Modeling method and device for plate straightening process

Abstract

The invention discloses a modeling method and device for a plate straightening process, relates to the technical field of metal plate processing, and aims to solve the problem that a traditional analytical model is not comprehensive enough in description of a multi-roller straightening process in the prior art. The method comprises the steps of obtaining process information of a plate straightening process; the process information at least comprises partition reference information and process parameter information; carrying out regional division on the multi-roller straightening abstraction model on the basis of the zoning reference information to obtain three types of regions; the three types of areas comprise an entrance area, an even-number formal area and an odd-number formal area; determining a plate straightening process geometrical relationship differential model of each of the three types of regions; and based on the process parameter information, a multi-roll straightening analytical model corresponding to the geometrical relationship differential model in the plate straightening process is determined. The method is used for more comprehensively analyzing the multi-roll straightening process by adopting the multi-roll straightening analysis model constructed by the three types of regions.

Description

Technical Field

[0001] The present invention relates to the technical field of metal plate processing, and particularly relates to a modeling method and device for a sheet straightening process. Background Art

[0002] The straightening process can be used to flatten metal sheets, and at the same time can reduce and optimize the distribution of residual stresses in the sheet to facilitate subsequent further processing.

[0003] Analytical models based on various algorithms have realized the theoretical description of the straightening process. Reasonable analytical modeling will be beneficial to the online optimization control of process parameters and achieve efficient straightening of sheets.

[0004] However, there is a problem in the existing analytical models that the description of the multi-roll straightening process is not comprehensive enough. Summary of the Invention

[0005] The purpose of the present invention is to provide a modeling method and device for a sheet straightening process, which is used to improve the comprehensiveness of the analysis of the multi-roll straightening process.

[0006] To achieve the above purpose, the present invention provides the following technical solutions: In a first aspect, the present invention provides a modeling method for a sheet straightening process, including: Obtaining process information of the sheet straightening process; the process information at least includes zoning reference information and process parameter information; Based on the zoning reference information, dividing the multi-roll straightening abstraction model into regions to obtain three types of regions; the three types of regions include an entrance region, an even formal region, and an odd formal region; Determining the differential model of the geometric relationship of the sheet straightening process for each of the three types of regions; Based on the process parameter information, determining a multi-roll straightening analytical model corresponding to the differential model of the geometric relationship of the sheet straightening process.

[0007] Optionally, the determining the differential model of the geometric relationship of the sheet straightening process for each of the three types of regions includes: constructing the differential model of the geometric relationship of the sheet straightening process for each of the three types of regions based on the curvature integration method; The determining the multi-roll straightening analytical model corresponding to the differential model of the geometric relationship of the sheet straightening process based on the process parameter information includes: based on the process parameter information, using integration to process the differential model of the geometric relationship of the sheet straightening process for each type of region to obtain the multi-roll straightening analytical model for each type of region.

[0008] Optionally, the constructing the differential model of the geometric relationship of the sheet straightening process for each of the three types of regions based on the curvature integration method includes: Establish a Cartesian rectangular coordinate system in each type of region; In the Cartesian rectangular coordinate system in each type of region, determine the positive and negative signs of the target parameters, and construct a differential equation system using the curvature integral method: ; wherein, the target parameters include the coordinate azimuth angle of each point and the curvature radius of each point, is the curvature radius of each point on the sheet curve; is the coordinate azimuth angle of each point on the sheet curve; the coordinate azimuth angle is the acute angle between the tangent of each point on the sheet curve and the positive x-axis in the Cartesian rectangular coordinate system; Process the differential equation system to obtain the geometric relationship differential model of the sheet straightening process: .

[0009] Optionally, determining the positive and negative signs of the target parameters in the Cartesian rectangular coordinate system in each type of region includes: Determine the positive and negative signs of the coordinate azimuth angle according to the quadrant position of the coordinate azimuth angle of each point in the Cartesian rectangular coordinate system; when the coordinate azimuth angle of each point is in the first quadrant, the sign of the coordinate azimuth angle is positive; when the coordinate azimuth angle of each point is in the fourth quadrant, the sign of the coordinate azimuth angle is determined to be negative.

[0010] Optionally, determining the positive and negative signs of the target parameters includes: Determine the positive and negative signs of the curvature radius of each point according to the positional relationship between the center of curvature corresponding to the curvature radius of each point and the sheet curve; when the center of curvature is above the sheet curve, the sign of the curvature radius of each point is positive; when the center of curvature is below the sheet curve, the sign of the curvature radius of each point is determined to be negative.

[0011] Optionally, processing the differential equation system includes: Adopt the application approximation conditions: and , and simplify the differential equation system.

[0012] Optionally, based on the process parameter information, using the integral method to process the geometric relationship differential model of the sheet straightening process for each type of region to obtain the multi-roll straightening analytical model for each type of region, at least including: For each type of region among the three types of regions, perform integral calculation on the geometric relationship differential model of the sheet straightening process to obtain the first calculation result: ; Among them, is the curvature of each point on the plate curve, is the projection coordinate of each point on the plate curve in the x direction, and are integration constants; Based on the first calculation result, determine the multi-roll straightening analytical model for each of the three types of regions.

