A precision fastener industry automation production line real-time monitoring and control system

Abstract

The present application relates to the field of industrial automation monitoring control, and discloses a precision fastener industrial automation production line real-time monitoring and regulation system, comprising an energy extraction module, a state reconstruction module, a parameter feedforward module, an inverse calibration module and a control feed servo driver, wherein the energy extraction module is used to call an energy integral formula to obtain actual plastic deformation energy and convert it into a deformation energy deviation; the state reconstruction module is used to obtain a residual temperature rise deviation by using a quotient calculation algorithm, and combine the residual temperature rise deviation into a thermal-mechanical coupling state vector; the parameter feedforward module is used to process the thermal-mechanical coupling state vector based on a feedforward compensation matrix to obtain an output control vector; the inverse calibration module is used to call a power solving algorithm to extract an actual forming impedance and calculate an impedance sequence mean value, and update the feedforward compensation matrix when the absolute difference is greater than a preset threshold value. The present application breaks through the data link of the cross-process physical state to perform adaptive motion compensation, and constructs an iterative mechanism for autonomously tracking and hedging die mechanical wear, thereby improving the consistency of the large-batch fastener forming quality.

Description

Technical Field

[0001] This invention relates to the field of industrial automation monitoring and control, specifically to a real-time monitoring and control system for a precision fastener industrial automation production line. Background Technology

[0002] In the automated production of precision fasteners, existing cold heading and downstream thread rolling equipment are typically controlled independently. The work hardening state and residual heat generated by plastic deformation during the cold heading stage cannot be quantified and transferred to downstream workstations. This data isolation between processes means that the downstream thread rolling process lacks information on the physical state of the incoming material.

[0003] Due to the lack of prior state information, existing thread rolling machines generally use fixed process parameters for continuous processing. However, the hardness and thermal softening state of wires in the same batch vary physically during actual circulation, and fixed feed rates and holding times cannot adapt to changes in the forming resistance of individual fasteners. When the hardness or heat of the fastener blank deviates, fixed processing parameters can easily lead to incomplete thread profiles or out-of-tolerance dimensions, reducing the consistency of the forming quality of batch products.

[0004] Furthermore, thread rolling dies experience mechanical wear during long-term high-load operation. Existing control systems lack a closed-loop iterative mechanism for this wear, making it impossible to dynamically adjust the control model based on changes in underlying impedance. The decrease in machining accuracy caused by cumulative die wear typically requires manual downtime for spot checks and parameter recalibration, making it difficult to achieve online dynamic compensation throughout the equipment's service life. Summary of the Invention

[0005] To address the shortcomings of existing technologies, this invention provides a real-time monitoring and control system for precision fastener industrial automation production lines. This system solves the problems of existing fastener automation production lines, such as the lack of inter-process status information gaps, the inability of fixed processing parameters to adapt to individual differences in incoming materials, and the lack of a closed-loop compensation mechanism for mold wear.

[0006] To achieve the above objectives, the present invention provides the following technical solution: This invention provides a real-time monitoring and control system for an industrial automated production line of precision fasteners, including an energy extraction module, a state reconstruction module, a parameter feedforward module, and a reverse calibration module.

[0007] The energy extraction module is used to collect the spindle operating parameters, call the energy integration formula to obtain the actual plastic deformation energy and convert it into deformation energy deviation; The state reconstruction module is used to collect dual-band radiation intensity, use the quotient calculation algorithm to obtain the residual temperature rise deviation, and call the state vector construction formula to combine the residual temperature rise deviation and deformation energy deviation into a thermo-mechanical coupled state vector. The parameter feedforward module is used to call the parameter feedforward formula, process the thermo-mechanical coupling state vector based on the system's built-in feedforward compensation matrix to obtain the output control vector, and control the feed servo drive. The reverse calibration module is used to collect the transient voltage and current of the spindle drive of the wire rolling machine, call the power calculation algorithm to extract the actual forming impedance and calculate the impedance sequence mean. When the absolute difference between the impedance sequence mean and the preset theoretical impedance benchmark value is greater than the preset threshold, the matrix update formula is called to update the feedforward compensation matrix.

[0008] Furthermore, the energy extraction module includes a synchronous acquisition unit and an energy calculation unit. The synchronous acquisition unit determines the starting and ending angular displacements based on the operating status of the cold heading machine servo. During the time period corresponding to the starting and ending angular displacements, the unit synchronously acquires the spindle operating parameters through an absolute encoder and a dynamic torque sensor to generate a torque angular displacement sequence.

[0009] The energy calculation unit obtains the transient torque function based on the torque-angular displacement sequence, and calculates the actual plastic deformation energy by integrating the transient torque function using the energy integration formula. By mapping the discrete dynamic torque data to an energy characteristic scalar, the internal mechanical changes during the plastic forming stage of the fastener are quantified.

[0010] Furthermore, the energy extraction module also includes a deviation binding unit. The deviation binding unit subtracts the actual plastic deformation energy from the preset benchmark energy consumption to obtain the deformation energy deviation, allocates a unique fastener address in the main control shift register, and stores the deformation energy deviation in the unique fastener address, thereby realizing the synchronous binding of the underlying process data flow and the physical spatial position of the production line.

[0011] Furthermore, the state reconstruction module includes an environmental purification unit and an anti-interference temperature measurement unit. When the fastener is conveyed to the feed port by the stepper clamp, the environmental purification unit triggers a pneumatic purging device to physically purge the fastener surface, removing the cold heading and stretching oil from the fastener surface and resulting in a clean fastener surface.

[0012] Within the synchronization window after purging is completed, the anti-interference temperature measurement unit activates the dual-color infrared thermometer to measure the surface of the cleaned fastener and obtain the dual-band radiation intensity, eliminating the attenuation and scattering interference of the surface fluid medium on the subsequent infrared temperature measurement signal.

[0013] Furthermore, the state reconstruction module also includes a state fusion unit. The anti-disturbance temperature measurement unit uses a quotient calculation algorithm to perform a division inversion calculation on the dual-band radiation intensity to obtain the actual residual temperature, and then subtracts the actual residual temperature from the preset environmental reference temperature to obtain the residual temperature rise deviation.

[0014] The state fusion unit reads the corresponding deformation energy deviation based on the unique fastener address, calls the state vector construction formula to combine the residual temperature rise deviation and deformation energy deviation in spatial dimensions, generates a thermomechanical coupled state vector, and writes it into the system cache to form a historical state vector. The quotient calculation is used to offset the influence of absolute emissivity fluctuations, and multi-dimensional data fusion is performed between upstream cold work hardening characteristics and downstream thermal softening effects.

