Efficient batch grinding method of high spiral flute tap based on non-dominated sorting genetic algorithm

Abstract

The application provides a high-efficiency spiral flute tap batch grinding method based on a non-dominated sorting genetic algorithm (NSGA-II), which can accurately realize tap consistency grinding and improve efficiency. First, the wear and diameter change law of a forming grinding wheel is established based on an actual grinding condition; second, a forward calculation method improved based on an engagement principle is used to calculate a tap radial flute type according to a normal section type of the grinding wheel; then, the flute type corresponding to the grinding wheel in different wear and diameter states is calculated to establish the influence law of the grinding wheel wear on the flute type; the influence law of the grinding wheel wear on the flute type is verified through a grinding test and a Canny operator visual recognition; finally, the NSGA-II algorithm is used to optimize a grinding wheel clearance angle, eccentricity and inclination angle combination, and the accuracy of the algorithm is verified through a test. The application belongs to the field of mechanical engineering.

Description

Technical Field

[0001] This invention belongs to the field of mechanical engineering, and in particular relates to a method for mass grinding of spiral groove taps with high efficiency. Background Technology

[0002] Taps are the most important cutting tools for internal thread machining, and for small-diameter internal threads, they are even the only tool. For blind hole machining, spiral flute taps with top chip removal are mainly used. Their core geometry is the chip flute, which significantly affects their chip removal capacity, rigidity, cutting edge strength, cutting temperature, and cutting force. The chip flutes of spiral flute taps are ground using a profile grinding wheel, and their normal profile affects the radial flute profile, thus determining the tapping performance.

[0003] A prominent problem in the grinding process of spiral flute taps is the poor consistency of the taps during batch grinding due to wear and diameter changes of the forming grinding wheel, which affects the tapping performance. Therefore, this invention proposes an efficient batch grinding method for spiral flute taps. The chip groove calculation method and grinding wheel wear compensation method used in this invention are innovative aspects of this invention. Summary of the Invention

[0004] This invention aims to solve the problem of poor consistency in the batch grinding of spiral flute taps due to wear and diameter variations of the forming grinding wheel, which affects tapping performance. A highly efficient method for batch grinding of spiral flute taps is proposed, implemented through the following steps:

[0005] Step 1: Analysis of grinding wheel wear.

[0006] Step 2: Method for solving the tap groove shape.

[0007] Step 3: Analysis of the influence of grinding wheel wear on groove shape.

[0008] Step 4: Visual recognition verification.

[0009] Step 5: Compensation methods for grinding wheel wear.

[0010] Invention effects:

[0011] To ensure consistency in the batch grinding of spiral flute taps using a form grinding wheel, this paper proposes an efficient method for batch grinding of spiral flute taps. Taps are the most important internal thread cutting tools, widely used in various industrial fields. However, wear of the form grinding wheel affects the uniformity of grinding, thus impacting the tapping performance. Therefore, calculating the influence of form grinding wheel wear and diameter variation on the tap flute shape and providing a reasonable compensation method is an urgent problem to be solved. To address this issue, this invention proposes an efficient method for batch grinding of spiral flute taps. First, based on actual grinding production, the wear law of the forming grinding wheel is established, and its diameter change law is established according to the dressing cycle of the forming grinding wheel. Second, using a forward calculation method based on the meshing principle, the radial groove shape of the tap corresponding to the normal cross-section of the forming grinding wheel is calculated. Then, based on the forward calculation method, the radial groove shape of the tap corresponding to the forming grinding wheel with different wear states and different diameters is calculated, and the influence law of the forming grinding wheel wear and diameter change on the groove shape is established. Then, through grinding experiments, the taps corresponding to the forming grinding wheels with different wear states and diameters are ground, and the taps are cut at the standard section using a fast wire EDM machine. The influence law is verified using visual recognition technology based on the Canny operator. Finally, the non-dominated sorting genetic algorithm (NSGA-II) is used to find the optimal combination of grinding wheel clearance angle, eccentricity, and tilt angle for different wear and diameter states during the grinding process of the forming grinding wheel. The NSGA-II algorithm is verified by grinding experiments to verify the accuracy of the algorithm.

