A glass curvature optimization method based on wiper requirements

Abstract

The present invention relates to a glass curvature optimization method based on wiper requirements. The method specifically comprises the following steps: S1: screening out unqualified points in each wiper trajectory curve; S2: dividing the glass curved surface into a glass curved surface G1 that does not require optimization and a glass curved surface G2 to be optimized; S3: determining boundary conditions for the glass curved surface G2 to be optimized; S4: establishing a cross-sectional curve model equation z=z(x) for the glass curved surface G2 to be optimized in any y-plane in the vehicle coordinate system based on the boundary conditions determined in S3; S5: constructing an optimized glass curved surface based on the established cross-sectional curve model equation z=z(x) for the glass curved surface G2 to be optimized in any y-plane, and repeating step S1 to perform curvature analysis to verify whether the design requirements are met. The present invention facilitates design adjustments for needle curvature changes.

Description

Technical Field

[0001] The present invention relates to the technical field of automobiles, and in particular to the technical field of automobile wiper systems. Background Art

[0002] The windshield wiper system is a critical component of a car. Windshield curvature is a key indicator of wiper system performance, including cleanliness, noise, and vibration. Therefore, during the vehicle design phase, the windshield curvature range and curvature variation rate are analyzed when designing the wiper system.

[0003] One prior art method discloses a car windshield curvature analysis method, which includes the following steps: 1. discretizing the wiper blade wiping area on the windshield; 2. extracting the curvature of the discrete points; 3. plotting the curvature coordinates of the discrete points; 4. establishing a mathematical model; 5. comparing the mathematical model with the original data; and 6. calculating the windshield curvature gradient. When applied, the method determines the windshield shape based on the specific vehicle type and target value, and determines reasonable curvature gradient requirements before development to meet the wiper blade and windshield fit requirements and ensure good wiper clearance and wiping performance of the wiper system. The disadvantage of this design method is that smart cars now have more extensive configurations, such as head-up displays, vehicle assistance systems, and rain sensors, all of which have design requirements for the curvature of the car glass. Furthermore, the glass boundary overlaps with the roof and A-pillars, which is closely related to the overall vehicle styling. Therefore, this method only designs the windshield's external surface based on the curvature requirements of the wiper, without considering the overall vehicle styling requirements and the curvature requirements of other components, resulting in an incomplete design.

[0004] The second prior art discloses a design method, system, and computer-readable storage medium for wiper system parameters. The design method comprises the following steps: analyzing glass parameters: based on glass data and regulations, preliminarily planning the wiping area, obtaining a preliminary wiper arm axis position, and analyzing glass curvature parameters; establishing axis parameters: based on the planned wiping area, setting the axis position near the planned axis position through parametric design; building a wiper model: inputting part parameters and using the obtained axis to build the wiper model; establishing a motion model: based on the wiper model, establishing a wiper motion model in CATIA software; after the axis position is determined, analyzing the wiper parameters based on the relevant parameters of the motion model, and adjusting and judging the glass curvature parameters and wiper parameters. This invention optimizes the parameters of the existing wiper's attack angle, blade acceleration, and connecting rod push angle, thereby improving wiper performance. While the steps include analyzing and judging criteria for glass parameters, it does not propose a design method for adjusting and optimizing glass curvature when the glass curvature does not meet wiper design requirements. Summary of the Invention

[0005] The purpose of the present invention is to provide a glass curvature optimization method based on wiper requirements to solve the problem that the existing technology does not take into account the vehicle styling requirements and the curvature requirements of other components.

[0006] In order to achieve the above object, the technical solution adopted by the present invention is as follows:

[0007] A glass curvature optimization method based on wiper requirements, the method specifically comprising:

[0008] S1: Based on the vehicle styling CAS data, the glass curvature is analyzed along the length of the wiper blade, and unqualified points are screened out for each wiper track curve. Unqualified points are points where the curvature radius along the length of the wiper blade is outside a preset range, or where the rate of change of the curvature radius along the length is less than a preset value.

[0009] S2: Connect all unqualified points to form a dividing line L0, dividing the glass surface into the glass surface G1 that does not need to be optimized and the glass surface G2 to be optimized;

[0010] S3: Determine the boundary conditions of the glass surface G2 to be optimized;

[0011] S4: In the vehicle coordinate system, based on the boundary conditions determined in S3, establish the cross-sectional curve model equation z=z(x) of the glass surface G2 to be optimized in any y plane;

[0012] S5: Based on the established cross-sectional curve model equation z=z(x) of the glass surface G2 to be optimized in any y-plane, perform parametric modeling to make the curve L_y0 in the y=0 plane and the curve L_wiper in the y-plane at the wiper working limit position d. Based on L0, L_y0, and L_wiper, make the optimized glass surface, and repeat step S1 for curvature analysis to verify whether it meets the design requirements.