[0015] Furthermore, the parameter feedforward module includes a feedforward calculation unit. During the response window period before the thread rolling machine performs the rolling action, the feedforward calculation unit reads the corresponding thermomechanical coupling state vector from the system cache based on the unique fastener address, calls the parameter feedforward formula to perform a linear transformation calculation on the feedforward compensation matrix and the thermomechanical coupling state vector, and obtains the output control vector containing feed correction instructions and pressure holding correction instructions. This transforms the physical state deviation accumulated across processes into real-time motion compensation instructions at the machine tool level.

[0016] Furthermore, the parameter feedforward module also includes a dynamic execution unit. The dynamic execution unit extracts the feed correction command and the pressure holding correction command from the output control vector, and performs superposition calculations with the preset basic setting parameters to generate the final control signal. Based on the final control signal, it controls the feed servo driver, refreshes the motion planning trajectory, and drives the rolling die to complete the processing action.

[0017] Furthermore, the reverse calibration module includes an impedance extraction unit. This unit acquires the transient voltage and current of the spindle drive of the wire rolling machine in real time. It then uses a power calculation algorithm to multiply and sum the transient voltages and currents of each phase obtained from synchronous sampling, and filters the results to obtain the total transient power. The total transient power is then subtracted from the no-load operating power to obtain the forming load power. Based on a numerical mapping model, the forming load power is converted into actual metal forming mechanical resistance, and combined with the rolling line speed, the actual forming impedance is extracted. Finally, the macroscopic mechanical operating resistance of the equipment is deduced through the electrical parameters.

[0018] Furthermore, the reverse calibration module also includes a matrix adaptive unit. The matrix adaptive unit calculates the average of the actual forming impedance of multiple consecutive fasteners to obtain the impedance sequence mean. The number of consecutive fasteners is determined by the sliding window capacity. When the absolute difference between the impedance sequence mean and the theoretical impedance reference value is greater than a preset threshold, the historical state vector corresponding to each fastener is retrieved.

[0019] The sliding window sampling setting filters out random noise from a single processing cycle and extracts the macroscopic degradation trend of continuous equipment operation.

[0020] Furthermore, the matrix adaptive unit calls the matrix update formula to calculate the updated compensation matrix. The specific calculation of the matrix update formula is as follows: the difference between each actual formed impedance and the theoretical impedance reference value is multiplied by the control channel weight vector and the transpose of the historical state vector and accumulated. The correction amount is obtained by scaling the difference with the error convergence factor and the sliding window capacity. The correction amount is then subtracted from the feedforward compensation matrix to obtain the updated compensation matrix.

[0021] The matrix adaptive unit updates the compensation matrix to overwrite the feedforward compensation matrix, thus completing the real-time monitoring and control of the industrial automated production line.

[0022] This invention provides a real-time monitoring and control system for an automated production line in the precision fastener industry. It offers the following advantages: 1. This invention quantifies the work hardening characteristics of the cold heading stage through the energy integral formula, extracts the actual residual temperature that excludes oil film interference by combining physical purging and quotient calculation algorithms, and integrates multi-source physical quantities into a thermo-mechanical coupled state vector using a unique fastener address as an index, thereby opening up the data link between upstream and downstream workstations on the automated production line and providing accurate physical state basis for the thread rolling process.

[0023] 2. This invention utilizes a feedforward compensation matrix to decouple and map the thermomechanical coupling state vector, dynamically generating feed correction commands and holding pressure correction commands during the roll forming response window. The feed servo driver performs adaptive motion compensation based on the real-time physical resistance characteristics of each individual fastener, overcoming the shortcomings of traditional fixed parameters in dealing with batch differences in wire materials, and reducing the incidence of dimensional fluctuations and local forming defects.

[0024] 3. This invention utilizes a power calculation algorithm to inversely deduce the actual forming impedance from the electrical parameters of the driver. When the mean of the impedance sequence deviates from the reference threshold, the matrix update formula is triggered to iteratively correct the feedforward compensation matrix. The correction mechanism enables the system to autonomously track and compensate for the mechanical decay of the thread rolling die, maintain the precision machining quality during the die's service life, and reduce the frequency of manual downtime for parameter adjustment. Attached Figure Description

[0025] Figure 1 This is a diagram illustrating the architecture of a real-time monitoring and control system for an automated production line of precision fasteners according to the present invention. Figure 2 This is a flowchart of a real-time monitoring and control method for an industrial automated production line of precision fasteners according to the present invention. Figure 3 This is a logical architecture diagram of the energy extraction module of the present invention; Figure 4 This is a logical architecture diagram of the state reconstruction module of the present invention; Figure 5 This is a logical architecture diagram of the parameter feedforward module of the present invention; Figure 6 This is a logical architecture diagram of the reverse calibration module of the present invention; Figure 7 This is a comparison chart of thread pitch diameter fluctuation deviation in an application embodiment of the present invention. Detailed Implementation

[0026] The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0027] Please see the appendix Figure 1 This invention provides a real-time monitoring and control system for an automated precision fastener production line. The system is applied to an automated synchronous conveyor production line, specifically to the first cold heading station, the downstream thread rolling station, the cold heading machine servo spindle, the feed servo driver, the thread rolling machine spindle driver, and equipment such as stepper clamps that convey fasteners along each station and maintain the first-in-first-out spatial sequence of fastener flow. The system includes an energy extraction module, a state reconstruction module, a parameter feedforward module, and a reverse calibration module.

[0028] In this embodiment, fasteners include wire ends before entering the first cold heading station, fastener blanks after cold heading, and semi-finished fasteners entering the downstream thread rolling station; except in scenarios where process states need to be distinguished, they are all collectively referred to as fasteners.

[0029] In the first forming stage, the automated synchronous conveyor line transports the fasteners to the first cold heading station. The energy extraction module is applied to the first cold heading station of the automated synchronous conveyor line. Through the absolute encoder and dynamic torque sensor configured on the first cold heading station of the automated synchronous conveyor line, the operating parameters of the spindle of the cold heading machine are synchronously collected to quantify the mechanical change characteristics inside the fastener.

[0030] The energy extraction module generates a torque angular displacement sequence and calls the energy integration formula to calculate the actual plastic deformation energy. It then subtracts the actual plastic deformation energy from the preset benchmark energy consumption to convert it into a deformation energy deviation that can be tracked across processes. The energy extraction module completes the corresponding binding of this deformation energy deviation with the physical spatial position in the main control shift register.

[0031] As the production line advances, the stepper clamp conveys the fasteners to the feed inlet of the downstream thread rolling station. The state reconstruction module is applied at the feed inlet of the downstream thread rolling station to perform physical environmental purification operations to eliminate interference from fluid deposits on sensor monitoring.

