Magnetorheological polishing system and polishing method based on electromagnetic flowmeter sensing

Abstract

The present invention relates to the field of magnetorheological polishing technology, and more particularly to a magnetorheological polishing system and polishing method based on electromagnetic flowmeter sensing. The system monitors changes in magnetorheological fluid flow during the polishing process using an electromagnetic flowmeter. By controlling the liquid pump speed, actuator group output displacement, liquid pump height, nozzle position, and polishing wheel speed, the system achieves coarse and fine regulation of magnetorheological fluid flow fluctuations. This ensures that the magnetorheological fluid flow fluctuation at each polishing point meets high-precision polishing requirements, ensuring a constant removal function during the polishing process. This system eliminates the need for additional follower devices, reduces equipment costs, minimizes flow rate variations, and stabilizes magnetorheological fluid flow fluctuations.

Description

Technical Field

[0001] The present invention relates to the technical field of magnetorheological polishing, and in particular to a magnetorheological polishing system based on electromagnetic flowmeter sensing and a polishing method thereof. Background Art

[0002] Magnetorheological finishing (MRF) is an advanced optical manufacturing technology developed in recent years. It offers numerous advantages, including a stable removal function, controllable edge effects, minimal subsurface damage, no photocopying, strong reshaping capabilities, and high machining accuracy. Consequently, MRF has garnered widespread attention in high-precision optical processing. Existing MRF techniques primarily integrate MRF modules onto CNC machine tools. The MRF module's supply system primarily utilizes a centrifugal pump as its source. However, using a centrifugal pump as the supply source presents a significant problem: as the nozzle of the MRF module processes the curved surface of an optical component, it moves up and down within the work area along with the tool end of the industrial robot. While the centrifugal pump maintains a constant position, the pressure between the pump and nozzle fluctuates, causing the previously stable MRF to change. This, in turn, alters the removal function and affects the final machining accuracy.

[0003] To address this problem, the currently commonly used method is to add a follower device to keep the vertical distance between the centrifugal pump and the nozzle outlet unchanged. However, this method requires an additional follower device with higher motion performance to keep the vertical distance between the centrifugal pump and the nozzle outlet unchanged at all times. Some solutions even place the follower device on the Z-axis of the CNC machine tool, which undoubtedly increases the motion load and equipment cost of the motion mechanism and reduces the motion performance of the equipment. In addition, the follower device cannot strictly ensure that the vertical distance between the centrifugal pump and the nozzle outlet is constant. Therefore, the height difference between the centrifugal pump and the nozzle often changes at all times, affecting the stability of the magnetorheological fluid in the magnetorheological supply system, causing the removal function to change during the processing, affecting the processing results, and increasing the equipment cost. Summary of the Invention

[0004] The purpose of the present invention is to provide a magnetorheological polishing system and polishing method based on electromagnetic flowmeter sensing, so as to solve the problem in the prior art that even if a follow-up device is added, the removal function cannot be kept constant during the machining process.

[0005] To achieve the above object, the technical solution created by the present invention is implemented as follows:

[0006] A magnetorheological polishing system based on electromagnetic flowmeter sensing, comprising:

[0007] a polishing platform on which the element to be polished and the test polishing element are arranged;

[0008] A polishing assembly includes an industrial robot and a magnetorheological polishing module. The industrial robot is used to drive the magnetorheological polishing module to move to the location of a test polishing element or the location of an element to be polished. The magnetorheological polishing module is used to polish the element to be polished or the test polishing element. The magnetorheological polishing module includes a magnetorheological mounting frame, a polishing wheel, a nozzle, a magnet, an actuator group and a supply device. One end of the actuator group is connected to the magnetorheological mounting frame, and the other end of the actuator group is connected to the tool end of the industrial robot. The polishing wheel, nozzle and magnet are respectively mounted on the magnetorheological mounting frame. The nozzle is used to spray magnetorheological fluid onto the polishing wheel, and the magnet is used to change the stiffness of the magnetorheological fluid. The polishing wheel is used to polish the test polishing element or the element to be polished. The supply device is arranged on one side of the polishing platform and is used to pump magnetorheological fluid into the nozzle.

[0009] An electromagnetic flowmeter is installed on the industrial robot to monitor the flow rate of the magnetorheological fluid at the nozzle outlet;

[0010] The laser tracker is set on one side of the polishing platform and is used in conjunction with the target ball to measure the vertical distance between the nozzle and the liquid pump;

[0011] The computer is used to establish a first conversion relationship between the vertical distance and the liquid pump speed, a second conversion relationship between the polishing gap and the magnetorheological fluid flow rate, a third conversion relationship between the liquid pump height and the magnetorheological fluid flow rate, a fourth conversion relationship between the nozzle position and the magnetorheological fluid flow rate, and a fifth conversion relationship between the polishing wheel speed and the magnetorheological fluid flow rate based on the magnetorheological fluid flow rate monitored by the electromagnetic flowmeter, and adjust the liquid pump speed, the actuator group output displacement, the liquid pump height, the nozzle position, and the polishing wheel speed based on the first conversion relationship to the fifth conversion relationship to maintain a constant removal function for each polishing point of the component to be polished; and the computer is used to establish a sixth conversion relationship between the removal function and the magnetorheological fluid flow rate based on the magnetorheological fluid flow rate monitored by the electromagnetic flowmeter, and obtain a variable removal function set based on the sixth conversion relationship to perform secondary polishing on the component to be polished.

[0012] Furthermore, the supply device includes a liquid pump, a mounting bracket, a mounting plate, a linear guide and a ball screw stepper motor; wherein, the linear guide and the ball screw stepper motor are respectively vertically mounted on the mounting bracket, and the linear guides are distributed on both sides of the ball screw stepper motor, the liquid pump is mounted on the mounting plate, and the mounting plate is respectively connected to the slider of the linear guide and the nut of the ball screw stepper motor.

[0013] Furthermore, the nozzle is installed on the magnetorheological mounting frame through the nozzle adjustment seat, and the position of the nozzle relative to the polishing wheel is adjusted through the nozzle adjustment seat; the nozzle adjustment seat includes a fixing frame, a nozzle adjustment motor, a push plate, a nozzle mounting frame and an arc guide rail; wherein, the fixing frame is installed on the magnetorheological mounting frame, the nozzle adjustment motor and the arc guide rail are respectively installed on the fixing frame, the push plate is installed at the output end of the nozzle adjustment motor, the nozzle mounting frame is respectively connected to the push plate and the slider of the arc guide rail, and the nozzle is installed on the nozzle mounting frame.

[0014] Furthermore, the magnetorheological polishing module further includes a polishing wheel drive device, which includes a driving motor, a motor connecting plate, a driving wheel, a driven wheel and a synchronous belt. The driving motor is installed on the connecting plate, a bearing seat is installed on the connecting plate, a bearing is installed in the bearing seat, the bearing is connected to the polishing wheel, the driven wheel is mounted on the bearing, the driving wheel is mounted on the output end of the driving motor, and the synchronous belt is tensioned on the driven wheel and the driving wheel.

[0015] A magnetorheological polishing method based on adjusting the polishing gap by an actuator is implemented using the magnetorheological polishing system based on electromagnetic flowmeter sensing, comprising the following steps:

[0016] S1: Set the theoretical initial value of the liquid pump speed and the corresponding magnetorheological fluid flow rate at each polishing point of the test polishing element, polish the test polishing element, change the vertical distance between the liquid pump and the nozzle, and measure the magnetorheological fluid flow rate corresponding to different vertical distances using an electromagnetic flowmeter. If the magnetorheological fluid flow rate is different from the set theoretical initial value, adjust the liquid pump speed so that the magnetorheological fluid flow rate is the same as the set theoretical initial value, obtain discrete data of the vertical distance and the liquid pump speed, and obtain the first conversion relationship between the vertical distance and the liquid pump speed through data fitting; wherein, the first conversion relationship is expressed as , Indicates the liquid pump speed, Indicates the vertical distance, Indicates the conversion relationship between vertical distance and liquid pump speed;

[0017] And at each vertical distance, different polishing gaps are set, and the magnetorheological fluid flow corresponding to different polishing gaps at each vertical distance is measured by an electromagnetic flowmeter to obtain discrete data of the polishing gap and the magnetorheological fluid flow at each vertical distance. The second conversion relationship between the polishing gap and the corresponding magnetorheological fluid flow at each vertical distance is obtained by data fitting. The second conversion relationship can be expressed as ,in, Indicates the polishing gap at each vertical distance, Indicates the magnetorheological fluid flow rate corresponding to the polishing gap at each vertical distance, It shows the conversion relationship between the polishing gap and the magnetorheological fluid flow rate at various vertical distances;

[0018] S2: According to the height change of the curved surface of the component to be polished, the liquid pump speed change is calculated based on the first conversion relationship to obtain the theoretical liquid pump speed corresponding to each polishing point of the component to be polished. The component to be polished is polished according to the theoretical liquid pump speed of each polishing point. At the same time, the actual magnetorheological fluid flow rate at the nozzle outlet corresponding to each polishing point is monitored in real time by an electromagnetic flowmeter and sent to the computer; wherein the theoretical liquid pump speed is expressed as ,in, Indicates the theoretical liquid pump speed of each polishing point, i=1, 2, 3...m, m represents the number of polishing points, represents the vertical distance of the i-th polishing point;

[0019] S3: Set the flow fluctuation tolerance range in the computer to determine whether the actual magnetorheological fluid flow at the nozzle outlet corresponding to each polishing point exceeds the set flow fluctuation tolerance range. If it does not exceed, keep the polishing gap of the polishing point unchanged. If it exceeds, control the output displacement of the actuator group and then adjust the polishing gap until the actual magnetorheological fluid flow does not exceed the flow fluctuation tolerance range to maintain the removal function of each polishing point constant.

