Control system of self-lifting profiling taper transfer printing machine

Abstract

The invention discloses a control system of a self-lifting profiling taper transfer printing machine, and relates to the technical field of industrial automatic control and precise transfer printing. And the pressure compensation module is used for carrying out PID (Proportion Integration Differentiation) operation according to the theoretical pressure value of each point on the taper transfer track and the real-time pressure value fed back by the pressure sensor to generate a dynamic pressure compensation instruction so as to keep the transfer pressure constant at different diameters of the conical workpiece. Through the dynamic pressure adjusting module, a pressure planning value is inquired in real time according to the curvature radius of a transfer printing point, PID closed-loop control is carried out in combination with feedback of a pressure sensor, and dynamic self-adaptive constant adjustment of transfer printing pressure at different diameters of a conical workpiece is achieved; therefore, the process problems of different transfer printing depths, local loss or ink overflow and the like caused by pressure fluctuation are effectively solved, and the uniformity and consistency of transfer printing quality are remarkably improved.

Description

A control system for a self-lifting contour tapered transfer machine Technical Field

[0001] This invention relates to the field of industrial automation control and precision transfer technology, and in particular to a control system for a self-lifting contour tapered transfer machine. Background Technology

[0002] With the increasing demands for exquisite and personalized product appearance from industries such as consumer electronics, high-end packaging, and automotive interiors, the need for high-precision pattern and marking transfer on complex geometric surfaces such as conical and curved surfaces is becoming increasingly urgent. This demand tightly couples industrial automation control technology with precision transfer technology, driving manufacturing processes towards intelligence and flexibility. Traditional planar or fixed-path transfer methods can no longer meet the stringent standards of fit to complex curved surfaces, ink layer uniformity, and batch consistency. Therefore, developing intelligent transfer systems that can adapt to the three-dimensional shape of workpieces and achieve precise dynamic process control has become an important direction for the evolution of this interdisciplinary technology field.

[0003] In current technological practices, the integration of industrial automation control and precision transfer printing technology still faces challenges. On the one hand, while general-purpose motion control platforms (such as multi-axis robots) possess flexible trajectory planning capabilities, their end effectors lack dedicated closed-loop adjustment mechanisms for transfer process characteristics (such as elastic contact and pressure sensitivity), making it difficult to guarantee constant pressure contact and stable ink transfer on surfaces with varying curvature. On the other hand, although specialized transfer printing equipment is optimized for specific workpieces in terms of mechanical structure, its control systems are mostly simple sequential logic or open-loop contouring, lacking sufficient automation. They rely on operator experience for parameter tuning and compensation, failing to achieve online process optimization and quality control based on real-time sensor feedback. These two technological approaches have not yet achieved deep integration and synergy.

[0004] The core problem with existing technologies lies in the failure to achieve unified system-level modeling and real-time decoupling between the high-precision motion capabilities of industrial automation control and the physical constraints of precision transfer printing processes. Specifically: First, the control system lacks the ability to digitally perceive the workpiece contour online with high precision and to map process-oriented trajectories, leading to deviations between the motion path and optimal transfer contact conditions. Second, when the transfer head dynamically tracks curved surfaces, the lack of an integrated control model that correlates geometric trajectories, pressure settings, and material deformation characteristics causes pressure fluctuations with curvature changes, directly affecting transfer uniformity. Third, the multi-degree-of-freedom motion between the lifting axis, pressure axis, and workpiece rotation axis fails to achieve hard synchronization in terms of timing and dynamic response, resulting in insufficient overall system coordination. This can easily lead to vibration or lag during high-speed operation, hindering further improvements in transfer efficiency and precision.

[0005] Therefore, it is essential to invent a control system for a self-lifting contour tapered transfer machine to solve the above problems. Summary of the Invention

[0006] The purpose of this invention is to provide a control system for a self-lifting contour tapered transfer machine to solve the problems mentioned in the background art.

[0007] To achieve the above objectives, the present invention provides the following technical solution: a control system for a self-lifting contour tapered transfer machine, comprising the following modules:

[0008] The contour data processing module is used to receive and process contour data from the contour sensor and generate a tapered transfer trajectory that matches the surface contour of the tapered workpiece to be transferred.

[0009] An adaptive lifting control module, connected to the contour data processing module and the lifting mechanism drive unit, is used to calculate and generate real-time position commands for the lifting motor based on the tapered transfer trajectory, so as to drive the transfer head to synchronously track the workpiece taper in the vertical direction.

[0010] The dynamic pressure adjustment module, connected to the pressure sensor and the pressure execution unit, is used to perform PID calculations based on the theoretical pressure values ​​at each point on the tapered transfer trajectory and the real-time pressure values ​​fed back by the pressure sensor, to generate dynamic pressure compensation commands to maintain the transfer pressure constant at different diameters of the tapered workpiece.

[0011] The synchronous motion synthesis module is communicatively connected to the contour data processing module, the adaptive lifting control module, and the dynamic pressure adjustment module, respectively. It is used to perform spatiotemporal synchronous coupling of the tapered transfer trajectory, real-time position command, and pressure compensation command to generate the final multi-axis cooperative motion control command, and send it to the lifting mechanism drive unit and the pressure execution unit.

[0012] The process parameter management module is communicatively connected to the contour data processing module and the dynamic pressure adjustment module, and is used to store and manage the transfer process parameter sets corresponding to different workpiece models.

[0013] The technical effects and advantages of this invention are as follows:

[0014] 1. The present invention performs high-precision sampling, fitting and coordinate mapping of the workpiece contour through the contour data processing module, which can automatically generate a digital transfer trajectory that perfectly matches the complex curved surface of the conical workpiece, completely replacing the traditional debugging method that relies on manual experience and mechanical templates, and significantly improving trajectory accuracy and production efficiency.

[0015] 2. The present invention adopts a "feedforward-feedback" composite control strategy through the adaptive lifting control module, combined with real-time trajectory differentiation and position closed-loop PID adjustment, so that the transfer head can quickly and accurately follow the workpiece taper change to perform lifting motion, effectively eliminating tracking lag and position deviation, and ensuring the continuity and accurate alignment of the transfer pattern in the vertical direction.

[0016] 3. The present invention uses the dynamic pressure adjustment module to query the pressure planning value in real time based on the curvature radius of the transfer point, and combines the feedback of the pressure sensor to perform PID closed-loop control, thereby realizing the dynamic adaptive constant adjustment of the transfer pressure at different diameters of the conical workpiece. This effectively overcomes the process problems such as uneven transfer depth, local missing parts or ink overflow caused by pressure fluctuations, and significantly improves the uniformity and consistency of transfer quality.

[0017] 4. This invention establishes and applies the pressure-curvature relationship table through pre-calibration, and digitally correlates and fits the actual process pressure and geometric curvature to obtain the best transfer effect. This enables the system to automatically match the appropriate pressure setting based on the workpiece shape, which greatly improves the scientific nature and repeatability of the process and ensures a high degree of consistency in quality between batches.

