Magnetorheological removal function change measurement device and method with shunt design

Abstract

The present invention relates to the field of optical processing technology, and in particular to a magnetorheological removal function change measurement device and method with a branch design, the device comprising a processing magnetorheological polishing system, a testing magnetorheological polishing system, a supply system and a control system; in the processing magnetorheological polishing system, a robot and a processing magnetorheological polishing device process optical elements, and the processing magnetorheological polishing device measures in real time the flow of magnetorheological fluid inside the optical element during the processing; in the testing magnetorheological polishing system, the testing magnetorheological polishing device processes the optical element and measures in real time the flow of magnetorheological fluid inside the optical element during the processing; the supply system simultaneously supplies magnetorheological fluid to the processing magnetorheological polishing device and the testing magnetorheological polishing device; in the method, if magnetorheological fluid is blocked in the processing magnetorheological polishing system, the pipeline in the testing magnetorheological polishing system can be used to replace it, so as to achieve consistency of processing parameters and rapid restart of the processing state after being suspended due to pipeline blockage.

Description

Technical Field

[0001] The present invention belongs to the technical field of optical processing, and in particular relates to a device and method for measuring changes in a magnetorheological removal function with a branch design. Background Art

[0002] Magnetorheological finishing (MRF) is an advanced optical manufacturing technology that has been developed in recent years. It offers numerous advantages, including stable removal performance, controllable edge effects, minimal subsurface damage, no photocopying, strong shape-modifying capabilities, and high machining accuracy. Consequently, MRF has garnered widespread attention in high-precision optical processing.

[0003] The prerequisite for magnetorheological polishing technology to achieve high-precision processing is to rely on the stability of the removal function, that is, the removal function is stable during the processing or the change of the removal function during the processing is knowable. The stability of the removal function is inseparable from the performance of the magnetorheological fluid. During the long-term processing, the performance of the magnetorheological fluid will gradually change. For example, the moisture in the magnetorheological fluid will evaporate and remain on the mirror surface, causing its proportion to change. Therefore, it is inevitable that the removal function will change during the long-term processing. This requires measuring some parameters during the processing to reflect the changes in the removal function, such as measuring the viscosity of the liquid through a pressure sensor, measuring the flow rate of the liquid through a flow meter, etc., but these parameters are all indirect reflections of the changes in the removal function. There are also some parameters related to the changes in the removal function that cannot or are inconvenient to measure during the processing, such as iron powder concentration, polishing powder concentration, and the particle size of polishing powder and iron powder. It is difficult to truly and comprehensively understand the changes in the removal function by relying solely on existing measurement parameters.

[0004] However, it is impossible or inconvenient to measure the actual removal function change on the optical element during the processing process. The reason is that the processing range of the processing equipment is limited, and the spatial size of the optical element to be processed occupies most of the processing interval, especially for the processing of large-aperture or even ultra-large-aperture optical elements. Therefore, there is not enough space within the limited processing range to place another optical element to measure the removal function change; when there is enough interval in the processing area to place the test optical element and measure the removal function during the processing, this requires the processing equipment to be separated from the current processing state and process the test optical element with a new processing parameter, and then return to the processing state, but since the current processing state is broken, the continuity of the processing is interrupted. Even if the control program is used to control the processing equipment to return to the processing state at the time of interruption, due to the limitations of the motion performance of the processing equipment, it is impossible to be the same as the processing state before the interruption, which eventually leads to special processing marks on the surface of the optical element after processing, and this processing mark is difficult to remove in the subsequent processing process, which ultimately affects the processing accuracy. Summary of the Invention

[0005] In view of this, the present invention aims to provide a magnetorheological removal function change measurement device and method with a branch design. The device can measure more processing parameters to reflect the removal function changes and obtain the actual removal function changes during the processing without breaking the actual processing state and interrupting the processing continuity. If the magnetorheological fluid in the processing magnetorheological polishing system is blocked, the pipeline in the test magnetorheological polishing system can be used as a substitute to achieve consistency of processing parameters and rapid restart of the processing state after being suspended due to pipeline blockage.

[0006] To achieve the above object, the technical solution created by the present invention is implemented as follows:

[0007] A magnetorheological removal function change measurement device with a branch design includes a processing magnetorheological polishing system, a testing magnetorheological polishing system, a supply system, and a control system. The processing magnetorheological polishing system includes a robot and a processing magnetorheological polishing device arranged at the free end of the robot. The control system controls the robot and the processing magnetorheological polishing device to process an optical element. The processing magnetorheological polishing device measures the flow of magnetorheological fluid inside the processing magnetorheological polishing device in real time during the processing and transmits the measurement results to the control system. The testing magnetorheological polishing system includes a position adjustment platform and a testing magnetorheological polishing device. The optical element is placed on the position adjustment platform. The control system controls the position adjustment platform to adjust the processing position of the optical element. The control system controls the testing magnetorheological polishing device to cooperate with the position adjustment platform to process the optical element, and measures the flow of magnetorheological fluid inside the testing magnetorheological polishing device in real time during the processing and transmits the measurement results to the control system. The supply system is controlled by the control system and simultaneously provides magnetorheological fluid to the processing magnetorheological polishing device and the testing magnetorheological polishing device.

