Method and system for generating curved surface machining path for ultra-precision diamond lathe

Abstract

The present invention relates to a method and system for generating a curved surface machining path for an ultra-precision diamond lathe, which mainly obtains three-dimensional point cloud data of a surface to be machined through a three-dimensional scanning device, performs global curvature calculation, and divides the surface into multiple sub-areas to generate an initial machining path. Subsequently, the initial path is optimized to reduce interference and errors, and finally a fully verified target machining path is obtained. This path is imported into a lathe for machining to achieve high-precision curved surface machining. The method improves machining accuracy and surface quality, ensuring higher finish and shape accuracy in ultra-precision machining.

Description

Technical Field

[0001] The invention relates to the technical field of data processing, and in particular to a method and system for generating a curved surface machining path of an ultra-precision diamond lathe. Background Art

[0002] In the fields of aerospace, optical devices and precision instruments, the processing quality of complex curved surfaces directly affects the performance and reliability of products. Traditional processing path generation methods are often based on the simple extraction of geometric features. Although they can meet certain processing accuracy requirements, they are prone to accumulate processing errors when faced with more complex curved shapes, thus affecting the final surface quality.

[0003] As the complexity of surface processing requirements increases, existing path generation algorithms have exposed obvious deficiencies in surface continuity, smoothness, and processing efficiency. For example, when processing free-form surfaces, traditional path generation methods often have difficulty ensuring the uniformity of tool trajectories and the stability of the processing process, resulting in ripples or uneven roughness on the surface. This situation is particularly prominent in ultra-precision machining, because even small trajectory deviations can have a significant impact on surface quality.

[0004] There is currently no solution to this technical problem. Summary of the invention

[0005] The main purpose of the present invention is to provide a method and system for generating a curved surface machining path for an ultra-precision diamond lathe, so as to solve the technical problem that the existing path generation algorithm has obvious deficiencies in curved surface continuity, smoothness and machining efficiency.

[0006] To achieve the above-mentioned purpose, the present invention provides a method for generating a surface machining path of an ultra-precision diamond lathe, characterized in that it includes the following steps: scanning and processing the surface to be machined based on a three-dimensional scanning device to obtain three-dimensional point cloud data of the surface to be machined; performing global curvature calculation based on the three-dimensional point cloud data, and dividing the surface to be machined into multiple surface sub-areas based on the calculation results; generating corresponding initial machining paths for the multiple surface sub-areas respectively, and optimizing the initial machining paths of the multiple surface sub-areas to obtain a target machining path; comprehensively verifying the target machining path, and when the target machining path passes the comprehensive verification, importing the target machining path into the ultra-precision diamond lathe for machining execution.

[0007] Optionally, after scanning the surface to be processed based on a three-dimensional scanning device to obtain three-dimensional point cloud data of the surface to be processed, the surface processing path generation method also includes: calculating the neighborhood average value of each data point in the three-dimensional point cloud data, identifying target data points whose neighborhood average value is higher than a first preset threshold, and eliminating the target data points in the three-dimensional point cloud data to obtain first three-dimensional point cloud data; dividing the point cloud in the first three-dimensional point cloud data into equally spaced voxel grids, retaining point clouds of a second preset threshold in each grid, and performing group processing on the point clouds retained in each grid to obtain second three-dimensional point cloud data; using a rigid transformation algorithm to transform the second three-dimensional point cloud data into the ultra-precision In the processing coordinate system of a dense diamond lathe, and in the process of the rigid transformation algorithm transforming the second three-dimensional point cloud data, the transformation parameters of the rigid transformation algorithm are adjusted by an iterative nearest point algorithm until the coordinate alignment error of the second three-dimensional point cloud data transformed by the rigid transformation algorithm is lower than a third threshold value, so as to obtain third three-dimensional point cloud data; multiple point clouds are selected as first control points in the third three-dimensional point cloud data, and a NURBS surface model is constructed based on the first control points, and the position of the first control point in the NURBS surface model is adjusted by using a least squares method, so that the NURBS surface model is close to the third three-dimensional point cloud data, so as to obtain a target surface model.

[0008] Optionally, a global curvature calculation is performed based on the three-dimensional point cloud data, and the surface to be processed is divided into multiple surface sub-areas based on the calculation results, including: calculating the normal vector and tangent vector of the target surface model at each point, and solving the surface parameter equation of the target surface model based on the normal vector and tangent vector to obtain curvature data, wherein the curvature data at least includes: principal curvature, Gaussian curvature and mean curvature; constructing a global curvature field of the target surface model based on the curvature data, wherein the global curvature field is a contour map or a heat map; based on the global curvature field, dividing the target surface model into multiple initial surface sub-areas, wherein different initial surface sub-areas correspond to different curvature ranges; determining the intersection area between the multiple initial surface sub-areas, and introducing a transition area in the multiple initial surface sub-areas based on the curvature data corresponding to the intersection area in the global curvature field, to obtain a final multiple surface sub-areas.

[0009] Optionally, corresponding initial processing paths are generated for the multiple surface sub-regions, respectively, including: based on the curvature ranges of the multiple surface sub-regions, dividing the multiple surface sub-regions into a first type of surface sub-regions and a second type of surface sub-regions, wherein the curvature range corresponding to the first type of surface sub-regions is higher than the curvature range corresponding to the second type of surface sub-regions; using a contour following method to perform path generation processing on the second type of surface sub-regions to obtain initial processing paths corresponding to the second type of surface sub-regions; using a parallel cutting method to perform path generation processing on the first type of surface sub-regions to obtain initial processing paths corresponding to the first type of surface sub-regions.

[0010] Optionally, the initial processing paths of the multiple surface sub-areas are optimized to obtain a target processing path, including: simulating the motion trajectory of the initial processing paths of the multiple surface sub-areas during the processing, identifying the interference data between the tool and the workpiece during the simulation process, and adjusting the initial processing path based on the interference data to obtain a first processing path; using a Bezier curve fitting method to smoothly adjust sharp turning points and discontinuous areas in the first processing path, and eliminating redundant paths in the first processing path to obtain a second processing path; acquiring material property data of the surface to be processed, and calculating and processing the curvature data corresponding to the second processing path in the global curvature field to obtain processing parameters generated by the second processing path, wherein the processing parameters include: tool feed speed and spindle speed.

[0011] Optionally, the motion trajectory of the initial processing paths of the multiple surface sub-areas during the processing is simulated, the interference data between the tool and the workpiece during the simulation process is identified, and the initial processing path is adjusted based on the interference data to obtain a first processing path, including: simulating the motion trajectory of the initial processing paths of the multiple surface sub-areas during the processing, and calculating the relative motion trajectory between the tool and the workpiece corresponding to each path point based on the motion trajectory; determining the tool position and the workpiece surface position of each path point based on the relative motion trajectory between the tool and the workpiece corresponding to each path point; calculating the distance value between the tool position and the workpiece surface position of each path point, and when the distance value is less than the cutting allowance, determining the path point corresponding to the distance value as an interference point; adjusting the initial processing path based on the interference point, and using the adjusted initial processing path to execute "simulating the motion trajectory of the initial processing paths of the multiple surface sub-areas during the processing" until the distance values ​​corresponding to all path points are greater than the cutting allowance to obtain the final adjusted first processing path.

