Magnetorheological machining device and method for adjusting machining posture based on ribbon size

Abstract

The invention relates to the technical field of optical machining, in particular to a magnetorheological machining device and method for adjusting the machining posture based on the ribbon size, and the device comprises a robot, a control unit, a magnetorheological machining module and a ribbon measuring assembly; the magneto-rheological processing module is arranged at the free end of the robot; the robot drives a polishing wheel in the magneto-rheological machining module to machine the optical element with magneto-rheological fluid as a medium, and a ribbon measuring assembly measures the ribbon thickness of the magneto-rheological fluid in the machining process; according to the method, the ribbon measuring assembly is used for measuring the real-time change of the ribbon thickness of magnetorheological fluid in the magnetorheological machining process, then the machining posture is regulated and controlled in real time, and then real-time constant control over the removal function is achieved.

Description

Technical Field

[0001] The present invention belongs to the technical field of optical processing, and particularly relates to a magnetorheological processing device and method for adjusting the processing posture based on ribbon size. Background Technique

[0002] Magnetorheological Finishing (MRF) is an advanced optical manufacturing technology developed in recent years. It has many advantages such as a stable removal function, controllable edge effect, small subsurface damage layer, no copying effect, strong shaping ability, and high processing accuracy. Therefore, the magnetorheological polishing technology has received extensive attention in high-precision optical processing. The existing magnetorheological polishing processing centers mainly integrate magnetorheological processing equipment on numerical control machine tools. However, some deficiencies of numerical control machine tools (such as low degrees of freedom, large floor area, high cost, etc.) limit the deviation of aspherical surfaces and it is difficult to perform precise pose control along the surface normal. In view of these deficiencies of numerical control machine tools, researchers have introduced six-degree-of-freedom industrial robots into the field of optical processing in recent years. Six-degree-of-freedom industrial robots have the advantages of high degrees of freedom, small floor area, large processing range, low cost, etc., making up for the deficiencies of numerical control machine tools. Therefore, when integrating magnetorheological processing equipment on industrial robots, it is theoretically possible to achieve high-precision processing of large-aperture complex-surface optical elements. However, due to the influence of factors such as processing, assembly, load, trajectory planning, and reduction ratio, the end-effector accuracy of the robot is relatively low, and the polishing gap changes greatly during the processing. At the same time, the magnetorheological polishing technology is an optical processing technology with a high degree of certainty of the removal function, and has high requirements for the change of the polishing gap during the polishing process. Generally, the change of the polishing gap in a magnetorheological numerical control processing center is in the order of dozens of micrometers (PV < 0.1 mm), while the trajectory accuracy of common commercial robots is generally in the sub-millimeter to millimeter range, and it cannot meet the requirements of the magnetorheological polishing technology for the change of the polishing gap during high-precision polishing.

[0003] At present, the force-position control method has gradually become a new type of constant-force regulation and polishing control method for robots. A common application method is to place a force sensor between the processing tool and the robot. First, gravity calibration is performed on the force sensor to ensure the accuracy of measurement. The pose error is calculated by measuring the change in force, and then the robot pose error is compensated by means of the robot body or other motion compensation mechanisms to achieve constant-force control. The high-efficiency processing of large-aperture optical elements relies on the magnetorheological processing equipment with large-size polishing wheels, and the weight of the magnetorheological processing module of large-size polishing wheels is generally over a hundred kilograms. However, for a magnetorheological processing module weighing over a hundred kilograms, the force change caused by the robot pose error is only dozens of Newtons. When high-precision processing is required, the force needs to be constant at several Newtons or even a fraction of a Newton. This requires the absolute measurement accuracy of measurement equipment such as force sensors to reach one ten-thousandth, and the force sensor also needs to be in a state of variable speed and variable posture movement. Force sensors that meet these requirements are often extremely expensive, greatly increasing the cost of the equipment. Summary of the Invention

[0004] In view of this, the present invention aims to provide a magnetorheological processing device and method for adjusting the processing posture based on the ribbon size. The thickness of the magnetorheological fluid ribbon is measured by a ribbon measurement component, and the polishing gap is adjusted in a timely manner by a robotic arm, thereby realizing real-time constant control of the removal function. This device does not require the adjustment of the entire magnetorheological polishing module, the disturbance to the running accuracy at the end of the processing equipment is small, and the load of the motion compensation adjustment mechanism is small, making it easy to achieve pose regulation.

[0005] To achieve the above object, the technical solution of the present invention is realized as follows: A magnetorheological processing device for adjusting the processing posture based on the ribbon size, comprising a robot, a control unit, a magnetorheological processing module, and a ribbon measurement component; wherein: the magnetorheological processing module is arranged at the free end of the robot; the robot drives the polishing wheel in the magnetorheological processing module to process the optical element with the magnetorheological fluid as the medium, and during the processing, the ribbon measurement component measures the thickness of the magnetorheological fluid ribbon; the control unit includes: a time calculation module, which calculates the measurement time of the ribbon measurement component and the adjustment time of the magnetorheological processing module, and adjusts the ribbon measurement component and the magnetorheological processing module according to the measurement time and the adjustment time; a conversion relationship module, which fits the ribbon thickness with the polishing gap of the polishing wheel to obtain a first conversion relationship, and fits the ribbon thickness with the polishing wheel position of the polishing wheel to obtain a second conversion relationship; a processing program module, which obtains a processing program according to the removal function obtained by the magnetorheological processing module and imports the processing program into the magnetorheological processing module; a real-time regulation module, which adjusts the pose of the robot according to the first conversion relationship, or adjusts the polishing wheel position according to the second conversion relationship to keep the removal function stable when processing the optical element.

[0006] Furthermore, the ribbon measurement component includes a ribbon measuring device and an adjustment bracket; the ribbon measuring device is arranged on the adjustment bracket; the ribbon measuring device measures the thickness of the ribbon and transmits the measured ribbon thickness to the control unit; the adjustment bracket is controlled by the real-time regulation module and arranged on the magnetorheological processing module for adjusting the position and pose of the ribbon measuring device.

