Optical processing method based on magneto-rheological dynamic feeding direction

Abstract

The application relates to the technical field of optical processing, and specifically provides an optical processing method based on a magnetorheological dynamic feeding direction, which comprises the following steps: firstly, obtaining a surface shape error of a workpiece; then, selecting a suitable magnetorheological polishing wheel, determining a removal function thereof, establishing a reference removal function distribution when a deflection angle of the magnetorheological polishing wheel is 0, setting a machining track of the magnetorheological polishing wheel, differentially designing the deflection angle of the magnetorheological polishing wheel at each dwell point, transforming the deflection angle to obtain a deflected removal function distribution according to the reference removal function distribution, and calculating a dwell time of the magnetorheological polishing wheel at each dwell point according to the deflected removal function distribution; and finally, machining the workpiece according to the machining track, the dwell time distribution and the deflection angle. The feeding direction of the polishing wheel changes with the machining position, and periodic machining marks generated by the magnetorheological asymmetric removal function during traditional fixed direction machining are inhibited.

Description

Technical Field

[0001] This invention belongs to the field of optical processing technology, and particularly relates to an optical processing method based on magnetorheological dynamic feed direction. Background Technology

[0002] Magnetorheological polishing technology has become one of the key processes in the manufacture of high-precision optical components, especially aspherical and freeform surface components, due to its advantages such as stable polishing area, good deterministic removal function, and small subsurface damage. Its basic principle is to use a flexible "polishing pad" formed by the rheological changes of magnetorheological fluid in a gradient magnetic field to remove minute amounts of material from the workpiece surface.

[0003] Traditional magnetorheological polishing processes typically employ a fixed polishing wheel feed direction. This means that the spatial orientation of the removal function in the workpiece coordinate system remains unchanged throughout the machining path. However, the shape of the magnetorheological removal function is usually non-rotationally symmetric (bullet-shaped), with distinct major and minor axis directions. Its material removal rate decays more slowly along the major axis and more rapidly along the minor axis. When the removal function moves along a predetermined trajectory in a fixed direction, non-uniform material accumulation is easily generated, resulting in periodic, trajectory-related "tool marks" or "mid-frequency errors" on the machined surface.

[0004] Existing technologies primarily employ multi-round processing, with each round featuring different processing trajectories and polishing wheel feed directions. This results in tool marks of varying directions and periods in each round, which then overlap and disrupt the cyclical tool marks. Each round requires independent path planning and process parameter settings. To "cover" the marks from the previous round, subsequent rounds often necessitate additional material removal, leading to a total material removal exceeding the theoretical value required for simply correcting surface shape errors. This makes the method complex and inefficient. Summary of the Invention

[0005] In view of this, the present invention aims to provide an optical processing method based on magnetorheological dynamic feed direction. It adopts a dynamic removal function deflection strategy to make the feed direction of the polishing wheel change with the processing position to generate a specific deflection angle, thereby changing the spatial orientation of the removal function in the workpiece coordinate system. This breaks the anisotropic material superposition mode caused by the fixed direction removal function, fundamentally reducing the generation of periodic processing marks. A reasonable dynamic deflection strategy can suppress the generation of tool marks with a single wheel processing.

[0006] To achieve the above objectives, the technical solution created by this invention is implemented as follows: This invention provides an optical processing method based on magnetorheological dynamic feed direction, comprising: Obtain the surface shape error of the workpiece in the workpiece coordinate system; Determine the removal function of the magnetorheological polishing wheel and establish the baseline removal function distribution of the magnetorheological polishing wheel when the deflection angle is 0 in the workpiece coordinate system; Set the machining trajectory of the magnetorheological polishing wheel, and set the deflection angle of the magnetorheological polishing wheel at each dwell point on the machining trajectory, so that there are at least two dwell points where the deflection angle of the magnetorheological polishing wheel is different; The reference removal function distribution is rotated and transformed based on the deflection angle of the magnetorheological polishing wheel at each dwell point to obtain the deflected removal function distribution; The dwell time of the magnetorheological polishing wheel at each dwell point was calculated based on the surface shape error and the distribution of the removal function after deflection. The workpiece is subjected to magnetorheological polishing according to the processing parameters of each dwell point on the processing trajectory. The processing parameters include the deflection angle and dwell time of the magnetorheological polishing wheel.