[0013] Optionally, the process parameter information further includes the roll pitch between the geometric centers of two adjacent straightening rolls on the x-axis, the distance between the edge points of two adjacent straightening rolls on the z-axis, the roll radius of each straightening roll, the boundary conditions of the first set point, and the boundary conditions of the second set point; The determining the multi-roll straightening analytical model for each of the three types of regions based on the first calculation result includes: For the entrance area, substitute the boundary conditions of the first set point into the first calculation result for calculation, and the second calculation result is: ; Combined with the roll pitch between the geometric centers of two straightening rolls in the entrance area on the x-axis, the distance between the edge points of two adjacent straightening rolls in the entrance area on the z-axis, and the roll radius of the straightening rolls in the entrance area, substitute the boundary conditions of the second set point into the second calculation result for calculation, and the third calculation result is: ; Determine the third calculation result as the multi-roll straightening analytical model for the entrance area; Among them, is the distance between two adjacent contact points on the first straightening roll and the second straightening roll in the x-axis direction; is the acute angle between the line connecting the contact point and the geometric center on the first straightening roll and the z-axis; is the acute angle between the line connecting the contact point and the geometric center on the second straightening roll and the z-axis; is the inner integral variable; is the roll radius of the straightening roll; is the roll pitch between the geometric center of the first straightening roll and the geometric center of the second straightening roll in the x-axis direction; is the distance between the edge point close to the plate side among the upper and lower edge points of the first straightening roll and the edge point close to the plate side among the upper and lower edge points of the second straightening roll in the z-axis direction.

[0014] Optionally, the determining the multi-roll straightening analytical model for each of the three types of regions based on the first calculation result includes: For the even formal area or the odd formal area, substitute the boundary conditions of the first set point into the first calculation result for calculation to obtain a fourth calculation result: ; Combined with the roll pitch between the geometric centers of two straightening rolls in the x-axis in the even formal area or the odd formal area, the distance between the edge points of two adjacent straightening rolls in the z-axis in the even formal area or the odd formal area, and the roll radius of the straightening roll in the even formal area or the odd formal area, substitute the boundary conditions of the second set point into the fourth calculation result for calculation to obtain a fifth calculation result: ; Determine the fifth calculation result as the multi-roll straightening analysis model for the even formal area or the odd formal area; Among them, is the distance between two adjacent contact points on the i-th straightening roll and the (i + 1)-th straightening roll in the x-axis direction; is the roll pitch between the geometric centers of the i-th straightening roll and the (i + 1)-th straightening roll in the x-axis direction; is the acute angle between the line connecting the contact point and the geometric center on the i-th straightening roll and the z-axis; is the acute angle between the line connecting the contact point and the geometric center on the (i + 1)-th straightening roll and the z-axis; is the distance between the edge point closer to the sheet on the upper and lower edge points of the i-th straightening roll and the edge point closer to the sheet on the upper and lower edge points of the (i + 1)-th straightening roll in the z-axis direction; is the roll radius of the straightening roll.

[0015] The beneficial effects of the present invention are as follows: Compared with the prior art, a modeling method for a sheet straightening process provided by the present invention changes the traditional two-area division method, divides the multi-roll straightening abstract model into three types of areas, namely, the entrance area, the even formal area, and the odd formal area, based on the partition reference information in the process information, and constructs a multi-roll straightening analysis model for each type of area among the three types of areas based on the process parameter information. The finally obtained multi-roll straightening analysis model can more comprehensively describe and analyze the multi-roll straightening process.

[0016] In the second aspect, the present invention also provides a modeling device for a sheet straightening process, including: An acquisition module for acquiring the process information of the sheet straightening process; the process information at least includes partition reference information and process parameter information; A partitioning module, configured to partition the multi-roll straightening abstraction model into three types of regions based on the partition reference information; the three types of regions include an entrance region, an even formal region, and an odd formal region; A first determination module, configured to determine a differential model of the geometric relationship in the sheet straightening process for each of the three types of regions; A second determination module, configured to determine a multi-roll straightening analytical model corresponding to the differential model of the geometric relationship in the sheet straightening process based on the process parameter information. Description of the Drawings

[0017] The drawings described herein are used to provide a further understanding of the present invention and constitute a part of the present invention. The schematic embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation to the present invention. In the drawings: Figure 1 FIG. 1 is a schematic flow chart of a method for modeling a sheet straightening process according to an embodiment of the present invention; Figure 2 FIG. 2 is a schematic structural diagram of a multi-roll straightening abstraction model according to an embodiment of the present invention; Figure 3 FIG. 3 is a schematic diagram of the state of the multi-roll straightening abstraction model after being partitioned into three types of regions according to an embodiment of the present invention; Figure 4 FIG. 4 is a schematic flow chart of a method for modeling a sheet straightening process according to an embodiment of the present invention; Figure 5 FIG. 5 is a schematic diagram of a coordinate azimuth angle according to an embodiment of the present invention; Figure 6 FIG. 6 is an analysis diagram of the sheet straightening process in the entrance region according to an embodiment of the present invention; Figure 7 FIG. 7 is an analysis diagram of the sheet straightening process in the odd formal region according to an embodiment of the present invention; Figure 8 FIG. 8 is an analysis diagram of the sheet straightening process in the even formal region according to an embodiment of the present invention; Figure 9 FIG. 9 is a schematic structural diagram of a device for modeling a sheet straightening process according to an embodiment of the present invention. Detailed Embodiments

[0018] For the convenience of clearly describing the technical solutions of the embodiments of the present invention, in the embodiments of the present invention, terms such as "first" and "second" are used to distinguish identical or similar items with basically the same functions and roles. For example, the first threshold and the second threshold are only used to distinguish different thresholds, and do not limit their sequence. Those skilled in the art can understand that terms such as "first" and "second" do not limit the quantity and execution order, and the terms "first" and "second" do not necessarily limit being different from each other.

[0019] It should be noted that in the present invention, words such as "exemplary" or "for example" are used to represent examples, illustrations or explanations. Any embodiment or design solution described as "exemplary" or "for example" in the present invention should not be construed as being more preferred or having more advantages than other embodiments or design solutions. Exactly speaking, the use of words such as "exemplary" or "for example" is intended to present related concepts in a specific manner.

[0020] In the present invention, "at least one" means one or more, and "a plurality of" means two or more. "And / or" describes the association relationship of associated objects, indicating that three relationships can exist.