[0007] Furthermore, the magnetorheological processing module further includes a polishing motor, a nozzle, a supply system, a magnet, a real-time adjustment device, and a magnetorheological mounting bracket; wherein, the magnetorheological mounting bracket is arranged on the free end, and the adjustment bracket is arranged on the magnetorheological mounting bracket; the polishing wheel and the real-time adjustment device are arranged on the magnetorheological mounting bracket, and the real-time adjustment device adjusts the position of the polishing wheel; the polishing motor is arranged on the magnetorheological mounting bracket and connected to the polishing wheel to control the polishing wheel to rotate by the polishing motor; the nozzle is arranged on the magnetorheological mounting bracket along the rotation direction of the polishing wheel, and the supply system conveys magnetorheological fluid to the nozzle; the magnet is arranged on the magnetorheological mounting bracket and near the working point of the polishing wheel, so that the magnetorheological fluid changes the stiffness of the magnetorheological fluid under the influence of the magnetic field intensity of the magnet.

[0008] Furthermore, the real-time adjustment device includes a displacement output motor, a ball screw, and a support fixing bracket; wherein, the support fixing bracket is arranged on the magnetorheological mounting bracket, the displacement output motor is arranged on the support fixing bracket, and the displacement output motor is connected to the ball screw arranged on the support fixing bracket; the polishing wheel is connected to the connecting block on the ball screw, and the ball screw drives the polishing wheel to move along the ball screw; the control unit sends a control signal to the displacement output motor, and when the displacement output motor drives the ball screw to rotate, the ball screw drives the polishing wheel to move.

[0009] Furthermore, the adjustment bracket includes a support frame, a longitudinal sliding component, a transverse sliding component, and an axial rotation connecting plate; wherein, one end of the support frame is connected to the magnetorheological mounting bracket; the longitudinal sliding component is arranged on the other end of the support frame, the transverse sliding component is arranged on the longitudinal sliding component, the axial rotation connecting plate is arranged on the transverse sliding component, and the ribbon measuring device is arranged on the axial rotation connecting plate, so that while the axial rotation connecting plate drives the ribbon measuring device to rotate, the longitudinal sliding component and the transverse sliding component drive the ribbon measuring device to move longitudinally and transversely.

[0010] Furthermore, the ribbon measurement component, the robot, and the real-time adjustment device are respectively connected to the control unit to form their respective communication lines, so that the control unit receives and sends signals through the corresponding communication lines.

[0011] A magnetorheological polishing method based on robot pose control, based on the magnetorheological processing device for adjusting the processing pose according to the ribbon size provided by the present invention, includes the following steps: A1: Control the pose of the robot, drive the polishing wheel to process the test optical element with different polishing gaps, and obtain the first conversion relationship in the conversion relationship module; A2: Set the first variable range of the polishing gap, and obtain the corresponding second variable range of the ribbon thickness according to the first conversion relationship; Set the maximum polishing gap, and obtain the corresponding maximum ribbon thickness according to the first conversion relationship; A3: Control the time calculation module to adjust the ribbon measurement component and the magnetorheological processing module in combination with the maximum polishing gap; A4: Combine the second variable range, the maximum polishing gap and the maximum ribbon thickness to process the optical element to be processed. During the processing, the real-time control module adjusts the pose of the robot in real time, and uses the change amount of the polishing gap generated after the adjustment as the input for processing the next processing position, so that the ribbon thickness at the next processing position is within the second variable range.

[0012] Further, in step A1, control the polishing wheel to process the test optical element with different polishing gaps, measure the ribbon thickness in real time through the ribbon measurement component, and fit the first conversion relationship in the conversion relationship module.

[0013] Further, in step A4, when the polishing wheel is controlled to move to the current processing position, the current ribbon thickness measured by the ribbon measurement component is compared with the second variable range : If the current ribbon thickness is within the second variable range , that is , then there is no need to adjust the current pose of the robot; If the current ribbon thickness is not within the second variable range , that is , then the current pose of the robot needs to be adjusted: If the change amount of the current ribbon thickness is greater than or equal to the maximum ribbon thickness change amount , , denotes the maximum ribbon thickness, denotes the initial ribbon thickness, and the pose of the robot is adjusted according to the following formula: ; where, denotes the position at the current processing position of the magnetorheological processing module; denotes the initial position of the magnetorheological processing module, denotes the maximum polishing gap, represents the initial polishing gap; If the change amount of the current ribbon thickness is less than the maximum ribbon thickness change amount , the current polishing gap is adjusted according to the following formula as follows: .

[0014] A magnetorheological polishing method based on the control of the polishing wheel position. According to the magnetorheological processing device for adjusting the processing posture based on the ribbon size provided by the present invention, the method includes the following steps: B1: Control the polishing wheel to process the test optical element with different polishing gaps, and obtain the second conversion relationship in the conversion relationship module; B2: Set the third variable range of the polishing wheel position, and obtain the corresponding fourth variable range of the ribbon thickness according to the second conversion relationship; set the maximum polishing wheel position, and obtain the corresponding maximum ribbon thickness according to the second conversion relationship; B3: Control the time calculation module to adjust the ribbon measurement component and the magnetorheological processing module in combination with the maximum polishing wheel position; B4: Process the optical element to be processed in combination with the third variable range, the maximum polishing wheel position and the maximum ribbon thickness, and during the processing, the real-time regulation module adjusts the polishing wheel position in real time.

[0015] Further, step B1 includes the following steps: B11: Control the polishing wheel to process the test optical element with different polishing gaps, calculate the volume removal rate of the removal function at each processing position, and at the same time, the ribbon measurement component measures the ribbon thickness at each processing position in real time, and fit in the conversion relationship module to obtain: ; wherein, represents the volume removal rate of the removal function and the ribbon thickness the third conversion relationship between them; B12: Under different polishing gaps, separately change the polishing wheel position and process on the test optical element to obtain the volume removal rate of the removal function at each processing position, and then fit in the conversion relationship module to obtain: ; wherein, represents the polishing wheel position and the volume removal rate of the removal function the fourth conversion relationship between them; B13: According to the third conversion relationship and the fourth conversion relationship, obtain through the following formula: ; Among them, represents the second conversion relationship.

