Design selecting and matching method and device for pressing mechanism of automatic drilling equipment for aircraft assembly

Abstract

The invention discloses a method and a device for designing, selecting and matching a pressing mechanism of automatic drilling equipment for aircraft assembly, and the method and the device are suitable for an aircraft assembly drilling process and serve as a guiding scheme for structural design of the automatic drilling equipment. Manufacturing indexes of different working condition differences of all hole sites are determined based on aircraft assembly hole manufacturing process correlation parameters; determining the size type of the pressing mechanism to be solved based on the structural characteristics of the pressing mechanism of the automatic hole making equipment; the curvature feature of the current hole making position is recognized, and a correlation model of the corresponding pressing mechanism size design is called; and threshold calibration is carried out based on the manufacturing index of the current hole manufacturing position, and pressing mechanisms of different sizes are preferably selected and matched. According to the invention, the characteristics of the to-be-processed product and the structural characteristics of the pressing mechanism of the automatic hole-making equipment can be interactively associated, and the accuracy and flexibility of selecting and matching the tail end mechanism of the automatic hole-making equipment can be improved.

Description

Technical Field

[0001] The present invention relates to the field of, but is not limited to, automated hole-making technology, and in particular to a design and selection method and device for a clamping mechanism of automated hole-making equipment for aircraft assembly. Background Art

[0002] During aircraft assembly, drilling is a heavy workload. The quality of drilling significantly impacts the integrity of the aircraft structure, while drilling efficiency significantly impacts the assembly cycle. To meet the drilling quality requirements for various structural conditions, the development of drilling equipment is becoming increasingly challenging.

[0003] Typical automatic hole-making equipment can be roughly divided into six structures: automatic bracket-type hole-making system, gantry-type automatic hole-making system, column-type machine tool automatic drilling and riveting system, robot-type automatic hole-making system, flexible guide rail automatic hole-making system, and autonomous crawling robot-type hole-making system. Among them, the module directly related to the hole-making quality is the hole-making end effector. The end structure developed based on the product working conditions must meet the requirements of hole-making position, verticality, countersink depth, hole-making surface quality, etc. The pressure foot mechanism in the end effector is an execution unit that is directly bonded to the product. The rationality of its structural design is directly related to the hole-making result. In particular, the countersink accuracy, during the process of the clamping mechanism applying the clamping force to the product, the mechanical interference between itself and the product structure becomes one of the factors affecting the countersink accuracy.

[0004] Therefore, in order to improve the rationality of the structural design of hole-making equipment, it is necessary to develop a key component design scheme based on product manufacturing indicators, improve the flexibility and adaptability of the hole-making equipment development process, and further ensure the hole-making accuracy. Summary of the Invention

[0005] In order to solve the above problems, the present invention provides a design and selection method and device for the clamping mechanism of automatic hole-making equipment for aircraft assembly, so as to solve the problem in the prior art that the automatic hole-making equipment structure has low adaptability to the hole-making working conditions, resulting in large differences in hole-making results.

[0006] A first aspect of the present invention provides a method for designing and selecting a clamping mechanism of an automatic hole-making device for aircraft assembly, comprising:

[0007] S1, for any hole-making position, obtain the process-related parameters and manufacturing index thresholds of the hole-making position;

[0008] S2, identifying the curvature characteristics of the hole-making position and calling the corresponding associated model for the size design of the clamping mechanism;

[0009] S3, adopts process correlation parameters, manufacturing index thresholds and correlation models to realize the design and selection of the clamping mechanism.

[0010] Optionally, the process-related parameters include: target hole diameter d, target countersink diameter D, target countersink depth H, target countersink half angle θ, and target hole verticality tolerance α.

[0011] Optionally, the curvature characteristics of the hole-making position include: a plane structure, a positive curvature structure, and a negative curvature structure;

[0012] The curvature of the planar structure limK→0, and the curvature radius limR→∞;

[0013] The curvature K of the positive curvature structure is greater than 0, that is, the structure is convex toward the outside of the product with the plane as the reference;

[0014] The curvature K of the negative curvature structure is less than 0, that is, the structure is concave toward the inside of the product with the plane as the reference.