[0008] Furthermore, the magnetorheological polishing equipment for processing and / or testing includes: a magnetorheological polishing component for processing optical elements; a magnetorheological fluid flow measurement component for real-time measurement of the flow of the magnetorheological fluid during processing; and a stop valve controlled by a control system to control the flow and delivery of the magnetorheological fluid.

[0009] Furthermore, the magnetorheological polishing assembly includes: a polishing wheel, which contacts the optical element and cooperates with the magnetorheological fluid to process the optical element; a polishing motor, which is controlled by the control system and drives the polishing motor; a nozzle, which is connected to the supply system and provides magnetorheological fluid to the polishing wheel; and a magnet module, which changes the stiffness of the magnetorheological fluid at the polishing wheel.

[0010] Furthermore, the magnetorheological fluid flow measurement component includes: a pressure sensor, which measures the pressure generated during the flow of the magnetorheological fluid and transmits the measured pressure to the control system; an electromagnetic flowmeter, which measures the flow of the magnetorheological fluid and transmits the measured flow to the control system.

[0011] Furthermore, the magnetorheological polishing system for processing and / or the magnetorheological polishing system for testing also includes: a force sensor for measuring the change in force between the magnetorheological fluid and the optical element in real time, and transmitting the measured force to the control system; a line laser measuring instrument for measuring the change in thickness of the magnetorheological fluid ribbon in real time, and transmitting the measured ribbon thickness to the control system.

[0012] Furthermore, the magnetorheological polishing system for testing also includes a particle size measurement and medium content detection device; the particle size measurement and medium content detection device measures the particle size of iron powder and polishing powder in the magnetorheological fluid, as well as the content of iron powder, polishing powder and moisture in real time, and transmits the measured information to the control system.

[0013] Furthermore, the supply system includes: a liquid storage module, which stores and stirs the magnetorheological fluid; a recovery module, which is controlled by the control system, recovers the magnetorheological fluid under the control of the control system, and transports the recovered magnetorheological fluid to the liquid storage module; and a supply module, which is controlled by the control system, transports the magnetorheological fluid in the liquid storage module to the processing magnetorheological polishing equipment and / or the testing magnetorheological polishing equipment.

[0014] A method for measuring changes in a magnetorheological removal function of a shunt design, and a device for measuring changes in a magnetorheological removal function of a shunt design provided by the present invention, comprising:

[0015] S1: Control the supply system to deliver magnetorheological fluid to the processing magnetorheological polishing system and the testing magnetorheological polishing system, and control the processing magnetorheological polishing system and the testing magnetorheological polishing system to process the optical element to be processed and the testing optical element respectively;

[0016] S2: Real-time monitoring of changes in the magnetorheological fluid in the magnetorheological polishing system to determine whether a blockage of the magnetorheological fluid occurs in the magnetorheological polishing system; if blockage occurs, executing step S3; otherwise, repeating step S2 until the processing of the optical element to be processed is completed;

[0017] S3: Exchange the corresponding blocked pipelines in the processing magnetorheological polishing system and the test magnetorheological polishing system; restart the processing magnetorheological polishing system to process the optical element to be processed; install the cleaned pipelines into the test magnetorheological polishing system; restart the test magnetorheological polishing system to process the test optical element; return to step S2.

[0018] Furthermore, in step S2, the allowable pressure range of the magnetorheological fluid in the magnetorheological polishing system is determined; in the magnetorheological polishing system, if the current pressure of the magnetorheological fluid does not exceed the allowable pressure range, it is determined that magnetorheological fluid blockage has not occurred, and step S2 is repeated; if the current pressure of the magnetorheological fluid exceeds the allowable pressure range, it is determined that magnetorheological fluid blockage has occurred, and step S3 is executed.

[0019] Furthermore, step S2 further includes:

[0020] During the current data collection time, monitoring the processing information of the test optical element by the test magnetorheological polishing system and the composition information of the magnetorheological fluid in the test magnetorheological polishing system;

[0021] Determining removal function information of the optical element to be processed according to current processing information;

[0022] The next data collection time for the removal function information and the magnetorheological fluid composition information is determined according to the current removal function information and the magnetorheological fluid composition information.

[0023] Compared with the prior art, the present invention can achieve the following beneficial effects:

[0024] (1) The present invention creates a device and method for measuring changes in the magnetorheological removal function with a branch design. Under the premise of not breaking the actual processing state and interrupting the processing continuity, more processing parameters can be measured to reflect the changes in the removal function and the changes in the actual removal function during the processing can be obtained. In addition, if the magnetorheological fluid in the processing magnetorheological polishing system is blocked, the pipeline in the test magnetorheological polishing system can be used as a substitute to achieve consistency in processing parameters and rapid restart of the processing state after being suspended due to pipeline blockage.

