Composite material removal contour modeling method considering time-varying wear of abrasive paper
By establishing a contact force model between the flexible polishing disc and the workpiece and considering the time-varying nature of sandpaper wear, the problems of sandpaper wear and material removal depth variation during composite material polishing were solved, thus achieving high-precision machining of composite material workpieces.
Patent Information
- Application Number
- CN202511156201.5
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-08-19
- Publication Date
- 2025-11-28
AI Technical Summary
Existing technologies struggle to accurately predict the wear of sandpaper and changes in material removal depth during composite material polishing, leading to unstable processing quality. In particular, high precision in parameter control is difficult to achieve during robotic polishing.
A contact force model between the flexible polishing disc and the workpiece is established. Combining the Preston equation and considering the time-varying nature of sandpaper wear, key coefficients are calibrated through experiments, and a material removal profile model is constructed to predict the amount of material removed during the polishing process.
It improves the accuracy of composite material removal models, provides a comprehensive basis for the control of process parameters, and enhances the precision manufacturing level of composite material workpieces.
Smart Images
Figure CN121018534A_ABST
Abstract
Description
Technical Field
[0001] This invention belongs to the field of aerospace manufacturing engineering / aircraft assembly technology, and relates to a composite material removal contour modeling method that takes into account the time-varying wear of sandpaper. Background Technology
[0002] Composite materials possess excellent properties such as high strength, high modulus, low density, and low coefficient of thermal expansion, making them widely used in key components in the aerospace field. Although most composite materials are close to net-size forming, secondary processing is still required to achieve certain dimensional accuracy, shape accuracy, and surface quality to meet the needs of part assembly and application. Grinding and polishing, as a finishing process, is an effective means to achieve high dimensional accuracy surface treatment for composite material blanks. However, composite materials are typically difficult to machine, usually exhibiting high anisotropy and low interlaminar bond strength. In traditional grinding, the contact between the grinding wheel and the workpiece is rigid, which easily leads to over-cutting or under-cutting, causing stress concentration on the material surface and resulting in deformation of the workpiece after machining. Furthermore, increased stiffness exacerbates the interaction between the grinding wheel and the workpiece, making brittle materials prone to cracking, deteriorating surface quality, and reducing workpiece strength.
[0003] Robots are widely used in milling and polishing due to their flexibility and intelligence. Typically, robots are controlled with compliant mechanisms or equipped with compliant devices at the end effector for polishing operations. Flexible polishing, through more appropriate abrasive-workpiece interaction, better controls the material removal depth, achieving a more stable polishing process and improving surface quality. Robotic polishing involves multiple process parameters such as polishing pressure, spindle speed, and feed rate. A key challenge is how to comprehensively control these parameters to achieve a controllable removal rate while maintaining consistent processing quality. Furthermore, the high abrasiveness of the reinforcing components in composite materials leads to rapid wear of the sandpaper, causing changes in the material removal depth. Therefore, it is necessary to establish accurate material removal models to predict changes in the removal depth during polishing, providing a basis for the comprehensive control of process parameters. Summary of the Invention
[0004] This invention aims to overcome the shortcomings of existing technologies, improve the accuracy of composite material removal models, and provide a composite material removal contour modeling method that takes into account the time-varying wear of sandpaper. It involves robot integrated control technology, compliant control technology, path planning technology, robot grinding and polishing end technology, and contact force model technology. It has the characteristics of strong versatility and simple calculation process, which can realize accurate prediction of the changes in the composite material removal process, provide a reference for integrated control process parameters, and improve the precision manufacturing level of composite material workpieces.
[0005] The technical solution adopted in this invention is as follows:
[0006] A composite material removal profile modeling method considering time-varying abrasion of sandpaper is proposed. Based on the geometric contact characteristics between the flexible polishing disc and the composite material, the quantitative relationship between the deformation of the sponge layer of the polishing disc and the polishing pressure and angle is determined, establishing a contact force model between the flexible polishing disc and the workpiece. Key coefficients in the contact force model are calibrated based on contact deformation experiments. Combining the Preston equation, and considering the influence of sandpaper abrasion on the material removal process, the abrasion coefficient is expressed as a dynamic function changing with polishing time, constructing a material removal profile model. The method includes the following steps:
[0007] Step 1: Determine the deformation of the flexible polishing disc within the contact area.
