Method and device for controlling depth of automatic countersinking for laminated components

Abstract

The present invention relates to the field of aerospace product assembly technology, and in particular to a method and device for controlling the countersink depth in the automated hole making process of a laminated component, wherein the method comprises: constructing a cutting force model and a workpiece deformation model of the countersink process to determine an iterative strategy for machining deformation compensation; executing the iterative strategy for machining deformation compensation to calculate the displacement difference between the pressure ring position and the hole making center position during the machining process to construct feedforward compensation; collecting the displacement of the workpiece at the pressure ring position during the machining process based on a displacement sensor set at the pressure ring position to construct feedback compensation; and jointly compensating the nominal feed depth of the tool through feedforward compensation and feedback compensation to obtain a given feed depth of the tool. Thus, the problems that the prior art ignores the difference between the deformation of the workpiece at the clamping position and the actual hole making center position during the hole making process, and the deformation of the workpiece at the actual hole making position is difficult to be accurately measured in real time are solved.

Description

Technical Field

[0001] The invention relates to the technical field of aerospace product assembly, and in particular to a method and a device for controlling countersink depth in an automated hole making process of a laminated component. Background Art

[0002] There are a large number of structural parts positioning and connection requirements in aircraft assembly, so hole making in laminated structures is very common, and drilling, reaming and countersinking processing technologies are used. In order to improve the hole making quality and processing efficiency, the automated one-knife hole making process has been widely studied. Countersinking is the key to the hole making process of laminated components. Excessive countersinking depth will directly affect the assembly quality and even the performance of the aircraft. In the automatic hole making process of laminated components, the workpiece will be deformed due to the influence of cutting force, clamping force, etc. If the tool is processed according to the nominal feed depth, the countersink depth will have a large error, so certain compensation measures need to be taken to complete the control. Existing methods mostly use the displacement compensation scheme of a unidirectional clamping device. A pressure ring is installed at the end of the hole making device to clamp the laminate to reduce the gap between layers, and a displacement sensor is installed on the pressure ring to directly measure the deformation of the workpiece to achieve feedback compensation of the tool feed depth.

[0003] However, the current automatic countersink depth control method simply uses a pressure ring to detect the deformation of the workpiece to achieve tool feed displacement compensation, and does not consider the difference in the deformation of the workpiece at the clamping position and the actual hole center position during the hole making process. In addition, the deformation of the workpiece at the actual hole making position is difficult to be accurately measured in real time, which leads to a systematic error in this method. The systematic error is related to the curvature and rigidity of the actual hole making position. Summary of the invention

[0004] The present invention provides a countersink depth control method and device for an automated hole making process for laminated components, so as to solve the problems that the prior art ignores the difference between the deformation of the workpiece at the clamping position and the actual hole making center position during the hole making process, and the deformation of the workpiece at the actual hole making position is difficult to be accurately measured in real time, thereby improving the countersink depth control accuracy of the automated hole making process for laminated components.

[0005] The first aspect of the present invention provides a method for controlling the countersink depth in an automated hole-making process for a laminated component, comprising the following steps: constructing a cutting force model and a workpiece deformation model for the countersinking process; determining an iterative strategy for machining deformation compensation according to the cutting force model and the workpiece deformation model; executing the iterative strategy for machining deformation compensation to calculate the displacement difference between a pressure ring position and a hole-making center position during machining to construct feedforward compensation; collecting the displacement of the workpiece at the pressure ring position during machining based on a displacement sensor provided at the pressure ring position to construct feedback compensation; and jointly compensating the nominal feed depth of the tool through the feedforward compensation and the feedback compensation to obtain a given feed depth of the tool.

[0006] Optionally, before determining the iterative strategy for the machining deformation compensation amount, it also includes: setting a force sensor in the tool to obtain the hole-making axial force during the machining process; judging whether the wear of the tool exceeds a preset threshold value according to the hole-making axial force; if it does not exceed the preset threshold value, determining the iterative strategy for the machining deformation compensation amount using the cutting force model and the workpiece deformation model; if it exceeds the preset threshold value, correcting the cutting force model according to the hole-making axial force to obtain a new cutting force model, and determining the iterative strategy for the machining deformation compensation amount using the new cutting force model and the workpiece deformation model.