[0007] Preferably, the removal function of the magnetorheological polishing wheel is measured as follows: A magnetorheological polishing wheel was used to polish a test piece made of the same material as the workpiece at a single point. The removal function of the magnetorheological polishing wheel was obtained by measuring the removal amount distribution per unit time of the single-point polishing.

[0008] Preferably, the baseline removal function distribution in the workpiece coordinate system is established when the magnetorheological polishing wheel deflection angle is 0, including: Establish the coordinate system of the removal function: with the polishing point of the magnetorheological polishing wheel as the center O and the major axis of the shape of the removal function as the Y-axis; Establish a workpiece coordinate system that is stationary relative to the workpiece; When the X-axis and Y-axis directions of the removal function coordinate system are the same as those of the workpiece coordinate system, and the XOY plane is parallel, the removal function of the magnetorheological polishing wheel in the removal function coordinate system is the reference removal function distribution of the magnetorheological polishing wheel when the deflection angle of the magnetorheological polishing wheel in the workpiece coordinate system is 0.

[0009] Preferably, the processing parameters also include: the normal direction of each dwell point.

[0010] Preferably, the difference in deflection angle of the magnetorheological polishing wheel is set to a fixed value for adjacent dwell points.

[0011] Preferably, the processing trajectory is a grating trajectory.

[0012] Preferably, the calculation process for the distribution of the removal function after deflection is as follows: Preferably, the dwell time of the magnetorheological polishing wheel at each dwell point is calculated using an iterative convolution method.

[0013] Preferably, the process of calculating the residence time of the magnetorheological polishing wheel at each residence point includes: The convolution removal model is established as follows: ; in, express The amount of space removed. This represents the removal function. Indicates the length of stay; The discrete data matrix model is established based on the convolution removal model as follows: ; in, Indicates the workpiece The surface shape error distribution of discrete data points, where any element This represents the surface shape error of any discrete data point on the workpiece. Indicates the processing trajectory The residence time distribution of each residence point, where any element This represents the dwell time at any dwell point on the processing trajectory. Indicates the magnetorheological polishing wheel in At each outpost The removal rate of discrete data points, where any element Indicates the magnetorheological polishing wheel in the first... During processing at the first outpost, the first Material removal rate for each discrete data point; The processing trajectory is calculated based on the discrete data matrix model. The distribution of stay time at each station.

[0014] Compared with the prior art, the present invention can achieve the following beneficial effects: This invention employs a dynamic removal function deflection strategy, dynamically changing the feed direction of the polishing wheel at each processing position. This causes the spatial orientation of the removal function in the workpiece coordinate system to change with the position, breaking the anisotropic material superposition mode caused by the traditional fixed-direction removal function. This fundamentally destroys the formation conditions of periodic processing marks and effectively suppresses processing tool marks.

[0015] Traditional processing methods require multiple passes, each with independently planned paths and set process parameters to cover the marks left by the previous pass. This often results in the total removal amount exceeding the theoretical correction value. In contrast, this invention requires only a single pass to simultaneously correct surface shape errors and suppress tool marks, eliminating the need for additional path planning and parameter adjustments. This improves mirror removal accuracy and significantly shortens the processing cycle. Furthermore, the invention's design concept of dynamically changing the direction of the removal function is applicable not only to magnetorheological polishing but also to other processing methods with asymmetric removal functions, such as ion beam polishing and small-head polishing. Attached Figure Description