[0012] 1. Calculate the groove shape using a forward algorithm based on the meshing principle.

[0013] This study addresses the issue of the unpredictable impact of wear and diameter changes of forming grinding wheels on the groove shape during mass production. It proposes a forward calculation method based on the meshing principle to calculate the impact.

[0014] 2. A high-efficiency method for batch grinding of spiral groove taps can ensure consistent grinding of taps during batch grinding.

[0015] This study addresses the impact of wear and diameter changes of the forming grinding wheel on the groove shape during grinding. It proposes to use the Non-Dominated Sorting Genetic Algorithm (NSGA-II) to find the optimal combination of grinding wheel clearance angle and eccentricity tilt angle under different wear and diameter conditions during the grinding process. The NSGA-II algorithm is verified by grinding experiments. Attached Figure Description

[0016] Figure 1 Here is a flowchart of the visual recognition process based on the Canny operator;

[0017] Figure 2 This is a flowchart of the optimization process based on a non-dominated genetic algorithm. Detailed Implementation

[0018] To facilitate understanding by those skilled in the art, the present invention will be further described below with reference to embodiments. The content mentioned in the embodiments is not intended to limit the present invention.

[0019] Specific Implementation Method 1: A method for batch grinding of high-efficiency spiral groove taps includes the following steps:

[0020] Step 1: Analysis of grinding wheel wear.

[0021] Step 2: Method for solving the tap groove shape.

[0022] Step 3: Analysis of the influence of grinding wheel wear on groove shape.

[0023] Step 4: Visual recognition verification.

[0024] Step 5: Compensation methods for grinding wheel wear.

[0025] Specific Implementation Method Two: This implementation method differs from Specific Implementation Method One in that the specific operation for analyzing the wear of the grinding wheel in step one is as follows:

[0026] Analysis of the grinding wheel wear mechanism and inspection of the worn profile of the grinding wheel reveal that, during the grinding process, the wear pattern of the spiral groove within one grinding wheel dressing cycle can be approximated as circular arc wear. The formula for the circular arc wear model of the grinding wheel is as follows:

[0027]

[0028] In the formula: R(h) is the radius of gyration of the corresponding grinding wheel section, and h is the distance between the grinding wheel section and the end section.

[0029] R(h) can be expressed as:

[0030]

[0031] In the formula: 𝑅 W The diameter of the grinding wheel before wear is r, and the radius of the arc after wear is r. W This represents the thickness of the unworn portion of the grinding wheel.

[0032] To study the wear pattern of grinding wheels, the wear radius of the grinding wheel within one dressing cycle was statistically analyzed. The number of taps ground by the grinding wheel in one dressing cycle is X. Starting from the first tap, the wear radius r of the grinding wheel is measured once every x taps ground to obtain the wear radius of the grinding wheel at different stages. The wear of the grinding wheel is divided into two stages: rapid wear and stable wear.

[0033] The wear radius variation curve of the grinding wheel is similar to that of a general wear curve, both first experiencing an initial rapid wear stage and then entering a stable wear stage. Under the conditions of the above-mentioned grinding wheel, bar stock, and process parameters, an empirical model of the grinding wheel wear radius is established using a piecewise fitting method. The formula is as follows:

[0034]

[0035] In the formula: G is the number of grinding operations.

[0036] The other steps and parameters are the same as in Specific Implementation Method 1.

[0037] Specific Implementation Method Three: This implementation method differs from Specific Implementation Method One or Two in that the specific operations for the tap groove shape solution in Step Two and the influence of grinding wheel wear on the groove shape in Step Three are as follows:

[0038] Step 21: Based on the principle of spatial meshing, and using differential geometry theory and numerical analysis methods, a mathematical model of the spiral groove and the forming grinding wheel is established, and the contact line equation is derived:

[0039]

[0040] In the formula: u represents the geometric parameters of the generatrix forming the helical surface; The rotation angle parameter describes the degree of rotation of the rotor around its own axis. In practical applications, it represents the degree of rotation of the tap blank around its own axis; S is the shortest distance (center distance) between its axes. The angle between the axes is represented, which in this practical application represents the angle between the axis of the forming grinding wheel and the axis of the tap blank; p is the helical parameter, representing the distance the generatrix Г moves along the axial direction when it rotates around the z-axis by a unit angle.