[0032] The state reconstruction module triggers a pneumatic purging device to remove cold heading and stretching oil, resulting in a clean fastener surface. The state reconstruction module then activates a dual-color infrared thermometer to acquire dual-band radiation intensity. It calculates the actual residual temperature using a quotient calculation algorithm, subtracts the actual residual temperature from the preset ambient reference temperature to obtain the residual temperature rise deviation, and calls the state vector construction formula to combine the residual temperature rise deviation with the aforementioned deformation energy deviation to generate a thermomechanical coupling state vector. This achieves state fusion of the deformation energy deviation and the residual temperature rise deviation, and simultaneously stores the thermomechanical coupling state vector in the system cache to form a historical state vector.

[0033] During the time period preceding the thread rolling process, the parameter feedforward module is applied within the thread rolling machine's controller. Based on the unique fastener address, it reads the thermomechanical coupling state vector from the system cache and performs decoupling operations on this vector. The parameter feedforward module obtains the thermomechanical coupling state vector, calls the parameter feedforward formula, and calculates the output control vector based on the system's built-in parameters, converting the accumulated upstream process deviations into compensation commands at the machine tool's lower level.

[0034] The parameter feedforward module superimposes the output control vector with the basic setting parameters pre-stored at the bottom of the thread rolling machine to generate the final control signal. The parameter feedforward module controls the feed servo driver based on the final control signal, updates the motion planning trajectory of the feed servo driver in real time, drives the rolling die to adapt to the characteristics of the current fastener and executes the processing action.

[0035] During the synchronous cycle of the rolling die applying mechanical load to the fastener, the reverse calibration module is applied to the downstream thread rolling station to execute closed-loop monitoring logic. The reverse calibration module collects the transient voltage and current of the thread rolling machine spindle drive, calls the power calculation algorithm to extract the actual forming impedance, characterizes the changing state of mechanical load during the rolling process, and identifies continuous systematic deviations when the absolute difference between the impedance sequence mean and the preset theoretical impedance reference value is greater than a preset threshold.

[0036] The reverse calibration module calls the matrix update formula, combines the historical state vector with the preset control channel weight vector to calculate the updated compensation matrix, performs reverse iterative calculation on the feedforward compensation matrix in the parameter feedforward module, and overwrites the feedforward compensation matrix with the updated compensation matrix, thus completing the real-time monitoring and control of the industrial automation production line.

[0037] See appendix Figure 2 The present invention also provides a method for real-time monitoring and control of an automated production line for precision fasteners, comprising the following steps: S1, the energy extraction module is applied to the first cold heading station of the automated synchronous conveyor production line. When the cold heading die of the first cold heading station of the automated synchronous conveyor production line contacts the end face of the wire, the energy extraction module determines the angular displacement of the cold heading machine servo spindle corresponding to the contact moment as the starting angular displacement.

[0038] When the cold heading die returns and detaches from the wire, the energy extraction module determines the angular displacement of the cold heading machine servo spindle corresponding to the detachment moment as the termination angular displacement. During the plastic forming time period from the initial angular displacement to the termination angular displacement, the energy extraction module synchronously collects the spindle operating parameters of the cold heading machine servo of the automated synchronous conveyor production line, which reflect the plastic forming state of the fastener, through an absolute encoder and a dynamic torque sensor configured on the first cold heading station of the automated synchronous conveyor production line, and generates a torque angular displacement sequence.

[0039] The spindle operating parameters include the spindle angular displacement and the transient torque that corresponds synchronously with the spindle angular displacement.

[0040] The energy extraction module obtains the transient torque function based on the torque-angular displacement sequence, and uses the energy integration formula to integrate the torque-angular displacement sequence to obtain the actual plastic deformation energy absorbed by the fastener in the irreversible plastic deformation stage.

[0041] The energy extraction module subtracts the actual plastic deformation energy from the preset benchmark energy consumption to obtain the deformation energy deviation, which characterizes the degree of cold work hardening inside the fastener. The energy extraction module assigns a unique fastener address to the currently processed fastener in the main control shift register and stores the deformation energy deviation in the unique fastener address, so that it moves to the next process synchronously with the physical fastener.

[0042] S2, the state reconstruction module is applied at the feed inlet of the downstream thread rolling station. When the fastener is conveyed to the feed inlet of the thread rolling station by the stepper clamp, the state reconstruction module triggers the pneumatic blowing device to physically blow away the cold heading and stretching oil adhering to the surface of the fastener during the process flow, generating a clean fastener surface with stable infrared radiation characteristics.

[0043] Within the synchronization window after purging is completed, the state reconstruction module activates a dual-color infrared thermometer to measure the surface of the cleaned fastener, obtaining the dual-band radiation intensity of the surface. The state reconstruction module uses a quotient calculation algorithm to perform a division inversion calculation on the dual-band radiation intensity to obtain the actual residual temperature that reduces or removes the influence of the absolute emissivity fluctuation of the surface. The state reconstruction module subtracts the actual residual temperature from the preset ambient reference temperature to obtain the residual temperature rise deviation.

[0044] Based on the unique fastener address of the current fastener, the state reconstruction module reads the deformation energy deviation corresponding to the unique fastener address from the master control shift register. The state reconstruction module calls the state vector construction formula to combine the residual temperature rise deviation and the deformation energy deviation in spatial dimension to generate a thermo-mechanical coupling state vector stripped of environmental interference. At the same time, the state reconstruction module writes the thermo-mechanical coupling state vector into the system cache with the unique fastener address as the index to form a historical state vector.

[0045] S3, the parameter feedforward module is applied within the controller of the thread rolling machine. During the response window before the thread rolling machine performs the rolling action, the parameter feedforward module reads the corresponding thermomechanical coupling state vector from the system cache based on the unique fastener address of the current fastener.

[0046] During the initial operation phase, the feedforward compensation matrix is ​​set to the initial compensation matrix obtained through trial machining of standard fasteners. In subsequent operation phases, the parameter feedforward module utilizes the system's built-in current state... The feedforward compensation matrix for each control iteration cycle is used to perform a linear transformation and decoupling calculation on the thermo-mechanical coupling state vector by calling the parameter feedforward formula, thereby realizing the decoupling mapping of the thermo-mechanical coupling effect and obtaining the output control vector.

[0047] The parameter feedforward module superimposes the output control vector with the basic setting parameters pre-stored at the bottom of the thread rolling machine to obtain the final control signal. Based on the final control signal, the parameter feedforward module controls the feed servo driver, which drives the rolling die to complete the thread processing action of the current fastener according to the feed correction command and the pressure holding correction command.

[0048] S4, the reverse calibration module is applied to the downstream thread rolling station. During the actual rolling process of the fastener by the rolling die, the reverse calibration module collects the transient voltage and current of the thread rolling machine spindle drive in real time. It calls the power calculation algorithm to multiply and sum the transient voltage and current of each phase obtained synchronously from the transient voltage and current, and then filters the result to obtain the total transient power. Finally, it subtracts the total transient power from the pre-calibrated no-load running power under the same speed or the same motion trajectory to obtain the forming load power used for fastener forming.

