Automobile plate stamping parameter optimization method and system

Abstract

The invention provides an automobile plate stamping parameter optimization method and system which are applied to the technical field of industrial automation control, and the method comprises the steps: directly converting the beat deviation of a downstream station into a physical signal, feeding back the physical signal to upstream stamping equipment, driving stamping parameters to carry out proportional adjustment, and forming closed-loop feedback. Therefore, self-adaptive optimization of the stamping parameters is realized under the condition of not depending on a complex model or a rule base, and the beat deviation of the downstream station is directly and quantitatively fed back to the upstream stamping parameters under the premise of not constructing the complex model or the rule base, so that self-adaptive optimization of the stamping process is realized, and the stamping efficiency is improved. And the preset production takt of the whole production line is effectively maintained, and waste loss is reduced.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of industrial automation control, and in particular to a method and system for optimizing stamping parameters of automobile sheet metal. BACKGROUND

[0002] In an automotive body sheet metal automated stamping production line, multiple large presses are arranged in series to produce complex-shaped stamped parts, such as door inner panels or side walls. These stamped parts are then transported to downstream automated welding, riveting or assembly stations. The core goal of the production line is to strictly follow the target production cycle set by the final assembly plant to ensure efficient connection of each process. Each stamping station is pre-set with standard stamping parameters to produce parts that meet quality requirements under ideal conditions.

[0003] However, in actual production, due to factors such as sheet metal property fluctuations, die wear or press mechanical gap changes, the stamped parts may have slight geometric deviations, such as positioning hole deviation or edge springback. These deviations are difficult to be identified by the online visual detection system of the stamping station, because these systems mainly detect surface defects or macroscopic dimensions. When these stamped parts with slight deviations enter the downstream high-precision automated station, the welding robot may fail to successfully grasp or position once due to positioning hole deviation or edge springback, resulting in extended operation time and deviation of actual production cycle from the target cycle.

[0004] This partial cycle imbalance is not a device failure or a production bottleneck, but a result of subtle quality problems of the upstream stamped parts. These problems may be considered as qualified products at the stamping station, but become invisible obstacles to smooth cycle operation in downstream high-precision operations. When the central control system detects that the downstream station cycle is lagging, it traditionally compensates for the lost time by increasing the non-working stroke speed of the upstream stamping station, but this does not solve the root cause of the stamped part quality problem, and may instead cause new quality defects, such as sheet metal cracking or wrinkling, further increasing scrap rate and production cost.

[0005] Currently, the production line lacks a mechanism to directly quantify the correlation between the cycle anomaly of the downstream station and the upstream stamping parameters. Experienced process engineers can adjust the stamping parameters to improve the downstream cycle through trial and error, but this adjustment is temporary and manual, and is not recorded or learned by the system. When production switches to a new part, uses a new batch of materials or the die is maintained, these experiences are lost, causing problems to recur, increasing scrap loss and hindering continuous improvement of standard process parameters.

[0006] However, existing technologies build models, rule bases or rely on complex algorithms trained on a large amount of historical data to optimize stamping parameters. However, this approach requires high computational cost and is not conducive to popularization.

[0007] Therefore, it is currently a technical problem to directly act on the parameter adjustment mechanism of the upstream stamping station by using the beat deviation signal of the downstream station as a kind of real-time, non-intelligent physical feedback without relying on complex modeling of the stamping physical process, learning of historical data or complex logical judgment.

[0008] In view of the above problems, the prior art needs to be improved. SUMMARY

[0009] In view of the above problems, the prior art needs to be improved.

[0010] In view of the above problems, the prior art needs to be improved. S1: obtaining the deviation between the actual operation beat and the target beat of the downstream automated station in the downstream automated station of the automobile sheet stamping production line; S2: directly converting the deviation into a physical signal proportional to the deviation; S3: transmitting the physical signal to the upstream stamping equipment of the automobile sheet stamping production line; S4: controlling the upstream stamping equipment to drive the stamping parameter to be proportionally adjusted according to the intensity of the physical signal; S5: obtaining the deviation between the actual operation beat and the target beat of the downstream automated station after adjusting the stamping parameter, and forming a closed-loop feedback between the deviation and the adjustment of the stamping parameter.

[0011] The automobile sheet stamping parameter optimization method provided by the present application directly and non-computationally establishes a physical feedback mechanism, and real-time and quantitatively feeds back the beat deviation of the downstream automated station to the upstream stamping equipment, and drives the stamping parameter to be proportionally adjusted, so as to effectively absorb the downstream beat fluctuation caused by the slight quality problem of the stamping part without relying on complex models or historical data, and maintain the overall preset production beat of the production line.

[0012] Further, step S1 comprises: S11: obtaining the deviation between the actual operation beat and the target beat of each downstream automated station in a plurality of parallel downstream automated stations; S12: determining the deviation with the maximum positive value according to a plurality of deviations, and taking the deviation with the maximum positive value as the unified deviation of the downstream automated station; S13: When none of the plurality of deviations is positive, set the unified deviation of the downstream automated station to zero.

[0013] The application provides an automobile plate stamping parameter optimization method, which ensures that the most critical bottleneck problem is processed preferentially by determining the unified deviation of a plurality of parallel downstream stations.

[0014] Further, step S2 comprises: S21: inputting the deviation into a nonlinear physical conversion unit; S22: controlling the nonlinear physical conversion unit to output a physical signal having a nonlinear relationship with the deviation according to the deviation.

[0015] The application provides an automobile plate stamping parameter optimization method, which introduces nonlinear conversion, so that parameter adjustment can show different sensitivity or response intensity according to the size of the deviation.

[0016] Further, in step S22, when the deviation is in a first range, the first output gain of the nonlinear physical conversion unit is higher than the second output gain when the deviation is in a second range.

[0017] The application provides an automobile plate stamping parameter optimization method, which realizes more fine and faster control by setting different output gains in different deviation ranges.

