Method, device and equipment for dynamically adjusting clamping force of thin-wall part and storage medium

Abstract

The invention discloses a method and device for dynamically adjusting the clamping force of a thin-wall part, equipment and a storage medium, and relates to the field of data simulation. The method comprises the following steps: determining the clamping form and size of a pneumatic clamp tool according to the size of a thin-wall part, simulating a clamping stress process through finite element simulation, and establishing a mapping model between clamping force and deformation; initial machining process parameters are set according to the size and precision requirements of the thin-wall part, and the maximum allowable clamping force under different material allowances is obtained based on the mapping model; stability qualitative analysis is conducted on the clamping stability, and milling parameters are optimized according to the analysis result; and the milling process and the milling parameters are obtained in real time, and the clamping force in the milling process is dynamically adjusted at fixed time by controlling the pneumatic clamp tool through the PLC. Dynamic adjustment of the clamping force is achieved through the established mapping model of the clamping force and deformation, and the problem of deformation caused by rigidity change of the thin-wall part in the machining process is solved by combining layered milling optimization and PLC timing control.

Description

Technical Field

[0001] The present application relates to the field of data simulation, and in particular to a method, device, equipment and storage medium for dynamically adjusting the clamping force of thin-walled parts. Background Art

[0002] Thin-walled parts, with their advantages of light weight, high specific strength, and compact structure, are widely used in aerospace, defense technology, automotive manufacturing, and other fields. However, due to their inherent thinness, thin-walled parts are weakly rigid and prone to deformation during machining. Research shows that clamping deformation is a typical type of deformation in thin-walled parts machining, accounting for approximately 20% to 60%, and clamping force is the primary factor causing this deformation.

[0003] Traditional clamping operations involve the operator using a wrench to drive a transmission screw to clamp the thin-walled part between flat-nose pliers. This usually relies on the operator's skills and experience, and is greatly influenced by subjective factors. It is impossible to provide a quantitative and appropriate clamping force, and the clamping force is always too large or too small. Too small a clamping force will lead to clamping failure, while too large a clamping force can easily cause deformation of the thin-walled part. Some scholars have studied how to accurately set the clamping force, but have not considered the important factor that the rigidity of the thin-walled part will gradually decrease as material is removed during the processing process. Maintaining the clamping force at the initial state can easily lead to increasingly severe deformation of the thin-walled part, and ultimately affect the processing quality and performance of the thin-walled part, making it difficult to ensure that the processing accuracy meets the design accuracy requirements.

[0004] This is primarily achieved through two approaches in related technologies. First, using an integrated fixture combining a torque wrench and flat-nose pliers. In today's machining industry, flat-nose pliers are crucial basic fixtures. To precisely control the clamping force, the torque wrench's force measurement and adjustment functions are integrated into the pliers' clamping system. For example, the torque wrench's transmission component is connected to the end of the pliers' screw. Through an internal gear train or coupling, rotating the screw not only clamps the workpiece but also displays the torque corresponding to the clamping force in real time. The advantage is that the clamping force corresponding to the current torque can be calculated. The operator can then adjust the torque wrench based on experience, significantly improving the protection and machining accuracy of thin-walled parts. Second, precise control and optimization of the clamping force for thin-walled parts driven by digital twins. Digital twin technology can combine the geometric characteristics of thin-walled parts and fixtures, using real-time information collected by multi-directional sensors and 3D model virtual simulation to achieve real-time interaction and bidirectional mapping between the digital model and the physical entity. By establishing a data model through virtual simulation and entity physical model, the clamping force strategy adjustment instructions generated by big data analysis and optimization algorithm are used, and real-time feedback is provided to control the physical entity of the fixture, thereby achieving the coordinated evolution of the two.

[0005] However, for solution one, although the torque value of the torque wrench can be used to convert the clamping force, there is still no reference data source for the most appropriate clamping force value, and the determination of clamping stability under this clamping force still relies on the operator's experience. Therefore, this technical solution is greatly affected by subjective factors, relies on the operator's experience, is risky, the clamping force accuracy is not high, and the final product quality is unstable. For solution two, it is necessary to set up collection points on the thin-walled parts and arrange laser rangefinders and distance sensing equipment to obtain deformation and displacement data of the thin-walled parts monitoring points. This is expensive, and there are many precision components, which places high demands on the actual on-site processing. The most important disadvantage is that this solution obtains the optimal initial clamping force through a series of complex operating processes. It does not take into account the problem that during the actual processing process, the part material is continuously removed and the rigidity of the thin-walled parts becomes weaker and weaker. That is, after a period of processing, the rigidity of the thin-walled parts is not enough to resist the initial clamping force and deformation occurs, making it difficult to guarantee the final processing quality of the thin-walled parts. Summary of the Invention

[0006] The present application provides a method, device, equipment and storage medium for dynamically adjusting the clamping force of thin-walled parts, which has the advantages of realizing dynamic adjustment of the clamping force and taking into account both processing accuracy and cost-effectiveness.

[0007] In one aspect, the present application provides a method for dynamically adjusting the clamping force of a thin-walled part, the method comprising: The clamping form and size of the pneumatic fixture are determined according to the size of the thin-walled workpiece. The clamping force process is simulated through finite element simulation to establish a mapping model between the clamping force and deformation. Initial machining process parameters are set according to the size and precision requirements of the thin-walled part, and the maximum clamping force allowed under different material allowances is obtained based on the mapping model; Conduct stability analysis on clamping stability and optimize milling parameters based on the analysis results; According to the milling process and milling parameters, the clamping force of the milling process is dynamically adjusted regularly by controlling the pneumatic clamping tooling through the PLC.

[0008] Specifically, the cylinder of the pneumatic clamp tooling is connected to the sliding clamp block through a connecting rod. The sliding clamp block 3 is slidably arranged on one side of the base, and a fixed clamp block corresponding to the sliding clamp block is arranged on the other side of the base; The PLC controls the air regulating valve to adjust the output pressure of the cylinder 1, and drives the sliding clamp 3 to approach the fixed clamp through the connecting rod to clamp the thin-walled part, or drives the sliding clamp away from the fixed clamp to release the thin-walled part.

[0009] Specifically, the finite element simulation is used to simulate the clamping force process and establish a mapping model between the clamping force and the deformation, including: A finite element model is established, wherein the base and the clamping block are set as rigid bodies, and the thin-walled member is set as an isotropic elastic body; All degrees of freedom of the base and the fixed clamp are constrained, and a load is applied to the sliding clamp; all contacts between the thin-walled member and the base, the sliding clamp, and the fixed clamp are set to surface-to-surface friction contacts; The deformation results under different material allowances and clamping forces are obtained through finite element simulation, and the mapping model is established based on the obtained results.

