DRDRAM), and memory bus dynamic RAM (RDRAM), etc.

[0112] Those skilled in the art will clearly understand that, for the sake of convenience and brevity, the above-described division of functional units and modules is used as an example. In practical applications, the above functions can be assigned to different functional units and modules as needed, that is, the internal structure of the device can be divided into different functional units or modules to complete all or part of the functions described above.

[0113] The above embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit it. Although the present invention 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 the present invention, and should all be included within the protection scope of the present invention.

Claims

1. A method for controlling the clamping force of conductive sheets in automotive connectors, characterized in that, Includes the following steps: S1. Real-time acquisition of motor current and motor position data of the servo pressing component; S2. Based on the motor current data, generate a first force estimate through a first calculation path; S3. Based on a preset reference force-displacement model and the motor position data, generate a second force estimate through a second calculation path; S4. Calculate the instantaneous deviation between the first force estimate and the second force estimate in real time; S5. The instantaneous deviation is fed into at least one fast feedback loop, which generates a short-term correction and uses the short-term correction to dynamically compensate the first force estimate; S6. The instantaneous deviation is fed into at least one slow feedback loop, which accumulates the instantaneous deviation to generate a long-term drift, and when the long-term drift meets a preset aging judgment condition, it triggers an adaptive update of the reference force-displacement model or the first calculation path; S7. The first force estimate after dynamic compensation is used as the final clamping force control command output.

2. The method for controlling the clamping force of conductive sheets in automotive connectors according to claim 1, characterized in that, The step S1 also includes a preprocessing step: the acquired motor current data and motor position data are filtered by a rate of change limiter before being sent to S2 and S3 to remove instantaneous spike data caused by electrical interference or encoder jumps, and a fail-safe mode is triggered when the data fails continuously.

3. The method for controlling the clamping force of conductive sheets in automotive connectors according to claim 1, characterized in that, The sub-step of S2 includes: S21. Calculating a dynamic compensation current required to overcome the inertia of the motor and mechanical load based on the second derivative of the motor position data and a preset system inertia model; S22. Subtracting the dynamic compensation current from the motor current data to obtain a quasi-static current; S23. Multiplying the quasi-static current by a preset current-force conversion coefficient to generate a preliminary force estimate; S24. Processing the preliminary force estimate through a low-pass filter to eliminate instantaneous high-frequency fluctuations caused by current sampling noise, and outputting the filtered result as the first force estimate.

4. The method for controlling the clamping force of conductive sheets in automotive connectors according to claim 1, characterized in that, The sub-step of S3 includes: S31. Obtaining real-time system operating condition parameters, wherein the real-time system operating condition parameters are used to characterize the current operating state of the mold or the properties of the processed material; S32. Using the real-time system operating condition parameters, querying a preset reference force-displacement model to retrieve one or more basic force-displacement curves associated with the real-time system operating condition; S33. When multiple basic force-displacement curves are retrieved, performing inter-model interpolation or fusion processing on the multiple basic force-displacement curves according to the closeness between the real-time system operating condition and the corresponding operating conditions of the multiple basic force-displacement curves to generate a transient force-displacement curve specifically for the current operating condition; S34. Performing model interpolation calculation on the transient force-displacement curve based on the motor position data to determine and output the second force estimation value.

5. The method for controlling the clamping force of conductive sheets in automotive connectors according to claim 1, characterized in that, The sub-step of S4 includes: S41. Subtracting the second force estimation value from the first force estimation value to calculate an initial deviation value; S42. Comparing the absolute value of the initial deviation value with a preset insensitive area threshold; when the absolute value of the initial deviation value is less than the insensitive area threshold, forcing the instantaneous deviation to be defined as zero; when the absolute value of the initial deviation value is greater than or equal to the insensitive area threshold, outputting the initial deviation value as the instantaneous deviation.

6. The method for controlling the clamping force of conductive sheets in automotive connectors according to claim 1, characterized in that, The sub-step of S5 includes: S51. Using the instantaneous deviation as a control input signal of the fast feedback loop; S52. In the fast feedback loop, applying a preset proportional algorithm to calculate a proportional correction component based on the current amplitude of the instantaneous deviation; S53. In the fast feedback loop, applying a preset integral algorithm to calculate an integral correction component based on the accumulation of the instantaneous deviation over time, to eliminate steady-state drift, wherein the steady-state drift may be caused by motor temperature rise; S54. Superimposing the proportional correction component and the integral correction component to generate a short-term correction amount; S55. Arithmetically applying the short-term correction amount to the first force estimate in real time to complete dynamic compensation, thereby obtaining a force estimate that is calibrated in real time.

7. The method for controlling the clamping force of conductive sheets in automotive connectors according to claim 1, characterized in that, The sub-step of S6 includes: S61. Feeding the instantaneous deviation into a time-weighted integrator of the slow feedback loop, wherein the time-weighted integrator is used to accumulate the instantaneous deviation for a preset period to generate the long-term drift; S62. Monitoring the long-term drift output by the time-weighted integrator and continuously comparing it with a preset aging threshold; wherein the aging threshold is used to characterize irreversible mechanical wear; S63. Setting an aging confirmation period, wherein the aging confirmation period is multiple consecutive working cycles or a preset number of operating hours; S64. When the long-term drift is continuously greater than the aging threshold within the aging confirmation period, the aging judgment condition is confirmed to be met; when the aging judgment condition is met, calculating the model correction amount based on the long-term drift amount, and using the model correction amount, performing adaptive updates on the conversion coefficients of the first calculation path or the data of the reference force-displacement model.

8. The method for controlling the clamping force of conductive sheets in automotive connectors according to claim 1, characterized in that, The sub-steps of S7 include: S71. Real-time monitoring of the current operating stage of the servo pressing component to determine whether the driver of the servo pressing component should be in position control mode or force control mode; S72. When the servo pressing component is in the rapid approach operating stage, keeping the driver of the servo pressing component in the position control mode; S73. When the motor position data of the servo pressing component reaches a preset force / position switching coordinate, switching the driver of the servo pressing component to the force control mode; S74. In the force control mode, sending the dynamically compensated first force estimate as the target set value to the internal torque control loop of the driver of the servo pressing component in real time; S75. The internal torque control loop of the driver of the servo pressing component automatically adjusts the output current according to the deviation between the target set value and the actual motor current, so that the actual output clamping force of the servo pressing component tracks the dynamically compensated first force estimate.

9. A computer device, characterized in that, It includes: One or more processors; Memory; One or more applications, wherein the one or more applications are stored in the memory and configured to be executed by the one or more processors, the one or more applications being configured to: perform the conductive sheet clamping force control method for automotive connectors according to any one of claims 1 to 8.

10. A computer-readable storage medium, characterized in that, The storage medium stores at least one instruction, at least one program, code set, or instruction set, wherein the at least one instruction, the at least one program, the code set, or the instruction set is loaded and executed by a processor to implement: the conductive sheet clamping force control method for automotive connectors as described in any one of claims 1 to 8.

Images