A shear-thickening polishing and shaping method based on discretized mesh morphology evolution

Abstract

This application provides a shear-thickening polishing reshaping method based on discretized mesh morphology evolution, including the following steps: calculating the number of effective abrasive particles in a single layer participating in material removal based on polishing process parameters, polishing slurry composition, and polishing area characteristics, and converting it into a spatially localized mesh density; performing three-dimensional morphology measurement and digital discretization on the target workpiece surface, mapping the polishing action onto the discrete mesh of the workpiece surface; planning the scanning path of the polishing tool, dynamically simulating the evolution of the workpiece surface morphology during the polishing process; evaluating the workpiece surface morphology evolution results during the dynamic simulation, and if the morphology accuracy meets the requirements, extracting trajectory point data and feed rate data, uploading them to the shear-thickening polishing device for polishing. This invention transforms the global deconvolution problem into a localized mesh computation problem, thereby effectively improving the dwell time computation efficiency and constructing the workpiece surface morphology evolution process in shear-thickening deterministic polishing.

Description

Technical Field

[0001] This invention relates to the field of workpiece surface polishing technology, and specifically to a shear thickening polishing and shaping method based on the evolution of discretized mesh morphology. Background Technology

[0002] Shear-thickening polishing is widely used in the manufacturing of high-precision optical components, and its non-contact polishing, low manufacturing cost, and environmental friendliness have attracted widespread attention. With the development of high-precision instruments, the surface forming quality of optical components has received increasing attention, as the surface morphology accuracy directly determines the imaging accuracy and performance stability of the optical system. This presents a significant challenge to shear-thickening polishing technology.

[0003] In shear-thickening polishing, the cumulative effect of material removal leads to a continuously increasing amount of material removed from the workpiece as the tool tip moves at a constant speed along the polishing trajectory, further degrading the surface morphology accuracy. To obtain high-precision optical component surface morphology, the tool tip's moving speed is controlled during shear-thickening polishing to produce different amounts of material removal. This results in more material removal at locations with more material in the surface morphology, and less material removal at locations with less material. This process is called shear-thickening deterministic polishing. In deterministic polishing, convolution methods are often used to calculate the dwell time at polishing trajectory points, thereby obtaining a specific amount of material removed at any trajectory point as the tool tip moves along the polishing trajectory.

[0004] However, related technologies suggest that when the convolution kernel moves to the boundary region, the material removal portion exceeds the effective range of the topography matrix, leading to the convolution kernel going out of bounds at the boundary. At the same time, the convergence accuracy of deconvolution in calculating the dwell time is low. The main problems of related technologies are the convolution kernel going out of bounds and the high computational complexity of deconvolution in calculating the dwell time. Summary of the Invention

[0005] The purpose of this invention is to overcome the above-mentioned technical deficiencies and provide a shearing, thickening, polishing and shaping method based on the evolution of discretized mesh morphology, which solves the technical problem of high computational complexity in the prior art of convolution kernel over-boundary and inverse convolution to calculate dwell time.

[0006] To achieve the above-mentioned technical objectives, the present invention provides a shearing, thickening, polishing, and shaping method based on discretized mesh morphology evolution, comprising the following steps:

[0007] Based on polishing process parameters, polishing fluid composition and polishing area characteristics, the number of effective abrasive particles in a single layer participating in material removal is calculated and converted into spatially localized mesh density.

[0008] The surface of the target workpiece is subjected to three-dimensional morphological measurement and digital discretization, and the polishing effect is mapped onto the discrete mesh of the workpiece surface: an iterative mesh generation method is used to generate a discrete mesh that matches the number of effective abrasive grains in the single layer. The iterative process adjusts the mesh size to make the number of meshes approach the number of effective abrasive grains.

[0009] Plan the scanning path of the polishing tool, dynamically simulate the evolution of the workpiece surface morphology during the polishing process, and realize the visual evaluation of the polishing process;

[0010] The results of the workpiece surface morphology evolution during dynamic simulation are evaluated. If the morphology accuracy meets the requirements, the trajectory point data and feed speed data in the scanning path are extracted and converted into a machining trajectory file that can be recognized by the shearing thickening polishing device. The trajectory file is then uploaded to the shearing thickening polishing device for polishing.

[0011] Compared with the prior art, the beneficial effects of the present invention include:

[0012] This invention uses tool spindle speed, tool spindle power, tool radius, shear layer thickness, and polishing fluid parameters as input parameters. It evaluates surface shape accuracy through model simulation and adjusts the input parameters to obtain optimal process parameters. The generated trajectory file is then uploaded to a shear-thickening polishing device, ultimately correcting workpiece surface shape errors through shear-thickening polishing. This invention achieves discretization of the polishing process by establishing an effective abrasive grain mapping on the workpiece surface, transforming the global deconvolution problem into a localized mesh computation problem. This effectively improves the efficiency of dwell time calculation and accurately constructs the workpiece surface morphology evolution process in shear-thickening deterministic polishing, solving the high computational complexity of convolution kernel overshoot and deconvolution for dwell time calculation in existing technologies.