[0013] Furthermore, the boundary conditions determined in S3 include at least the concave-convexity of the glass surface G2 to be optimized, the rate of change of the curvature radius of the glass surface G2 to be optimized, the continuity of the glass surfaces G1 and G2 at the dividing line L0, the boundary L1 of the scraping area in the surface G2, and the boundaries that affect the shape, such as the overlapping edge L2 between the glass and the ceiling, and the overlapping edge L3 between the glass and the A-pillar.

[0014] Furthermore, the boundary conditions are specifically as follows:

[0015] 1) Within the boundary L1 of the wiping area, the rate of change of the curvature radius of the wiper track curve does not exceed the preset value; outside the boundary L1, the curvature radius is allowed to change more than the preset value;

[0016] 2) The glass curved surface G1 that does not require optimization and the glass curved surface G2 to be optimized are both convex upward;

[0017] 3) Any point on the dividing line L0 has the same coordinates, the same curvature radius, and the same tangent slope in the glass curved surface G1 that does not need to be optimized and the glass curved surface G2 that is to be optimized;

[0018] 4) The positions of the overlapping edges L2 between the glass and the ceiling and L3 between the glass and the A-pillar remain unchanged, and the shapes remain the same as the original state.

[0019] Furthermore, the cross-sectional curve model equation z=z(x) of the glass curved surface G2 to be optimized in any y plane described in S4 is:

[0020]

[0021] In the formula

[0022] x0 is the x-axis coordinate value of the point on the dividing line L0, mm;

[0023] y0 is the y-axis coordinate value of the point on the dividing line L0, mm;

[0024] z0 is the z-axis coordinate value of the point on the dividing line L0, mm;

[0025] x2 is the x-axis coordinate value of the point on the boundary line L2, mm;

[0026] r0 is the radius of curvature at x=x0, mm

[0027] k is the slope at x = x0;

[0028] a is the target rate of change of the radius of curvature along the length of the curve;

[0029] a1 is the distance control factor, and the control model z = z(x) curve intersects the boundary L2 at x = x2;

[0030] n is the minimum curvature control factor, and 0≤n≤1;

[0031] r1 represents the radius of curvature when x=x1, mm;

[0032] k1 represents the slope of the tangent line when x=x1, mm;

[0033] x1 is the x-axis coordinate value of the point on the boundary line L1, mm;

[0034] z1 is the z-axis coordinate value when x=x1, in mm.

[0035] Furthermore, the method for creating the boundary L1 of the wiping area is: create a sketch in the y plane in CATIA, and project the main and auxiliary wiper tracks, which are the main wiper track projection boundary and the auxiliary wiper track projection boundary respectively, draw a straight line, straight line 1 is located outside the projection of the main wiper track projection boundary and the auxiliary wiper track projection boundary, and the minimum distance between the straight line and the boundary projection of the main wiper and auxiliary wiper is set at 2 to 10 mm, exit the sketch, create a plane perpendicular to the y plane based on the straight line, and make the intersection line of the plane and the glass, which is the boundary L1 of the wiping area.

[0036] Beneficial effects of the present invention:

[0037] When the curvature of the glass does not meet the design requirements of the wiper, the present invention proposes a design method for adjusting and optimizing the curvature radius of the glass, and establishes a model equation to obtain an accurate analytical solution. The change of the curvature radius is controllable, and through parametric modeling, the design adjustment of the curvature change is convenient. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] Figure 1 It is the curvature analysis optimization flow chart;

[0039] Figure 2 It is a schematic diagram of glass curvature range analysis;

[0040] Figure 3 It is a schematic diagram of the analysis of the rate of change of glass curvature;

[0041] Figure 4 It is a schematic diagram of surface area division;

[0042] Figure 5 It is a parameter construction diagram;

[0043] Figure 6 It is a schematic diagram of the rule definition of parameters;

[0044] Figure 7 It is a schematic diagram for establishing the equation rent;

[0045] Figure 8 It is a schematic diagram of the curve rules defined by the parametric model;

[0046] Figure 9 This is the effect diagram of the curvature radius change rate after optimization. DETAILED DESCRIPTION

[0047] The following will describe the implementation of the technical solution of the present invention with reference to the accompanying drawings and preferred embodiments. Those skilled in the art can easily understand other advantages and effects of the present invention from the contents disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments, and the details in this specification can also be modified or changed in various ways based on different viewpoints and applications without departing from the spirit of the present invention. It should be understood that the preferred embodiments are only for the purpose of illustrating the present invention and are not intended to limit the scope of protection of the present invention.