[0018] Further, step S22 comprises: S221: configuring an analog circuit as the nonlinear physical conversion unit; S222: inputting the deviation as an input voltage or current of the analog circuit; S223: the analog circuit utilizes the non-saturation region and saturation region characteristics of a diode or an operational amplifier to output a physical signal having a nonlinear relationship with the deviation according to the deviation.

[0019] Further, step S22 further comprises: S224: configuring an operational amplifier circuit as the nonlinear physical conversion unit; S225: inputting the deviation into a comparator of the operational amplifier circuit to compare the deviation with a preset threshold to determine the range to which the deviation belongs; S226: according to the range to which the deviation belongs, controlling an analog switch of the operational amplifier circuit to switch the resistance value in the feedback network; S227: the switching of the resistance value changes the closed-loop gain of the operational amplifier circuit, so that when the deviation is in the first range, the first output gain of the nonlinear physical conversion unit is higher than the second output gain when the deviation is in the second range, and a physical signal having a nonlinear relationship with the deviation is output.

[0020] Further, step S4 comprises: S41: inputting the physical signal to an actuator associated with a specific stamping parameter adjustment mechanism; S42: controlling the actuator to output a driving amount proportional to the intensity of the physical signal according to the intensity of the physical signal; S43: adjusting the stamping parameter according to the driving amount.

[0021] Further, step S42 comprises: S421: configuring an electro-hydraulic proportional valve as the actuator; S422: inputting the physical signal as an electrical signal to the electro-hydraulic proportional valve; S423: outputting fluid pressure as the driving amount according to the intensity of the electrical signal through a relationship that the displacement of the valve core is proportional to the intensity of the electrical signal.

[0022] Further, step S5 comprises: S51: reacquiring the deviation between the actual operation tempo and the target tempo of the downstream automated station after a preset time interval or processing a preset number of stamping parts; S52: updating the physical signal transmitted upstream using the reacquired deviation to form a closed-loop feedback between the deviation and the adjustment of the stamping parameter.

[0023] In a second aspect, a system for optimizing the stamping parameters of automobile sheet metal is provided, which is used to implement any of the above methods. The system comprises: an acquisition module: acquiring the deviation between the actual operation tempo and the target tempo of the downstream automated station of an automobile sheet metal stamping production line; a conversion module: directly converting the deviation into a physical signal proportional to the deviation; a transmission module: transmitting the physical signal to the upstream stamping equipment of the automobile sheet metal stamping production line; a control module: controlling the upstream stamping equipment to drive proportional adjustment of the stamping parameter according to the intensity of the physical signal; a feedback adjustment module: acquiring the deviation between the actual operation tempo and the target tempo of the downstream automated station after adjusting the stamping parameter to form a closed-loop feedback between the deviation and the adjustment of the stamping parameter.

[0024] Beneficial effects: the automobile plate stamping parameter optimization method and system provided by the application directly converts the beat deviation of the downstream station into a physical signal and feeds it back to the upstream stamping equipment, drives the stamping parameter to make proportional adjustment, forms a closed loop feedback, so as to realize adaptive optimization of the stamping parameter without relying on a complex model or rule base, has the advantages of directly and quantitatively feeding the beat deviation of the downstream station back to the upstream stamping parameter without constructing a complex model or rule base, so as to realize adaptive optimization of the stamping process, effectively maintain the preset production beat of the entire production line, and reduce waste loss. BRIEF DESCRIPTION OF DRAWINGS

[0025] Figure 1 A flowchart of the automobile plate stamping parameter optimization method provided by the application.

[0026] Figure 2 A structure diagram of the automobile plate stamping parameter optimization system provided by the application.

[0027] Figure 3 An architecture diagram of the automobile plate stamping parameter optimization system provided by the application.

[0028] Figure 4 A circuit diagram of an operational amplifier provided by the application.

[0029] Label explanation: 201, acquisition module; 202, conversion module; 203, transmission module; 204, control module; 205, feedback adjustment module. DETAILED DESCRIPTION

[0030] The technical solutions in the embodiments of the application will be described clearly and completely below with reference to the drawings in the embodiments of the application. Obviously, the described embodiments are only part of the embodiments of the application, rather than all the embodiments. The components of the embodiments of the application described and indicated in the drawings can be arranged and designed in various different configurations. Therefore, the following detailed description of the embodiments of the application provided in the drawings is not intended to limit the scope of the claimed application, but only represents selected embodiments of the application. Based on the embodiments of the application, all other embodiments obtained by those skilled in the art without creative work are within the scope of protection of the application.

[0031] It should be noted that: similar reference numbers and letters represent similar items in the following drawings, so once an item is defined in one drawing, it does not need to be further defined and explained in subsequent drawings. Meanwhile, in the description of the application, the terms "first, second" and the like are only used to distinguish the description, and cannot be understood as indicating or implying relative importance.

[0032] In a first aspect, a method for optimizing stamping parameters of an automobile sheet is provided, the method comprising the steps of: S1: obtaining a deviation between an actual cycle time and a target cycle time of a downstream automated station of an automobile sheet stamping line; S2: directly converting the deviation into a physical signal proportional to the deviation; S3: transmitting the physical signal to an upstream stamping device of the automobile sheet stamping line; S4: controlling the upstream stamping device to drive proportional adjustment of stamping parameters according to the intensity of the physical signal; S5: obtaining the deviation between the actual cycle time and the target cycle time of the downstream automated station after adjusting the stamping parameters, forming a closed-loop feedback between the deviation and the adjustment of the stamping parameters.

[0033] The downstream automated station refers to an automated workstation for subsequent processing of stamped parts after the stamping device in the automobile sheet stamping line, such as an automated welding station, a riveting station, or an assembly station, which is introduced to capture production cycle abnormalities caused by quality problems of upstream stamped parts.