[0049] The reverse calibration module extracts the actual forming impedance based on the correspondence between the forming load power and the preset actual metal forming mechanical resistance. The reverse calibration module repeatedly samples the fasteners that are being processed continuously and calculates the mean value to obtain the impedance sequence mean value. When the absolute difference between the impedance sequence mean value and the preset theoretical impedance benchmark value is greater than the preset threshold, the reverse calibration module retrieves the historical state vector corresponding to each fastener cached by the system.

[0050] The reverse calibration module calls the matrix update formula and performs reverse correction calculation on the feedforward compensation matrix based on the actual forming impedance, the preset control channel weight vector, and the historical state vector to obtain the updated compensation matrix. The reverse calibration module overwrites the feedforward compensation matrix with the updated compensation matrix, so that the updated compensation matrix participates in the fastener feedforward processing solution as the feedforward compensation matrix in the next control iteration cycle, and finally completes the real-time monitoring and control of the industrial automation production line.

[0051] See appendix Figure 3 In this embodiment, the energy extraction module includes a synchronous acquisition unit, an energy calculation unit, and a deviation binding unit. Through the coordinated operation of these units, it transforms the discrete physical and mechanical quantities of the fastener cold heading stage into data objects that can be tracked across processes. The specific implementation process includes: S110, the synchronous acquisition unit establishes the acquisition range based on the operating status of the cold heading machine. When the cold heading die of the first cold heading station of the automated synchronous conveyor line contacts the end face of the wire, the synchronous acquisition unit determines the angular displacement of the cold heading machine servo spindle corresponding to the contact moment as the starting angular displacement; when the cold heading die returns and leaves the wire, the synchronous acquisition unit determines the angular displacement of the cold heading machine servo spindle corresponding to the departure moment as the ending angular displacement.

[0052] During the plastic forming time period from the initial angular displacement to the final angular displacement, the synchronous acquisition unit synchronously acquires the spindle operating parameters of the cold heading machine servo, which reflect the plastic forming state of the fastener, through an absolute encoder and a dynamic torque sensor configured on the first cold heading station of the automated synchronous conveyor production line, and generates a torque angular displacement sequence. The spindle operating parameters include the spindle angular displacement and the transient torque synchronously corresponding to the spindle angular displacement.

[0053] During this data collection process, the cold heading stage is a stage in which the material undergoes drastic plastic rheology. The transient torque output by the spindle can characterize the change in forming resistance of the metal material during the cold heading plastic flow process.

[0054] To ensure real-time acquisition and accurate data alignment, the synchronous acquisition unit utilizes a distributed clock mechanism based on an industrial Ethernet bus to ensure that the data sampling timestamps of the absolute encoder and the dynamic torque sensor are consistent.

[0055] For the hardware installation and high-frequency signal extraction of absolute encoders and dynamic torque sensors, those skilled in the art can perform conventional flange or shaft end configuration based on the mechanical transmission structure of the cold heading machine servo. The conventional synchronous acquisition and digital-to-analog conversion mechanism of its electrical signals are well-known technologies in this field and will not be elaborated here.

[0056] S120, the energy calculation unit acquires the generated torque-angular displacement sequence, and obtains the transient torque function based on this sequence. In the process of fitting the transient torque function, the discrete torque and angular displacement sampling points in the torque-angular displacement sequence are transformed into a continuous curve mapping relationship. The specific fitting calculation process is implemented using the conventional least squares polynomial curve fitting algorithm.

[0057] After obtaining the transient torque function, the energy calculation unit uses the energy integration formula to integrate the torque-angular displacement sequence, thus obtaining the actual plastic deformation energy absorbed by the fastener during the irreversible plastic deformation stage. The energy integration formula is as follows: ; In the formula: This represents the actual plastic deformation energy. The symbol for definite integral; This is the initial angular displacement; This is the termination angular displacement; It is a transient torque function; It is a differential operator; This represents the angular displacement variable.

[0058] Actual plastic deformation energy reflects the actual mechanical work dissipated by fasteners during cold heading plastic deformation and macro-working hardening. Through the calculation of the energy integral formula, the energy calculation unit maps the complex nonlinear torque fluctuation curve into a single energy characteristic scalar, providing a computational basis for the lightweight storage of subsequent data and cross-process feedforward.

[0059] S130, the deviation binding unit obtains the calculated actual plastic deformation energy, subtracts this actual plastic deformation energy from the preset reference energy consumption, and obtains the deformation energy deviation characterizing the degree of cold work hardening inside the fastener. .

[0060] The preset benchmark energy consumption is set based on the average mechanical work consumed by qualified wire of standard material to complete the calibration cold heading action under the same process parameters. For example, for a certain batch of titanium alloy fastener cold heading process, the benchmark energy consumption is usually set between 1200J and 1500J.

[0061] Under normal circumstances, deformation energy deviation It exhibits a distribution pattern centered on zero, with positive values ​​indicating a high degree of hardening of the current fastener and negative values ​​indicating a low degree of hardening.

[0062] To ensure spatiotemporal synchronization between the underlying data stream and the physical entity's spatial location, the deviation binding unit assigns a unique fastener address to the currently processed fastener in the master control shift register, establishing a physical mapping relationship between the data link and the production line station. Subsequently, the deviation binding unit deviates the deformation energy... The unique fastener address is stored, and it is moved to the next process synchronously with the physical fastener as a digital tag.

[0063] The address allocation and follow-up shift control of the master shift register can be implemented by those skilled in the art based on the built-in data shift instruction block of the field programmable logic controller. The method of synchronously shifting the memory array address with the physical station cycle is a well-known technology in the field and will not be described in detail here.

[0064] See appendix Figure 4 In this embodiment, the state reconstruction module includes an environmental purification unit, an anti-interference temperature measurement unit, and a state fusion unit. Through the coordinated operation of these units, it isolates environmental interference during the cross-process transfer of fasteners and fuses it with historical deformation characteristics. The specific implementation process includes: S210, the environmental purification unit relies on the position detection sensor configured on the feed port side to monitor the position of the fastener in real time. When the fastener is conveyed to the feed port of the thread rolling station by the stepping clamp and the position signal is triggered, the environmental purification unit triggers the pneumatic blowing device to physically blow away the cold heading and stretching oil adhering to the surface of the fastener during the process flow, generating a clean fastener surface with stable infrared radiation characteristics.

[0065] Fasteners typically require a cold heading oil coating for lubrication and cooling during the cold heading stage. When these fluid oil films enter the downstream station, they can alter the infrared emissivity of the fastener's metal matrix and cause subsequent temperature measurement distortion.

[0066] The actuator of the pneumatic purging device can be an industrial flat nozzle, an annular nozzle, or other jet elements that can form a directional high-speed airflow; the control circuit of the pneumatic purging device can be matched with a high-speed response solenoid valve to ensure that the purging action is synchronized with the fastener positioning signal.