[0007] Optionally, the machining deformation compensation iterative strategy includes an inner layer loop strategy and an outer layer loop strategy, wherein, when executing the inner layer loop strategy, the coupling relationship between the cutting force and the workpiece deformation is determined according to the cutting force model and the workpiece deformation model, and the deformation displacement of two positions after the machining is completed is iteratively calculated according to the coupling relationship; when executing the outer layer loop strategy, the nominal feed depth is iteratively compensated using the deformation displacement of the two positions until the iteration stop condition is reached to obtain the displacement difference.

[0008] Optionally, the feed displacement of the tool is jointly compensated by the feedforward compensation and the feedback compensation to obtain a given feed depth of the tool, including: using the displacement difference obtained by the feedforward compensation and the displacement obtained by the feedback compensation to jointly iteratively compensate the nominal feed depth of the tool until a preset convergence condition is reached, stopping the machining process, and obtaining the given feed depth.

[0009] The second aspect of the present invention provides a countersink depth control device for an automated hole making process of a laminated component, comprising: a model building module, for building a cutting force model and a workpiece deformation model of the countersink process; a determination module, for determining an iterative strategy for machining deformation compensation according to the cutting force model and the workpiece deformation model; a feedforward compensation building module, for executing the iterative strategy for machining deformation compensation to calculate the displacement difference between a pressure ring position and a hole making center position during machining, so as to build feedforward compensation; a feedback compensation building module, for collecting the displacement of the workpiece at the pressure ring position during machining based on a displacement sensor provided at the pressure ring position, so as to build feedback compensation; and a joint compensation module, for jointly compensating the nominal feed depth of the tool through the feedforward compensation and the feedback compensation, so as to obtain a given feed depth of the tool.

[0010] Optionally, it also includes:

[0011] An updating module is used to set a force sensor in the tool to obtain the hole-making axial force during the machining process, and judge whether the wear of the tool exceeds a preset threshold value according to the hole-making axial force; if it does not exceed the preset threshold value, the cutting force model and the workpiece deformation model are used to determine the iterative strategy of the machining deformation compensation amount; if it exceeds the preset threshold value, the cutting force model is corrected according to the hole-making axial force to obtain a new cutting force model, and the new cutting force model and the workpiece deformation model are used to determine the iterative strategy of the machining deformation compensation amount.

[0012] Optionally, the machining deformation compensation amount iteration strategy includes an inner layer loop strategy and an outer layer loop strategy, wherein:

[0013] In the case of executing the inner layer circulation strategy, the coupling relationship between the cutting force and the workpiece deformation is determined according to the cutting force model and the workpiece deformation model, and the deformation displacements of two positions after the machining is completed are iteratively calculated according to the coupling relationship;

[0014] When the outer layer circulation strategy is executed, the nominal feed depth is iteratively compensated using the deformation displacements of the two positions until an iteration stop condition is reached to obtain the displacement difference.

[0015] Optionally, the common compensation module is specifically used for:

[0016] The displacement difference obtained by the feedforward compensation and the displacement amount obtained by the feedback compensation are used to jointly iteratively compensate the nominal feed depth of the tool until a preset convergence condition is reached, the machining process is stopped, and the given feed depth is obtained.

[0017] The countersink depth control method and device for the automated hole making process of laminated components proposed in the embodiments of the present invention utilize a cutting force model and a workpiece deformation model to add a feedforward link in the countersink depth control, thereby eliminating the system error caused by the difference between the workpiece deformation at the pressure ring position and the hole making position, and utilizing axial force detection to eliminate the influence of tool wear, thereby improving the countersink depth accuracy of the automated hole making process of laminated components.

[0018] Additional aspects and advantages of the present invention will be given in part in the following description and in part will be obvious from the following description, or will be learned through practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] The above and / or additional aspects and advantages of the present invention will become apparent and easily understood from the following description of the embodiments in conjunction with the accompanying drawings, in which:

[0020] Figure 1 A flow chart of a method for controlling countersink depth in an automated hole making process for a laminated component provided by an embodiment of the present invention;

[0021] Figure 2 A control block diagram combining feedforward compensation and feedback compensation provided by an embodiment of the present invention;

[0022] Figure 3 A schematic diagram of an iterative solution calculation method for compensation provided by an embodiment of the present invention;

[0023] Figure 4 A block diagram of a countersink depth control device for an automated hole making process of a laminated component provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0024] Embodiments of the present invention are described in detail below, examples of which are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are intended to be used to explain the present invention, and should not be construed as limiting the present invention.