[0016] Furthermore, in step B4, when controlling the polishing wheel to move to the current machining position, the current ribbon thickness measured by the ribbon measuring component is compared with the fourth variable range as follows: If the current ribbon thickness is within the fourth variable range , there is no need to adjust the current polishing wheel position ; If the current ribbon thickness is not within the fourth variable range , then the current polishing wheel position needs to be adjusted: If the current ribbon thickness is greater than or equal to the maximum ribbon thickness , the current polishing wheel position is adjusted to the maximum polishing wheel position ; If the current ribbon thickness is less than the maximum ribbon thickness , the current polishing wheel position is adjusted according to the following formula: .

[0017] Compared with the prior art, the present invention can achieve the following beneficial effects: In the magnetorheological processing device and method for adjusting the machining posture based on the ribbon size according to the present invention, the ribbon thickness of the magnetorheological fluid is measured non-contact by the ribbon measuring component. When the magnetorheological processing equipment polishes the test optical element, different polishing gaps and the corresponding ribbon thicknesses are collected. Then, the corresponding relationship between the polishing gap and the ribbon thickness is calculated through the collected polishing gap and ribbon thickness. After that, the optical element to be processed is processed according to the corresponding relationship to obtain the current ribbon thickness. Whether to adjust the polishing gap and the corresponding magnetic field strength is determined by comparing the ribbon thickness, so as to adjust the machining posture in real time. This process does not require calibration steps for parameters such as gravity compensation and is not affected by factors such as the weight of the robot and the magnetorheological processing module of the magnetorheological processing equipment, the running accuracy, running speed, posture, inertia of the equipment itself, and other factors. Only real-time regulation of the machining posture change is performed, and the measurement of the size parameters of the magnetorheological medium ribbon under the coupling of multiple factors during the machining process is realized more comprehensively and accurately, so as to control the polishing gap without the need to rely on other auxiliary running mechanisms and without increasing additional costs. Brief Description of the Drawings

[0018] The drawings forming a part of the present invention are used to provide a further understanding of the present invention. The schematic embodiments and descriptions thereof of the present invention are used to explain the present invention and do not constitute an improper limitation to the present invention. In the drawings: Figure 1 FIG. is a schematic structural view of the magnetorheological processing device based on ribbon size adjustment for processing posture from one perspective according to an embodiment of the present invention; Figure 2 FIG. is a schematic view of the magnetorheological processing device based on ribbon size adjustment for processing posture from another perspective according to an embodiment of the present invention; Figure 3 FIG. is a schematic structural view of the magnetorheological processing module according to an embodiment of the present invention; Figure 4 FIG. is a schematic structural view of the real-time adjustment device according to an embodiment of the present invention; Figure 5 FIG. is a schematic structural view of the ribbon measurement assembly according to an embodiment of the present invention; Figure 6 FIG. is a schematic structural view of the adjustment bracket according to an embodiment of the present invention.

[0019] Description of the Reference Numerals in the Drawings: 1, robot; 2, control unit; 3, magnetorheological processing module; 4, ribbon measurement assembly; 5, polishing wheel; �, experimental bench; 7, optical element to be processed; 8, test optical element; 9, real-time adjustment device; 10, polishing motor; 11, nozzle; 12, magnet; 13, magnetorheological mounting bracket; 14, connecting plate; 15, transmission belt; 16, support fixing bracket; 17, displacement output motor; 18, ball screw; 19, guide rail; 20, ribbon measurement device; 21, adjustment bracket; 22, support frame; 23, longitudinal sliding assembly; 24, transverse sliding assembly; 25, axial rotation connecting plate. Detailed Description of the Embodiments

[0020] In order to make the objectives, technical solutions and advantages of the present invention clearer, the present invention will be further described in detail below with reference to the 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 to the present invention.

[0021] It should be noted that, without conflict, the embodiments in the present invention and the features in the embodiments can be combined with each other.

[0022] In the description of the present invention, it should be understood that the orientation or positional relationship indicated by the terms "center", "longitudinal", "transverse", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc. is based on the orientation or positional relationship shown in the drawings. It is 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. Therefore, it should not be construed as a limitation to the present invention. In addition, the terms "first", "second", etc. are only used for descriptive purposes and cannot be understood as indicating or implying relative importance or implicitly specifying the quantity of the indicated technical features. Thus, the features defined with "first", "second", etc. may explicitly or implicitly include one or more of such features. In the description of the present invention, unless otherwise specified, the meaning of "plural" is two or more.

[0023] In the description of the present invention, it should be noted that unless otherwise clearly specified and defined, the terms "mounted", "connected", and "coupled" should be understood in a broad sense. For example, it may be a fixed connection, a detachable connection, or an integral connection; it may be a mechanical connection or an electrical connection; it may be directly connected or indirectly connected through an intermediate medium, and it may be the communication inside two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood through specific circumstances.

[0024] The present invention will be described in detail below with reference to the drawings and in conjunction with embodiments.

[0025] As Figures 1 to 2 shown, the magnetorheological finishing device based on ribbon size adjustment for machining posture according to the embodiment of the present invention includes a robot 1, a control unit 2, a magnetorheological finishing module 3, and a ribbon measurement component 4. The magnetorheological finishing module 3 is arranged at the free end of the robot 1. The robot 1 drives the polishing wheel 5 in the magnetorheological finishing module 3 to place the optical element 7 or the test optical element 8 to be machined on the experimental table 6 with magnetorheological fluid as the medium for machining. The ribbon measurement component 4 measures the ribbon thickness of the magnetorheological fluid during the machining process.