[0018] 5. The present invention uses the synchronous motion synthesis module to perform spatiotemporal synchronous coupling and kinematic calculation of trajectory commands, position commands and pressure commands with a unified interpolation cycle, and sends them synchronously through a real-time bus, realizing millisecond-level hard synchronization between lifting motion, pressure adjustment and workpiece rotation, ensuring the stability, smoothness and overall control accuracy of the entire system under multi-axis high-speed cooperative motion.

[0019] 6. The present invention centrally stores and manages complete sets of process parameters for different workpiece models through the process parameter management module, and automatically calls and distributes them after identifying the workpiece, realizing "one-click production changeover", which greatly enhances the flexible production capability of the equipment, reduces the dependence on the experience of operators, and ensures the rapid and accurate reproduction of high-quality processes. Attached Figure Description

[0020] Figure 1 is a schematic diagram of the overall structure of the present invention.

[0021] Figure 2 is an internal flowchart of the contour data processing module of the present invention.

[0022] Figure 3 is an internal control block diagram of the adaptive lifting control module of the present invention.

[0023] Figure 4 is a control flowchart of the dynamic pressure regulation module of the present invention.

[0024] Figure 5 is a flowchart of the synchronous motion synthesis module of the present invention.

[0025] Figure 6 is a flowchart of the process parameter management module of the present invention. Detailed Implementation

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

[0027] This invention provides a control system for a self-lifting contour tapered transfer machine, as shown in Figure 1, comprising the following modules:

[0028] The contour data processing module is used to receive and process contour data from the contour sensor and generate a tapered transfer trajectory that matches the surface contour of the tapered workpiece to be transferred.

[0029] Furthermore, in the above technical solution, referring to Figure 2, the contour data processing module specifically includes:

[0030] The contour sampling unit is used to control the contour sensor to perform equal-interval or equal-time sampling along the workpiece axis to obtain discrete workpiece surface contour point cloud data.

[0031] The curve fitting unit is used to smoothly fit the contour point cloud data using a cubic spline interpolation algorithm to generate a continuous workpiece generatrix equation.

[0032] The trajectory mapping unit is used to calculate and map the spatial motion path of the transfer head in the workpiece coordinate system based on the workpiece generatrix equation, the initial wrap angle of the transfer head, and the elastic deformation coefficient of the transfer material through coordinate transformation, as the tapered transfer trajectory.

[0033] It is important to know that the working principle and specific implementation details of the contour data processing module are as follows:

[0034] The contour sampling unit sends motion commands to the servo axis that drives the contour sensor via the device's bus controller (such as an EtherCAT master station). This causes the probe of the contour sensor (such as a laser displacement sensor or a contact probe) to move along the workpiece axis at a constant speed V, starting from the bottom reference surface of the conical workpiece. scan (e.g., 10 mm / s) or moves at a constant speed at a preset fixed interval ΔL (e.g., 0.5 mm). During the movement, the contour sampling unit moves at a fixed sampling frequency f. s (e.g., 1 kHz) Real-time reading of the measurement value d from the contour sensor i (i.e., the distance from the probe to the workpiece surface) and the corresponding axial position zi Simultaneously, the system synchronously reads the angle signal θ from the rotary spindle encoder. i . (z) i d i The data pairs are associated with their corresponding circumferential angles to form a discrete workpiece surface contour point cloud dataset P. cloud ={(z) i r i θ i )}, where r i To install a reference distance and d via a sensor i The calculated radial coordinates of the workpiece surface.

[0035] The curve fitting unit first processes the acquired raw point cloud data P cloud Preprocessing includes: removing abnormal noise caused by surface impurities or vibrations using sliding window mean filtering or median filtering algorithms; then, for a specific circumferential cross-section of the workpiece (i.e., the same θ value), extracting all its (z... i r i The data points form a two-dimensional point set P that describes the shape of the generatrix of the workpiece at that angle. 2D .

[0036] Next, the cubic spline interpolation algorithm is used to perform P... 2D To perform a smooth fit and generate a continuous workpiece generatrix equation, the specific steps are as follows:

[0037] A1, P 2D The points in the array are arranged in ascending order of their z-coordinates;

[0038] A2. Construct a cubic spline function S(z) passing through all data points, with z as the independent variable and r as the dependent variable. This function is valid in each subinterval [z...]. j , z {j+1} The expression is a cubic polynomial and satisfies that S(z), S'(z) (first derivative, representing slope) and S''(z) (second derivative, representing curvature) are continuous throughout the entire domain.

[0039] A3. To obtain a smooth profile that conforms to physical meaning, the boundary conditions are usually set as "natural boundary conditions", that is, S''(z0) = S''(z0). n =0 indicates that the curvature is zero at the start and end points of the workpiece contour.

[0040] Through the above fitting, a generatrix equation r=S(z) that can accurately characterize the outer contour of the workpiece is obtained.

[0041] The trajectory mapping unit calculates the spatial motion path of the transfer head based on the fitted workpiece generatrix equation r=S(z) and the transfer process requirements. The specific mapping process is as follows:

[0042] B1. Define the coordinate system: Establish the workpiece coordinate system O w -X w Y w Z w Z w The shaft coincides with the workpiece axis, X w The axis points in a certain radial direction. Establish the transfer head tool coordinate system O. t -X t Y t Z t ;

[0043] B2. Calculation of Desired Contact Point: Let the ideal wrap angle (initial wrap angle) of the transfer head (such as a rubber roller) be α (e.g., 30°). For a point (z, S(z)) on the workpiece generatrix, the desired center O of the transfer head is... t Coordinates (X) in the workpiece coordinate system t，w Z t，w It should satisfy the following: the cylindrical surface of the transfer head is tangent to the point, and the normal direction at the contact point is perpendicular to the X-axis. w The included angle between the axes is half the containment angle α (for symmetrical transfer), and X can be calculated using geometric relationships. t，w =S(z)+R t / cos(α / 2), where R t Z is the radius of the transfer head. t，w =z (assuming no axial tilt);

[0044] B3. Elastic Deformation Compensation: Considering the elastic deformation coefficient k of the transfer material (such as the silicone layer). e The actual injection amount δ is related to the theoretical pressure F. To ensure accurate trajectory, reverse compensation is required for the center position of the transfer head; the compensation amount Δ c It can be calculated based on material mechanics models (such as simplified formulas of the Hertzian contact model) or through experimentally calibrated F-δ curves, for example, Δ c =k e ×F nom , where F nom Set a nominal pressure at that point and adjust the compensation amount Δ. c Superimposed on X along the normal direction of the contact point tw On the coordinate system, the compensated center coordinates X of the transfer head are obtained. tw '=X tw +Δ c ;

[0045] B4. Trajectory Sequence Generation: Along the Zw axis, with a step size of axial feed resolution ΔZ (e.g., 0.1 mm) required by the transfer process, traverse the generatrix equation S(z), repeating steps b and c, to calculate a series of discrete transfer head tool center point positions (X). t，w，i ', Zt，w，i ), forming a discrete set of spatial motion path points;

[0046] B5. Path Smoothing and Speed ​​Planning: For the discrete path point set mentioned above, spline interpolation is used again to generate a smooth spatial curve T(t), which serves as the final tapered transfer trajectory. Simultaneously, based on the required transfer linear speed V... print The space curve is parameterized such that the feed rate corresponding to the point T(t) on the trajectory satisfies ||dT / dt||≈V print .