[0048] It should be noted that the illustrations provided in the following embodiments are merely schematic illustrations of the basic concept of the present invention. Therefore, the illustrations only show components related to the present invention and are not drawn according to the number, shape, and size of components in actual implementation. In actual implementation, the type, quantity, and proportion of each component may be changed arbitrarily, and the component layout may also be more complex.

[0049] The present invention provides a glass curvature analysis and optimization method. The analysis flow chart is shown in the attached Figure 1 , including the following steps:

[0050] Step S1: Glass curvature compliance analysis: Based on the vehicle styling CAS data, analyze the glass curvature along the length of the wiper blade to determine whether it meets the curvature requirements of the wiper system for the glass. If there are points where the curvature analysis does not meet the curvature radius range or curvature change rate requirements, these points are defined as unqualified points.

[0051] The wiper system requires that the curvature of the glass should be in the range of (Rmin~Rmax) mm in the length direction of the wiper, or the curvature radius change rate in the length direction should be less than |a0|. In this embodiment, (Rmin~Rmax) mm is defined as the preset range, and |a0| is the preset value.

[0052] The method for analyzing the glass curvature is to use an arrow-shaped curvature analysis tool in CATIA generative shape design to select and analyze the curvature of each scraping track curve.

[0053] like Figure 2 As shown, in the arrow-shaped curvature analysis tool, select the curve and use the wiper track curve length to analyze the curve curvature. Select "Chart." In the 2D chart, the Y axis represents the absolute value of the curvature radius, and the X axis represents the wiper track curve length. Use the maximum and minimum Y values ​​in the chart to determine whether the glass curvature range meets the design requirements.

[0054] like Figure 3 As shown, in the 2D chart, select the "All curves with the same origin" button, the Y-axis represents the cumulative change in the curvature radius, and according to the slope of the curve in the chart, determine whether the curvature change rate in the length direction of the wiper track meets the design requirements.

[0055] Step S2: Connect all unqualified points to form a segmentation line L0, segment the glass surface, and segment the glass surface into a glass surface G2 to be optimized and a glass surface G1 that does not need to be optimized.

[0056] Specifically, in the glass curvature analysis 2D chart, the X-axis coordinate represents the curve length, and the Y-axis represents the curvature radius value or the curvature change rate. According to the curvature analysis result of step S1, a 2D cursor is set to display in the 2D chart to display the X-axis value of the curvature unqualified point corresponding to each wiper trajectory curve. This X-axis value is the position of the unqualified point in the length direction of the wiper.

[0057] Based on the X-axis value of the failed point, a corresponding failed point is created on the wiper track curve in CATIA. The distance between the point and the curve is the X-axis value. The same method is used to determine the curvature of each remaining wiper track curve. The line connecting all the points forms the dividing line L0, which divides the glass surface into the glass surface to be optimized G2 and the glass surface that does not need to be optimized G1.

[0058] Step S3: Determine the boundary conditions of the glass surface G2 to be optimized, mainly including the convexity of the surface G2, the continuity of the glass surface G1 and the surface to be optimized G2 at the dividing line L0, the boundary L1 of the scraping area in the surface G2, and the boundaries that affect the shape, such as the overlap edge L2 between the glass and the ceiling, and the overlap edge L3 between the glass and the A-pillar.

[0059] Specifically, such as Figure 4 As shown, the boundary conditions are:

[0060] 1) Within the boundary L1 of the wiping area, the curvature radius change rate does not exceed |a0|, while outside the boundary L1, the curvature radius change is allowed to be greater than |a0|;

[0061] The method for creating the boundary L1 of the wiping area is as follows: Create a sketch in the y plane and project the main and auxiliary wiper tracks, which are the main wiper track projection boundary and the auxiliary wiper track projection boundary respectively. Draw a straight line, which is located outside the projection boundary of the main wiper track and the auxiliary wiper track projection boundary. The minimum distance between the straight line 1 and the projection boundary of the main wiper and auxiliary wiper is set to 2 to 10 mm. Exit the sketch, create a plane perpendicular to the y plane based on the straight line, and draw the intersection line between the plane and the glass, which is the boundary L1 of the wiping area. Figure 4 shown.