[0026] Inside the control unit 2, there are a time calculation module, a conversion relationship module, and a real-time regulation module. The time calculation module is used to calculate the measurement time of the ribbon measurement component 4 and the adjustment time of the magnetorheological processing module, and to adjust the ribbon measurement component 4 and the magnetorheological processing module according to the measurement time and the adjustment time. The conversion relationship module is used to fit the ribbon thickness with the polishing gap of the polishing wheel 5 to obtain a first conversion relationship, and to fit the ribbon thickness with the polishing wheel position of the polishing wheel 5 to obtain a second conversion relationship. In the embodiment of the present invention, the polishing wheel position is defined as the distance between the working point of the polishing wheel 5 and the optical element to be processed 7 or the test optical element 8. The working point of the polishing wheel 5 is defined as the closest point along the surface normal direction of the optical element to be processed 7 or the test optical element 8 between the polishing wheel 5 and the surface of the optical element to be processed 7 or the test optical element 8. The processing program module is used to obtain a processing program according to the removal function obtained by the magnetorheological processing module and import the processing program into the magnetorheological processing module. The real-time regulation module is used to adjust the pose of the robot 1 according to the first conversion relationship or adjust the polishing wheel position according to the second conversion relationship to keep the removal function stable when processing the optical element to be processed 7.

[0027] Such as Figures 1 to 3As shown, the magnetorheological processing module 3 further includes a real-time adjustment device 9, a polishing motor 10, a nozzle 11, a supply system, a magnet 12, and a magnetorheological mounting bracket 13. The magnetorheological mounting bracket 13 is installed and fixed on the free end of the robot 1. The polishing wheel 5 and the real-time adjustment device 9 are installed on the magnetorheological mounting bracket, and the real-time adjustment device 9 is connected to the polishing wheel 5. Specifically, the head end of the connecting plate 14 is installed on the real-time adjustment device 9, and the polishing wheel 5 is installed at the tail end of the connecting plate 14. Thus, the connection between the real-time adjustment device 9 and the polishing wheel 5 is completed, enabling the real-time adjustment device 9 to adjust the position of the polishing wheel 5, thereby changing the polishing gap of the polishing wheel 5. The polishing motor 10 is arranged on the magnetorheological mounting bracket 13 and connected to the polishing wheel 5 to control the rotation of the polishing wheel 5. Specifically, the polishing motor 10 is mounted on the connecting plate 14, the output end of the polishing motor 10 passes through the connecting plate 14, the bearing of the polishing wheel 5 passes through the tail end of the connecting plate 14, and the output end of the polishing motor 10 is connected to the bearing of the polishing wheel 5 through a transmission belt 15, enabling the polishing motor 10 to control the rotation of the polishing wheel 5 through the transmission belt 15. In the embodiment of the present invention, the manner in which the polishing motor 10 drives the polishing wheel 5 to rotate can refer to the invention patent application with the Chinese patent publication number CN118322074A, publication date July 12, 2024, and patent name "Self-rotating Polishing Module Processing System". The nozzle 11 is installed on the magnetorheological mounting bracket 13 along the rotation direction of the polishing wheel 5. The supply system conveys magnetorheological fluid to the nozzle 11, and the nozzle 11 sprays the magnetorheological fluid at the working point of the polishing wheel 5, thereby enabling the polishing wheel 5 to process the optical element 7 to be processed or the test optical element 8 with the magnetorheological fluid as the medium. The magnet 12 is fixed on the magnetorheological mounting bracket 13 through the connecting plate 14 and is close to the working point of the polishing wheel 5, causing the magnetorheological fluid to change its stiffness under the influence of the magnetic field intensity of the magnet 12. In addition, in the embodiment of the present invention, the supply system uses the DFLD vertical multi-stage pump of Shanghai Dongfang Pump Industry Co., Ltd.

[0028] The structure of the real-time adjustment device 9 for controlling the polishing wheel 5 is as Figure 4As shown in the figure, it includes a support fixing frame 16, a displacement output motor 17 and a ball screw 18. The support fixing frame 16 is installed on the magnetorheological mounting frame 13, and the displacement output motor 17 is installed on the top of the support fixing frame 16. The screw in the ball screw 18 is installed on the support fixing frame 16 and is connected to the output end of the displacement output motor 17. The polishing wheel 5 is connected to the nut of the ball screw 18 through a connecting plate 14, so that the displacement output motor 17 controls the ball screw 18 to drive the polishing wheel 5 to move. The specific process is that the displacement output motor 17 drives the screw to rotate, and the nut cooperates with the screw to pull the polishing wheel 5 to move along the direction of the screw through the connecting plate 14. In the embodiment of the present invention, in order to ensure that the polishing wheel 5 can move stably along the ball screw 18, preferably, a guide rail 19 is installed on each side of the ball screw 18, and the two guide rails 19 are parallel to the ball screw 18. At this time, the head end of the connecting plate 14 is fixedly connected to the nut and the sliders on the two guide rails 19 at the same time. During the processing, the control unit 2 sends a control signal to the displacement output motor 17, the displacement output motor 17 drives the ball screw 18 to rotate, and the ball screw 18 cooperates with the two guide rails 19 to pull the connecting plate 14, thereby driving the polishing wheel 5 to move stably along the direction of the ball screw 18.

[0029] As Figure 5 shown, the ribbon measuring assembly 4 includes a ribbon measuring device 20 and an adjustment bracket 21. The ribbon measuring device 20 completes the measurement of the ribbon thickness and transmits the measured ribbon thickness to the control unit 2. The adjustment bracket 21 is installed on the magnetorheological mounting frame 13 in the magnetorheological processing module 3 through the connecting plate 14 and is used to control and adjust the position and pose of the ribbon measuring device 20. When the magnetorheological processing equipment is polishing, the ribbon measuring assembly 4 does not contact the optical element. Since the properties of the magnetorheological medium in the magnetic field determine that the magnetorheological medium will undergo elastic deformation after passing through the polishing gap, and the change of the polishing gap will be "copied" to the magnetorheological fluid ribbon after passing through the polishing gap, which is mainly manifested in the change of the ribbon thickness. Therefore, the change of the ribbon thickness of the magnetorheological fluid can reflect the change of the volume removal rate of the removal function.