[0015] Optionally, identifying the curvature characteristics of the hole-making position and calling the associated model for the corresponding clamping mechanism size design include:

[0016] When limK→0, the association model is

[0017] When K>0, When , the association model is

[0018]

[0019] When K>0, When , the association model is

[0020]

[0021] When K<0, the association model is

[0022]

[0023] in, D′=2H′tanθ+d; D1 is the maximum nominal dimension of the outer edge of the clamping nose of the clamping mechanism, and D2 is the maximum nominal dimension of the inner edge of the clamping nose of the clamping mechanism; s is the wall thickness of the clamping nose, s=D1-D2; h is the depth of the countersink in the aircraft assembly hole.

[0024] Optionally, process-related parameters, manufacturing index thresholds, and related models are used to implement the design and selection of the clamping mechanism, including:

[0025] When limK→0, the formula Realize the design and selection of the clamping mechanism;

[0026] When K>0, When using the formula

[0027] , realize the design and selection of the clamping mechanism;

[0028] When K>0, When using the formula

[0029] Realize the design and selection of the clamping mechanism;

[0030] When K<0, use the formula

[0031] Realize the design and selection of the clamping mechanism;

[0032] Wherein, Δh is the manufacturing indicator threshold of the countersink depth.

[0033] Optionally, the structural features of the pressing mechanism include: an annular flat end face structure of equal thickness, an annular flat end face structure of unequal thickness, an annular arc end face structure, a polygonal flat end face structure, and a semi-annular flat end face structure.

[0034] A second aspect of the present invention provides a design and selection device for a clamping mechanism of an automatic hole-making device for aircraft assembly, which is used to execute the method described in any one of the first aspects.

[0035] A third aspect of the present invention provides a storage medium, comprising: a memory and a processor;

[0036] The memory is configured to store executable instructions;

[0037] The processor is configured to implement the method as described in any one of the first aspects when executing the executable instructions stored in the memory.

[0038] Beneficial Effects of the Invention: In the field of automated hole-making in aircraft assembly, to improve the adaptability of customized automated hole-making equipment and enhance product hole-making precision, this invention proposes a design and selection method for the clamping mechanism of automated hole-making equipment in aircraft assembly. Based on product structural characteristics and the independent manufacturing index requirements for each hole-making position, this method constructs a correlation model between the design dimensions of the clamping mechanism and the hole-making operating conditions. This ensures that the hole-making equipment structure meets the operating conditions of each hole position, providing theoretical guidance for the targeted development of non-standard equipment. This represents a design method for high-precision manufacturing mechanisms based on product requirements. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] Figure 1 This is a flow chart of the design and selection method for a clamping mechanism of an automatic hole-making equipment for aircraft assembly;

[0040] Figure 2 This is a three-dimensional structural diagram of the end effector of the automatic hole-making equipment;

[0041] Figure 3This is a schematic diagram showing the influence of the position error of the clamping mechanism on the manufacturing accuracy of the countersink depth during the product hole making process;

[0042] Figure 4(a) shows the design dimensions of the pressing mechanism of the automatic hole-making equipment when the hole-making object is a flat plate structure;

[0043] Figure 4(b) shows the design dimensioning of the clamping mechanism of the automatic hole-making equipment when the hole-making object is a convex curvature structure;

[0044] Figure 4(c) shows the design dimensioning of the clamping mechanism of the automatic hole-making equipment when the hole-making object is a concave curvature structure;

[0045] Figure 5(a) is a data matrix 1 of the design dimensions of the compressed nose piece;

[0046] Figure 5(b) is the data matrix 2 for the design dimensions of the compressed nose piece;

[0047] Figure 5(c) shows the data matrix 3 of the design dimensions of the compressed nose piece.

[0048] Description of reference numerals:

[0049] 1. Aircraft assembly hole-making system end effector; 2. Clamping mechanism; 3. Hole-making unit; 4. Hole-making tool; 5. Clamping nose piece; 6. Normal laser rangefinder. DETAILED DESCRIPTION

[0050] To make the purpose, technical solutions, and advantages of the embodiments of the present invention more clear, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making any creative work are within the scope of protection of the present invention.