[0067] At the moment the fastener reaches the predetermined detection space position, the pneumatic purging device sprays high-pressure clean air to peel off the fluid oil film on the metal surface. The purging action of the pneumatic purging device eliminates the attenuation and scattering interference of the fluid medium on the infrared radiation signal, exposes the metal substrate, and generates a clean fastener surface with stable infrared radiation characteristics.

[0068] S220, after the environmental purification unit cleans the surface of the fastener, the anti-interference temperature measurement unit starts the dual-color infrared thermometer to measure the surface of the cleaned fastener within the temperature measurement synchronization window when the pneumatic purging device has completed purging and the fastener has not yet left the measurement field of view of the dual-color infrared thermometer, and obtains the dual-band radiation intensity of the surface of the cleaned fastener.

[0069] The dual-color infrared thermometer is equipped with photoelectric detection channels that are sensitive to two different but similar infrared wavelengths. It can simultaneously acquire the electrical signal amplitude corresponding to these two independent wavelengths, i.e., the dual-band radiation intensity. Subsequently, the anti-interference temperature measurement unit uses the quotient calculation algorithm to perform phase division inversion calculation on the dual-band radiation intensity to obtain the actual residual temperature that reduces or removes the influence of fluctuations in the absolute emissivity of the surface.

[0070] The quotient calculation algorithm is based on the premise that the attenuation of radiation energy in two similar wavelength bands is proportionally equal to the interference from the surface roughness or thin oxide layer of the measured object. The algorithm divides the collected radiation intensity values ​​of these two bands, and the resulting quotient reduces the impact of fluctuations in the absolute surface emissivity on the temperature measurement results while retaining the ratio information that is monotonically correlated with the true temperature of the object. Based on this quotient, the actual residual temperature can be obtained by referring to the pre-calibrated temperature inversion curve of the dual-color infrared thermometer.

[0071] The temperature inversion curve is obtained by fitting a data table or polynomial through a multi-temperature gradient calibration test performed in a standard blackbody radiation furnace.

[0072] Next, the anti-interference temperature measurement unit subtracts the actual residual temperature from the preset ambient reference temperature to obtain the residual temperature rise deviation. .

[0073] The ambient reference temperature is set based on the ambient temperature background of the processing workshop. For example, the ambient reference temperature of the workshop is set to a constant value of 25°C, or the temperature of the metal structure base of the wire rolling machine bed is collected in real time by a temperature sensor as the ambient reference temperature.

[0074] The subtraction operation eliminates the influence of the ambient baseline heat, resulting in a residual temperature rise deviation. The net heat load carried by the fastener during the thread rolling process after the fastener has undergone severe deformation and heat generation during cold heading and dissipated heat through spatial circulation is quantified.

[0075] S230, the state fusion unit acquires the residual temperature rise deviation obtained by the anti-interference temperature measurement unit. Based on the unique fastener address of the current fastener, the deformation energy deviation corresponding to that unique fastener address is read from the master control shift register. .

[0076] The state fusion unit calls the state vector construction formula to address the residual temperature rise deviation. and the deformation energy deviation By combining spatial dimensions, a thermomechanical coupling state vector stripped of environmental interference is generated. The formula for constructing the state vector is: ; In the formula: This represents the thermo-mechanical coupling state vector; This is the deformation energy deviation; This represents the residual temperature rise deviation.

[0077] The continuous step-by-step conveying of industrial automated production lines requires physical materials and digital information to be aligned. The status fusion unit uses a unique fastener address as an index identifier to complete the spatial convergence of heterogeneous data.

[0078] Deformation energy deviation reflects the cold work hardening resistance of the internal lattice structure of the fastener, while residual temperature rise deviation reflects the thermal softening effect of the material under the action of a thermal field. The thermomechanical coupling state vector generated by the combination of the two in the spatial dimension This characterizes the comprehensive physical resistance of fasteners at the moment they enter the thread rolling process.

[0079] Combined generation of thermo-mechanical coupling state vector Subsequently, the state fusion unit simultaneously couples the thermodynamic state vector. The system cache is written with the unique fastener address as the index. This thermomechanical coupling state vector is used as the reading object of the parameter feedforward module in the current processing cycle, and participates in the subsequent matrix adaptive calculation as the historical state vector after the current fastener is processed.

[0080] The thermomechanical coupling state vector containing comprehensive physical resistance characteristics is solidified into a historical state vector for storage, providing traceable physical parameter samples for subsequent closed-loop iteration and macroscopic wear calibration of the system.

[0081] For the retention and retrieval of system cached data, those skilled in the art can use the in-memory database or key-value storage architecture inside the industrial control computer to implement it, which is a well-known technology in the field and will not be described in detail here.

[0082] See appendix Figure 5 In this embodiment, the parameter feedforward module includes a feedforward calculation unit and a dynamic execution unit. Through the coordinated operation of these units, it converts the physical state deviations transmitted from upstream processes into real-time machine tool control compensation commands. The specific implementation process includes: S310, the feedforward calculation unit is applied in the controller of the thread rolling machine. During the response window before the thread rolling machine performs the rolling action, the feedforward calculation unit reads the corresponding thermomechanical coupling state vector from the system cache based on the unique fastener address of the current fastener. .

[0083] The response window period refers to the time interval between the fastener falling into the feed slide of the thread rolling machine and the start of the rolling die sliding. This time interval is determined by the phase difference of the mechanical cam and is usually 20ms to 50ms.

[0084] In the initial operation phase when the system is just started and the reverse calibration module has not yet triggered matrix feedback, since sufficient processing feedback data has not yet been accumulated, the feedforward calculation unit sets the feedforward compensation matrix to the dimension-matched initial compensation matrix. This initial compensation matrix is ​​obtained through standard fastener trial processing calibration, or it is set to a zero matrix when initial compensation is not enabled, so that the output control vector is zero, avoiding the introduction of uncalibrated intervention deviations in the initial state.

[0085] After the matrix adaptive unit generates the updated compensation matrix and overwrites the feedforward compensation matrix, the system enters the non-initial operation phase. The feedforward solution unit utilizes the system's built-in current state... The feedforward compensation matrix for each control iteration cycle The parameter feedforward formula is called to apply this to the thermodynamic coupling state vector. Perform linear transformation decoupling calculations.

[0086] The deformation energy deviation and residual temperature rise deviation within the thermomechanical coupling state vector have complex cross-interferences on the final thread forming quality. This is addressed through a feedforward compensation matrix. The linear mapping can achieve the decoupling mapping of thermomechanical coupling effects, resulting in the output control vector for execution by the underlying hardware. The feedforward formula for this parameter is: ; In the formula: This is the output control vector; Currently in the th The feedforward compensation matrix for each control iteration cycle; This is the thermo-mechanical coupling state vector.