[0025] (2) In the magnetorheological removal function change measurement method with a branch design created by the present invention, by continuously measuring and testing the magnetorheological fluid parameters and removal function change information in the magnetorheological polishing system, data support is provided for judging the shape error distribution of the optical element to be processed after processing, and data support is provided for the subsequent virtual processing removal function change of the optical element to be processed, as well as guidance for the selection of processing parameters and processing strategies for further long-term processing. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] The accompanying drawings, which constitute part of the present invention, are intended to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are intended to explain the present invention and do not constitute an undue limitation of the present invention. In the accompanying drawings:

[0027] Figure 1 A schematic structural diagram of a magnetorheological removal function change measurement device with a branch design according to an embodiment of the present invention at one viewing angle;

[0028] Figure 2 A schematic structural diagram of the magnetorheological removal function change measurement device with a branch design according to an embodiment of the present invention from another perspective;

[0029] Figure 3 A flow chart of a method for measuring changes in magnetorheological removal function using a branch design as described in an embodiment of the present invention.

[0030] Description of reference numerals:

[0031] 1. Control system; 2. Robot; 3. Optical element; 4. Position adjustment table; 5. Laboratory table; 6. Independent support frame; 7. Polishing wheel; 8. Polishing motor; 9. Nozzle; 10. Magnet module; 11. Magnetorheological support frame; 12. Recovery box; 13. Pressure sensor; 14. Electromagnetic flowmeter; 15. Liquid storage module; 16. Recovery module; 17. Supply module; 18. Force sensor; 19. Line laser measuring instrument. DETAILED DESCRIPTION

[0032] In order to make the purpose, technical solutions and advantages of the present invention more clearly understood, the present invention is 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 used to explain the present invention and do not constitute a limitation of the present invention.

[0033] It should be noted that, in the absence of conflict, the embodiments of the present invention and the features in the embodiments can be combined with each other.

[0034] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention. In addition, the terms "first", "second" and the like are only used for descriptive purposes and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Thus, features defined as "first", "second" and the like may explicitly or implicitly include one or more of the features. In the description of the present invention, unless otherwise specified, "multiple" means two or more.

[0035] In the description of the present invention, it should be noted that, unless otherwise expressly specified or limited, the terms "installed," "connected," and "connected" should be understood in a broad sense. For example, they can refer to fixed connections, detachable connections, or integral connections; they can refer to mechanical connections or electrical connections; they can refer to direct connections or indirect connections through an intermediate medium; and they can refer to internal connections between two components. Those skilled in the art can understand the specific meanings of the above terms in the present invention based on specific circumstances.

[0036] The present invention will be described in detail below with reference to the accompanying drawings and in combination with embodiments.

[0037] like Figures 1 to 2 As shown, the magnetorheological removal function change measurement device with a branch design described in an embodiment of the present invention includes a processing magnetorheological polishing system, a testing magnetorheological polishing system, a supply system, and a control system 1. The processing magnetorheological polishing system includes a robot 2 and a processing magnetorheological polishing device disposed at the free end of robot 2. The control system 1 controls the robot 2 and the processing magnetorheological polishing device to process an optical element 3. The processing magnetorheological polishing device measures the flow of magnetorheological fluid within the processing magnetorheological polishing device in real time during processing and transmits the measurement results to the control system 1. The testing magnetorheological polishing system includes the testing magnetorheological polishing device and a position adjustment platform 4. The optical element 3 is placed on the position adjustment platform 4. The control system 1 controls the position adjustment platform 4 to adjust the processing position of the optical element 3. The control system 1 controls the testing magnetorheological polishing device in conjunction with the position adjustment platform 4 to process the optical element 3. The control system 1 measures the flow of magnetorheological fluid within the testing magnetorheological polishing device in real time during processing and transmits the measurement results to the control system 1. The supply system is controlled by the control system 1 and supplies magnetorheological fluid to both the processing magnetorheological polishing device and the testing magnetorheological polishing device.

[0038] In some embodiments, a magnetorheological polishing apparatus for processing and / or testing magnetorheological polishing includes a magnetorheological polishing assembly, a magnetorheological fluid flow measurement assembly, and a flow control valve. The magnetorheological polishing assembly processes the optical element 3, the magnetorheological fluid flow measurement assembly measures the flow of the magnetorheological fluid in real time during processing, and the flow control valve, controlled by a control system 1, prevents the flow and transport of the magnetorheological fluid.

[0039] In one embodiment, the processing magnetorheological polishing apparatus and the testing magnetorheological polishing apparatus have identical structures. The processing magnetorheological polishing apparatus is rigidly connected to the free end of a robot 2, enabling the robot 2 to drive the processing magnetorheological polishing apparatus toward an optical element 3 placed on a laboratory table 5 and process the optical element 3. The testing magnetorheological polishing apparatus is positioned near the laboratory table 5 by an independent support frame 6, and a position adjustment table 4 is placed within the independent support frame 6. The testing magnetorheological polishing apparatus cooperates with the position adjustment table 4 to process the optical element 3 placed on the position adjustment table 4. The position adjustment table 4 is preferably a three-dimensional adjustment table, enabling the position adjustment table 4 to drive the optical element 3 to move forward, backward, left, right, and up and down in three dimensions, thereby adjusting the position of the optical element 3. Furthermore, a supply system provides magnetorheological fluid to both the processing magnetorheological polishing apparatus and the testing magnetorheological polishing apparatus through pipelines and stop valves, thereby enabling the stop valves to be controlled by a control system 1 to control the flow and delivery of the magnetorheological fluid.