[0020] Furthermore, when polishing each polishing point of the polishing element, a dwell time is set for each polishing point, which specifically includes the following steps:

[0021] S210: Establishing a measurement coordinate system of the laser tracker so that the measurement coordinate system is parallel to the tool coordinate system of the industrial robot;

[0022] S220: driving the industrial robot to move toward the polishing platform so that the lowest point of the polishing wheel just contacts the polishing platform, placing the target ball at the nozzle outlet, and measuring the Z-axis coordinate Z4 of the target ball at this time;

[0023] S230: Place the target ball on the polishing platform close to the lowest point of the polishing wheel and measure the Z-axis coordinate of the target ball at this time , then the vertical distance between the nozzle and the lowest point of the polishing wheel is The time required for the magnetorheological fluid sprayed from the magnetorheological supply system to reach the lowest point of the polishing wheel is ,in, Indicates the number of revolutions per second of the polishing wheel. Indicates the length of the pipe between the electromagnetic flowmeter and the nozzle. represents the magnetorheological fluid flow rate, Indicates the radius of the polishing wheel.

[0024] Furthermore, when the computer generates the polishing control program, if the dwell time of each polishing point is If the dwell time of a polishing point exists, the generated polishing control program is appropriate. , then extend the dwell time of the polishing point , regenerate the polishing control program so that the dwell time of each polishing point .

[0025] Furthermore, in step S3, the maximum adjustment amount of the output displacement of the actuator group is set in the computer as ;as well as,

[0026] If the actual magnetorheological fluid flow rate at the nozzle outlet corresponding to the current polishing point Within the set flow fluctuation tolerance range Keep the polishing gap of the polishing point unchanged;

[0027] If the actual magnetorheological fluid flow rate at the nozzle outlet corresponding to the current polishing point Not within the set flow fluctuation tolerance range The adjustment amount of the output displacement of the current actuator group , then adjust the output displacement of the current actuator group according to the following formula :

[0028] ;

[0029] If the actual magnetorheological fluid flow rate at the nozzle outlet corresponding to the current polishing point Not within the set flow fluctuation tolerance range The adjustment amount of the output displacement of the current actuator group , then adjust the output displacement of the current actuator group according to the following formula :

[0030] ;

[0031] in, Represents the initial output displacement of the actuator group.

[0032] A magnetorheological polishing method based on liquid pump height adjustment is implemented using the above-mentioned magnetorheological polishing system based on electromagnetic flowmeter sensing, comprising the following steps:

[0033] S1: Set the theoretical initial value of the liquid pump speed and the corresponding magnetorheological fluid flow rate at each polishing point of the test polishing element, polish the test polishing element, change the vertical distance between the liquid pump and the nozzle, and measure the magnetorheological fluid flow rate corresponding to different vertical distances using an electromagnetic flowmeter. If the magnetorheological fluid flow rate is different from the set theoretical initial value, adjust the liquid pump speed so that the magnetorheological fluid flow rate is the same as the set theoretical initial value, obtain discrete data of the vertical distance and the liquid pump speed, and obtain the first conversion relationship between the vertical distance and the liquid pump speed through data fitting; wherein, the first conversion relationship is expressed as , Indicates the liquid pump speed, Indicates the vertical distance, Indicates the conversion relationship between vertical distance and liquid pump speed;

[0034] And at each vertical distance, a different polishing gap is set, a different liquid pump height is set at each polishing gap, and the magnetorheological fluid flow rate corresponding to the different liquid pump heights at each polishing gap is measured by an electromagnetic flowmeter to obtain discrete data of the liquid pump height and the magnetorheological fluid flow rate at each polishing gap. The third conversion relationship between the liquid pump height at each polishing gap and the corresponding magnetorheological fluid flow rate is obtained by data fitting. The third conversion relationship can be expressed as: ,in, Indicates the liquid pump height under each polishing gap, Indicates the magnetorheological fluid flow rate corresponding to the liquid pump height under each polishing gap, It shows the conversion relationship between the liquid pump height and the magnetorheological fluid flow rate at each polishing gap;

[0035] S2: According to the height change of the curved surface of the component to be polished, the liquid pump speed change is calculated based on the first conversion relationship to obtain the theoretical liquid pump speed corresponding to each polishing point of the component to be polished. The component to be polished is polished according to the theoretical liquid pump speed of each polishing point. At the same time, the actual magnetorheological fluid flow rate at the nozzle outlet corresponding to each polishing point is monitored in real time by an electromagnetic flowmeter and sent to the computer; wherein the theoretical liquid pump speed is expressed as ,in, Indicates the theoretical liquid pump speed of each polishing point, i=1, 2, 3...m, m represents the number of polishing points, represents the vertical distance of the i-th polishing point;

[0036] S3: Set the flow fluctuation tolerance range in the computer, and determine whether the actual magnetorheological fluid flow at the nozzle outlet corresponding to each polishing point exceeds the set flow fluctuation tolerance range. If it does not exceed, keep the liquid pump height of the polishing point unchanged. If it exceeds, control the ball screw stepper motor to adjust the liquid pump height of the polishing point until the actual magnetorheological fluid flow does not exceed the flow fluctuation tolerance range, so as to maintain the removal function of each polishing point constant.

[0037] Furthermore, when polishing each polishing point of the polishing element, a dwell time is set for each polishing point, which specifically includes the following steps:

[0038] S210: Establishing a measurement coordinate system of the laser tracker so that the measurement coordinate system is parallel to the tool coordinate system of the industrial robot;

[0039] S220: driving the industrial robot to move toward the polishing platform so that the lowest point of the polishing wheel just contacts the polishing platform, placing the target ball at the nozzle outlet, and measuring the Z-axis coordinate Z4 of the target ball at this time;

[0040] S230: Place the target ball on the polishing platform close to the lowest point of the polishing wheel and measure the Z-axis coordinate of the target ball at this time , then the vertical distance between the nozzle and the lowest point of the polishing wheel is The time required for the magnetorheological fluid sprayed from the magnetorheological supply system to reach the lowest point of the polishing wheel is ,in, Indicates the number of revolutions per second of the polishing wheel. Indicates the length of the pipe between the electromagnetic flowmeter and the nozzle. represents the magnetorheological fluid flow rate, Indicates the radius of the polishing wheel.

[0041] Furthermore, when the computer generates the polishing control program, if the dwell time of each polishing point is If the dwell time of a polishing point exists, the generated polishing control program is appropriate. , then extend the dwell time of the polishing point , regenerate the polishing control program so that the dwell time of each polishing point .

[0042] Furthermore, in step S3, the maximum adjustment amount of the liquid pump height is set in the computer as ;as well as,

[0043] If the actual magnetorheological fluid flow rate at the nozzle outlet corresponding to the current polishing point Within the set flow fluctuation tolerance range Inside, keep the liquid pump height of the polishing point unchanged;

[0044] If the actual magnetorheological fluid flow rate at the nozzle outlet corresponding to the current polishing point Not within the set flow fluctuation tolerance range The current liquid pump height adjustment When the liquid pump height is adjusted according to the following formula: :

[0045] ;

[0046] If the actual magnetorheological fluid flow rate at the nozzle outlet corresponding to the current polishing point Not within the set flow fluctuation tolerance range The current liquid pump height adjustment When the liquid pump height is adjusted according to the following formula: :

[0047] ;

[0048] in, Indicates the initial height of the liquid pump.

[0049] A magnetorheological polishing method based on nozzle position adjustment is implemented using the above-mentioned magnetorheological polishing system based on electromagnetic flowmeter sensing, comprising the following steps:

[0050] S1: Set the theoretical initial value of the liquid pump speed and the corresponding magnetorheological fluid flow rate at each polishing point of the test polishing element, polish the test polishing element, change the vertical distance between the liquid pump and the nozzle, and measure the magnetorheological fluid flow rate corresponding to different vertical distances using an electromagnetic flowmeter. If the magnetorheological fluid flow rate is different from the set theoretical initial value, adjust the liquid pump speed so that the magnetorheological fluid flow rate is the same as the set theoretical initial value, obtain discrete data of the vertical distance and the liquid pump speed, and obtain the first conversion relationship between the vertical distance and the liquid pump speed through data fitting; wherein, the first conversion relationship is expressed as , Indicates the liquid pump speed, Indicates the vertical distance, Indicates the conversion relationship between vertical distance and liquid pump speed;

[0051] And at each vertical distance, a different polishing gap is set, a different nozzle position is set at each polishing gap, and the magnetorheological fluid flow rate corresponding to the different nozzle positions at each polishing gap is measured by an electromagnetic flowmeter to obtain discrete data of the nozzle position and the magnetorheological fluid flow rate at each polishing gap. The fourth conversion relationship between the nozzle position at each polishing gap and the corresponding magnetorheological fluid flow rate is obtained by data fitting. The fourth conversion relationship can be expressed as ,in, Indicates the nozzle position under each polishing gap, Indicates the magnetorheological fluid flow rate corresponding to the nozzle position under each polishing gap, It shows the conversion relationship between the nozzle position and the magnetorheological fluid flow rate at each polishing gap;

[0052] S2: According to the height change of the curved surface of the component to be polished, the liquid pump speed change is calculated based on the first conversion relationship to obtain the theoretical liquid pump speed corresponding to each polishing point of the component to be polished. The component to be polished is polished according to the theoretical liquid pump speed of each polishing point. At the same time, the actual magnetorheological fluid flow rate at the nozzle outlet corresponding to each polishing point is monitored in real time by an electromagnetic flowmeter and sent to the computer; wherein the theoretical liquid pump speed is expressed as ,in, Indicates the theoretical liquid pump speed of each polishing point, i=1, 2, 3...m, m represents the number of polishing points, represents the vertical distance of the i-th polishing point;

[0053] S3: Set the flow fluctuation tolerance range in the computer, and determine whether the actual magnetorheological fluid flow at the nozzle outlet corresponding to each polishing point exceeds the set flow fluctuation tolerance range. If it does not exceed, keep the nozzle position of the polishing point unchanged. If it exceeds, control the nozzle adjustment motor to adjust the nozzle position of the polishing point until the actual magnetorheological fluid flow does not exceed the flow fluctuation tolerance range, so as to maintain the removal function of each polishing point constant.