[0087] In terms of data structure, the output control vector It is represented as a two-dimensional column vector, with each row element corresponding to a feed correction command. With pressure holding correction command The numerical value.

[0088] S320, the dynamic execution unit obtains the output control vector from the feedforward calculation unit. The output control vector The final control signal is obtained by superimposing the pre-stored basic setting parameters at the bottom layer of the thread rolling machine.

[0089] The basic setting parameters are set based on the theoretical machining parameters required for a standard qualified fastener blank under the current thread specification. For example, for the machining of M6 thread, the basic setting parameters usually set the theoretical feed rate to 30mm / s and the theoretical holding time to 0.2s.

[0090] Dynamic execution unit extracts output control vector Feed correction instructions With pressure holding correction command The theoretical feed rate and theoretical holding time in the basic setting parameters are algebraically added to generate a final control signal customized for the current fastener. Subsequently, the dynamic execution unit controls the feed servo drive based on the final control signal.

[0091] The feed servo driver receives the updated trajectory planning parameters and drives the rolling die to complete the thread processing action of the current fastener according to the feed correction command and the pressure holding correction command.

[0092] If the fastener hardness is too high and the temperature is too low from the upstream, the final control signal will usually tend to reduce the feed speed of the rolling die and extend the holding time to reduce the probability of die breakage or incomplete tooth profile.

[0093] For the underlying pulse distribution and closed-loop position control of the feed servo drive, those skilled in the art can use the standard industrial servo control bus protocol for configuration. Its multi-axis synchronization and interpolation motion control logic is a well-known technology in the field and will not be described in detail here.

[0094] See appendix Figure 6 In this embodiment, the reverse calibration module includes an impedance extraction unit and a matrix adaptive unit. Through the coordinated operation of these units, it transforms macroscopic physical wear and system process deviations into reverse iterative parameters for the machine tool control model. The specific implementation process includes: S410, during the actual rolling process of the fastener by the rolling die, the impedance extraction unit collects the transient voltage and current of the thread rolling machine spindle drive in real time.

[0095] At the hardware implementation level, the impedance extraction unit uses a high-frequency Hall voltage sensor and a Hall current sensor configured on the AC output side of the spindle drive of the wire rolling machine to extract physical electrical signals and quantize them into digital transient voltage and current through an analog-to-digital conversion circuit.

[0096] The impedance extraction unit calls the power calculation algorithm to multiply and sum the transient voltages and currents of each phase obtained by synchronous sampling in the transient voltage and current, and then filters them to obtain the total transient power. Subsequently, the impedance extraction unit subtracts the total transient power from the pre-calibrated no-load operating power under the same speed or the same motion trajectory to obtain the forming load power used for fastener forming.

[0097] Among them, the no-load running power is the basic power loss of the thread rolling machine when the spindle is driven to maintain the corresponding speed or corresponding motion trajectory in the absence of material. Its value is collected and stored in the system through no-load test during the equipment initialization stage, or read from the no-load power calibration table according to the real-time spindle speed.

[0098] After obtaining the forming load power, the impedance extraction unit extracts the actual forming impedance based on the calculated forming load power and the preset correspondence between the actual metal forming mechanical resistance.

[0099] Among them, the actual mechanical resistance of metal forming is the reaction force parameter that reflects the plastic extrusion of the die on the metal blank; the corresponding relationship is a numerical mapping model established based on the mechanical transmission efficiency, reduction ratio and rolling speed of the machine tool spindle transmission chain; the rolling speed refers to the actual relative linear motion speed of the rolling die when it performs thread extrusion forming on the fastener blank. This rolling speed is calculated in real time by the impedance extraction unit based on the real-time working speed of the thread rolling machine spindle driver and the pre-configured kinematic parameters of the thread rolling machine transmission mechanism.

[0100] In terms of specific extraction and execution logic, the impedance extraction unit inputs the calculated forming load power into the numerical mapping model. The model uses internal conversion logic to offset the mechanical transmission loss caused by transmission efficiency and reduction ratio, and combines the rolling line speed to convert the power on the electrical side into the mechanical quantity on the mechanical side. This allows for the reverse deduction of the actual metal forming mechanical resistance generated by the fastener on the rolling die under the current deformation state. Finally, the deduced actual metal forming mechanical resistance is normalized and converted in combination with the rolling line speed to obtain the actual forming impedance characterizing the current fastener rolling forming load strength.

[0101] The impedance extraction unit repeatedly samples the fasteners that are being processed continuously, and continuously extracts each actual forming impedance.

[0102] For the industrial configuration of high-frequency Hall voltage sensors and Hall current sensors, as well as the routine calculation of transient power, those skilled in the art can use the communication interface inside standard electrical instruments or frequency converters to read parameters. The acquisition mechanism of electrical data is a well-known technology in this field and will not be described in detail here.

[0103] S420, the matrix adaptive unit acquires each actual formed impedance extracted by the impedance extraction unit. The matrix adaptive unit calculates the continuous... The average value of the actual forming impedance of each fastener is used to obtain the average value of the impedance sequence.

[0104] When the absolute difference between the mean of the impedance sequence and the preset theoretical impedance reference value is greater than the preset threshold, the matrix adaptive unit retrieves the historical state vectors corresponding to each fastener cached by the system.

[0105] in, This represents the sliding window capacity, which is set based on the statistical confidence interval of process fluctuations. For example, the sliding window capacity is usually set to an integer between 10 and 50 to filter out random hardware noise in individual piece processing and preserve the macroscopic deviation trend of the system. The theoretical impedance reference value is set based on the standard forming mechanics model of the current thread specification and material hardness under ideal working conditions. For example, when machining alloy steel fasteners, the theoretical impedance reference value is set to 500 N·s / m to 800 N·s / m. The preset threshold is set based on the maximum impedance fluctuation tolerance allowed by the engineering quality, for example, the preset threshold is set to 50 N·s / m.

[0106] When the absolute difference is not greater than the preset threshold, the system determines that the current process is in a stable range and the feedforward compensation matrix remains unchanged.

[0107] When the absolute difference exceeds the preset threshold, it indicates that the machine tool in the automated synchronous conveyor production line has experienced macroscopic degradation such as mold wear or material batch hardness shift. The matrix adaptive unit calls the matrix update formula based on the actual forming impedance and the preset control channel weight vector. And this historical state vector, for the feedforward compensation matrix inside the feedforward solution unit. Perform reverse correction calculations to obtain the updated compensation matrix. The formula for updating this matrix is: ; In the formula: This represents updating the compensation matrix; The feedforward compensation matrix represents the current iteration cycle; Represents the error convergence factor; Represents the capacity of the sliding window; Represents the summation symbol; Representing the The actual forming resistance of a fastener; This represents the preset theoretical impedance reference value; This represents the preset control channel weight vector; Representing the The transpose of the historical state vector corresponding to each fastener.