[0008] Based on the contact condition between the flexible polishing disc and the workpiece, the geometry of the contact area is determined to be arc-shaped. A coordinate system is established with the opposite direction of the feed speed as the X-axis, the direction perpendicular to the feed speed as the Y-axis, and the direction perpendicular to the workpiece surface as the Z-axis. The deformation of the flexible polishing disc is analyzed, and the length d, width w, and compressive deformation h of the arc-shaped contact area are calculated.
[0009]
[0010] x0=l-h0tanθ (4)
[0011]
[0012] Where h(x,y) represents the amount of compression deformation at each point of the flexible polishing disc within the deformation area, d represents the length of the arc-shaped contact area, w represents the width of the arc-shaped contact area, according to Hertz contact theory, the flexible polishing disc is an elastic material, therefore the outer contour of the arc-shaped contact area is elliptical, l represents the major semi-axis of the elliptical outer contour of the contact area, R represents the radius of the polishing disc, θ represents the angle between the inclined polishing disc and the workpiece, h0 represents the maximum deformation depth of the flexible polishing disc, x0 represents the X-axis coordinate value of the location of the maximum deformation depth h0, and x1 represents the X-axis coordinate value of the corresponding location at the boundary of the contact area.
[0013] Step 2: Establish an equivalent model of contact force.
[0014] The contact force is modeled as a parallel connection of a linear spring and a damping element. Combining the fundamental principles of elasticity and materials mechanics, the stress distribution within the arc-shaped contact region is analyzed and calculated, and the distribution function of the contact stress within this region is derived. Integrating the local stress along the contact area yields the contact force model between the overall flexible polishing disc and the workpiece.
[0015]
[0016]
[0017] N1=(D-Kl)tanθ+Kh0(1+tan 2 θ) (8)
[0018] Where p(x,y) represents the distribution of contact stress, F a The contact force between the flexible polishing disc and the workpiece is represented by N1, a constant term, K, the contact stiffness coefficient, C, the contact damping coefficient, H, the thickness of the sponge layer of the flexible polishing disc, and y0, which represents the contact width value corresponding to position x0. max This represents half of the contact width w, and D represents the damping coefficient.
[0019] Step 3: Identification of contact force model coefficients.
[0020] By changing the grinding and polishing contact force and grinding and polishing inclination angle, a series of contact deformation experiments under different conditions were designed and carried out to solve the key coefficients in the contact force model.
[0021] Step 3.1: Based on the equipment's performance range, the grinding and polishing contact force is divided into three gradients: low, medium, and high. The tilt angle is set to three levels: small, medium, and large, forming a 3×3 full-factor experimental matrix. Each parameter combination is repeated three times to eliminate random errors. The division of the contact force gradient and tilt angle levels must cover the typical working range of the equipment, and the gradient and level intervals must be reasonable to effectively examine the impact of parameter changes on the results.
[0022] Step 3.2: Under static contact conditions, control the polishing disc to gradually press into the workpiece surface at a speed of 0.1 mm / s. When the contact force reaches the preset pressure threshold, maintain the position for 10 seconds and collect the average contact force data during the stable phase.
[0023] Step 3.3: Based on the experimentally measured dataset, use the contact force model formula, i.e., equation (7), to solve for the contact stiffness coefficient K and the damping coefficient D.
[0024] Step 4: Solve for the time-varying function of the Preston coefficients.
[0025] Based on the sandpaper wear state at different stages, a quantitative relationship between the Preston coefficient and the polishing time is established, and the Preston coefficient is expressed as a dynamic function that changes with polishing time.
[0026] Step 4.1: Set multiple sets of process parameters as needed, including polishing contact force, feed rate and grinding disc speed. Use sandpaper with a specific wear condition to perform a complete polishing test on a workpiece. During the test, the polishing pressure, feed rate and grinding disc speed must be kept constant.
[0027] Step 4.2: Before the experiment, use a Taylor profiler to obtain the initial profile height of the sampling point position on the workpiece surface along the vertical feed direction.
[0028] Step 4.3: After a single polishing cycle, measure the profile height of the sampling point along the vertical feed direction again, and obtain the material removal depth by calculating the difference at the lowest point of the profile.
[0029] Step 4.4: Based on the measured removal depth data, calculate the Preston coefficient k for the corresponding operating condition. p The trend of its change was fitted using a fifth-order polynomial.
[0030] Step 5: Create a material removal contour model.