[0013] According to some embodiments of the present invention, the polishing process parameters include:

[0014] The polishing tool parameters, polishing fluid parameters, material removal coefficient, polishing trajectory spacing, workpiece size, and target morphology matrix are specified. The polishing tool parameters include: tool spindle speed, tool spindle power, tool radius, and shear layer thickness. The polishing fluid parameters include: viscosity index, consistency coefficient, initial liquid level height, polishing fluid volume, abrasive grain mass, abrasive grain size, and abrasive grain density, and base liquid particle mass, base liquid particle size, and base liquid density.

[0015] According to some embodiments of the present invention, the number of effective abrasive particles in a single layer participating in material removal is calculated and converted into a spatially localized mesh density, including the following steps:

[0016] The average mass of a single abrasive-base fluid cluster is calculated based on the abrasive particle size and density, and the base fluid particle size and density.

[0017] The total number of effective clusters simultaneously located within the polishing area is determined by the volume ratio method based on the polishing fluid volume, abrasive particle mass, base fluid particle mass, polishing area, shear layer thickness, and polishing fluid volume.

[0018] Considering the uniform distribution of abrasive grains within the shear layer, calculate the number of effective abrasive grains in a single layer that directly participate in the material peeling off the workpiece surface.

[0019] Based on the number of effective abrasive grains in a single layer, the macroscopic polishing fluid clusters in the polishing area are transformed into spatially localized mesh density.

[0020] According to some embodiments of the present invention, three-dimensional topography measurement and digital discretization of the target workpiece surface are performed, and the polishing effect is mapped onto a discrete mesh on the workpiece surface, including the following steps:

[0021] Import the 3D point cloud data of the workpiece surface to be processed, and perform coordinate normalization to obtain the workpiece size range and point cloud matrix;

[0022] Based on the number of effective abrasive particles in a single layer, an iterative mesh generation method is used to generate a discrete mesh that matches the number of particles. The iterative process adjusts the mesh size to make the number of meshes approach the number of effective abrasive particles. Each mesh represents a possible position of an effective abrasive particle on the workpiece surface.

[0023] By interpolating the discrete mesh with the surface point cloud matrix, a shape matrix matching the mesh division density is obtained.

[0024] According to some embodiments of the present invention, the scanning path of the polishing tool is planned, and the evolution of the workpiece surface morphology during the polishing process is dynamically simulated to achieve a visual evaluation of the polishing process, including the following steps:

[0025] Plan the trajectory matrix and target shape matrix covering the entire machining area on the workpiece surface;

[0026] Calculate the margin matrix from the topography matrix to the target topography matrix;

[0027] The simulation process is carried out in a time-step manner, moving gradually along the trajectory matrix until the maximum material allowance of the entire workpiece surface is lower than the set residual threshold or the predetermined number of simulation steps is reached. The simulation process records the surface height data of each time step simultaneously and finally outputs the evolution result of the workpiece surface morphology.

[0028] According to some embodiments of the present invention, planning the scanning path of a polishing tool includes the following steps:

[0029] Define the current trajectory point and the next trajectory point, and calculate the feed direction and feed distance of the current trajectory point;

[0030] Calculate the Euclidean distance from all the discrete meshes to the center of the current trajectory point, set the boundary of the polishing region, and enter the material removal simulation for all the discrete meshes within the boundary of the polishing region.

[0031] The fluid dynamic pressure within the polishing region is calculated and distributed into a discrete grid within the polishing region, thus decomposing the macroscopic fluid pressure into the microscopic abrasive grain pressure.

[0032] Based on the Preston equation, the material removal rate of each grid within the polishing area is calculated and assigned. Combining the material removal coefficient, the dynamic pressure of each grid and the relative speed between the tool and the workpiece, the material removal rate of each grid is calculated, and a mapping relationship between position, pressure and removal rate is established.

[0033] Find the grid index of the maximum material removal rate in the polishing area, then find the margin value in the margin matrix that matches the maximum value grid index, calculate the dwell time from the current trajectory point to the next trajectory point based on the matching margin value, and calculate the feed rate based on the feed distance and dwell time.

[0034] Set the simulation time step and timer. The time step is used to calculate the frequency of surface morphology evolution, and the timer is used to record the surface morphology evolution time of the trajectory segment from the current trajectory point to the next trajectory point, and to update the margin matrix and the position of the current trajectory point in real time.

[0035] According to some embodiments of the present invention, after evaluating the results of the workpiece surface morphology evolution during dynamic simulation, the method includes the following steps:

[0036] If the morphological accuracy does not meet the requirements, change the polishing process parameters and repeat the dynamic simulation process until the morphological accuracy meets the requirements.

[0037] According to some embodiments of the present invention, the dynamic simulation process includes the following steps:

[0038] Input the polishing process parameters into the input module of the simulation system;

[0039] The simulation program is run to simulate the evolution of surface morphology. The real-time monitoring module and image output module of the simulation system provide the real-time movement status of trajectory points and the real-time update status of surface morphology during the simulation process.