[0040] In some embodiments, a magnetorheological polishing assembly includes a polishing wheel 7, a polishing motor 8, a nozzle 9, and a magnet module 10. The polishing wheel 7 contacts the optical element 3 and processes the optical element 3 in conjunction with the magnetorheological fluid. The polishing motor 8 is controlled by a control system 1 and drives the polishing wheel 7. The nozzle 9 is connected to a supply system and supplies the magnetorheological fluid to the polishing wheel 7. The magnet module 10 modifies the stiffness of the magnetorheological fluid at the polishing wheel 7.

[0041] In one embodiment, the polishing wheel 7, polishing motor 8, nozzle 9, and magnet module 10 are mounted on a magnetorheological support frame 11. In the magnetorheological polishing apparatus used for processing, the magnetorheological support frame 11 is rigidly connected to the free end of the robot 2. In the magnetorheological polishing apparatus used for testing, the magnetorheological support frame 11 is rigidly connected to the independent support frame 6. The output end of the polishing motor 8 is connected to the rotating shaft of the polishing wheel 7 via a transmission belt, enabling the control system 1 to drive the polishing wheel 7 via the polishing motor 8 to process the optical element 3 and adjust the rotational speed of the polishing wheel 7 during processing. The nozzle 9 is mounted on the magnetorheological support frame 11 along the direction of rotation of the polishing wheel 7, so that the nozzle 9 supplies magnetorheological fluid to the working point of the polishing wheel 7. When the magnet module 10 is positioned near the working point of the polishing wheel 7, the magnetic induction intensity of the magnet module 10 changes the stiffness of the magnetorheological fluid at the working point of the polishing wheel 7, thereby enabling the polishing wheel 7 to cooperate with the magnetorheological fluid to process the optical element 3. It should be noted that the working point of the polishing wheel 7 is the point on the polishing wheel 7 at the minimum distance from the optical element 3 when the polishing wheel 7 contacts the optical element 3. In addition, a recovery box 12 for recovering the magnetorheological fluid is installed near the polishing wheel 7. The polishing wheel 7 sends the remaining magnetorheological fluid into the recovery box 12. The recovery box 12 is connected to the supply system through a pipeline to ensure that the recovered magnetorheological fluid can be returned to the supply system to achieve the recycling of the magnetorheological fluid. It should be noted that the installation position of the recovery box 12 must not hinder the normal processing of the polishing wheel 7. The magnet module 10 can be an independent electromagnet whose magnetic induction intensity is changed by current, voltage, etc., or an independent magnet with constant magnetic induction intensity, or a combination of an electromagnet and a magnet, or other forms of magnets that can generate magnetic induction intensity. The present invention does not limit the form and composition of the magnet module 10.

[0042] In some embodiments, the magnetorheological fluid flow measurement assembly includes a pressure sensor 13 and an electromagnetic flowmeter 14. The pressure sensor 13 measures the pressure generated during the flow of the magnetorheological fluid and transmits the measured pressure to the control system 1. The electromagnetic flowmeter 14 measures the flow rate of the magnetorheological fluid and transmits the measured flow rate to the control system 1.

[0043] In one embodiment, the pressure sensor 13 and the electromagnetic flowmeter 14 are connected to the pipeline for conveying the magnetorheological fluid. The pressure sensor 13 measures the pressure of the magnetorheological fluid in the pipeline, and the electromagnetic flowmeter 14 measures the flow rate of the magnetorheological fluid in the pipeline.

[0044] In some embodiments, the supply system includes a liquid storage module 15, a recovery module 16, and a supply module 17. The liquid storage module 15 stores and stirs the magnetorheological fluid; the recovery module 16 is controlled by the control system 1 to recover the magnetorheological fluid and transfer the recovered magnetorheological fluid to the liquid storage module 15; and the supply module 17 is controlled by the control system 1 to transfer the magnetorheological fluid in the liquid storage module 15 to the processing magnetorheological polishing equipment and / or the testing magnetorheological polishing equipment. In one embodiment, the control system 1 controls the recovery speed of the recovery module 16 and the supply speed of the supply module 17. The supply module 17 supplies the magnetorheological fluid in the liquid storage module to the nozzle 9 in the processing magnetorheological polishing equipment and the testing magnetorheological polishing equipment via a pipeline, and also transfers the magnetorheological fluid from the recovery box 12 to the recovery module via a pipeline.

[0045] In a certain embodiment, in order to reduce the overall volume of the magnetorheological removal function change measuring device with a branch design, the liquid storage module 15, the recovery module 16 and the supply module 17 are preferably installed on the robot 2 in the processing magnetorheological polishing system, and in the testing magnetorheological polishing system, the liquid storage module 15, the recovery module 16 and the supply module 17 are preferably installed on an independent support frame 6.

[0046] In some embodiments, the processing magnetorheological polishing system and / or the testing magnetorheological polishing system further includes a force sensor 18 and a line laser measuring instrument 19. The force sensor 18 measures the change in force between the magnetorheological fluid and the optical element 3 in real time, and the line laser measuring instrument 19 measures the change in thickness of the magnetorheological fluid ribbon in real time.