[0012] Optionally, a Bezier curve fitting method is used to smoothly adjust the sharp turning points and discontinuous areas in the first processing path, and redundant paths in the first processing path are eliminated to obtain a second processing path, including: identifying the sharp turning points in the first processing path, and inserting multiple second control points near the sharp turning points, and fitting a Bezier curve based on the multiple second control points, and using the fitted Bezier curve to replace the sharp turning segments corresponding to the sharp turning points in the first processing path to obtain a third processing path; identifying the discontinuous areas in the third processing path, and using an interpolation calculation method to insert multiple third control points near the discontinuous areas, and fitting a Bezier curve based on the third control points, and using the fitted Bezier curve to connect the third processing paths corresponding to the discontinuous areas to obtain a fourth processing path; analyzing the path density of the fourth processing path, identifying redundant areas with a path coverage rate higher than a third preset threshold based on the path density, screening the fourth processing paths in the redundant areas, and eliminating redundant processing paths to obtain the second processing path.

[0013] Optionally, material property data of the surface to be processed is obtained, and combined with the curvature data corresponding to the second processing path in the global curvature field, calculation and processing are performed to obtain processing parameters generated by the second processing path, including: obtaining material property data of the surface to be processed, wherein the material property data include: material hardness, material thermal conductivity and material abrasiveness; using a multivariable optimization algorithm, based on the material hardness data in the material property data, combined with a first empirical coefficient, a preliminary tool feed speed is calculated, based on the material thermal conductivity and material abrasiveness in the material property data, combined with a second empirical coefficient, a preliminary spindle speed is calculated; based on the curvature data corresponding to the second processing path in the global curvature field, the preliminary tool feed speed and the preliminary spindle speed are adjusted to obtain the final tool feed speed and spindle speed.

[0014] The present invention also provides a surface processing path generation system for an ultra-precision diamond lathe, characterized in that it includes: an acquisition unit, used to scan and process the surface to be processed based on a three-dimensional scanning device to obtain three-dimensional point cloud data of the surface to be processed; a division unit, used to perform global curvature calculation based on the three-dimensional point cloud data, and divide the surface to be processed into multiple surface sub-areas based on the calculation results; an optimization unit, used to generate corresponding initial processing paths for the multiple surface sub-areas respectively, and optimize the initial processing paths of the multiple surface sub-areas to obtain a target processing path; an import unit, used to comprehensively verify the target processing path, and when the target processing path passes the comprehensive verification, import the target processing path into the ultra-precision diamond lathe for processing and execution.

[0015] The present invention also provides a computer device, comprising a memory and a processor, wherein the memory stores a computer program, and the processor implements the steps of any one of the above methods when executing the computer program.

[0016] The present invention also provides a computer-readable storage medium on which a computer program is stored. When the computer program is executed by a processor, the steps of any of the above-mentioned methods are implemented.

[0017] The method and system for generating a curved surface machining path for an ultra-precision diamond lathe provided by the present invention realizes high-precision curved surface machining through a series of precise steps. First, the curved surface to be machined is scanned by a three-dimensional scanning device to accurately obtain its three-dimensional point cloud data, thereby ensuring a comprehensive grasp of the machined object. Then, through global curvature calculation, the complex curved surface is divided into multiple sub-areas, so that the initial machining paths are generated respectively according to the curvature characteristics, ensuring that the optimal machining strategy is adopted in different curvature areas.

[0018] After the initial path is generated, the method further reduces interference and errors in processing by optimizing the initial processing path, and obtains a more accurate target processing path. Subsequently, the target processing path is fully verified to ensure the reliability and feasibility of the path and avoid errors in actual processing. Finally, after the verification, the path is imported into the ultra-precision diamond lathe for actual processing, thereby achieving high-precision and high-quality surface processing.

[0019] The technical effect of this method is remarkable, mainly reflected in the ability to accurately process complex surfaces. Through regional curvature calculation and path optimization, it can greatly improve the processing accuracy and surface quality, while reducing tool wear and the probability of error during the processing. The final result is that higher surface finish and shape accuracy can be achieved in ultra-precision processing, meeting the stringent requirements of high-end manufacturing. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 It is a schematic diagram of the steps of a method for generating a curved surface machining path of an ultra-precision diamond lathe in one embodiment of the present invention;

[0021] Figure 2 It is a structural block diagram of a curved surface machining path generation system of an ultra-precision diamond lathe in one embodiment of the present invention;

[0022] Figure 3 It is a schematic block diagram of the structure of a computer device according to an embodiment of the present invention.

[0023] The realization of the purpose, functional features and advantages of the present invention will be further explained in conjunction with embodiments and with reference to the accompanying drawings. DETAILED DESCRIPTION

[0024] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0025] Reference Figure 1 The embodiment of the present invention provides a method for generating a curved surface machining path of an ultra-precision diamond lathe, which is characterized by comprising the following steps:

[0026] S1, scanning the surface to be processed based on a three-dimensional scanning device to obtain three-dimensional point cloud data of the surface to be processed.

[0027] S2, performing global curvature calculation based on the three-dimensional point cloud data, and dividing the surface to be processed into a plurality of surface sub-areas based on the calculation result.

[0028] S3, generating corresponding initial processing paths for the plurality of curved surface sub-regions respectively, and optimizing the initial processing paths for the plurality of curved surface sub-regions to obtain target processing paths.

[0029] S4, comprehensively verifying the target processing path, and if the target processing path passes the comprehensive verification, importing the target processing path into the ultra-precision diamond lathe for processing and execution.

[0030] That is, first of all, it is necessary to use a 3D scanning device to scan and process the surface to be processed, so as to obtain high-precision 3D point cloud data. This step is crucial, because these point cloud data are not only the basis for subsequent curvature calculation and surface division, but also directly determine the accuracy and surface quality of the final processing path. In the specific implementation, the 3D scanning device can use laser scanning, structured light scanning or other methods that can generate high-resolution point cloud data. In order to ensure the integrity and accuracy of the data, the surface to be processed needs to be fully covered during the scanning. Especially when processing complex surfaces, multiple scans and a combination of multiple scanning angles may be required to obtain as complete 3D data as possible.

[0031] After obtaining the three-dimensional point cloud data, the next step is to perform a global curvature calculation. The main purpose of this step is to identify different surface features based on the curvature changes of the surface to be processed, and divide these feature areas into multiple sub-areas. In the implementation process, the point cloud data must first be processed to eliminate noise and smooth the data to ensure the accuracy of subsequent curvature calculations. Then, through a method based on differential geometry, the local curvature can be calculated for each point, and then the high curvature and low curvature areas of the surface can be identified through the global change of curvature. These sub-areas with different curvatures usually have different geometric features and processing difficulties, so they need to be processed separately to optimize the final processing path.

[0032] Once the surface sub-region division is completed, the initial processing path generation stage is entered. For each sub-region, an initial processing path is generated based on its curvature characteristics and geometric shape. Traditional methods usually use regular tool trajectories, such as parallel lines or spirals, but in the present invention, the generation of the initial path needs to be dynamically adjusted in combination with the specific curvature and surface characteristics of the sub-region. For example, in high curvature areas, denser tool paths may be required to ensure surface smoothness, while in low curvature areas, sparser paths can be used to improve processing efficiency. At this time, the physical properties of the tool, such as tool diameter, cutting depth, etc., must also be considered to avoid over-cutting or incomplete processing during the processing process.