[0040] The output is a trajectory file that includes the coordinates of the trajectory points and the feed rate.

[0041] According to some embodiments of the present invention, after uploading the trajectory file to the shearing thickening polishing device, polishing is performed, including the following steps:

[0042] The surface morphology of the workpiece before polishing was measured using a laser interferometer to obtain the point cloud matrix;

[0043] Input the polishing process parameters into the simulation system for the evolution of surface morphology in shear-thickened polishing, and perform the simulation according to the simulation process;

[0044] The trajectory file, including the coordinates of the trajectory points and the feed speed, is obtained and uploaded to the shearing thickening and polishing device.

[0045] The shear-thickening polishing device is activated to perform deterministic polishing on the workpiece surface;

[0046] After running all the trajectory files, remove the polished workpiece;

[0047] A laser interferometer is used to measure and evaluate the surface morphology of the polished workpiece.

[0048] Additional aspects and advantages of the invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. Attached Figure Description

[0049] The above and / or additional aspects and advantages of the present invention will become apparent and readily understood from the description of the embodiments taken in conjunction with the following drawings, wherein the abstract drawings are to be completely consistent with one of the drawings in the specification:

[0050] Figure 1 This is a flowchart of the adaptive mesh generation module for effective abrasive grain mapping in an embodiment of the present invention;

[0051] Figure 2 This is a flowchart illustrating the process of establishing the discretized mesh surface morphology evolution module in an embodiment of the present invention.

[0052] Figure 3 This is a flowchart of the simulation system for the evolution of shear-thickening polished surface morphology in an embodiment of the present invention;

[0053] Figure 4 This is a schematic diagram of the shearing, thickening, and polishing device in an embodiment of the present invention;

[0054] Figure 5 These are comparison images of the workpiece surface morphology before and after polishing in an embodiment of the present invention;

[0055] Figure 6 This is a simulation result of the evolution of the surface morphology of the shear-thickened polished surface in an embodiment of the present invention;

[0056] Figure 7 This is a comparison diagram of the simulation results and the surface morphology of the workpiece after polishing in the embodiments of the present invention. Detailed Implementation

[0057] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention.

[0058] It should be noted that although functional modules are divided in the system diagram and the logical order is shown in the flowchart, in some cases, the steps shown or described may be performed in a different order than the module division in the system or the order in the flowchart. The terms "first," "second," etc., in the specification, claims, and the aforementioned drawings are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence.

[0059] Reference Figures 1-7 , Figure 1 This is a flowchart of the adaptive mesh generation module for effective abrasive grain mapping in an embodiment of the present invention; Figure 2 This is a flowchart illustrating the process of establishing the discretized mesh surface morphology evolution module in an embodiment of the present invention. Figure 3 This is a flowchart of the simulation system for the evolution of shear-thickening polished surface morphology in an embodiment of the present invention; Figure 4 This is a schematic diagram of the shearing, thickening, and polishing device in an embodiment of the present invention; Figure 5 These are comparison images of the surface morphology of the workpiece before and after polishing in an embodiment of the present invention, wherein (a) is a comparison of the surface morphology of workpiece w1 before and after polishing, and (b) is a comparison of the surface morphology of workpiece w2 before and after polishing. Figure 6 These are simulation results of the evolution of the surface morphology of shear-thickening polishing in the embodiments of the present invention, wherein (a) is the simulation result of workpiece w1 and (b) is the simulation result of workpiece w2. Figure 7 These are comparison diagrams of simulation results and polished workpiece surface morphology in the embodiments of the present invention. (a) is a comparison of simulation results and polished surface morphology of workpiece w1, and (b) is a comparison of simulation results and polished surface morphology of workpiece w2.

[0060] In some embodiments, the shear thickening polishing shaping method based on discretized mesh morphology evolution includes the following steps: 1) Calculating the number of effective abrasive particles in a single layer participating in material removal based on polishing process parameters, polishing fluid composition, and polishing area characteristics, and converting this number into a spatially localized mesh density; 2) Performing three-dimensional morphology measurement and digital discretization on the target workpiece surface, mapping the polishing action onto the discrete mesh of the workpiece surface; 3) Generating a discrete mesh matching the number of effective abrasive particles in a single layer using an iterative mesh generation method, with the iterative process adjusting the mesh size to make the mesh number approximate the effective abrasive particle number; 4) Planning the scanning path of the polishing tool, dynamically simulating the evolution of the workpiece surface morphology during the polishing process, and achieving a visual evaluation of the polishing process; 5) Evaluating the workpiece surface morphology evolution results during the dynamic simulation, and if the morphology accuracy meets the requirements, extracting the trajectory point data and feed rate data from the scanning path, converting them into a processing trajectory file recognizable by the shear thickening polishing device, and uploading the trajectory file to the shear thickening polishing device for polishing.

[0061] The specific technical solution is as follows:

[0062] A shearing thickening polishing and shaping method based on discretized mesh morphology evolution includes the following steps:

[0063] S1: Establish a polishing slurry discretization processing module to determine the number N of single-layer effective abrasive particles involved in material removal based on polishing process parameters, polishing slurry composition and polishing area characteristics.