[0051] The features and illustrative embodiments of various aspects of the present invention will be described in detail below. In the detailed description below, many specific details are proposed in order to provide a comprehensive understanding of the present invention. However, it will be apparent to those skilled in the art that the present invention can be implemented without the need for some of these specific details. The following description of the embodiments is merely intended to provide a better understanding of the present invention by illustrating examples of the present invention. The present invention is in no way limited to any specific arrangement and method proposed below, but rather encompasses any improvements, replacements, and modifications to structures, methods, and devices without departing from the spirit of the present invention. In the accompanying drawings and the following description, well-known structures and techniques are not shown to avoid unnecessary ambiguity in the present invention.

[0052] In the description of the present invention, it should be noted that the directions or positional relationships indicated by terms such as "center," "up," "down," "left," "right," "vertical," "horizontal," "inside," and "outside" are based on the directions or positional relationships described in the accompanying drawings and are intended only to facilitate and simplify the description of the present invention and should not be construed as limiting the present invention. Furthermore, the use of ordinal numbers (e.g., "first and second," etc.) is intended to distinguish between objects and is not limited to this order, and should not be construed as indicating or implying relative importance.

[0053] In the description of the present invention, it should be noted that, unless otherwise specified or limited, the terms "mounted," "connected," and "connected" should be understood broadly, and may refer to direct connection or indirect connection through an intermediary. Those skilled in the art will understand the specific meanings of these terms in the present invention.

[0054] It should be noted that, in the absence of conflict, the embodiments of the present invention and the features in the embodiments can be combined with each other, and the embodiments can refer to and quote each other. The present invention will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0055] The present invention will be described in further detail below with reference to the embodiments and drawings, but the embodiments of the present invention are not limited thereto.

[0056] The present invention provides a design and selection method for a pressing mechanism of an automatic hole-making device for aircraft assembly, comprising:

[0057] Step 1: Based on the aircraft assembly hole making process related parameters, the manufacturing indicators of each hole position under different working conditions are determined;

[0058] Step 2: Based on the structural characteristics of the clamping mechanism of the automatic hole-making equipment, the size type of the clamping mechanism to be solved is determined;

[0059] Step 3: Identify the curvature characteristics of the current hole-making position and call the associated model for the corresponding clamping mechanism size design;

[0060] Step 4: perform threshold calibration based on the manufacturing indicators of the current hole-making position, and select the best clamping mechanisms of different sizes.

[0061] Exemplarily, the aircraft assembly hole making process associated parameters in step 1 include:

[0062] Target hole diameter d, target countersink diameter D, target countersink depth H, target countersink half angle θ, target hole verticality tolerance α; each manufacturing target should meet the corresponding manufacturing index requirements;

[0063] Exemplarily, the structural features of the pressing mechanism in step 2 include but are not limited to an annular flat end surface structure of equal thickness, an annular flat end surface structure of unequal thickness, an annular arc end surface structure, a polygonal flat end surface structure, and a semi-annular flat end surface structure;

[0064] Exemplarily, the characteristic dimension types of the pressing mechanism in step 2 include:

[0065] The maximum nominal dimension of the outer edge of the pressing nose piece is D1, and the maximum nominal dimension of the inner edge of the pressing nose piece is D2;

[0066] The dimensions must satisfy D2>D1; the thickness of the nose piece should be s=D1-D2;

[0067] Illustratively, the local curvature characteristics of the hole-making position in step 3 include but are not limited to a planar structure, a positive curvature structure, and a negative curvature structure.

[0068] The curvature of the planar structure limK→0, and the curvature radius limR→∞;

[0069] The curvature K of the positive curvature structure is greater than 0, that is, the structure is convex toward the outside of the product with the plane as the reference;

[0070] The curvature K of the negative curvature structure is less than 0, that is, the structure is concave toward the inside of the product with the plane as the reference;

[0071] Exemplarily, the association model for the design of the dimensions of the pressing mechanism in step 3 includes the following sub-steps:

[0072] Step 31, when limK→0, the correlation model of the aircraft assembly hole countersink depth h is

[0073] Step 32, when K>0, When the depth h of the countersink in aircraft assembly is

[0074]

[0075] in, D′=2H′tanθ+d;

[0076] Step 33, when K>0, When the depth h of the countersink in aircraft assembly is

[0077]

[0078] in, D′=2H′tanθ+d;

[0079] Step 34: When K < 0, the correlation model of the countersink depth h in aircraft assembly is

[0080]

[0081] in, D′=2H′tanθ+d;