[0047] In one embodiment, both the processing and testing magnetorheological polishing systems further include a force sensor 18 and a line laser measuring instrument 19. The force sensor 18 is preferably a six-dimensional force sensor and is mounted on the magnetorheological support frame 11. By sensing the motion changes of the magnetorheological support frame 11, it detects the change in force between the magnetorheological fluid and the optical element 3 as the fluid passes through the working area. In the processing magnetorheological polishing system, the force sensor 18 is mounted at the connection between the free end of the robot 2 and the magnetorheological support frame 11. In the testing magnetorheological polishing system, the force sensor 18 is mounted at the connection between the independent support frame 6 and the magnetorheological support frame 11. The line laser measuring instrument 19 is mounted on the magnetorheological support frame 11, and its detection position illuminates the working point of the polishing wheel 7, measuring in real time the change in thickness of the ribbon formed by the magnetorheological fluid after it passes through the polishing gap. It should be noted that the polishing gap here refers to the distance between the working point of the polishing wheel 7 and the optical element 3, and the working area of ​​the magnetorheological fluid refers to the area where the polishing wheel 7 processes the optical element 3.

[0048] In some embodiments, the magnetorheological polishing test system further includes a particle size measurement and medium content detection device, which measures the particle size of iron powder and polishing powder in the magnetorheological fluid, as well as the content of iron powder, polishing powder and water in real time.

[0049] A method for measuring changes in a magnetorheological removal function of a branched design, according to an embodiment of the present invention, creates a magnetorheological removal function change measuring device of a branched design, such as Figures 1-3 As shown, including:

[0050] S1: Control the supply system to deliver magnetorheological fluid to the processing magnetorheological polishing system and the testing magnetorheological polishing system, and control the processing magnetorheological polishing system and the testing magnetorheological polishing system to process the optical element to be processed and the testing optical element respectively.

[0051] S2: Real-time monitoring of the changes in the magnetorheological fluid in the magnetorheological polishing system to determine whether the magnetorheological fluid is blocked in the magnetorheological polishing system; if blocked, execute step S3; otherwise, repeat step S2 until the processing of the optical element to be processed is completed.

[0052] In some embodiments, in step S2, the allowable pressure range of the magnetorheological fluid in the magnetorheological polishing system is determined; in the magnetorheological polishing system, if the current pressure of the magnetorheological fluid does not exceed the allowable pressure range, it is determined that magnetorheological fluid blockage has not occurred, and step S2 is repeated; if the current pressure of the magnetorheological fluid exceeds the allowable pressure range, it is determined that magnetorheological fluid blockage has occurred, and step S3 is executed.

[0053] In combination with the magnetorheological removal function change measurement device of the branch design described in the embodiment of the present invention, it can be understood that the pressure sensor 13 is used to measure the pressure generated during the flow of the magnetorheological fluid and determine the allowable range of the pressure P of the magnetorheological fluid in the magnetorheological polishing system [P min ,P max If the current pressure P of the magnetorheological fluid is not within the allowable pressure range [P min ,P max ], that is, P∉[P min ,P max ], it is determined that the magnetorheological fluid is blocked and step S3 is executed; on the contrary, if the current pressure P of the magnetorheological fluid is within the pressure allowable range [P min ,P max ], that is, P∈[P min ,P max ], it is determined that no magnetorheological fluid blockage has occurred, and step S2 is repeated.

[0054] In one embodiment, the current pressure P of the magnetorheological fluid can be compared with the pressure allowable range [P min ,P maxSpecifically, if the current pressure P of the magnetorheological fluid is less than the minimum value P of the pressure allowable range, min , that is, P <P min , it is determined that part of the pipeline before the pressure sensor is blocked; if the current pressure P of the magnetorheological fluid is greater than the maximum value P of the pressure allowable range max , that is, P>P max , it is determined that part of the pipeline after the pressure sensor is blocked.

[0055] In some embodiments, step S2 further includes:

[0056] During the current data collection time, the processing information of the test optical element by the test magnetorheological polishing system and the composition information of the magnetorheological fluid in the test magnetorheological polishing system are monitored.

[0057] In one embodiment, in combination with the magnetorheological removal function change measurement device with a branch design described in an embodiment of the present invention, during the current data acquisition time, while monitoring the processing information of the magnetorheological polishing system on the test optical element and the magnetorheological fluid composition information in the magnetorheological polishing system:

[0058] The processing information includes: using the pressure sensor 13 to measure the pressure P' generated during the flow of the magnetorheological fluid, and the corresponding pressure allowable range is [P' min ,P' max ], P' min Indicates the minimum value of the preset pressure P', P' max Represents the maximum value of the preset pressure P'; the flow rate Q of the magnetorheological fluid is measured by the electromagnetic flowmeter 14, and the corresponding flow rate allowable range is [Q min ,Q max ], Q min Indicates the minimum value of the preset flow rate Q, Q max Indicates the maximum value of the preset flow rate Q; the force sensor 18 is used to measure the change of the force F during processing, and the corresponding force allowable range is [F min ,F max ], F min Indicates the preset minimum value of the processing force F, F max Represents the maximum value of the preset processing force F; the change of the ribbon thickness H formed by the magnetorheological fluid after passing through the polishing gap is measured using a line laser measuring instrument 19, and the corresponding allowable range of the ribbon thickness is [H min ,H max ], H min Indicates the minimum value of the preset ribbon thickness H, H maxIndicates the maximum value of the preset ribbon thickness H. All allowable ranges in the processing information, that is, the maximum and minimum values ​​of each parameter in the processing information, need to be determined according to actual conditions;

