Flexible electromagnetic progressive shape correction method for continuous large-profile peak height defect of skin

Abstract

The invention discloses a skin continuous large-profile peak height defect flexible electromagnetic progressive shape correction method, which comprises the following steps: establishing an electromagnetic shape correction skin large-profile peak height deformation prediction model, and determining the influence of material flow on deformation of adjacent areas needing shape correction in the shape correction process of a continuous large-profile peak height skin sheet metal part; and meanwhile, by restraining the influence on deformation of the adjacent protruding area after electromagnetic shaping of the protruding area, the electromagnetic shaping frequency and the single electromagnetic shaping force are optimized, automatic shaping of the continuous large-contour peak-height skin sheet metal part is achieved, and the automatic shaping precision of the continuous large-contour peak-height skin sheet metal part is improved. The efficiency is improved, and the labor cost is reduced.

Description

Technical Field

[0001] The present invention belongs to the technical field of electromagnetic sheet metal forming, and particularly relates to a flexible electromagnetic progressive calibration method for skin continuous large-profile peak height defects. Background Art

[0002] Applying electromagnetic force to the skin under manual operation conditions can cause the skin to deform through the electromagnetic force, thereby realizing the calibration of the skin continuous large-profile peak height defects. However, in the existing electromagnetic calibration process of the skin, it is impossible to predict the deformation amount and the attitude after electromagnetic deformation of the skin under the influence of different electromagnetic forces. Therefore, it is only possible to rely on manual operation experience to apply electromagnetic force to the skin. And after each application of electromagnetic force, it is necessary to measure the attitude of the skin again after deformation, and then estimate the electromagnetic force parameters to be applied to the skin next time based on the measurement results. This leads to the existing electromagnetic calibration of the skin being highly dependent on the experience of the operator, and it is difficult to predict whether the electromagnetic force applied during the electromagnetic calibration process of the skin is appropriate and whether the deformation amount of the skin meets the expectations. Therefore, it greatly affects the processing efficiency of the skin calibration. At the same time, due to inappropriate electromagnetic force parameters, problems such as skin cracking, wrinkling, and uneven thickness may also occur.

[0003] Therefore, in view of the above problems existing in the electromagnetic calibration of the existing skin continuous large-profile peak height defect area, the present invention discloses a flexible electromagnetic progressive calibration method for skin continuous large-profile peak height defects. Summary of the Invention

[0004] The present invention discloses a flexible electromagnetic progressive calibration method for skin continuous large-profile peak height defects, which can accurately determine the deformation amount, pose, and influence relationship of adjacent deformation regions after the skin is stressed during the electromagnetic calibration process of the skin, and optimize the optimal electromagnetic calibration force and processing method to meet the requirements of high-quality and high-efficiency forming, and reduce the influence of wrinkles, uneven thickness, etc. on the forming quality after calibration.

[0005] The present invention is achieved through the following technical solutions: A flexible electromagnetic progressive shaping method for continuous large-profile peak height defects of skin, establishing a deformation prediction model for electromagnetic shaping of large-profile peak height defects of skin. The deformation prediction model is used to characterize the influence degree of material flow occurring during the electromagnetic shaping process of continuous large-profile peak height defects of skin sheet metal parts on the deformation of adjacent shaping areas; based on the deformation prediction model, solving the skin surface function corresponding to different magnitudes of electromagnetic forces acting on the convex areas of the skin, establishing a die surface function, solving the shaping points of the skin in different convex areas based on the skin surface function and the die surface function, applying electromagnetic shaping force at the shaping points, and predicting the optimal influence degree of the electromagnetic shaping force applied at the current shaping point on the deformation of adjacent shaping areas through the deformation prediction model. Input the electromagnetic shaping force corresponding to the optimal influence degree into the deformation prediction model for iterative optimization until the distance between the skin and the die is equal to the thickness of the skin, and output the optimal electromagnetic shaping force for each shaping area.