[0033] After the initial paths are generated, they need to be optimized to obtain the final target processing path. The key to optimization is to ensure the continuity and smoothness of the entire processing path, so as to avoid the phenomenon of trajectory ripples or uneven roughness in actual processing. When implementing the optimization, Bezier curve fitting, spline interpolation and other methods can be used to smooth the path to ensure smooth connection between paths. In addition, the path needs to be simulated and verified to check for possible tool-workpiece interference problems, and to solve them by adjusting the path or tool parameters.

[0034] After completing the above path optimization, the target processing path obtained must be fully verified to ensure that it can achieve the expected surface quality and processing accuracy in actual processing. During the verification process, the entire processing process can be simulated using CNC simulation software to observe the performance of the path under different working conditions, and by comparing the simulation results with the actual requirements, the path parameters can be further adjusted to ensure that the final processing path can meet the high-precision requirements.

[0035] Finally, when the target machining path has been fully verified, it is imported into the ultra-precision diamond lathe for actual machining execution. Ultra-precision diamond lathes are known for their high rigidity and high precision, and can complete the machining of complex curved surfaces within the micron or even nanometer level of precision. In order to ensure the smooth progress of machining, the operating parameters of the lathe need to be accurately set, and various states of the machining process, such as cutting force, temperature changes, etc., need to be monitored in real time, so as to adjust the machining conditions in time and prevent error accumulation.

[0036] For example, suppose we need to process a complex free-form surface, some areas of which have very high curvature, while other areas are relatively flat. When implementing the above technical solution, after obtaining detailed point cloud data of the surface through 3D scanning, it is found in the global curvature calculation that the high curvature area occupies most of the surface. At this time, in the path generation stage, a more dense and detailed path layout is required in the high curvature area, while a simpler path can be used in the flat area to improve efficiency. Through optimization and simulation verification, the final generated processing path not only ensures the surface quality, but also greatly reduces the processing time. Finally, through actual processing on an ultra-precision lathe, a high-precision surface that meets the design requirements is obtained.

[0037] In one example, after scanning and processing the surface to be processed based on a three-dimensional scanning device to obtain three-dimensional point cloud data of the surface to be processed, the surface processing path generation method also includes: calculating the neighborhood average value of each data point in the three-dimensional point cloud data, identifying target data points whose neighborhood average value is higher than a first preset threshold, and eliminating the target data points in the three-dimensional point cloud data to obtain first three-dimensional point cloud data; dividing the point cloud in the first three-dimensional point cloud data into equally spaced voxel grids, retaining point clouds of a second preset threshold in each grid, and performing group processing on the point clouds retained in each grid to obtain second three-dimensional point cloud data; using a rigid transformation algorithm to transform the second three-dimensional point cloud data into the hyperbolic point cloud data. In the machining coordinate system of a precision diamond lathe, and in the process of the rigid transformation algorithm transforming the second three-dimensional point cloud data, the transformation parameters of the rigid transformation algorithm are adjusted by an iterative nearest point algorithm until the coordinate alignment error of the second three-dimensional point cloud data transformed by the rigid transformation algorithm is lower than a third threshold value, so as to obtain third three-dimensional point cloud data; multiple point clouds are selected as first control points in the third three-dimensional point cloud data, and a NURBS surface model is constructed based on the first control points, and the position of the first control point in the NURBS surface model is adjusted by a least squares method, so that the NURBS surface model approaches the third three-dimensional point cloud data, so as to obtain a target surface model.

[0038] When implementing the surface processing path generation method, the surface to be processed must first be scanned and processed comprehensively based on the three-dimensional scanning equipment to obtain accurate three-dimensional point cloud data. These point cloud data represent the geometric features of the surface to be processed and are the basis for subsequent calculations and processing. In the specific implementation, high-precision equipment such as laser scanning or structured light scanning is usually used to ensure that high-resolution three-dimensional data is obtained. After obtaining these data, in order to further improve the accuracy and efficiency of processing, the neighborhood average is calculated and the target data points are identified. By calculating the neighborhood average of each data point, those data points that are unnecessary for subsequent processing or may introduce errors can be effectively filtered out.

[0039] In the specific implementation, it is first necessary to define a first preset threshold value to determine which data points have a higher neighborhood average value, and remove these target data points from the three-dimensional point cloud data. The result of this processing is to reduce the density of data points, while retaining the part that is more in line with the actual surface shape, forming the first three-dimensional point cloud data. Next, the first three-dimensional point cloud data is divided into equally spaced voxel grids, and the number of point clouds retained in each voxel grid needs to be controlled according to the second preset threshold value. This division and retention operation can effectively reduce the redundancy of data points, making subsequent calculations more efficient, and after grid division, the second three-dimensional point cloud data can be obtained through set processing, further simplifying the complexity of the data.

[0040] After obtaining the simplified second 3D point cloud data, in order to ensure the precise alignment of the machining path with the lathe coordinate system, the point cloud data is converted to the machining coordinate system of the ultra-precision diamond lathe using a rigid transformation algorithm. When implementing this operation, the parameters of the rigid transformation are adjusted by iterative nearest point algorithm to reduce the error in the transformation process. Specifically, the rigid transformation algorithm continuously adjusts the transformation parameters through multiple iterations to ensure that the error between the transformed point cloud data and the target coordinate system is lower than the third threshold. The accuracy of this step directly affects the accuracy of the final machining path, so it is necessary to be very cautious in actual operation to ensure that the third 3D point cloud data is obtained.

[0041] After obtaining the accurately aligned third-dimensional point cloud data, multiple point clouds are selected as the first control points, and a NURBS surface model is constructed based on these control points. The NURBS surface model is known for its flexibility and precision, and can effectively approximate complex surface shapes. After the model is constructed, the positions of these control points are adjusted by the least squares method so that the NURBS surface model can better approximate the third-dimensional point cloud data. The goal of this process is to minimize the error between the model and the actual point cloud data without sacrificing the smoothness of the surface, thereby forming an accurate target surface model.

[0042] For example, suppose that when processing a workpiece with a complex free-form surface, the point cloud data obtained from the initial scan is very dense and contains a large amount of noise and redundant points. By calculating the neighborhood average and eliminating the target data points, the data noise can be effectively reduced, making the surface features more obvious. Subsequently, in the voxel meshing, the data structure is further simplified by controlling the number of point clouds, making the subsequent rigid transformation and NURBS modeling process more efficient. Finally, through the precise adjustment of the rigid transformation and iterative nearest point algorithm, the point cloud data is perfectly aligned with the lathe coordinate system, ensuring the accuracy of the processing path. The construction and adjustment of the NURBS surface model further ensures that the final processing path can accurately meet the complex surface shape of the workpiece, and achieve the expected high precision and high quality requirements in actual processing.

[0043] In one example, a global curvature calculation is performed based on the three-dimensional point cloud data, and the surface to be processed is divided into a plurality of surface sub-areas based on the calculation results, including: calculating the normal vector and tangent vector of the target surface model at each point, and solving the surface parameter equation of the target surface model based on the normal vector and tangent vector to obtain curvature data, wherein the curvature data at least includes: principal curvature, Gaussian curvature and mean curvature; constructing a global curvature field of the target surface model based on the curvature data, wherein the global curvature field is a contour map or a heat map; based on the global curvature field, dividing the target surface model into a plurality of initial surface sub-areas, wherein different initial surface sub-areas correspond to different curvature ranges; determining the intersection area between the plurality of initial surface sub-areas, and introducing a transition area into the plurality of initial surface sub-areas based on the curvature data corresponding to the intersection area in the global curvature field, to obtain a final plurality of surface sub-areas.