[0021] As Figure 1 shown, the present invention provides a modeling method for a sheet straightening process, which may include: Step 100: Obtain the process information of the sheet straightening process; the process information includes at least zoning reference information and process parameter information; The process information refers to various information involved in the sheet straightening process. In addition to including zoning reference information and process parameter information, the process information may further include a multi-roll straightening abstraction model, the number of each straightening roll among a plurality of straightening rolls, and the contact point position between each straightening roll and the sheet. For the multi-roll straightening abstraction model, refer to Figure 2 , for example Figure 2 the numbers of each straightening roll in may be numbered sequentially from left to right. This figure shows a schematic diagram of the straightening process of the sheet in a multi-roll straightening device. Figure 2 The circles in represent straightening rolls, and the sheet passes between multiple groups of straightening rolls. , , , , represent the wrap angles at the contact points between the sheet and each straightening roll (that is, the acute angle between the line connecting the contact point on the straightening roll and the geometric center of the roll and the z-axis), that is, the angle range covered by the sheet when it contacts the straightening roll. The subscripts 1, 2, 3, 4, and 5 are the numbers of the straightening rolls.

[0022] Step 200: Based on the partition reference information, divide the multi-roll straightening abstraction model into three types of regions; the three types of regions include an entrance region, an even formal region, and an odd formal region; see Figure 3 .

[0023] It should be noted that in all the attached drawings, the even formal region is abbreviated as the even region, and the odd formal region is abbreviated as the odd region.

[0024] For example, step 200 may specifically include: Number all the straightening rolls in sequence from left to right; Taking the positions of two adjacent contact points as the boundaries, determine the sheet curve between the first straightening roll and the second straightening roll as the entrance region; see Figure 3 as shown.

[0025] Taking the positions of two adjacent contact points as the boundaries, if the number of the straightening roll corresponding to the contact point position closest to the entrance region is even, then determine the sheet curve between the two adjacent straightening rolls as the even formal region; see Figure 3 as shown.

[0026] Taking the positions of two adjacent contact points as the boundaries, if the number of the straightening roll corresponding to the contact point position closest to the entrance region is odd, then determine the sheet curve between the two adjacent straightening rolls as the odd formal region. See Figure 3 as shown.

[0027] Analysis of the beneficial effects of this embodiment: In the multi-roll straightening process, the area division is carried out according to the different positions and states of the sheet during multi-roll straightening. Specifically, it is divided according to the relative position relationship between the sheet and the straightening rolls and the deformation characteristics of the sheet during straightening. The solution in the prior art adopts a two-area division method (only the even area and the odd area), but does not consider the analytical modeling of the roll system inlet area, which results in the subsequent established analytical model being incomplete and imperfect, and further leads to deficiencies in the analysis of the overall sheet after the analytical model is established. Compared with the prior art, a modeling method for a sheet straightening process provided by the present invention changes the roll system area division strategy, divides the straightening roll system into an inlet area and a formal area, and the straightening rolls in the formal area are paired in pairs to form an odd formal area and an even formal area. Among them, the inlet area is the part where the sheet just enters the straightening roll group. In this area, the initial state of the sheet has an important impact on the subsequent straightening process; while the formal area is the remaining part of the straightening roll group after the sheet passes through the inlet area. According to the parity of the number of the roll closest to the inlet area, it is further divided into an odd formal area and an even formal area. There may be some differences in the force and deformation of the sheet in different formal areas. Such a division helps to more carefully analyze and describe the behavior of the sheet during the entire straightening process. After the area division, a multi-roll straightening analytical model for each type of area is constructed based on the geometric relationship between the sheet and the straightening rolls. The changed roll system area division strategy is more complete in the analytical modeling of the straightening process, and can make the multi-roll straightening analytical model more comprehensive in the analysis of the sheet straightening process.

[0028] Step 300: Determine the differential model of the geometric relationship of the sheet straightening process for each type of area among the three types of areas; Step 300 is specifically: Based on the curvature integration method, construct the differential model of the geometric relationship of the sheet straightening process for each type of area among the three types of areas.

[0029] Step 400: Based on the process parameter information, determine the multi-roll straightening analytical model corresponding to the differential model of the geometric relationship of the sheet straightening process.

[0030] Step 400 is specifically: Based on the process parameter information, adopt the integral method to process the differential model of the geometric relationship of the sheet straightening process for each type of area to obtain the multi-roll straightening analytical model for each type of area.

[0031] Analysis of the beneficial effects of this embodiment: As can be seen from the above content, in this embodiment, when constructing the multi-roll straightening analysis model for each type of region, the curvature integration method is used as the modeling basis. The reasons are as follows: First, for the straightening of plates in different types of regions, the curvature integration method has good versatility. Regardless of the deformation stage of the plate during the straightening process or the characteristics of the region, a differential model of geometric relationships can be constructed based on the curvature integration, and then the multi-roll straightening analysis model can be further obtained. Second, during the plate straightening process, the curvature change is the core factor. The curvature integration method directly builds a model based on the curvature, which can accurately describe the bending deformation characteristics of the plate during straightening and is more in line with the physical essence of straightening. When describing the process of the plate being gradually straightened from the initial bent state, the curvature integration method can intuitively show the deformation accumulation of the plate at different straightening stages through the integration operation of the curvature, and accurately present the change of the plate shape with the straightening process. Third, the model can be closely combined with process parameter information. During the integration process, process parameters such as roll pitch and roll diameter can be incorporated into the calculation to accurately analyze the influence of these parameters on the straightening effect. For example, taking the roll pitch as an example, through the curvature integration method, it can be clearly seen how the change of the roll pitch changes the curvature integration result of the plate, thereby affecting the final straightening accuracy, which helps to optimize the combination of process parameters and improve the straightening quality.