[0006] To better implement the present invention, further, it specifically includes the following steps: Step 1: Establish several skin feature points on the skin, and based on the electromagnetic shaping parameters at the skin feature points, establish the force deformation amount and deformation amount constraint conditions of the skin feature points to obtain a deformation prediction model; Step 2: Input different electromagnetic shaping parameters into the deformation prediction model, and fit to obtain the skin surface function corresponding to different magnitudes of electromagnetic forces acting on the convex areas of the skin; Step 3: Establish several die feature points on the skin die, and fit to obtain a die surface function based on the die feature points; Step 4: Solve the shaping points of the skin in different convex areas based on the skin surface function and the die surface function. The shaping points include the contact points between the skin and the die and the highest points of the convex areas of the skin, and establish a shaping angle for any two adjacent convex areas based on the contact points and the highest points; Step 5: Apply electromagnetic shaping force at the highest point of any convex area, and predict, through the deformation prediction model, the electromagnetic shaping force corresponding to the critical value of the shaping angle of the deformation of its adjacent convex area when the electromagnetic shaping force is applied at the current highest point as one of the shaping parameters and input it into the deformation prediction model; Step 6: Alternately repeat steps 2 - 5 in different adjacent convex areas iteratively until the distance between the highest point of the convex area and the die is equal to the thickness of the skin, and output the electromagnetic shaping force applied at the convex area at this time as the optimal electromagnetic shaping force.

[0007] To better implement the present invention, further, establishing the deformation prediction model includes the following steps: Step A1: Based on the global coordinate system, establish S skin feature points on the skin, and establish a local coordinate system of the skin relative to the global coordinate system in the cutting direction of any skin feature point; Step A2: Establish a function of the force relationship between two adjacent skin feature points; Step A3: Establish a function of the deformation relationship between the electromagnetic calibration parameters and the force-induced deformation at any skin feature point; Step A4: Establish a function of the deformation quantity constraint condition for the skin feature point; Step A5: Combine the force relationship function, the deformation relationship function, and the deformation quantity constraint condition function to obtain the deformation prediction model.

[0008] To better implement the present invention, further, the force relationship function in Step A2 is as follows: ; Where: represents the deflection angle of the local coordinate system of the skin relative to the global coordinate system; represents the deformation in the X , , , , , , , ,

[0009] , t ,

[0008] , , t , , , , , , , , , , t , ,

[0010] , t , , , , , , , direction of the skin; represents the deformation in the Y t direction of the skin; represents the radial force on the s-th skin feature point; represents the tangential force on the s-th skin feature point; represents the bending moment on the s-th skin feature point; represents the radial force on the first skin feature point; represents the tangential force on the first skin feature point; represents the bending moment on the first skin feature point; k represents the curvature of the skin.

[0009] To better implement the present invention, further, the deformation relationship function in Step A3 is as follows: Where: represents the radial force on the t-th skin feature point, t ≤ s; represents the tangential force on the t-th skin feature point; represents the bending moment on the t-th skin feature point; represents the deformation in the X t direction of the skin; represents the deformation in the Y t direction of the skin; represents the angle between the tangent of any skin feature point and the tangential force; k represents the curvature of the skin.

[0010] To better implement the present invention, further, the deformation quantity constraint condition function in Step A4 is as follows: ; Where: S represents s skin feature points; t represents the t-th skin feature point, t ≤ s; represents the deformation of the skin along the X-axis of the global coordinate system t direction; represents the deformation of the skin along the Y-axis of the global coordinate system t direction; represents the deformation of the tangent direction at the t-th skin feature point; represents the deformation of the normal direction at the t-th skin feature point; k represents the curvature of the skin; represents the angle between the tangent direction of any skin feature point and the horizontal direction; represents the deflection angle of the local coordinate system of the skin relative to the global coordinate system; k represents the curvature of the skin.

[0011] To better implement the present invention, further, in step 4, the formula for solving the contact points between the skin and the mold is as follows: F s (x, y) = F m (x, y); Based on the formula of the contact points, at least three contact points between the skin and the mold are calculated: , , ; Where: F s (x, y) represents the skin surface function; F m (x, y) represents the mold surface function; represents the coordinates of contact point A; represents the coordinates of contact point C; represents the coordinates of contact point E.

[0012] To better implement the present invention, further, in step 4, the formula for solving the highest point between the skin and the mold is as follows: ; ; Based on the formula of the highest point, the highest points of any two adjacent raised areas between the skin and the mold are calculated as: , ; Where: Fs(x, y) represents the skin surface function; Fm(x, y) represents the mold surface function; represents the coordinates of the highest point B of the first raised area; represents the coordinates of the highest point D of the second raised area.