[0030] In an embodiment of the present invention, the ribbon measuring device 20 preferably uses a line laser measuring instrument to measure the thickness of the ribbon. Specifically, the line laser measuring instrument emits a line beam for measurement on the magnetorheological fluid ribbon. The adjustment bracket 21 includes a support frame 22, a longitudinal sliding assembly 23, a transverse sliding assembly 24, and an axial rotation connecting plate 25. One end of the support frame 22 is connected to the magnetorheological mounting frame 13 through a connecting plate 14. The longitudinal sliding assembly 23 is arranged at the other end of the support frame 22. The transverse sliding assembly 24 is arranged on the longitudinal sliding assembly 23. The axial rotation connecting plate 25 is arranged on the transverse sliding assembly 24. The ribbon measuring device 20 is arranged on the axial rotation connecting plate 25, so that while the axial rotation connecting plate 25 drives the ribbon measuring device 20 to rotate, the longitudinal sliding assembly 23 and the transverse sliding assembly 24 drive the ribbon measuring device 20 to move longitudinally and transversely.

[0031] Specifically, the installation process of the adjustment bracket 21 is as Figure 6 shown in (a)-(c) of Figure 6 , that is, as shown in (a) of Figure 5 , the slide rail of the longitudinal sliding assembly 23 is fixedly installed at the other end of the support frame 22; as shown in (b) of Figure 6 , the slider of the longitudinal sliding assembly 23 is fixedly connected to the slide rail of the transverse sliding assembly 24; as shown in (c) of Figure 6 , the axial rotation connecting plate 25 is fixedly connected to the slider of the transverse sliding assembly 24. At this time, the longitudinal sliding assembly 23 and the transverse sliding assembly 24 can drive the axial rotation connecting plate 25 to move along the directions of the longitudinal sliding assembly 23 and the transverse sliding assembly 24. A rotatable turntable with damping is arranged on the longitudinal sliding assembly 23, and the ribbon measuring device 20 is installed on the rotatable turntable. At this time, the longitudinal sliding assembly 23, the transverse sliding assembly 24, and the axial rotation connecting plate 25 cooperate to complete the pose adjustment of the ribbon measuring device 20.

[0032] The robot 1, the ribbon measuring assembly 4, and the real-time adjustment device 9 are respectively connected to the control unit 2 to form their respective communication lines, so that the control unit 2 receives and sends signals through the corresponding communication lines. Specifically, the control unit 2 receives signals from the ribbon measuring device 20 through the communication line, and the control unit 2 sends a control signal for changing the position of the polishing wheel 5 to the displacement output motor 17 in the real-time adjustment device 9 through the communication line. Since a strong magnetic region is generated around the polishing wheel 5 during the polishing operation, the communication line avoids the strong magnetic region.

[0033] Based on the magnetorheological processing device for adjusting the processing posture based on the ribbon size described in the embodiment of the present invention, the embodiment of the present invention also provides a magnetorheological processing method for adjusting the processing posture based on the ribbon size, including a magnetorheological polishing method based on robot pose control and a magnetorheological polishing method based on polishing wheel position control.

[0034] Specific Embodiment 1: The magnetorheological polishing method based on robot pose control provided in this specific embodiment, according to the magnetorheological processing device for adjusting the processing posture based on ribbon size in the embodiment of the present invention, in combination with Figures 1 to 6 , includes the following steps: A1: Control the pose of the robot 1 to drive the polishing wheel 5 to process the test optical element 8 with different polishing gaps, and obtain the first conversion relationship in the conversion relationship module. In step A1, control the magnetorheological processing module 3 to process the test optical element 8 with different polishing gaps, and measure the ribbon thickness in real time through the ribbon measurement component 4. The following is obtained by fitting in the conversion relationship module: ; Wherein, represents the polishing gap, represents the ribbon thickness, represents the first conversion relationship. In this specific embodiment, control the pose of the robot 1 to drive the polishing wheel 5 to perform fixed-point processing on the test optical element 8 for a period of time with different polishing gaps.

[0035] A2: Set the first variable range of the polishing gap, and obtain the corresponding second variable range of the ribbon thickness according to the first conversion relationship , that is: ; ; Set the maximum polishing gap , and obtain the corresponding maximum ribbon thickness according to the first conversion relationship , that is: ; Wherein, the maximum polishing gap and the first variable range are adaptively set and adjusted according to the actual situation.

[0036] A3: Control the time calculation module to adjust the ribbon measurement component 4 and the magnetorheological processing module 3 in combination with the maximum polishing gap. Step A3 includes the following steps: A31. Statistically analyze b data measured by the ribbon measurement component 4 within a seconds to obtain the time for the ribbon measurement component 4 to measure one point; ; A32. Calculate the time required to adjust the magnetorheological processing module 3 under the maximum polishing gap change : ; Wherein, represents the maximum moving speed of the robot 1, , is the initial polishing gap; A33. Measure the vertical distance from the measurement position of the ribbon measurement component 4 to the working point of the polishing wheel 5 , and calculate the time required for the working point of the polishing wheel 5 according to the vertical distance and the set number of revolutions per second n of the polishing wheel 5: : ; Wherein, represents the radius of the polishing wheel 5, and the number of revolutions per second n of the polishing wheel 5 is adaptively set and adjusted according to the actual situation; A34. Calculate the minimum moving time between two adjacent processing positions of the robot 1 at the maximum moving speed : : ; Wherein, represents the distance between two adjacent processing positions; A35. Calculate whether the condition holds: If the condition holds, there is no need to adjust the ribbon measurement component 4 and the polishing wheel 5; if the condition does not hold, it is necessary to adjust the data sampling frequency of the ribbon measurement component 4 and the number of revolutions per second n of the polishing wheel 5 to make the condition hold; A36. Perform mean filtering processing on the measurement data between every two adjacent processing positions and then output it. At the same time, the number of data for mean filtering needs to satisfy .