[0032] For example Figure 4 As shown, step 300 may specifically include: Step 311: Establish a Cartesian rectangular coordinate system in each type of region, with the origin being the left boundary point where the plate is tangent to the left straightening roll when contacting it. This left boundary point is also the starting point of each type of region. It can be understood that the right boundary point where the plate is tangent to the right straightening roll when contacting it is the end point in each type of region; the Cartesian rectangular coordinate system includes at least the horizontal x-axis and the vertical z-axis.

[0033] Step 312: In the Cartesian rectangular coordinate system in each type of region, determine the positive and negative signs of the target parameters, and use the curvature integration method to construct a differential equation system: (1) Among them, the target parameters include the coordinate azimuth angle and the radius of curvature, is the radius of curvature of each point on the plate curve; is the coordinate azimuth angle of each point on the plate curve (reflecting the inclination direction of the tangent line at a certain point on the plate curve relative to the positive direction of the x-axis); is the infinitesimal change of the coordinate azimuth angle; the coordinate azimuth angle is the acute angle between the tangent line of each point on the plate curve and the positive direction of the x-axis in the Cartesian rectangular coordinate system. See Figure 5 as shown. is the infinitesimal length change in the x-axis direction of the Cartesian rectangular coordinate system; is the infinitesimal length change in the z-axis direction of the Cartesian rectangular coordinate system.

[0034] It is understandable that the plate curve refers to the actual shape curve presented by the plate during the multi-roll straightening process in the Cartesian rectangular coordinate system (including the horizontal x-axis and the vertical z-axis). See Figure 2 and Figure 3 , and the plate curve characterizes the relationship between the geometric characteristics of the plate and the geometric characteristics of the straightening rolls.

[0035] In the Cartesian rectangular coordinate system of each type of region in step 312, determining the positive and negative signs of the target parameters may specifically include: 1) Determining the positive and negative signs of the coordinate azimuth angles according to the quadrant positions of the coordinate azimuth angles of each point in the Cartesian rectangular coordinate system; when the coordinate azimuth angles of each point are in the first quadrant, the sign of the coordinate azimuth angle is positive; when the coordinate azimuth angles of each point are in the fourth quadrant, the sign of the coordinate azimuth angle is determined to be negative.

[0036] It is understandable that in the setting of this embodiment, the coordinate azimuth angles of each point will not be in the second quadrant and the third quadrant, and the above solutions cover all cases.

[0037] Analysis of the beneficial effects of this embodiment: The reason for determining the positive and negative signs of the coordinate azimuth angles of each point (i.e., each point) before constructing the differential equations is that in the prior art, the definitions of the coordinate azimuth angles of each point include both acute angles and obtuse angles. Since the positive and negative signs of the coordinate azimuth angles cannot be determined all the time, it is rather troublesome for the model to calculate actually. In order to facilitate the calculation and redefine the coordinate azimuth angles of each point during the model construction process in this application, the positive and negative signs of the coordinate azimuth angles are determined in advance. In this way, it is conducive to the calculation during the operation after the model is successfully constructed, and the calculation efficiency and accuracy of the model are improved.

[0038] 2) Determining the positive and negative signs of the radius of curvature of each point according to the positional relationship between the center of curvature corresponding to the radius of curvature of each point and the plate curve; when the center of curvature is above the plate curve, the sign of the radius of curvature of each point is positive; when the center of curvature is below the plate curve, the sign of the radius of curvature of each point is determined to be negative.

[0039] Analysis of the beneficial effects of this embodiment: It is understandable that the determination of the positive and negative signs of the radius of curvature can also improve the calculation efficiency and accuracy of the model, just like the determination of the positive and negative signs of the coordinate azimuth angle.

[0040] The specific calculation process of step 1) may include: Determine the representation of the plate curve: Assume that the plate curve is represented by a series of discrete points stored in a list, e.g., curve_points = [(x1, z1), (x2, z2),..., (xn, zn)]. To calculate the tangent at a certain point, at least two adjacent points are required.

[0041] Calculate the tangent slope at a certain point: For a certain point on the plate curve, approximate the tangent slope through this point and its adjacent point. The tangent slope k can be calculated using the formula k = (z2 - z1) / (x2 - x1) (provided that x2 - x1 is not equal to 0).

[0042] Calculate the tangent angle based on the slope: Use the arctangent function atan to calculate the angle (in radians) between the tangent and the positive x-axis. In Python, the math.atan function can be used. The obtained angle value range is (-π / 2, π / 2), and this range corresponds to the angle range from the fourth quadrant to the first quadrant.

[0043] Judge the quadrant where the tangent is located and determine the sign: Determine whether the tangent is in the first quadrant or the fourth quadrant based on the calculated angle, so as to determine the sign of the coordinate azimuth angle.

[0044] The specific calculation process of step 2) is as follows: Determine the representation of the plate curve: Assume that the plate curve is represented by a series of discrete points stored in a list, e.g., curve_points = [(x1, z1), (x2, z2),..., (xn, zn)]. To calculate the tangent at a certain point, at least three adjacent points are required.

[0045] Call the function calculate_curvature_center (this function is used to calculate the coordinates of the curvature center of an arc formed by three given points) to calculate the curvature center of the arc formed by three adjacent points. This function takes three points p1, p2, and p3 as parameters (the three points p1, p2, and p3, each point is a binary tuple in the form of (x, z), representing the x-coordinate and z-coordinate of the point in the two-dimensional plane). Inside the function, the coordinates of the curvature center are obtained by calculating the intersection point of the perpendicular bisectors of the line segments formed by these three points. The specific calculation steps are as follows: First, calculate the coordinates of the midpoint mid1 of p1 and p2 and the midpoint mid2 of p2 and p3; then, calculate the slopes slope1 and slope2 of the perpendicular bisectors of the lines connecting p1 and p2 and p2 and p3. When calculating the slope, it is checked whether the denominator is zero to avoid division-by-zero errors. If the denominator is zero, the slope is set to infinity; finally, depending on different situations, the intersection point of the two perpendicular bisectors, that is, the coordinates (x, z) of the curvature center, is calculated. If the slope of a perpendicular bisector is infinity, the intersection point coordinates are calculated according to the equation of the other perpendicular bisector; if the slopes of both perpendicular bisectors are not infinity, the intersection point coordinates are obtained by solving the system of equations of the two lines.