[0062] 2) The glass surfaces G1 and G2 should always maintain the same concavity and convexity, that is, the glass surfaces are all convex upwards;

[0063] 3) The dividing line L0 between the glass surfaces G1 and G2 should always remain continuous and smooth, with no sudden change in the radius of curvature. That is, any point on the dividing line L0 has the same coordinates, the same radius of curvature, and the same tangent slope in the surfaces G1 and G2.

[0064] 4) The positions of the overlapping edges L2 between the glass and the ceiling and L3 between the glass and the A-pillar should remain unchanged, and their shapes should be the same as the original state. That is, the optimized surface G2 should pass through L2 and L3.

[0065] Step S4: Model establishment and solution. Using the vehicle coordinate system as the coordinate system of the model equation, establish the curve equation z = z(x) in any y = y0 plane, the glass curvature radius r, the curve arc length s, and the curvature radius change rate a as follows:

[0066] Curvature radius calculation formula

[0067]

[0068] Arc length calculation formula

[0069]

[0070] The curvature radius change rate is modeled separately based on whether it is at the boundary L1 of the wiping area.

[0071] When x0≤x≤x1, within the boundary of the scraping area, the curvature radius change rate is established according to the target value to establish a differential equation model.

[0072]

[0073] When x1≤x≤x2, it is not within the boundary of the scraping area, and there is no requirement for the curvature change rate of the curve. Therefore, the following curvature radius attenuation model is constructed:

[0074]

[0075] In the formula

[0076] r(x) represents the radius of curvature, mm

[0077] r1 represents the radius of curvature when x=x1, mm

[0078] k1 represents the slope of the tangent line when x=x1, mm

[0079] z′ represents the first derivative of the curve equation z=z(x), that is, the slope

[0080] z″ represents the second derivative of the curve equation z=z(x)

[0081] x0 is the x-axis coordinate value of the point on the dividing line L0, mm;

[0082] x1 is the x-axis coordinate value of the point on the boundary line L1, mm;

[0083] s represents the arc length of the curve, mm

[0084] a is the target change rate control factor of the curvature radius within the wiping area boundary L1 along the length direction of the curve. A negative value of a indicates a decrease in curvature, and a positive value indicates an increase in curvature radius.

[0085] a1, n are the control factors for the rate of change of the curvature radius outside the wiping area boundary L1, and the control model z = z(x) curve intersects the boundary L2 at x = x2, and 0 ≤ n ≤ 1, a1 > 0;

[0086] Due to the different rates of change of curvature, two different model equations and curves are established according to different values ​​of x. The two model equation curves are continuous at x=x1, tangent continuous, and curvature continuous. According to the boundary condition analysis of step S3, the initial condition satisfied by the curve z=z(x) is

[0087]

[0088] In the formula

[0089] x0 is the x-axis coordinate value of the point on the dividing line L0, mm;

[0090] z0 is the z-axis coordinate value of the point on the dividing line L0, mm;

[0091] x2 is the x-axis coordinate value of the point on the boundary L2, mm;

[0092] z2 is the z-axis coordinate value of the point on the boundary L2, mm;

[0093] r0 is the radius of curvature at x=x0, mm

[0094] k is the slope at x = x0;

[0095] At the boundaries L0 and L1, x0≤x≤x1, from equations ①②③, we can get: The glass inclination angle changes slightly, so the slope k value at x0 is taken as the modeling parameter for z′, and the following differential equation is obtained:

[0096]

[0097] In the formula

[0098] k is the slope of z = z(x) at x0;

[0099] a is the target curvature radius change rate control factor

[0100] From formulas ①, ⑤, and ⑥, we can get

[0101] Model equation of the curve

[0102]

[0103] First derivative of the model equation of the curve

[0104]

[0105] Second derivative of the model equation of the curve

[0106]

[0107] In the formula

[0108] x0 is the x-axis coordinate value of the point on the dividing line L0, mm;

[0109] z0 is the z-axis coordinate value of the point on the dividing line L0, mm;

[0110] r0 is the radius of curvature at x=x0, mm

[0111] k is the slope at x = x0;

[0112] a is the target rate of change of the radius of curvature along the length of the curve;

[0113] z′ represents the first derivative of the curve equation z=z(x), that is, the slope

[0114] z″ represents the second derivative of the curve equation z=z(x)