[0059] The composition information of the magnetorheological fluid includes: the particle size measurement and medium content detection device is used to measure the particle size D of the iron powder in the magnetorheological fluid. F , polishing powder particle size D C , iron powder content FC and water content MC. Iron powder particle size D F The corresponding allowable range of iron powder particle size is [D Fmin ,D Fmax ], D Fmin Indicates the preset iron powder particle size D F The minimum value of D Fmax Indicates the preset iron powder particle size D F The maximum value of the polishing powder particle size D C The corresponding allowable range of polishing powder particle size is [D Cmin ,D Cmax ], D Cmin Indicates the preset polishing powder particle size D C The minimum value of D Cmax Indicates the preset polishing powder particle size D C The maximum value of the iron powder content FC corresponds to the allowable range of iron powder content [FC min ,FC max ], FC min Indicates the minimum value of the preset iron powder content FC, FC max Indicates the maximum value of the preset iron powder content FC; the moisture content MC corresponds to the allowable range of moisture content [MC min ,MC max ], MC min Indicates the minimum value of the preset moisture content MC, MC max The maximum value of the preset water content MC is represented by . The allowable range of all parameters in the magnetorheological fluid composition information, that is, the maximum value and minimum value of each parameter in the magnetorheological fluid composition information, are determined according to actual conditions.

[0060] According to the current processing information, the removal function information of the optical element to be processed is determined.

[0061] In one embodiment, in the process of determining the removal function information of the optical element to be processed according to the current processing information: the removal function information includes the removal function volume removal rate MRR, and the corresponding removal rate allowable range is [MRR min ,MRR max ], MRR min Represents the minimum removal function volume removal rate, MRR maxRepresents the maximum removal function volume removal rate. Further explanation of the removal rate range selection is given based on the linear material removal theory: The surface shape residual ΔE of the linear material removal theory = E-R0 T, where R0 represents the initial setting removal function, E represents the initial surface error of the optical element, T represents the dwell time, and ΔE represents the surface residual error. Represents convolution calculation. When the removal function R changes to the minimum value R of the removal function min Or remove the maximum value R of the function max , and its corresponding removal function volume removal rate is MRR min or MRR max When the corresponding surface residual becomes the minimum surface residual ΔE min Or the maximum surface residual ΔE max , ΔE min or ΔE max The RMS value of the processing target is compared with the RMS value of the processing target. If RMS(ΔE min ) or RMS(ΔE max ) is equal to the RMS value of the processing target, then the allowable range of removal rate is determined to be [MRR min ,MRR max ].

[0062] The next data collection time for the removal function information and the magnetorheological fluid composition information is determined according to the current removal function information and the magnetorheological fluid composition information.

[0063] In one embodiment, in conjunction with the magnetorheological removal function change measurement device of the branch design described in the embodiment of the present invention, in the process of determining the next data collection time for the removal function information and the magnetorheological fluid composition information based on the current removal function information and the magnetorheological fluid composition information:

[0064] If the measured pressure P', flow Q, force F and ribbon thickness H are all within the corresponding allowable range, that is: P'∈[P' min ,P' max ], Q∈[Q min ,Q max ]、F∈[F min ,F max ] and H∈[H min ,H max], the cumulative time is calculated from the beginning of the processing, and the next data collection time interval is ΔT1. The time interval ΔT1 is usually relatively long, generally tens of hours. During the next data collection time interval ΔT1, the test magnetorheological polishing equipment is used to perform fixed-point processing on the optical element for testing to obtain the true removal function volume removal rate MRR'. In addition, no more than 10 ml of magnetorheological fluid in the test magnetorheological polishing equipment is collected, and the particle size D of the iron powder in the magnetorheological fluid is measured by the particle size measurement and medium content detection device. F , polishing powder particle size D C , iron powder content FC and water content MC. It should be noted that the volume of the collected magnetorheological fluid must not affect the supply and recovery of magnetorheological fluid between the supply system and the processing magnetorheological polishing equipment and the testing magnetorheological polishing equipment, that is, it must not affect the smooth flow of magnetorheological fluid between the processing magnetorheological polishing equipment, the testing magnetorheological polishing equipment and the supply system.