[0047] An adaptive lifting control module, connected to the contour data processing module and the lifting mechanism drive unit, is used to calculate and generate real-time position commands for the lifting motor based on the tapered transfer trajectory, so as to drive the transfer head to synchronously track the workpiece taper in the vertical direction.

[0048] Furthermore, in the above technical solution, referring to Figure 3, the adaptive lifting control module specifically includes:

[0049] The trajectory differentiation unit is used to perform first-order differentiation on the vertical component of the tapered transfer trajectory to obtain the real-time tracking speed feedforward signal of the transfer head in the vertical direction.

[0050] The position closed-loop unit is used to receive the real-time tracking speed feedforward signal and compare it with the actual position fed back by the lifting motor encoder, and calculate the position error correction amount through the position loop PID controller.

[0051] The instruction synthesis unit is used to add the real-time tracking speed feedforward signal and the position error correction amount to synthesize the real-time position command of the lifting motor, so that the lifting motion of the transfer head can accurately track the rotation and contour changes of the workpiece.

[0052] It is important to know that the adaptive lifting control module is a real-time motion controller based on a "feedforward-feedback" composite control strategy, and its specific implementation process is as follows:

[0053] The adaptive lifting control module takes the tapered transfer trajectory T(t) from the contour data processing module as input. This trajectory has been parameterized, and its vertical (Z-axis) component Z... des (t) represents the target position that the lifting motor needs to track. The core task of the module is to generate the real-time position command Cmd for driving the lifting motor (usually a servo motor or linear motor) in a high-bandwidth, low-latency manner. pos (t), making the actual vertical position Z of the transfer head act (t) Precisely follow Z des (t).

[0054] The trajectory differential unit in each control cycle T c (For example, within 1 ms) the desired trajectory Z des (t) Perform first-order numerical differentiation to calculate the desired velocity V of the transfer head in the vertical direction. ff (t), serving as the velocity feedforward signal. The specific calculation can be performed using the backward difference method:

[0055] V ff (k) = [Z des (k)-Z des [(k-1)] / T c ,

[0056] Where k represents the kth control cycle.

[0057] To suppress high-frequency noise in the differential caused by trajectory discretization or other noise, the calculated V can be... ff (k) Perform low-pass filtering, with the cutoff frequency set according to the system's mechanical bandwidth (e.g., 50Hz). This velocity feedforward signal V ff (t) directly reflects the expected motion trend and is used to compensate for the inertia of the system in advance, reducing tracking lag.

[0058] The position closed-loop unit constitutes the negative feedback loop of the system, and its input is the feedforward signal V. ff (t) and the actual position Z from the encoder feedback of the lifting motor act (t), This unit internally maintains a digital position loop PID controller, and the specific steps are as follows:

[0059] C1. Position Error Calculation: In each control cycle, calculate the deviation E between the desired position and the actual position. pos (k) = Z des (k)-Z act (k).

[0060] C2, PID control calculation: Position loop PID controller for E pos (k) performs the calculation. Its discretized incremental PID algorithm can be expressed as:

[0061] ΔU pos (k) = Kp pos ×[E pos (k)-E pos [(k-1)]+Ki pos ×E pos (k)×T c +Kd pos ×[E pos (k)-2×E pos (k-1)+E pos [(k-2)] / T c ,

[0062] Among them, Kp pos Ki pos Kd pos These are the proportional, integral, and differential gain coefficients of the position loop, which need to be tuned according to the mechanical characteristics of the lifting mechanism (such as inertia, stiffness, and damping). The integral term is used to eliminate steady-state error, while the differential term is used to predict the error change trend and enhance system damping.

[0063] C3, Error Correction Output: Outputs the PID calculation result U... pos (k) (or increment ΔU) pos (k) The accumulated result is used as the position error correction amount V. fb (t), this correction amount is essentially a speed command used to correct position tracking deviations caused by factors such as friction, load disturbance, and model inaccuracy.

[0064] The instruction synthesis unit is responsible for fusing feedforward and feedback signals to generate the final motor instruction.

[0065] C4. Command Synthesis: The velocity feedforward signal V output by the trajectory differential unit is... ff (t) and the velocity feedback correction V output by the position closed-loop unit fb (t) are directly added together to synthesize the speed command V of the lifting motor. cmd (t) = V ff (t) + V fb (t).

[0066] C5. Position Command Generation and Issuance: In digital control systems, position commands are typically sent to the servo drive. Therefore, the synthesized speed command V needs to be generated and issued. cmd (t) is integrated to obtain the position command Cmd. pos (t):

[0067] Cmd pos (k) = Cmd pos (k-1)+V cmd (k)×T c ,

[0068] Finally, Cmd pos (k) The position command is synchronously transmitted in digital form to the lifting mechanism drive unit (servo drive) via a real-time communication bus (such as EtherCAT or PROFINETIRT). After receiving this position command, the servo drive runs a higher frequency current loop and speed loop internally, driving the motor to precisely reach the specified position.

[0069] It is also important to know that before the transfer begins, the system needs to perform a zero-return operation to establish an accurate mechanical zero point. When the transfer starts, the timing of the instructions from the adaptive lifting control module must be strictly synchronized with the workpiece's rotation angle (via the spindle encoder signal) and the interpolation cycle of the synchronous motion synthesis module.

[0070] To improve adaptability to trajectory segments with different slopes (taperes), the position loop PID parameters can be designed to vary with the trajectory slope dZ. des / dt (i.e., the desired velocity magnitude) changes. For example, appropriately increasing the proportional gain Kp in the steep slope section (rapid ascent and descent). pos To accelerate the response, the gain is appropriately reduced in the low-slope range (gradual rise and fall) to improve stability.

[0071] The instruction synthesis unit needs to process the final synthesized speed instruction V. cmd (t) and the position command Cmd pos (t) Perform amplitude limiting to ensure that it does not exceed the maximum speed, acceleration and stroke limits allowed by the motor and mechanical structure.