[0046] Next, call the function determine_curvature_sign (the function's function: determine the sign of the curvature radius of each point on the sheet curve) to implement the judgment logic. This function receives the discrete point list curve_points of the sheet curve as input. For each point except the first and last points, select its three adjacent points and call the calculate_curvature_center function to calculate the curvature center. Then, extract their vertical coordinates from these three points to obtain the vertical coordinate of the curvature center. The specific implementation steps are as follows: 1) Initialize an empty list signs to store the signs of the curvature radii of each point; 2) Traverse the curve_points list, excluding the first and last points (because three adjacent points are required to calculate the curvature radius); 3) For each intermediate point, select its three adjacent points p1, p2, and p3, and call the calculate_curvature_center function to calculate the coordinates (center_x, center_z) of the curvature center of the arc formed by these three points; 4) Obtain the z coordinates z1, z2, and z3 of these three points; 5) Compare the z coordinate center_z of the curvature center with the maximum and minimum values of z1, z2, and z3: If center_z is greater than the maximum value of z1, z2, and z3, set the sign of the curvature radius to 1; if center_z is less than the minimum value of z1, z2, and z3, set the sign of the curvature radius to -1; if center_z is between the minimum and maximum values of z1, z2, and z3, set the sign of the curvature radius to 0; 6) Add the calculated sign of the curvature radius to the signs list; 7) After the traversal, return the signs list.

[0047] The rationality of determining the positive and negative signs of the target parameters in 1) and 2) can be verified through the following derivation process: First, refer to Figure 6 , taking the entrance area as an example, verify the rationality of the corrected angle Define the rationality, including the following steps: ① Examine the curvature radius of point A (any point on the curved shape of the sheet in the entrance area) , its center is located below the curve, so is negative.

[0048] ② Examine the and of point A. There are small changes in the value in the curve micro-segment near this point. The acute angle between the curve tangent and the positive x-axis is increasing, and it is in the fourth quadrant, so is negative. At the same time, is a negative acute angle, so is positive.

[0049] ③ Examine the at point A. There is also a small change in the x value in the small curve segment near this point, and the x value is increasing positively, so is positive.

[0050] ④ From the above steps, it can be seen that The signs on both sides of the equation are positive. At the same time, it is easy to know from the geometric relationship that the absolute values on both sides of the equation are equal. Therefore, this differential equation system holds at point A in the entrance region. After verification, the rest of the points in this section also hold.

[0051] Second, take the odd formal region as an example. See Figure 7 ( Figure 7 In the odd formal region is simply called the odd region), verify the rationality of the definition of the corrected angle including the following steps: ⑤ Examine the radius of curvature at point A. Its center is located below the curve, so is negative.

[0052] ⑥ Examine the and at point A. There is a small change in the value in the small curve segment near this point. The acute angle between the curve tangent and the positive x-axis is getting smaller and is in the first quadrant at the same time, so is negative. At the same time, is a positive acute angle, so is positive.

[0053] ⑦ Examine the at point A. There is also a small change in the x value in the small curve segment near this point, and the x value is increasing positively, so is positive.

[0054] ⑧ From the above steps, it can be seen that The signs on both sides of the equation are positive. At the same time, it is easy to know from the geometric relationship that the absolute values on both sides of the equation are equal. Therefore, this differential equation system holds at point A in the odd formal region. After verification, the rest of the points in this section also hold.

[0055] Third, take the even formal region as an example. See Figure 8 ( Figure 8 In the even formal region is simply called the even region) to verify the rationality of the definition of the corrected angle including the following steps: ⑨ Examine the radius of curvature at point A. Its center is located above the curve, so is positive.

[0056] ⑩Examine the and at point A. There is a small change in the value of in the infinitesimal curve segment near this point. The acute angle between the tangent of the curve and the positive direction of the x-axis is getting smaller and is in the fourth quadrant at the same time. Therefore, is positive. At the same time, is a negative acute angle. Therefore, is positive.

[0057] Examine the at point A. There is also a small change in the x value in the infinitesimal curve segment near this point. The x value is increasing positively. Therefore, is positive.

[0058] From the above steps, it can be seen that The signs on both sides of the equation are positive. At the same time, it is easy to know from the geometric relationship that the absolute values on both sides of the equation are equal. Therefore, this system of differential equations holds at point A in the even formal region. After verification, the remaining points in this section also hold.

[0059] Step 313: Process the system of differential equations to obtain the differential model of the geometric relationship in the plate straightening process: (2) Specifically, step 313 is as follows: Apply the approximation conditions: and , and simplify the system of differential equations to obtain the above differential model of the geometric relationship in the plate straightening process.

[0060] Regarding the above application of approximation conditions, it is considered that in the actual plate straightening process, is very small. Therefore, let , .

[0061] After the differential model of the geometric relationship in the plate straightening process is successfully constructed, the next step is to process it based on integral calculation, that is, to perform step 400.