[0044] That is, in actual operation, when using 3D point cloud data to calculate the global curvature of the surface to be processed, it is first necessary to extract the normal vector and tangent vector of each point from the point cloud data. Normal vectors and tangent vectors are important tools for describing the geometric morphology of surfaces, which can help us understand and analyze the local characteristics of the surface at each point. Specifically, the normal vector is a vector perpendicular to the surface, and the tangent vector is a vector perpendicular to the normal vector on the surface. After obtaining these vectors, the next step is to solve the surface parameter equation. By analyzing the normal vector and tangent vector, we can further calculate the curvature data.

[0045] In curvature calculation, different curvature forms are usually included, such as principal curvature, Gaussian curvature and mean curvature. The principal curvature reflects the maximum or minimum curvature of the surface in a certain direction, while the Gaussian curvature is the product of the principal curvatures, reflecting the overall curvature of the surface at a certain point. The mean curvature is the average value of the principal curvatures, and is often used to determine whether the surface is convex or concave. Through these curvature data, the geometric characteristics of the surface at different points can be accurately depicted, thus providing an important reference for subsequent surface division and machining path generation.

[0046] Based on the curvature data, the next step is to construct the global curvature field of the target surface model. This global curvature field is usually presented in the form of a contour map or heat map to intuitively display the curvature distribution of the surface in various areas. In the contour map, different contour lines represent different curvature values ​​on the surface, while the heat map reflects the change in curvature through different colors. These graphical representations can help technicians quickly identify areas on the surface where the curvature changes significantly, thereby providing a reference for the subsequent sub-area division.

[0047] In actual operation, the process of dividing the target surface model into multiple initial surface sub-regions is implemented based on the global curvature field. Specifically, different curvature ranges in the curvature field correspond to different surface characteristics, so areas with similar curvature values ​​can be divided into a sub-region. For example, in a complex free-form surface, there may be some areas with relatively gentle curvature, while other areas have drastic changes in curvature. Through such a division, the complex surface can be simplified into multiple sub-regions with similar characteristics, thereby facilitating the subsequent generation and optimization of processing paths.

[0048] However, it is not enough to divide the surface only by the curvature range, because there are often intersection areas with significant curvature changes between multiple initial surface sub-areas. If these intersection areas are not handled properly, they may cause discontinuity or mutations in the processing path between different sub-areas, thus affecting the final processing quality. Therefore, in the process of dividing the surface sub-areas, special attention must be paid to these intersection areas, and transition areas should be introduced based on the curvature data corresponding to these areas.

[0049] The introduction of transition zones is to smooth the curvature changes between different sub-regions, thereby ensuring the continuity and consistency of the machining path. Specifically, in the transition zone, the curvature data gradually changes, smoothly transitioning from the characteristics of one sub-region to the characteristics of another sub-region. This process can be achieved through curvature interpolation or smoothing to ensure that the curvature changes in the transition zone are smooth and continuous.

[0050] For example, when processing a complex curved surface part in the aerospace field, the areas with drastic curvature changes can be processed separately from relatively gentle areas by constructing a global curvature field and dividing the sub-areas. At the junction of these sub-areas, the introduction of transition zones can ensure the seamless connection of the processing path between different areas, thereby effectively avoiding surface quality problems caused by sudden changes in curvature. Ultimately, through this series of processing steps, multiple smooth and continuous surface sub-areas can be obtained, providing an accurate path planning basis for ultra-precision machining.

[0051] In one example, corresponding initial processing paths are generated for the multiple surface sub-regions, including: based on the curvature ranges of the multiple surface sub-regions, the multiple surface sub-regions are divided into a first type of surface sub-regions and a second type of surface sub-regions, wherein the curvature range corresponding to the first type of surface sub-regions is higher than the curvature range corresponding to the second type of surface sub-regions; using a contour following method to perform path generation processing on the second type of surface sub-regions to obtain initial processing paths corresponding to the second type of surface sub-regions; using a parallel cutting method to perform path generation processing on the first type of surface sub-regions to obtain initial processing paths corresponding to the first type of surface sub-regions.

[0052] That is, in the process of generating complex surface machining paths, different path generation methods need to be used according to the characteristics of different surface sub-regions. Specifically, based on the curvature ranges of multiple surface sub-regions, these sub-regions can be divided into two categories, namely, first-class surface sub-regions and second-class surface sub-regions. Among them, the curvature range of the first-class surface sub-regions is higher, which means that the surfaces in these regions change more dramatically and usually have more complex geometric shapes, while the curvature range of the second-class surface sub-regions is relatively low, indicating that the surfaces in these regions are relatively flat and the geometric characteristics are relatively simple.

[0053] For the second type of surface sub-area, since its curvature range is relatively low, which means that the surface changes relatively slowly, the contour following method can be used for path generation processing. The contour following method is a path generation method based on the surface contour line. Its basic idea is to generate a processing path by following the contour lines or feature lines of the surface. This method has high efficiency and stability when processing areas with small curvature changes, because in these areas, the movement of the tool can move relatively smoothly along the surface contour, thereby effectively avoiding processing errors caused by sudden changes in curvature. For example, on a flat optical lens surface, the contour following method can generate a uniform and continuous processing path, thereby ensuring the smoothness and consistency of the lens surface.

[0054] However, for the first type of surface sub-region, due to its high curvature range and complex surface changes, the contour following method may not be able to effectively cope with it. This is because in areas with drastic changes in curvature, the path generated along the contour lines or feature lines may cause instability in tool movement, thereby affecting the machining accuracy. Therefore, when processing these areas, it is more appropriate to use the parallel cutting method for path generation. The parallel cutting method is a method for generating parallel cutting paths based on the tool. Its core idea is to generate a regular and stable machining path by making the tool cut in parallel directions on the surface. This method can effectively reduce the instability of tool movement when processing areas with large changes in curvature, thereby improving machining accuracy.

[0055] For example, in the surface machining of a complex aerospace component, suppose that the curvature of some areas of the component changes dramatically, such as some sharp corners or complex concave and convex structures. In these areas, the parallel cutting method can fix the cutting direction of the tool in a parallel direction to ensure that the tool moves stably on the surface, thereby generating an accurate machining path. In addition, the parallel cutting method can further optimize the smoothness and accuracy of the path by adjusting the cutting step, so as to better adapt to the complex geometry of the surface.

[0056] Therefore, by using the contour following method and the parallel cutting method respectively to perform path generation processing on the surface sub-regions with different curvature ranges, the initial processing path can be generated according to their respective geometric characteristics. This sub-region path generation strategy can not only ensure the smoothness and continuity of the processing path, but also effectively improve the processing accuracy and efficiency. In practical applications, the contour following method and the parallel cutting method each play their unique advantages, so that the final generated processing path can accurately adapt to the complex morphology of the surface, providing a reliable path basis for ultra-precision processing. The effective implementation of this method ensures a high degree of consistency in processing quality, thereby meeting the processing requirements of high-precision complex surfaces.

[0057] In one example, the initial processing paths of the multiple surface sub-areas are optimized to obtain a target processing path, including: simulating the motion trajectory of the initial processing paths of the multiple surface sub-areas during the processing, identifying the interference data between the tool and the workpiece during the simulation process, and adjusting the initial processing path based on the interference data to obtain a first processing path; using a Bezier curve fitting method to smoothly adjust the sharp turning points and discontinuous areas in the first processing path, and eliminating redundant paths in the first processing path to obtain a second processing path; acquiring material property data of the surface to be processed, and calculating and processing the curvature data corresponding to the second processing path in the global curvature field to obtain processing parameters generated by the second processing path, wherein the processing parameters include: tool feed speed and spindle speed.