[0082] For example, the manufacturing indicators in step 4 include but are not limited to dimensional accuracy: hole diameter, countersink diameter, countersink depth; shape accuracy: hole coaxiality, hole verticality;

[0083] Exemplarily, the step 4 of calibrating the design dimension threshold of the clamping mechanism based on the manufacturing index includes the following sub-steps:

[0084] Step 41 , selecting the structural dimensions of the pressing nose piece according to the manufacturing index Δh of the countersink depth, that is, satisfying the target countersink depth H-countersink depth h≤Δh;

[0085] Step 42, when limK→0, the dimensions of the nose piece must satisfy

[0086]

[0087] Step 42, when K>0, When the nose piece is pressed, the structural dimensions must meet

[0088]

[0089] Step 43, when K>0, When the nose piece is pressed, the structural dimensions must meet

[0090]

[0091] Step 44: When K<0, the dimensions of the nose piece must meet

[0092]

[0093] Figure 1 This is a flow chart of a method for designing and selecting a clamping mechanism for automated hole-drilling equipment in aircraft assembly, provided by an embodiment of the present disclosure. Considering a product with multiple hole-drilling locations on its exterior surface as the object to be drilled, the present invention identifies the manufacturing specifications for each hole-drilling location, invokes an associated model for the dimensional constraints of the corresponding clamping nose piece based on the product's characteristics, and selects a structural design based on the model analysis results to meet the differentiated operating requirements of each hole-drilling location.

[0094] Figure 2 This is a three-dimensional structural diagram of the end effector of the automatic hole-making equipment. The end effector 1 of the aircraft assembly hole-making system is integrated with multiple mechanisms such as the clamping mechanism 2, the hole-making unit 3, the clamping nose piece 5, and the normal laser rangefinder 6. Among them, the main actuator of the hole-making unit is the hole-making tool 4.

[0095] Figure 3 This diagram shows the impact of the clamping mechanism's posture error on the precision of the countersink depth during the hole-making process. Since the tool feed rate during the hole-making process is closed-loop controlled with the nose end face as the coordinate zero, the distance the tool tip extends from the nose end face remains consistent for holes of the same size. However, due to the randomness of the normal posture error within the adjustment threshold for each hole position, the cutting depth after the tool contacts the material varies, ultimately resulting in low consistency in the countersink depth.

[0096] Figures 4(a), 4(b), and 4(c) illustrate the structural types and design dimensions of the clamping mechanism for automated hole-making equipment. Modeling is performed on the area where the clamping nose fits the product, characterizing the constraint relationship between the clamping nose dimensions and the countersink depth. Figure 4(a) illustrates a flat plate, Figure 4(b) a convex curvature, and Figure 4(c) a concave curvature.

[0097] For example, during the hole-making process, with a constant tool feed rate, the distance the tool tip extends from the nose end face is, in principle, a constant value. Under this premise, a profile analysis of three product types, flat plates and positive and negative curved plates, was performed. The analysis assumes that the product and pressure foot structure are rigid bodies. The inner diameter of the nose is D2; the outer diameter is D1; ​​the pocket diameter is D; the hole diameter is d; the pocket depth is H; the half-angle of the countersink is θ; and the normal deviation angle after the clamping mechanism is clamped is α, where α is the normal error tolerance.

[0098] The relationship between the pit depth and the pit diameter is:

[0099]

[0100] Modeling is performed based on the geometric relationship in Figure 4(a), that is, the curvature K of the hole-making object is infinitely close to 0. At this time, after the normal correction has an angle deviation, the pocket depth h is:

[0101]

[0102] a) Fixed pressure foot nose piece size, socket depth change rules

[0103] Taking the outer diameter D1 of the pressure foot nose piece as 30 mm as an example, the normal deviation angle was adjusted to measure the socket depth data, as shown in Table 1. For a given pressure foot nose piece size and normal deviation angle, the larger the hole diameter, the greater the socket depth deviation.