[0072] The dynamic pressure adjustment module, connected to the pressure sensor and the pressure execution unit, is used to perform PID calculations based on the theoretical pressure values ​​at each point on the tapered transfer trajectory and the real-time pressure values ​​fed back by the pressure sensor, to generate dynamic pressure compensation commands to maintain the transfer pressure constant at different diameters of the tapered workpiece.

[0073] Furthermore, in the above technical solution, referring to Figure 4, the dynamic pressure regulation module specifically includes:

[0074] The pressure planning unit is used to query a preset pressure-curvature relationship table based on the radius of curvature of the current point on the tapered transfer trajectory and the transfer process parameters, and output the theoretical pressure value of that point.

[0075] The deviation calculation unit is used to calculate the pressure deviation between the theoretical pressure value and the real-time pressure value fed back by the pressure sensor in real time.

[0076] An online compensation unit is used to input the pressure deviation to a PID controller with anti-integral saturation function. The PID controller outputs the pressure compensation command to an electro-hydraulic proportional valve or a servo electric cylinder to dynamically adjust the clamping force of the transfer head on the workpiece surface.

[0077] It should be noted that the dynamic pressure regulation module is a real-time pressure closed-loop control system, and its specific implementation details are as follows:

[0078] Overall control objectives and architecture:

[0079] The core objective of this module is to ensure the clamping force F of the transfer head on the surface of the conical workpiece.actual Throughout the entire transfer process (i.e., along contours of different diameters), the pressure remains consistent with the theoretical pressure value Ftarget planned by the system to offset pressure fluctuations caused by factors such as changes in workpiece curvature and transfer head deformation. This module uses the feedback signal P from a pressure sensor (such as a strain gauge sensor or a piezoelectric sensor). fbk and F from the pressure planning unit target As input, after closed-loop calculation, the output pressure compensation command Cmd is generated. press Provide current commands to pressure actuators, such as electro-hydraulic proportional valves or position / force commands to servo electric cylinders.

[0080] The pressure planning unit determines F in real time based on the geometric and process properties of the current transfer point on the tapered transfer trajectory. target The specific steps are as follows:

[0081] D1. Calculation of Radius of Curvature: For the current point on the trajectory, its radius of curvature ρ can be directly calculated based on the workpiece generatrix equation r=S(z) generated by the contour data processing module. For the function y=S(z), the formula for the radius of curvature at point z is:

[0082] ρ(z)=[1+(S'(z))^2]^(3 / 2) / |S''(z)|,

[0083] Here, S'(z) and S''(z) are the first and second derivatives of the generatrix equation, respectively, which have been obtained during trajectory generation or can be calculated in real time.

[0084] D2. Query the pressure-curvature relationship table: The system has a pre-stored pressure-curvature relationship table. Press (ρ). This unit, based on the calculated ρ(z), in Table Press You can perform a search within the specified range. The search methods can be:

[0085] Directly look up the table: If ρ is the same as a certain standard radius of curvature ρ in the table... i If they are equal, the corresponding theoretical pressure value F will be output directly. table (ρ) i ).

[0086] Linear interpolation: More commonly, ρ lies between two adjacent ρ values ​​in the table. i and ρ {i+1} Linear interpolation is used to calculate the values ​​between them.

[0087] F target =F table (ρ) i )+[(F table (ρ) {i+1} )-F table (ρ) i )) / (ρ{i+1} -ρi)]×(ρ-ρ i ),

[0088] D3. Process Parameter Correction: The obtained baseline pressure value needs to be adjusted based on the material type parameter and baseline pressure parameter F issued by the process parameter management module. base Scaling or offset corrections can be made. For example, a material coefficient K can be introduced for transfer materials with different hardnesses. mat The final theoretical pressure value F target =K mat ×F base ×F table (ρ); The material coefficient Kmat is a dimensionless correction factor used to quantify the influence of the physical properties of different transfer materials (such as silicone, polyurethane, rubber, etc.) such as hardness and elastic modulus on the required transfer pressure. Its calibration method is as follows:

[0089] Select a standard transfer material (such as medium-hardness silicone) and define its corresponding Kmat reference value as 1.0; under the same workpiece curvature radius, wrap angle, linear velocity, and other process conditions, conduct transfer tests using the material to be calibrated and the standard material respectively; dynamically adjust the transfer pressure until the two materials achieve the same target transfer effect at the same position, such as the same ink layer transfer rate or pattern clarity; record the stable pressure value F required for the material to be calibrated to achieve the same effect. material The required stable pressure value F for standard materials standard The material coefficient is calculated using the following formula:

[0090] K mat =F material / F standard ,

[0091] Preferred range: Based on experimental data of common transfer materials, the material coefficient K mat Typical values ​​range from 0.5 to 2.0. More preferably, for most general-purpose elastomer transfer materials, K... mat The value ranges from 0.8 to 1.5. For example:

[0092] For materials with high hardness and small deformation (such as certain engineering polyurethanes), K mat It could be between 0.8 and 1.0;

[0093] For materials with lower hardness and greater flexibility (such as specialty silicone), K mat It could be 1.2-1.5.

[0094] The deviation calculation unit acquires the actual pressure signal and calculates the deviation. The specific steps are as follows:

[0095] E1. Signal Acquisition and Processing: The unit uses an analog input module (such as the AI ​​module of a PLC) or a direct digital interface to input signals at a fixed sampling period T. p (For example, 1ms) Read the voltage or current signal V from the pressure sensor. fbk By using the preset calibration coefficient K sensor (Unit: N / V or N / mA) Convert this to a real-time physical pressure value F. fbk =K sensor ×V fbk To suppress measurement noise, F can be adjusted. fbk Perform a first-order low-pass filter.

[0096] E2. Deviation Calculation: Calculate the pressure deviation E in each control cycle. press (k) = F target (k)-F fbk (k).

[0097] The online compensation unit is the core of the pressure closed loop, employing a digital PID controller with anti-windup functionality. The specific steps are as follows:

[0098] F1, PID control algorithm: The controller responds to pressure deviation E press (k) is used for calculation. A positional PID algorithm is employed:

[0099] U press (k) = Kp p ×E press (k) + Kip × Σ (E) press (j))+Kd p ×[E press (k)-E press [(k-1)] / T p ,

[0100] Among them, Kp p Ki p Kd p These are the PID parameters for the pressure loop. Σ(E) press (j) is the sum of errors (integral term).

[0101] F2. Anti-integral saturation treatment: To prevent system malfunction due to the continuous accumulation of the integral term caused by actuator saturation (such as when the valve is fully open or the cylinder has reached the end of its stroke), an anti-integral saturation mechanism needs to be introduced. A common method is: when the control output U... press (k) Exceeding the physical limits of the actuator [U] min U max When ], freeze the accumulation of integral terms, or correct the integral terms in reverse according to the degree of saturation;

[0102] The parameter Umin and U max These represent the lowest and highest effective control commands of the pressure actuator, respectively. Their specific physical meanings and values ​​depend on the type of pressure actuator used.