[0054] Furthermore, when polishing each polishing point of the polishing element, a dwell time is set for each polishing point, which specifically includes the following steps:

[0055] S210: Establishing a measurement coordinate system of the laser tracker so that the measurement coordinate system is parallel to the tool coordinate system of the industrial robot;

[0056] S220: driving the industrial robot to move toward the polishing platform so that the lowest point of the polishing wheel just contacts the polishing platform, placing the target ball at the nozzle outlet, and measuring the Z-axis coordinate Z4 of the target ball at this time;

[0057] S230: Place the target ball on the polishing platform close to the lowest point of the polishing wheel and measure the Z-axis coordinate of the target ball at this time , then the vertical distance between the nozzle and the lowest point of the polishing wheel is The time required for the magnetorheological fluid sprayed from the magnetorheological supply system to reach the lowest point of the polishing wheel is ,in, Indicates the number of revolutions per second of the polishing wheel. Indicates the length of the pipe between the electromagnetic flowmeter and the nozzle. represents the magnetorheological fluid flow rate, Indicates the radius of the polishing wheel.

[0058] Furthermore, when the computer generates the polishing control program, if the dwell time of each polishing point is If the dwell time of a polishing point exists, the generated polishing control program is appropriate. , then extend the dwell time of the polishing point , regenerate the polishing control program so that the dwell time of each polishing point .

[0059] Furthermore, in step S3, the maximum adjustment amount of the nozzle position is set in the computer as ;as well as,

[0060] If the actual magnetorheological fluid flow rate at the nozzle outlet corresponding to the current polishing point Within the set flow fluctuation tolerance range Keep the nozzle position of the polishing point unchanged;

[0061] If the actual magnetorheological fluid flow rate at the nozzle outlet corresponding to the current polishing point Not within the set flow fluctuation tolerance range The current nozzle position adjustment amount When , adjust the current nozzle position according to the following formula :

[0062] ;

[0063] If the actual magnetorheological fluid flow rate at the nozzle outlet corresponding to the current polishing point Not within the set flow fluctuation tolerance range The current nozzle position adjustment amount When , adjust the current nozzle position according to the following formula :

[0064] ;

[0065] in, Indicates the initial position of the nozzle.

[0066] A magnetorheological polishing method based on polishing wheel speed regulation is implemented using the above-mentioned magnetorheological polishing system based on electromagnetic flowmeter sensing, comprising the following steps:

[0067] S1: Set the theoretical initial value of the liquid pump speed and the corresponding magnetorheological fluid flow rate at each polishing point of the test polishing element, polish the test polishing element, change the vertical distance between the liquid pump and the nozzle, and measure the magnetorheological fluid flow rate corresponding to different vertical distances using an electromagnetic flowmeter. If the magnetorheological fluid flow rate is different from the set theoretical initial value, adjust the liquid pump speed so that the magnetorheological fluid flow rate is the same as the set theoretical initial value, obtain discrete data of the vertical distance and the liquid pump speed, and obtain the first conversion relationship between the vertical distance and the liquid pump speed through data fitting; wherein, the first conversion relationship is expressed as , Indicates the liquid pump speed, Indicates the vertical distance, Indicates the conversion relationship between vertical distance and liquid pump speed;

[0068] And at each vertical distance, a different polishing gap is set, a different polishing wheel speed is set at each polishing gap, and the magnetorheological fluid flow corresponding to the different polishing wheel speeds at each polishing gap is measured by an electromagnetic flowmeter to obtain discrete data of the polishing wheel speed and the magnetorheological fluid flow at each polishing gap. The fifth conversion relationship between the nozzle position at each polishing gap and the corresponding magnetorheological fluid flow is obtained by data fitting. The fifth conversion relationship can be expressed as ,in, Indicates the polishing wheel speed at each polishing gap, Indicates the magnetorheological fluid flow rate corresponding to the polishing wheel speed at each polishing gap, It represents the conversion relationship between the polishing wheel speed and the magnetorheological fluid flow rate at each polishing gap;

[0069] S2: According to the height change of the curved surface of the component to be polished, the liquid pump speed change is calculated based on the first conversion relationship to obtain the theoretical liquid pump speed corresponding to each polishing point of the component to be polished. The component to be polished is polished according to the theoretical liquid pump speed of each polishing point. At the same time, the actual magnetorheological fluid flow rate at the nozzle outlet corresponding to each polishing point is monitored in real time by an electromagnetic flowmeter and sent to the computer; wherein the theoretical liquid pump speed is expressed as ,in, Indicates the theoretical liquid pump speed of each polishing point, i=1, 2, 3...m, m represents the number of polishing points, represents the vertical distance of the i-th polishing point;

[0070] S3: Set the flow fluctuation tolerance range in the computer, and determine whether the actual magnetorheological fluid flow at the nozzle outlet corresponding to each polishing point exceeds the set flow fluctuation tolerance range. If it does not exceed, keep the polishing wheel speed of the polishing point unchanged. If it exceeds, control the drive motor to adjust the polishing wheel speed of the polishing point until the actual magnetorheological fluid flow does not exceed the flow fluctuation tolerance range, so as to maintain the removal function of each polishing point constant.

[0071] Furthermore, when polishing each polishing point of the polishing element, a dwell time is set for each polishing point, which specifically includes the following steps:

[0072] S210: Establishing a measurement coordinate system of the laser tracker so that the measurement coordinate system is parallel to the tool coordinate system of the industrial robot;

[0073] S220: driving the industrial robot to move toward the polishing platform so that the lowest point of the polishing wheel just contacts the polishing platform, placing the target ball at the nozzle outlet, and measuring the Z-axis coordinate Z4 of the target ball at this time;

[0074] S230: Place the target ball on the polishing platform close to the lowest point of the polishing wheel and measure the Z-axis coordinate of the target ball at this time , then the vertical distance between the nozzle and the lowest point of the polishing wheel is The time required for the magnetorheological fluid sprayed from the magnetorheological supply system to reach the lowest point of the polishing wheel is ,in, Indicates the number of revolutions per second of the polishing wheel. Indicates the length of the pipe between the electromagnetic flowmeter and the nozzle. represents the magnetorheological fluid flow rate, Indicates the radius of the polishing wheel.

[0075] Furthermore, when the computer generates the polishing control program, if the dwell time of each polishing point is If the dwell time of a polishing point exists, the generated polishing control program is appropriate. , then extend the dwell time of the polishing point , regenerate the polishing control program so that the dwell time of each polishing point .

[0076] Further, in step S3, the maximum adjustment amount of the polishing wheel speed is set in the computer to ;as well as,

[0077] If the actual magnetorheological fluid flow rate at the nozzle outlet corresponding to the current polishing point Within the set flow fluctuation tolerance range Keep the polishing wheel speed of the current polishing point unchanged;

[0078] If the actual magnetorheological fluid flow rate at the nozzle outlet corresponding to the current polishing point Not within the set flow fluctuation tolerance range The current polishing wheel speed adjustment value When the current polishing wheel speed is adjusted according to the following formula :

[0079] ;

[0080] If the actual magnetorheological fluid flow rate at the nozzle outlet corresponding to the current polishing point Not within the set flow fluctuation tolerance range The current polishing wheel speed adjustment value When the current polishing wheel speed is adjusted according to the following formula :

[0081] ;

[0082] in, Indicates the initial rotation speed of the polishing wheel.

[0083] A magnetorheological polishing method based on removal function regulation is implemented using the above-mentioned magnetorheological polishing system based on electromagnetic flowmeter sensing, comprising the following steps:

[0084] S1: Set the theoretical initial value of the magnetorheological fluid flow rate at each polishing point of the test polishing element, polish the test polishing element according to the theoretical initial value of the magnetorheological fluid flow rate, obtain the removal function, and simultaneously measure the theoretical magnetorheological fluid flow rate corresponding to each polishing point of the test polishing element by an electromagnetic flowmeter, and calculate the sixth conversion relationship between the removal function and the theoretical magnetorheological fluid flow rate, wherein the sixth conversion relationship is expressed as , Represents the removal function, Represents the theoretical magnetorheological fluid flow rate at each polishing point of the test polishing element, The sixth conversion relationship between the theoretical magnetorheological fluid flow rate and the removal function at each polishing point of the test polishing element is represented;

[0085] S2: setting a flow fluctuation tolerance range in a computer, performing a first polish on the component to be polished based on the theoretical magnetorheological fluid flow rate, measuring the actual magnetorheological fluid flow rate at the nozzle outlet corresponding to each polishing point of the component to be polished using an electromagnetic flowmeter, and determining whether it exceeds the set flow fluctuation tolerance range. If so, recording the actual magnetorheological fluid flow rate at the polishing point, and after the first polishing of the component to be polished is completed, solving the removal function corresponding to the recorded actual magnetorheological fluid flow rate at each polishing point based on the sixth transformation relationship to obtain a variable removal function set;

[0086] S3: performing secondary polishing on the component to be polished according to the variable removal function set, and determining the polishing amount of each polishing point during the secondary polishing of the component to be polished by using the variable removal function set.