[0034] The deviation between the actual cycle time and the target cycle time refers to the difference between the time required for the downstream automated station to complete a single or a batch of stamped part operations and the preset standard time, which quantifies the imbalance of local efficiency of the production line and indicates the impact of quality problems of upstream stamped parts on downstream processes.

[0035] Directly converting the deviation into a physical signal proportional to the deviation refers to directly mapping the numerical value of the cycle deviation into the intensity of a physical quantity without calculation, model reasoning, or data lookup, and the conversion is nonlinear, which aims to convert abstract cycle deviation information into a physical quantity that can be directly perceived by the upstream device and has driving capability.

[0036] The physical signal refers to a physical quantity that can carry information and transmit it, such as an electrical signal, a hydraulic signal, or a pneumatic signal, which serves as a carrier of downstream cycle deviation information to transmit adjustment instructions to the upstream stamping device.

[0037] Proportional adjustment refers to a direct and quantifiable correspondence between the adjustment amount of the stamping parameters (such as slider speed, bottom dead center position, and blank holder force) of the upstream stamping device and the intensity of the received physical signal, which ensures the responsiveness of parameter adjustment, so that the change of parameters can directly reflect the size of the downstream cycle deviation.

[0038] The closed-loop feedback refers to that after the adjustment of the stamping parameters, the system again acquires the beat deviation of the downstream automated station, and inputs the new deviation information into the adjustment process again, forming a continuous and self-correcting cycle, the purpose of which is to ensure that the system can continuously optimize according to the real-time state of the production line, maintain the stability of the production beat, and adapt to the changes in the production process.

[0039] Specifically, the method realizes the adaptive optimization of the automobile panel stamping parameters by establishing a direct physical feedback loop. First, at the downstream automated station of the automobile panel stamping production line, the system acquires the deviation between the actual operation beat and the preset target beat of the station. This deviation quantifies the efficiency loss of the downstream process due to the quality problems of the upstream stamping parts.

[0040] Subsequently, the deviation is directly converted into a physical signal proportional to the deviation intensity, and the conversion process avoids calculation or model dependence, ensuring the immediacy of the feedback. The converted physical signal is transmitted to the upstream stamping equipment of the production line.

[0041] After receiving the physical signal, the upstream stamping equipment drives the internal stamping parameters to make proportional adjustments according to the intensity of the signal. This adjustment is direct and quantitative, ensuring that the adjustment of the stamping parameters can accurately respond to the beat deviation of the downstream.

[0042] After the adjustment of the stamping parameters is completed, the system again acquires the deviation between the actual operation beat and the target beat of the downstream automated station. The new deviation information is used to update the physical signal transmitted to the upstream, thereby forming a continuous and self-correcting closed-loop feedback mechanism. The closed loop ensures that the system can evaluate the effect of parameter adjustment in real time, and continuously optimize the stamping parameters according to the dynamic changes of the production line, thereby effectively absorbing the beat fluctuations of the downstream process caused by the slight quality problems of the stamping parts without affecting the product quality, and ultimately maintaining the overall preset production beat of the production line.

[0043] As a preferred embodiment, the scheme of the present application is implemented as follows: At the downstream automated welding station of the automobile panel stamping production line, the operation time of the welding robot is monitored in real time by a sensor, and compared with the preset welding beat, thereby acquiring the deviation between the actual operation beat and the target beat. For example, when the welding robot tries to grab or adjust the posture multiple times due to inaccurate part positioning, the operation time will be prolonged, resulting in a positive deviation.

[0044] The deviation is then input to an analog conversion circuit, which uses the non-linear characteristics of operational amplifiers or diodes to directly convert the deviation into an analog voltage signal whose strength is proportional to the deviation. For example, the greater the deviation, the higher the output voltage. The analog voltage signal is transmitted to the upstream press equipment controller via industrial Ethernet or dedicated analog signal cables.

[0045] After receiving the analog voltage signal, the press equipment controller inputs it to the drive circuit of an electro-hydraulic proportional valve. The electro-hydraulic proportional valve controls the flow and pressure of hydraulic oil according to the strength of the received voltage signal, thereby driving the slider bottom dead center position or the blank holder force of the press to fine-tune. For example, the higher the voltage signal, the greater the hydraulic pressure output by the electro-hydraulic proportional valve, thereby increasing the blank holder force or adjusting the bottom dead center position.

[0046] After the adjustment of the stamping parameters, for example, after producing a preset number of stamped parts or after a preset time interval, the operating tempo of the downstream welding station is monitored again to obtain a new deviation. The new deviation is again input to the analog conversion circuit, forming a continuous feedback loop, so that the stamping parameters can be dynamically adjusted according to the real-time conditions of the production line, ensuring the quality of the stamped parts and maintaining the stable operation of the production line.

[0047] Further, step S1 includes: S11: respectively obtaining the deviation of the actual operating tempo from the target tempo of each downstream automated station in a plurality of parallel downstream automated stations; S12: determining the deviation with the largest positive value among the plurality of deviations, and taking the deviation with the largest positive value as the unified deviation of the downstream automated stations; S13: when none of the plurality of deviations is positive, setting the unified deviation of the downstream automated stations to zero.

[0048] Among them, the unified deviation refers to a single value that can represent the most prominent or most attention- demanding tempo problem of the entire downstream production line after specific logical processing when there are tempo differences among multiple parallel stations. It can be determined by selecting the maximum positive deviation, or it can be obtained by weighted average or priority sorting.

[0049] The present scheme refines the steps of obtaining the tempo deviation of the downstream automated stations, aiming to solve the problem of how to accurately and representatively obtain the tempo deviation when there are multiple downstream automated stations, so as to ensure that the adjustment of the upstream stamping parameters can effectively target the actual bottleneck of the production line.