[0103] When the pressure actuator is an electro-hydraulic proportional valve:

[0104] U min The starting operating current of a proportional valve is typically 4mA or 0V (voltage type). Below this value, the valve cannot reliably open or respond.

[0105] U max The rated maximum operating current of the proportional valve is typically 20mA or 10V, corresponding to the maximum valve opening.

[0106] Therefore, for an electro-hydraulic proportional valve controlled by 4-20mA, U min and U max They are usually set to 4 and 20 respectively.

[0107] When the pressure actuator is a servo electric cylinder (operating in force control mode):

[0108] U min and U max These represent the minimum and maximum allowable values ​​of the servo drive force command, respectively, and their units are usually Newtons (N) or percentages (%).

[0109] Its value is set based on the rated thrust and safety margin of the servo electric cylinder. For example, if the rated thrust of the electric cylinder is 1000N, and it is a protective mechanism, U can be set. max 800N (80% of rated value), U min It is 0N or a very small preload value (such as 10N).

[0110] When the pressure actuator is a servo electric cylinder (operating in position control mode to fine-tune the pressure):

[0111] U min and U max These represent the lower and upper limits of the radial position offset that the transfer head is allowed to have in order to compensate for pressure, usually in millimeters (mm).

[0112] Its value is determined based on the maximum allowable compression of the transfer material and the mechanical structure clearance; for example, U can be set. min =-0.5mm (allowed retraction), U max =+2.0mm (press-in is allowed).

[0113] F3, Output Pressure Compensation Command: This command adjusts the output pressure of the PID controller. press (k) Limiting the amplitude in [Umin U max Following this, Cmd serves as the final pressure compensation command. press (k). The instruction was sent to:

[0114] Electro-hydraulic proportional valve: Cmd press Typically, it is an analog current signal (such as 4-20mA), the magnitude of which is proportional to the valve opening, thereby adjusting the output force of the hydraulic cylinder.

[0115] Servo electric cylinder: Cmd press This could be an additional force command (in force control mode) or a position offset command for fine-tuning (in position control mode) to achieve precise pressure adjustment.

[0116] Furthermore, in the above technical solution, the pressure-curvature relationship table is established in the following way:

[0117] During the pre-calibration stage, the control system drives the transfer head to contact a set of standard samples with different radii of curvature at a constant pressure.

[0118] Adjust the pressure of the transfer head on the standard sample until the same transfer effect is achieved, and record the actual feedback value of the pressure sensor at this time;

[0119] The radius of curvature is fitted with the corresponding actual feedback value using a polynomial to generate a continuous relationship curve for online query, and stored as the pressure-curvature relationship table.

[0120] It should be noted that the specific implementation steps of the pressure-curvature relationship table are as follows:

[0121] G1. Prepare a set of known and precisely different radii of curvature ρ1, ρ2, ..., ρ... m Cylindrical or conical standard samples, covering the possible curvature range of the workpiece to be transferred.

[0122] G2, For each standard sample ρ i The control system does not apply constant pressure; instead, it dynamically adjusts the pressure of the transfer head on the standard sample. Specifically, while keeping other process parameters (such as linear speed and ink volume) constant, the control pressure actuator changes the pressure of the transfer head on the sample, while monitoring the transfer effect (e.g., detecting the integrity of the transfer pattern, ink layer thickness, or edge sharpness through an online vision system).

[0123] G3. When the monitored transfer effect reaches the preset "same transfer effect" standard (such as the same, qualified pattern quality), the control system immediately locks the current adjustment state and records the stable pressure value fed back by the pressure sensor at this time as the radius of curvature ρ. iThe corresponding Fmeasured(ρi).

[0124] G4. Obtain the complete set of data pairs {(ρ)} i F measured (ρ) i After that, the least squares method is used to fit the polynomial, for example, a quadratic polynomial: F model (ρ) = a×ρ^2 + b×ρ + c, the goal of the fitting is to make the calculated value F of the model... model (ρ) i ) and measured value F measured (ρ) i The overall error between ) is the smallest; 'a' is the quadratic coefficient, representing the acceleration or curvature of pressure as the radius of curvature changes. When a>0, it indicates that the pressure-curvature relationship curve opens upward; when a<0, it opens downward. Its absolute value reflects the sensitivity of pressure to higher-order changes in curvature; B is the linear coefficient, representing the linear trend or slope of pressure as the radius of curvature changes, and is the main regulating term in the relationship; C is the constant term, representing the pressure base value or offset when the radius of curvature approaches zero (theoretically infinite curvature, such as a sharp edge); these are discrete data obtained from the pre-calibration experiment for {(ρ i F measured (ρ) i The mathematical results are automatically calculated after performing least squares regression analysis.

[0125] G5. The continuous function F obtained from the fitting is... model (ρ) Discretization: Generate a lookup table (Table) at intervals of a certain radius of curvature (e.g., Δρ = 1 mm). Press (ρ), stored in the system's non-volatile memory (such as EEPROM or flash memory). This table establishes the theoretical pressure settings required to obtain consistent transfer quality on workpieces with different curvatures.

[0126] The synchronous motion synthesis module is communicatively connected to the contour data processing module, the adaptive lifting control module, and the dynamic pressure adjustment module, respectively. It is used to perform spatiotemporal synchronous coupling of the tapered transfer trajectory, real-time position command, and pressure compensation command to generate the final multi-axis cooperative motion control command, and send it to the lifting mechanism drive unit and the pressure execution unit.

[0127] Furthermore, in the above technical solution, referring to Figure 5, the synchronous motion synthesis module specifically performs the following steps:

[0128] Receive the tapered transfer trajectory sequence from the contour data processing module and divide it into several interpolation periods according to time slices;

[0129] At the beginning of each interpolation cycle, the current real-time position command output by the adaptive lifting control module and the current pressure compensation command output by the dynamic pressure adjustment module are read.

[0130] The kinematic model is invoked to decouple and normalize the trajectory points, position commands, and pressure commands within the same interpolation cycle, generating a coordinated motion control command data package containing the target position of the lifting axis and the target value of the pressure axis.

[0131] At the end of the interpolation cycle, the coordinated motion control command data packet is synchronously sent to the corresponding drive unit via the real-time bus.

[0132] It is important to know that the synchronous motion synthesis module is the "command center" of multi-axis motion control, responsible for ensuring strict synchronization among spatial trajectory tracking, lifting and lowering, and constant pressure control. Its specific implementation process and key details are as follows:

[0133] This module operates within a fixed interpolation period T. interp (For example, 2ms). This period is typically an integer multiple of the slowest control loop period of the entire system, and is synchronized with the synchronization period T of the real-time communication bus (such as EtherCAT). sync Alignment or integer multiples thereof. The tapered transfer trajectory T(t) received by this module from the contour data processing module is essentially a high-density spatial point sequence {P}. i = (X i Z i )} and its corresponding expected timestamp t i The core task of the synchronous motion synthesis module is to synthesize this macroscopic trajectory with the microscopic adjustment quantities output by the two real-time control modules (adaptive lifting control module and dynamic pressure regulation module) at a unified T. interp Integration and replanning are carried out under the time grid.