[0064] First, based on the abrasive grain size d a and its density With base liquid particle size d c and its density First, calculate the average mass of a single abrasive-base fluid cluster. Second, based on the polishing fluid volume V... s Abrasive quality m at Mass of base liquid particles m ct The polishing area A, the shear layer thickness h0, and the polishing fluid volume V s The total number of effective clusters simultaneously located within the polishing region is determined using the volume ratio method. Then, considering the uniform distribution of abrasive grains within the shear layer, the number N of single-layer effective abrasive grains directly involved in material stripping from the workpiece surface is calculated. Finally, the macroscopic effective clusters of polishing slurry in the polishing region are transformed into spatially localized mesh density. ;

[0065] S2: An adaptive mesh generation module for effective abrasive grain mapping. The target workpiece surface undergoes 3D morphological measurement and digital discretization, thereby mapping the polishing process onto the discrete mesh.

[0066] First, import the 3D point cloud data of the workpiece surface and perform coordinate normalization to obtain the workpiece size range l.w With point cloud matrix Z p Secondly, based on the number of effective abrasive particles N in a single layer determined in step S1, an iterative mesh generation method is used to generate a discrete mesh that matches this number. The iterative process adjusts the mesh size to approximate the effective number of abrasive grains. Each mesh represents a possible point of action for an effective abrasive grain on the workpiece surface, thus ensuring the physical rationality of the force and removal rate distribution. Finally, combined with G... i,j With surface point cloud matrix Z p Perform interpolation to obtain the result. Matched topography matrix Z n ;

[0067] S3: Establish a discretized mesh surface morphology evolution module. Plan the scanning path of the polishing tool and perform dynamic evolution simulation of the workpiece surface morphology to achieve a visual evaluation of the polishing process.

[0068] First, plan a trajectory matrix covering the entire machining area on the workpiece surface. M represents the total number of trajectory points. Next, the topography matrix Z is calculated. n To the target topography matrix Z target residual matrix Finally, the simulation proceeds step-by-step along the trajectory matrix, continuously looping in a time-step manner until the maximum material allowance on the entire workpiece surface falls below the set residual threshold or the predetermined number of simulation steps is reached. The simulation process synchronously records the surface height data at each time step, ultimately outputting the evolution of the workpiece surface morphology.

[0069] For the t-th trajectory point:

[0070] a. The current trajectory point is denoted as The next trajectory point is denoted as Calculate the current trajectory point. The feed direction and feed distance;

[0071] b. Calculate all grids G i,j To the current trajectory point Euclidean distance of the center ,conform to The mesh is incorporated into the material removal simulation, R poly Represents the boundary of the polished area;

[0072] c. Calculate the hydrodynamic pressure P within the polishing area. d And the fluid dynamic pressure P d The mesh distributed within the polishing area decomposes macroscopic fluid pressure into microscopic abrasive grain pressure;

[0073] d. Calculate and assign the material removal rate for each grid within the polishing area according to the Preston equation. Combine this with the material removal coefficient k. s Dynamic pressure P of each grid d relative velocity v between tool and workpiece s Calculate the material removal rate for each grid and establish a mapping relationship between location, pressure, and removal rate;

[0074] e. Find the grid index of the maximum material removal rate within the polishing area. Then, find the remaining matrix. The value that matches the index is used to calculate the current trajectory point based on this margin. To the next trajectory point The dwell time. Furthermore, the feed rate is calculated based on the feed distance and dwell time;

[0075] f. Set the simulation time step d t With timer The time step is used to calculate the frequency of surface morphology evolution; the timer... Used for recording arrive The surface morphology evolution time of the trajectory segment is measured, and the residual matrix is ​​updated in real time. and the current trajectory point position ;

[0076] S4: Evaluate the workpiece surface morphology evolution results in S3. If the morphology accuracy meets the requirements, extract the trajectory point data and feed rate data in S3, convert them into a machining trajectory file that can be recognized by the shear thickening polishing device, and upload the trajectory file to the shear thickening polishing device for polishing; otherwise, change the polishing process parameters and repeat step S3.

[0077] Furthermore, the typical material removal model in S1 is denoted as... This indicates that the polishing tool is located in Material removal rate at the location. The calculation method for the polished area in S1 is as follows:

[0078] First, calculate the wall shear force on the polishing zone based on the tool shaft power and the flow velocity of the abrasive grains on the workpiece surface:

[0079]

[0080] In the formula, P is the tool axis power, v s The relative velocity between the tool and the workpiece is calculated as follows:

[0081]

[0082] In the formula, k s1 k s2 ks3 ω is the viscosity coefficient, which is related to the shear thickening properties of the polishing fluid. ω is the tool shaft rotation speed, R is the tool radius, and h0 is the shear layer thickness. Next, considering the non-Newtonian fluid characteristics of the polishing fluid, the shear stress within the shear layer is calculated based on its rheological model:

[0083]

[0084] In the formula, Viscosity With shear rate The relationship is derived by fitting data obtained from polishing fluid viscosity measurement experiments. Based on the definition of shear rate, the shear rate is obtained. The calculation formula:

[0085]

[0086] Finally, the polished area is calculated by combining the wall shear force and the fluid shear stress. In S1, the formula for calculating the number N of effective abrasive grains in a single layer participating in the material peeling off the workpiece surface is as follows:

[0087]

[0088] Based on this, the mesh density is obtained. :

[0089]

[0090] Furthermore, the iterative mesh generation method in S2 is as follows:

[0091] For the iteration step size d (k) The mesh generation expression is as follows:

[0092]

[0093] For step size d, the following adjustment rules apply:

[0094]

[0095] In the formula, N c This represents the number of sampling points in the polished area. When... When the time is right, it is considered convergent. This represents the error in the number of clusters.

[0096] Furthermore, in sub-step c of S3, the fluid dynamic pressure P is analyzed based on the two-dimensional steady-state Reynolds equation. d :

[0097]

[0098] In the formula, for steady-state conditions, V=0. In sub-step f of S3, the residual matrix... The calculation formula is as follows:

[0099]

[0100] In the formula, For the Boolean operation vector of the polished region, i.e. hour ,otherwise, .

[0101] Furthermore, based on steps S1 to S3 above, a simulation system for the evolution of surface morphology during shear-thickening polishing is established to allow operators to evaluate the surface morphology evolution results of workpieces with different combinations of polishing process parameters. The simulation system includes an input module for polishing process parameters, a real-time simulation status monitoring module, and an image output module. The simulation process is as follows: First, the polishing process parameters are input into the input module of the simulation system. Second, the simulation program is run to simulate the surface morphology evolution. Simultaneously, the real-time monitoring module and the image output module can provide real-time movement status of trajectory points and real-time updates of the surface morphology during the simulation process. Finally, a trajectory file including trajectory point coordinates and feed rate is output.

[0102] Furthermore, the shearing thickening polishing device includes: a gantry three-axis system 1, a workpiece fixture 2, a workpiece spindle system 3, an electrical control system 4, a polishing tank 5, and a polishing wheel 6. The gantry three-axis system 1 is rigidly fixed above a marble base, which contains the polishing tank 5 and the polishing wheel 6, thus forming the lower platform system. The workpiece fixture 2 is rigidly connected to the workpiece spindle system 3. The workpiece spindle system 3 is rigidly connected to the gantry three-axis system 1, and this system consists of a high-precision turntable, a servo motor, an ultrasonic generator, and a workpiece spindle. The electrical control system 4 has a multi-axis motion controller, a feedback interface, and an interactive interface, capable of uploading trajectory files and monitoring the operating status of the shearing thickening polishing device in real time.

[0103] Furthermore, the workpiece surface is polished using a shear-thickening polishing device, with the following steps:

[0104] The surface morphology of the workpiece before polishing was measured using a laser interferometer, and the point cloud matrix Z was obtained. p ;

[0105] Input polishing process parameters and perform simulation in the simulation system for the evolution of surface morphology of shear-thickened polished surfaces;

[0106] Obtain a trajectory file including trajectory point coordinates and feed speed, and upload it to the shearing thickening polishing device;

[0107] The measured workpiece is installed on the workpiece fixture 2, and polishing liquid is poured into the polishing tank 5;

[0108] The shear-thickening polishing device is started to perform deterministic polishing on the workpiece surface. After running all trajectory files, the polished workpiece is removed from workpiece fixture 2;

[0109] A laser interferometer is used to measure and evaluate the surface morphology of the polished workpiece.

[0110] In some embodiments, the shear thickening polishing and shaping method based on discretized mesh morphology evolution specifically includes the following steps: S1: Establish a polishing slurry discretization processing module, and define a set of polishing process parameters, including: polishing tool parameters (tool axis speed ω, tool axis power P, tool radius R, shear layer thickness h0), polishing slurry parameters (viscosity index) Consistency coefficient K, initial liquid level height H, polishing liquid volume V s Abrasive quality m at With abrasive particle size d a and abrasive density Mass of base liquid particles m ct With base liquid particle size d c and base liquid particle density Material removal coefficient k s Polishing trajectory spacing l s Workpiece dimensions l w Target topography matrix Z target The specific values ​​are shown in Table 1. Furthermore, based on the data in Table 1, the effective number of abrasive particles N in a single layer and the mesh density are calculated. The results are shown in Table 2.