[0087] Compared to existing technologies, the present invention uses an electromagnetic flowmeter to measure changes in the magnetorheological fluid flow rate during the polishing process. By controlling the liquid pump speed, actuator assembly output displacement, liquid pump height, nozzle position, and polishing wheel speed, this method achieves coarse and fine regulation of magnetorheological fluid flow fluctuations. This ensures that the magnetorheological fluid flow fluctuation at each polishing point meets the requirements of high-precision polishing, ensuring a constant removal function. This invention eliminates the need for additional follower devices, reduces equipment costs, minimizes flow rate variations, and stabilizes magnetorheological fluid flow fluctuations. BRIEF DESCRIPTION OF THE DRAWINGS

[0088] Figure 1 A schematic structural diagram of a magnetorheological polishing system based on electromagnetic flowmeter sensing according to an embodiment of the present invention at one viewing angle;

[0089] Figure 2 A schematic structural diagram of the magnetorheological polishing system based on electromagnetic flowmeter sensing according to an embodiment of the present invention from another perspective;

[0090] Figure 3 A schematic structural diagram of the actuator according to an embodiment of the present invention;

[0091] Figure 4 A schematic structural diagram of a supply device according to an embodiment of the present invention;

[0092] Figure 5 This is a schematic structural diagram of the nozzle adjustment seat described in an embodiment of the present invention.

[0093] Figure numerals: polishing platform 1, element to be polished 101, test polishing element 102, industrial robot 201, magnetorheological mounting frame 202, polishing wheel 203, magnet 204, nozzle 205, drive motor 206, active wheel 207, driven wheel 208, synchronous belt 209, transition plate 210, cylinder body 211, A cavity 212, B cavity 213, oil scraper ring 214, connecting plate 215, moving piston 216, liquid pump 217, mounting bracket 218, mounting plate 219, linear guide rail 220, ball screw stepper motor 221, fixing frame 222, nozzle adjustment motor 223, push plate 224, nozzle mounting frame 225, arc guide rail 226, actuator group 227, electromagnetic flowmeter 3, laser tracker 4, target ball 401, computer 5. DETAILED DESCRIPTION

[0094] Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. In the following description, identical modules are denoted by identical reference numerals. In the case of identical reference numerals, their names and functions are also identical. Therefore, their detailed description will not be repeated.

[0095] In order to make the purpose, technical solutions and advantages of the present invention more clearly understood, the present invention will be further described in detail below in conjunction with 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.

[0096] In the first aspect, this embodiment provides a magnetorheological polishing system based on electromagnetic flowmeter sensing, the structure of the device is as follows: Figure 1-Figure 5 As shown, including:

[0097] A polishing platform 1, on which a to-be-polished element 101 and a test polishing element 102 are arranged;

[0098] The polishing assembly includes an industrial robot 201 and a magnetorheological polishing module. The industrial robot 201 is used to drive the magnetorheological polishing module to move to the location of the test polishing element 102 or to drive the magnetorheological polishing module to move to the location of the element to be polished 101; the magnetorheological polishing module is used to polish the element to be polished 101 or the test polishing element 102; the magnetorheological polishing module includes a magnetorheological mounting frame 202, a polishing wheel 203, a magnet 204, a nozzle 205, an actuator group 227, a nozzle adjustment seat, a supply device and a polishing wheel driving device, one end of the actuator group 227 is connected to the magnetorheological mounting frame 202, and the actuator group The other end of 227 is connected to the tool end of the industrial robot 201. The actuator assembly 227 is used to adjust the polishing gap. The magnetorheological mounting frame 202 is installed on the tool end of the industrial robot 201. The polishing wheel drive device is installed on the magnetorheological mounting frame 202 and is used to drive the polishing wheel 203 to rotate and polish the polishing element 101 or the test polishing element 102. The nozzle 205 is installed on the magnetorheological mounting frame 202 through the nozzle adjustment seat and is used to spray magnetorheological fluid onto the polishing wheel 203. The nozzle adjustment seat is used to adjust the position of the nozzle 205. The supply device is provided on one side of the polishing platform and is used to pump magnetorheological fluid into the nozzle 205.

[0099] An electromagnetic flowmeter 3, which is provided on the industrial robot 201 and is used to monitor the flow rate of the magnetorheological fluid at the outlet of the nozzle 205;

[0100] The laser tracker 4 is provided on one side of the polishing platform 1 and is used in conjunction with the target ball 401 to measure the vertical distance between the nozzle 205 and the liquid pump 217 (hereinafter referred to as the vertical distance);

[0101] Computer 5 is used to establish, based on the magnetorheological fluid flow rate monitored by the electromagnetic flowmeter, a first conversion relationship between the vertical distance and the rotational speed of the liquid pump 217, a second conversion relationship between the polishing gap and the magnetorheological fluid flow rate, a third conversion relationship between the height of the liquid pump 217 and the magnetorheological fluid flow rate, a fourth conversion relationship between the position of the nozzle 205 and the magnetorheological fluid flow rate, and a fifth conversion relationship between the rotational speed of the polishing wheel 203 and the magnetorheological fluid flow rate, and to adjust the rotational speed of the liquid pump 217, the output displacement of the actuator group 227, the height of the liquid pump 217, the position of the nozzle 205, and the rotational speed of the polishing wheel 203 according to the first to fifth conversion relationships to maintain a constant removal function at each polishing point of the element to be polished 101; and the computer is used to establish, based on the magnetorheological fluid flow rate monitored by the electromagnetic flowmeter, a sixth conversion relationship between the removal function and the magnetorheological fluid flow rate, and to obtain a variable removal function set based on the sixth conversion relationship to perform a secondary polishing on the element to be polished 101.

[0102] The polishing wheel drive device includes a driving motor 206, a driving wheel 207, a driven wheel 208, and a synchronous belt 209. The driving motor 206 is installed on the magnetorheological mounting frame 202. A bearing seat is installed on the magnetorheological mounting frame 202. A bearing is installed in the bearing seat. The bearing is connected to the polishing wheel 203. The driven wheel 208 is mounted on the bearing. The driving wheel 207 is mounted on the output end of the driving motor 206. The synchronous belt 209 is tensioned on the driven wheel 208 and the driving wheel 207. The polishing wheel 203 is driven to rotate by the driving motor 206. Please refer to the Chinese patent with a publication date of July 12, 2024 and publication number CN118322074A.

[0103] Actuator assembly 227 consists of two cascaded high-frequency actuators, with one high-frequency actuator mounted on the output of the other. This results in a total output displacement of actuator assembly 227 equal to the sum of the output displacements of the two high-frequency actuators. In this embodiment of the present invention, the high-frequency actuators are preferably SG-type hydrostatic linear cylinders manufactured by Jilin Huakong Testing Instrument Co., Ltd. Both high-frequency actuators have the same structure, including a transition plate 210, a cylinder body 211, a cavity A 212, a cavity B 213, an oil scraper ring 214, a connecting plate 215, and a moving piston 216. The transition plate 210 is used to connect the tool end of the industrial robot 201 and the cylinder body 211, the A cavity 212 and the B cavity 213 are used to control the inlet and outlet of the hydraulic oil, the oil scraper ring 214 is used to prevent the hydraulic oil from flowing out of the cylinder body 211, the moving piston 216 is used for position output, and the connecting plate 215 is used to connect the moving piston 216 with the magnetorheological polishing module or another high-frequency actuator, thereby outputting the displacement to the magnetorheological polishing module or another high-frequency actuator.

[0104] The supply device includes a liquid pump 217, a mounting bracket 218, a mounting plate 219, a linear guide 220, and a ball screw stepper motor 221. The linear guide 220 and ball screw stepper motor 221 are vertically mounted on the mounting bracket 218, with the linear guides 220 located on either side of the ball screw stepper motor 221. The liquid pump 217 is mounted on the mounting plate 219, which is connected to the slider of the linear guide 220 and the nut of the ball screw stepper motor 221. The height of the liquid pump 217 is adjusted by the ball screw stepper motor 221. The liquid pump 217 uses a CFLC vertical multi-stage pump from Shanghai Dongfang Pump Industry Co., Ltd.

[0105] The nozzle adjustment base includes a fixed frame 222, a nozzle adjustment motor 223, a push plate 224, a nozzle mounting frame 225, and an arc-shaped guide rail 226. The fixed frame 222 is mounted on the magnetorheological mounting frame 202. The fixed frame 230 has an L-shaped structure. The nozzle adjustment motor 223 and the arc-shaped guide rail 226 are respectively mounted on two perpendicular parts of the fixed frame 222, and the length direction of the arc-shaped guide rail 226 is the extension and contraction direction of the nozzle adjustment motor 223. The push plate 224 is mounted on the output end of the nozzle adjustment motor 223. One end of the nozzle mounting frame 225 is connected to the sliders of the push plate 224 and the arc-shaped guide rail 226 respectively, and the other end of the nozzle mounting frame 225 is used to mount the nozzle 205. The nozzle adjustment motor 223 drives the nozzle 205 to move, thereby adjusting the distance between the nozzle 205 and the polishing wheel 203.

[0106] It is worth noting that there is a strong magnetic phenomenon in the working area where the magnetorheological polishing module is located. The connections of various circuits need to avoid the working area to prevent the wires from being adsorbed on the magnetorheological polishing module and affecting normal operation.