[0041] Step 22: When machining the tap blank and forming the helical surface using the rotating surface of the forming grinding wheel, the forming grinding wheel rotates at high speed, and its cross-sectional profile forms a rotating surface. The tap blank rotates around its own axis and translates along the axis simultaneously, completing one lead of axial feed in one revolution. Assuming the rotating surface of the forming grinding wheel has been formed and the helical surface of the tap has been obtained through machining with the forming grinding wheel, at the instant of relative motion, there must be a tangent contact line between their surfaces. During machining, the rotating surface of the forming grinding wheel and the helical surface of the tap move along their own axes, and their spatial positions are relatively stationary; therefore, the position of the contact line remains unchanged in space. The contact line moves helically around the tap axis, ultimately forming the helical surface of the tap.

[0042] Coordinate system O; x, y, z is the coordinate system on the tap, where O is the center of the end section circle, the z-axis coincides with the axis of the tap blank, and the plane ox, y coincides with the end section of the tap blank. Coordinate system O; X, Y, Z is the coordinate system on the grinding wheel, where the Z-axis coincides with the axis of the grinding wheel, and the X-axis coincides with the x-axis but in opposite directions. The transformation relationship between the two coordinate systems is:

[0043]

[0044] Let the unit vectors in the x, y, and z directions of the coordinate axes be... , , The unit vectors in the X, Y, and Z directions of the coordinate axes are , , The radial vector of a point M in space relative to the two origins is:

[0045]

[0046]

[0047] In the formula: Let M be the radius vector from point M to point O; Let M be the radial vector from point M to point O.

[0048] The linear velocity of point M as it moves with the helical surface for:

[0049]

[0050] The linear velocity of point M as it moves with the grinding wheel for:

[0051]

[0052] Therefore, the relative velocity at point M for:

[0053]

[0054] In the formula: The angular velocity of the grinding wheel; ω is the angular velocity of the tap rotation.

[0055] At the contact point between the rotating surface and the helical surface, their relative velocity should be perpendicular to the common normal, i.e., the contact line condition is:

[0056]

[0057] In the formula: n is the common normal vector.

[0058] Equation (8) is the basic condition that the contact line between the surface of the forming grinding wheel and the chip groove of the tap should meet.

[0059] Given the rotating surface of the grinding wheel, by solving for the helical surface of the tap's chip groove, the normal n at any point can be obtained from the equation of the rotating surface. At this point:

[0060]

[0061] Therefore, the conditional equation for the contact line on the helical surface becomes:

[0062]

[0063] The geometric meaning of equation (9) is that if a radial vector T is drawn from the origin O of the grinding wheel coordinate system to a point on the helical surface, and T is coplanar with the normal n of that point and the axis k' of the grinding wheel, then that point is the contact point on the helical surface.

[0064] If the surface of the grinding wheel is known, and the spiral surface of the tap is to be determined, then the normal n at any point on it can be obtained according to the equation of the surface of revolution. In this case:

[0065]

[0066] Therefore, the contact line condition equation on the surface of revolution becomes:

[0067]

[0068] The geometric meaning of equation (10) is that if a radial vector t is drawn from the origin o of the tap coordinate system to a point on the rotating surface of the grinding wheel, and the linear velocity vector of that point when it makes a helical motion around the workpiece axis is perpendicular to the normal of the rotating surface at that point, then that point is the contact point on the rotating surface.

[0069] When grinding the chip groove of a tap with a profiled grinding wheel, it is necessary to set the equation of its rotating surface, such as... Figure 1 As shown in (c), let the equation of the rotating surface of the forming grinding wheel in the coordinate system O; X, Y, Z be:

[0070]

[0071] In the formula: R is a parameter variable, representing the radius of the tool rotation surface corresponding to Z, i.e. This is the equation for the axial profile of the cutting tool; is a parameter, representing the angle between the radius line R and the XOZ plane, with the direction from X to Y being positive.