[0025] The following describes a method and device for controlling countersink depth in an automated hole-making process for a laminated component according to an embodiment of the present invention with reference to the accompanying drawings.

[0026] Figure 1 A schematic flow chart of a method for controlling countersink depth in an automated hole making process for a laminated component provided by an embodiment of the present invention.

[0027] like Figure 1 As shown, the method for controlling the countersink depth in the automatic hole making process of the laminated component includes the following steps:

[0028] In step S101, a cutting force model and a workpiece deformation model of the countersinking process are constructed.

[0029] Specifically, existing research can be used to establish a theoretical model of cutting force and workpiece deformation to obtain a cutting force model and a workpiece deformation model. Before processing begins, the parameters of the cutting force model and the workpiece deformation model can be calculated based on factors such as the hole-making tool material and geometric parameters, the workpiece material and structure, and the clamping method.

[0030] In step S102, a machining deformation compensation amount iteration strategy is determined according to the cutting force model and the workpiece deformation model.

[0031] Furthermore, in one embodiment of the present invention, before determining the iterative strategy of the machining deformation compensation amount, the method further includes:

[0032] A force sensor is set in the tool to obtain the hole-making axial force during the machining process;

[0033] Judging whether the tool wear exceeds a preset threshold value based on the hole-making axial force;

[0034] If the preset threshold is not exceeded, the iterative strategy of machining deformation compensation is determined using the cutting force model and the workpiece deformation model;

[0035] If it exceeds the preset threshold, the cutting force model is corrected according to the hole-making axial force to obtain a new cutting force model, and the new cutting force model and workpiece deformation model are used to determine the iterative strategy of machining deformation compensation.

[0036] Specifically, based on the force sensor set in the preset hole-making equipment, the hole-making axial force in the processing process is obtained, and whether the wear of the tool exceeds the preset threshold value is judged according to the hole-making axial force. If not, there is no need to correct the parameters of the cutting force model. The corresponding relationship between the deformation of the workpiece at the clamping position and the hole-making position under the action of the cutting force and the clamping force is determined by using the various parameters of the cutting force model and the various parameters of the workpiece deformation model, and the iterative strategy of the processing deformation compensation amount is determined. If it exceeds, the tool has been processed continuously and is severely worn. It is necessary to correct the parameters of the cutting force model according to the hole-making axial force to eliminate the influence of tool wear on the calculation accuracy of the cutting force, and obtain a new cutting force model. The various parameters of the new cutting force model and the various parameters of the workpiece deformation model are used to determine the iterative strategy of the processing deformation compensation amount, thereby improving the accuracy of the feedforward link.

[0037] Among them, if the tool is a new tool, there is no need to obtain the hole-making axial force during the machining process, and the cutting force model does not need to be corrected by default. The cutting force model and the workpiece deformation model are used to determine the iterative strategy of the machining deformation compensation amount.

[0038] Among them, the iterative strategy for machining deformation compensation includes an inner loop strategy and an outer loop strategy. When the inner loop strategy is executed, the coupling relationship between the cutting force and the workpiece deformation is determined according to the cutting force model and the workpiece deformation model, and the deformation displacement of the two positions after machining is completed is iteratively calculated according to the coupling relationship; when the outer loop strategy is executed, the nominal feed depth is iteratively compensated using the deformation displacement of the two positions until the iteration stop condition is reached to obtain the displacement difference.

[0039] In step S103, the machining deformation compensation amount iteration strategy is executed to calculate the displacement difference between the pressing ring position and the hole making center position during the machining process to construct a feedforward compensation.

[0040] Specifically, the hole position, hole diameter, pocket depth, laminated structure and material properties are determined according to the workpiece deformation model; the hole making tool, cutting speed, feed rate and nominal countersink depth are determined in combination with the hole making process; and the inner layer loop of the machining deformation compensation iterative strategy utilizes the coupling relationship between the cutting force and the workpiece deformation to iteratively calculate the deformation at a certain feed depth; the outer layer loop analyzes the interaction between the cutting force and deformation in the compensation process, and the deformation in the inner layer loop is added to the feed compensation until convergence; the compensation amount, that is, the displacement difference between the pressure ring position and the hole making position when the machining is completed, is iteratively calculated to perform feedforward compensation on the nominal feed depth of the tool.