[0107] In a second aspect, this embodiment further provides a magnetorheological polishing method for adjusting the polishing gap based on an actuator, which is implemented using the magnetorheological polishing system based on electromagnetic flowmeter sensing, and includes the following steps:

[0108] S1: Set the theoretical initial value of the liquid pump speed and the corresponding magnetorheological fluid flow rate at each polishing point of the test polishing element, polish the test polishing element, change the vertical distance between the liquid pump and the nozzle, and measure the magnetorheological fluid flow rate corresponding to different vertical distances using an electromagnetic flowmeter. If the magnetorheological fluid flow rate is different from the set theoretical initial value, adjust the liquid pump speed so that the magnetorheological fluid flow rate is the same as the set theoretical initial value, obtain discrete data of the vertical distance and the liquid pump speed, and obtain the first conversion relationship between the vertical distance and the liquid pump speed through data fitting; wherein, the first conversion relationship is expressed as , Indicates the liquid pump speed, Indicates the vertical distance, Indicates the conversion relationship between vertical distance and liquid pump speed;

[0109] And at each vertical distance, different polishing gaps are set, and the magnetorheological fluid flow corresponding to different polishing gaps at each vertical distance is measured by an electromagnetic flowmeter to obtain discrete data of the polishing gap and the magnetorheological fluid flow at each vertical distance. The second conversion relationship between the polishing gap and the corresponding magnetorheological fluid flow at each vertical distance is obtained by data fitting. The second conversion relationship can be expressed as ,in, Indicates the polishing gap at each vertical distance, Indicates the magnetorheological fluid flow rate corresponding to the polishing gap at each vertical distance, It shows the conversion relationship between the polishing gap and the magnetorheological fluid flow rate at various vertical distances.

[0110] The purpose of step S1 is to use the electromagnetic flowmeter to establish a first conversion relationship between the vertical distance and the liquid pump speed and a second conversion relationship between the polishing gap and the corresponding magnetorheological fluid flow rate at each vertical distance, as follows:

[0111] The theoretical initial value of the liquid pump speed and the theoretical initial value of the corresponding magnetorheological fluid flow rate are set for each polishing point of the test polishing element, the vertical distance between the liquid pump and the nozzle is set to at least 10 different values, and the magnetorheological fluid flow rate corresponding to different vertical distances is measured using an electromagnetic flowmeter. If the magnetorheological fluid flow rate is different from the set theoretical initial value, the liquid pump speed is adjusted so that the magnetorheological fluid flow rate is the same as the set theoretical initial value, and discrete data of the vertical distance and the liquid pump speed are obtained. The data are then fitted using Matlab's Polyfit command (a basic general command of Matlab software) to obtain a first transformation relationship;

[0112] At each vertical distance, the polishing gap is set to at least 10 sets of different values. The polishing gap and the corresponding magnetorheological fluid flow at different vertical distances are measured by an electromagnetic flowmeter to obtain discrete data of the polishing gap and the corresponding magnetorheological fluid flow at each vertical distance. The Polyfit command of Matlab (this command is a basic general command of Matlab software) is used to fit the data to obtain the second transformation relationship.

[0113] S2: According to the height change of the curved surface of the component to be polished, the liquid pump speed change is calculated based on the first conversion relationship to obtain the theoretical liquid pump speed corresponding to each polishing point of the component to be polished. The component to be polished is polished according to the theoretical liquid pump speed of each polishing point. At the same time, the actual magnetorheological fluid flow rate at the nozzle outlet corresponding to each polishing point is monitored in real time by an electromagnetic flowmeter and sent to the computer; wherein the theoretical liquid pump speed is expressed as ,in, Indicates the theoretical liquid pump speed of each polishing point, i=1, 2, 3...m, m represents the number of polishing points, Represents the vertical distance of the i-th polishing point.

[0114] The height change of the curved surface of the element to be polished reflects the change in the vertical distance between the liquid pump and the nozzle. According to the height of each polishing point on the curved surface of the element to be polished, the theoretical liquid pump speed of each polishing point is calculated using the first conversion relationship. The liquid pump speed is adjusted in real time according to the theoretical liquid pump speed of each polishing point to complete the coarse adjustment of the magnetorheological fluid flow change of the entire curved surface with a large range of high and low movements when the polishing system is polishing the element to be polished.

[0115] Since the magnetorheological fluid measured by the electromagnetic flowmeter needs to be transported through the pipeline and driven by the polishing wheel to reach the working area of ​​the polishing wheel, the magnetorheological fluid at the current flow rate needs to wait for a period of time to reach the working area of ​​the polishing wheel. In order to ensure the adjustment of the removal function change at each polishing point, it is necessary to set the residence time of the polishing point. The specific setting method is as follows:

[0116] S210: Establishing a measurement coordinate system of the laser tracker so that the measurement coordinate system is parallel to the tool coordinate system of the industrial robot.

[0117] S220: Drive the industrial robot to move toward the experimental table so that the lowest point of the polishing wheel just contacts the experimental table, place the target ball of the laser tracker at the nozzle outlet and measure the Z-axis coordinate Z4 of the target ball at this time.

[0118] S230: Place the target ball on the polishing platform close to the lowest point of the polishing wheel and measure the Z-axis coordinate of the target ball at this time , then the vertical distance between the nozzle and the lowest point of the polishing wheel is , To place the target ball on the nozzle to measure the Z-axis coordinate, the time required for the magnetorheological fluid sprayed by the magnetorheological supply system to reach the lowest point of the polishing wheel is ,in, Indicates the number of revolutions per second of the polishing wheel. Indicates the length of the pipe between the electromagnetic flowmeter and the nozzle. represents the magnetorheological fluid flow rate, Indicates the radius of the polishing wheel.

[0119] When the computer generates the polishing control program, if the dwell time of each polishing point is If the dwell time of a polishing point exists, the generated polishing control program is appropriate. , then extend the dwell time of the polishing point , regenerate the polishing control program so that the dwell time of each polishing point .

[0120] S3: Set the flow fluctuation tolerance range in the computer to determine whether the actual magnetorheological fluid flow at the nozzle outlet corresponding to each polishing point exceeds the set flow fluctuation tolerance range. If it does not exceed, keep the polishing gap of the polishing point unchanged. If it exceeds, control the output displacement of the actuator group and then adjust the polishing gap until the actual magnetorheological fluid flow does not exceed the flow fluctuation tolerance range to maintain the removal function of each polishing point constant.

[0121] Since optical component polishing is a variable-speed motion of the polishing system, the movement speed between two adjacent polishing points is often different. In the process from one polishing point to the next, there is often a mismatch between the theoretical polishing position and the actual polishing position, the magnetorheological fluid flow fluctuates, and the removal function changes.

[0122] Therefore, it is necessary to set the tolerance range of the magnetorheological fluid flow fluctuation during the polishing process in the computer. , is the lower limit of the magnetorheological fluid flow fluctuation, is the upper limit of magnetorheological fluid flow fluctuation.

[0123] During the polishing process, the actual magnetorheological fluid flow rate at the nozzle outlet corresponding to each polishing point is measured in real time by an electromagnetic flowmeter. If the measured actual magnetorheological fluid flow rate is If the actual magnetorheological fluid flow rate is not within the range, the magnetorheological fluid flow fluctuation meets the requirements of high-precision polishing, and the measurement data does not need to be output. If the magnetorheological fluid flow fluctuation is within the range, it does not meet the requirements of high-precision polishing. The measurement data needs to be output to the computer for processing, and the computer-processed data is sent to the industrial robot. Finally, the magnetorheological fluid flow change is regulated by adjusting the output displacement of the actuator group to maintain the removal function constant.

[0124] In order to ensure the safety of polishing, the maximum adjustment amount of the output displacement of the actuator group needs to be set in the computer. , place the component to be polished on the polishing platform and fix it, drive the polishing system to polish the component to be polished, and use the electromagnetic flowmeter to measure the actual magnetorheological fluid flow at the nozzle outlet .

[0125] If the actual magnetorheological fluid flow rate at the nozzle outlet corresponding to the current polishing point Within the set flow fluctuation tolerance range Keep the polishing gap of the polishing point unchanged;

[0126] If the actual magnetorheological fluid flow rate at the nozzle outlet corresponding to the current polishing point Not within the set flow fluctuation tolerance range The adjustment amount of the output displacement of the current actuator group , then adjust the output displacement of the current actuator group according to the following formula :

[0127] ;

[0128] If the actual magnetorheological fluid flow rate at the nozzle outlet corresponding to the current polishing point Not within the set flow fluctuation tolerance range The adjustment amount of the output displacement of the current actuator group , then adjust the output displacement of the current actuator group according to the following formula :

[0129] ;

[0130] in, Indicates the set initial output displacement of the actuator group.

[0131] By adjusting the output displacement of the actuator group and changing the polishing gap between the polishing wheel and the element to be polished, precise adjustment of the magnetorheological fluid flow rate in a small range is achieved, so that the magnetorheological fluid flow fluctuation at each polishing point meets the requirements of high-precision polishing, ensuring the constancy of the removal function during the polishing process.

[0132] Compared with the current mainstream real-time control scheme of flow change of magnetorheological fluid supply system based on follow-up device, the present invention uses electromagnetic flowmeter to measure the flow change of polishing system during polishing process and realizes coarse and fine two-stage adjustment of flow fluctuation by controlling the speed of liquid pump and the output displacement of actuator group, thereby realizing real-time control of removal function change. The present invention does not require additional follow-up device, has lower equipment cost, small flow change, and more stable magnetorheological fluid flow fluctuation.