[0031] A differential form material removal model is established based on the Preston equation. The model uses key parameters such as contact force and relative velocity to describe the amount of material removed per unit grinding and polishing path. The material removal profile model is obtained by integrating the amount of material removed per unit along the actual grinding and polishing path.
[0032]
[0033]
[0034] Among them, dh p k represents the removal depth at any point within the polishing area. p The Preston coefficient is represented by dl, the unit length by v(x,y), the relative linear velocity at any point by v(x,y), the material removal profile by MRD(y), the constant terms by N2 and N3, and the boundary of the contact area by f(y). f represents the feed speed of the grinding and polishing disc, and n represents the rotational speed of the grinding and polishing disc.
[0035] The beneficial effects of this invention are:
[0036] This invention integrates robot comprehensive control technology, compliant control technology, path planning technology, robot polishing end effector technology, and contact force model technology, overcoming the shortcomings of existing technologies and effectively improving the accuracy of composite material removal models. This method is characterized by its versatility and simple calculation process, accurately predicting changes in composite material removal, providing a basis for comprehensive control of process parameters, and possessing significant value for the precision manufacturing of composite material workpieces. Attached Figure Description
[0037] Figure 1 A flowchart of a composite material removal contour modeling method that takes into account time-varying abrasion of sandpaper;
[0038] Figure 2This diagram illustrates the contact process between the flexible polishing disc and the workpiece. The X-axis represents the opposite direction of the feed speed, the Y-axis is perpendicular to the feed speed direction, the Z-axis is vertically upward, the center point of the contact area is point O, d represents the length of the arc-shaped contact area, l represents the major axis of the outer contour of the contact area, R represents the radius of the polishing disc, θ represents the angle between the inclined polishing disc and the workpiece, h0 represents the maximum deformation depth, x0 represents the location of the maximum deformation depth h0, contour {A} represents the initial position of the polishing disc, and contour {B} represents the position of the polishing disc when it contacts the workpiece.
[0039] Figure 3(a) is a plan view of the contact area between the flexible polishing disc and the workpiece, where the outline {C} represents the straight boundary of the arc-shaped contact area, and x1 represents the corresponding position of the contact area boundary.
[0040] Figure 3(b) is a cross-sectional view of the contact between the flexible polishing disc and the workpiece, where H represents the thickness of the sponge layer of the flexible polishing disc.
[0041] Figure 4 This is a schematic diagram of the contact force model of a linear spring and a linear damping element connected in parallel, where dxdy represents the differential unit within the contact area;
[0042] Figure 5 This is a graph showing the variation of the Preston coefficient with polishing time.
[0043] Figure 6 A schematic diagram of the material removal contour model to take into account the time-varying wear of sandpaper. Detailed Implementation
[0044] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Those skilled in the art can easily understand other advantages and effects of the present invention from the content disclosed in this specification. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.
[0045] In most theoretical modeling processes, the classic Hertz elastic contact theory is commonly used to analyze the contact between the tool and the workpiece. However, when a robot uses a flexible grinding tool to process composite material workpieces, the large deformation caused by the contact between the flexible grinding tool and the workpiece renders the assumptions of elliptical contact area and small deformation in the Hertz elastic contact theory invalid. Furthermore, in conventional modeling, abrasive particles are usually assumed to be rigid bodies, and the effect of abrasive wear is not considered. However, composite materials differ from ordinary metallic materials; the high abrasiveness of their reinforcing components leads to rapid wear of the abrasive. These factors cause traditional material removal models to fail.
[0046] To address the aforementioned problems, this invention provides a composite material removal profile modeling method considering time-varying abrasion of sandpaper. This method determines the quantitative relationship between the deformation of the sponge layer of the polishing disc and the polishing pressure and angle based on the geometric contact characteristics between the flexible polishing disc and the composite workpiece. Based on contact deformation experiments, key coefficients in the contact force model are calibrated, establishing a distributed contact force model for the flexible polishing disc. Combining the Preston equation and considering the influence of sandpaper abrasion on the material removal process, the abrasion coefficient is expressed as a dynamic function changing with polishing time, constructing a material removal profile model. This method effectively improves the accuracy of the composite material removal model, predicts the material removal changes caused by sandpaper abrasion, provides a basis for the comprehensive control of process parameters, and has significant value for the precision manufacturing of composite workpieces.