[0013] To better implement the present invention, further, the calculation formula for the sizing angle of any two adjacent said convex regions is as follows: ; ; Where: represents the sizing angle of the first convex region; represents the sizing angle of the second convex region; represents the abscissa of the contact point A; represents the ordinate of the contact point A; represents the abscissa of the highest point B; represents the ordinate of the highest point B; represents the abscissa of the contact point C; represents the ordinate of the contact point C; represents the abscissa of the highest point D; represents the ordinate of the highest point D; represents the abscissa of the contact point E; represents the ordinate of the contact point E.

[0014] To better implement the present invention, further, the critical value of the sizing angle is 85°.

[0015] Compared with the prior art, the present invention has the following advantages and beneficial effects: The present invention constructs a deformation prediction model for the peak height of the electromagnetic sizing skin large contour, clarifies the influence of the material flow occurring during the sizing process of the continuous large contour peak height skin sheet metal part on the deformation of the adjacent areas to be sized, and thus avoids the electromagnetic forming force being too large resulting in the electromagnetic sizing critical angle of the adjacent areas to be sized exceeding the tolerance. At the same time, the present invention optimizes the number of electromagnetic sizing times and the single electromagnetic sizing force by restricting the influence of the electromagnetic sizing of the convex region on the deformation of the adjacent convex regions, realizes the automatic sizing of the continuous large contour peak height skin sheet metal part, improves the efficiency, and reduces the labor cost. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 is a schematic flow chart of the method of the present invention; Figure 2 is a schematic diagram of applying an electromagnetic sizing force to the first convex region; Figure 3 is a schematic diagram of applying an electromagnetic sizing force to the second convex region; Figure 4 is a schematic diagram when the sizing angle of the first convex region reaches the critical value; Figure 5 is a schematic diagram when the sizing of the first convex region is completed; Figure 6Schematic diagram of the calibration completion for the first and second convex regions; Figure 7 Schematic diagram of the local coordinate system of the skin; Figure 8 Schematic diagram of the calibration parameters at the characteristic points of the skin. Detailed implementation manner

[0017] Example 1: A flexible electromagnetic progressive calibration method for the peak height defect of the continuous large contour of the skin in this embodiment establishes a deformation prediction model for the peak height defect of the large contour of the electromagnetic calibrated skin. The deformation prediction model is used to characterize the influence degree of the material flow occurring during the electromagnetic calibration process of the continuous large contour peak height defect of the skin sheet metal part on the deformation of the adjacent calibration regions; based on the deformation prediction model, the skin surface function corresponding to different sizes of electromagnetic forces acting on the convex regions of the skin is solved, a die surface function is established, and the calibration points of the skin in different convex regions are solved based on the skin surface function and the die surface function. An electromagnetic calibration force is applied at the calibration points, and the optimal influence degree of the electromagnetic calibration force applied at the current calibration point on the deformation of the adjacent calibration regions is predicted through the deformation prediction model. The electromagnetic calibration force corresponding to the optimal influence degree is input into the deformation prediction model for iterative optimization until the distance between the skin and the die is equal to the thickness of the skin, and the optimal electromagnetic calibration force of each calibration region is output.

[0018] As Figure 1 shown, it specifically includes the following steps: Step 1: Establish a number of skin characteristic points on the skin. Based on the electromagnetic calibration parameters at the skin characteristic points, establish the force deformation amount and deformation amount constraint conditions of the skin characteristic points to obtain a deformation prediction model; Step 2: Input different electromagnetic calibration parameters into the deformation prediction model, and fit to obtain the skin surface function corresponding to different sizes of electromagnetic forces acting on the convex regions of the skin; Step 3: Establish a number of die characteristic points on the skin die, and fit to obtain a die surface function based on the die characteristic points; Step 4: Solve the calibration points of the skin in different convex regions based on the skin surface function and the die surface function. The calibration points include the contact points between the skin and the die and the highest points of the convex regions of the skin. Based on the contact points and the highest points, establish the calibration angles of any two adjacent convex regions; Step 5: Apply an electromagnetic calibration force at the highest point of any convex region, and predict through the deformation prediction model the electromagnetic calibration force corresponding to the critical value of the calibration angle of the deformation of the adjacent convex region when the electromagnetic calibration force is applied at the current highest point as one of the calibration parameters and input it into the deformation prediction model; Step 6: Alternately repeat steps 2 - 5 in different adjacent convex regions for iteration. As Figures 2 - 6As shown, until the distance between the highest point of the raised area and the mold is equal to the thickness of the skin, the electromagnetic shaping force applied by the raised area at this time is output as the optimal electromagnetic shaping force.