[0133] In a third aspect, this embodiment further provides a magnetorheological polishing method based on liquid pump height adjustment, which is implemented using the above-mentioned magnetorheological polishing system based on electromagnetic flowmeter sensing, and includes the following steps:

[0134] S1: Set the theoretical initial value of the liquid pump speed and the corresponding magnetorheological fluid flow rate at each polishing point of the test polishing element, polish the test polishing element, change the vertical distance between the liquid pump and the nozzle, and measure the magnetorheological fluid flow rate corresponding to different vertical distances using an electromagnetic flowmeter. If the magnetorheological fluid flow rate is different from the set theoretical initial value, adjust the liquid pump speed so that the magnetorheological fluid flow rate is the same as the set theoretical initial value, obtain discrete data of the vertical distance and the liquid pump speed, and obtain the first conversion relationship between the vertical distance and the liquid pump speed through data fitting; wherein, the first conversion relationship is expressed as , Indicates the liquid pump speed, Indicates the vertical distance, Indicates the conversion relationship between vertical distance and liquid pump speed;

[0135] And at each vertical distance, a different polishing gap is set, a different liquid pump height is set at each polishing gap, and the magnetorheological fluid flow rate corresponding to the different liquid pump heights at each polishing gap is measured by an electromagnetic flowmeter to obtain discrete data of the liquid pump height and the magnetorheological fluid flow rate at each polishing gap. The third conversion relationship between the liquid pump height at each polishing gap and the corresponding magnetorheological fluid flow rate is obtained by data fitting. The third conversion relationship can be expressed as: ,in, Indicates the liquid pump height under each polishing gap, Indicates the magnetorheological fluid flow rate corresponding to the liquid pump height under each polishing gap, It shows the conversion relationship between the liquid pump height and the magnetorheological fluid flow rate at each polishing gap.

[0136] Under different polishing gaps and vertical distances, the removal function is kept constant by changing the height of the liquid pump, and then various data are collected to obtain the third conversion relationship between the liquid pump at different heights and the corresponding magnetorheological fluid flow rate under each complete polishing gap, which facilitates subsequent parameter adjustment.

[0137] Different polishing gaps mean that the relative distance between the polishing wheel and the magnet remains unchanged, while the distance between the entire magnetorheological polishing module and the experimental polishing element changes.

[0138] The purpose of step S1 is to use the electromagnetic flowmeter to establish a first conversion relationship between the vertical distance and the liquid pump speed and a third conversion relationship between the liquid pump height and the corresponding magnetorheological fluid flow rate under each polishing gap, as follows:

[0139] The theoretical initial value of the liquid pump speed and the theoretical initial value of the corresponding magnetorheological fluid flow rate are set for each polishing point of the test polishing element, the vertical distance between the liquid pump and the nozzle is set to at least 10 different values, and the magnetorheological fluid flow rate corresponding to different vertical distances is measured using an electromagnetic flowmeter. If the magnetorheological fluid flow rate is different from the set theoretical initial value, the liquid pump speed is adjusted so that the magnetorheological fluid flow rate is the same as the set theoretical initial value, and discrete data of the vertical distance and the liquid pump speed are obtained. The data are then fitted using Matlab's Polyfit command (a basic general command of Matlab software) to obtain a first transformation relationship;

[0140] At each polishing gap, the liquid pump height is set to at least 10 different values. The liquid pump height and the corresponding magnetorheological fluid flow rate at different polishing gaps are measured by an electromagnetic flowmeter to obtain discrete data of the liquid pump height and the corresponding magnetorheological fluid flow rate at each polishing gap. The Polyfit command of Matlab (this command is a basic general command of Matlab software) is used to fit the data to obtain the third transformation relationship.

[0141] S2: According to the height change of the curved surface of the component to be polished, the liquid pump speed change is calculated based on the first conversion relationship to obtain the theoretical liquid pump speed corresponding to each polishing point of the component to be polished. The component to be polished is polished according to the theoretical liquid pump speed of each polishing point. At the same time, the actual magnetorheological fluid flow rate at the nozzle outlet corresponding to each polishing point is monitored in real time by an electromagnetic flowmeter and sent to the computer; wherein the theoretical liquid pump speed is expressed as ,in, Indicates the theoretical liquid pump speed of each polishing point, i=1, 2, 3...m, m represents the number of polishing points, Represents the vertical distance of the i-th polishing point.

[0142] The height change of the curved surface of the element to be polished reflects the change in the vertical distance between the liquid pump and the nozzle. According to the height of each polishing point on the curved surface of the element to be polished, the theoretical liquid pump speed of each polishing point is calculated using the first conversion relationship. The liquid pump speed is adjusted in real time according to the theoretical liquid pump speed of each polishing point to complete the coarse adjustment of the magnetorheological fluid flow change of the entire curved surface with a large range of high and low movements when the polishing system is polishing the element to be polished.

[0143] Since the magnetorheological fluid measured by the electromagnetic flowmeter needs to be transported through the pipeline and driven by the polishing wheel to reach the working area of ​​the polishing wheel, the magnetorheological fluid at the current flow rate needs to wait for a period of time to reach the working area of ​​the polishing wheel. In order to ensure the adjustment of the removal function change at each polishing point, it is necessary to set the residence time of the polishing point. The specific setting method is as follows:

[0144] S210: Establishing a measurement coordinate system of the laser tracker so that the measurement coordinate system is parallel to the tool coordinate system of the industrial robot.

[0145] S220: Drive the industrial robot to move toward the experimental table so that the lowest point of the polishing wheel just contacts the experimental table, place the target ball of the laser tracker at the nozzle outlet and measure the Z-axis coordinate Z4 of the target ball at this time.

[0146] S230: Place the target ball on the polishing platform close to the lowest point of the polishing wheel and measure the Z-axis coordinate of the target ball at this time , then the vertical distance between the nozzle and the lowest point of the polishing wheel is The time required for the magnetorheological fluid sprayed from the magnetorheological supply system to reach the lowest point of the polishing wheel is ,in, Indicates the number of revolutions per second of the polishing wheel. Indicates the length of the pipe between the electromagnetic flowmeter and the nozzle. represents the magnetorheological fluid flow rate, Indicates the radius of the polishing wheel.

[0147] When the computer generates the polishing control program, if the dwell time of each polishing point is If the dwell time of a polishing point exists, the generated polishing control program is appropriate. , then extend the dwell time of the polishing point , regenerate the polishing control program so that the dwell time of each polishing point .

[0148] S3: Set the flow fluctuation tolerance range in the computer, and determine whether the actual magnetorheological fluid flow at the nozzle outlet corresponding to each polishing point exceeds the set flow fluctuation tolerance range. If it does not exceed, keep the liquid pump height of the polishing point unchanged. If it exceeds, control the ball screw stepper motor to adjust the liquid pump height of the polishing point until the actual magnetorheological fluid flow does not exceed the flow fluctuation tolerance range, so as to maintain the removal function of each polishing point constant.

[0149] Since optical component polishing is a variable-speed motion of the polishing system, the movement speed between two adjacent polishing points is often different. In the process from one polishing point to the next, there is often a mismatch between the theoretical polishing position and the actual polishing position, the magnetorheological fluid flow fluctuates, and the removal function changes.

[0150] Therefore, it is necessary to set the tolerance range of the magnetorheological fluid flow fluctuation during the polishing process in the computer. , is the lower limit of the magnetorheological fluid flow fluctuation, is the upper limit of magnetorheological fluid flow fluctuation.

[0151] During the polishing process, the actual magnetorheological fluid flow rate at the nozzle outlet corresponding to each polishing point is measured in real time by an electromagnetic flowmeter. If the measured actual magnetorheological fluid flow rate is The measured data does not need to be output and processed. If the actual measured magnetorheological fluid flow value is not If the magnetorheological fluid flow fluctuation is within the specified range, it does not meet the requirements of high-precision polishing. The measurement data needs to be output to the computer for processing, and the computer-processed data is sent to the ball screw stepper motor. Finally, the magnetorheological fluid flow change is regulated by adjusting the height of the liquid pump to maintain the removal function constant.

[0152] In order to ensure the safety of polishing, the maximum adjustment amount of the liquid pump height needs to be set in the computer. , place the component to be polished on the polishing platform and fix it, drive the polishing system to polish the component to be polished, and use the electromagnetic flowmeter to measure the actual magnetorheological fluid flow at the nozzle outlet .

[0153] If the actual magnetorheological fluid flow rate at the nozzle outlet corresponding to the current polishing point Within the set flow fluctuation tolerance range [FL1, FL2], keep the liquid pump height at the polishing point unchanged;

[0154] If the actual magnetorheological fluid flow rate at the nozzle outlet corresponding to the current polishing point Within the set flow fluctuation tolerance range Inside, keep the liquid pump height of the polishing point unchanged;

[0155] If the actual magnetorheological fluid flow rate at the nozzle outlet corresponding to the current polishing point Not within the set flow fluctuation tolerance range The current liquid pump height adjustment When the liquid pump height is adjusted according to the following formula: :

[0156] ;

[0157] If the actual magnetorheological fluid flow rate at the nozzle outlet corresponding to the current polishing point Not within the set flow fluctuation tolerance range The current liquid pump height adjustment When the liquid pump height is adjusted according to the following formula: :

[0158] ;

[0159] in, Indicates the set initial height of the liquid pump.

[0160] By adjusting the height of the liquid pump, the magnetorheological fluid flow rate can be precisely adjusted within a small range, so that the magnetorheological fluid flow fluctuation at each polishing point meets the requirements of high-precision polishing, ensuring the constancy of the removal function during the polishing process.

[0161] Compared with the current mainstream real-time control scheme of flow change of magnetorheological fluid supply system based on follow-up device, the present invention uses electromagnetic flowmeter to measure the flow change of polishing system during polishing process and realizes coarse and fine two-stage adjustment of flow fluctuation by controlling the speed of liquid pump and the height of liquid pump, thereby realizing real-time control of removal function change. The present invention does not require additional follow-up device, has lower equipment cost, small flow change, and more stable magnetorheological fluid flow fluctuation.