[0047] This embodiment uses a feed rate v f =20mm / s, polishing pressure F n Taking the following working conditions as an example: =20N, polishing disc speed n=2500rpm, polishing angle θ=5°, the modeling process of the method of this invention is explained in detail. A composite material removal contour modeling method considering time-varying abrasion of sandpaper, the process is as follows: Figure 1 As shown, it includes the following steps:
[0048] Step 1: Determine the deformation of the flexible polishing disc within the contact area.
[0049] Based on the contact between the flexible polishing disc and the composite material workpiece, the geometry of the contact area is determined to be arc-shaped. A coordinate system is established with the opposite direction of the feed speed as the X-axis, the direction perpendicular to the feed speed as the Y-axis, and the direction perpendicular to the workpiece surface as the Z-axis. The deformation of the flexible polishing disc is analyzed, and the length d, width w, and compression deformation h of the arc-shaped contact area are solved.
[0050] Specifically, the contact process between the flexible polishing disc and the workpiece is as follows: Figure 2 As shown, contour {A} represents the initial position of the polishing disc, and contour {B} represents the position when the polishing disc contacts the workpiece. The center point of the contact area is point O. During the contact process between the inclined polishing disc and the workpiece, the sponge layer of the polishing disc is compressed and deformed. Since the upper surface of the workpiece is flat, the contact area between the two is arc-shaped. According to Hertz's contact theory, the flexible polishing disc is an elastic material, so the outer contour of the arc-shaped contact area is elliptical, as shown in Figure 3(a). The relationship between the contact length d, the contact width w, and the maximum deformation depth h0 of the arc-shaped area satisfies equations (1) and (2).
[0051] According to the cross-sectional view of the contact between the polishing disc and the workpiece, as shown in Figure 3(b), the outline {C} represents the straight boundary of the arc-shaped contact area, x1 represents the corresponding position of the contact area boundary, the position x0 of the maximum deformation depth h0 is obtained by equation (4), and the position x1 of the contact area boundary is obtained by equation (5).
[0052] The contact deformation between the inclined grinding disc and the workpiece is equal along the y-axis. Therefore, to solve for the deformation h(x, y) at each point of the flexible grinding disc in the contact area, it is only necessary to solve for the deformation h(x) at each point along the x-axis in the contact area. h(x, y) represents the difference between the profile of the grinding disc and the upper surface of the workpiece, obtained from equation (3).
[0053] Step 2: Establish an equivalent model of contact force.
[0054] The contact force is modeled as a parallel connection of a linear spring and a damping element. Combining the fundamental principles of elasticity and mechanics of materials, the stress distribution within the contact area is analyzed and calculated, and the distribution function of the contact stress within this area is derived. Integrating the local stress along the contact area yields the contact force model between the overall flexible polishing disc and the workpiece.
[0055] Specifically, the contact force between the grinding disc and the workpiece is equivalent to a model of a linear spring and a linear damping element connected in parallel, such as... Figure 4 As shown, the contact stress on the differential element within the contact region satisfies:
[0056] p(x,y)=Kδ+Dξ
[0057] δ represents the degree of deformation of the flexible polishing disc, expressed as:
[0058]
[0059] ξ is the relative normal contact velocity, expressed as:
[0060]
[0061] Therefore, the contact stress model between the flexible grinding disc and the workpiece is obtained from equation (6).
[0062] Integrating the local stress along the contact area, we obtain the contact force model between the flexible polishing disc and the workpiece as shown in equation (7).
[0063] Step 3: Identify the contact force model coefficients.
[0064] By changing the grinding and polishing pressure and the grinding and polishing inclination angle, a series of contact deformation experiments were designed and carried out under different conditions to solve the key coefficients in the contact force model.
[0065] Step 3.1: The end of the robot's force control device holds a flexible grinding disc and tilts it vertically downwards at a certain angle, gradually contacting the workpiece surface along the Z-direction. Based on the equipment's performance range, the grinding and polishing pressure is divided into three gradients: 20N, 30N, and 40N, with tilt angles set to three levels: 3°, 5°, and 7°, forming a 3×3 full-factor experimental matrix. Each parameter combination is repeated three times to eliminate random errors.
[0066] Step 3.2: Cover the workpiece surface with Fuji 5LW pressure film. When the polishing disc comes into contact with the workpiece, the pressure film will show color in the pressure-sensitive area, thus displaying the geometric outline of the contact area.
[0067] Under static contact conditions, the polishing disc is gradually pressed into the workpiece surface at a speed of 0.1 mm / s. When the contact force reaches the preset polishing pressure, the position is maintained for 10 seconds, and the average contact force data during the stable phase is collected.