[0111]

[0112]

[0113] S2: As Figure 1 As shown, an adaptive mesh generation module for effective abrasive grain mapping is established. The three-dimensional topography of the target workpiece surface is measured and digitally discretized, thereby mapping the polishing process onto the discrete mesh. First, the three-dimensional point cloud data of the workpiece surface is imported and coordinate normalization is performed to obtain the workpiece size range l. w =30mm and point cloud matrix Z p Secondly, based on the number of effective abrasive particles N in a single layer determined in step S1, an iterative mesh generation method is used to generate a discrete mesh that matches this number. The iterative process adjusts the mesh size to approximate the effective number of abrasive grains. Each mesh represents a possible point of action for an effective abrasive grain on the workpiece surface, thus ensuring the physical rationality of the force and removal rate distribution. Finally, combined with G...i,j With surface point cloud matrix Z p Perform interpolation to obtain the result. Matched topography matrix Z n Partial point cloud matrix Z p The data is shown in Table 3, with some discrete grids. The data is shown in Table 4, including the partial topography matrix Z. n The data is shown in Table 5;

[0114]

[0115]

[0116]

[0117] S3: As Figure 2 As shown, a discretized mesh surface morphology evolution module is established. The scanning path of the polishing tool is planned, and the dynamic evolution simulation of the workpiece surface morphology is performed to achieve a visual evaluation of the polishing process. First, a trajectory matrix covering the entire processing area is planned on the workpiece surface. M represents the total number of trajectory points. Next, the topography matrix Z is calculated. n To the target topography matrix Z target residual matrix Finally, the simulation proceeds step-by-step along the trajectory matrix, continuously looping in a time-step manner until the maximum material allowance on the entire workpiece surface falls below the set residual threshold, or the predetermined number of simulation steps is reached. The simulation process synchronously records the surface height data at each time step, ultimately outputting the evolution of the workpiece surface morphology. For the t-th trajectory point:

[0118] a. The current trajectory point is denoted as The next trajectory point is denoted as Calculate the current trajectory point. The feed direction and feed distance;

[0119] b. Calculate all grids G i,j To the current trajectory point Euclidean distance of the center ,conform to The mesh is incorporated into the material removal simulation, R poly Represents the boundary of the polished area;

[0120] c. Calculate the hydrodynamic pressure P within the polishing area. d And the fluid dynamic pressure P d The mesh distributed within the polishing area decomposes macroscopic fluid pressure into microscopic abrasive grain pressure;

[0121] d. Calculate and assign the material removal rate for each grid within the polishing area according to the Preston equation. Combine this with the material removal coefficient k. s Dynamic pressure P of each grid d relative velocity v between tool and workpiece s Calculate the material removal rate for each grid and establish a mapping relationship between location, pressure, and removal rate;

[0122] e. Find the grid index of the maximum material removal rate within the polishing area. Then, find the remaining matrix. The value that matches the index is used to calculate the current trajectory point based on this margin. To the next trajectory point The dwell time. Furthermore, the feed rate is calculated based on the feed distance and dwell time;

[0123] f. Set the simulation time step d t With timer The time step is used to calculate the frequency of surface morphology evolution; the timer... Used for recording arrive The surface morphology evolution time of the trajectory segment is measured, and the residual matrix is ​​updated in real time. and the current trajectory point position ;

[0124] S4: Evaluate the workpiece surface morphology evolution results in step S3. If the morphology accuracy meets the requirements, extract the trajectory point data and feed rate data from step S3, convert them into a machining trajectory file that can be recognized by the shear-thickening polishing device, and upload the trajectory file to the shear-thickening polishing device for polishing. Otherwise, change the polishing process parameters and repeat step S3. Table 1 of this embodiment provides polishing process parameters that meet the accuracy requirements, so step S3 is not repeated.

[0125] like Figure 3 As shown, this embodiment of the invention establishes a simulation system for the evolution of surface morphology during shear-thickening polishing, enabling operators to evaluate the surface morphology evolution results of workpieces with different combinations of polishing process parameters. The simulation system includes an input module for polishing process parameters, a real-time simulation status monitoring module, and an image output module. Its key feature is that, firstly, polishing process parameters are input into the input module of the simulation system. Secondly, the simulation program is run to simulate the surface morphology evolution. Simultaneously, the real-time monitoring module and the image output module provide real-time movement status of trajectory points and real-time updates of the surface morphology during the simulation process. Finally, a trajectory file including trajectory point coordinates and feed rate is output.

[0126] like Figure 4As shown, this embodiment of the invention proposes a shear-thickening polishing device, comprising: a gantry three-axis system 1, a workpiece fixture 2, a workpiece spindle system 3, an electrical control system 4, a polishing tank 5, and a polishing wheel 6. This embodiment of the invention performs shear-thickening deterministic polishing on a flat K9 glass surface, with the following steps:

[0127] S1: The surface morphology of the workpiece before polishing is measured using a laser interferometer to obtain the point cloud matrix Z. p The surface morphology of the workpiece before polishing is as follows: Figure 5 As shown;

[0128] S2: Input the polishing process parameters shown in Table 1 into the shear-thickening polishing surface morphology evolution simulation system and perform simulation. The simulation results are as follows: Figure 6 As shown. It should be noted that the simulation results output by the shear-thickening polishing surface morphology evolution simulation system are continuous surface morphology evolution animations with ".gif" as the suffix. In order to intuitively demonstrate the simulation results in the embodiments of this invention, only a few frames are selected for illustration.