[0058] That is, in the process of optimizing the initial processing paths of multiple surface sub-areas to generate the target processing paths, it is first necessary to simulate the motion trajectory of the initial processing paths in actual processing. The core of this simulation process is to analyze the motion behavior of the tool when executing these paths, so as to identify the interference data that may occur between the tool and the workpiece. The occurrence of interference phenomena usually means that at certain positions, the movement of the tool will produce unexpected contact with the workpiece, which may cause processing errors and even lead to a decrease in the surface quality of the workpiece. By identifying these interference data, necessary adjustments can be made to the initial processing path to eliminate or reduce this interference phenomenon, thereby obtaining a more reasonable first processing path.

[0059] For example, when processing an aerospace part with a complex surface, assuming that there are highly concentrated curvature changes in certain areas of the part, it may cause the tool to come into contact with the workpiece in certain sections of the path. In this case, by analyzing the interference data of these areas, the tool direction or tool feed speed of the initial processing path can be appropriately adjusted to avoid interference. For example, the path can be slightly offset or the tool entry angle can be adjusted so that the tool can pass through these complex areas smoothly without causing destructive effects on the workpiece surface.

[0060] After obtaining the first processing path, further optimization steps involve smoothing the sharp turning points and discontinuous areas in the path, which is usually achieved through the Bezier curve fitting method. The Bezier curve fitting method has good smoothness and can effectively reduce the mutations in the path, so that the tool can move along a more continuous and gentle path during actual processing. This smoothing process is crucial to maintaining the quality of the workpiece surface because it can reduce vibration and tool wear caused by path turning, thereby ensuring the stability and accuracy of the processing. For example, in the ultra-precision processing of an optical lens, if there are obvious turning points in the initial processing path, these turning points may leave uneven processing marks on the lens surface. Through Bezier curve fitting, these turning points can be smoothed into continuous curves, thereby generating a more uniform surface in actual processing.

[0061] In addition, path optimization also involves eliminating redundant paths. In the actual initial path, some repeated or unnecessary path segments may be generated due to the limitations of the generation algorithm or other factors. These redundant paths not only increase the processing time, but may also affect the final processing quality. Therefore, by identifying and eliminating these redundant paths through the optimization algorithm, the processing process can be simplified, production costs can be reduced, and processing efficiency can be improved. The final optimization result is the second processing path. This path has been adjusted for interference, smoothed, and redundant paths have been eliminated, and can better meet the processing needs of complex surfaces.

[0062] After obtaining the second processing path, it is necessary to further calculate the processing parameters in combination with the material property data of the surface to be processed. Material property data such as hardness, elastic modulus, etc. will directly affect the selection of tool feed speed and spindle speed, because different materials have different requirements for cutting force, temperature, etc. during the processing process. For example, for a high-hardness metal material, if the tool feed speed is too fast or the spindle speed is too high, it may cause increased tool wear or thermal deformation on the workpiece surface. Therefore, it is necessary to combine the curvature data of the surface and the material properties, and determine reasonable processing parameters through precise calculations to ensure smooth processing.

[0063] For example, in the surface processing of a high-hardness alloy material, based on the high curvature area of ​​the surface, it may be necessary to reduce the feed speed of the tool to avoid surface cracks, and adjust the spindle speed appropriately to control the cutting temperature. This parameter adjustment based on material properties and curvature data can ensure that the machining path always maintains the best cutting state during execution, thereby obtaining a final product with higher surface finish and better precision.

[0064] Through the above series of optimization processes, from adjusting interference data to Bezier curve fitting, to eliminating redundant paths, and finally calculating machining parameters in combination with material properties, a highly optimized target machining path can be generated. This path can not only minimize machining errors during execution, but also ensure a balance between machining efficiency and surface quality, providing a systematic and efficient solution for ultra-precision machining of complex surfaces.

[0065] In one example, the motion trajectory of the initial machining paths of the multiple surface sub-areas during the machining process is simulated, the interference data between the tool and the workpiece during the simulation process is identified, and the initial machining path is adjusted based on the interference data to obtain a first machining path, including: simulating the motion trajectory of the initial machining paths of the multiple surface sub-areas during the machining process, and calculating the relative motion trajectory between the tool and the workpiece corresponding to each path point based on the motion trajectory; determining the tool position and the workpiece surface position of each path point based on the relative motion trajectory between the tool and the workpiece corresponding to each path point; calculating the distance value between the tool position and the workpiece surface position of each path point, and determining the path point corresponding to the distance value as an interference point when the distance value is less than the cutting allowance; adjusting the initial machining path based on the interference point, and using the adjusted initial machining path to execute "simulating the motion trajectory of the initial machining paths of the multiple surface sub-areas during the machining process" until the distance values ​​corresponding to all path points are greater than the cutting allowance, to obtain the final adjusted first machining path.

[0066] That is, during the machining process, simulating the initial machining paths of multiple surface sub-areas and identifying the interference data between the tool and the workpiece are key steps to ensure machining accuracy and surface quality. First, by simulating the motion trajectory of the initial machining path, the relative motion between the tool and the workpiece can be predicted before machining. This process includes calculating the tool position and workpiece surface position corresponding to each path point, thereby determining the relative motion trajectory of the tool relative to the workpiece. In this process, the distance value between the tool and the workpiece surface at each path point is crucial. If the calculation results show that the distance between the tool and the workpiece surface at certain path points is less than the predetermined cutting allowance, these path points are marked as interference points.

[0067] The appearance of interference points means that in the actual machining process, the tool may make unnecessary contact or cut with the workpiece, resulting in reduced machining accuracy or damage to the workpiece surface. Therefore, these interference points must be processed. The processing method includes adjusting the initial machining path so that the tool will not interfere when passing through these points. This adjustment may involve changing the position of the path point, optimizing the tool feed angle, or adjusting the cutting depth.

[0068] After the adjustment is completed, the adjusted path is used again to simulate the machining process to verify whether the distance between the tool and the workpiece surface at all path points is greater than the cutting allowance. If there are still interference points, the path needs to be further adjusted until all path points meet the requirements. This iterative process ensures that the first machining path generated in the end is interference-free and can be processed stably.

[0069] For example, suppose that when machining a complex surface, the simulation of path motion finds that the distance between the path point in a certain area and the workpiece surface is too small, which may cause the tool to overcut. At this time, the engineer can adjust the path so that the tool is slightly lifted or the feed angle is changed when approaching the area to avoid overcutting. After the adjusted path is verified, the final machining path can ensure that the tool moves in the optimal trajectory throughout the machining process, thereby achieving the expected machining effect.

[0070] Through such path adjustment, not only can possible interference be eliminated, but the machining process can also be optimized and the final surface quality of the workpiece can be improved. This method is especially important for ultra-precision machining, because in this type of machining, even a small path deviation may have a significant impact on the final machining result. Therefore, the method of simulating and adjusting the initial machining path is an effective means to ensure the quality of complex surface machining.