[0134] H1. Trajectory reception and period division:

[0135] The synchronous motion synthesis module receives a complete trajectory sequence from the contour data processing module. This sequence has been time-parameterized according to the process line velocity, i.e., each trajectory point P... i Associate an absolute time t calculated from the start of the transfer. i The synchronous motion synthesis module internally maintains an interpolation counter N and a current interpolation cycle start time T. current .

[0136] The partitioning process is as follows: starting from t=0, with T interp The continuous trajectory time axis is divided into a series of time windows [T] at intervals. current T current +T interpFor the Nth interpolation cycle, its corresponding trajectory segment contains all segments that satisfy T. current ≤t i <T current +T interp The trajectory point {P k Simultaneously, the module calculates and stores the starting point P of the trajectory within this cycle. start End point Pend, and based on P start and P end The calculated average velocity vector is used for subsequent look-ahead processing.

[0137] H2. Synchronous reading of multi-source instructions:

[0138] In each interpolation cycle T interp At the start time (a precise hardware interrupt or bus synchronization event), the module performs a synchronous read operation:

[0139] Read lifting command: Read the real-time position command Cmd calculated by the adaptive lifting control module in this cycle via shared memory or internal communication interface. pos This instruction is for the lifting motor to resume operation in the next control cycle (usually longer than T). interp The target position (shorter) is determined by this module based on the vertical component Z of the trajectory. des It is calculated in advance by the feedforward-feedback algorithm.

[0140] Read the pressure command: In the same way, read the current pressure compensation command Cmd output by the dynamic pressure regulation module. press This instruction is the adjustment amount (such as milliampere current or micrometer position) required by the pressure actuator (electrohydraulic proportional valve or servo electric cylinder) to maintain constant pressure.

[0141] H3. Instruction fusion based on kinematic models:

[0142] The kinematic model is defined as follows:

[0143] Coordinate system and variable definition:

[0144] Workpiece coordinate system {W}: O w -X w Y w Z w Z w The shaft coincides with the workpiece axis.

[0145] Transfer head coordinate system {T}: O t -X t Y t Z t , origin O t Located at the geometric center of the transfer head.

[0146] Key parameter: Transfer head radius R t The process setting is the wrap angle α, and the elastic deformation coefficient k of the transfer material is... e The theoretical pressure value F at the current point target .

[0147] Core mathematical model formula:

[0148] Given the workpiece generatrix equation r=S(z) generated by the contouring data processing module, for the axial position z, to ensure the transfer head contacts with an angle α and compensates for elastic deformation to maintain pressure F target Transfer head center O t The theoretical target position (X) in the workpiece coordinate system {W} t，target Z t，target The following model is used to determine:

[0149] X t，target =S(z)+R t / cos(α / 2)+k e ×F target ,

[0150] Z t，target =z,

[0151] Where S(z)+R t / cos(α / 2) represents the center position of the transfer head that satisfies the geometric contact condition (the cylindrical surface of the transfer head is tangent to the conical surface of the workpiece at a specified wrap angle); k e ×F target Based on the elastic deformation coefficient k e and theoretical pressure F target The calculated radial position compensation is used to compensate for the deformation of the transfer head material caused by the applied pressure. This is the key feedforward term for achieving constant pressure control; z is the axial position that the transfer head needs to track.

[0152] The process of calling and solving the model in the synchronous motion synthesis module:

[0153] Model input: The input includes the trajectory point information (z, S(z)) corresponding to the current interpolation cycle and the theoretical pressure value F of the current point from the dynamic pressure adjustment module. target Real-time position command Cmd from the lifting axis of the adaptive lifting control module pos (corresponding to Z) t，target (tracking value), and pressure closed-loop compensation command Cmd from the dynamic pressure regulation module. press (The output of the pressure PID controller serves as the basis for F) target The fine-tuning amount ΔF), in addition to the fixed parameter R. t , α, k e .

[0154] Axis command resolution:

[0155] The final command for the Z-axis (lift axis) is Z. final The model will receive Cmd pos With model calculated value Z t，target Verification is performed. Typically, a smoothed and filtered Cmd (e.g., S-curve velocity planning) is used directly. pos As the final instruction, namely Z final =smooth filter（ Cmd pos ).

[0156] The final instruction for the pressure regulating axis: The model, based on the type of pressure actuator, sets the pressure control target (F)... target +ΔF) is converted to the corresponding axis command.

[0157] For servo electric cylinders (position control mode): the total pressure target needs to be converted into an additional radial position offset. Based on the model, the pressure axis target position command X... p，final for:

[0158] X p，final =S(z)+R t / cos(α / 2)+k e ×(F target +ΔF),

[0159] Wherein, ΔF is Cmd press This command directly drives the transfer head to the compensated target position.

[0160] For electro-hydraulic proportional valves (force control mode): Target force command F on the pressure axis p，final for:

[0161] F p，final =F target +ΔF,

[0162] The model is then tested using the valve's force-current static characteristic curve I. valve =g(F), which is converted into the control current value I. valve，cmd =g(F p，final ).

[0163] Spatiotemporal synchronization and normalization: the calculated Z final and X p final (or I valve (cmd) Normalized to the end time T of this interpolation cycle current +T interp This means that the instruction data packet explicitly requires each execution axis to reach the instruction target value at that precise moment, thereby achieving hard synchronization of multi-axis motion and eliminating timing errors.

[0164] H4. Command data packet generation and synchronous distribution:

[0165] Packet encapsulation: Encapsulating the processed Z... final The pressure axis command value, along with necessary control words (such as mode selection and enable signals) and cycle counter N, are packaged into a structured cooperative motion control command data package.

[0166] Bus synchronous transmission: during interpolation period T interp Within a fixed time window before the end (e.g., the last 100μs), the module sends out data packets via the synchronization management mechanism of a real-time industrial Ethernet bus (e.g., EtherCAT). The EtherCAT master station ensures that this data packet is simultaneously delivered to the mapped addresses of the lifting mechanism drive unit (servo drive) and the pressure actuator unit (valve controller or servo drive) when the next precise synchronization signal (SYNC0) arrives. All slave devices synchronously execute newly received instructions under the trigger of the same SYNC signal, thereby achieving true multi-axis hard synchronization.

[0167] The process parameter management module is communicatively connected to the contour data processing module and the dynamic pressure adjustment module, and is used to store and manage the transfer process parameter sets corresponding to different workpiece models.