[0129] S3: Obtain the trajectory file including the coordinates of the trajectory points and the feed speed, and upload it to the shearing thickening and polishing device;

[0130] S4: Install the workpiece measured in S1 onto the workpiece fixture 2, and pour polishing liquid into the polishing tank 5;

[0131] S5: Start the shearing thickening polishing device to perform deterministic polishing on the workpiece surface. After running all trajectory files, remove the polished workpiece from workpiece fixture 2;

[0132] S6: The surface morphology of the polished workpiece is measured and evaluated using a laser interferometer. The surface morphology of the polished workpiece is as follows: Figure 7 As shown.

[0133] To further compare the accuracy of the simulation results with the experimental results, the embodiments of the present invention calculated the surface accuracy before and after polishing and the simulation surface accuracy, and obtained the results shown in Table 6.

[0134]

[0135] Furthermore, one embodiment of the present invention provides a computer-readable storage medium storing computer-executable instructions that are executed by a processor or controller, for example, by a processor in the above-described terminal embodiment, such that the processor performs the shear-thickening polishing and shaping method based on discretized mesh morphology evolution in the above-described embodiment.

[0136] It will be understood by those skilled in the art that all or some of the steps and systems in the methods disclosed above can be implemented as software, firmware, hardware, and suitable combinations thereof. Some or all of the physical components can be implemented as software executed by a processor, such as a central processing unit, digital signal processor, or microprocessor, or as hardware, or as an integrated circuit, such as an application-specific integrated circuit. Such software can be distributed on a computer-readable medium, which can include computer storage media (or non-transitory media) and communication media (or transient media). As is known to those skilled in the art, the term computer storage media includes volatile and non-volatile, removable and non-removable media implemented in any method or technology for storing information (such as computer-readable instructions, data structures, program modules, or other data). Computer storage media includes, but is not limited to, RAM, ROM, EEPROM, flash memory or other memory technologies, CD-ROM, digital versatile disc (DVD) or other optical disc storage, magnetic cartridges, magnetic tape, disk storage or other magnetic storage devices, or any other medium that can be used to store desired information and is accessible to a computer. Furthermore, as is known to those skilled in the art, communication media typically contain computer-readable instructions, data structures, program modules, or other data in modulated data signals such as carrier waves or other transmission mechanisms, and may include any information delivery medium.

[0137] The above is a detailed description of the preferred embodiments of the present invention. However, the present invention is not limited to the above embodiments. Those skilled in the art can make various equivalent modifications or substitutions without departing from the spirit of the present invention. All such equivalent modifications or substitutions are included within the scope defined by the claims of the present invention.

[0138] The specific embodiments of the present invention described above do not constitute a limitation on the scope of protection of the present invention. Any other corresponding changes and modifications made in accordance with the technical concept of the present invention should be included within the scope of protection of the claims of the present invention.

Claims

1. A shearing, thickening, polishing, and shaping method based on discretized mesh morphology evolution, characterized in that, Including the following steps: Based on polishing process parameters, polishing fluid composition and polishing area characteristics, the number of effective abrasive particles in a single layer participating in material removal is calculated and converted into spatially localized mesh density. The surface of the target workpiece is subjected to three-dimensional morphological measurement and digital discretization, and the polishing effect is mapped onto the discrete mesh of the workpiece surface: an iterative mesh generation method is used to generate a discrete mesh that matches the number of effective abrasive grains in the single layer. The iterative process adjusts the mesh size to make the number of meshes approach the number of effective abrasive grains. Plan the scanning path of the polishing tool, dynamically simulate the evolution of the workpiece surface morphology during the polishing process, and realize the visual evaluation of the polishing process; The results of the workpiece surface morphology evolution during dynamic simulation are evaluated. If the morphology accuracy meets the requirements, the trajectory point data and feed speed data in the scanning path are extracted and converted into a machining trajectory file that can be recognized by the shearing thickening polishing device. The trajectory file is then uploaded to the shearing thickening polishing device for polishing.

2. The shearing, thickening, polishing, and shaping method based on discretized mesh morphology evolution according to claim 1, characterized in that, The polishing process parameters include: The polishing tool parameters, polishing fluid parameters, material removal coefficient, polishing trajectory spacing, workpiece size, and target morphology matrix are specified. The polishing tool parameters include: tool spindle speed, tool spindle power, tool radius, and shear layer thickness. The polishing fluid parameters include: viscosity index, consistency coefficient, initial liquid level height, polishing fluid volume, abrasive grain mass, abrasive grain size, and abrasive grain density, and base liquid particle mass, base liquid particle size, and base liquid density.

3. The shearing, thickening, polishing, and shaping method based on discretized mesh morphology evolution according to claim 2, characterized in that, The number of effective abrasive particles in a single layer participating in material removal is calculated and converted into a spatially localized mesh density, including the following steps: The average mass of a single abrasive-base fluid cluster is calculated based on the abrasive particle size and density, and the base fluid particle size and density. The total number of effective clusters simultaneously located within the polishing area is determined by the volume ratio method based on the polishing fluid volume, abrasive particle mass, base fluid particle mass, polishing area, shear layer thickness, and polishing fluid volume. Considering the uniform distribution of abrasive grains within the shear layer, calculate the number of effective abrasive grains in a single layer that directly participate in the material peeling off the workpiece surface. Based on the number of effective abrasive grains in a single layer, the macroscopic polishing fluid clusters in the polishing area are transformed into spatially localized mesh density.