[0041] In step S104, the displacement of the workpiece at the pressing ring position during the machining process is collected based on the displacement sensor arranged at the pressing ring position to construct feedback compensation.

[0042] Specifically, during the machining process, the displacement of the workpiece at the position of the pressing ring is measured by the pressing ring displacement sensor to perform feedback compensation on the nominal feed depth of the tool.

[0043] In step S105, the nominal feed depth of the tool is compensated together by feedforward compensation and feedback compensation to obtain a given feed depth of the tool.

[0044] Specifically, Figure 2 As shown in the figure, the displacement difference obtained by feedforward compensation and the displacement obtained by feedback compensation are used to jointly iteratively compensate the nominal feed depth of the tool, that is, the tool feed depth is updated and input into the position controller until the preset convergence condition is reached, and the machining process is stopped, thereby eliminating the system error caused by the difference in workpiece deformation between the clamping position and the hole making position, obtaining a given feed depth, and effectively improving the machining accuracy of the countersink depth.

[0045] The following takes an aluminum alloy / aluminum alloy laminated rectangular flat plate workpiece as an example to further illustrate the countersink depth control method in the automated hole making process of a laminated component proposed in an embodiment of the present invention.

[0046] According to existing research, the microelement analysis method can be used to analyze the cutting force in the cutting deformation zone, and then the model can be established by integration to obtain the cutting force model. Similarly, the shell mechanics theory can be used to analyze the influence of the stacking interaction force, the clamping force and the cutting force on the deformation of the top layer of the stack, and the workpiece deformation model can be established.

[0047] For aluminum alloy / aluminum alloy stacking, the cutting force model can be established as follows:

[0048] F=2(V y W y +V z W z )(C T -w)

[0049]

[0050]

[0051] Where F is the countersink cutting force, V y , W y 、V z , W z Indicates different cutting force coefficients, C T represents the nominal feed depth of the tool, w is the axial deformation of the workpiece, and the difference between the two is the actual cutting depth. s is the shear strength of the workpiece material, γ0 is the blade rake angle, β is the friction angle, φ is the shear angle, and a c is the cutting thickness of the countersink, and ρ is the half apex angle of the countersink. f is the feed rate, n c is the tool speed and d is the hole diameter.

[0052] Ignoring the interlayer contact force of the stack and considering the deformation of the top layer, the workpiece deformation model can be established as follows:

[0053] w(ξ,η|x,y)=w P (ξ,η|x,y)+w F (ξ,η|x,y)

[0054]

[0055] In the formula, w P represents the deformation caused by the compaction force, w F represents the deformation caused by the axial cutting force, (ξ,η) is the center of force action, which is the hole-making position in the specific working condition, (x,y) is the solution position of the deformation, which can be adjusted as needed, P is the clamping force, and F is the axial cutting force. is the bending stiffness of the upper plate, E is the elastic modulus, ν is the Poisson's ratio, and h is the plate thickness. R is the outer diameter of the pressure ring, r is the inner diameter of the pressure ring, and a and b represent the length and width of the laminated rectangular plate, respectively.

[0056] If a new tool is used, the coefficient 2 (V y W y +V z W z ) can be calculated using the formula; if the tool is already worn, the modeling result will be inaccurate. Therefore, for tools that are in continuous use, the force sensor can be used to detect the axial cutting force at the end of each countersinking, and the actual cutting depth at this time is considered to be the required countersinking depth. Take the data of the last three processing times and calculate the average value to obtain the coefficient 2 (V y W y +Vz W z ) value, and the coefficient is updated after each processing to eliminate the influence of tool wear on the calculation accuracy of workpiece deformation and obtain a new cutting force model.

[0057] After the process parameters such as tool and workpiece characteristics are determined, the axial cutting force F = F (C T -w) is determined by the given feed depth CT and the workpiece deformation w, and has a monotonically positive correlation with the actual cutting depth CT-w, while the deformation w=w(ξ,η|x,y) is determined by the hole making position (ξ,η) and the calculation position (x,y). After determining the two positions, the clamping force is considered unchanged during the processing, and the deformation model is simplified to w=w(F), which is determined by the axial cutting force and increases monotonically with the increase of the cutting force. It can be seen that the cutting force and the deformation are coupled with each other and it is difficult to solve directly.