[0072] Substituting equation (11) into coordinate transformation equation (2), we obtain the equation of the grinding wheel's rotating surface in the tap coordinate system o; x, y, z as follows:

[0073]

[0074] The three components of the normal vector at any point on the plane of revolution are:

[0075]

[0076] In the formula: for The derivative with respect to R.

[0077] The conditions for the contact line on the forming grinding wheel have been obtained above, as shown in equation (10). For ease of calculation, it is now converted into a coordinate representation and calculated using equation (14):

[0078]

[0079] Depend on Figure 1 (a) It can be known

[0080]

[0081] Therefore, it can be represented as:

[0082]

[0083] Conditional contact is:

[0084]

[0085] Substituting equation (13) into the equation and simplifying it, we get:

[0086]

[0087] This refers to the conditions that the two parameters R and p must satisfy at the contact point on the rotating surface of the grinding wheel.

[0088] like Figure 1 As shown in (d), in the taper coordinate system o; x, y, z, the vector equation of a space curve Г is:

[0089]

[0090] The coordinate form of the space curve Г is:

[0091]

[0092] Let curve Г rotate at a constant speed around the z-axis and simultaneously move at a constant speed along the z-axis, i.e., it undergoes helical motion. The trajectory surface it forms in space is a cylindrical helical surface with constant pitch, its axis being the z-axis, and Г being the generatrix of the helical surface. The equation of the helical surface is:

[0093]

[0094] Represented in coordinate form:

[0095]

[0096] In the formula: The parameter represents the angle through which the busbar rotates around the z-axis from its starting position. When viewed along the z-axis, clockwise rotation is positive.

[0097] By combining the contact line condition equation with the known equation of the grinding wheel's rotating surface, the contact line on the rotating surface can be obtained. By spiraling the contact line around the axis of the tap blank, the spiral surface of the tap can be obtained, and its equation is as follows:

[0098]

[0099] In the formula: R, , As a parameter variable, and R and Condition (18) should be satisfied.

[0100] Take the standard cross section The value of R can be obtained by solving the third equation of equation (23). The relationship, and then substitute it into and The formula can be used to calculate the expression for the standard cross-section groove of the tap.

[0101] Step 31: Based on the solution of the tap groove shape, establish a dressing model for grinding wheel wear and diameter change, and solve for its influence on the groove shape:

[0102] Since the wear transition arc appears and gradually increases, its cross-sectional equation is:

[0103]

[0104] In the formula: f2(R) is the transition arc. This is the equation expression for the normal section of the grinding wheel after wear.

[0105] According to equation (18), the contact condition for the wear profile can be obtained as follows:

[0106]

[0107] Therefore, the equation for the spiral surface of the spiral groove formed by grinding with a forming grinding wheel containing a transition arc is:

[0108]

[0109] Step 32: In the initial state, the mathematical equation for the chip groove of the tap ground by the forming grinding wheel is shown in equation (23). At this time, the equation of the center trajectory of the forming grinding wheel is:

[0110]

[0111] In the formula: (X) C Y C Z C () represents the center coordinates of the forming grinding wheel, and D0 represents the initial diameter of the forming grinding wheel.

[0112] Let the reduction in grinding wheel diameter after dressing be... At this point, the equation of the center trajectory of the grinding wheel is:

[0113]

[0114] The spiral groove is ground using a dressed shaped grinding wheel, and the equation of the ground spiral surface is:

[0115]

[0116] The other steps and parameters are the same as those in specific implementation methods one and two.

[0117] Specific Implementation Method Four: This implementation method differs from the previous three specific implementation methods in that the visual recognition verification operation in step four is as follows:

[0118] Step 41: Grind the tap using forming grinding wheels with different wear conditions and diameters. After the grinding test, use a fast wire EDM machine to cut the sample at the standard section to obtain the sample to be calibrated. Use a SANQTID industrial camera to photograph the standard section. Apply the Canny edge detection algorithm based on MATLAB software to process the original image taken by the industrial camera to obtain a binarized image with a clear radial profile of the chip groove.