[0016] The accompanying drawings, which form part of this invention, are used to provide a further understanding of the invention. The illustrative embodiments and descriptions of the invention are used to explain the invention and do not constitute an undue limitation of the invention. In the drawings: Figure 1 This is a flowchart of an optical processing method based on magnetorheological dynamic feed direction provided according to an embodiment of the present invention; Figure 2 This is a schematic diagram of the initial surface shape of a workpiece before processing, provided by an embodiment of the present invention; Figure 3 This is a schematic diagram of the removal function of a magnetorheological polishing wheel provided according to an embodiment of the present invention; Figure 4 This is a schematic diagram of the surface shape obtained after machining in a traditional fixed feed direction. Figure 5 This is a schematic diagram of local tool marks on a workpiece after traditional fixed feed direction machining. Figure 6 This is a schematic diagram of the surface shape obtained after dynamic feed direction machining according to the method provided in the embodiment of the present invention. Detailed Implementation

[0017] 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 specific embodiments. It should be understood that the specific embodiments described herein are only for explaining the invention and do not constitute a limitation thereof. Similar elements in different embodiments are referred to by associated similar element reference numerals. In the following embodiments, many details are described to facilitate a better understanding of the invention. However, those skilled in the art will readily recognize that some features may be omitted in different situations, or may be replaced by other elements, materials, or methods. In some cases, some operations related to the invention are not shown or described in the specification. This is to avoid obscuring the core parts of the invention with excessive description. For those skilled in the art, detailed description of these related operations is not necessary; the relevant operations can be fully understood based on the description in the specification and general technical knowledge in the art.

[0018] It should be noted that, unless otherwise specified, the embodiments and features described in this invention can be combined to form various implementations. Furthermore, the order of the steps or actions in the method description can be changed or adjusted in a manner readily apparent to those skilled in the art. Therefore, the various orders in the specification and drawings are merely for the clear description of a particular embodiment and do not imply a mandatory order, unless otherwise stated that a particular order must be followed.

[0019] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," and "counterclockwise," etc., indicating orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation on this invention. Furthermore, the terms "first," "second," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, features defined with "first," "second," etc., may explicitly or implicitly include one or more of that feature. In the description of this invention, unless otherwise stated, "a plurality of" means two or more.

[0020] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art will understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0021] The invention will now be described in detail with reference to the accompanying drawings and embodiments.

[0022] Please see Figure 1 In one embodiment of the present invention, an optical processing method based on magnetorheological dynamic feed direction is provided, comprising: S1: Obtain the surface shape error of the workpiece in the workpiece coordinate system; S2: Determine the removal function of the magnetorheological polishing wheel and establish the baseline removal function distribution of the magnetorheological polishing wheel when the deflection angle is 0 in the workpiece coordinate system; S3: Set the processing trajectory of the magnetorheological polishing wheel, and set the deflection angle of the polishing wheel at each dwell point on the processing trajectory, so that there are at least two dwell points where the deflection angle of the magnetorheological polishing wheel is different. The reference removal function distribution is rotated and transformed based on the deflection angle of the magnetorheological polishing wheel at each dwell point to obtain the deflected removal function distribution; S4: Calculate the dwell time of the magnetorheological polishing wheel at each dwell point based on the surface shape error and the distribution of the removal function after deflection; S5: Perform magnetorheological polishing on the workpiece according to the processing parameters of each dwell point on the processing trajectory. The processing parameters include the deflection angle and dwell time of the magnetorheological polishing wheel.

[0023] In step S1, it is first necessary to obtain the surface shape error of the workpiece in the workpiece coordinate system. Here, the workpiece is an optical lens. The workpiece coordinate system refers to a coordinate system that is stationary relative to the workpiece. Usually, a point on the workpiece is taken as the origin, and the workpiece's machining surface is taken as the XOY plane to establish the coordinate system. The Z direction is the perpendicular direction of the workpiece's machining surface, which is used to reflect the material protrusions or depressions on the workpiece's machining surface.