[0058] Use Figure 3 The solution method shown in the figure is used to solve the compensation amount after the process parameters are determined. i,j and F i,j is the iterative process quantity of workpiece deformation and axial cutting force, CT j is the iterative process quantity of the tool feed depth, H is the nominal feed depth of the tool (when the workpiece is completely free of deformation, H is the ideal feed depth), D j is the compensation amount of feed amount, and ε1 and ε2 are parameters that determine the iteration accuracy.

[0059] like Figure 3 As shown in the figure, the solution process consists of two loops, the inner loop and the outer loop. In the inner loop, the feed depth CT is given. j , iteratively calculate the deformation and cutting force. If the difference between the deformation of the two cycles is less than ε1, it means that the calculation has converged. At this time, the final deformation w at the hole position can be accurately obtained. i,j , based on which the compensation amount is obtained as D j-1 After compensating the corresponding error during the countersinking process, new deformation and countersinking errors will be generated, so an outer loop is required. j =w i,j , w i,j As the compensation amount for the jth cycle, the tool feed depth is corrected to CT j+1 =H+D j , update the relevant parameters of the outer loop accordingly, and enter the inner loop again until convergence. When the outer loop converges, output the final compensation amount D j and feed depth CT j When the model is accurate enough, the countersink depth error can be controlled within ε2 by using the compensated feed depth.

[0060] It is worth noting that the deformation model w = w(ξ,η|x,y) can accept the situation where the hole making position is different from the calculated position. Therefore, it can be used for working conditions where the pressure ring position (corresponding to the calculated position) is different from the hole making position to eliminate system errors.

[0061] Before the processing starts, the calculated position (x, y) is brought into the hole making position and the pressure ring position respectively. The above iterative algorithm can be used to calculate the deformation displacement w of the two positions when the processing is completed. o and w r , subtracting the two can get the displacement difference w d =w o -w r , thus obtaining the feedforward amount that eliminates the feedback system error.

[0062] During the processing, the construction Figure 2 The control loop shown in the figure combines the feedforward value calculated before processing and the pressure ring deformation displacement feedback value w obtained by real-time detection during processing. pr The feed depth input to the motion controller is compensated as CT b =CT0+w pr +w d .

[0063] It should be noted that for more complex structures that are not flat plates, if the model of the axial cutting force and deformation is difficult to accurately establish, the empirical formula for the deformation of the workpiece at the hole-making position of the corresponding structure under different process parameters and tool wear conditions can be summarized by finite element analysis and other methods, and the feedforward amount can be calculated using the empirical formula before processing. The present invention provides a method for establishing a feedforward controller when the axial cutting force and deformation model can be established, but the specific feedforward controller construction method cannot be used as a limitation on the control method combining feedforward and feedback described in the present invention, and should also be regarded as a protected embodiment.

[0064] According to the countersink depth control method for the automated hole making process of laminated components proposed in an embodiment of the present invention, a cutting force model and a workpiece deformation model are used to add a feedforward link in the countersink depth control to eliminate the system error caused by the difference between the workpiece deformation at the pressure ring position and the hole making position, and axial force detection is used to eliminate the influence of tool wear, thereby improving the countersink depth accuracy of the automated hole making process of laminated components.

[0065] Next, a countersink depth control device for an automated hole making process for a laminated component according to an embodiment of the present invention will be described with reference to the accompanying drawings.

[0066] Figure 4 It is a block diagram of a device for controlling countersink depth in an automated hole making process for a laminated component according to an embodiment of the present invention.

[0067] like Figure 4As shown, the countersink depth control device 40 for the automatic hole making process of the laminated component includes: a model building module 401, a determination module 402, a feedforward compensation building module 403, a feedback compensation building module 404 and a common compensation module 405.