[0119] First, a two-dimensional Gaussian filter is performed on the original cross-sectional image to obtain the image after noise removal. The expression for the two-dimensional Gaussian function is:

[0120]

[0121] In the formula: Here are the Gaussian filter parameters, and (x, y) are used to describe the cross-sectional surface image.

[0122] Solve for the gradient vector θ(x,y) and gradient magnitude H(x,y) of the cross-sectional image after Gaussian filtering to remove noise. Calculate the gradient magnitude components G of the cross-sectional image in the horizontal and vertical directions using a first-order difference operator. x and G y .

[0123]

[0124] The angle θ(x, y) ranges from [0°, -180] and is a multiple of 45°, that is:

[0125]

[0126] Step 42: Non-maximum suppression is used to remove non-edge information detected in the cross-sectional edge image, retaining the best edge information and highlighting the edge information of the cross-sectional contour image. Subsequently, a threshold is selected, and through thresholding, the gradient magnitude image is converted into a binary image to highlight the edge features of the cross-sectional contour.

[0127] The other steps and parameters are the same as those in the first three specific implementation methods.

[0128] Specific Implementation Method Five: This implementation method differs from the previous five in that the compensation method for grinding wheel wear in step five is specifically operated as follows:

[0129] Step 51: The Non-Dominated Sorting Genetic Algorithm (NSGA-II) is used to optimize the combination of key parameters in the grinding process. The optimization goal is to improve grinding consistency and efficiency, especially to address the impact of grinding wheel wear and diameter changes on the grinding effect. By rationally combining the grinding wheel clearance angle, eccentricity, and tilt angle, high efficiency and stability of the grinding process are achieved.

[0130] The primary objectives are to maximize grinding consistency and grinding efficiency. The objective functions are expressed as follows:

[0131]

[0132]

[0133] In the formula: f1 represents grinding consistency, f2 represents grinding efficiency, θ1 represents the grinding wheel clearance angle, E represents eccentricity, and θ2 represents the grinding wheel tilt angle.

[0134] Step 52: Generate an initial population, where each individual consists of three parameters: [θ1, E, θ2], representing the combination of grinding wheel parameters to be optimized. For each individual, calculate its performance on the objective function, obtaining the values ​​of f1 and f2. The dominance relationship of individuals is determined using the Pareto front. If individual A is not inferior to individual B on all objective functions and is superior to individual B on at least one objective function, then individual A is said to dominate individual B. Individuals are ranked according to their dominance relationships, forming multiple frontal levels to ensure optimal solutions are obtained under multi-objective optimization. The crowding degree of each individual is calculated; individuals with lower crowding degrees are closer to the Pareto front, ensuring a wider solution space is searched. Based on the non-dominated ranking and crowding degree, a tournament selection method is used to select high-quality individuals from the population. Crossover and mutation operations are performed using binary or real-number encoding to ensure population diversity and promote global search. A new generation of the population is generated through selection, crossover, and mutation operations, and multiple generations are iterated to update the population.

[0135] Step 53: Based on the optimization results, plot the Pareto front to show the trade-off between grinding consistency and grinding efficiency. By comparing the optimization effects of different objectives, select the parameter combination most suitable for practical applications; select the optimal solution from the Pareto front to ensure that the selected solution meets process requirements while improving grinding consistency and grinding efficiency.

[0136] Step 54: After multiple iterations, the optimal combination of grinding wheel clearance angle (θ1), eccentricity (E), and tilt angle (θ2) is finally obtained. This combination can effectively improve the stability and consistency of the grinding process, while also increasing grinding efficiency. Then, grinding experiments are designed to verify the accuracy of the non-dominated sorting genetic algorithm.

[0137] The other steps and parameters are the same as those in the previous five specific implementation methods.

[0138] It will be understood by those skilled in the art that, unless otherwise defined, all terms used herein (including technical and scientific terms) have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. It should also be understood that terms such as those defined in general dictionaries should be understood to have the same meaning as in the context of the prior art, and should not be interpreted in an idealized or overly formal sense unless specifically defined as herein.