[0010] Specifically, the deformation results under different material allowances and clamping forces are obtained through finite element simulation, and the mapping model is established based on the obtained results, including: Import the thin-walled part model into the finite element simulation model to construct the original data set [x, y] of different clamping forces under different milling allowances; The original data set is imported into the finite element simulation model. The deformation results of different clamping forces under different material allowances are obtained through simulation. Based on a large number of deformation results, a mapping model between clamping force and deformation is established. The mapping model is as follows:

[0011] Where D represents the deformation, x represents the material allowance, and y represents the clamping force at this material allowance.

[0012] Specifically, obtaining the maximum allowable clamping force under different material allowances based on the mapping model includes: Based on the initial machining process parameters, the milling process is divided into layers to determine the milling parameters under different material allowances; According to the dimensional accuracy requirements of the thin-walled part and the value of the milling amount of each layer, the maximum bulge deformation allowed at the middle position of the thin-walled part is reversely calculated; the maximum bulge deformation is the maximum deformation within the allowable range of the thickness dimension tolerance; The maximum clamping force under the maximum bulge deformation with different material allowances is reversely solved based on the mapping model.

[0013] Specifically, the stability determination analysis of the clamping stability and the optimization of the milling parameters according to the analysis results include: Perform milling simulation based on initial milling process parameters and extract milling forces in different directions; Based on the milling force and clamping force obtained under different layer material allowances, the clamping stability is analyzed using the stability criterion formula; If the clamping of this layer is stable, the milling parameters are kept unchanged; if the stability does not meet the requirements, the milling speed and feed speed parameters are optimized to adjust the milling force to make the clamping stable; the stability criterion formula is as follows:

[0014] Among them R n is the clamping force, is the friction coefficient between the thin-walled part and the pneumatic fixture, F c To resist the milling force in this direction.

[0015] Specifically, the real-time acquisition of the milling process and milling parameters, and the timing and dynamic adjustment of the clamping force of the milling process by controlling the pneumatic clamping tooling through the PLC, include: After obtaining the milling parameters for clamping stability, simulate the material removal of different layers in computer-aided manufacturing (CAM) software and calculate the processing time required for milling different layers. By measuring the contact area between the sliding clamp and the thin-walled workpiece in the clamping environment, the air pressure required by the clamp to apply the corresponding clamping force is calculated; The PLC is timed and programmed based on the processing time of different layers and the required air pressure. After each layer is processed, the air pressure required for removing the next layer of material is automatically adjusted to control the timing and dynamic adjustment of the clamping force of the thin-walled part during the milling process.

[0016] On the other hand, the present application provides a device for dynamically adjusting the clamping force of a thin-walled part, the device comprising: The model building module is used to determine the clamping form and size of the pneumatic fixture according to the size of the thin-walled part, simulate the clamping force process through finite element simulation, and establish a mapping model between the clamping force and deformation; a calculation module, configured to set initial processing parameters according to the size and precision requirements of the thin-walled part, and obtain the maximum allowable clamping force under different material allowances based on a mapping model; Optimization module, used to perform stability analysis on clamping stability and optimize milling parameters based on the analysis results; The adjustment module is used to obtain in real time according to the milling process and milling parameters, and to control the pneumatic clamping tooling to dynamically adjust the clamping force of the milling process through PLC.

[0017] On the other hand, the present application provides a computer device, which includes a processor and a memory, wherein the memory stores at least one instruction, at least one program, a code set or an instruction set, and the at least one instruction, the at least one program, the code set or the instruction set are loaded and executed by the processor to implement the method of dynamically adjusting the clamping force of thin-walled parts described in the above aspect.

[0018] On the other hand, the present application provides a computer-readable storage medium, which stores at least one instruction, at least one program, code set or instruction set. The at least one instruction, the at least one program, the code set or instruction set is loaded and executed by a processor to implement the method of dynamically adjusting the clamping force of thin-walled parts described in the above aspect.

[0019] The technical solutions provided by the embodiments of this application offer at least the following beneficial effects: Dynamic adjustment of clamping force is achieved by establishing a mapping model between clamping force and deformation. Combined with layered milling optimization and PLC timing control, this effectively addresses the deformation problem caused by changes in the rigidity of thin-walled parts during machining. This approach offers the advantages of dynamic clamping force adjustment while balancing machining accuracy and cost-effectiveness. Furthermore, clamping force adjustment is based on PLC timing control, eliminating the need for operators to manually adjust the machine. This improves machining efficiency while reducing the risks associated with relying on operator experience to adjust clamping force, thus alleviating the burden on operators. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 This is a flow chart of a method for dynamically adjusting the clamping force of a thin-walled part provided in an embodiment of the present application; Figure 2 Shows a schematic structural diagram of a pneumatic fixture; Figure 3 A schematic diagram of establishing a mapping model between clamping force and deformation is shown; Figure 4 The algorithm flow chart of the method for dynamically adjusting the clamping force of thin-walled parts is listed; Figure 5 A flow chart showing the timing and dynamic adjustment of the clamping force during the milling process is shown; Figure 6 A schematic diagram showing a method for dynamically adjusting the clamping force of a thin-walled part; Figure 7 A structural block diagram of a device for dynamically adjusting the clamping force of a thin-walled part provided in an embodiment of the present application is shown; Figure 8 A structural block diagram of a computer device provided by an exemplary embodiment of the present application is shown. DETAILED DESCRIPTION

[0021] In order to make the objectives, technical solutions and advantages of this application clearer, the implementation methods of this application will be further described in detail below with reference to the accompanying drawings.

[0022] In this document, "plurality" refers to two or more. "And / or" describes a relationship between associated objects, indicating that three possible relationships exist. For example, "A and / or B" can mean: A exists alone, A and B exist simultaneously, or B exists alone. The character " / " generally indicates an "or" relationship between the associated objects.

[0023] In traditional clamping processes for thin-walled parts machining, operators rely on experience to set clamping force, lacking a quantitative basis. This fixed clamping force cannot adapt to the stiffness loss caused by material removal during machining, leading to increased deformation accumulation. Existing technologies lack a dynamic model for the relationship between clamping force and deformation, making it impossible to adjust clamping force in real time based on machining progress. This results in an imbalance between milling and clamping forces.

[0024] For example, when machining thin-walled titanium alloy frames in the aerospace field, the initial clamping force is set to 800N based on experience. As the number of machining layers increases, the material allowance decreases from 5mm to 1mm, and the workpiece stiffness decreases by about 70%. At this time, the contact stress generated by the fixed clamping force exceeds the yield limit of the material, resulting in a plastic deformation of 0.15mm in the middle area of ​​the workpiece. During the milling process, when the spindle speed is 6000rpm and the feed rate is 800mm / min, the Y-axis milling force reaches 200N, exceeding the friction threshold of the clamping system and causing the workpiece to shift.