[0019] Embodiment 2: This embodiment is further optimized on the basis of the above-mentioned embodiment 1, and establishing a deformation prediction model includes the following steps: Step A1: establishing S skin feature points on the skin based on the global coordinate system, and establishing a skin local coordinate system relative to the global coordinate system in the cutting direction of any skin feature point; Step A2, establishing a force relationship function between two adjacent skin feature points; Step A3, establishing a deformation relationship function between the electromagnetic correction parameter and the force deformation at any skin feature point; Step A4, establishing a deformation constraint function of skin feature points; Step A5: The deformation prediction model can be obtained by combining the force relationship function, the deformation relationship function and the deformation constraint condition function.

[0020] The force relationship function in step A2 is as follows: ; in: Indicates the deflection angle of the skin local coordinate system relative to the global coordinate system; Indicates the X coordinate of the skin along the global coordinate system t Directional deformation; Represents the Y coordinate of the skin along the global coordinate system t Directional deformation; Indicates the radial force on the s-th skin feature point; Indicates the tangential force on the s-th skin feature point; represents the bending moment of the s-th skin feature point; Indicates the radial force on the first skin feature point; Indicates the tangential force on the first skin feature point; represents the bending moment of the first skin feature point; k represents the skin curvature.

[0021] The deformation relationship function in step A3 is as follows: in: Indicates the radial force on the t-th skin feature point, t≤s; Indicates the tangential force on the t-th skin feature point; represents the bending moment of the t-th skin feature point; The X coordinate of the skin along the skin local coordinate system tDirectional deformation quantity; Indicates the Y-directional deformation quantity of the skin along the local coordinate system of the skin t Directional deformation quantity; Indicates the angle between the tangent line of any skin feature point and the tangential force; k represents the curvature of the skin.

[0022] The deformation quantity constraint condition function in step A4 is as follows: ; Where: S represents s skin feature points; t represents the t-th skin feature point, t ≤ s; Indicates the X-directional deformation quantity of the skin along the local coordinate system of the skin t Directional deformation quantity; Indicates the Y-directional deformation quantity of the skin along the local coordinate system of the skin t Directional deformation quantity; Indicates the deformation quantity in the tangent direction at the t-th skin feature point; Indicates the deformation quantity in the normal direction at the t-th skin feature point; k represents the curvature of the skin; β t Indicates the angle between the tangent direction of any skin feature point and the horizontal direction; Indicates the deflection angle of the local coordinate system of the skin relative to the global coordinate system; k represents the curvature of the skin.

[0023] Other parts of this embodiment are the same as those of the above-mentioned Embodiment 1, so they will not be elaborated here.

[0024] Embodiment 3: This embodiment is further optimized on the basis of the above-mentioned Embodiment 1 or 2. In step 4, the formula for solving the contact points between the skin and the mold is as follows: F s (x, y) = F m (x, y); As Figures 2 - 6 shown, at least three contact points between the skin and the mold are calculated based on the formula of the contact points: 、 、 ; Where: F s (x, y) represents the skin surface function; F m (x, y) represents the mold surface function; Indicates the coordinates of contact point A; Indicates the coordinates of contact point C; Indicates the coordinates of contact point E.

[0025] In step 4, the formula for solving the highest point between the skin and the mold is as follows: ; ; Based on the formula of the highest point, the highest points of any two adjacent convex regions between the skin and the mold are calculated as: 、 ; Where: F s (x, y) represents the skin surface function; F m (x, y) represents the mold surface function; represents the coordinates of the highest point B of the first convex region; represents the coordinates of the highest point D of the second convex region.