[0062] Step 400 can specifically include the first step and the second step: The first step: For each of the three types of regions, perform integral calculation on the differential model of the geometric relationship in the plate straightening process to obtain the first calculation result: (3) Among them, is the coordinate azimuth angle at the x coordinate on the plate curve, that is, the acute angle between the tangent of the curve at this point and the positive direction of the x-axis. It is a function of x and changes with the change of the x coordinate is the curvature of each point on the plate curve and is a function of t. and are reciprocals of each other; is the projection coordinate of each point on the plate curve in the x direction and is the integration variable; and are integration constants; is the z-axis coordinate value at the x coordinate on the plate curve and is a function of x, describing the change of the position of the plate in the z direction with x; is the inner integration variable for calculating the inner integral and is also a variable related to the x direction.

[0063] Step 2: Based on the first calculation result, determine the multi-roll straightening analytical model for each of the three types of regions.

[0064] It should be noted that the process parameter information also includes the roll pitch of the geometric centers of two adjacent straightening rolls on the x-axis , the spacing between the edge points of two adjacent straightening rolls on the z-axis , the roll radius of each straightening roll (assuming that the radii of all straightening rolls are the same), the boundary conditions of the first set point and the boundary conditions of the second set point, etc. The first set point is the starting point of each type of region, and the second set point is the ending point of each type of region. Regarding the starting point and the ending point, the above has been introduced and will not be elaborated here. Among them, the boundary conditions include the position coordinates of the set point and the coordinate azimuth angle at the set point. For example Figure 6 , the coordinate azimuth angle of the first set point (i.e., the origin of coordinates) in the entrance region is .

[0065] For the entrance region, Step 2 specifically includes: Substitute the boundary conditions of the first set point into the first calculation result for calculation, and the integration constants and can be determined, where , , so that the second calculation result is: (4) Combined with the roll pitch of the geometric centers of two straightening rolls in the entrance region on the x-axis, the spacing between the edge points of two adjacent straightening rolls in the entrance region on the z-axis, and the roll radius of the straightening rolls in the entrance region, substitute the boundary conditions of the second set point into the second calculation result for calculation, and the third calculation result is: (5) Determine the third calculation result as the multi-roll straightening analytical model (i.e., the curvature integral model) of the entrance region, where is the integral of the curvature on the plate curve from the starting point to where the curvature is integrated, reflecting the cumulative change in the coordinate azimuth angle from the starting point to the position; is the distance between two adjacent contact points on the first straightening roll and the second straightening roll in the x-axis direction; is the acute angle between the line connecting the contact point on the first straightening roll (e.g., the left straightening roll) and the geometric center of the roll and the z-axis (i.e., is the coordinate azimuth angle of the first straightening roll); is the acute angle between the line connecting the contact point on the second straightening roll (e.g., the right straightening roll) and the geometric center of the roll and the z-axis (i.e., is the coordinate azimuth angle of the second straightening roll); is the result of integrating the curvature once again, comprehensively considering the influence of curvature change and the initial angle on the position of the plate in the direction, is the inner integral variable; is the roll radius of the straightening roll; is the roll spacing between the geometric centers of the first straightening roll and the second straightening roll in the x-axis direction; is the distance between the edge point closer to the plate among the upper and lower edge points of the first straightening roll and the edge point closer to the plate among the upper and lower edge points of the second straightening roll in the z-axis direction; , , are all known quantities, , are the quantities to be determined, , are unknown quantities. Similarly to , the meanings of Figure 7 and Figure 8 in the appendix and will not be elaborated one by one. Similarly to , the meanings of Figure 7 and Figure 8 in the appendix and will not be elaborated one by one. Similarly to , the meanings of Figure 7 and Figure 8 in the appendix and will not be elaborated one by one.

[0066] For the even formal area or the odd formal area, the second step specifically includes: Substitute the boundary conditions of the first set point into the first calculation result for calculation to obtain the fourth calculation result: (6) Wherein, is the angle correction term related to the i-th leveling roll, is the acute angle between the line connecting the contact point on the i-th leveling roll and the geometric center of the roll and the z-axis, used to adjust the sign.

[0067] Combined with the roll pitch between the geometric centers of two leveling rolls on the x-axis in the even formal area or the odd formal area, the spacing between the edge points of two adjacent leveling rolls on the z-axis in the even formal area or the odd formal area, and the roll radius of the leveling roll in the even formal area or the odd formal area, substitute the boundary conditions of the second set point into the fourth calculation result for calculation to obtain the fifth calculation result: (7) Wherein, is the integral of the curvature of the plate curve from the starting point 0 to at, reflecting the change in the coordinate azimuth angle; is the spacing between two adjacent contact points on the i-th leveling roll and the (i + 1)-th leveling roll in the x-axis direction; is the roll pitch between the geometric centers of the i-th leveling roll and the (i + 1)-th leveling roll in the x-axis direction; is the acute angle between the line connecting the contact point on the i-th leveling roll and the geometric center of the roll and the z-axis (i.e., is the coordinate azimuth angle of the i-th leveling roll); is the acute angle between the line connecting the contact point on the (i + 1)-th leveling roll and the geometric center of the roll and the z-axis (i.e., is the coordinate azimuth angle of the (i + 1)-th leveling roll); is the spacing between the edge point closer to the plate among the upper and lower edge points of the i-th leveling roll and the edge point closer to the plate among the upper and lower edge points of the (i + 1)-th leveling roll in the z-axis direction; is the roll radius of the leveling roll; is the roll radius; , , are all known quantities, , are the quantities to be determined, , are the unknown quantities.

[0068] Determine the fifth calculation result as the multi-roll leveling analysis model for the even formal area or the odd formal area.

[0069] It should be noted that the establishment of the above multi-roll straightening analysis model only involves the establishment of the curvature integral model, and the specific solution , and other quantities to be calculated should be combined with the corresponding bending moment curvature model.