[0162] In a fourth aspect, this embodiment further provides a magnetorheological polishing method based on nozzle position adjustment, which is implemented using the above-mentioned magnetorheological polishing system based on electromagnetic flowmeter sensing, and includes the following steps:

[0163] S1: Set the theoretical initial value of the liquid pump speed and the corresponding magnetorheological fluid flow rate at each polishing point of the test polishing element, polish the test polishing element, change the vertical distance between the liquid pump and the nozzle, and measure the magnetorheological fluid flow rate corresponding to different vertical distances using an electromagnetic flowmeter. If the magnetorheological fluid flow rate is different from the set theoretical initial value, adjust the liquid pump speed so that the magnetorheological fluid flow rate is the same as the set theoretical initial value, obtain discrete data of the vertical distance and the liquid pump speed, and obtain the first conversion relationship between the vertical distance and the liquid pump speed through data fitting; wherein, the first conversion relationship is expressed as , Indicates the liquid pump speed, Indicates the vertical distance, Indicates the conversion relationship between vertical distance and liquid pump speed;

[0164] And at each vertical distance, a different polishing gap is set, a different nozzle position is set at each polishing gap, and the magnetorheological fluid flow rate corresponding to the different nozzle positions at each polishing gap is measured by an electromagnetic flowmeter to obtain discrete data of the nozzle position and the magnetorheological fluid flow rate at each polishing gap. The fourth conversion relationship between the nozzle position at each polishing gap and the corresponding magnetorheological fluid flow rate is obtained by data fitting. The fourth conversion relationship can be expressed as ,in, Indicates the nozzle position under each polishing gap, Indicates the magnetorheological fluid flow rate corresponding to the nozzle position under each polishing gap, It shows the conversion relationship between the nozzle position and the magnetorheological fluid flow rate at each polishing gap.

[0165] Under different polishing gaps and vertical distances, the removal function is kept constant by changing the nozzle position, and then various data are collected to obtain the fourth conversion relationship between the nozzle at different positions and the corresponding magnetorheological fluid flow rate under each complete polishing gap, which is convenient for subsequent parameter adjustment.

[0166] Different polishing gaps mean that the relative distance between the polishing wheel and the magnet remains unchanged, while the distance between the entire magnetorheological polishing module and the test polishing element changes.

[0167] The purpose of step S1 is to use the electromagnetic flowmeter to establish a first conversion relationship between the vertical distance and the liquid pump speed and a fourth conversion relationship between the nozzle position in each polishing gap and the corresponding magnetorheological fluid flow rate, as follows:

[0168] The theoretical initial value of the liquid pump speed and the theoretical initial value of the corresponding magnetorheological fluid flow rate are set for each polishing point of the test polishing element, the vertical distance between the liquid pump and the nozzle is set to at least 10 different values, and the magnetorheological fluid flow rate corresponding to different vertical distances is measured using an electromagnetic flowmeter. If the magnetorheological fluid flow rate is different from the set theoretical initial value, the liquid pump speed is adjusted so that the magnetorheological fluid flow rate is the same as the set theoretical initial value, and discrete data of the vertical distance and the liquid pump speed are obtained. The data are then fitted using Matlab's Polyfit command (a basic general command of Matlab software) to obtain a first transformation relationship;

[0169] In each polishing gap, the nozzle position is set to at least 10 sets of different values. The nozzle position and the corresponding magnetorheological fluid flow rate in different polishing gaps are measured by an electromagnetic flowmeter to obtain discrete data of the nozzle position and the corresponding magnetorheological fluid flow rate in each polishing gap. The Polyfit command of Matlab (this command is a basic general command of Matlab software) is used to fit the data to obtain the fourth transformation relationship.

[0170] S2: According to the height change of the curved surface of the component to be polished, the liquid pump speed change is calculated based on the first conversion relationship to obtain the theoretical liquid pump speed corresponding to each polishing point of the component to be polished. The component to be polished is polished according to the theoretical liquid pump speed of each polishing point. At the same time, the actual magnetorheological fluid flow rate at the nozzle outlet corresponding to each polishing point is monitored in real time by an electromagnetic flowmeter and sent to the computer; wherein the theoretical liquid pump speed is expressed as ,in, Indicates the theoretical liquid pump speed of each polishing point, i=1, 2, 3...m, m represents the number of polishing points, Represents the vertical distance of the i-th polishing point.

[0171] The height change of the curved surface of the element to be polished reflects the change in the vertical distance between the liquid pump and the nozzle. According to the height of each polishing point on the curved surface of the element to be polished, the theoretical liquid pump speed of each polishing point is calculated using the first conversion relationship. The liquid pump speed is adjusted in real time according to the theoretical liquid pump speed of each polishing point to complete the coarse adjustment of the magnetorheological fluid flow change of the entire curved surface with a large range of high and low movements when the polishing system is polishing the element to be polished.

[0172] Since the magnetorheological fluid measured by the electromagnetic flowmeter needs to be transported through the pipeline and driven by the polishing wheel to reach the working area of ​​the polishing wheel, the magnetorheological fluid at the current flow rate needs to wait for a period of time to reach the working area of ​​the polishing wheel. In order to ensure the adjustment of the removal function change at each polishing point, it is necessary to set the residence time of the polishing point. The specific setting method is as follows:

[0173] S210: Establishing a measurement coordinate system of the laser tracker so that the measurement coordinate system is parallel to the tool coordinate system of the industrial robot.

[0174] S220: Drive the industrial robot to move toward the experimental table so that the lowest point of the polishing wheel just contacts the experimental table, place the target ball of the laser tracker at the nozzle outlet and measure the Z-axis coordinate Z4 of the target ball at this time.

[0175] S230: Place the target ball on the polishing platform close to the lowest point of the polishing wheel and measure the Z-axis coordinate of the target ball at this time , then the vertical distance between the nozzle and the lowest point of the polishing wheel is The time required for the magnetorheological fluid sprayed from the magnetorheological supply system to reach the lowest point of the polishing wheel is ,in, Indicates the number of revolutions per second of the polishing wheel. Indicates the length of the pipe between the electromagnetic flowmeter and the nozzle. represents the magnetorheological fluid flow rate, Indicates the radius of the polishing wheel.

[0176] When the computer generates the polishing control program, if the dwell time of each polishing point is If the dwell time of a polishing point exists, the generated polishing control program is appropriate. , then extend the dwell time of the polishing point , regenerate the polishing control program so that the dwell time of each polishing point .

[0177] S3: Set the flow fluctuation tolerance range in the computer, and determine whether the actual magnetorheological fluid flow at the nozzle outlet corresponding to each polishing point exceeds the set flow fluctuation tolerance range. If it does not exceed, keep the liquid pump height of the polishing point unchanged. If it exceeds, control the nozzle adjustment motor to adjust the nozzle position of the polishing point until the actual magnetorheological fluid flow does not exceed the flow fluctuation tolerance range, so as to maintain the removal function of each polishing point constant.

[0178] Since optical component polishing is a variable-speed motion of the polishing system, the movement speed between two adjacent polishing points is often different. In the process from one polishing point to the next, there is often a mismatch between the theoretical polishing position and the actual polishing position, the magnetorheological fluid flow fluctuates, and the removal function changes.

[0179] Therefore, it is necessary to set the tolerance range of the magnetorheological fluid flow fluctuation during the polishing process in the computer. , is the lower limit of the magnetorheological fluid flow fluctuation, is the upper limit of magnetorheological fluid flow fluctuation.

[0180] During the polishing process, the actual magnetorheological fluid flow rate at the nozzle outlet corresponding to each polishing point is measured in real time by an electromagnetic flowmeter. If the measured actual magnetorheological fluid flow rate is If the actual magnetorheological fluid flow rate is not within the range, the magnetorheological fluid flow fluctuation meets the requirements of high-precision polishing, and the measurement data does not need to be output. If the flow rate of the magnetorheological fluid is within the specified range, the fluctuation of the magnetorheological fluid flow rate does not meet the requirements of high-precision polishing. The measurement data needs to be output to the computer for processing, and the computer-processed data is sent to the nozzle adjustment motor. Finally, the magnetorheological fluid flow rate change is regulated by adjusting the nozzle position to maintain the removal function constant.

[0181] In order to ensure the safety of polishing, the maximum adjustment amount of the nozzle position needs to be set in the computer. , place the component to be polished on the polishing platform and fix it, drive the polishing system to polish the component to be polished, and use the electromagnetic flowmeter to measure the actual magnetorheological fluid flow at the nozzle outlet .

[0182] If the actual magnetorheological fluid flow rate at the nozzle outlet corresponding to the current polishing point Within the set flow fluctuation tolerance range Keep the nozzle position of the polishing point unchanged;

[0183] If the actual magnetorheological fluid flow rate at the nozzle outlet corresponding to the current polishing point Not within the set flow fluctuation tolerance range The current nozzle position adjustment amount When , adjust the current nozzle position according to the following formula :

[0184] ;

[0185] If the actual magnetorheological fluid flow rate at the nozzle outlet corresponding to the current polishing point Not within the set flow fluctuation tolerance range The current nozzle position adjustment amount When , adjust the current nozzle position according to the following formula :

[0186] ;

[0187] in, Indicates the set initial nozzle position.

[0188] By adjusting the nozzle position, the magnetorheological fluid flow rate can be precisely adjusted within a small range, so that the magnetorheological fluid flow fluctuation at each polishing point meets the requirements of high-precision polishing, ensuring the constancy of the removal function during the polishing process.

[0189] Compared with the current mainstream real-time control scheme of flow change of magnetorheological fluid supply system based on follow-up device, the present invention uses electromagnetic flowmeter to measure the flow change of polishing system during polishing process and realizes coarse and fine adjustment of flow fluctuation by controlling the speed of liquid pump and the position of nozzle, thereby realizing real-time control of removal function change. The present invention does not require additional follow-up device, has lower equipment cost, small flow change, and more stable magnetorheological fluid flow fluctuation.