[0139] It should be understood that the above detailed description of the technical solutions of the present invention with reference to preferred embodiments is illustrative and not restrictive. Those skilled in the art can modify the technical solutions described in the embodiments or make equivalent substitutions for some of the technical features based on reading this specification; however, these modifications or substitutions do not cause the essence of the corresponding technical solutions to depart from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for batch grinding of spiral groove taps based on a non-dominated sorting genetic algorithm, characterized in that, The efficient batch grinding method for spiral groove taps based on a non-dominated sorting genetic algorithm includes the following steps: Step 1: Grinding wheel wear analysis; Step 2: Method for solving the tap groove shape; Step 3: Analysis of the influence of grinding wheel wear on groove shape; Step 4: Visual recognition verification; Step 5: Compensation methods for grinding wheel wear.

2. The efficient batch grinding method for spiral groove taps based on a non-dominated sorting genetic algorithm according to claim 1, characterized in that, The specific steps for analyzing the wear of the grinding wheel in step one are as follows: Analysis of the grinding wheel wear mechanism and inspection of the worn profile of the grinding wheel reveal that, during the grinding process, the wear pattern of the spiral groove within the grinding wheel dressing cycle can be approximated as circular arc wear. The formula for the circular arc wear model of the grinding wheel is as follows: In the formula: R(h) is the radius of gyration of the corresponding grinding wheel section, and h is the distance between the grinding wheel section and the end section; R(h) can be expressed as: In the formula: 𝑅 W The diameter of the grinding wheel before wear is r, and the radius of the arc after wear is r. W The thickness of the unworn portion of the grinding wheel; To study the wear pattern of grinding wheels, the wear radius of the grinding wheel within one dressing cycle was statistically analyzed. The number of taps ground by the grinding wheel in one dressing cycle was X. Starting from the first tap, the wear radius r of the grinding wheel was measured once every x taps ground to obtain the wear radius of the grinding wheel at different stages. The wear of the grinding wheel was divided into two stages: rapid wear and stable wear. The wear radius variation curve of the grinding wheel is similar to that of a general wear curve, i.e., it first experiences an initial rapid wear stage and then enters a stable wear stage. Under the conditions of the above-mentioned grinding wheel, bar stock, and process parameters, an empirical model of the grinding wheel wear radius is established by a piecewise fitting method. The formula is as follows: In the formula: G is the number of grinding operations.

3. The efficient batch grinding method for spiral groove taps based on a non-dominated sorting genetic algorithm according to claim 2, characterized in that, The specific operation of the tap groove shape solution method in step two is as follows: Step 21: Based on the principle of spatial meshing, and using differential geometry theory and numerical analysis methods, establish a mathematical model of the spiral groove and the forming grinding wheel, and derive the contact line equation: Step 22: When machining the tap blank and forming the helical surface using the rotating surface of the forming grinding wheel, the forming grinding wheel rotates at high speed, and its cross-sectional profile forms a rotating surface; the tap blank rotates around its own axis and translates along the axis at the same time, completing one lead axial feed in one revolution; assuming that the rotating surface of the forming grinding wheel has been formed and the helical surface of the tap has been obtained by machining with the forming grinding wheel; at the instant of relative motion, there must be a tangent contact line between the two surfaces. During the machining process, the rotating surface of the forming grinding wheel and the helical surface of the tap move along their own axes respectively, and their spatial positions are relatively stationary, so the position of the contact line remains unchanged in space; the contact line moves helically around the tap axis, eventually forming the helical surface of the tap.