[0071] In one example, a Bezier curve fitting method is used to smoothly adjust the sharp turning points and discontinuous areas in the first processing path, and to eliminate redundant paths in the first processing path to obtain a second processing path, including: identifying the sharp turning points in the first processing path, inserting multiple second control points near the sharp turning points, fitting a Bezier curve based on the multiple second control points, and using the fitted Bezier curve to replace the sharp turning segments corresponding to the sharp turning points in the first processing path to obtain a third processing path; identifying the discontinuous areas in the third processing path, inserting multiple third control points near the discontinuous areas by an interpolation calculation method, and fitting a Bezier curve based on the third control points, and using the fitted Bezier curve to connect the third processing paths corresponding to the discontinuous areas to obtain a fourth processing path; analyzing the path density of the fourth processing path, identifying redundant areas with a path coverage higher than a third preset threshold based on the path density, screening the fourth processing paths in the redundant areas, and eliminating redundant processing paths to obtain the second processing path.

[0072] That is, in an actual operation example, the Bezier curve fitting method is widely used to optimize the sharp turning points and discontinuous areas of complex surface machining paths to ensure the smoothness and continuity of the path. First, in the first machining path, sharp turning points are key positions that may cause vibration and surface defects during tool movement. In order to smooth these areas, the system identifies all sharp turning points and inserts multiple second control points near these positions. Through these control points, a Bezier curve can be accurately fitted, which can smoothly transition sharp turns, thereby avoiding machining problems caused by sudden changes in direction. This processing method not only improves the smoothness of the path, but also reduces the mechanical stress caused by drastic changes in direction during the machining process, thereby extending the service life of the tool and improving the surface quality of the machining.

[0073] Next, for the discontinuous areas in the processing path, the continuity of the path is increased through interpolation calculation. The system will first identify the discontinuous parts of the path and insert multiple third control points near the two ends of these areas. Then, a Bezier curve is fitted using these control points, which can smoothly connect the discontinuous path segments to form a coherent third processing path. This process ensures the overall continuity of the path and avoids processing defects or surface unevenness caused by path discontinuity.

[0074] In addition, in order to further optimize the path, the system analyzes the path density of the fourth processing path, especially focusing on the coverage of the path. In some areas, redundancy may occur due to the overly dense paths. This redundancy not only wastes processing time, but also may affect the surface quality. Therefore, by analyzing the path density, the system can identify those areas where the coverage is higher than the preset threshold, and screen and eliminate the paths in these areas. By eliminating redundant paths, the system finally generates a second processing path, which is not only optimized in terms of sharp turning points and smoothness, but also avoids processing redundancy, thereby improving overall processing efficiency.

[0075] For example, suppose that when processing a complex optical lens, the initial path contains multiple sharp turning points, which may cause instantaneous acceleration or deceleration of the tool during actual processing, thereby causing unnecessary vibration. By inserting control points near these turning points and fitting Bezier curves, the sharp turns can be smoothed, allowing the tool to move at a stable speed, ensuring the accuracy of the processing and the smoothness of the surface. Similarly, when processing discontinuous areas in the path, by inserting control points and fitting Bezier curves, the discontinuity of the path can be eliminated, making the entire processing process smoother and more consistent. Finally, by eliminating redundant paths, the system optimizes the entire processing path, making the processing process more efficient and without redundant steps, thereby significantly improving the processing quality and efficiency.

[0076] In one example, material property data of the surface to be processed is obtained, and curvature data corresponding to the second processing path in the global curvature field are combined for calculation and processing to obtain processing parameters generated by the second processing path, including: obtaining material property data of the surface to be processed, wherein the material property data include: material hardness, material thermal conductivity and material abrasiveness; using a multivariable optimization algorithm, based on the material hardness data in the material property data, combined with a first empirical coefficient, a preliminary tool feed speed is calculated, based on the material thermal conductivity and material abrasiveness in the material property data, combined with a second empirical coefficient, a preliminary spindle speed is calculated; based on the curvature data corresponding to the second processing path in the global curvature field, the preliminary tool feed speed and the preliminary spindle speed are adjusted to obtain final tool feed speed and spindle speed.

[0077] That is, in order to ensure the machining accuracy and efficiency of the surface to be machined, it is first necessary to obtain the material property data of the surface to be machined, which is the key to optimizing the machining parameters. Material property data include the hardness, thermal conductivity and abrasiveness of the material, which directly affect the tool wear, temperature control and quality of the machined surface during the machining process. After obtaining these material property data, the preliminary machining parameters are calculated through a multivariable optimization algorithm.

[0078] In the specific operation, firstly, the hardness data of the material is combined with the first empirical coefficient to calculate the preliminary tool feed speed. The higher the hardness of the material, the more difficult the processing is. Therefore, the tool feed speed needs to be reduced accordingly to prevent excessive wear or breakage of the tool. At the same time, the selection of the empirical coefficient is crucial because it can correct the algorithm based on previous processing experience, making the calculated tool feed speed more practical.

[0079] Then, a preliminary spindle speed is calculated by incorporating a second empirical coefficient, taking into account the thermal conductivity and abrasiveness of the material. Materials with better thermal conductivity can dissipate heat more effectively, which allows for higher spindle speeds during machining, while materials with high abrasiveness require lower spindle speeds to reduce tool wear. Similarly, the use of the second empirical coefficient can modify the spindle speed based on actual machining conditions to make it more in line with specific machining requirements.

[0080] However, it is not enough to rely solely on material property data to set processing parameters. Further adjustments need to be made in combination with the curvature data of the second processing path in the global curvature field. The global curvature field can reflect the changes in curvature of the surface to be processed in different areas, and these changes will directly affect the force conditions and surface processing quality of the tool during the processing. Based on the curvature data, the preliminary calculated tool feed speed and spindle speed may need to be slightly adjusted. For example, in areas with larger curvatures, the tool may need to be slowed down to prevent vibration or burrs in surface processing; in areas with smaller curvatures, the processing speed can be appropriately increased to improve processing efficiency.

[0081] Finally, by adjusting the preliminary tool feed speed and spindle speed, the final tool feed speed and spindle speed suitable for the second machining path are obtained. These final machining parameters not only take into account the basic characteristics of the material, but also make full use of the information of the curvature field to ensure that both efficient machining speed and excellent surface quality can be maintained during the machining process.

[0082] For example, when processing a high-hardness titanium alloy material, its hardness and abrasiveness are both high, so the initial calculated tool feed rate is low, and the spindle speed is also set within a moderate range. However, due to the good thermal conductivity of the material, the spindle speed can be slightly increased to speed up the processing speed. However, when entering an area with a large change in curvature, the system automatically reduces the tool feed rate to avoid uneven textures or vibrations on the machined surface. Ultimately, through these meticulous adjustments, the generated machining path can improve the overall machining efficiency while ensuring machining accuracy, achieving efficient and high-quality surface machining.

[0083] like Figure 2 As shown, the embodiment of the present application also provides a surface machining path generation system for an ultra-precision diamond lathe, which is characterized by comprising:

[0084] An acquisition unit 1 is used to scan the surface to be processed based on a three-dimensional scanning device to obtain three-dimensional point cloud data of the surface to be processed;

[0085] A division unit 2, configured to perform global curvature calculation based on the three-dimensional point cloud data, and divide the surface to be processed into a plurality of surface sub-areas based on the calculation result;

[0086] The optimization unit 3 is used to generate corresponding initial processing paths for the plurality of curved surface sub-regions respectively, and optimize the initial processing paths for the plurality of curved surface sub-regions to obtain target processing paths;

[0087] The import unit 4 is used to fully verify the target processing path, and when the target processing path passes the comprehensive verification, import the target processing path into the ultra-precision diamond lathe for processing and execution.