[0068] Among them, the model construction module 401 is used to construct the cutting force model and workpiece deformation model of the countersinking process. The determination module 402 is used to determine the iterative strategy of the machining deformation compensation amount according to the cutting force model and the workpiece deformation model. The feedforward compensation construction module 403 is used to execute the iterative strategy of the machining deformation compensation amount to calculate the displacement difference between the pressure ring position and the hole making center position during the machining process to construct the feedforward compensation. The feedback compensation construction module 404 is used to collect the displacement of the workpiece at the pressure ring position during the machining process based on the displacement sensor set at the pressure ring position to construct the feedback compensation. The joint compensation module 405 is used to jointly compensate the nominal feed depth of the tool through feedforward compensation and feedback compensation to obtain the given feed depth of the tool.

[0069] Furthermore, in one embodiment of the present invention, it also includes: an updating module, which is used to set a force sensor in the tool to obtain the hole-making axial force during the machining process, and judge whether the wear of the tool exceeds a preset threshold based on the hole-making axial force; if it does not exceed the preset threshold, the cutting force model and the workpiece deformation model are used to determine the iterative strategy of the machining deformation compensation amount; if it exceeds the preset threshold, the cutting force model is corrected according to the hole-making axial force to obtain a new cutting force model, and the new cutting force model and the workpiece deformation model are used to determine the iterative strategy of the machining deformation compensation amount.

[0070] Further, in one embodiment of the present invention, the machining deformation compensation amount iteration strategy includes an inner loop strategy and an outer loop strategy, wherein:

[0071] When the inner layer loop strategy is executed, the coupling relationship between the cutting force and the workpiece deformation is determined according to the cutting force model and the workpiece deformation model, and the deformation displacement of the two positions after the machining is completed is iteratively calculated according to the coupling relationship;

[0072] In the case of executing the outer cycle strategy, the nominal feed depth is iteratively compensated using the deformation displacements of the two positions until the iteration stop condition is reached and the displacement difference is obtained.

[0073] Furthermore, in one embodiment of the present invention, the common compensation module is specifically used for:

[0074] The displacement difference obtained by feedforward compensation and the displacement obtained by feedback compensation are used to jointly iteratively compensate the nominal feed depth of the tool until the preset convergence condition is reached, the machining process is stopped, and the given feed depth is obtained.

[0075] It should be noted that the aforementioned explanation of the embodiment of the countersink depth control method for the automated hole making process of a laminated component is also applicable to the countersink depth control device for the automated hole making process of a laminated component of this embodiment, and will not be repeated here.

[0076] According to the countersink depth control device for the automated hole making process of laminated components proposed in an embodiment of the present invention, a cutting force model and a workpiece deformation model are used to add a feedforward link in the countersink depth control to eliminate the system error caused by the difference between the workpiece deformation at the pressure ring position and the hole making position, and axial force detection is used to eliminate the influence of tool wear, thereby improving the countersink depth accuracy of the automated hole making process of laminated components.

[0077] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or N embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of the different embodiments or examples, without contradiction.

[0078] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In the description of the present invention, the meaning of "N" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0079] Any process or method description in a flowchart or otherwise described herein may be understood to represent a module, fragment or portion of code comprising one or N executable instructions for implementing the steps of a custom logical function or process, and the scope of the preferred embodiments of the present invention includes alternative implementations in which functions may not be performed in the order shown or discussed, including performing functions in a substantially simultaneous manner or in reverse order depending on the functions involved, which should be understood by technicians in the technical field to which the embodiments of the present invention belong.

Claims

1. A method for controlling the countersink depth in the automated hole making process of a laminated component, characterized in that: The following steps are involved: The cutting force model and workpiece deformation model of the countersinking process are constructed, wherein the workpiece deformation model is: ,in, represents the deformation caused by the compaction force, represents the deformation caused by the axial cutting force, is the hole making position, is the solution position of the deformation, and the cutting force model is: ,in, is the axial cutting force, For a given feed depth, Deformation of the workpiece; Determining a machining deformation compensation amount iteration strategy according to the cutting force model and the workpiece deformation model; The machining deformation compensation iterative strategy is executed to calculate the displacement difference between the press ring position and the hole center position during the machining process to construct a feedforward compensation, where the displacement difference is , and are respectively the calculated deformation displacements of the hole making position and the pressure ring position when the machining is completed; Based on the displacement sensor provided at the pressure ring position, the displacement of the workpiece at the pressure ring position during the machining process is collected to construct feedback compensation; The nominal feed depth of the tool is compensated by the feedforward compensation and the feedback compensation to obtain a given feed depth of the tool, wherein the compensated feed depth is , It is the feedback of the deformation displacement of the pressure ring obtained by real-time detection during the processing. is the nominal feed depth; The machining deformation compensation amount iteration strategy includes an inner layer loop strategy and an outer layer loop strategy, wherein: In the case of executing the inner layer circulation strategy, the coupling relationship between the cutting force and the workpiece deformation is determined according to the cutting force model and the workpiece deformation model, and the deformation displacements of two positions after the machining is completed are iteratively calculated according to the coupling relationship; When the outer layer circulation strategy is executed, the nominal feed depth is iteratively compensated using the deformation displacements of the two positions until an iteration stop condition is reached to obtain the displacement difference.