[0024] In the process of measuring surface shape error, it is necessary to measure the initial surface shape and dimensions of the workpiece before processing using measuring equipment such as an interferometer. Then, the target surface shape of the workpiece is set according to the processing requirements, that is, the surface shape to be achieved after processing. The surface shape data measured by the interferometer is a series of discretized data points. The surface shape of the workpiece is reflected by the vector height at the discrete data points. After obtaining the initial surface shape and the target surface shape, the difference between the two yields the discretized surface shape error in the workpiece coordinate system. The surface shape error is expressed as... , ,in, Indicates the first The position coordinates of discrete data points in the XOY plane of the workpiece coordinate system. Indicates the index of discrete data points. Indicates the first The difference in elevation between the initial surface shape and the target surface shape for each discrete data point represents the target amount of material to be removed. Indicates the first The vector height of the initial surface shape for each discrete data point. Indicates the first The vector height of the target surface shape for each discrete data point. This represents the total number of discrete data points.

[0025] In step S2, a suitable magnetorheological polishing wheel is first selected based on the workpiece size, initial surface shape, and target surface shape. The processing parameters of the magnetorheological polishing wheel are then determined, including magnetic field strength, rotational speed, reduction, and rheological fluid composition ratio. Under these parameters, the magnetorheological polishing wheel is used to perform single-point polishing on a test piece made of the same material as the workpiece, forming removal pits. The morphology of the removal pits is detected using a coordinate measuring machine or interferometer to obtain the removal amount per unit time for single-point polishing. This yields the discretized removal function of the magnetorheological polishing wheel, which is expressed as... ,in, , Indicates the position in the coordinate system after removing the function. Material removal rate at the site Indicates the discrete point number on the magnetorheological polishing wheel. This represents the total number of discrete points on the magnetorheological polishing wheel. It should be noted that since the distribution of the removal function of the magnetorheological polishing wheel is non-uniform and asymmetric, discrete points are taken within the distribution range of the removal function of the magnetorheological polishing wheel. The material removal rate corresponding to the discrete points reflects the removal function of the workpiece. The coordinates of these discrete points in the removal function coordinate system (or magnetorheological polishing wheel coordinate system) reflect the material removal capacity of each point on the magnetorheological polishing wheel. The removal function coordinate system is centered at the polishing point (polishing center) of the magnetorheological polishing wheel, with the major axis of the removal function shape as the Y-axis and the minor axis of the removal function shape as the X-axis.

[0026] After determining the removal function of the magnetorheological polishing wheel, in order to describe the change in the feed direction of the magnetorheological polishing wheel, it is necessary to obtain the spatial orientation of the removal function in the workpiece coordinate system. Therefore, this embodiment of the invention first needs to determine a reference removal function distribution with a deflection angle of 0 in the workpiece coordinate system.

[0027] When the X-axis and Y-axis directions of the removal function coordinate system and the workpiece coordinate system are the same, and their XOY planes are parallel, the removal function of the magnetorheological polishing wheel in the removal function coordinate system is considered as the reference removal function when the magnetorheological polishing wheel's deflection angle in the workpiece coordinate system is 0. Therefore, during the machining process, there is only a translational relationship between the removal function coordinate system B and the workpiece coordinate system A, which can be described as: ; in, , The translation homogeneous transformation matrix is... This represents the position coordinates of a point on the magnetorheological polishing wheel in the workpiece coordinate system A. This relationship determines the initial mapping method of the removal function from the removal function coordinate system to the workpiece coordinate system, and clarifies the expression of the zero deflection angle of the magnetorheological polishing wheel in the workpiece coordinate system, so as to facilitate subsequent description of different deflection angles based on this.