[0065] At the current data collection time, if the measured pressure P', flow Q, force F and ribbon thickness H are all within the corresponding allowable range, that is: P'∈[P' min ,P' max ], Q∈[Q min ,Q max ]、F∈[F min ,F max ] and H∈[H min ,H max ], and further compare the current true removal function volume removal rate MRR', and the magnetorheological fluid composition information:

[0066] (1) If the current magnetorheological fluid composition information is within the corresponding allowable range, and the current true removal function volume removal rate MRR' is within the removal rate allowable range [MRR min ,MRR max ], the next data collection time interval is still ΔT1, that is, the magnetorheological fluid composition information and the true removal function volume removal rate MRR' are collected again after an interval of ΔT1;

[0067] (2) If the current magnetorheological fluid composition information is within the corresponding allowable range, but the current true removal function volume removal rate MRR' is not within the allowable range of removal rate [MRR min ,MRR max ], the next data collection time interval is ΔT2, that is, the magnetorheological fluid composition information and the true removal function volume removal rate MRR' are collected at an interval of ΔT2;

[0068] (3) If any of the current magnetorheological fluid composition information exceeds the corresponding allowable range (i.e. the particle size D of the iron powder F, polishing powder particle size D C , iron powder content FC and water content MC any one of which exceeds the corresponding allowable range), but the current real removal function volume removal rate MRR' is within the removal rate allowable range [MRR min ,MRR max ], the next data collection time interval is ΔT3, that is, the magnetorheological fluid composition information and the true removal function volume removal rate are collected at an interval of ΔT3;

[0069] (4) If any of the current magnetorheological fluid composition information exceeds the corresponding allowable range, and the current true removal function volume removal rate MRR' is not within the allowable range of removal rate [MRR min ,MRR max ], the next data collection time interval is ΔT4, that is, the magnetorheological fluid composition information and the true removal function volume removal rate MRR' are collected at an interval of ΔT4; during the current data collection time, if any one or more of the measured pressure P', flow Q, force F, and ribbon thickness H are not within the corresponding allowable range, the current true removal function volume removal rate MRR' and the magnetorheological fluid composition information are further compared:

[0070] (5) If the current magnetorheological fluid composition information is within the corresponding allowable range, and the current true removal function volume removal rate MRR' is within the removal rate allowable range [MRR min ,MRR max ], the next data collection time interval is ΔT5, that is, the magnetorheological fluid composition information and the true removal function volume removal rate MRR' are collected again after an interval of ΔT5;

[0071] (6) If any of the current magnetorheological fluid composition information exceeds the corresponding allowable range, and the current true removal function volume removal rate MRR' is within the removal rate allowable range [MRR min ,MRR max ], the next data collection time interval is ΔT6, that is, the magnetorheological fluid composition information and the true removal function volume removal rate MRR' are collected at an interval of ΔT6;

[0072] (7) If the current magnetorheological fluid composition information is within the corresponding allowable range, but the current true removal function volume removal rate MRR' is not within the allowable range of removal rate [MRR min ,MRR max ], the next data collection time interval is ΔT7, that is, the magnetorheological fluid composition information and the true removal function volume removal rate MRR' are collected at an interval of ΔT7;

[0073] (8) If any of the current magnetorheological fluid composition information exceeds the corresponding allowable range, and the current true removal function volume removal rate MRR' is not within the allowable range of removal rate [MRR min ,MRR max ], the next data collection time interval is ΔT8, that is, the magnetorheological fluid composition information and the true removal function volume removal rate MRR' are collected at an interval of ΔT8.

[0074] The data collection time interval ΔT1~ΔT8 is determined according to actual conditions.

[0075] The present invention obtains the removal function information of the optical element to be processed by comprehensively measuring the various parameters and removal function changes of the magnetorheological fluid of the magnetorheological polishing system during long-term processing. This provides important data support for judging the shape error distribution of the optical element to be processed after processing, and provides data support for the subsequent virtual processing removal function changes of the optical element to be processed, as well as providing guidance for the selection of processing parameters and processing strategies for further long-term processing.

[0076] S3: Exchange the corresponding blocked pipelines in the processing magnetorheological polishing system and the test magnetorheological polishing system; restart the processing magnetorheological polishing system to process the optical element to be processed; install the cleaned pipelines into the test magnetorheological polishing system; restart the test magnetorheological polishing system to process the test optical element; return to step S2.

[0077] In conjunction with the magnetorheological removal function change measurement device with a branch design described in the embodiment of the present invention, it can be understood that in step S3, the stop valve is controlled to close the pipelines in the processing magnetorheological polishing system and the test magnetorheological polishing system, and the corresponding blocked pipelines in the processing magnetorheological polishing system and the test magnetorheological polishing system are exchanged. After the exchange is completed, the processing magnetorheological polishing system is restarted to process the optical element to be processed, and the blocked pipeline is cleaned. The cleaned pipeline is installed in the test magnetorheological polishing system, and the test magnetorheological polishing system is restarted to process the test optical element, and the process returns to step S2 to monitor the magnetorheological fluid and determine whether the magnetorheological fluid is blocked.

[0078] It should be understood that the various forms of the processes shown above can be used to reorder, add, or delete steps. For example, the steps described in the present disclosure can be performed in parallel, sequentially, or in a different order, as long as the desired results of the technical solutions disclosed in the present disclosure can be achieved. This is not limited herein.

[0079] The above specific embodiments do not limit the scope of protection of the present invention. Those skilled in the art will appreciate that various modifications, combinations, sub-combinations, and substitutions may be made based on design requirements and other factors. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention are intended to be included within the scope of protection of the present invention.