[0104] Table 1 Correspondence between normal deviation angle and pocket depth

[0105]

[0106] b) Correlation between the size of the pressure foot nose piece and the change of the depth of the socket by the hole size

[0107] Table 2 Correspondence between pressure foot nose piece size and socket depth

[0108]

[0109] According to the data distribution law in Table 2, we can get:

[0110] 1) Under the premise of keeping the hole diameter consistent, as the diameter of the pressure nose increases, the countersink depth becomes shallower; and as the normal deflection angle increases, the countersink depth becomes shallower;

[0111] 2) Under the premise of maintaining the same ratio of the nose diameter to the countersink diameter, the deviation of the socket depth increases with the increase of the hole diameter. For example, when the ratio of the nose diameter to the countersink diameter is 2, the maximum socket depth deviation of the Φ5 hole is 0.06mm, while the maximum socket depth deviation of the Φ14 hole is 0.18mm.

[0112] 3) If the manufacturing accuracy of all hole sizes is required to be the same with the same socket depth index, the ratio of the pressure nose to the socket diameter should be smaller as the hole diameter increases.

[0113] Modeling is performed based on the geometric relationship in Figure 4(b), where the curvature K of the hole-making object is greater than 0, the product is a convex curvature structure, and the arc length formula is known to be:

[0114]

[0115] β is the central angle of the circle at this arc length.

[0116] Define the wall thickness of the pressure nose ring as s. According to the geometric relationship after normal deflection, when the pressure nose rotates and the contact point with the product transitions from the inner diameter of the ring to the outer diameter, s and the product curvature radius R must meet the following requirements:

[0117]

[0118] Where α is the deflection angle of the pressure foot, typically <= 0.3°; R is the radius of curvature of the product. If the wall thickness s of the pressure foot nose piece meets the above relationship, the contact point after pressing with the product will be the inner diameter of the nose piece ring; if not, the contact point will be the outer ring of the nose piece.

[0119] For example, when the wall thickness of the nose ring is s = 5mm and the maximum normal deflection angle α = 0.3°, and the curvature radius R of the product is greater than 954.92mm, the pressing contact point is the inner diameter of the nose ring. Conversely, if the curvature radius R is less than 954.92mm, the pressing contact point is the outer diameter of the nose ring.

[0120] When the contact point is the inner diameter of the nose ring, according to the geometric relationship in the figure above, after the normal correction causes an angular deviation, the pocket depth h is:

[0121]

[0122] Among them, H is the depth of the nest, D′=2H′tanθ+d.

[0123] When the contact point is the outer diameter of the nose ring, according to the geometric relationship in the figure above, after the normal correction causes an angular deviation, the pocket depth h is:

[0124]

[0125] Table 3 Correspondence between curvature change and fossa depth when the nose size is 35mm

[0126]

[0127] Comparing Table 3 with Table 1, we can get:

[0128] 1) Under the premise of the same hole diameter, the groove depth of the curved plate is smaller than that of the flat plate;

[0129] 2) To reduce the socket depth deviation, the nose piece wall thickness should be appropriately increased in the low curvature area;

[0130] 3) Under the same normal deviation angle, when the curvature radius increases from 5000 to 20000, the fluctuation of the dimple depth is very small, and it increases slightly.

[0131] 4) When the curvature radius is within [5000, 20000], the curvature change has little effect on the dimple depth. In short, when the curvature change is within this range, the main factors affecting the dimple depth of the curved plate and the flat plate remain consistent, and the dimple depth change mainly depends on the normal deflection angle and the nose size.

[0132] Modeling is performed based on the geometric relationship in Figure 4(c), where the curvature of the hole-making object K < 0 and the product has a concave curvature structure. It is known that when the product curvature change is negative, the contact point of the pressure foot nose piece is the outer diameter of the ring. Based on the geometric relationship in the figure above, after the normal correction causes an angular deviation, the pocket depth h is:

[0133]

[0134] Table 4 Correspondence between curvature change and fossa depth when the nose size is 35mm

[0135]

[0136] Comparing Table 3 and Table 4, it can be seen that the influence of positive and negative curvature changes on the dimple depth remains consistent; the dimple depth change rules are roughly the same as the flat plate rules.

[0137] It's understood that the "?h" in Figures 4(a), 4(b), and 4(c) indicates a parameter requiring a solution. The design principles of the pressure foot structure in this example are highly correlated with h, so it's necessary to first define the limits of h before deriving the dimensions of D1 and D2 within the pressure foot structure. Therefore, the "?" preceding h in the figures serves as a clear indicator of the parameter requiring a solution.