[0026] The calculation formula for the calibration angle of any two adjacent convex regions is as follows: ; ; Where: represents the calibration angle of the first convex region; represents the calibration angle of the second convex region; represents the abscissa of the contact point A; represents the ordinate of the contact point A; represents the abscissa of the highest point B; represents the ordinate of the highest point B; represents the abscissa of the contact point C; represents the ordinate of the contact point C; represents the abscissa of the highest point D; represents the ordinate of the highest point D; represents the abscissa of the contact point E; represents the ordinate of the contact point E.

[0027] Furthermore, the critical value of the calibration angle is 85° Example 4: This example further optimizes on the basis of any one of the above Examples 1-3. S skin feature points are established on the skin, as shown in Figure 7 . A local skin coordinate system O t is established in the cutting direction of any skin feature point with respect to the global coordinate system. is the deflection angle of the local skin coordinate system O t with respect to the global coordinate system O xy . Denote the deformation amount of the skin along the X t direction of the local skin coordinate system as , and denote the deformation amount of the skin along the Y t direction of the local skin coordinate system as , β tis the angle between the tangent direction of any skin feature point and the horizontal direction, It is the angle between the tangent line and the tangential force at any skin feature point.

[0028] like Figure 8 As shown, F t Indicates the radial force on the skin feature point, P t Represents the tangential force on the skin feature point, M t Indicates the bending moment on the characteristic points of the skin.

[0029] Let R be the skin radius, L be the skin length, and k be the curvature, then: ; The first step is to construct the force relationship function between the s-1th skin feature point and the sth skin feature point as follows: ; The second step is to construct the deformation relationship function between the electromagnetic correction parameters at the skin feature points and the force deformation as follows: The third step is to establish the deformation constraint function of the skin feature points as follows: ; The force relationship function, deformation relationship function, and deformation constraint function of the simultaneous equations can realize the F of any known skin feature point. t , P t 、M t 、x t ,y t , Any three parameters can be solved to find the other three parameters.

[0030] Optimize the best electromagnetic correction force and processing method: By constraining the influence of electromagnetic correction of the raised area on the deformation of the adjacent raised area, the correction angle of the adjacent raised area must be greater than or equal to 85°, as shown in the figure, that is, it must satisfy ≥85°, ≥85°, optimize the number of electromagnetic corrections and the single electromagnetic correction force. The optimized electromagnetic correction force and processing method are as follows: Through the electromagnetic correction skin large profile peak height defect deformation prediction model, the deformation prediction model is known to F t , P t 、M t , then we can solve for x t ,y t , , solve the coordinates of any skin feature point in the global coordinate system after the electromagnetic force of different magnitudes acts on the first convex region, and then fit the different skin surface functions F formed by different electromagnetic forces s [[2]] (x, y). Establish several die feature points on the skin die, and obtain the die surface function F m (x, y).

[0031] Combine different skin surface functions F s (x, y) and the die surface function F m (x, y) to solve the contact points A, C, E and the highest points B, D.

[0032] When < 85°, the electromagnetic force is too large to meet the requirements; solve decreasing and approaching 85°, the optimal electromagnetic calibration force F of the first convex region 1max ; Repeat the above steps. When < 85°, the electromagnetic force is too large to meet the requirements; solve decreasing and approaching 85°, the optimal electromagnetic calibration force F of the second convex region 2max ; Continuously iterate the above steps until the distance between the highest point of the skin and the die is equal to the skin thickness.