Claims

1. A magnetorheological removal function change measurement device with a branch design, characterized in that: It includes a magnetorheological polishing system for machining, a magnetorheological polishing system for testing, a supply system and a control system; among which: The magnetorheological polishing system includes a robot and a magnetorheological polishing device disposed at the free end of the robot. The control system controls the robot and the magnetorheological polishing device to process the optical element. The magnetorheological polishing device measures the flow of magnetorheological fluid inside the magnetorheological polishing device in real time during the processing and transmits the measurement results to the control system. The test magnetorheological polishing system includes a position adjustment platform and a test magnetorheological polishing device; an optical element is placed on the position adjustment platform, and the control system controls the position adjustment platform to adjust the processing position of the optical element; the control system controls the test magnetorheological polishing device to cooperate with the position adjustment platform to process the optical element, and measures the flow of magnetorheological fluid inside the test magnetorheological polishing device in real time during the processing, and transmits the measurement results to the control system; The supply system is controlled by the control system and simultaneously supplies magnetorheological fluid to the processing magnetorheological polishing device and the testing magnetorheological polishing device; The processing magnetorheological polishing device and / or the testing magnetorheological polishing device include: Magnetorheological polishing components for processing optical components; A magnetorheological fluid flow measurement component for measuring the flow of the magnetorheological fluid during the machining process in real time; a stop valve, controlled by the control system, to control the flow and delivery of the magnetorheological fluid; The magnetorheological fluid flow measurement component comprises: a pressure sensor for measuring the pressure generated during the flow of the magnetorheological fluid and transmitting the measured pressure to the control system; An electromagnetic flowmeter, measuring the flow rate of the magnetorheological fluid and transmitting the measured flow rate to the control system; The processing magnetorheological polishing system and / or the testing magnetorheological polishing system further comprises: a force sensor for measuring the change in force between the magnetorheological fluid and the optical element in real time and transmitting the measured force to the control system; A line laser measuring instrument measures the change in thickness of the ribbon of the magnetorheological fluid in real time and transmits the measured ribbon thickness to the control system.

2. The magnetorheological removal function change measuring device with a branch design according to claim 1 is characterized in that: The magnetorheological polishing component comprises: a polishing wheel, contacting the optical element and cooperating with the magnetorheological fluid to process the optical element; A polishing motor, controlled by the control system, drives the polishing motor; a nozzle connected to the supply system and supplying magnetorheological fluid to the polishing wheel; The magnet module changes the stiffness of the magnetorheological fluid at the polishing wheel.

3. The magnetorheological removal function change measuring device with a branch design according to claim 1 is characterized in that: The test magnetorheological polishing system also includes a particle size measurement and medium content detection device; the particle size measurement and medium content detection device measures the particle size of iron powder and polishing powder in the magnetorheological fluid, as well as the content of iron powder, polishing powder and water in real time, and transmits the measured information to the control system.

4. The magnetorheological removal function change measuring device with a branch design according to claim 1 is characterized in that: The supply system comprises: A liquid storage module, storing and stirring the magnetorheological fluid; a recovery module, controlled by the control system, recovering the magnetorheological fluid and transporting the recovered magnetorheological fluid to the liquid storage module; The supply module is controlled by the control system to deliver the magnetorheological fluid in the liquid storage module to the processing magnetorheological polishing device and / or the testing magnetorheological polishing device.

5. A method for measuring changes in a magnetorheological removal function of a shunt design, according to the magnetorheological removal function of a shunt design according to any one of claims 1 to 4, characterized in that: include: S1: Controlling the supply system to deliver magnetorheological fluid to the processing magnetorheological polishing system and the testing magnetorheological polishing system, and controlling the processing magnetorheological polishing system and the testing magnetorheological polishing system to process the optical element to be processed and the testing optical element respectively; S2: real-time monitoring of changes in the magnetorheological fluid in the magnetorheological polishing system to determine whether a blockage of the magnetorheological fluid occurs in the magnetorheological polishing system; if blockage occurs, executing step S3; otherwise, repeating step S2 until the processing of the optical element to be processed is completed; S3: Exchange the corresponding blocked pipelines in the processing magnetorheological polishing system and the test magnetorheological polishing system, restart the processing magnetorheological polishing system to process the optical element to be processed; install the cleaned pipeline into the test magnetorheological polishing system, restart the test magnetorheological polishing system to process the test optical element; return to step S2.

6. The method for measuring changes in magnetorheological removal function of a shunt design according to claim 5, characterized in that: In step S2, the allowable pressure range of the magnetorheological fluid in the magnetorheological polishing system is determined; in the magnetorheological polishing system, if the current pressure of the magnetorheological fluid does not exceed the allowable pressure range, it is determined that magnetorheological fluid blockage has not occurred, and step S2 is repeated; if the current pressure of the magnetorheological fluid exceeds the allowable pressure range, it is determined that magnetorheological fluid blockage has occurred, and step S3 is executed.

7. The method for measuring changes in magnetorheological removal function of a shunt design according to claim 6, characterized in that: Step S2 further includes: During the current data collection time, monitoring processing information of the test optical element by the test magnetorheological polishing system and composition information of the magnetorheological fluid in the test magnetorheological polishing system; Determining removal function information of the optical element to be processed according to current processing information; According to the current removal function information and the magnetorheological fluid composition information, the next data collection time for the removal function information and the magnetorheological fluid composition information is determined.

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