[0115] On the surface between the boundaries L1 and L2, x1≤x≤x2, we can get from equations ① and ④:

[0116] Model equation of the curve

[0117]

[0118] First derivative of the model equation of the curve

[0119]

[0120] Second derivative of the model equation of the curve

[0121] z″(x)=-q[a1(x-x1) n +1]

[0122] In the formula

[0123] a1 is the control factor, and the control model z = z(x) curve intersects the boundary L2 at x = x2;

[0124] n is the minimum curvature control factor, and 0≤n≤1;

[0125] r1 represents the radius of curvature when x=x1, calculated by formula ①, mm

[0126] k1 represents the slope of the tangent line when x=x1, calculated by formula ⑧, mm

[0127] z′ represents the first derivative of the curve equation z=z(x), that is, the slope

[0128] z″ represents the second derivative of the curve equation z=z(x)

[0129] x1 is the x-axis coordinate value of the point on the boundary line L1, mm;

[0130] z1 is the z-axis coordinate value when x=x1, calculated by formula ⑦, mm;

[0131] Step S5: Surface parameterization and curvature analysis: Based on the established curve model equation, perform parametric modeling in CATIA to make the curve L_y0 in the y=0 plane and the curve L_wiper in the wiper working limit position plane. Based on the curves L0, L_y0, and L_wiper, make an optimized surface, and repeat step S1 for curvature analysis to verify whether it meets the design requirements.

[0132] In order to facilitate parametric modeling in CATIA, the parameter t is introduced, and 0≤t≤1, and the curve model equations ⑦ and ⑨ are converted into the following parametric equations, thereby obtaining the cross-sectional curve model equation z=z(x) of the glass surface G2 to be optimized in any y plane.

[0133] x=x0+(x2-x0)t

[0134] y=y0

[0135]

[0136] In the formula

[0137] x0 is the x-axis coordinate value of the point on the dividing line L0, mm;

[0138] y0 is the y-axis coordinate value of the point on the dividing line L0, mm;

[0139] z0 is the z-axis coordinate value of the point on the dividing line L0, mm;

[0140] x2 is the x-axis coordinate value of the point on the boundary line L2, mm;

[0141] r0 is the radius of curvature at x=x0, mm

[0142] k is the slope at x = x0;

[0143] a is the target rate of change of the radius of curvature along the length of the curve;

[0144] a1 is the distance control factor, and the control model z = z(x) curve intersects the boundary L2 at x = x2;

[0145] n is the minimum curvature control factor, and 0≤n≤1,

[0146] r1 represents the radius of curvature when x=x1, mm

[0147] k1 represents the slope of the tangent line when x=x1, mm

[0148] x1 is the x-axis coordinate value of the point on the boundary line L1, mm;

[0149] z1 is the z-axis coordinate value when x=x1, calculated by formula ⑦, mm;

[0150] Enter the CATIA Generative Shape Design workspace and draw and determine the boundaries required for the initial conditions. Create the intersection points (x0, y0, z0) between the y=0 plane and boundary L0, the intersection points (x2, y2, z2) between the y=0 plane and boundary L2, and the intersection line Ly0 between the y=0 plane and the glass surface G1. Create a tangent to the intersection line Ly0 at the intersection point (x0, y0, z0) within the y=0 plane.

[0151] Enter the Knowledge Engineering Consultant work platform, select the "f(x)" formula icon, and create Figure 5 The parameters shown, their meanings and types are as follows:

[0152] Table 1 Parameter creation

[0153]

[0154] Select the "Rule" rule, and in the "Rule editor", use the corresponding syntax and dictionary to write code and assign values ​​or formulas to each parameter, such as Figure 6 shown.

[0155] Select the (Set of Equations) icon to create a set of equations in the editor, such as Figure 7 As shown in the figure, set a1 as the unknown parameter and the other parameters as constant parameters, and solve for the value of a1.

[0156] Enter the Generative Shape Design Workbench, such as Figure 7-Figure 9As shown, select the curve from the equation in the wireframe toolbar, and create law curves for X, Y, and Z respectively according to the parametric equations. A curve L_y0 with curvature that meets the requirements will be created from these three law curves.

[0157] Repeat this step to create a curve L_wiper with the required curvature on the y-plane at the extreme position of the wiper area. In the Generative Shape Design workbench, select Multi-Section Surface, use the curves L_y0, L_wiper, and boundary L3 as sections, and use the split line L0 and boundary L2 as guide lines to create the optimized surface G2.