[0025] If these issues are not addressed, accumulated deformation will result in workpiece dimensional deviations and surface roughness exceeding the design requirement of 1.6μm (Ra). Imbalances between milling and clamping forces can cause tool chatter, resulting in vibration marks on the machined surface. In extreme cases, workpiece release from the fixture can interrupt machining or damage the tool, raising scrap rates to over 25%. Altered residual stress distribution in thin-walled parts will impact component fatigue life, making it impossible to meet the 10^6 cycle durability requirement for aviation structural components.

[0026] This solution addresses the issues of arbitrary clamping force application, inconsistent standards, and persistently excessive initial clamping force during thin-walled part machining. By implementing a data-driven PLC-based strategy for dynamically adjusting clamping force for thin-walled parts, the goal is to quantify clamping force based on numerical simulation and dynamically adjust clamping force as material is removed during machining, thereby minimizing deformation during clamping. Dynamic clamping force adjustment is based on PLC control, eliminating the safety risks associated with manual adjustments by the operator during machining.

[0027] Figure 1 Flowchart of a method for dynamically adjusting the clamping force of a thin-walled part provided in an embodiment of the present application, comprising the following steps: S1. Determine the clamping form and size of the pneumatic fixture according to the size of the thin-walled workpiece, simulate the clamping force process through finite element simulation, and establish a mapping model between the clamping force and deformation; Thin-walled parts, such as those in the aerospace or military sectors, are the ones that require milling in this application. Fixture type and sizing are determined based on the part's geometric features. This can be achieved by acquiring point cloud data from 3D scanning of thin-walled parts and then matching it with a library of standard fixtures.

[0028] Finite element simulation of the clamping force process refers to the construction of a virtual clamping environment through computer-aided engineering software. Specifically, ANSYS or ABAQUS software can be used to establish a mechanical model including the fixture-workpiece contact. This model is used to quantify the relationship between the clamping force and the elastic deformation.

[0029] The clamping force and deformation mapping model is a mathematical relationship established based on simulation data. Specifically, polynomial regression or neural network algorithms can be used to fit the nonlinear relationship between clamping force, material allowance, and deformation. This model provides a theoretical basis for subsequent maximum clamping force calculations. Specifically, a mapping table is generated, recording the corresponding deformation of a part made of a specific material when different clamping forces are applied during the assembly process. This provides valuable data support for subsequent predictive analysis.

[0030] S2. Set the initial processing parameters according to the size and precision requirements of the thin-walled part, and obtain the maximum clamping force allowed under different material allowances based on the mapping model; Obtaining the maximum clamping force under different material allowances means determining the safety threshold by inversely solving the mapping model. Specifically, a numerical iteration method can be used to reversely infer the clamping force extreme value within a given deformation tolerance range. This step ensures that the clamping force at different stages of the processing process is always within the material rigidity tolerance range.

[0031] The initial processing parameters are determined based on material properties, pneumatic fixture information, geometric parameters, part size, processing accuracy and various indicators. The specific size of each data can be determined through database and historical experience summary.

[0032] S3. Conduct stability analysis on the clamping stability and optimize the milling parameters based on the analysis results; The deterministic analysis of clamping stability refers to verifying the dynamic equilibrium relationship between the milling force and the clamping force. Specifically, the vector analysis method can be used to calculate the difference between the component of the milling force on the friction contact surface and the anti-slip force generated by the clamping force. This analysis prevents dimensional deviations caused by workpiece displacement during machining.

[0033] Milling parameter optimization involves adjusting milling parameters to match the current clamping conditions. If the clamping is stable for this layer, the milling parameters remain unchanged. If stability is poor, the milling speed and feed rate parameters are optimized to adjust the milling force and stabilize the clamping. Specifically, a genetic algorithm can be used to optimize the spindle speed and feed rate combination while maintaining machining efficiency. This optimization achieves real-time adaptation of milling force and clamping force.

[0034] S4. Real-time acquisition based on the milling process and milling parameters, and the PLC controls the pneumatic fixture to dynamically adjust the clamping force of the milling process.

[0035] PLC-timed dynamic clamping force adjustment automatically adjusts air pressure parameters based on the machining progress. Specifically, G-code parsing technology identifies the machining layer and triggers pressure adjustments in the pneumatic actuator. This control method eliminates the impact of manual intervention lag on machining accuracy. Finally, based on the machining time and clamping force required for milling different layers, the PLC timed control of the pneumatic clamp enables dynamic adjustment of the clamping force during the machining of thin-walled parts.

[0036] In summary, the core of this solution lies in constructing a closed-loop control system that integrates a dynamic clamping force-deformation mapping model with the machining process. Finite element simulation is used to quantify the maximum safe clamping force threshold for different material allowances. Milling parameters are optimized in real time using stability criteria. Finally, PLC timing programming is used to implement an adaptive adjustment mechanism in which the clamping force decreases with material removal, effectively suppressing cumulative deformation during thin-walled part machining. The entire process forms a closed-loop clamping force adjustment system. By quantifying the clamping force through numerical simulation and dynamically adjusting it based on material removal during machining, clamping deformation during thin-walled part machining is reduced. The use of PLC control, replacing manual operation, improves the accuracy and safety of adjustment.

[0037] In some embodiments, the stable control of thin-walled parts is achieved through the cooperation of specific pneumatic fixtures. Figure 2 The schematic diagram of the structure of the pneumatic clamping tooling is shown. The clamping tooling mainly includes a cylinder 1, a connecting rod 2, a sliding clamp 3, a fixed clamp 4, a base 5, etc. The cylinder 1 is connected to the sliding clamp 3 through the connecting rod 2. The sliding clamp 3 is slidably set on one side of the base 5. A fixed clamp 4 corresponding to the sliding clamp 3 is set on the other side of the base 5. The thin-walled part to be clamped is located between the fixed clamp 4 and the sliding clamp 3. In the actual control stage of the PLC, the air regulating valve is controlled to adjust the output pressure of the cylinder 1, and the sliding clamp 3 is driven to approach the fixed clamp 4 through the connecting rod 2 to clamp the thin-walled part, or the sliding clamp 3 is driven away from the fixed clamp 4 to loosen the thin-walled part. Specifically, the connecting rod 2 pushes the sliding clamp 3 to squeeze the thin-walled part, so that the thin-walled part is clamped and the next processing is carried out. There is a boss for positioning on one side of the fixed clamp 4 to support the thin-walled part.