[0050] During the production line operation, firstly, the deviation of the actual operation cycle from the target cycle of each downstream automated station is obtained in multiple parallel downstream automated stations. This process comprehensively monitors the running state of each station, providing necessary data basis for subsequent unified deviation determination, avoiding missing other potential bottlenecks due to only focusing on a single station.

[0051] Subsequently, according to the obtained multiple deviations, the system strategically determines the deviation with the largest positive value among them and takes this largest positive value deviation as the unified deviation of the downstream automated station. The positive value deviation indicates that the actual operation cycle exceeds the target cycle, i.e., the station has a lag, becoming the current bottleneck of the production line. Selecting the largest positive value deviation as the unified deviation ensures that the system can focus on the most serious bottleneck station, thus feeding back the signal most representative of the current production line efficiency problem to the upstream stamping equipment.

[0052] This mechanism ensures that the adjustment of stamping parameters is made for the most urgent problem, effectively alleviating the cycle pressure downstream, avoiding unnecessary or ineffective adjustment of non-bottleneck stations.

[0053] In addition, the present scheme also considers the normal running state where all downstream stations do not have cycle lag (i.e., all deviations are negative or zero). In this case, when multiple deviations are not positive, the unified deviation of the downstream automated station will be set to zero. This means that there is no urgent cycle problem to be solved at present, so there is no need to send an adjustment signal to the upstream stamping equipment.

[0054] This avoids unnecessary adjustments of upstream stamping parameters when the production line is running normally or even ahead, thus maintaining the stability of the production line and the quality of the stamped parts, preventing over-adjustment or misadjustment.

[0055] Further, step S2 comprises: S21: inputting the deviation into a nonlinear physical conversion unit; S22: controlling the nonlinear physical conversion unit to output a physical signal having a nonlinear relationship with the deviation according to the deviation.

[0056] The nonlinear physical conversion unit is a device for converting the input signal (i.e., the deviation) into an output physical signal, and the conversion relationship is nonlinear. This means that the strength or rate of change of the output signal does not have a fixed proportional relationship with the strength or rate of change of the input signal. For example, when the input deviation is small, the change of the output signal can be relatively gentle; when the input deviation is large, the change of the output signal can be more obvious.

[0057] The unit can be composed of various physical or electronic components, which are introduced to enable the system to provide more flexible and adaptive responses according to the different sizes of the deviation, thereby improving the control effect. The physical signal with a nonlinear relationship with the deviation is the output of the nonlinear physical conversion unit, which is a physical quantity such as voltage, current, pressure or flow, and the value or intensity of which has a nonlinear relationship with the input deviation value.

[0058] This nonlinear relationship means that for the same increment of input deviation, the increment of output physical signal can be different, or the gain of output signal (the ratio of output change to input change) will change with the size of input deviation. The characteristics of such signals enable subsequent punch parameter adjustment to respond more subtly or more forcefully according to the actual situation of the deviation, thereby avoiding the problems of insufficient or excessive adjustment that may be caused by linear relationship.

[0059] Further, in step S22, when the deviation is in the first range, the first output gain of the nonlinear physical conversion unit is higher than the second output gain when the deviation is in the second range.

[0060] Wherein, the first range refers to a specific interval of the value of the deviation signal, for example, it can be set as an interval where the deviation value is greater than a certain preset threshold, or an interval of a larger deviation. The second range refers to another specific interval of the value of the deviation signal, for example, it can be set as an interval where the deviation value is less than or equal to the preset threshold, or an interval of a smaller deviation. The division of these ranges can be adjusted and set according to the beat fluctuation characteristics and adjustment requirements of the actual production line.

[0061] The first output gain refers to the amplification coefficient or conversion sensitivity of the nonlinear physical conversion unit when the deviation is in the first range. The second output gain refers to the amplification coefficient or conversion sensitivity of the nonlinear physical conversion unit when the deviation is in the second range.

[0062] The nonlinear physical conversion unit can be a circuit or module that can dynamically adjust the conversion ratio between its output and input according to the amplitude or range of the input signal, for example, it can be an analog circuit with piecewise linear or piecewise nonlinear characteristics, or a hybrid circuit that controls analog gain through digital logic.

[0063] Further, step S22 includes: S221: configuring an analog circuit as the nonlinear physical conversion unit; S222: taking the deviation as the input voltage or current of the analog circuit; S223: The analog circuit utilizes the non-saturation region and saturation region characteristics of diodes or operational amplifiers to output a physical signal having a non-linear relationship with the deviation according to the deviation.

[0064] Based on the understanding of the technical features described above, the present scheme optimizes the step of converting the beat deviation into a physical signal, realizes the non-linear conversion between the deviation and the physical signal in a direct and physical level, and presents different output gains according to the deviation size. Specifically, first, the analog circuit is configured as a non-linear physical conversion unit, which provides a basis for subsequent non-linear processing, because the analog circuit can directly process continuous physical quantities, avoiding digital conversion and complex digital logic processing, thereby meeting the requirement of the present application for a direct, non-computational physical feedback mechanism. Then, the obtained beat deviation is directly converted into an electrical signal form, such as voltage or current, which can be recognized and processed by the analog circuit, as the input of the analog circuit.

[0065] This direct conversion establishes a physical link between the deviation information and the circuit input, so that the deviation can directly drive the analog circuit for processing. Subsequently, the analog circuit utilizes the inherent non-linear characteristics of its internal electronic components, such as the current-voltage relationship of diodes at different forward voltages, or the response difference between the non-saturation region and the saturation region of operational amplifiers, to automatically adjust its output gain according to the size of the input deviation, and output a physical signal having a non-linear relationship with the deviation. For example, when the deviation is small, the circuit may work in a low-gain region, so that the output signal changes relatively gently; when the deviation is large, the circuit may enter a high-gain region, so that the output signal changes more dramatically. This implementation based on the physical characteristics of components avoids complex software programming, lookup tables or model construction, thereby effectively solving the technical problem of realizing non-linear feedback regulation without relying on complex calculations or preset models.