[0028] In step S3, based on the workpiece's shape and size, and the removal function of the magnetorheological polishing wheel, the machining trajectory of the magnetorheological polishing wheel is planned and designed. Commonly used machining trajectories include, but are not limited to, grating trajectories, helical trajectories, and circular trajectories. The machining trajectory consists of a series of discrete dwell points and can be represented as follows: , ,in Indicates the processing trajectory Upper The three-dimensional spatial coordinates of each dwelling point in the workpiece coordinate system This represents the total number of dwell points. When determining the location of each dwell point, in order to control the attitude of the magnetorheological polishing wheel during surface machining, it is also necessary to calculate the normal direction of the lens surface at each dwell point. The direction of the normal to the lens surface at each dwell point is represented as follows: , The normal direction of the dwell point is used to guide the spindle direction of the magnetorheological polishing wheel, so that the polishing wheel always maintains the correct relative posture with the workpiece surface during the processing, thereby ensuring the stability of the removal function shape.

[0029] To effectively suppress periodic machining marks, this embodiment of the invention employs a dynamic removal function deflection strategy, whereby at each dwell point on the machining trajectory, the magnetorheological polishing wheel is rotated around its main axis by different deflection angles. This changes the orientation of the major axis of the removal function shape in the workpiece coordinate system, i.e., the feed direction of the magnetorheological polishing wheel. The dynamic removal function deflection strategy can be designed according to actual machining requirements, setting the deflection angle of the magnetorheological polishing wheel at each dwell point on the machining trajectory. This ensures that there are at least two different deflection angles of the magnetorheological polishing wheel at the points where the machining trajectory stops.

[0030] As a typical and easy-to-implement deflection strategy, the difference in deflection angle between the polishing wheels at adjacent dwell points is set to a fixed value. That is, the deflection angle changes according to an arithmetic progression: ; in, This indicates the deflection angle at the first dwelling point. Indicates the first The deflection angle of each dwell point. This strategy ensures that the removal function direction rotates along the machining trajectory, causing the anisotropic material removal to superimpose and cancel each other out, thereby fundamentally destroying the conditions for the formation of periodic tool marks.

[0031] In step S4, based on the dynamic removal function deflection strategy, the deflection angle of the magnetorheological polishing wheel at each dwell point on the machining trajectory is determined. Then, based on the machining trajectory and the deflection angle, the reference removal function distribution is rotated and transformed to update the removal function distribution of the magnetorheological polishing wheel after deflection at each dwell point. , , Indicates the first on the machined surface of the workpiece Material removal rate at discrete data points. It should be noted that both discrete data points and dwell points refer to points on the workpiece machining surface. However, the difference between discrete data points and dwell points is that discrete data points are points reflecting the workpiece surface shape in step S1, while dwell points are points designed on the machining trajectory. The two do not correspond and coincide. When the magnetorheological polishing wheel processes at a certain dwell point, it will change the vector height of some discrete data points on the workpiece.

[0032] For the distribution of the removal function after deflection To solve this problem, we first need to rotate the distribution of the reference removal function according to the deflection angle of the magnetorheological polishing wheel at the current residence point to obtain a new removal function. : ; in, satisfy: ; in, This represents the first position on the magnetorheological polishing wheel in the removal function coordinate system B. Coordinates of discrete points The first on the magnetorheological polishing wheel Discrete points deflected in coordinate system B, removing the function New coordinates after the angle This represents the material removal function before rotational transformation. This represents the material removal function after rotational transformation, where the removal efficiency of the polishing tool before rotation is... .

[0033] , Let be the rotation transformation matrix.

[0034] Furthermore, based on the relationship between the removal function coordinate system B and the workpiece coordinate system A in step S2, the coordinates on the workpiece surface are expressed by the following formula: The discrete data points are transformed into coordinates in the function coordinate system. : ; in, For the first The coordinates of the nth station are then... At each dwelling point, the magnetorheological polishing wheel deflects... During angle machining, the coordinates on the workpiece surface in the workpiece coordinate system are... Material removal rate at discrete data points for: ; in, The following transformation yields: .

[0035] The distribution of the removal function after deflection can be obtained through the above coordinate transformation process. , .

[0036] After obtaining the removal function distribution after deflection, the dwell time of the magnetorheological polishing wheel at each dwell point can be calculated based on the surface error and the removal function distribution after deflection. The dwell time can be calculated using a two-point convolution iteration method, based on the convolution removal model of the following formula: ; in, express The amount of space removed. This represents the removal function. Indicates the length of stay.