[0108] Among them, the error convergence factor It is an empirical coefficient that controls the size of the matrix correction step each time, usually set to 0.01 to 0.05 to ensure the numerical stability of the iterative calculation; Control channel weight vector It is a column vector pre-defined based on the sensitivity of the feed axis and holding action to the final impedance change, and its dimensions are the same as the output control vector. The dimensions are consistent, and it is used to allocate the actual molding impedance deviation to the control channels corresponding to the feed correction command and the holding pressure correction command.

[0109] The matrix adaptive unit updates the compensation matrix. Overwrite the feedforward compensation matrix inside the feedforward solution unit This allows the updated compensation matrix to participate as a feedforward compensation matrix in the fastener feedforward machining solution in the next control iteration cycle, ultimately achieving real-time monitoring and control of the industrial automated production line.

[0110] To further aid in understanding the technical solution of this invention, the following application example is given in conjunction with a specific application scenario of an industrial automated production line that produces M6 high-strength alloy steel fasteners.

[0111] In an automated production line for M6 high-strength alloy steel fasteners with a standard operating speed of 120 pieces / min, the system performed the following real-time monitoring and control process for a fastener labeled #1052 that was being processed.

[0112] During the cold heading stage, the energy extraction module monitors the contact between the cold heading die and the wire at the first cold heading station. Within the set plastic forming time period from the initial angular displacement to the final angular displacement, the synchronous acquisition unit acquires the transient torque output by the servo spindle of the cold heading machine and fits a continuous transient torque function.

[0113] The energy calculation unit performs definite integration within the effective angular displacement range using the energy integration formula, and calculates that the actual plastic deformation energy absorbed by the #1052 fastener is 610J.

[0114] The deviation binding unit subtracts the calculated actual plastic deformation energy from the pre-set reference energy consumption of 600J for this batch of M6 alloy steel wire to obtain the deformation energy deviation. A value of 10J indicates that the degree of localized work hardening at the end of the wire is slightly higher than the standard value. This deformation energy deviation... It is stored in the memory space bound to the unique fastener address #1052 in the master shift register.

[0115] Subsequently, the stepping clamp conveys the fastener to the feed inlet of the downstream thread rolling station. After the positioning detection sensor triggers the positioning signal, the state reconstruction module controls the pneumatic purging device to remove the cold heading and stretching oil from the surface.

[0116] Within the temperature measurement synchronization window after the pneumatic purging device has completed purging and the fastener has not yet left the measurement field of view, the dual-color infrared thermometer measures the actual residual temperature of the surface to be 30℃. Since the system ambient reference temperature is set to a constant value of 25℃, the residual temperature rise deviation is obtained by subtracting this value from the state reconstruction module. The temperature is 5℃. Next, the state fusion unit retrieves the deformation energy deviation based on the unique fastener address. Generate the thermo-mechanical coupling state vector It is then written to the system cache as the historical state vector of the fastener.

[0117] Before the thread rolling machine prepares for rolling, the feedforward calculation unit of the parameter feedforward module reads the thermo-mechanical coupling state vector from the system cache. At this point, the system is in a non-initial operation phase; assuming it is currently in the [number]th [stage / phase]... The feedforward compensation matrix for each control iteration cycle for The feedforward solution unit calls the parameter feedforward formula. Perform linear transformation decoupling calculations, i.e. The output control vector is calculated. .

[0118] Among them, the feed correction command -2.0 mm / s, pressure holding correction command The time is 0.2s. The dynamic execution unit will output the control vector. The final control signal is generated by superimposing the theoretical feed rate of 30 mm / s and the theoretical holding time of 0.2 s stored in the system.

[0119] Driven by this final control signal, the feed servo driver corrects the feed speed to 28 mm / s and the holding time to 0.4 s. This dynamic adjustment compensates for the impact of excessive hardening and residual heat on the forming quality of the fasteners.

[0120] During the rolling process, the impedance extraction unit of the reverse calibration module collects the transient voltage and transient current of each phase, and obtains the total transient power by multiplying, summing, and filtering. The system reads the no-load operating power from the no-load power calibration table based on the real-time spindle speed and performs a subtraction operation to obtain the forming load power.

[0121] The impedance extraction unit extracts the actual forming impedance based on a numerical mapping model. When the matrix adaptive unit detects 20 consecutive fasteners (sliding window capacity...),... The impedance sequence mean is 660 N·s / m, while the theoretical impedance reference value is 600 N·s / m, the absolute difference of 60 N·s / m is greater than the preset threshold of 50 N·s / m.

[0122] The matrix adaptive unit identifies the deviation caused by mold wear, calls the matrix update formula for calculation, and sets the error convergence factor. Control channel weight vector The matrix correction is obtained by summing the impedance deviations and weight vectors of the 20 fasteners with the transpose of the historical state vectors. Finally, the updated compensation matrix... The feedforward compensation matrix inside the feedforward solution unit was overwritten, enabling subsequent processing to dynamically offset die wear.

[0123] To verify the effectiveness of the above solution, the applicant conducted a comparative experiment on 5000 pieces of M6 alloy steel wire under full load. The experimental group used the real-time monitoring and control system provided by this invention, while the control group used a traditional fixed parameter control scheme. The forming accuracy was evaluated by detecting the fluctuation deviation of the thread pitch diameter of the fasteners online. The experimental results are shown in the appendix. Figure 7 .

[0124] See appendix Figure 7 , Figure 7 The solid lines with circular markings represent the dynamic control scheme of this invention, while the dashed lines with triangular markings represent the traditional fixed-parameter control scheme.

[0125] From the appendix Figure 7 It is evident that within the first 2500 pieces of the processing batch, the thread pitch diameter fluctuation deviation of both schemes remained within the range of approximately 0 μm. As the processing quantity exceeded 2500 pieces, due to the accumulation of micro-wear on the mold and fluctuations in the physical properties of the wire, the dashed line corresponding to the traditional fixed-parameter control scheme began to show a significant non-linear upward movement, and the fluctuations between each sampling point were severe. By the time the batch reached 5000 pieces, the thread pitch diameter fluctuation deviation had approached 40 μm, affecting product consistency.

[0126] In contrast, the solid line corresponding to the dynamic control scheme of this invention remained stably near the 0μm axis throughout the entire cycle of 5000 pieces. This proves that the invention, through multi-dimensional state reconstruction of deformation energy and residual temperature rise, combined with dynamic correction of the compensation matrix based on molding impedance feedback, can effectively reduce the impact of cross-process physical variables and mold wear, and improve the real-time monitoring and control accuracy of industrial production lines.