[0066] The nonlinear physical conversion mechanism based on analog circuit is applied to the entire stamping parameter optimization method, so that the system can convert the beat deviation of the downstream automated station into a physical signal with a nonlinear relationship through a direct and physical conversion method. This physical signal is then transmitted to the upstream stamping equipment and drives the adjustment of the stamping parameters. When the deviation is small, the change in the physical signal is relatively mild, and the adjustment of the stamping parameters is also relatively fine; when the deviation is large, the change in the physical signal is more significant, which can prompt the stamping parameters to adjust more quickly and more substantially. This response mechanism enables the entire closed-loop feedback system to exhibit stronger adaptability to downstream beat fluctuations. In particular, when a small mass defect of the stamped part causes a large deviation in the beat of the downstream station, this nonlinear conversion can provide stronger feedback strength to accelerate the adjustment of the stamping parameters, thereby more quickly absorbing the beat fluctuations and avoiding further decline in the efficiency of the production line. This direct physical feedback method has advantages in real-time performance, response speed, and system simplicity compared to traditional schemes based on complex calculations or preset models, ensuring that the adaptive adjustment of the stamping process effectively maintains the preset production beat of the production line without sacrificing product quality.

[0067] To further illustrate the implementation details of the above scheme, in an embodiment, the nonlinear physical conversion unit can be configured as an analog circuit composed of resistors and diodes.

[0068] Specifically, the beat deviation can be converted into a continuously changing voltage signal by a sensor as the input voltage of the analog circuit. The analog circuit can include a series resistor and one or more parallel diodes, or a logarithmic amplifier or exponential amplifier composed of operational amplifiers and diodes. When the input deviation voltage is small, the diode can be in the initial region of its forward conduction, at which time its equivalent resistance is large and the output gain of the circuit is relatively low, and the output voltage changes relatively gently with the input voltage. As the input deviation voltage gradually increases and reaches a certain threshold, the diode will enter the linear region of its forward conduction, and its equivalent resistance will decrease, causing the output gain of the circuit to increase significantly and the output voltage to change more dramatically with the input voltage. In this way, the analog circuit uses the inherent nonlinear voltage-current characteristics of the diode to automatically output a physical signal with a nonlinear relationship with the deviation without any digital processing or lookup table, and exhibits different output gains when the deviation is in different ranges. For example, when the deviation is small, the output signal changes less, corresponding to a lower gain; when the deviation is large, the output signal changes more, corresponding to a higher gain.

[0069] Further, step S22 further includes: S224: configuring an operational amplifier circuit as a nonlinear physical conversion unit; S225: input the deviation to a comparator of an operational amplifier circuit, compare the deviation with a preset threshold value to determine the range to which the deviation belongs; S226: according to the range to which the deviation belongs, control an analog switch of the operational amplifier circuit to switch the resistance value in the feedback network; S227: the switching of the resistance value changes the closed-loop gain of the operational amplifier circuit, so that when the deviation is in the first range, the first output gain of the nonlinear physical conversion unit is higher than the second output gain when the deviation is in the second range, and a physical signal having a nonlinear relationship with the deviation is output.

[0070] Please refer to Figure 4 , wherein the operational amplifier circuit refers to a high-gain, differential-input, DC-coupled voltage amplifier, which can be realized by an integrated circuit chip or a circuit built by discrete components, as the core analog processing unit for realizing nonlinear physical conversion in the present scheme.

[0071] The comparator refers to an electronic circuit for comparing the sizes of two input signals, and when one input signal exceeds another preset reference signal, the output state will jump, which can be realized by a dedicated comparator integrated circuit or by configuring the operational amplifier in open-loop mode.

[0072] The preset threshold value refers to the reference level used to judge the size limit of the deviation in the comparator, which can be realized by a voltage reference source, an adjustable resistance voltage divider, or a voltage output by a digital-to-analog converter. The range to which the deviation belongs refers to dividing the deviation into different numerical intervals according to the comparison result of the deviation and the preset threshold value, such as the range greater than the threshold value or the range less than the threshold value.

[0073] The analog switch refers to an electronic component that can switch the analog signal path according to the on-off of the control signal, which can be realized by a field effect transistor switch, a bipolar transistor switch, or a dedicated analog switch integrated circuit.

[0074] The resistance value in the feedback network refers to the numerical value of the resistance element connected between the output and input terminals of the operational amplifier, which is used to determine the closed-loop gain of the operational amplifier, which can be realized by a fixed resistance, an adjustable resistance, or a resistance network composed of multiple resistances through switching. The closed-loop gain refers to the ratio between the output signal and the input signal of the operational amplifier circuit under negative feedback configuration, which is determined by the parameters of the feedback network.

[0075] In one embodiment, the non-linear physical conversion unit can be configured as a piecewise gain amplifier circuit based on an operational amplifier. The circuit can employ a general purpose operational amplifier such as LM358 or OP07. A bias, such as a voltage signal representing the tempo delay, is input to the input of the operational amplifier circuit. Meanwhile, a comparator circuit, which can be configured as a voltage comparator mode by another operational amplifier or using a dedicated comparator chip such as LM339, is used to compare the bias with a preset threshold. The preset threshold can be provided by a voltage reference source through a resistor divider, for example, set to 0.5 volts. When the voltage value of the bias is higher than 0.5 volts, the comparator outputs a high level, indicating that the bias is in the first range.

[0076] When the voltage value of the bias is lower than or equal to 0.5 volts, the comparator outputs a low level, indicating that the bias is in the second range. The output signal of the comparator is sent to the control end of one or more analog switches, which can employ a CMOS analog switch integrated circuit such as CD4066. The analog switches are connected in the feedback network of the operational amplifier and are used to switch the combination of feedback resistors. For example, in the non-inverting amplification configuration of the operational amplifier, its closed-loop gain is determined by the feedback resistor R_f and the input resistor R_in. When the bias is in the first range, the analog switches can be switched so that a larger feedback resistor R_f1 is connected to the circuit, so that the closed-loop gain of the operational amplifier circuit is higher, for example, set to 5. At this time, the first output gain of the non-linear physical conversion unit is 5.