[0038] Exemplarily, the cylinder is configured at the side wall of the base or in a specific mounting groove, with the axis of its piston rod parallel to the base guide rail. For example, the cylinder stroke can be set to 50-150mm to accommodate workpieces of different sizes. The connecting rod is made of carbide material, one end of which is rigidly connected to the cylinder piston rod through a flange, and the other end is connected to the sliding clamp through a ball joint. This structure can compensate for assembly errors of 0.05-0.1mm. A V-shaped guide groove is provided at the bottom of the sliding clamp, and the fitting clearance with the base guide rail is controlled within 0.02mm. Its working surface can be processed into a serrated pattern to increase the friction coefficient to 0.3-0.5. The fixed clamp is fixed to the other side of the base by bolts, and its working surface maintains a parallelism error of no more than 0.01mm with the sliding clamp, and the distance between the two can be adjusted in the range of 100-300mm.

[0039] Specifically, when the cylinder intake pressure is adjusted to 0.4-0.6MPa, the piston rod pushes the connecting rod to drive the sliding clamp along the guide rail. After contacting the thin-walled workpiece, it continues to apply pressure until the preset value is reached. The pressure sensor monitors the clamping force changes in real time. When the pressure fluctuation exceeds ±5%, the control unit immediately adjusts the opening of the air regulating valve to compensate. During the machining process, the pressure value can be adjusted in stages according to the amount of material removed. For example, 0.5MPa pressure is used in the rough machining stage and reduced to 0.3MPa in the fine machining stage. When the clamping force is released, the cylinder exhaust valve opens to reduce the pressure to normal pressure within 0.5 seconds. The sliding clamp returns to its initial position under the action of the return spring. Its retraction speed can be controlled within the range of 10-20mm / s by the throttle valve. Through the closed-loop control algorithm, the clamping force adjustment accuracy can reach ±2N, and the position repeatability accuracy is controlled within ±0.01mm.

[0040] In some embodiments, the process of simulating the clamping force process by finite element simulation and establishing a mapping model between the clamping force and the deformation can be seen in Figure 3 As shown, it can be summarized as follows: 1) Establish a finite element model, set the base and clamp as rigid bodies, and the thin-walled parts as isotropic elastic bodies; 2) Constrain all degrees of freedom of the base and the fixed clamp, apply load to the sliding clamp; set all contacts between the thin-walled part and the base, the sliding clamp, and the fixed clamp to surface-to-surface friction contact; 3) The deformation results under different material allowances and clamping forces are obtained through finite element simulation, and a mapping model is established based on this.

[0041] The base and clamp are set as rigid bodies, which can eliminate the interference of the fixture's own deformation on the simulation results. For example, the rigid body properties are defined by steel parameters with a Young's modulus exceeding 200GPa. When thin-walled parts are defined as isotropic elastic bodies, their actual elastic modulus, Poisson's ratio and other material parameters need to be input. For example, aluminum alloy materials can be set to an elastic modulus of 70GPa and a Poisson's ratio of 0.33. The load applied to the sliding clamp needs to match the actual output pressure range of the pneumatic clamp. For example, the loading force range is set to 500N to 3000N, and dynamic loading is performed in steps of 0.1 seconds. The friction coefficient of surface-to-surface friction contact needs to be set according to the surface roughness of the fixture. For example, the friction coefficient of the fine-machined fixture surface is 0.1-0.15, and that of the rough-machined surface is 0.2-0.25.

[0042] During the finite element model construction process, all degrees of freedom (DOFs) of the base and fixed clamp are constrained using fixed support boundary conditions. For example, translational and rotational DOFs in the X / Y / Z directions are constrained in the 3D coordinate system. The load applied to the sliding clamp must align with the actual motion of the pneumatic clamp, for example, applying a linearly increasing pressure load along the positive X-axis. A penalty function method is used to address contact nonlinearity at the interface between the thin-walled part and the clamp, with the contact stiffness factor set to 1%-5% of the material elastic modulus. The friction contact model uses the Coulomb friction formula, and the difference between the static and kinetic friction coefficients is kept within 0.02. A parametric sweep is used to simulate the material allowance and clamping force. For example, the material allowance is decreased from 5mm to 1mm in 0.5mm increments, while the clamping force is increased from 500N to 3000N in 100N steps. This generates a 3D data matrix containing the material allowance, clamping force, and deformation, representing various simulated deformation contours. This data matrix (deformation cloud) is fitted to a quadratic surface equation using the least squares method, forming a quantitative mapping relationship between clamping force and deformation. The goodness of fit must reach or exceed 0.95. The resulting mapping model can accurately predict the deformation of thin-walled parts at different processing stages, providing a reliable basis for dynamically adjusting clamping force.

[0043] In one possible implementation, the initial material allowance of the thin-walled part can be set, for example, from 0 mm to 10 mm, in 0.5 mm intervals. For each material allowance, different clamping forces are applied, and the maximum deformation at the center of the thin-walled part is recorded. This method can generate a series of corresponding data between clamping force, material allowance, and deformation. Using this data, a mapping model between clamping force and deformation can be established. For example, multiple regression analysis or machine learning algorithms, such as support vector regression (SVR) or neural networks, can be used to fit these data points, resulting in a mathematical model capable of predicting deformation under any material allowance and clamping force.

[0044] In a possible implementation, the process of establishing the mapping model can be implemented as follows: A. Import the thin-walled part model into the finite element simulation model and construct the original data set [x, y] of different clamping forces under different milling allowances; B. Import the original data set into the finite element simulation model. Through simulation, the deformation results of different clamping forces under different material allowances are obtained. Based on a large number of deformation results, a mapping model between clamping force and deformation is established. The mapping model is as follows:

[0045] Where D represents the deformation, x represents the material allowance, and y represents the clamping force at this material allowance.

[0046] For example, consider a typical thin-walled aerospace component, such as the skin of a certain aircraft wing. Create a raw data set [x, y] for different milling allowances and clamping forces. The milling allowance x can range from 0.5 mm to 5 mm, with a 0.5 mm increment; the clamping force y can range from 100 N to 1000 N, with a 100 N increment. This yields a raw data set containing 90 data points.

[0047] Import the raw data set into a finite element simulation model and perform batch simulations using commercial finite element analysis software such as ANSYS or ABAQUS. The simulations reveal deformation results for different material allowances and clamping forces. For example, for each [x, y] combination, the maximum deformation D at the center of the thin-walled part can be obtained.

[0048] Based on a large number of deformation results, a mapping model D = f(x, y) is established between clamping force and deformation. D represents the deformation, x represents the material allowance, and y represents the clamping force at this material allowance. The specific mapping relationship can be established through regression analysis or machine learning algorithms. For example, a polynomial regression method can be used to obtain a mapping model of the following form: D = a0 + a1x + a2y + a3x^2 + a4y^2 + a5xy Where a0, a1, a2, a3, a4, and a5 are regression coefficients, which can be solved by the least squares method.