[0138] Figures 5(a), 5(b), and 5(c) are data matrices for the design dimensions of the clamping nose. Based on the calculation process described above, some conventional clamping nose dimensions that meet specific countersink precision manufacturing specifications are listed. " / " in the figure indicates that the design dimension is not constrained and can take any value. The units of the countersink depth accuracy specification Δh in the figure are millimeters (mm), the hole perpendicularity tolerance α is in degrees (°), and the maximum nominal dimensions of the outer edge of the clamping nose, D1, and the maximum nominal dimensions of the inner edge, D2, are in millimeters (mm).

[0139] The foregoing description shows and describes preferred embodiments of the present invention. As previously mentioned, it should be understood that the present invention is not limited to the form disclosed herein and should not be construed as excluding other embodiments. Instead, the present invention can be used in various other combinations, modifications, and environments and can be modified within the scope of the inventive concept described herein by the teachings above or by techniques or knowledge in the relevant art. Modifications and variations made by those skilled in the art without departing from the spirit and scope of the present invention are intended to be within the scope of the appended claims.

Claims

1. A design and selection method for a clamping mechanism of an automatic hole-making equipment for aircraft assembly, characterized in that: include: S1, for any hole-making position, obtain the process-related parameters and manufacturing index thresholds of the hole-making position; S2, identifying the curvature characteristics of the hole-making position and calling the corresponding associated model for the size design of the clamping mechanism; S3, adopts process correlation parameters, manufacturing index thresholds and correlation models to realize the design and selection of the clamping mechanism.

2. The design and selection method of a clamping mechanism for an automatic hole-making device for aircraft assembly according to claim 1, characterized in that: The process-related parameters include: target hole diameter d, target countersink diameter D, target countersink depth H, target countersink half angle θ, and target hole verticality tolerance α.

3. The design and selection method of a clamping mechanism for an automatic hole-making device for aircraft assembly according to claim 2, characterized in that: The curvature characteristics of the hole making position include: plane structure, positive curvature structure, and negative curvature structure; The curvature of the planar structure limK→0, and the curvature radius limR→∞; The curvature K of the positive curvature structure is greater than 0, that is, the structure is convex toward the outside of the product with the plane as the reference; The curvature K of the negative curvature structure is less than 0, that is, the structure is concave toward the inside of the product with the plane as the reference.

4. The design and selection method of a clamping mechanism for an automatic hole-making device for aircraft assembly according to claim 3, characterized in that: Identifying the curvature characteristics of the hole-making position and calling the corresponding associated models for clamping mechanism size design include: When limK→0, the association model is When K>0, When , the association model is When K>0, When , the association model is When K<0, the association model is in, D′=2H′tanθ+d; D1 is the maximum nominal dimension of the outer edge of the clamping nose of the clamping mechanism, and D2 is the maximum nominal dimension of the inner edge of the clamping nose of the clamping mechanism; s is the wall thickness of the clamping nose, s=D1-D2; h is the depth of the countersink in the aircraft assembly hole.

5. The design and selection method of the clamping mechanism of the automatic hole-making equipment for aircraft assembly according to claim 4 is characterized in that: Adopting process-related parameters, manufacturing index thresholds and related models, the design and selection of the clamping mechanism are realized, including: When limK→0, the formula Realize the design and selection of the clamping mechanism; When K>0, When using the formula Realize the design and selection of the clamping mechanism; When K>0, When using the formula Realize the design and selection of the clamping mechanism; When K<0, use the formula Realize the design and selection of the clamping mechanism; Wherein, Δh is the manufacturing indicator threshold of the countersink depth.

6. The design and selection method of a clamping mechanism for an automatic hole-making device for aircraft assembly according to claim 1, characterized in that: The structural features of the clamping mechanism include: an annular flat end face structure with equal thickness, an annular flat end face structure with non-equal thickness, an annular arc end face structure, a polygonal flat end face structure, and a semi-annular flat end face structure.

7. A design and selection device for the clamping mechanism of an automatic hole-making equipment for aircraft assembly, characterized in that: Used to perform the method according to any one of claims 1 to 6.

8. A computer-readable storage medium, characterized in that include: memory and processor; The memory is configured to store executable instructions; The processor is configured to implement the method according to any one of claims 1 to 6 when executing the executable instructions stored in the memory.

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