[0037] The above convolution removal model can be transformed into a discrete data matrix model, and expressed as: ; in, Indicates the workpiece The surface shape error distribution of discrete data points, where any element can be represented by... express, , Indicates the first on the workpiece The surface shape error of a discrete data point Indicates the processing trajectory The residence time distribution of each residence point, where any element can be used as... express, , Indicates the first on the processing trajectory The length of stay at each stop, Indicates the magnetorheological polishing wheel in At each outpost The removal rate of discrete data points, where Indicates the magnetorheological polishing wheel in the first... During processing at the first outpost, the first Material removal rate for discrete data points.

[0038] Solving the convolution removal model yields the processing trajectory. Distribution of stay time at each checkpoint The exact solution of the convolution removal model generally does not meet the non-negativity requirement of processing time in practical engineering. Therefore, it is necessary to transform the problem into an optimization problem, setting an optimization objective: ; The optimal non-negative residence time of the magnetorheological polishing wheel can be obtained by solving the optimization objective. ,in, Describes the objective function for optimization. Represents the regularization factor. Right now , Z Right now .

[0039] When the obtained solution meets the optimization objective, this solution This will serve as the final length of stay for each stop.

[0040] In step S5, after the above design and calculation, all machining parameters for each dwelling point on the machining trajectory are obtained. All machining parameters are integrated to generate machining code. The machining code includes the coordinates of each dwelling point on the machining trajectory, the normal direction at each dwelling point, the deflection angle of the magnetorheological polishing wheel at each dwelling point, and the dwell time. A robot or machine tool is used to drive the magnetorheological polishing wheel to execute the machining code. During machining, the magnetorheological polishing wheel moves sequentially to each dwelling point according to the machining code, orients itself according to the set deflection angle, and holds for the corresponding time to complete deterministic polishing of the entire diameter.

[0041] To verify the method of this embodiment of the invention, the method was used to simulate the fabrication of an optical lens with a diameter of 200mm, such as... Figure 2 As shown, the root mean square value of the initial surface shape of the lens is 6.20 × 10⁻⁶. -4 mm. After selecting the magnetorheological tool, the removal function is obtained as follows: Figure 3 As shown. Set the grating processing trajectory with a step size of 1 mm and a trajectory spacing of 2 mm.

[0042] In contrast, when this tool is first used for conventional magnetorheological processing, the removal function does not deflect during the processing. For example... Figure 4 and Figure 5 As shown, the root mean square value after processing is 4.87 × 10⁻⁶. -6 mm, and obvious periodic tool marks appear on the surface after processing.

[0043] like Figure 6 As shown, the tool is then used to process the material according to the method of this embodiment of the invention. During the processing, a typical deflection strategy is adopted, that is, the difference in deflection angle of the magnetorheological polishing wheel at adjacent dwell points is a fixed value. The root mean square value after processing is 9.71 × 10⁻⁶. -6 Compared to machining with a fixed feed direction, the machined profile still maintains a high convergence rate of 98.5%, and no periodic tool marks appear. This machining method can significantly suppress the generation of tool marks.

[0044] In summary, the above description is merely a preferred embodiment of this specification and is not intended to limit the scope of protection of this specification. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this specification should be included within the scope of protection of this specification.

[0045] The systems, apparatuses, modules, or units described in one or more of the above embodiments may be implemented by a computer chip or entity, or by a product having a certain function. A typical implementation device is a computer. Specifically, a computer may be, for example, a personal computer, a laptop computer, a cellular phone, a camera phone, a smartphone, a personal digital assistant, a media player, a navigation device, an email device, a game console, a tablet computer, a wearable device, or any combination of these devices.

[0046] It should also be noted that the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0047] The various embodiments in this specification are described in a progressive manner. Similar or identical parts between embodiments can be referred to interchangeably. Each embodiment focuses on describing the differences from other embodiments. In particular, the system embodiments are basically similar to the method embodiments, so the description is relatively simple; relevant parts can be referred to the descriptions in the method embodiments.