[0070] In summary, in the embodiment of the present invention, the straightening area is first re-divided, which is beneficial to the comprehensive description of the multi-roll straightening process and is conducive to the subsequent more comprehensive analysis of the multi-roll straightening process using the model; secondly, a new and clear definition is given to the coordinate azimuth angles of each point on the plate curve in the multi-straightening roll analysis model, which is beneficial to model calculation, improves the model operation efficiency, and further facilitates the more comprehensive analysis of the multi-roll straightening process.

[0071] After constructing the multi-roll straightening analysis model, in the plate straightening process, online control of process parameters can be carried out based on the multi-roll straightening analysis modeling. The main process parameters that can be controlled online are as follows: The pressure of the straightening roll: The pressure exerted by the straightening roll on the plate is a key parameter affecting the straightening effect. The analysis model can calculate the required straightening roll pressure at different positions and stages according to the mechanical properties and straightening requirements of the plate, and realize online adjustment, so that the residual stress inside the plate is reasonably distributed and a better flatness is achieved.

[0072] The spacing between the straightening rolls: The spacing between the straightening rolls determines the bending degree and the distribution of the force application points of the plate during the straightening process. Through the analysis model, the spacing between the straightening rolls can be optimized according to parameters such as the thickness and strength of the plate, and online adjustment can be realized, so that the plate can be straightened according to the expected curvature change, improving the straightening efficiency and quality.

[0073] The device provided by the present invention will be described below. The device described below can be correspondingly referred to the method described above.

[0074] As Figure 9 shown, the embodiment of the present invention also provides a modeling device for the plate straightening process, which is used to implement the modeling method of the plate straightening process in any of the above embodiments. The modeling device for the plate straightening process may include: An acquisition module 910, configured to acquire process information of the plate straightening process; the process information at least includes zoning reference information and process parameter information; A partitioning module 920, configured to partition the multi-roll straightening abstraction model based on the zoning reference information to obtain three types of regions; the three types of regions include an entrance region, an even formal region, and an odd formal region; A first determination module 930, configured to determine the differential model of the geometric relationship of the plate straightening process in each of the three types of regions; A second determination module 940, configured to determine a multi-roll straightening analysis model corresponding to the geometric relationship differential model of the sheet straightening process based on the process parameter information.

[0075] An embodiment of the present invention further provides an electronic device, which may include: a processor, a communication interface, a memory, and a communication bus. Among them, the processor, the communication interface, and the memory complete communication with each other through the communication bus. A computer program executable by the processor is stored on the memory; when the processor runs the computer program, it can execute the modeling method of the sheet straightening process in any of the above embodiments.

[0076] In addition, when the logical instructions in the above-mentioned memory are implemented in the form of software functional units and sold or used as independent products, they can be stored in a computer-readable storage medium. Based on such an understanding, the technical solution of the present invention, in essence, or the part that contributes to the prior art, or a part of this technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions for causing a computer device (which may be a personal computer, a server, or a network device, etc.) to execute all or part of the steps of the methods in various embodiments of the present invention. The foregoing storage medium includes: various media such as USB flash drives, mobile hard disks, read-only memories, random access memories, magnetic disks, or optical discs that can store program codes.

[0077] On the other hand, the present invention also provides a non-transitory computer-readable storage medium. Instructions are stored in the computer storage medium, and when the instructions are run, the modeling method of the sheet straightening process in any of the above embodiments is implemented.

[0078] Although the present invention has been described in conjunction with various embodiments herein, however, in the process of implementing the claimed invention, those skilled in the art can understand and implement other variations of the disclosed embodiments by viewing the drawings, the disclosure, and the appended claims. In the claims, the word "comprising" does not exclude other components or steps, and "a" or "an" does not exclude a plurality. A single processor or other unit can implement several functions recited in the claims. Certain measures are recited in mutually different dependent claims, but this does not mean that these measures cannot be combined to produce good results.

[0079] Although the present invention has been described in connection with specific features and their embodiments, it will be apparent that various modifications and combinations can be made without departing from the spirit and scope of the invention. Accordingly, the present specification and drawings are merely illustrative of the invention defined by the appended claims and are considered to cover any and all modifications, variations, combinations, or equivalents within the scope of the invention. Obviously, those skilled in the art can make various changes and modifications to the present invention without departing from the spirit and scope of the invention. Thus, if these modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalent technologies, the present invention is also intended to include these changes and modifications.

Claims

1. A modeling method for a sheet straightening process, characterized in that, Including: Obtaining the process information of the plate straightening process; The process information at least includes zoning reference information and process parameter information; Based on the zoning reference information, dividing the multi-roll straightening abstraction model into regions to obtain three types of regions; the three types of regions include an entrance region, an even formal region, and an odd formal region; Determining the differential model of the geometric relationship in the plate straightening process for each of the three types of regions; Based on the process parameter information, determining a multi-roll straightening analytical model corresponding to the differential model of the geometric relationship in the plate straightening process.

2. The modeling method of the sheet metal straightening process according to claim 1, characterized in that The determining the differential model of the geometric relationship in the plate straightening process for each of the three types of regions includes: constructing the differential model of the geometric relationship in the plate straightening process for each of the three types of regions based on the curvature integration method; The determining the multi-roll straightening analytical model corresponding to the differential model of the geometric relationship in the plate straightening process based on the process parameter information includes: based on the process parameter information, using integration to process the differential model of the geometric relationship in the plate straightening process for each type of region to obtain the multi-roll straightening analytical model for each type of region.