[0068] Step 3.3: Measure the contact area to obtain the specific values of the contact length d and contact width w. Based on the measurement data, calculate the maximum deformation h0 under different polishing pressures and polishing angles. Using the contact force model formula, i.e., equation (7), solve for the stiffness coefficient K = 0.1078 and the damping coefficient D = 0.4135 in the contact force model.
[0069] Step 4: Solve for the time-varying function of the Preston coefficients.
[0070] Based on the sandpaper wear state at different stages, a quantitative relationship between the Preston coefficient and the polishing time is established, and the Preston coefficient is expressed as a dynamic function that changes with polishing time.
[0071] Step 4.1: Set multiple sets of process parameters as needed, including polishing contact force, feed rate and grinding disc speed. Use sandpaper with a specific wear condition to perform a complete polishing test on a workpiece. During the test, the polishing pressure, feed rate and grinding disc speed must be kept constant.
[0072] The experimental procedure is as follows: First, sandpaper with the selected wear condition is installed on the polishing equipment and the workpiece is installed on the worktable; then, the required polishing contact force, feed speed and rotation speed parameters are set; then, the polishing process is performed, and after the polishing is completed, the workpiece is removed for subsequent measurements.
[0073] Step 4.2: Before the experiment, use a Taylor profiler to obtain the initial profile height of the sampling point position on the workpiece surface along the vertical feed direction.
[0074] Step 4.3: After a single polishing cycle, measure the profile height of the sampling point along the vertical feed direction again, and obtain the material removal depth by calculating the difference at the lowest point of the profile.
[0075] Step 4.4: Based on the measured removal depth data, calculate the Preston coefficient k for the corresponding operating condition. p By fitting its changing trend using a 5th-order polynomial, the Preston coefficient k was obtained. p Regarding the curve of the change in polishing time, as follows: Figure 5 As shown.
[0076] Step 5: Create a material removal contour model.
[0077] A differential form material removal model is established based on the Preston equation. The model uses key parameters such as contact pressure and relative velocity to describe the amount of material removed per unit grinding and polishing path. The material removal profile model is obtained by integrating the amount of material removed per unit along the actual grinding and polishing path.
[0078] Specifically, the Preston equation is transformed into a differential form along the polishing path as shown in equation (9).
[0079] For any point on the grinding and polishing disc, its relative velocity is expressed as:
[0080]
[0081] The material removal profile model is obtained by integrating the unit material removal amount along the actual grinding and polishing path as shown in equations (10) to (12).
[0082] Using MATLAB to draw a schematic diagram of the material removal contour model, such as... Figure 6 As shown.
[0083] The above description is only a partial embodiment of the present invention and does not limit the implementation and protection scope of the present invention. Any improvements and modifications made by those skilled in the art based on the disclosure of the present invention without departing from the scope of the present invention should be within the protection scope of the present invention.
Claims
1. A method for contour modeling of composite material removal considering time-varying abrasion of sandpaper, characterized in that, Includes the following steps: Step 1: Determine the deformation of the flexible polishing disc within the contact area; Step 2: Establish an equivalent model of contact force; Step 3: Identification of contact force model coefficients; Step 4: Solve for the time-varying function of the Preston coefficients; Step 5: Create a material removal contour model.
2. The composite material removal contour modeling method considering time-varying abrasion of sandpaper according to claim 1, characterized in that, Step 1 specifically includes: Based on the contact condition between the flexible polishing disc and the workpiece, the geometry of the contact area is determined to be arc-shaped. A coordinate system is established with the opposite direction of the feed speed as the X-axis, the direction perpendicular to the feed speed as the Y-axis, and the direction perpendicular to the workpiece surface as the Z-axis. The deformation of the flexible polishing disc is analyzed, and the length d, width w, and compressive deformation h of the arc-shaped contact area are calculated. x0=l-h0 tanθ (4) Where h(x,y) represents the amount of compression deformation at each point of the flexible polishing disc within the deformation area, d represents the length of the arc-shaped contact area, w represents the width of the arc-shaped contact area, according to Hertz contact theory, the flexible polishing disc is an elastic material, therefore the outer contour of the arc-shaped contact area is elliptical, l represents the major semi-axis of the elliptical outer contour of the contact area, R represents the radius of the polishing disc, θ represents the angle between the inclined polishing disc and the workpiece, h0 represents the maximum deformation depth of the flexible polishing disc, x0 represents the X-axis coordinate value of the location of the maximum deformation depth h0, and x1 represents the X-axis coordinate value of the corresponding location at the boundary of the contact area.