[0049] This technical solution systematically constructs raw data sets for different material allowances and clamping forces, allowing for efficient acquisition of a large number of deformation results through batch simulation. The mapping model established based on these results demonstrates clear mathematical relationships, improving model accuracy and comprehensive data coverage. This approach avoids the inefficiencies of traditional manual simulations, provides a reliable mathematical foundation for subsequent clamping force optimization, and contributes to improved clamping force control accuracy and machining quality during thin-walled part machining.

[0050] In some embodiments, the process of obtaining the maximum allowable clamping force under different material allowances based on the mapping model can be summarized as follows: A. Based on the initial machining process parameters, the milling process is divided into layers to determine the milling parameters under different material allowances; B. Based on the dimensional accuracy requirements of the thin-walled part and the milling amount of each layer, reversely calculate the maximum bulge deformation allowed in the middle position of the thin-walled part; the maximum bulge deformation is the maximum deformation within the allowable range of the thickness dimension tolerance; C. Based on the mapping model, the maximum clamping force under maximum bulge deformation with different material allowances is reversely solved.

[0051] In this step, the material allowance during the layered milling process is divided into multiple stages, and each stage corresponds to a specific milling layer. The milling parameters include process parameters such as milling depth and feed speed, and their values ​​can be dynamically matched according to the material removal rate. The calculation of the maximum bulge deformation needs to be combined with the thickness tolerance range of the thin-walled part, and the deformation threshold is derived through reverse engineering methods. For example, when the thickness tolerance is ±0.05mm, the maximum allowable deformation is set to 0.04mm. The inverse solution process of the mapping model converts the deformation threshold into the corresponding clamping force upper limit by establishing an inverse correlation between the deformation and the clamping force. In the specific implementation, it can be achieved by an iterative algorithm or a numerical analysis method.

[0052] Different stages of milling correspond to different material allowance states. Before the start of milling of each layer, based on the stiffness characteristics of the thin-walled part corresponding to the current material allowance and combined with the thickness tolerance index in the dimensional accuracy requirements, the maximum deformation allowed for the processing of this layer is determined through reverse calculation. For example, when the material allowance is reduced to 40% of the original thickness, it is calculated that the maximum bulge deformation allowed in the middle position is 0.03mm. The allowable deformation value is then input into the pre-established mapping model, and the maximum clamping force value corresponding to the allowance state is obtained through reverse solution. This staged dynamic adjustment mechanism ensures that the clamping force always matches the real-time stiffness of the thin-walled part, and continuously keeps the deformation within the tolerance range during the material removal process, effectively avoiding the problem of over-deformation caused by a decrease in stiffness.

[0053] In the aforementioned scheme, due to the dynamic interaction between the milling force and the clamping force, the initially set milling parameters may cause the clamping system to become unstable during specific machining phases. For example, when the milling force exceeds the friction of the clamping system, it may cause workpiece displacement or vibration, thereby affecting machining accuracy. To address this issue, this application further proposes a stability deterministic analysis of clamping stability and optimizes milling parameters based on the analysis results.

[0054] Figure 4The algorithm flow diagram of the method for dynamically adjusting the clamping force of thin-walled parts is listed. The first stage is to select and design the fixture and material model of the thin-walled parts. The thin-walled parts cloud map is meshed and the unit type is determined through finite element analysis. Then, the clamping force is applied to obtain the test deformation data, and a clamping force-deformation mapping model is constructed to calculate the maximum clamping force under the maximum bulge deformation.

[0055] The second stage is the adaptive adjustment logic of the milling force. The process can be summarized as follows: A. Perform milling simulation based on the initial milling process parameters and extract the milling forces in different directions; The initial milling process parameters are set based on historical experience and the geometry and precision of the thin-walled part. After establishing the finite element simulation, the milling simulation is directly performed to obtain the initial milling forces in different directions. Thereafter, the milling forces will be continuously optimized and adjusted using the stability criterion formula.

[0056] B. Based on the milling force and clamping force obtained under different layer material allowances, the clamping stability is analyzed using the stability criterion formula; C. If the clamping of this layer is stable, keep the milling parameters unchanged; if the stability does not meet the requirements, optimize the milling speed and feed speed parameters to adjust the milling force to make the clamping stable; the stability criterion formula is as follows:

[0057] Among them R n is the clamping force, is the friction coefficient between the thin-walled part and the pneumatic fixture, F c To resist the milling force in this direction.

[0058] In one possible implementation, the initial processing parameters can be input into the finite element analysis software to generate three-dimensional force field data including axial cutting force, radial cutting force and tangential cutting force. After the cutting force data of different material allowance layers are extracted, they are input into the stability criterion formula together with the maximum allowable clamping force of the corresponding layer. When the result of the formula calculation is a negative value, the system automatically triggers the parameter optimization algorithm, which reduces the cutting force by reducing the feed speed. For example, the feed speed is adjusted from 200mm / min to 160mm / min, and the spindle speed is increased from 8000rpm to 9200rpm to maintain processing efficiency. The adjusted parameter combination needs to be re-verified for stability until it meets the requirements. This closed-loop control mechanism effectively solves the problem that traditional fixed parameters cannot adapt to the stiffness changes caused by material removal, and through dynamic adjustment, the clamping system is always in a stable state.

[0059] See also Figure 5 In some embodiments, the process of dynamically adjusting the clamping force of the milling process by controlling the pneumatic clamping tooling through PLC can be designed to include the following steps: Step 501, obtaining milling parameters after clamping stability, simulating the removal of different layers of material in computer-aided manufacturing (CAM) software, and calculating the processing time required for milling different layers; Step 502 , by measuring the contact area between the sliding clamp and the thin-walled workpiece in the clamping environment, the air pressure value required by the clamp to apply the corresponding clamping force is calculated; Step 503, based on the processing time of different layers and the required air pressure, the PLC is timed and programmed, and the air pressure value required for removing the next layer of material is automatically adjusted after each layer is processed, so as to control the timing and dynamic adjustment of the clamping force of the thin-walled parts during the milling process.

[0060] Figure 6 A schematic diagram shows a method for dynamically adjusting the clamping force of thin-walled parts. CAM software can simulate the machining process using a layered cutting path planning module. For example, a machining time sequence can be generated by setting the cutting depth for each layer to 0.5-1.2 mm. Contact area measurement can be achieved using laser scanning or pressure-sensitive film. When the contact area decreases to 60%-75% of the initial value, the air pressure value must be recalculated. PLC timing programming can use a time-triggered mode, for example, triggering an air pressure adjustment command when the machining time error for each layer is within ±0.5 seconds. The corresponding relationship between machining time and air pressure value can be established as a two-dimensional array and stored in the PLC controller. For example, the relationship between clamping force and input air pressure, and the relationship between milling parameters and machining time, etc. For example, when the machining time for the third layer is 8 minutes and 30 seconds, the corresponding air pressure value is 0.45 MPa. A linear relationship can be established between the rate of change in the contact area between the sliding clamp and the thin-walled part and the air pressure adjustment amount. For example, for every 10% decrease in contact area, the air pressure decreases by 0.08 MPa.