[0077] When the bias is in the second range, the analog switches are switched so that a smaller feedback resistor R_f2 is connected to the circuit, so that the closed-loop gain of the operational amplifier circuit is lower, for example, set to 2. At this time, the second output gain of the non-linear physical conversion unit is 2.

[0078] In this way, when the bias is large, the output physical signal responds more strongly to the bias; when the bias is small, the output physical signal responds more gently to the bias. Finally, the voltage signal output by the operational amplifier circuit is a physical signal having a non-linear relationship with the bias, and the strength of the signal will be used to drive the adjustment of the upstream stamping parameter.

[0079] Further, step S4 comprises: S41: inputting the physical signal to an actuator associated with the specific stamping parameter adjustment mechanism; S42: controlling the actuator to output a driving amount proportional to the strength of the physical signal according to the strength of the physical signal; S43: adjusting the stamping parameter according to the driving amount.

[0080] Specific press parameter adjustment mechanism refers to a mechanical or hydraulic component used to change the working parameters of the press equipment, such as a lead screw mechanism for adjusting the lower dead point position of the slide, a hydraulic cylinder for changing the blank holder force, or a servo motor for controlling the press speed.

[0081] Actuator refers to a device that can convert an input physical signal into mechanical movement or physical output, which can be implemented by an electric actuator, a hydraulic actuator, a pneumatic actuator, or a piezoelectric actuator. Driving quantity refers to the physical output of the actuator generated according to the strength of the physical signal, which directly acts on the adjustment mechanism, and can be expressed as displacement, force, torque, fluid pressure, or flow.

[0082] The present scheme specifically converts the abstract press parameter proportional adjustment process into a series of physical level direct operations, thereby solving the problem of converting downstream cycle deviation into a physical signal to directly and non-computational affect the upstream press parameter adjustment.

[0083] In one embodiment, when the downstream automated station detects the cycle deviation and converts it into a voltage signal as a physical signal, the voltage signal can be directly input to a servo motor driver associated with the lower dead point adjustment mechanism of the press equipment slide. The servo motor driver acts as an actuator, and its circuit is configured to output an electric current proportional to the voltage intensity according to the input voltage signal intensity.

[0084] This current directly drives the servo motor to rotate as a driving quantity. The servo motor is connected to the lower dead point adjustment mechanism of the press equipment slide through a lead screw mechanism. When the servo motor rotates, it drives the lead screw mechanism to move, thereby adjusting the lower dead point position of the press equipment slide. For example, if the downstream cycle deviation increases, the voltage signal intensity increases accordingly, and the electric current output by the servo motor driver also increases, causing the servo motor to rotate at an angle, thereby further adjusting the lower dead point position of the slide. In this way, the downstream cycle deviation can directly and proportionally affect the lower dead point parameter of the upstream press equipment through the physical linkage of the voltage signal, servo motor driving current, and lead screw mechanism, achieving adjustment of the press part quality and further stabilizing the production cycle.

[0085] This implementation avoids digital signal conversion and software processing, ensuring the response of the adjustment process and the direct implementation of the physical level.

[0086] Further, step S42 includes: S421: configuring an electro-hydraulic proportional valve as an actuator; S422: inputting the physical signal as an electric signal to the electro-hydraulic proportional valve; S423: according to the electric signal intensity, outputting the fluid pressure as a driving quantity through the proportional relationship between the valve core displacement and the electric signal intensity.

[0087] Wherein, electro-hydraulic proportional valve refers to a kind of control valve which can convert input electrical signal into proportional hydraulic output (such as flow or pressure).

[0088] Taking physical signal as electrical signal refers to taking physical quantity representing downstream beat deviation, such as voltage or current, as control input signal of electro-hydraulic proportional valve. The proportional relationship between spool displacement and electrical signal intensity refers to the linear or approximately linear corresponding relationship between the displacement of the spool inside the electro-hydraulic proportional valve under the action of electrical signal and the intensity of input electrical signal, which can be realized by directly moving the spool driven by electromagnetic force or moving the main spool through the pilot stage control.

[0089] Taking fluid pressure as driving quantity refers to the hydraulic or pneumatic pressure output by the electro-hydraulic proportional valve according to the intensity of electrical signal, which can directly act on the adjusting mechanism of the stamping equipment, and it can use hydraulic oil or compressed air as working medium.

[0090] In a specific embodiment, in order to realize accurate adjustment of stamping parameters, a direct-acting electro-hydraulic proportional directional valve can be configured as an actuator. The input end of the electro-hydraulic proportional directional valve can receive electrical signal from the upstream transmission module, such as a standard 4-20mA current signal. When the beat of the downstream automated station deviates, the deviation is converted into corresponding current signal and input to the electro-hydraulic proportional directional valve. The electromagnetic coil inside the electro-hydraulic proportional directional valve will generate a magnetic force according to the input current, which directly drives the spool to produce displacement. For example, when the current increases from 4mA to 20mA, the displacement of the spool will gradually increase from minimum to maximum, so as to accurately control the flow or pressure output of hydraulic oil. This output hydraulic pressure as driving quantity can directly act on the hydraulic cylinder of the stamping equipment, such as the hydraulic cylinder for adjusting the blank holder force or the bottom dead center position. In this way, the piston displacement or output force of the hydraulic cylinder is proportional to the intensity of the input electrical signal, so as to realize fine and continuous adjustment of stamping parameters. For example, when the downstream beat lags, the current signal increases, and the hydraulic pressure output by the electro-hydraulic proportional valve increases accordingly, driving the hydraulic cylinder to increase the pressure, so as to improve the quality of the stamped part, and then make the downstream beat return to normal.