3. The composite material removal contour modeling method considering time-varying abrasion of sandpaper according to claim 2, characterized in that, Step 2 specifically includes: The contact force is equivalent to a parallel model of a linear spring and a damping element. Combining the fundamental principles of elasticity and materials mechanics, the stress distribution within the arc-shaped contact region is analyzed and calculated, and the distribution function of the contact stress within this region is derived. Integrating the local stress along the contact area yields the contact force model between the overall flexible polishing disc and the workpiece. N1=(D-Kl)tanθ+Kh0(1+tan 2 θ) (8) Where p(x,y) represents the distribution of contact stress, F a The contact force between the flexible polishing disc and the workpiece is represented by N1, a constant term, K, the contact stiffness coefficient, C, the contact damping coefficient, H, the thickness of the sponge layer of the flexible polishing disc, and y0, which represents the contact width value corresponding to position x0. max This represents half of the contact width w, and D represents the damping coefficient.
4. The composite material removal contour modeling method considering time-varying abrasion of sandpaper according to claim 3, characterized in that, The contact stress on the differential element within the contact region satisfies: p(x,y)=Kδ+Dξ δ represents the degree of deformation of the flexible polishing disc, expressed as: ξ is the relative normal contact velocity, expressed as:
5. The composite material removal contour modeling method considering time-varying abrasion of sandpaper according to claim 3, characterized in that, Step 3 specifically includes: Step 3.1: Based on the equipment performance range, the grinding and polishing contact force is divided into three gradients: low, medium, and high, and the tilt angle is set to three levels: small, medium, and large, forming a 3×3 full factorial experimental matrix; Step 3.2: Under static contact conditions, control the polishing disc to gradually press into the workpiece surface at a speed of 0.1 mm / s; when the contact force reaches the preset pressure threshold, maintain the position for 10 seconds and collect the average contact force data during the stable phase; Step 3.3: Based on the experimentally measured dataset, use the contact force model formula, i.e., equation (7), to solve for the contact stiffness coefficient K and the damping coefficient D.
6. The composite material removal contour modeling method considering time-varying abrasion of sandpaper according to claim 5, characterized in that, In step 3.1, the division of contact force gradient and tilt angle must cover the typical working range of the equipment, and the gradient and horizontal intervals must be reasonable.
7. The composite material removal contour modeling method considering time-varying abrasion of sandpaper according to claim 5, characterized in that, In step 3.1, each parameter combination is repeated 3 times to eliminate random errors.
8. The composite material removal contour modeling method considering time-varying abrasion of sandpaper according to claim 5, characterized in that, Step 4 specifically includes: Step 4.1: Set multiple sets of process parameters as needed, including grinding and polishing contact force, feed rate and grinding disc speed, and use sandpaper with a specific wear condition to conduct a complete grinding and polishing experiment on a workpiece. Step 4.2: Before the experiment, obtain the initial contour height of the sampling point position on the workpiece surface along the vertical feed direction; Step 4.3: After a single polishing cycle, measure the profile height of the sampling point along the vertical feed direction again, and calculate the difference at the lowest point of the profile to obtain the material removal depth; Step 4.4: Based on the measured removal depth data, calculate the Preston coefficient k for the corresponding operating condition. p The trend of its change was fitted using a fifth-order polynomial.
9. A composite material removal contour modeling method considering time-varying abrasion of sandpaper according to claim 8, characterized in that, In step 4.1, the grinding and polishing pressure, feed rate and grinding disc speed must be kept constant during the experiment.
10. A composite material removal contour modeling method considering time-varying abrasion of sandpaper according to claim 8, characterized in that, Step 5 specifically includes: A differential form material removal model is established based on the Preston equation. The model uses key parameters to describe the amount of material removed per unit grinding and polishing path. The material removal profile model is obtained by integrating the amount of material removed per unit along the actual grinding and polishing path. Among them, dh p k represents the removal depth at any point within the polishing area. p The Preston coefficient is represented by dl, the unit length by v(x,y), the relative linear velocity at any point by v(x,y), the material removal profile by MRD(y), the constant terms by N2 and N3, and the boundary of the contact area by f(y). f represents the feed speed of the grinding and polishing disc, and n represents the rotational speed of the grinding and polishing disc.