[0037] A4: Combine the second variable range, the maximum polishing gap, and the maximum ribbon thickness to process the optical element 7 to be processed. During the processing, the real-time control module makes real-time adjustments to the pose of the robot 1, and uses the change amount of the polishing gap generated after the adjustment as the input for processing the next processing position, so that the ribbon thickness at the next processing position is within the second variable range. The adjustment process is as follows: When controlling the polishing wheel 5 to move to the current processing position, compare the current ribbon thickness measured by the ribbon measurement component 4 with the second variable range : If the current ribbon thickness is within the second variable range , that is, , then there is no need to adjust the current pose of the robot 1; If the current ribbon thickness is not within the second variable range , that is , then it is necessary to adjust the current pose of the robot 1: If the change amount of the current ribbon thickness is greater than or equal to the maximum ribbon thickness change amount , that is , , represents the initial ribbon thickness, and the pose of the robot 1 is adjusted according to the following formula: ; wherein represents the current machining position of the magnetorheological machining module 3; represents the initial position of the magnetorheological machining module 3; If the change amount of the current ribbon thickness is less than the maximum ribbon thickness change amount , that is , the current polishing gap is adjusted according to the following formula: .

[0038] Specific embodiment 2: The magnetorheological polishing method based on polishing wheel position control provided in this specific embodiment, according to the magnetorheological machining device based on ribbon size adjustment of machining posture in the embodiment of the present invention, combined with Figures 1 to 6 , includes the following steps: B1: Control the polishing wheel 5 to machine the test optical element 8 with different polishing gaps, and obtain the second conversion relationship in the conversion relationship module. Step B1 includes the following steps: B11: Control the polishing wheel 5 to machine the test optical element 8 with different polishing gaps, calculate the volume removal rate of the removal function at each machining position, and at the same time the ribbon measurement component 4 measures the ribbon thickness at each machining position in real time, and fits in the conversion relationship module to obtain: ; wherein represents the third conversion relationship between the volume removal rate of the removal function and the ribbon thickness ; in this specific embodiment, specifically, control the polishing wheel 5 to perform fixed-point machining on the test optical element 8 with different polishing gaps for a period of time; B12: Under different polishing gaps, separately change the position of the polishing wheel, and machine on the test optical element 8 to obtain the volume removal rate of the removal function at each machining position, and then fit in the conversion relationship module to obtain: ; Among them, represents the fourth conversion relationship between the position of the polishing wheel and the volumetric removal rate of the removal function; in this specific embodiment, specifically, the position of the polishing wheel is changed alone, and the polishing wheel 5 is controlled to perform fixed-point machining on the test optical element 8 for a period of time; B13: According to the third conversion relationship and the fourth conversion relationship, it is obtained through the following formula: ; Among them, represents the second conversion relationship.

[0039] B2: Set the third variable range of the polishing wheel position , and according to the second conversion relationship obtain the corresponding fourth variable range of the ribbon thickness , that is: ; ; Set the maximum polishing wheel position , and according to the second conversion relationship obtain the corresponding maximum ribbon thickness , that is: ; Among them, the maximum polishing wheel position and the third variable range are adaptively adjusted and set according to the actual situation.

[0040] B3: Control the time calculation module to adjust the ribbon measurement component 4 and the magnetorheological processing module 3 in combination with the maximum polishing wheel position. Step B3 includes the following steps: Step B3 includes the following steps: B31. Statistically analyze b data measured by the ribbon measurement component 4 within a seconds to obtain the time for the ribbon measurement component 4 to measure one point ; ; B32. Calculate the time required to adjust the magnetorheological processing module 3 under the maximum polishing wheel position change amount : ; Among them, represents the highest moving speed of the robot 1; the maximum polishing wheel position change amount , ​Indicates the minimum polishing wheel position, and this value is adaptively adjusted according to the actual situation.

[0041] B33. Measure the vertical distance from the measurement position of the ribbon measurement component 4 to the working point of the polishing wheel 5 , and based on the vertical distance and the set number of revolutions per second n of the polishing wheel 5, calculate the time required for the working point of the polishing wheel 5 : ; Among them, represents the radius of the polishing wheel 5, and the number of revolutions per second n of the polishing wheel 5 is adaptively adjusted and set according to the actual situation; B34. Calculate the minimum movement time between two adjacent processing positions of the robot 1 at the highest moving speed : : ; Among them, represents the distance between two adjacent processing positions; B35. Calculate whether the condition holds: If the condition holds, there is no need to adjust the ribbon measurement component 4 and the polishing wheel 5; if the condition does not hold, it is necessary to adjust the data sampling frequency of the ribbon measurement component 4 and the number of revolutions per second n of the polishing wheel 5 to make the condition hold; B36. Perform mean filtering processing on the measurement data between every two adjacent processing positions and then output it. At the same time, the number of data for mean filtering needs to satisfy .

[0042] B4: Combine the third variable range, the maximum polishing wheel position, and the maximum ribbon thickness to process the optical element to be processed. During the processing, the real-time control module makes real-time adjustments to the polishing wheel position. Specifically, it includes: When controlling the polishing wheel to move to the current processing position, compare the current ribbon thickness measured by the ribbon measurement component with the fourth variable range : If the current ribbon thickness is within the fourth variable range , that is , then there is no need to adjust the current polishing wheel position ; If the current ribbon thickness is not within the fourth variable range , that is , then it is necessary to adjust the current polishing wheel position : If the current ribbon thickness is greater than or equal to the maximum ribbon thickness , that is , adjust the current polishing wheel position to the maximum polishing wheel position ; If the current ribbon thickness is less than the maximum ribbon thickness , that is , adjust the current polishing wheel position according to the following formula: .