4. The shearing, thickening, polishing, and shaping method based on discretized mesh morphology evolution according to claim 3, characterized in that, The process involves three-dimensional topography measurement and digital discretization of the target workpiece surface, mapping the polishing effect onto a discrete mesh on the workpiece surface, including the following steps: Import the 3D point cloud data of the workpiece surface to be processed, and perform coordinate normalization to obtain the workpiece size range and point cloud matrix; Based on the number of effective abrasive particles in a single layer, an iterative mesh generation method is used to generate a discrete mesh that matches the number of particles. The iterative process adjusts the mesh size to make the number of meshes approximate the number of effective abrasive particles. Each mesh represents a possible position of an effective abrasive particle on the workpiece surface. By interpolating the discrete mesh with the surface point cloud matrix, a shape matrix matching the mesh division density is obtained.

5. The shearing, thickening, polishing, and shaping method based on discretized mesh morphology evolution according to claim 4, characterized in that, The process involves planning the scanning path of the polishing tool, dynamically simulating the evolution of the workpiece surface morphology during the polishing process, and achieving a visual evaluation of the polishing process. This includes the following steps: Plan the trajectory matrix and target shape matrix covering the entire machining area on the workpiece surface; Calculate the margin matrix from the topography matrix to the target topography matrix; The simulation process is carried out in a time-step manner, moving gradually along the trajectory matrix until the maximum material allowance of the entire workpiece surface is lower than the set residual threshold or the predetermined number of simulation steps is reached. The simulation process records the surface height data of each time step simultaneously and finally outputs the evolution result of the workpiece surface morphology.

6. The shearing thickening polishing and shaping method based on discretized mesh morphology evolution according to claim 5, characterized in that, Planning the scanning path for the polishing tool includes the following steps: Define the current trajectory point and the next trajectory point, and calculate the feed direction and feed distance of the current trajectory point; Calculate the Euclidean distance from all the discrete meshes to the center of the current trajectory point, set the boundary of the polishing region, and enter the material removal simulation for all the discrete meshes within the boundary of the polishing region. The fluid dynamic pressure within the polishing region is calculated and distributed into a discrete grid within the polishing region, thus decomposing the macroscopic fluid pressure into the microscopic abrasive grain pressure. The material removal rate of each grid within the polishing area is calculated and assigned according to the Preston equation. Combining the material removal coefficient, the dynamic pressure of each grid and the relative speed between the tool and the workpiece, the material removal rate of each grid is calculated, and a mapping relationship between position, pressure and removal rate is established. Find the grid index of the maximum material removal rate in the polishing area, then find the margin value in the margin matrix that matches the maximum value grid index, calculate the dwell time from the current trajectory point to the next trajectory point based on the matching margin value, and calculate the feed rate based on the feed distance and dwell time. Set the simulation time step and timer. The time step is used to calculate the frequency of surface morphology evolution, and the timer is used to record the surface morphology evolution time of the trajectory segment from the current trajectory point to the next trajectory point, and to update the margin matrix and the position of the current trajectory point in real time.

7. The shearing thickening polishing and shaping method based on discretized mesh morphology evolution according to claim 6, characterized in that, After evaluating the workpiece surface morphology evolution results during dynamic simulation, the following steps are included: If the morphological accuracy does not meet the requirements, change the polishing process parameters and repeat the dynamic simulation process until the morphological accuracy meets the requirements.

8. The shearing thickening polishing and shaping method based on discretized mesh morphology evolution according to claim 7, characterized in that, The dynamic simulation process includes the following steps: Input the polishing process parameters into the input module of the simulation system; The simulation program is run to simulate the evolution of surface morphology. The real-time monitoring module and image output module of the simulation system provide the real-time movement status of trajectory points and the real-time update status of surface morphology during the simulation process. The output includes a trajectory file containing the coordinates of the trajectory points and the feed rate.

9. The shearing thickening polishing and shaping method based on discretized mesh morphology evolution according to claim 8, characterized in that, After uploading the trajectory file to the shearing, thickening, and polishing device, polishing is performed, including the following steps: The surface morphology of the workpiece before polishing was measured using a laser interferometer to obtain the point cloud matrix; Input the polishing process parameters into the simulation system for the evolution of surface morphology in shear-thickened polishing, and perform the simulation according to the simulation process; The trajectory file, including the coordinates of the trajectory points and the feed speed, is obtained and uploaded to the shearing, thickening, and polishing device. The shear-thickening polishing device is activated to perform deterministic polishing on the workpiece surface; After running all the trajectory files, remove the polished workpiece; A laser interferometer is used to measure and evaluate the surface morphology of the polished workpiece.

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