[0168] Furthermore, in the above technical solution, referring to Figure 6, the process parameter management module specifically performs the following:

[0169] Once the system identifies the workpiece model, it retrieves the corresponding set of transfer process parameters from the database.

[0170] The wrap angle parameters and linear velocity parameters in the transfer process parameter set are sent to the contour data processing module to participate in the generation of the tapered transfer trajectory.

[0171] The reference pressure parameters and material type parameters in the transfer process parameter set are sent to the dynamic pressure adjustment module to participate in the calculation of the theoretical pressure value.

[0172] It's important to understand that the process parameter management module is the core of achieving "one-click production" and flexible manufacturing. It is responsible for binding and distributing the processing knowledge (process parameters) of a specific workpiece with real-time control logic. Its specific implementation details and workflow are as follows:

[0173] Module architecture and data storage:

[0174] This module can be deployed in a human-machine interface (HMI) system on an industrial computer, embedded host computer, or PLC. On the software side, it includes a process parameter database and a parameter scheduling engine. The database uses a relational database (such as SQLite) or structured files (such as XML or JSON format) for storage. For each workpiece model (e.g., "Workpiece A-Rev2.1"), a separate record is created in the database, and each record contains a structured set of transfer process parameters. This parameter set is a data collection, and its core fields typically include:

[0175] Geometric parameters: such as wrap angle α (unit: degrees), transfer linear velocity Vprint (unit: mm / s), axial feed resolution ΔZ (unit: mm);

[0176] Pressure parameters: such as reference pressure Fbase (unit: N), material elastic modulus k e Material type identification code (used to index different pressure-curvature relationship tables or correction factor K) mat );

[0177] Contouring parameters: such as contouring scanning speed V scan Sampling interval ΔL;

[0178] Quality control parameters: such as target ink layer thickness, allowable pressure fluctuation range, etc.

[0179] Version and permission information: such as parameter set version number, creator, and last modified time.

[0180] S1. Workpiece model identification and parameter set retrieval:

[0181] After the system starts, the process parameter management module is in standby mode, waiting for the workpiece model identification signal. The identification methods include, but are not limited to:

[0182] Manual selection: The operator manually selects the workpiece model to be processed from a pre-loaded list of workpiece models via the HMI touchscreen.

[0183] Automatic identification: By scanning the identification code on the workpiece or tooling with a barcode / RFID reader connected to the control system, the workpiece model information can be automatically obtained.

[0184] Image recognition: The machine vision system takes pictures of the workpiece and automatically identifies the model after comparing them with the template library.

[0185] Once valid workpiece model information is obtained (e.g., the string "PartNo12345"), the parameter scheduling engine performs a database query operation: SELECT × FROM ProcessParameterTable WHERE PartID='PartNo12345'. After a successful query, the corresponding complete set of transfer process parameters is loaded into the control system's memory workspace, such as the global variable area or shared data block.

[0186] S2. Parameter distribution and module initialization:

[0187] After the parameter set is loaded, the module does not distribute it all at once, but rather precisely according to the needs and initialization sequence of each downstream module:

[0188] Distribute to the contour data processing module: Include the wrap angle α and transfer linear velocity V from the parameter set. print Axial feed resolution ΔZ, contour scanning speed V scan Parameters such as the sampling interval ΔL are sent to the contour data processing module via internal communication interfaces (such as OPCUA, TCP / IP sockets, or global variables). These parameters will be directly used in the S3 step of tapered transfer trajectory mapping generation for the calculation of the desired contact point, trajectory sequence generation, and velocity planning (see steps B2, B4, and B5 of the contour data processing module mentioned above).

[0189] Distribute to the dynamic pressure regulation module: Distribute the reference pressure F from the parameter set base The material type identifier is sent to the dynamic pressure regulation module. The material type identifier is used to index or calculate the corresponding material coefficient K within the dynamic pressure regulation module. mat These two parameters will be directly used in the process parameter correction calculation in the S1: theoretical pressure value planning step (see step D3 of the aforementioned dynamic pressure regulation module), i.e., F target =K mat ×F base ×F table (ρ).

[0190] Distribute to the synchronous motion synthesis module: Send parameters related to motion planning, such as the maximum speed and acceleration limit values ​​of each axis, to the synchronous motion synthesis module for safety limiting and smoothing processing when generating instructions.

[0191] S3. Parameter Verification and Process Startup:

[0192] After parameter distribution is complete, the process parameter management module can perform a parameter verification, such as checking whether the required parameters are complete and whether the values ​​are within a reasonable range (e.g., pressure values ​​are not negative). Upon successful verification, the module sends a "parameter ready" signal to the system's main controller. Based on this, the main controller can sequentially initiate contour scanning, trajectory calculation, and finally, the transfer process. Throughout the transfer process, these parameters are locked as a "recipe" unless there are process changes or an anomaly occurs.

[0193] In addition to basic distribution functions, this module typically integrates the following management functions to meet actual production needs:

[0194] Parameter editing and saving: Authorized engineers can modify and optimize the parameter set of existing workpiece models through a password-protected interface and save it as a new version.

[0195] New workpiece process creation: Create a completely new set of process parameters for new workpiece models through "learning mode" or manual input, and store them in the database.

[0196] Parameter backup and recovery: Supports exporting and backing up the entire process parameter database, or restoring from the backup file to prevent data loss.

[0197] In one specific embodiment, the following table illustrates the process from contour scanning to the end of the transfer:

[0198] Timestamp (ms) contouring data processing module, adaptive lifting control module, dynamic pressure adjustment module, synchronous motion synthesis module, process parameter management module. t0 (start) Start contouring scan, sampling interval ΔL=0.5mm, lifting motor returns to zero, encoder feedback Z. act =0.000mm pressure sensor initialization, feedback P fbk =0.0N interpolation period T interp =Start synchronous identification of workpiece model in 2ms"Part A ", call parameter set t1 (sampling) to collect point cloud data P cloud z=0.0, r=20.0, z=0.5, r=20.1, ... ——— Transmission envelope angle α=30°, V print =50mm / s to the contouring module t2 (fitting) Fitting the generatrix equation r=S(z)=20.0+0.2z-0.01z² ——— Sending reference pressure F base =100N to pressure module t3 (trajectory generation) tapered transfer trajectory T(t): Z=0.0, X=20.51, Z=0.1, X=20.53, ... trajectory differential V ff =0.0mm / s (Refer to pressure gauge: ρ=20.0mm→F) target=98.5N received trajectory sequence, divided into interpolation periods —t4 (transfer start) — feedforward Vff=0.2mm / s, feedback correction Vfb=0.01mm / s, synthesis command Cmdpos=0.21mm / sF target =98.5N, P fbk =97.8N, deviation E press =0.7N Solution: Z final =0.1mm, X p，final =20.53mm—t5 (in transfer)—Cmd pos =0.25mm / s, Z act =0.12mmρ=20.1mm→F target =98.7N, P fbk =98.5N, E press =0.2N, PID output Cmd press =4.2mA synchronous transmission: Z-axis = 0.12mm, pressure axis = 20.55mm —t6 (curvature change) —Cmd pos =0.30mm / s, Z act =0.18mmρ=20.3mm→F target =99.2N, P fbk =99.0N, E press =0.2N, Cmd press =4.5mA synchronous transmission: Z-axis = 0.18mm, pressure axis = 20.60mm —t7 (transfer end) —Cmd pos =0.0mm / s, Z act =50.0mm (workpiece length) ρ=30.0mm→F target =102.0N, P fbk =101.8N, E press =0.2N, Cmd press =5.0mA sends the end command, all axes stop saving the current process log, and record the key parameter ΔL=0.5mm of parameter set version V1.2. scan =10mm / s, α=30°, k e =0.005mm / N PID parameter: Kp pos =1.2, Ki pos =0.05, Kd pos =0.01 PID parameter: Kp p =0.8, Ki p =0.02, Kd p =0.05, pressure gauge fitting: a=-0.001, b=0.5, c=90T interp=2ms, Communication bus: EtherCAT, Synchronization period 1ms, Parameter set fields: α, V print F base k e Material type units: mm, mm / s, °, mm / N, mm / s, mmN, mA, mm, ms surface

[0199] Finally, it should be noted that the above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A control system for a self-lifting contour tapered transfer machine, characterized in that, It includes the following modules: a contour data processing module, which receives and processes contour data from the contour sensor to generate a tapered transfer trajectory that matches the surface contour of the tapered workpiece to be transferred; An adaptive lifting control module, connected to the contour data processing module and the lifting mechanism drive unit, is used to calculate and generate real-time position commands for the lifting motor based on the tapered transfer trajectory, so as to drive the transfer head to synchronously track the workpiece taper in the vertical direction. A dynamic pressure adjustment module, connected to the pressure sensor and the pressure execution unit, is used to perform PID calculations based on the theoretical pressure values ​​at each point on the tapered transfer trajectory and the real-time pressure values ​​fed back by the pressure sensor, to generate dynamic pressure compensation commands to maintain constant transfer pressure at different diameters of the tapered workpiece. A synchronous motion synthesis module, communicatively connected to the contour data processing module, the adaptive lifting control module, and the dynamic pressure adjustment module, is used to perform spatiotemporal synchronous coupling of the tapered transfer trajectory, real-time position commands, and pressure compensation commands to generate the final multi-axis cooperative motion control commands, and send them to the lifting mechanism drive unit and the pressure execution unit. A process parameter management module, communicatively connected to the contour data processing module and the dynamic pressure adjustment module, is used to store and manage the transfer process parameter sets corresponding to different workpiece models.

2. The control system of the self-lifting contour tapered transfer machine according to claim 1, characterized in that, The contour data processing module specifically includes: a contour sampling unit, used to control the contour sensor to sample at equal intervals or at equal times along the workpiece axis to obtain discrete workpiece surface contour point cloud data; a curve fitting unit, used to use a cubic spline interpolation algorithm to smoothly fit the contour point cloud data to generate a continuous workpiece generatrix equation; and a trajectory mapping unit, used to calculate and map the spatial motion path of the transfer head in the workpiece coordinate system based on the workpiece generatrix equation, the initial wrap angle of the transfer head, and the elastic deformation coefficient of the transfer material through coordinate transformation, as the tapered transfer trajectory.

3. The control system of the self-lifting contour tapered transfer machine according to claim 1, characterized in that, The adaptive lifting control module specifically includes: a trajectory differentiation unit, used to perform first-order differentiation on the vertical component of the tapered transfer trajectory to obtain a real-time tracking speed feedforward signal of the transfer head in the vertical direction; a position closed-loop unit, used to receive the real-time tracking speed feedforward signal and compare it with the actual position fed back by the encoder of the lifting motor, and calculate the position error correction amount through a position loop PID controller; and a command synthesis unit, used to add the real-time tracking speed feedforward signal and the position error correction amount to synthesize a real-time position command for the lifting motor, so that the lifting motion of the transfer head can accurately track the rotation and contour changes of the workpiece.

4. The control system of the self-lifting contour tapered transfer machine according to claim 1, characterized in that, The dynamic pressure adjustment module specifically includes: a pressure planning unit, used to query a preset pressure-curvature relationship table based on the radius of curvature of the current point on the tapered transfer trajectory and the transfer process parameters, and output the theoretical pressure value of that point; a deviation calculation unit, used to calculate the pressure deviation between the theoretical pressure value and the real-time pressure value fed back by the pressure sensor in real time; and an online compensation unit, used to input the pressure deviation to a PID controller with anti-integral saturation function, and the PID controller outputs the pressure compensation command to an electro-hydraulic proportional valve or a servo electric cylinder to dynamically adjust the clamping force of the transfer head on the workpiece surface.

5. The control system of the self-lifting contour tapered transfer machine according to claim 4, characterized in that, The pressure-curvature relationship table is established as follows: During the pre-calibration stage, the control system drives the transfer head to contact a set of standard samples with different radii of curvature at a constant pressure; the pressure of the transfer head on the standard samples is adjusted until the same transfer effect is achieved, and the actual feedback value of the pressure sensor at this time is recorded; the radius of curvature and the corresponding actual feedback value are subjected to polynomial fitting to generate a continuous relationship curve for online query, and stored as the pressure-curvature relationship table.

6. The control system of the self-lifting contour tapered transfer machine according to claim 1, characterized in that, The synchronous motion synthesis module specifically performs the following steps: receiving the conic transfer trajectory sequence from the contour data processing module and dividing it into several interpolation cycles according to time slices; at the beginning of each interpolation cycle, reading the current real-time position command output by the adaptive lifting control module and the current pressure compensation command output by the dynamic pressure adjustment module; calling the kinematic model to decouple and normalize the trajectory points, position commands, and pressure commands within the same interpolation cycle to generate a cooperative motion control command data packet containing the target position of the lifting axis and the target value of the pressure axis; at the end of the interpolation cycle, synchronously sending the cooperative motion control command data packet to the corresponding drive unit through the real-time bus.

7. The control system of the self-lifting contour tapered transfer machine according to claim 1, characterized in that, The process parameter management module specifically performs the following steps: when the system identifies the workpiece model, it retrieves the corresponding transfer process parameter set from the database; and sends the wrap angle parameter and linear velocity parameter from the transfer process parameter set to the contour data processing module to participate in the generation of the tapered transfer trajectory. The reference pressure parameters and material type parameters in the transfer process parameter set are sent to the dynamic pressure adjustment module to participate in the calculation of the theoretical pressure value.

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