Claims

1. A real-time monitoring and control system for an automated production line of precision fasteners, characterized in that, include: The energy extraction module is used to collect the spindle operating parameters, call the energy integration formula to obtain the actual plastic deformation energy and convert it into deformation energy deviation; The state reconstruction module is used to obtain the residual temperature rise deviation based on the collected dual-band radiation intensity using a quotient calculation algorithm, and then call the state vector construction formula to combine the residual temperature rise deviation and the deformation energy deviation into a thermo-mechanical coupled state vector. The parameter feedforward module is used to call the parameter feedforward formula, process the thermo-mechanical coupling state vector based on the system's built-in feedforward compensation matrix to obtain the output control vector, and control the feed servo drive. The reverse calibration module is used to collect the transient voltage and current of the spindle drive of the wire rolling machine, call the power calculation algorithm to extract the actual forming impedance and calculate the impedance sequence mean. When the absolute difference between the impedance sequence mean and the preset theoretical impedance benchmark value is greater than the preset threshold, the matrix update formula is called to update the feedforward compensation matrix. The energy extraction module includes a synchronous acquisition unit and an energy calculation unit; The synchronous acquisition unit determines the starting angular displacement and the ending angular displacement based on the operating status of the cold heading machine servo. During the time period from the starting angular displacement to the ending angular displacement, the synchronous acquisition unit synchronously acquires the spindle operating parameters through an absolute encoder and a dynamic torque sensor configured on the first cold heading station of the automated synchronous conveyor production line, and generates a torque angular displacement sequence. The energy calculation unit obtains the transient torque function based on the torque angular displacement sequence, calls the energy integration formula, integrates the transient torque function, and obtains the actual plastic deformation energy. The energy extraction module also includes a deviation binding unit; The deviation binding unit is used to subtract the actual plastic deformation energy from the preset benchmark energy consumption to obtain the deformation energy deviation. The deviation binding unit allocates a unique fastener address in the master control shift register and stores the deformation energy deviation into the unique fastener address. The benchmark energy consumption is preset based on the average mechanical work consumed by qualified wire of standard material to complete the calibrated cold heading action under the same process parameters; The state reconstruction module includes an environmental purification unit and an anti-interference temperature measurement unit; When the fastener is conveyed to the feed port by the stepper clamp, the environmental purification unit is used to trigger the pneumatic blowing device to physically blow the surface of the fastener, remove the cold heading and stretching oil on the surface of the fastener, and produce a clean fastener surface. Within the synchronization window after purging is completed, the anti-interference temperature measurement unit activates a dual-color infrared thermometer to measure the surface of the cleaned fastener and obtain the dual-band radiation intensity. The state reconstruction module also includes a state fusion unit; The anti-interference temperature measurement unit uses the quotient calculation algorithm to perform phase division inversion calculation on the dual-band radiation intensity to obtain the actual residual temperature; The residual temperature deviation is obtained by subtracting the actual residual temperature from the preset environmental reference temperature. Based on the unique fastener address, the corresponding deformation energy deviation is read, the state vector construction formula is called, the residual temperature rise deviation and the deformation energy deviation are combined in terms of spatial dimension to generate the thermo-mechanical coupling state vector, and the thermo-mechanical coupling state vector is written into the system cache to form a historical state vector; The ambient reference temperature is preset based on the ambient temperature background of the processing workshop; the parameter feedforward module includes a feedforward calculation unit. During the response window period before the rolling action is performed by the thread rolling machine in the automated synchronous conveyor production line, the feedforward calculation unit reads the corresponding thermomechanical coupling state vector from the system cache based on the unique fastener address. The feedforward calculation unit calls the parameter feedforward formula to perform a linear transformation calculation on the feedforward compensation matrix and the thermomechanical coupling state vector to obtain the output control vector containing the feed correction command and the pressure holding correction command; The parameter feedforward module also includes a dynamic execution unit; The dynamic execution unit is used to extract the feed correction command and the pressure holding correction command from the output control vector, and perform superposition calculation with the preset basic setting parameters to generate the final control signal. The dynamic execution unit controls the feed servo driver according to the final control signal, refreshes the motion planning trajectory, and drives the rolling die to complete the processing action. The basic setting parameters are preset based on the theoretical processing parameters required for a standard qualified fastener blank under the current thread specification.

2. The real-time monitoring and control system for an automated production line of precision fasteners according to claim 1, characterized in that, The reverse calibration module includes an impedance extraction unit; The impedance extraction unit is used to acquire the transient voltage and current of the spindle drive of the wire rolling machine in real time; The impedance extraction unit calls the power calculation algorithm to multiply and sum the transient voltages and transient currents of each phase obtained by synchronous sampling in the transient voltage and current, and then filter them to obtain the total transient power. The impedance extraction unit subtracts the transient total power from the no-load operating power to obtain the forming load power, converts the forming load power into the actual metal forming mechanical resistance based on the numerical mapping model, and extracts the actual forming impedance by combining the rolling line speed. The no-load operating power is the base power loss of the wire rolling machine when the main shaft is driven to maintain the corresponding speed or corresponding motion trajectory in the absence of material. The value of the no-load operating power is preset by collecting data through no-load testing during the equipment initialization phase.

3. The real-time monitoring and control system for an automated production line of precision fasteners according to claim 2, characterized in that, The reverse calibration module also includes a matrix adaptive unit; The matrix adaptive unit is used to calculate the average value of the actual forming impedance of multiple consecutive fasteners to obtain the average value of the impedance sequence. When the absolute difference between the mean of the impedance sequence and the theoretical impedance reference value is greater than the preset threshold, the matrix adaptive unit retrieves the historical state vector corresponding to each fastener. The number of consecutive fasteners is determined by the sliding window capacity, which is preset based on the statistical confidence interval of process fluctuations. The theoretical impedance reference value is preset based on the standard forming mechanical model of the current thread specification and material hardness under ideal working conditions. The preset threshold is preset based on the maximum impedance fluctuation tolerance allowed by the engineering quality.

4. The real-time monitoring and control system for an automated production line of precision fasteners according to claim 3, characterized in that, The matrix adaptive unit calls the matrix update formula to calculate the updated compensation matrix; The specific calculation of the matrix update formula is as follows: The difference between each actual forming impedance and the theoretical impedance reference value is multiplied by the control channel weight vector and the transpose of the historical state vector and accumulated. The correction amount is obtained by scaling the error convergence factor and the sliding window capacity. The correction amount is then subtracted from the feedforward compensation matrix to obtain the updated compensation matrix. The matrix adaptive unit overwrites the feedforward compensation matrix with the updated compensation matrix to complete the real-time monitoring and control of the industrial automated production line. The error convergence factor is an empirical coefficient that controls the step size of each matrix correction and is preset in advance. The control channel weight vector is preset based on the sensitivity of the feed axis and the pressure holding action to the final impedance change.

Images