[0061] After importing optimized milling parameters into the CAM software, the material removal simulation module generates sequential data for layered machining. For example, when machining a thin-walled part with a height of 50 mm, it can be divided into 40 layers, with the machining time for each layer calculated based on the stock removal, feed rate, and spindle speed. A contact area measurement device collects geometric parameters of the clamping interface in real time, and converts this area change into a pressure adjustment using a contact mechanics model. At the completion of the fifth layer, the measurement system detects that the contact area has decreased from the initial 120 mm² to 85 mm². At this point, a preset algorithm calculates that the air pressure needs to be reduced from 0.6 MPa to 0.52 MPa. The PLC control system receives this pressure adjustment command and precisely adjusts the pressure regulating valve 0.5 seconds before machining the sixth layer. This sequential control mechanism forms a closed loop between clamping force adjustment and the material removal process. For example, during machining the last five layers, the clamping force decreases by 0.05 MPa per layer, effectively preventing buckling deformation during the final machining of the thin-walled part. By discretizing the time axis into control nodes corresponding to the number of processing layers, dynamic matching of the clamping force attenuation curve and the workpiece stiffness change curve is achieved, solving the local overload problem caused by adjustment lag in traditional methods.

[0062] Take the machining of an aircraft engine blade as an example. First, the layered machining process is simulated in CAM software, resulting in machining times of 10 minutes, 8 minutes, and 6 minutes per layer. The contact area between the sliding clamp and the blade is then measured at 100 square centimeters. Based on the contact area and clamping force requirements, the corresponding air pressure values ​​are calculated to be 0.5 MPa, 0.4 MPa, and 0.3 MPa, respectively. Finally, these times and pressure values ​​are input into the PLC control program, automatically adjusting the air pressure to 0.5 MPa, 0.4 MPa, and 0.3 MPa at 10, 18, and 24 minutes, respectively.

[0063] The above solution achieves strict synchronization between clamping force adjustment and the material removal phase. By establishing a temporal relationship between the machining process and clamping force adjustment, the problem of delayed clamping force adjustment under dynamic machining conditions is resolved. The machining process is quantified as discrete control nodes on the timeline, providing a timing benchmark for timing adjustment. By accurately inverting the required air pressure value, the clamping force adjustment is ensured to match the actual contact state, avoiding local stress concentration caused by changes in contact area. The clamping force is gradually attenuated as the machining progresses, avoiding response delays caused by manual intervention, thereby maintaining a dynamic balance between clamping stability and machining accuracy as the stiffness of thin-walled parts continues to decrease.

[0064] In the aerospace industry, the use of data-driven PLCs to dynamically adjust the clamping force of thin-walled parts, such as aircraft wing skins and engine blades, is crucial for the manufacture of complex curved parts. These parts are typically large, thin, and easily deformed, requiring extremely high machining precision. In practice, due to the material properties and complex geometry of thin-walled parts, even with dynamic clamping force adjustment, localized stress concentration can still occur. This is because thin-walled parts exhibit significant stiffness variations in different regions. Using a uniform clamping force can result in excessive force and deformation in some areas, while insufficient force in other areas can cause vibration. This localized stress concentration not only affects machining precision but can also lead to microcracks or fatigue damage in thin-walled parts during machining, severely impacting the part's service life and reliability.

[0065] To this end, the present application also provides a partitioned clamping force adjustment system based on multi-point adaptive control, which can be summarized as follows: Partitioned clamping design: The clamping area of ​​thin-walled parts is divided into multiple independently controlled small areas, each equipped with independent pneumatic clamps and pressure sensors. This design allows the system to apply different clamping forces to different parts of the thin-walled parts. Real-time stress monitoring: Install strain gauges or fiber optic strain sensors at key locations on thin-walled parts to monitor the stress distribution of thin-walled parts in real time during processing; these sensors can capture local stress concentrations. Adaptive control algorithm: Develop an adaptive control algorithm based on fuzzy logic and neural networks. This algorithm can quickly calculate the optimal clamping force required for each partition based on real-time monitored stress data and pre-established finite element models; Multi-channel PLC control system: The upgraded PLC control system can control multiple pneumatic clamps simultaneously. The system adjusts the air pressure value of each zone in real time based on the output of the adaptive control algorithm to achieve precise zone clamping force control; Dynamic compensation mechanism: A dynamic compensation mechanism is introduced to automatically adjust the clamping force of each partition according to the changes in material removal during the processing. This mechanism can effectively address the problem of thin-walled parts with changing stiffness during processing. Visual monitoring interface: Design an intuitive visual interface to display the stress distribution and clamping force of each area of ​​the thin-walled part in real time; the operator can monitor the processing process through this interface and perform manual intervention when necessary.

[0066] In one possible embodiment, the clamping area can be divided into independent control units with a side length of 15-30 cm. Each unit is equipped with a pneumatic clamp with a piezoelectric ceramic driver, and the pressure sensor adopts a fiber Bragg grating type with a measurement accuracy of up to ±0.05 MPa. The strain monitoring point spacing is set to 1 / 5-1 / 3 of the characteristic size of the processing area, and the fiber optic strain sensor collects data at a sampling frequency of once per millisecond. The control algorithm integrates an improved TS fuzzy neural network structure. The input layer contains stress gradient, material removal rate and vibration spectrum eigenvalues, and the number of hidden layer nodes is dynamically adjusted according to the number of partitions. The multi-channel PLC system adopts a CAN bus architecture, supports 32 independent air pressure control channels, and the air pressure adjustment resolution reaches 0.01 MPa. The dynamic compensation module has a built-in material stiffness attenuation model, which automatically triggers the clamping force correction calculation every time 1% of the volume of material is removed. The monitoring interface integrates a three-dimensional thermal map display function, and areas with excessive stress are automatically marked as red warnings.

[0067] Specifically, during the engine blade machining process, the clamping surface is first divided into 12 sector-shaped control zones based on the blade profile curvature. When milling enters the blade root transition area, a fiber optic sensor detects that the stress value in the third sector exceeds the threshold of 28 MPa. The control algorithm immediately retrieves the finite element model data for this area. Based on the current cutting depth of 2.3 mm and spindle speed of 8500 rpm, it calculates that the clamping force needs to be reduced from 15.6 MPa to 13.2 MPa. The PLC system adjusts the air pressure valve in the third sector within 50 ms. Simultaneously, due to the reduced stiffness in the seventh sector caused by material removal, the compensation module increases the clamping force from 14.1 MPa to 14.8 MPa. The operator observes through the 3D interface that the stress uniformity index has increased from 0.78 to 0.92, and the vibration amplitude has decreased from 12 μm to 5 μm. This dynamic adjustment mechanism keeps the blade profile error within ±0.03 mm and reduces the standard deviation of the surface residual stress distribution to 7.8 MPa.