[0033] The specific calculation process is as follows: 1: flag = 1; 2: while flag = 1; 3: for F t = F rmin : 5: F rmax (F rmin and F rmax respectively represent the minimum and maximum electromagnetic forces required for calibration of different materials and shapes); 4: Input P t and M t ; 5: Solve for x t and y t and parameters according to the deformation prediction model of the peak height of the large contour of the electromagnetic calibrated skin; 6: Fit the skin surface function F t (x, y) according to x t and y ; s (x, y); 7: Obtain the die surface function F m (x, y) by fitting according to the position coordinates of the die feature points; 8: Establish Fs (x, y) = F m The (x, y) relationship to find the contact point , , ; 9: Establish an equation with to obtain the highest point , ; 10: ; That is ; 11: ; 12: Output the optimal electromagnetic calibration force F applied for the first time in the first convex region 1max ; 13: end 14: end 15: for F t = F rmin :5:F rmax ; 16: Input P t , M t ; 17: Solve for x t , y t , parameters according to the deformation prediction model of the peak height of the large profile of the electromagnetic calibrated skin 18: Fit the skin surface function F t (x, y) according to x t , y ; s (x, y); 19: Fit the die surface function F m (x, y) according to the position coordinates of the die feature points 20: Establish F s (x, y) = F m (x, y) relationship to find the contact point ; 21: Establish an equation with to obtain the highest point ; 22: ; That is ; 23: if ; 24: Output the optimal electromagnetic calibration force F applied for the first time in the second convex region 2max ; 25: end 26: end 27: Determine the highest point of the skin and the distance between the mold F m and (x, y) is equal to the skin thickness; 28: If equal, then flag = 0 and stop the loop; 29: end 30: end 31: Output the optimal electromagnetic calibration force F for the first convex region 1max and the optimal electromagnetic calibration force F for the second convex region 2max .

[0034] The above are only the preferred embodiments of the present invention, and do not impose any form of limitation on the present invention. Any simple modification or equivalent change made to the above embodiments based on the technical essence of the present invention shall fall within the protection scope of the present invention.

Claims

1. A flexible electromagnetic progressive calibration method for skin continuous large contour peak height defects, characterized in that, A deformation prediction model for large contour peak height defects of electromagnetically corrected skin is established, and the deformation prediction model is used to characterize the influence of material flow caused by continuous large contour peak height defects of skin sheet metal parts during electromagnetic correcting on the deformation of adjacent correcting areas; based on the deformation prediction model, the corresponding skin surface function when electromagnetic forces of different sizes act on the raised areas of the skin is solved, and the mold surface function is established. Based on the skin surface function and the mold surface function, the correcting points of the skin in different raised areas are solved, and electromagnetic correcting forces are applied at the correcting points. The deformation prediction model is used to predict the optimal influence of the electromagnetic correcting force applied at the current correcting point on the deformation of the adjacent correcting areas. The electromagnetic correcting force corresponding to the optimal influence is input into the deformation prediction model for iterative optimization until the distance between the skin and the mold is equal to the thickness of the skin, and the optimal electromagnetic correcting force for each correcting area is output.

2. A flexible electromagnetic progressive calibration method for the peak height defect of the continuous large contour of the skin according to claim 1, characterized in that, The specific steps include: Step 1: Establish a number of skin feature points on the skin, establish the force deformation and deformation constraint conditions of the skin feature points based on the electromagnetic correction parameters at the skin feature points, and obtain a deformation prediction model; Step 2, input different electromagnetic correction parameters into the deformation prediction model, and obtain the corresponding skin surface function when electromagnetic forces of different magnitudes act on the raised area of the skin by fitting; Step 3, establishing a number of mold feature points on the skin mold, and obtaining the mold surface function based on the mold feature point fitting; Step 4: Solve the correction points of the skin in different raised areas based on the skin surface function and the mold surface function, wherein the correction points include the contact points between the skin and the mold and the highest points of the raised areas of the skin, and establish the correction angles of any two adjacent raised areas based on the contact points and the highest points; Step 5, applying an electromagnetic shaping force at the highest point of any raised area, and using the deformation prediction model to predict when the electromagnetic shaping force is applied at the current highest point, the electromagnetic shaping force corresponding to the deformation of the adjacent raised area reaches the critical value of the shaping angle, and inputting the electromagnetic shaping force into the deformation prediction model as one of the shaping parameters; Step 6, repeating steps 2 to 5 alternately in different adjacent raised areas until the distance between the highest point of the raised area and the mold is equal to the thickness of the skin, and outputting the electromagnetic shaping force applied by the raised area at this time as the optimal electromagnetic shaping force.