[0088] In this embodiment, for the specific implementation of each unit in the above system embodiment, please refer to the above method embodiment, which will not be repeated here.

[0089] Reference Figure 3 In an embodiment of the present invention, a computer device is also provided. The computer device may be a server, and its internal structure may be as follows: Figure 3 As shown. The computer device includes a processor, a memory, a display screen, an input device, a network interface and a database connected through a system bus. Among them, the processor designed by the computer is used to provide computing and control capabilities. The memory of the computer device includes a non-volatile storage medium and an internal memory. The non-volatile storage medium stores an operating system, a computer program and a database. The internal memory provides an environment for the operation of the operating system and the computer program in the non-volatile storage medium. The database of the computer device is used to store the corresponding data in this embodiment. The network interface of the computer device is used to communicate with an external terminal through a network connection. When the computer program is executed by the processor, the above method is implemented.

[0090] Those skilled in the art will understand that Figure 3 The structure shown in the figure is merely a block diagram of a portion of the structure related to the solution of the present invention, and does not constitute a limitation on the computer device to which the solution of the present invention is applied.

[0091] An embodiment of the present invention further provides a computer-readable storage medium on which a computer program is stored, and when the computer program is executed by a processor, the above method is implemented. It can be understood that the computer-readable storage medium in this embodiment can be a volatile readable storage medium or a non-volatile readable storage medium.

[0092] Those skilled in the art can understand that all or part of the processes in the above-mentioned embodiment methods can be completed by instructing the relevant hardware through a computer program, and the computer program can be stored in a non-volatile computer-readable storage medium. When the computer program is executed, it can include the processes of the embodiments of the above-mentioned methods. Among them, any reference to memory, storage, database or other media provided by the present invention and used in the embodiments may include non-volatile and / or volatile memory. Non-volatile memory may include read-only memory (ROM), programmable ROM (PROM), electrically programmable ROM (EPROM), electrically erasable programmable ROM (EEPROM) or flash memory. Volatile memory may include random access memory (RAM) or external cache memory. As an illustration and not limitation, RAM is available in a variety of forms, such as static RAM (SRAM), dynamic RAM (DRAM), synchronous DRAM (SDRAM), double-speed data rate SDRAM (SSRSDRAM), enhanced SDRAM (ESDRAM), synchronous link (Synchlink) DRAM (SLDRAM), memory bus (Rambus) direct RAM (RDRAM), direct memory bus dynamic RAM (DRDRAM), and memory bus dynamic RAM.

[0093] It should be noted that, in this article, the terms "include", "comprises" or any other variations thereof are intended to cover non-exclusive inclusion, so that a process, device, article or method including a series of elements includes not only those elements, but also includes other elements not explicitly listed, or also includes elements inherent to such process, device, article or method. In the absence of further restrictions, an element defined by the sentence "includes a ..." does not exclude the presence of other identical elements in the process, device, article or method including the element.

[0094] The above description is only a preferred embodiment of the present invention, and does not limit the patent scope of the present invention. Any equivalent structure or equivalent process transformation made by using the contents of the present invention specification and drawings, or directly or indirectly applied in other related technical fields, are also included in the patent protection scope of the present invention.

Claims

1. A method for generating a curved surface machining path for an ultra-precision diamond lathe, characterized in that: The following steps are involved: Scanning the surface to be processed based on a three-dimensional scanning device to obtain three-dimensional point cloud data of the surface to be processed; After scanning the surface to be processed based on the three-dimensional scanning device to obtain the three-dimensional point cloud data of the surface to be processed, the surface processing path generation method also includes: calculating the neighborhood average value of each data point in the three-dimensional point cloud data, identifying the target data points whose neighborhood average value is higher than the first preset threshold, and eliminating the target data points in the three-dimensional point cloud data to obtain the first three-dimensional point cloud data; dividing the point cloud in the first three-dimensional point cloud data into equally spaced voxel grids, retaining the point cloud of the second preset threshold in each grid, and performing collective processing on the point cloud retained in each grid to obtain the second three-dimensional point cloud data; using a rigid transformation algorithm to transform the second three-dimensional point cloud data into the ultra-precision metal In the machining coordinate system of a diamond lathe, during the process of the rigid transformation algorithm transforming the second three-dimensional point cloud data, the transformation parameters of the rigid transformation algorithm are adjusted by an iterative nearest point algorithm until the coordinate alignment error of the second three-dimensional point cloud data transformed by the rigid transformation algorithm is lower than a third threshold value, thereby obtaining third three-dimensional point cloud data; selecting a plurality of point clouds as first control points in the third three-dimensional point cloud data, constructing a NURBS surface model based on the first control points, and adjusting the position of the first control point in the NURBS surface model by using a least squares method, so that the NURBS surface model approaches the third three-dimensional point cloud data, thereby obtaining a target surface model; Performing global curvature calculation based on the three-dimensional point cloud data, and dividing the surface to be processed into a plurality of surface sub-areas based on the calculation result; performing global curvature calculation based on the three-dimensional point cloud data, and dividing the surface to be processed into a plurality of surface sub-areas based on the calculation result, including: calculating the normal vector and tangent vector of the target surface model at each point, and solving the surface parameter equation of the target surface model based on the normal vector and the tangent vector to obtain curvature data, wherein the curvature data at least includes: principal curvature, Gaussian curvature and mean curvature. Average curvature; constructing a global curvature field of the target surface model based on the curvature data, wherein the global curvature field is a contour map or a heat map; dividing the target surface model into a plurality of initial surface sub-regions based on the global curvature field, wherein different initial surface sub-regions correspond to different curvature ranges; determining the intersection regions between the plurality of initial surface sub-regions, and introducing transition regions into the plurality of initial surface sub-regions based on the curvature data corresponding to the intersection regions in the global curvature field, so as to obtain a plurality of final surface sub-regions; Generating corresponding initial processing paths for the multiple surface sub-regions respectively, and optimizing the initial processing paths for the multiple surface sub-regions to obtain target processing paths; generating corresponding initial processing paths for the multiple surface sub-regions respectively, including: dividing the multiple surface sub-regions into a first type of surface sub-regions and a second type of surface sub-regions based on the curvature ranges of the multiple surface sub-regions, wherein the curvature range corresponding to the first type of surface sub-regions is higher than the curvature range corresponding to the second type of surface sub-regions; using a contour following method, performing path generation processing on the second type of surface sub-regions to obtain the initial processing paths corresponding to the second type of surface sub-regions; using a parallel cutting method, performing path generation processing on the first type of surface sub-regions to obtain the initial processing paths corresponding to the first type of surface sub-regions; The initial machining paths of the plurality of surface sub-regions are optimized to obtain a target machining path, including: simulating the motion trajectory of the initial machining paths of the plurality of surface sub-regions during the machining process, identifying the interference data between the tool and the workpiece during the simulation process, and adjusting the initial machining path based on the interference data to obtain a first machining path; using a Bezier curve fitting method to smoothly adjust the sharp turning points and discontinuous regions in the first machining path, and eliminating redundant paths in the first machining path to obtain a second machining path; acquiring material property data of the surface to be machined, and calculating and processing the curvature data corresponding to the second machining path in the global curvature field to obtain machining parameters for generating the second machining path, wherein the machining parameters include: tool feed speed and spindle speed; The target machining path is fully verified, and when the target machining path passes the full verification, the target machining path is introduced into the ultra-precision diamond lathe for machining execution.