[0068] This system effectively addresses the problem of localized stress concentration caused by stiffness differences during thin-walled part machining. The independent control mechanism, combined with real-time stress feedback, enables differentiated clamping force compensation for different rigidity zones, avoiding localized overload or underconstraint caused by uniform clamping force. A dynamic compensation algorithm predicts workpiece stiffness trends based on material removal, proactively adjusting clamping force parameters to prevent deformation accumulation. A visual monitoring system provides transparency into the stress field during machining, providing data support for process optimization and significantly improving the machining accuracy and fatigue life of complex curved thin-walled parts.

[0069] Figure 7 The structural block diagram of the device for dynamically adjusting the clamping force of thin-walled parts provided in an embodiment of the present application is shown. The device includes: Model building module 710, for determining the clamping form and size of the pneumatic clamping fixture according to the size of the thin-walled part, and simulating the clamping force process through finite element simulation to establish a mapping model between the clamping force and deformation; A calculation module 720 is configured to set initial processing parameters according to the size and precision requirements of the thin-walled part, and obtain the maximum allowable clamping force under different material allowances based on a mapping model; Optimization module 730, for performing stability determination analysis on clamping stability and optimizing milling parameters based on the analysis results; The adjustment module 740 is used to obtain in real time the milling process and milling parameters, and to dynamically adjust the clamping force of the milling process by controlling the pneumatic clamping fixture through the PLC.

[0070] It should be noted that the device for dynamically adjusting the clamping force of thin-walled parts provided in the embodiments of the present application is only illustrated by the division of the above-mentioned functional modules / functional units. In actual applications, the above-mentioned functions can be assigned to different functional modules / functional units as needed, that is, the internal structure of the device for dynamically adjusting the clamping force of thin-walled parts can be divided into different functional modules / functional units to complete all or part of the functions described above. In addition, the implementation method of the method for dynamically adjusting the clamping force of thin-walled parts provided in the above-mentioned method embodiment and the implementation method of the device for dynamically adjusting the clamping force of thin-walled parts provided in this embodiment belong to the same concept. The specific implementation process of the device for dynamically adjusting the clamping force of thin-walled parts provided in this embodiment is detailed in the above-mentioned method embodiment and will not be repeated here.

[0071] Figure 8The following is a block diagram of the structure of a computer device provided by an exemplary embodiment of the present application. The computer device is a desktop computer, a laptop computer, a PDA, a cloud server, and the like. The computer device may include, but is not limited to, a processor and a memory. The processor and the memory may be connected via a bus or other means. The processor may be a central processing unit (CPU). The processor may also be other general-purpose processors, digital signal processors (DSP), application-specific integrated circuits (ASIC), field-programmable gate arrays (FPGA) or other programmable logic devices, graphics processing units (GPU), embedded neural network processors (NPU) or other dedicated deep learning coprocessors, discrete gate or transistor logic devices, discrete hardware components, or a combination of the above chips.

[0072] The processor may include one or more processing cores, such as a quad-core processor or an octa-core processor. The processor may be implemented in at least one of the following hardware forms: a DSP (Digital Signal Processing), an FPGA (Field-Programmable Gate Array), or a PLA (Programmable Logic Array). The processor may also include a main processor and a coprocessor. The main processor is used to process data while awake, also known as a CPU (Central Processing Unit); the coprocessor is a low-power processor used to process data while in standby mode. In some embodiments, the processor may integrate a graphics processing unit (GPU), which is responsible for rendering and drawing content displayed on the display. In some embodiments, the processor may also include an artificial intelligence (AI) processor, which is used to handle computational operations related to machine learning.

[0073] As a non-transient computer-readable storage medium, the memory can be used to store non-transient software programs, non-transient computer executable programs and modules, such as program instructions / modules corresponding to the methods in the above-mentioned embodiments of the present application. The processor executes various functional applications and data processing of the processor by running the non-transient software programs, instructions and modules stored in the memory, that is, the method in the above-mentioned method embodiment is implemented. The memory may include a program storage area and a data storage area, wherein the program storage area may store an operating system, an application required for at least one function; the data storage area may store data created by the processor, etc. In addition, the memory may include a high-speed random access memory, and may also include a non-transient memory, such as at least one disk storage device, a flash memory device, or other non-transient solid-state storage device. In some embodiments, the memory may optionally include a memory remotely arranged relative to the processor, and these remote memories may be connected to the processor via a network. Examples of the above-mentioned network include, but are not limited to, the Internet, an intranet, a local area network, a mobile communication network and a combination thereof.

[0074] In some embodiments, the computer device may optionally include a peripheral device interface and at least one peripheral device. The processor, memory, and peripheral device interface may be connected via a bus or signal lines. Each peripheral device may be connected to the peripheral device interface via a bus, signal lines, or circuit boards. Specifically, the peripheral device includes at least one of a radio frequency circuit, a display screen, and a keyboard.

[0075] The peripheral device interface can be used to connect at least one I / O (Input / Output)-related peripheral device to the processor and memory. In some embodiments, the processor, memory, and peripheral device interface are integrated on the same chip or circuit board. In other embodiments, any one or two of the processor, memory, and peripheral device interface can be implemented on separate chips or circuit boards, although this embodiment is not limited to this.

[0076] The display screen is used to display a UI (User Interface). The UI may include graphics, text, icons, videos, or any combination thereof. When the display screen is a touch screen, it also has the ability to capture touch signals on or above the surface of the display screen. The touch signals can be input as control signals to a processor for processing. In this case, the display screen can also be used to provide virtual buttons and / or virtual keyboards, also known as soft buttons and / or soft keyboards. In some embodiments, there can be one display screen, disposed on the front panel of the computer device; in other embodiments, there can be at least two display screens, disposed on different surfaces of the computer device or in a foldable design; in still other embodiments, the display screen can be a flexible display screen, disposed on a curved or foldable surface of the computer device. Furthermore, the display screen can be configured as a non-rectangular, irregular shape, also known as a special-shaped screen. The display screen can be made of materials such as LCD (Liquid Crystal Display) and OLED (Organic Light-Emitting Diode).

[0077] A power supply is used to power various components in computer equipment. The power supply can be AC, DC, disposable batteries, or rechargeable batteries. When the power supply includes a rechargeable battery, it can be wired or wirelessly rechargeable. A wired rechargeable battery is charged via a wired line, while a wireless rechargeable battery is charged via a wireless coil. The rechargeable battery can also support fast charging technology.

[0078] Those skilled in the art will understand that the structure shown in this embodiment does not constitute a limitation on the computer device, and may include more or fewer components than shown in the figure, or combine certain components, or adopt a different component arrangement.