[0043] The fitting process in the above two specific embodiments includes but is not limited to importing the discrete data of the polishing gap and the ribbon thickness into Matlab software, and completing data fitting with the polyfit fitting instruction of Matlab software to solve the corresponding relationship between the polishing gap and the ribbon structure size parameters; The Polyfit fitting instruction is a basic general instruction of matlab software. In this way, the corresponding relationship and the corresponding function curve between the polishing gap and the ribbon thickness can be more intuitively seen.

[0044] In this embodiment, the calculation conditions give the corresponding relationship between four time elements, that is: within a single sampling period, robot 1 can adjust the magnetorheological processing equipment so that it moves to the theoretical polishing gap, and then the ribbon measurement component performs the next sampling, avoiding too long sampling period resulting in too slow sampling frequency, making the sampling frequency not match the adjustment speed of robot 1, and the adjustment is not timely, resulting in the inability to know the current state of the second size parameter and affecting the automatic compensation function of the polishing gap.

[0045] Among them, regarding the selection of this parameter has the following meaning: The magnetorheological fluid enters the magnetic field working area driven by the polishing wheel 5. Under the action of the magnetic field, the magnetorheological fluid is transformed into a Bingham fluid with high viscosity and low fluidity. The Bingham fluid is extruded through the polishing gap (the distance between the lowest point of the polishing wheel 5 and the workpiece) to form a ribbon. The ribbon thickness and width will carry the information of the polishing gap, that is, the change amount of the polishing gap is associated with the change amounts of the ribbon thickness and width. Therefore, as long as the change of the ribbon thickness is collected, the change of the polishing gap can be reflected.

[0046] The ribbon thickness and width are measured by the ribbon measuring component 4. To avoid the collision between the ribbon measuring component 4 and the test optical element 8 and the optical element 7 to be processed during the processing, the ribbon measuring component 4 needs to be inclined. There is an angle between the measuring direction of the ribbon measuring component 4 and the horizontal line. This results in the data collected not being the ribbon thickness information at the polishing gap, but the data collected when the magnetic rheological fluid driven by the polishing wheel rotates from the lowest point of the polishing wheel to the measuring range of the ribbon measuring component 4 after a certain time. This time is .

[0047] Assume that if the time is very long and the moving speed of the whole device is very fast, resulting in the completion of the whole processing, but the change in the ribbon thickness is not collected in time, and the purpose of real-time control cannot be achieved during the whole processing. Therefore, the time must be considered.

[0048] It should be understood that various forms of the processes shown above can be used, re-ordered, steps added or deleted. For example, the steps described in the disclosure of the present invention can be executed in parallel, sequentially or in a different order, as long as the desired results of the technical solution disclosed in the present invention can be achieved. No limitation is made herein.

[0049] The above specific embodiments do not constitute a limitation on the protection scope of the present invention. Those skilled in the art should understand that various modifications, combinations, sub-combinations and substitutions can be made according to design requirements and other factors. Any modifications, equivalent substitutions and improvements made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

Claims

1. A magnetorheological processing device based on adjusting the processing attitude according to the ribbon size, characterized in that, It includes a robot, a control unit, a magnetorheological machining module, and a ribbon measurement component; wherein: the magnetorheological machining module is arranged at the free end of the robot; the robot drives a polishing wheel in the magnetorheological machining module to machine an optical element with magnetorheological fluid as the medium, and during the machining process, the ribbon measurement component measures the ribbon thickness of the magnetorheological fluid; The interior of the control unit includes: A time calculation module that calculates the measurement time of the ribbon measurement component and the adjustment time of the magnetorheological machining module, and adjusts the ribbon measurement component and the magnetorheological machining module according to the measurement time and the adjustment time; A conversion relationship module that fits the ribbon thickness with the polishing gap of the polishing wheel to obtain a first conversion relationship, and fits the ribbon thickness with the position of the polishing wheel of the polishing wheel to obtain a second conversion relationship; A machining program module that obtains a machining program according to the removal function obtained by the magnetorheological machining module and imports the machining program into the magnetorheological machining module; A real-time regulation module that adjusts the pose of the robot according to the first conversion relationship, or adjusts the position of the polishing wheel according to the second conversion relationship to keep the removal function stable when machining the optical element.

2. The magnetorheological machining device based on ribbon size adjustment for machining posture according to claim 1, wherein, The ribbon measurement component includes a ribbon measurement device and an adjustment bracket; the ribbon measurement device is arranged on the adjustment bracket; the ribbon measurement device measures the ribbon thickness and transmits the measured ribbon thickness to the control unit; the adjustment bracket is arranged on the magnetorheological machining module and is used to adjust the pose of the ribbon measurement device.

3. The magnetorheological processing device based on ribbon size adjustment for processing attitude according to claim 2, wherein The magnetorheological machining module further includes a polishing motor, a nozzle, a supply system, a magnet, a real-time adjustment device, and a magnetorheological mounting bracket; wherein, The magnetorheological mounting bracket is arranged on the free end, and the adjustment bracket is arranged on the magnetorheological mounting bracket; the polishing wheel and the real-time adjustment device are arranged on the magnetorheological mounting bracket, and the real-time adjustment device adjusts the position of the polishing wheel; The polishing motor is arranged on the magnetorheological mounting bracket and is connected to the polishing wheel, so that the polishing motor controls the polishing wheel to rotate; The nozzle is arranged on the magnetorheological mounting bracket along the rotation direction of the polishing wheel, and the supply system conveys magnetorheological fluid to the nozzle; The magnet is arranged on the magnetorheological mounting bracket, and the magnet is close to the working point of the polishing wheel, so that the magnetorheological fluid is affected by the magnetic field intensity of the magnet to change the stiffness of the magnetorheological fluid.

4. The magnetorheological processing device for adjusting the processing attitude based on the ribbon size according to claim 3, characterized in that, The real-time adjustment device includes a displacement output motor, a ball screw, and a support fixing frame; wherein, the support fixing frame is arranged on the magnetorheological mounting frame, the displacement output motor is arranged on the support fixing frame, and the displacement output motor is connected to the ball screw arranged on the support fixing frame; the polishing wheel is connected to the connecting block on the ball screw, so that the ball screw drives the polishing wheel to move; the control unit sends a control signal to the displacement output motor, and when the displacement output motor drives the ball screw to rotate, the ball screw drives the polishing wheel to move.