[0091] Further, step S5 comprises: S51: Re-acquire the deviation between the actual working beat of the downstream automated station and the target beat after a preset time interval or processing a preset number of stamped parts; S52: Update the physical signal transmitted to the upstream using the re-acquired deviation, forming a closed-loop feedback between the deviation and the adjustment of stamping parameters.

[0092] The method not only obtains and feeds back the deviation once after the adjustment of the stamping parameters, but also ensures the dynamic and adaptive of the feedback loop by introducing a periodic or yield-based reacquisition mechanism.

[0093] Specifically, after the preliminary adjustment of the stamping parameters, the system will actively acquire the deviation between the actual operating tempo and the target tempo of the downstream automated station again according to a preset time interval, such as every fixed time interval, or after processing a preset number of stamping parts. This periodic or yield-based reacquisition enables the system to continuously monitor the running state of the production line, even when there is no obvious abnormality, so as to discover potential tempo fluctuations in time and avoid the failure of adjustment due to information lag.

[0094] Once the latest tempo deviation is reacquired, the system will immediately update the physical signal transmitted to the upstream stamping equipment using this latest data. This means that if the previous parameter adjustment has restored the downstream tempo to normal, the updated physical signal strength will be weakened or zeroed; otherwise, if the tempo deviation still exists or a new deviation occurs, the physical signal will be adjusted in strength accordingly to drive the upstream stamping equipment to make further parameter fine-tuning.

[0095] It is this continuous deviation acquisition and physical signal update mechanism that enables the adjustment of the upstream stamping parameters to continuously and adaptively respond to the real-time needs of the downstream station. This dynamic closed-loop feedback mechanism enables the entire stamping parameter optimization method to effectively cope with dynamic changes caused by factors such as sheet properties, die wear, or equipment status during production, thereby ensuring that the production line can maintain the preset production tempo during continuous operation, effectively absorbing tempo fluctuations caused by stamping part quality problems, and continuously optimizing the stamping process to improve the overall stability of the production line.

[0096] Please refer to Figure 2 、 Figure 3 , a system for optimizing the stamping parameters of automobile sheet, for implementing any of the above methods, the system comprising: an acquisition module 201: at the downstream automated station of the automobile sheet stamping production line, acquiring the deviation between the actual operating tempo and the target tempo of the downstream automated station; a conversion module 202: directly converting the deviation into a physical signal proportional to the deviation; a transmission module 203: transmitting the physical signal to the upstream stamping equipment of the automobile sheet stamping production line; a control module 204: controlling the upstream stamping equipment to drive the stamping parameters to make proportional adjustment according to the strength of the physical signal; The feedback adjustment module 205 obtains the deviation between the actual operation cycle of the downstream automated station and the target cycle after adjusting the stamping parameters, and forms a closed-loop feedback between the deviation and the adjustment of the stamping parameters.

[0097] The acquisition module 201 is a unit responsible for real-time monitoring and capturing the running state of the downstream automated station of the production line. It can use hardware devices such as sensors, data acquisition cards, industrial PCs, or programmable logic controllers (PLCs) in combination with corresponding software programs to achieve the collection and calculation of operation cycle data.

[0098] The conversion module 202 is a unit that converts abstract cycle deviation into a physical signal that can be transmitted and perceived. It can use analog circuits to achieve the conversion, such as converting the deviation into a voltage, current, or air pressure signal.

[0099] The transmission module 203 is a unit responsible for reliably transmitting the converted physical signal from the downstream station to the upstream stamping equipment. It can use industrial buses, wireless communication modules, optical fiber links, or dedicated analog signal cables to achieve this.

[0100] The control module 204 is a unit that accurately adjusts the stamping parameters of the upstream stamping equipment according to the received physical signal strength. It can use servo controllers, proportional valve controllers, frequency converters, or dedicated regulators integrated into the stamping equipment control system to achieve this.

[0101] The feedback adjustment module 205 is a unit that obtains the cycle deviation of the downstream station after adjusting the stamping parameters and uses it to update the upstream adjustment signal. It can use data processing units, logic judgment units, or closed-loop control algorithm modules to achieve this, ensuring that the system can continuously optimize and self-correct.

[0102] The reason why the present application can effectively solve the problem of relying on manual experience and lacking real-time adaptive ability in the prior art is that it has constructed an automated and closed-loop stamping parameter optimization system.

[0103] The system acquires the deviation between actual and target cycle times at the downstream automated stations of the automotive panel stamping line in real-time through acquisition module 201. This deviation is a direct reflection of the abnormal cycle times at the downstream stations due to minor quality defects in the upstream stamped parts, providing the raw input signal for the entire optimization process. Subsequently, conversion module 202 receives this deviation information and converts it directly into a physical signal proportional to the deviation. This direct conversion mechanism avoids complex intermediate calculations or model dependencies, allowing the abstract cycle time deviation to be transmitted in a quantifiable physical form, such as voltage or current. On this basis, transmission module 203 is responsible for timely and accurate transmission of the converted physical signal to the upstream stamping equipment of the automotive panel stamping line. Effective signal transmission is key to achieving cross-station linkage adjustment, ensuring that downstream cycle time problems can be quickly fed back to the upstream. Next, control module 204 receives the physical signal from the transmission module and adjusts the stamping parameters of the upstream stamping equipment in proportion to the strength of the signal. This means that the greater the strength of the physical signal, the greater the adjustment range of the stamping parameters, thus achieving a direct and quantitative response to the downstream cycle time deviation. For example, if the downstream cycle time is significantly delayed, the strength of the physical signal will increase accordingly, prompting a greater adjustment of the stamping parameters to correct minor defects in the upstream stamped parts.