[0158] Repeat step S1 to analyze the glass curvature along the length of the wiper blade, such as Figure 9 As shown in Figure 1, the analysis effect diagram of the curvature radius change rate of the optimized curve is shown.

[0159] The above embodiments are only preferred embodiments for fully illustrating the present invention, and the protection scope of the present invention is not limited thereto. Any equivalent substitution or modification made by those skilled in the art based on the present invention is within the protection scope of the present invention.

Claims

1. A glass curvature optimization method based on wiper requirements, characterized by: The method is specifically as follows: S1: Based on the vehicle styling CAS data, the glass curvature is analyzed along the length of the wiper blade, and unqualified points are screened out for each wiper track curve. Unqualified points are points where the curvature radius along the length of the wiper blade is outside a preset range, or where the rate of change of the curvature radius along the length is less than a preset value. S2: Connect all unqualified points to form a dividing line L0, dividing the glass surface into the glass surface G1 that does not need to be optimized and the glass surface G2 to be optimized; S3: Determine the boundary conditions of the glass surface G2 to be optimized; S4: In the vehicle coordinate system, based on the boundary conditions determined in S3, establish the cross-sectional curve model equation z=z(x) of the glass surface G2 to be optimized in any y plane; S5: Based on the established cross-sectional curve model equation z=z(x) of the glass surface G2 to be optimized in any y-plane, perform parametric modeling to make the curve L_y0 in the y=0 plane and the curve L_wiper in the y-plane at the wiper working limit position d. Based on L0, L_y0, and L_wiper, make the optimized glass surface, and repeat step S1 for curvature analysis to verify whether it meets the design requirements.

2. The optimization method according to claim 1, wherein: The boundary conditions determined in S3 include at least the concave-convexity of the glass surface G2 to be optimized, the rate of change of the curvature radius of the glass surface G2 to be optimized, the continuity of the glass surfaces G1 and G2 at the dividing line L0, the boundary L1 of the scraping area in the surface G2, and the boundaries that affect the shape, including the overlapping edge L2 between the glass and the ceiling, and the overlapping edge L3 between the glass and the A-pillar.

3. The optimization method according to claim 2, wherein: The boundary conditions are specifically: 1) Within the boundary L1 of the wiping area, the rate of change of the curvature radius of the wiper track curve does not exceed the preset value; outside the boundary L1, the curvature radius is allowed to change more than the preset value; 2) The glass curved surface G1 that does not require optimization and the glass curved surface G2 to be optimized are both convex upward; 3) Any point on the dividing line L0 has the same coordinates, the same curvature radius, and the same tangent slope in the glass curved surface G1 that does not need to be optimized and the glass curved surface G2 that is to be optimized; 4) The positions of the overlapping edges L2 between the glass and the ceiling and L3 between the glass and the A-pillar remain unchanged, and the shapes remain the same as the original state.

4. The optimization method according to claim 3, wherein: The cross-sectional curve model equation z=z(x) of the glass curved surface G2 to be optimized in any y plane described in S4 is: In the formula x0 is the x-axis coordinate value of the point on the dividing line L0, mm; y0 is the y-axis coordinate value of the point on the dividing line L0, mm; z0 is the z-axis coordinate value of the point on the dividing line L0, mm; x2 is the x-axis coordinate value of the point on the boundary line L2, mm; r0 is the radius of curvature at x=x0, mm k is the slope at x = x0; a is the target rate of change of the radius of curvature along the length of the curve; a1 is the distance control factor, and the control model z = z(x) curve intersects the boundary L2 at x = x2; n is the minimum curvature control factor, and 0≤n≤1; r1 represents the radius of curvature when x=x1, mm; k1 represents the slope of the tangent line when x=x1; x1 is the x-axis coordinate value of the point on the boundary line L1, mm; z1 is the z-axis coordinate value when x=x1, in mm.

5. The optimization method according to claim 3, wherein: The method for creating the boundary L1 of the wiping area is: create a sketch in the y plane in CATIA, and project the main and auxiliary wiper tracks, which are the main wiper track projection boundary and the auxiliary wiper track projection boundary respectively, draw a straight line, the straight line is located outside the main wiper track projection boundary and the auxiliary wiper track projection boundary, and the minimum distance between the straight line and the main wiper and auxiliary wiper projection boundary is set at 2 to 10 mm, exit the sketch, create a plane perpendicular to the y plane based on the straight line, and make the intersection line of the plane and the glass, which is the boundary L1 of the wiping area.

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