5. The magnetorheological processing device based on ribbon size adjustment for processing attitude according to claim 3, characterized in that, The adjustment bracket includes a support frame, a longitudinal sliding component, a transverse sliding component, and an axial rotation connecting plate; wherein, one end of the support frame is connected to the magnetorheological mounting frame; the longitudinal sliding component is arranged at the other end of the support frame, the transverse sliding component is arranged on the longitudinal sliding component, the axial rotation connecting plate is arranged on the transverse sliding component, and the ribbon measuring device is arranged on the axial rotation connecting plate, so that while the axial rotation connecting plate drives the ribbon measuring device to rotate, the longitudinal sliding component and the transverse sliding component drive the ribbon measuring device to move longitudinally and transversely.

6. The magnetorheological processing device for adjusting the processing posture based on the ribbon size according to claim 3, wherein The ribbon measuring component, the robot, and the real-time adjustment device are respectively connected to the control unit to form their respective communication lines, so that the control unit receives and sends signals through the corresponding communication lines.

7. A magnetorheological polishing method based on robot pose control, based on the magnetorheological processing device for adjusting the processing posture based on ribbon size according to any one of claims 1 to 6, characterized in that, It includes the following steps: A1: Control the pose of the robot to drive the polishing wheel to process the test optical element with different polishing gaps, and obtain the first conversion relationship in the conversion relationship module; A2: Set the first variable range of the polishing gap, and obtain the corresponding second variable range of the ribbon thickness according to the first conversion relationship; set the maximum polishing gap, and obtain the corresponding maximum ribbon thickness according to the first conversion relationship; A3: Control the time calculation module to adjust the ribbon measuring component and the magnetorheological processing module in combination with the maximum polishing gap; A4: Combine the second variable range, the maximum polishing gap, and the maximum ribbon thickness to process the optical element to be processed. During the processing, the real-time regulation module adjusts the pose of the robot in real time, and uses the change amount of the polishing gap generated after the adjustment as the input when processing the next processing position, so that the ribbon thickness at the next processing position is within the second variable range.

8. The magnetorheological polishing method based on robot pose control according to claim 7, wherein, In step A1, control the polishing wheel to process the test optical element with different polishing gaps, measure the ribbon thickness in real time through the ribbon measuring component, and fit and obtain the first conversion relationship in the conversion relationship module.

9. The magnetorheological polishing method based on robot pose control according to claim 8, characterized in that, In step A4, when controlling the polishing wheel to move to the current machining position, compare the current ribbon thickness measured by the ribbon measuring assembly with the second variable range as follows: If the current ribbon thickness is within the second variable range then there is no need to adjust the current pose of the robot; If the current ribbon thickness is not within the second variable range then it is necessary to adjust the current pose of the robot: If the change amount of the current ribbon thickness is greater than or equal to the maximum ribbon thickness change amount , , denotes the maximum ribbon thickness, denotes the initial ribbon thickness, and the pose of the robot is adjusted according to the following formula: ； Among them, represents the position of the free end at the current machining position; represents the initial position of the magnetorheological machining module; represents the maximum polishing gap, represents the initial polishing gap; If the change amount of the current ribbon thickness is less than the maximum ribbon thickness change amount , the current polishing gap is adjusted according to the following formula: 。 10. A magnetorheological polishing method based on the position control of a polishing wheel, based on the magnetorheological processing device for adjusting the machining posture based on the ribbon size according to any one of claims 1 to 6, characterized in that, It includes the following steps: B1: Control the polishing wheel to process the test optical element with different polishing gaps, and obtain the second conversion relationship in the conversion relationship module; B2: Set a third variable range for the position of the polishing wheel, and obtain a fourth variable range corresponding to the ribbon thickness according to the second conversion relationship; set the maximum polishing wheel position, and obtain the corresponding maximum ribbon thickness according to the second conversion relationship; B3: Control the time calculation module to adjust the ribbon measurement component and the magnetorheological processing module in combination with the maximum polishing wheel position; B4: Process the optical element to be processed in combination with the third variable range, the maximum polishing wheel position, and the maximum ribbon thickness, and during the processing, the real-time regulation module adjusts the position of the polishing wheel in real time.

11. The magnetorheological polishing method based on the polishing wheel position control according to claim 10, characterized in that, Step B1 includes the following steps: B11: Control the polishing wheel to process the test optical element with different polishing gaps, calculate the volume removal rate of the removal function at each processing position, and at the same time, the ribbon measurement component measures the ribbon thickness at each processing position in real time, and fit in the conversion relationship module to obtain: ； Among them, represents the third conversion relationship between the volume removal rate of the removal function and the ribbon thickness ; B12: Under different polishing gaps, separately change the position of the polishing wheel and process on the test optical element to obtain the volume removal rate of the removal function at each processing position, and then fit in the conversion relationship module to obtain: ； Among them, represents the position of the polishing wheel and the volume removal rate of the removal function for the fourth conversion relationship; B13: According to the third conversion relationship and the fourth conversion relationship, obtain through the following formula: ； Among them, represents the second conversion relationship.

12. The magnetorheological polishing method based on the polishing wheel position control according to claim 11, wherein In step B4, when controlling the polishing wheel to move to the current machining position, compare the currently measured ribbon thickness by the ribbon measuring assembly with the fourth variable range as follows: If the current ribbon thickness is within the fourth variable range , that is , then there is no need to adjust the current position of the polishing wheel ; If the current ribbon thickness is not within the fourth variable range , that is , then the position of the current polishing wheel needs to be adjusted: If the current ribbon thickness is greater than or equal to the maximum ribbon thickness , adjust the current polishing wheel position to the maximum polishing wheel position ; If the current ribbon thickness is less than the maximum ribbon thickness , adjust the current polishing wheel position according to the following formula as follows: 。

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