4. The efficient batch grinding method for spiral groove taps based on a non-dominated sorting genetic algorithm according to claim 3, characterized in that, The specific steps for analyzing the influence of grinding wheel wear on the groove shape in step three are as follows: Step 31: Based on the solution of the tap groove shape, establish a dressing model for grinding wheel wear and diameter change, and solve for its influence on the groove shape: Since the wear transition arc appears and gradually increases, its cross-sectional equation is: In the formula: f2(R) is the transition arc. The equation for the normal section of the grinding wheel after wear is given. The contact condition formula for the wear profile can be obtained as follows: Therefore, the equation for the spiral surface of the spiral groove formed by grinding with a forming grinding wheel containing a transition arc is: Step 32: The equation of the center trajectory of the forming grinding wheel after the diameter changes is: In the formula: (X) C Y C Z C D0 is the initial diameter of the forming grinding wheel, where D is the center coordinate of the forming grinding wheel. Let the reduction in grinding wheel diameter after dressing be... At this point, the equation of the center trajectory of the grinding wheel is: The spiral groove is ground using a dressed shaped grinding wheel, and the equation of the ground spiral surface is: （9）。 5. The efficient batch grinding method for spiral groove taps based on a non-dominated sorting genetic algorithm according to claim 4, characterized in that, The visual recognition verification in step four is specifically performed as follows: Step 41: Grind the tap using shaped grinding wheels with different wear conditions and diameters. After the grinding test, cut the sample at the standard section using a fast wire EDM machine to obtain the sample to be calibrated. Take pictures of the standard section using a SANQTID industrial camera. Apply the Canny edge detection algorithm based on MATLAB software to process the original image taken by the industrial camera to obtain a binarized image with a clear radial section outline of the chip groove. First, a two-dimensional Gaussian filter is performed on the original cross-sectional image to obtain the image after noise removal. The expression for the two-dimensional Gaussian function is: In the formula: Here are the Gaussian filter parameters, and (x, y) is used to describe the cross-sectional surface image. Solve for the gradient vector θ(x,y) and gradient magnitude H(x,y) of the cross-sectional image after Gaussian filtering to remove noise. Calculate the gradient magnitude components G of the cross-sectional image in the horizontal and vertical directions using a first-order difference operator. x and G y ; The angle θ(x, y) ranges from [0°, -180] and is a multiple of 45°, that is: Step 42: Non-edge information detected in the cross-sectional edge image is removed by non-maximum suppression, leaving the best edge information to highlight the edge information of the cross-sectional contour image; then, a threshold is selected, and the gradient magnitude image is converted into a binary image through thresholding to highlight the edge features of the cross-sectional contour.

6. The efficient batch grinding method for spiral groove taps based on a non-dominated sorting genetic algorithm according to claim 5, characterized in that, The specific operation of the grinding wheel wear compensation method in step five is as follows: Step 51: The non-dominated sorting genetic algorithm is used to optimize the combination of key parameters in the grinding process. The optimization goal is to improve grinding consistency and grinding efficiency, especially to address the impact of grinding wheel wear and diameter changes on the grinding effect. By reasonably combining the grinding wheel clearance angle, eccentricity, and tilt angle, the grinding process can be made efficient and stable. Step 52: Generate an initial population, where each individual consists of three parameters: [θ1, E, θ2], representing the combination of grinding wheel parameters to be optimized. For each individual, calculate its performance on the objective function, obtaining f1 and f2, which are the values ​​of grinding consistency and grinding efficiency. Determine the dominance relationship of individuals through the Pareto front. If individual A is not inferior to individual B on all objective functions and is superior to individual B on at least one objective function, then individual A is said to dominate individual B. Sort the individuals according to the dominance relationship to form multiple front levels, ensuring that the optimal solution is obtained under multi-objective optimization. Calculate the crowding degree of each individual. Individuals with lower crowding degree are closer to the Pareto front, ensuring that a wider solution space is searched. Based on the non-dominated sorting and crowding degree, a tournament selection method is used to select high-quality individuals from the population. Use binary or real number encoding to perform crossover and mutation operations to ensure population diversity and promote global search. Generate a new generation of population through selection, crossover, and mutation operations, perform multiple generations of iteration, and update the population. Step 53: Based on the optimization results, draw the Pareto front plot to show the trade-off between grinding consistency and grinding efficiency; by comparing the optimization effects of different objectives, select the parameter combination most suitable for practical applications; select the optimal solution from the Pareto front to ensure that the selected solution meets the process requirements while improving grinding consistency and grinding efficiency. Step 54: After multiple iterations, the optimal combination of grinding wheel clearance angle (θ1), eccentricity (E), and tilt angle (θ2) is finally obtained. This combination can effectively improve the stability and consistency of the grinding process, while also increasing grinding efficiency.

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