3. A flexible electromagnetic progressive forming method for skin continuous large contour peak height defects according to claim 2, characterized in that Establishing the deformation prediction model includes the following steps: Step A1: establishing S skin feature points on the skin based on the global coordinate system, and establishing a skin local coordinate system relative to the global coordinate system in the cutting direction of any skin feature point; Step A2, establishing a force relationship function between two adjacent skin feature points; Step A3, establishing a deformation relationship function between the electromagnetic correction parameter and the force deformation at any skin feature point; Step A4, establishing a deformation constraint function of skin feature points; Step A5: The force relationship function, the deformation relationship function, and the deformation constraint condition function are combined to obtain a deformation prediction model.

4. A flexible electromagnetic incremental calibration method for skin continuous large-profile peak height defects according to claim 3, characterized in that, The force relationship function in step A2 is as follows: ； Wherein: represents the deflection angle of the local coordinate system of the skin relative to the global coordinate system; represents the deformation in the X direction of the skin along the local coordinate system of the skin t direction; represents the deformation in the Y direction of the skin along the local coordinate system of the skin t direction; represents the radial force received by the s-th skin feature point; represents the tangential force received by the s-th skin feature point; represents the bending moment received by the s-th skin feature point; represents the radial force received by the first skin feature point; represents the tangential force received by the first skin feature point; represents the bending moment received by the first skin feature point; k represents the skin curvature.

5. A flexible electromagnetic progressive shape correction method for continuous large-profile peak height defects of a skin, characterized in that, The deformation relationship function in step A3 is as follows: Wherein: represents the radial force received by the t-th skin feature point, where t ≤ s; represents the tangential force received by the t-th skin feature point; represents the bending moment received by the t-th skin feature point; represents the deformation of the skin in the X t direction along the local coordinate system of the skin; represents the deformation of the skin in the Y t direction along the local coordinate system of the skin; represents the angle between the tangent of any skin feature point and the tangential force; k represents the curvature of the skin.

6. A flexible electromagnetic incremental calibration method for skin continuous large-profile peak height defects according to claim 5, characterized in that The deformation constraint condition function in step A4 is as follows: ； Where: S represents s skin feature points; t represents the t-th skin feature point, t ≤ s; represents the deformation of the skin along the X t direction of the global coordinate system; represents the deformation of the skin along the Y t direction of the global coordinate system; represents the deformation of the tangent direction at the t-th skin feature point; represents the deformation of the normal direction at the t-th skin feature point; k represents the curvature of the skin; β t represents the angle between the tangent direction of any skin feature point and the horizontal direction; represents the deflection angle of the local coordinate system of the skin relative to the global coordinate system; k represents the curvature of the skin.

7. A flexible electromagnetic progressive forming method for skin continuous large-profile peak height defects according to any one of claims 2-6, characterized in that In step 4, the formula for solving the contact point between the skin and the mold is as follows: F s F(x, y) = m (x, y); At least three contact points between the skin and the mold are calculated as follows: ; Where: F s (x, y) represents the skin surface function; F m (x, y) represents the mold surface function; represents the coordinates of contact point A; represents the coordinates of contact point C; represents the coordinates of contact point E.

8. A flexible electromagnetic progressive forming method for skin continuous large-profile peak height defects according to claim 7, characterized in that, In step 4, the formula for solving the highest point between the skin and the mold is as follows: ； ； The highest points of any two adjacent raised areas between the skin and the mold obtained by calculation are: ; Where: F s (x, y) represents the skin surface function; F m (x, y) represents the die surface function; represents the coordinates of the highest point B of the first raised area; represents the coordinates of the highest point D of the second raised area.

9. A flexible electromagnetic progressive forming method for skin continuous large-profile peak height defects according to claim 8, characterized in that, The calculation formula for the calibration angle of any two adjacent convex regions is as follows: ； ； Wherein: Denotes the sizing angle of the first convex region; Denotes the sizing angle of the second convex region; Denotes the abscissa of the contact point A; Denotes the ordinate of the contact point A; Denotes the abscissa of the highest point B; Denotes the ordinate of the highest point B; Denotes the abscissa of the contact point C; Denotes the ordinate of the contact point C; Denotes the abscissa of the highest point D; Denotes the ordinate of the highest point D; Denotes the abscissa of the contact point E; Denotes the ordinate of the contact point E.

10. A flexible electromagnetic progressive shape correction method for continuous large-profile peak height defects of a skin, characterized in that, The critical value of the calibration angle is 85°.

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