2. The method for controlling the countersink depth in the automatic hole making process of a laminated component according to claim 1, characterized in that: Before determining the iterative strategy of the machining deformation compensation amount, the method further includes: A force sensor is arranged in the tool to obtain the hole-making axial force during the machining process; Determining whether the wear degree of the tool exceeds a preset threshold value according to the hole-making axial force; If the preset threshold is not exceeded, determining an iterative strategy for machining deformation compensation using the cutting force model and the workpiece deformation model; If it exceeds the preset threshold, the cutting force model is corrected according to the hole-making axial force to obtain a new cutting force model, and the new cutting force model and the workpiece deformation model are used to determine the iterative strategy of the machining deformation compensation amount.

3. The method for controlling the countersink depth in the automatic hole making process of a laminated component according to claim 1, characterized in that: The method of jointly compensating the feed displacement of the tool by the feedforward compensation and the feedback compensation to obtain a given feed depth of the tool includes: The displacement difference obtained by the feedforward compensation and the displacement amount obtained by the feedback compensation are used to jointly iteratively compensate the nominal feed depth of the tool until a preset convergence condition is reached, the machining process is stopped, and the given feed depth is obtained.

4. A countersink depth control device for an automated hole making process of a laminated component, the countersink depth control device being used to execute the countersink depth control method according to any one of claims 1 to 3, characterized in that: include: Model building module, used to build cutting force model and workpiece deformation model of countersinking process; A determination module, used for determining a machining deformation compensation amount iteration strategy according to the cutting force model and the workpiece deformation model; A feedforward compensation building module is used to execute the machining deformation compensation amount iteration strategy to calculate the displacement difference between the press ring position and the hole making center position during the machining process to build feedforward compensation; A feedback compensation construction module, used to collect the displacement of the workpiece at the pressure ring position during the processing based on the displacement sensor set at the pressure ring position to construct feedback compensation; A common compensation module, used for jointly compensating the nominal feed depth of the tool through the feedforward compensation and the feedback compensation to obtain a given feed depth of the tool; The machining deformation compensation amount iteration strategy includes an inner layer loop strategy and an outer layer loop strategy, wherein: In the case of executing the inner layer circulation strategy, the coupling relationship between the cutting force and the workpiece deformation is determined according to the cutting force model and the workpiece deformation model, and the deformation displacements of two positions after the machining is completed are iteratively calculated according to the coupling relationship; When the outer layer circulation strategy is executed, the nominal feed depth is iteratively compensated using the deformation displacements of the two positions until an iteration stop condition is reached to obtain the displacement difference.

5. The device for controlling countersink depth in the automatic hole making process of a laminated component according to claim 4, characterized in that: Also includes: An updating module is used to set a force sensor in the tool to obtain the hole-making axial force during the machining process, and judge whether the wear of the tool exceeds a preset threshold value according to the hole-making axial force; if it does not exceed the preset threshold value, the cutting force model and the workpiece deformation model are used to determine the iterative strategy of the machining deformation compensation amount; if it exceeds the preset threshold value, the cutting force model is corrected according to the hole-making axial force to obtain a new cutting force model, and the new cutting force model and the workpiece deformation model are used to determine the iterative strategy of the machining deformation compensation amount.

6. The device for controlling countersink depth in the automatic hole making process of laminated components according to claim 4, characterized in that: The common compensation module is specifically used for: The displacement difference obtained by the feedforward compensation and the displacement amount obtained by the feedback compensation are used to jointly iteratively compensate the nominal feed depth of the tool until a preset convergence condition is reached, the machining process is stopped, and the given feed depth is obtained.

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