3. The modeling method of the sheet straightening process according to claim 2, characterized in that, The constructing the differential model of the geometric relationship in the plate straightening process for each of the three types of regions based on the curvature integration method includes: Establishing a Cartesian rectangular coordinate system in each type of region; In the Cartesian rectangular coordinate system in each type of region, determining the positive and negative signs of the target parameters, and using the curvature integration method to construct a system of differential equations: ； Among them, the target parameters include the coordinate azimuth angles of each point and the curvature radius of each point. is the curvature radius of each point on the curve of the sheet material; is the coordinate azimuth angle of each point on the curve of the sheet material; the coordinate azimuth angle is the acute angle between the tangent of each point on the curve of the sheet material and the positive direction of the x-axis in the Cartesian rectangular coordinate system. Processing the system of differential equations to obtain the differential model of the geometric relationship in the plate straightening process: 。 4. The modeling method of the sheet straightening process according to claim 3, characterized in that, Including: The determining the positive and negative signs of the target parameters in the Cartesian rectangular coordinate system in each type of region includes: Determining the positive and negative signs of the coordinate azimuth angle according to the quadrant position of the coordinate azimuth angle of each point in the Cartesian rectangular coordinate system; When the coordinate azimuth angle of each point is in the first quadrant, the sign of the coordinate azimuth angle is positive; when the coordinate azimuth angle of each point is in the fourth quadrant, the sign of the coordinate azimuth angle is determined to be negative.

5. The modeling method of the sheet straightening process according to claim 3, wherein The determining the positive and negative signs of the target parameters includes: Determining the positive and negative signs of the curvature radius of each point according to the positional relationship between the center of curvature corresponding to the curvature radius of each point and the plate curve; when the center of curvature is above the plate curve, the sign of the curvature radius of each point is positive; when the center of curvature is below the plate curve, the sign of the curvature radius of each point is determined to be negative.

6. The modeling method of the sheet straightening process according to claim 3, characterized in that, The processing the system of differential equations includes: Apply the approximation conditions: and , and simplify the differential equation set.

7. The modeling method of the sheet straightening process according to claim 6, characterized in that, The using integration to process the differential model of the geometric relationship in the plate straightening process for each type of region based on the process parameter information to obtain the multi-roll straightening analytical model for each type of region at least includes: For each of the three types of regions, performing integral calculation on the differential model of the geometric relationship in the plate straightening process to obtain a first calculation result: ； Among them, is the curvature of each point on the curve of the plate, is the projection coordinate of each point on the curve of the plate in the x direction, and are integration constants; Based on the first calculation result, determining the multi-roll straightening analytical model for each of the three types of regions.

8. The modeling method of the sheet straightening process according to claim 7, characterized in that, The process parameter information further includes the roll pitch between the geometric centers of two adjacent leveling rolls on the x-axis, the distance between the edge points of two adjacent leveling rolls on the z-axis, the roll radius of each leveling roll, the boundary conditions of the first set point, and the boundary conditions of the second set point; Based on the first calculation result, determining the multi-roll leveling analytical model for each of the three types of regions includes: For the entrance region, substituting the boundary conditions of the first set point into the first calculation result for calculation, and the second calculation result is: ； Combining the roll pitch between the geometric centers of two leveling rolls in the entrance region on the x-axis, the distance between the edge points of two adjacent leveling rolls in the entrance region on the z-axis, and the roll radius of the leveling rolls in the entrance region, substituting the boundary conditions of the second set point into the second calculation result for calculation, and the third calculation result is: ； Determining the third calculation result as the multi-roll leveling analytical model for the entrance region; Among them, is the distance between two adjacent contact points on the first straightening roll and the second straightening roll in the x-axis direction; is the acute angle between the line connecting the contact point on the first straightening roll and the geometric center and the z-axis; is the acute angle between the line connecting the contact point on the second straightening roll and the geometric center and the z-axis; is the inner integral variable; is the roll radius of the straightening roll; is the roll spacing between the geometric center of the first straightening roll and the geometric center of the second straightening roll in the x-axis direction; is the distance in the z-axis direction between the edge point on the side close to the sheet among the upper and lower edge points of the first straightening roll and the edge point on the side close to the sheet among the upper and lower edge points of the second straightening roll.

9. The modeling method of the sheet straightening process according to claim 7, characterized in that, Based on the first calculation result, determining the multi-roll leveling analytical model for each of the three types of regions includes: For the even formal region or the odd formal region, substituting the boundary conditions of the first set point into the first calculation result for calculation, and the fourth calculation result is obtained: ； Combining the roll pitch between the geometric centers of two leveling rolls in the even formal region or the odd formal region on the x-axis, the distance between the edge points of two adjacent leveling rolls in the even formal region or the odd formal region on the z-axis, and the roll radius of the leveling rolls in the even formal region or the odd formal region, substituting the boundary conditions of the second set point into the fourth calculation result for calculation, and the fifth calculation result is obtained: ； Determining the fifth calculation result as the multi-roll leveling analytical model for the even formal region or the odd formal region; Among them, is the distance between two adjacent contact points on the i-th straightening roll and the (i + 1)-th straightening roll in the x-axis direction; is the roll pitch between the geometric centers of the i-th straightening roll and the (i + 1)-th straightening roll in the x-axis direction; is the acute angle between the line connecting the contact point and the geometric center on the i-th straightening roll and the z-axis; is the acute angle between the line connecting the contact point and the geometric center on the (i + 1)-th straightening roll and the z-axis; is the distance between the edge point closer to the sheet on the upper and lower edge points of the i-th straightening roll and the edge point closer to the sheet on the upper and lower edge points of the (i + 1)-th straightening roll in the z-axis direction; is the roll radius of the straightening roll.

10. A modeling device for a sheet straightening process, characterized in that, Including: An acquisition module for acquiring the process information of the sheet leveling process; The process information at least includes zoning reference information and process parameter information; A partitioning module for partitioning the multi-roll leveling abstraction model into three types of regions based on the zoning reference information; the three types of regions include an entrance region, an even formal region, and an odd formal region; A first determination module for determining the differential model of the geometric relationship in the sheet leveling process for each of the three types of regions; A second determination module for determining the multi-roll leveling analytical model corresponding to the differential model of the geometric relationship in the sheet leveling process based on the process parameter information.

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