2. The method for generating a curved surface machining path according to claim 1, characterized in that: Simulating the motion trajectory of the initial machining paths of the plurality of surface sub-regions during the machining process, identifying interference data between the tool and the workpiece during the simulation process, and adjusting the initial machining path based on the interference data to obtain a first machining path, including: Simulating the motion trajectory of the initial machining paths of the plurality of curved surface sub-regions during the machining process, and calculating the relative motion trajectory between the tool and the workpiece corresponding to each path point based on the motion trajectory; Determine the tool position and workpiece surface position of each path point based on the relative motion trajectory between the tool and the workpiece corresponding to each path point; Calculating the distance value between the tool position and the workpiece surface position at each path point, and determining the path point corresponding to the distance value as an interference point when the distance value is less than the cutting allowance; The initial machining path is adjusted based on the interference point, and the adjusted initial machining path is used to execute "simulating the motion trajectory of the initial machining paths of the multiple surface sub-areas during the machining process" until the distance values ​​corresponding to all path points are greater than the cutting allowance, thereby obtaining the final adjusted first machining path.

3. The method for generating a curved surface machining path according to claim 1, characterized in that: The Bezier curve fitting method is used to smoothly adjust the sharp turning points and discontinuous areas in the first processing path, and the redundant paths in the first processing path are eliminated to obtain the second processing path, including: Identify a sharp turning point in the first processing path, insert a plurality of second control points near the sharp turning point, fit a Bezier curve based on the plurality of second control points, and use the fitted Bezier curve to replace the sharp turning segment corresponding to the sharp turning point in the first processing path, so as to obtain a third processing path; Identify the discontinuous area in the third processing path, and insert a plurality of third control points near the discontinuous area by using an interpolation calculation method, and fit a Bezier curve based on the third control points, and use the fitted Bezier curve to connect the third processing paths corresponding to the discontinuous area to obtain a fourth processing path; Analyze the path density of the fourth processing path, identify redundant areas with path coverage higher than a third preset threshold based on the path density, screen the fourth processing paths in the redundant areas, and eliminate redundant processing paths to obtain the second processing path.

4. The method for generating a curved surface machining path according to claim 1, characterized in that: Acquiring material property data of the surface to be processed, and performing calculation processing in combination with curvature data corresponding to the second processing path in the global curvature field to obtain processing parameters for generating the second processing path, including: Acquiring material property data of the surface to be processed, wherein the material property data includes: material hardness, material thermal conductivity and material abrasiveness; Using a multivariable optimization algorithm, based on the material hardness data in the material property data, combined with a first empirical coefficient, a preliminary tool feed speed is calculated, and based on the material thermal conductivity and material abrasiveness in the material property data, combined with a second empirical coefficient, a preliminary spindle speed is calculated; The preliminary tool feed speed and the preliminary spindle speed are adjusted based on the curvature data corresponding to the second machining path in the global curvature field to obtain the final tool feed speed and spindle speed.

5. A surface machining path generation system for an ultra-precision diamond lathe, characterized in that: include: An acquisition unit is used to scan the surface to be processed based on a three-dimensional scanning device to obtain three-dimensional point cloud data of the surface to be processed; After scanning the surface to be processed based on the three-dimensional scanning device to obtain the three-dimensional point cloud data of the surface to be processed, the surface processing path generation method also includes: calculating the neighborhood average value of each data point in the three-dimensional point cloud data, identifying the target data points whose neighborhood average value is higher than the first preset threshold, and eliminating the target data points in the three-dimensional point cloud data to obtain the first three-dimensional point cloud data; dividing the point cloud in the first three-dimensional point cloud data into equally spaced voxel grids, retaining the point cloud of the second preset threshold in each grid, and performing collective processing on the point cloud retained in each grid to obtain the second three-dimensional point cloud data; using a rigid transformation algorithm to transform the second three-dimensional point cloud data into the ultra-precision metal In the machining coordinate system of a diamond lathe, during the process of the rigid transformation algorithm transforming the second three-dimensional point cloud data, the transformation parameters of the rigid transformation algorithm are adjusted by an iterative nearest point algorithm until the coordinate alignment error of the second three-dimensional point cloud data transformed by the rigid transformation algorithm is lower than a third threshold value, thereby obtaining third three-dimensional point cloud data; selecting a plurality of point clouds as first control points in the third three-dimensional point cloud data, constructing a NURBS surface model based on the first control points, and adjusting the position of the first control point in the NURBS surface model by using a least squares method, so that the NURBS surface model approaches the third three-dimensional point cloud data, thereby obtaining a target surface model; A division unit is used to perform global curvature calculation based on the three-dimensional point cloud data, and divide the surface to be processed into a plurality of surface sub-areas based on the calculation result; perform global curvature calculation based on the three-dimensional point cloud data, and divide the surface to be processed into a plurality of surface sub-areas based on the calculation result, including: calculating the normal vector and tangent vector of the target surface model at each point, and solving the surface parameter equation of the target surface model based on the normal vector and the tangent vector to obtain curvature data, wherein the curvature data at least includes: principal curvature, Gaussian curvature, rate and average curvature; constructing a global curvature field of the target surface model based on the curvature data, wherein the global curvature field is a contour map or a heat map; dividing the target surface model into a plurality of initial surface sub-regions based on the global curvature field, wherein different initial surface sub-regions correspond to different curvature ranges; determining the intersection regions between the plurality of initial surface sub-regions, and introducing transition regions into the plurality of initial surface sub-regions based on the curvature data corresponding to the intersection regions in the global curvature field, so as to obtain a plurality of final surface sub-regions; An optimization unit is used to generate corresponding initial processing paths for the multiple surface sub-regions respectively, and optimize the initial processing paths of the multiple surface sub-regions to obtain target processing paths; generating corresponding initial processing paths for the multiple surface sub-regions respectively, including: dividing the multiple surface sub-regions into a first type of surface sub-regions and a second type of surface sub-regions based on the curvature ranges of the multiple surface sub-regions, wherein the curvature range corresponding to the first type of surface sub-regions is higher than the curvature range corresponding to the second type of surface sub-regions; using a contour following method, performing path generation processing on the second type of surface sub-regions to obtain the initial processing paths corresponding to the second type of surface sub-regions respectively; using a parallel cutting method, performing path generation processing on the first type of surface sub-regions to obtain the initial processing paths corresponding to the first type of surface sub-regions respectively; The initial machining paths of the plurality of surface sub-regions are optimized to obtain a target machining path, including: simulating the motion trajectory of the initial machining paths of the plurality of surface sub-regions during the machining process, identifying the interference data between the tool and the workpiece during the simulation process, and adjusting the initial machining path based on the interference data to obtain a first machining path; using a Bezier curve fitting method to smoothly adjust the sharp turning points and discontinuous regions in the first machining path, and eliminating redundant paths in the first machining path to obtain a second machining path; acquiring material property data of the surface to be machined, and calculating and processing the curvature data corresponding to the second machining path in the global curvature field to obtain machining parameters for generating the second machining path, wherein the machining parameters include: tool feed speed and spindle speed; The import unit is used to fully verify the target processing path, and when the target processing path passes the comprehensive verification, import the target processing path into the ultra-precision diamond lathe for processing and execution.

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