Claims

1. An optical processing method based on magnetorheological dynamic feed direction, characterized in that, include: Obtain the surface shape error of the workpiece in the workpiece coordinate system; Determine the removal function of the magnetorheological polishing wheel and establish the baseline removal function distribution of the magnetorheological polishing wheel when the deflection angle is 0 in the workpiece coordinate system; The processing trajectory of the magnetorheological polishing wheel is set, and the deflection angle of the magnetorheological polishing wheel at each dwell point on the processing trajectory is set, such that there are at least two dwell points where the deflection angle of the magnetorheological polishing wheel is different. The reference removal function distribution is rotated and transformed based on the deflection angle of the magnetorheological polishing wheel at each dwell point to obtain the deflected removal function distribution; The dwell time of the magnetorheological polishing wheel at each dwell point is calculated based on the surface shape error and the distribution of the removal function after deflection. The workpiece is subjected to magnetorheological polishing according to the processing parameters of each dwell point on the processing trajectory. The processing parameters include the deflection angle and dwell time of the magnetorheological polishing wheel.

2. The optical processing method based on magnetorheological dynamic feed direction according to claim 1, characterized in that, The removal function of the magnetorheological polishing wheel is measured as follows: The magnetorheological polishing wheel is used to perform single-point polishing on an experimental piece of the same material as the workpiece. The removal function of the magnetorheological polishing wheel is obtained by measuring the removal amount distribution per unit time of single-point polishing.

3. The optical processing method based on magnetorheological dynamic feed direction according to claim 1, characterized in that, The establishment of the reference removal function distribution in the workpiece coordinate system when the magnetorheological polishing wheel deflection angle is 0 includes: Establish a coordinate system for the removal function: with the polishing point of the magnetorheological polishing wheel as the center O and the major axis of the shape of the removal function as the Y-axis; Establish a workpiece coordinate system that is stationary relative to the workpiece; When the removal function coordinate system and the workpiece coordinate system have the same X-axis direction and the same Y-axis direction, and the XOY plane is parallel, the removal function of the magnetorheological polishing wheel in the removal function coordinate system is the reference removal function distribution of the magnetorheological polishing wheel when the deflection angle of the magnetorheological polishing wheel in the workpiece coordinate system is 0.

4. The optical processing method based on magnetorheological dynamic feed direction according to claim 1, characterized in that, The processing parameters also include the normal direction of each dwell point.

5. The optical processing method based on magnetorheological dynamic feed direction according to claim 1, characterized in that, For adjacent dwell points, the difference in deflection angle of the magnetorheological polishing wheel is set to a fixed value.

6. The optical processing method based on magnetorheological dynamic feed direction according to claim 1, characterized in that, The processing trajectory is a grating trajectory.

7. The optical processing method based on magnetorheological dynamic feed direction according to claim 1, characterized in that, The dwell time of the magnetorheological polishing wheel at each dwell point was calculated using an iterative convolution method.

8. The optical processing method based on magnetorheological dynamic feed direction according to claim 7, characterized in that, The process of calculating the residence time of the magnetorheological polishing wheel at each residence point includes: The convolution removal model is established as follows: ； in, express The amount of space removed. This represents the removal function. Indicates the length of stay; The discrete data matrix model is established based on the convolution removal model as follows: ； in, Indicating the workpiece The surface shape error distribution of discrete data points, where any element This represents the surface shape error of any discrete data point on the workpiece. Indicates the processing trajectory The residence time distribution of each residence point, where any element This represents the dwell time at any dwell point on the processing trajectory. This indicates that the magnetorheological polishing wheel is in At each outpost The removal rate of discrete data points, where any element This indicates that the magnetorheological polishing wheel is in the first... During processing at the first outpost, the first Material removal rate for each discrete data point; The processing trajectory is calculated based on the discrete data matrix model. The distribution of stay time at each station.

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