[0079] The embodiment of the present application also discloses a computer-readable storage medium. Specifically, the computer-readable storage medium is used to store a computer program, and when the computer program is executed by the processor, the method in the above-mentioned method implementation is implemented. Those skilled in the art will understand that all or part of the processes in the above-mentioned method implementation of the present application can be completed by instructing the relevant hardware through a computer program. The program can be stored in a computer-readable storage medium, and when the program is executed, it can include the processes of the implementation of the above-mentioned methods. Among them, the storage medium can be a magnetic disk, an optical disk, a read-only memory (ROM), a random access memory (RAM), a flash memory (Flash Memory), a hard disk drive (HDD) or a solid-state drive (SSD), etc.; the storage medium can also include a combination of the above-mentioned types of memory.

[0080] This specific embodiment is merely an explanation of the present invention and is not intended to limit the present invention. After reading this specification, those skilled in the art may make non-creative modifications to this embodiment as needed. However, as long as such modifications are within the scope of the claims of the present invention, they are protected by patent law.

Claims

1. A method for dynamically adjusting the clamping force of thin-walled parts, characterized in that: The method comprises: The clamping form and size of the pneumatic fixture are determined according to the size of the thin-walled workpiece. The clamping force process is simulated through finite element simulation to establish a mapping model between the clamping force and deformation. Initial machining process parameters are set according to the size and precision requirements of the thin-walled part, and the maximum clamping force allowed under different material allowances is obtained based on the mapping model; Conduct stability analysis on clamping stability and optimize milling parameters based on the analysis results; According to the milling process and milling parameters, the clamping force of the milling process is dynamically adjusted regularly by controlling the pneumatic clamping tooling through the PLC.

2. The method according to claim 1, characterized in that The cylinder of the pneumatic clamping tool is connected to the sliding clamping block through a connecting rod. The sliding clamping block is slidably arranged on one side of the base, and a fixed clamping block corresponding to the sliding clamping block is arranged on the other side of the base; The PLC controls the air regulating valve to adjust the output pressure of the cylinder, and drives the sliding clamp block to approach the fixed clamp block through the connecting rod to clamp the thin-walled part, or drives the sliding clamp block away from the fixed clamp block to release the thin-walled part.

3. The method according to claim 1, characterized in that The finite element simulation is used to simulate the clamping force process and establish a mapping model between the clamping force and the deformation, including: A finite element model is established, wherein the base and the clamping block are set as rigid bodies, and the thin-walled member is set as an isotropic elastic body; All degrees of freedom of the base and the fixed clamp are constrained, and a load is applied to the sliding clamp; all contacts between the thin-walled member and the base, the sliding clamp, and the fixed clamp are set to surface-to-surface friction contacts; The deformation results under different material allowances and clamping forces are obtained through finite element simulation, and the mapping model is established based on them.

4. The method according to claim 3, characterized in that The deformation results under different material allowances and clamping forces are obtained by finite element simulation, and the mapping model is established based on the obtained results, including: Import the thin-walled part model into the finite element simulation model to construct the original data set [x, y] of different clamping forces under different milling allowances; The original data set is imported into the finite element simulation model. The deformation results of different clamping forces under different material allowances are obtained through simulation. Based on a large number of deformation results, a mapping model between clamping force and deformation is established. The mapping model is as follows: Where D represents the deformation, x represents the material allowance, and y represents the clamping force at this material allowance.

5. The method according to claim 4, characterized in that The maximum clamping force allowed under different material allowances is obtained based on the mapping model, including: Based on the initial machining process parameters, the milling process is divided into layers to determine the milling parameters under different material allowances; According to the dimensional accuracy requirements of the thin-walled part and the value of the milling amount of each layer, the maximum bulge deformation allowed at the middle position of the thin-walled part is reversely calculated; the maximum bulge deformation is the maximum deformation within the allowable range of the thickness dimension tolerance; The maximum clamping force under the maximum bulge deformation with different material allowances is reversely solved based on the mapping model.

6. The method according to any one of claims 1 to 5, characterized in that: The stability determination analysis of the clamping stability and the optimization of the milling parameters according to the analysis results include: Perform milling simulation based on initial milling process parameters and extract milling forces in different directions; Based on the milling force and clamping force obtained under different layer material allowances, the clamping stability is analyzed using the stability criterion formula; If the clamping of this layer is stable, the milling parameters are kept unchanged; if the stability does not meet the requirements, the milling speed and feed speed parameters are optimized to adjust the milling force to make the clamping stable; the stability criterion formula is as follows: Among them R n is the clamping force, is the friction coefficient between the thin-walled part and the pneumatic fixture, F c To resist the milling force in this direction.

7. The method according to claim 6, characterized in that The real-time acquisition is based on the milling process and milling parameters, and the clamping force of the milling process is dynamically adjusted by controlling the pneumatic clamping fixture through the PLC, including: After obtaining the milling parameters for clamping stability, simulate the material removal of different layers in computer-aided manufacturing (CAM) software and calculate the processing time required for milling different layers. By measuring the contact area between the sliding clamp and the thin-walled workpiece in the clamping environment, the air pressure required by the clamp to apply the corresponding clamping force is calculated; The PLC is timed and programmed based on the processing time of different layers and the required air pressure. After each layer is processed, the air pressure required for removing the next layer of material is automatically adjusted to control the timing and dynamic adjustment of the clamping force of the thin-walled part during the milling process.

8. A device for dynamically adjusting the clamping force of thin-walled parts, characterized in that: The device comprises: The model building module is used to determine the clamping form and size of the pneumatic fixture according to the size of the thin-walled part, simulate the clamping force process through finite element simulation, and establish a mapping model between the clamping force and deformation; a calculation module, configured to set initial processing parameters according to the size and precision requirements of the thin-walled part, and obtain the maximum allowable clamping force under different material allowances based on a mapping model; Optimization module, used to perform stability analysis on clamping stability and optimize milling parameters based on the analysis results; The adjustment module is used to obtain in real time according to the milling process and milling parameters, and to control the pneumatic clamping tooling to dynamically adjust the clamping force of the milling process through PLC.

9. A computer device, characterized in that: The computer device includes a processor and a memory, wherein the memory stores at least one instruction, at least one program, a code set or an instruction set, and the at least one instruction, the at least one program, the code set or the instruction set is loaded and executed by the processor to implement the method for dynamically adjusting the clamping force of thin-walled parts as described in any one of claims 1 to 7.

10. A computer-readable storage medium, characterized in that The readable storage medium stores at least one instruction, at least one program, a code set or an instruction set, and the at least one instruction, the at least one program, the code set or the instruction set are loaded and executed by the processor to implement the method for dynamically adjusting the clamping force of thin-walled parts as described in any one of claims 1 to 7.

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