[0104] Further, after the adjustment of the stamping parameters is completed, feedback adjustment module 205 will again acquire the deviation between the actual and target cycle times at the downstream automated stations. This new deviation value is used to update the physical signal transmitted to the upstream, forming a closed-loop feedback between the deviation and the adjustment of the stamping parameters. It is precisely due to this continuous monitoring and re-feedback mechanism that the system can continuously self-correct and optimize, ensuring that the stamping parameters are always in the best state to adapt to various minor changes that may occur during the production process.

[0105] This systematic operation mode transforms the stamping parameter adjustment process, which originally relied on manual experience and repeated trial and error, into an automated and real-time response closed-loop control process, effectively absorbing the cycle time fluctuations caused by quality problems in the stamped parts at the downstream stations without sacrificing product quality, and ultimately maintaining the preset production cycle of the entire production line, improving the overall stability and efficiency of the production line.

[0106] In this document, relational terms such as first and second and the like can be used solely to distinguish one entity or action from another entity or action without necessarily requiring or implying any actual such relationship or order between such entities or actions.

[0107] The above merely provides an example of the present application, and is not used to limit the protection scope of the present application. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application should be included in the protection scope of the present application.

Claims

1. A method for optimizing stamping parameters of an automotive sheet, characterized in that, The method comprises steps of: S1: obtaining a deviation between an actual operation tempo and a target tempo of a downstream automated station of an automobile sheet stamping production line; S2: directly converting the deviation into a physical signal proportional to the deviation; S3: transmitting the physical signal to an upstream stamping device of the automobile sheet stamping production line; S4: controlling the upstream stamping device to proportionally adjust a stamping parameter according to an intensity of the physical signal; S5: obtaining the deviation between the actual operation tempo and the target tempo of the downstream automated station after adjusting the stamping parameter, and forming a closed-loop feedback between the deviation and the adjustment of the stamping parameter.

2. The method for optimizing the stamping parameters of an automobile sheet according to claim 1, characterized in that, Step S1 comprises: S11: obtaining a deviation between an actual operation tempo and a target tempo of each of a plurality of parallel downstream automated stations; S12: determining a deviation with a maximum positive value from a plurality of deviations, and taking the deviation with the maximum positive value as a unified deviation of the downstream automated stations; S13: when none of the plurality of deviations is positive, setting the unified deviation of the downstream automated stations as zero.

3. The method for optimizing the stamping parameters of an automobile sheet metal part according to claim 1, characterized in that, Step S2 comprises: S21: inputting the deviation into a nonlinear physical conversion unit; S22: controlling the nonlinear physical conversion unit to output a physical signal having a nonlinear relationship with the deviation according to the deviation.

4. The method for optimizing the stamping parameters of an automobile sheet metal part according to claim 3, characterized in that, In step S22, a first output gain of the nonlinear physical conversion unit when the deviation is in a first range is higher than a second output gain when the deviation is in a second range.

5. The method for optimizing the stamping parameters of an automotive sheet metal part according to claim 4, characterized in that, Step S22 comprises: S221: configuring an analog circuit as the nonlinear physical conversion unit; S222: taking the deviation as an input voltage or current of the analog circuit; S223: the analog circuit uses a non-saturation region and saturation region characteristic of a diode or an operational amplifier to output a physical signal having a nonlinear relationship with the deviation according to the deviation.

6. The method for optimizing the stamping parameters of an automobile sheet metal part according to claim 5, characterized in that, Step S22 further comprises: S224: configuring an operational amplifier circuit as the nonlinear physical conversion unit; S225: inputting the deviation into a comparator of the operational amplifier circuit to determine a range to which the deviation belongs by comparing the deviation with a preset threshold value; S226: controlling an analog switch of the operational amplifier circuit to switch a resistance value in a feedback network according to the range to which the deviation belongs; S227: the switching of the resistance value changes a closed-loop gain of the operational amplifier circuit, so that a first output gain of the nonlinear physical conversion unit when the deviation is in a first range is higher than a second output gain when the deviation is in a second range, and a physical signal having a nonlinear relationship with the deviation is outputted.

7. The method for optimizing the stamping parameters of an automobile sheet metal part according to claim 1, characterized in that, Step S4 comprises: S41: inputting the physical signal into an actuator associated with a specific stamping parameter adjustment mechanism; S42: controlling the actuator to output a driving amount proportional to an intensity of the physical signal according to the intensity of the physical signal; S43: adjusting the stamping parameter according to the driving amount.

8. The method for optimizing the stamping parameters of an automotive sheet metal part according to claim 7, characterized in that, Step S42 comprises: S421: configuring an electro-hydraulic proportional valve as the actuator; S422: input the physical signal as an electrical signal to the electro-hydraulic proportional valve; S423: according to the electrical signal intensity, output fluid pressure as the driving amount through the proportional relationship between the spool displacement and the electrical signal intensity.

9. The method for optimizing the stamping parameters of an automobile sheet metal part according to claim 1, characterized in that, Step S5 includes: S51: reacquire the deviation between the actual operation tempo and the target tempo of the downstream automated station after a preset time interval or processing a preset number of stampings; S52: update the physical signal transmitted to the upstream with the reacquired deviation to form a closed-loop feedback between the deviation and the stamping parameter adjustment.

10. A system for optimizing stamping parameters of automotive sheet metal, characterized in that, The system for implementing the method of any one of claims 1-9 comprises: an acquisition module: acquiring the deviation between the actual operation tempo and the target tempo of the downstream automated station of the automobile sheet stamping production line; a conversion module: directly converting the deviation into a physical signal proportional to the deviation; a transmission module: transmitting the physical signal to the upstream stamping equipment of the automobile sheet stamping production line; a control module: controlling the upstream stamping equipment to proportionally adjust the stamping parameters according to the intensity of the physical signal; a feedback adjustment module: acquiring the deviation between the actual operation tempo and the target tempo of the downstream automated station after adjusting the stamping parameters to form a closed-loop feedback between the deviation and the stamping parameter adjustment.

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