[0190] In a fifth aspect, this embodiment further provides a magnetorheological polishing method based on polishing wheel speed regulation, which is implemented using the above-mentioned magnetorheological polishing system based on electromagnetic flowmeter sensing, and includes the following steps:

[0191] S1: Set the theoretical initial value of the liquid pump speed and the corresponding magnetorheological fluid flow rate at each polishing point of the test polishing element, polish the test polishing element, change the vertical distance between the liquid pump and the nozzle, and measure the magnetorheological fluid flow rate corresponding to different vertical distances using an electromagnetic flowmeter. If the magnetorheological fluid flow rate is different from the set theoretical initial value, adjust the liquid pump speed so that the magnetorheological fluid flow rate is the same as the set theoretical initial value, obtain discrete data of the vertical distance and the liquid pump speed, and obtain the first conversion relationship between the vertical distance and the liquid pump speed through data fitting; wherein, the first conversion relationship is expressed as , Indicates the liquid pump speed, Indicates the vertical distance, Indicates the conversion relationship between vertical distance and liquid pump speed;

[0192] And at each vertical distance, a different polishing gap is set, a different polishing wheel speed is set at each polishing gap, and the magnetorheological fluid flow corresponding to the different polishing wheel speeds at each polishing gap is measured by an electromagnetic flowmeter to obtain discrete data of the polishing wheel speed and the magnetorheological fluid flow at each polishing gap. The fifth conversion relationship between the nozzle position at each polishing gap and the corresponding magnetorheological fluid flow is obtained by data fitting. The fifth conversion relationship can be expressed as ,in, Indicates the polishing wheel speed at each polishing gap, Indicates the magnetorheological fluid flow rate corresponding to the polishing wheel speed at each polishing gap, It represents the conversion relationship between the polishing wheel speed and the magnetorheological fluid flow rate at each polishing gap.

[0193] At different polishing gaps and vertical distances, the removal function is kept constant by changing the polishing wheel speed, and then various data are collected to obtain the fifth conversion relationship between the polishing wheel at different speeds and the corresponding magnetorheological fluid flow rate at each polishing gap, which facilitates subsequent parameter adjustment.

[0194] Different polishing gaps mean that the relative distance between the polishing wheel and the magnet remains unchanged, while the distance between the entire magnetorheological polishing module and the test polishing element changes.

[0195] The purpose of step S1 is to use the electromagnetic flowmeter to establish a first conversion relationship between the vertical distance and the liquid pump speed and a fifth conversion relationship between the polishing wheel speed and the corresponding magnetorheological fluid flow rate at each polishing gap, as follows:

[0196] The theoretical initial value of the liquid pump speed and the theoretical initial value of the corresponding magnetorheological fluid flow rate are set for each polishing point of the test polishing element, the vertical distance between the liquid pump and the nozzle is set to at least 10 different values, and the magnetorheological fluid flow rate corresponding to different vertical distances is measured using an electromagnetic flowmeter. If the magnetorheological fluid flow rate is different from the set theoretical initial value, the liquid pump speed is adjusted so that the magnetorheological fluid flow rate is the same as the set theoretical initial value, and discrete data of the vertical distance and the liquid pump speed are obtained. The data are then fitted using Matlab's Polyfit command (a basic general command of Matlab software) to obtain a first transformation relationship;

[0197] At each polishing gap, the polishing wheel speed is set to at least 10 different values. The polishing wheel speed and the corresponding magnetorheological fluid flow rate at different polishing gaps are measured by an electromagnetic flowmeter, and discrete data of the polishing wheel speed and the corresponding magnetorheological fluid flow rate at each polishing gap are obtained. The Polyfit command of Matlab (this command is a basic general command of Matlab software) is used to fit the data to obtain the fifth transformation relationship.

[0198] S2: According to the height change of the curved surface of the component to be polished, the liquid pump speed change is calculated based on the first conversion relationship to obtain the theoretical liquid pump speed corresponding to each polishing point of the component to be polished. The component to be polished is polished according to the theoretical liquid pump speed of each polishing point. At the same time, the actual magnetorheological fluid flow rate at the nozzle outlet corresponding to each polishing point is monitored in real time by an electromagnetic flowmeter and sent to the computer; wherein the theoretical liquid pump speed is expressed as ,in, Indicates the theoretical liquid pump speed of each polishing point, i=1, 2, 3...m, m represents the number of polishing points, Represents the vertical distance of the i-th polishing point.

[0199] The height change of the curved surface of the element to be polished reflects the change in the vertical distance between the liquid pump and the nozzle. According to the height of each polishing point on the curved surface of the element to be polished, the theoretical liquid pump speed of each polishing point is calculated using the first conversion relationship. The liquid pump speed is adjusted in real time according to the theoretical liquid pump speed of each polishing point to complete the coarse adjustment of the magnetorheological fluid flow change of the entire curved surface with a large range of high and low movements when the polishing system is polishing the element to be polished.

[0200] Since the magnetorheological fluid measured by the electromagnetic flowmeter needs to be transported through the pipeline and driven by the polishing wheel to reach the working area of ​​the polishing wheel, the magnetorheological fluid at the current flow rate needs to wait for a period of time to reach the working area of ​​the polishing wheel. In order to ensure the adjustment of the removal function change at each polishing point, it is necessary to set the residence time of the polishing point. The specific setting method is as follows:

[0201] S210: Establishing a measurement coordinate system of the laser tracker so that the measurement coordinate system is parallel to the tool coordinate system of the industrial robot.

[0202] S220: Drive the industrial robot to move toward the experimental table so that the lowest point of the polishing wheel just contacts the experimental table, place the target ball of the laser tracker at the nozzle outlet and measure the Z-axis coordinate Z4 of the target ball at this time.

[0203] S230: Place the target ball on the polishing platform close to the lowest point of the polishing wheel and measure the Z-axis coordinate of the target ball at this time , then the vertical distance between the nozzle and the lowest point of the polishing wheel is The time required for the magnetorheological fluid sprayed from the magnetorheological supply system to reach the lowest point of the polishing wheel is ,in, Indicates the number of revolutions per second of the polishing wheel. Indicates the length of the pipe between the electromagnetic flowmeter and the nozzle. represents the magnetorheological fluid flow rate, Indicates the radius of the polishing wheel.

[0204] When the computer generates the polishing control program, if the dwell time of each polishing point is If the dwell time of a polishing point exists, the generated polishing control program is appropriate. , then extend the dwell time of the polishing point , regenerate the polishing control program so that the dwell time of each polishing point .

[0205] S3: Set the flow fluctuation tolerance range in the computer, and determine whether the actual magnetorheological fluid flow at the nozzle outlet corresponding to each polishing point exceeds the set flow fluctuation tolerance range. If it does not exceed, keep the polishing wheel speed of the polishing point unchanged. If it exceeds, control the drive motor to adjust the polishing wheel speed of the polishing point until the actual magnetorheological fluid flow does not exceed the flow fluctuation tolerance range, so as to maintain the removal function of each polishing point constant.

[0206] Since optical component polishing is a variable-speed motion of the polishing system, the movement speed between two adjacent polishing points is often different. In the process from one polishing point to the next, there is often a mismatch between the theoretical polishing position and the actual polishing position, the magnetorheological fluid flow fluctuates, and the removal function changes.

[0207] Therefore, it is necessary to set the tolerance range of the magnetorheological fluid flow fluctuation during the polishing process in the computer. , is the lower limit of the magnetorheological fluid flow fluctuation, is the upper limit of magnetorheological fluid flow fluctuation.

[0208] During the polishing process, the actual magnetorheological fluid flow rate at the nozzle outlet corresponding to each polishing point is measured in real time by an electromagnetic flowmeter. If the measured actual magnetorheological fluid flow rate is If the actual magnetorheological fluid flow rate is not within the range, the magnetorheological fluid flow fluctuation meets the requirements of high-precision polishing, and the measurement data does not need to be output. If the polishing wheel speed is within the specified range, the magnetorheological fluid flow fluctuation does not meet the requirements of high-precision polishing. The measurement data needs to be output to the computer for processing, and the computer-processed data is sent to the industrial robot. Finally, the magnetorheological fluid flow change is regulated by adjusting the polishing wheel speed to maintain the removal function constant.

[0209] In order to ensure the safety of polishing, the maximum adjustment of the polishing wheel speed needs to be set in the computer. , place the component to be polished on the polishing platform and fix it, drive the polishing system to polish the component to be polished, and use the electromagnetic flowmeter to measure the actual magnetorheological fluid flow at the nozzle outlet .

[0210] If the actual magnetorheological fluid flow rate at the nozzle outlet corresponding to the current polishing point Within the set flow fluctuation tolerance range Keep the polishing wheel speed of the current polishing point unchanged;

[0211] If the actual magnetorheological fluid flow rate at the nozzle outlet corresponding to the current polishing point Not within the set flow fluctuation tolerance range The current polishing wheel speed adjustment value When the current polishing wheel speed is adjusted according to the following formula :

[0212] ;

[0213] If the actual magnetorheological fluid flow rate at the nozzle outlet corresponding to the current polishing point Not within the set flow fluctuation tolerance range The current polishing wheel speed adjustment value When the current polishing wheel speed is adjusted according to the following formula :

[0214] ;

[0215] in, Indicates the initial rotation speed of the polishing wheel.

[0216] By adjusting the polishing wheel speed, the magnetorheological fluid flow rate can be precisely adjusted within a small range, so that the magnetorheological fluid flow fluctuation at each polishing point meets the requirements of high-precision polishing, ensuring the constancy of the removal function during the polishing process.

[0217] Compared with the current mainstream real-time control scheme of flow change of magnetorheological fluid supply system based on follow-up device, the present invention uses electromagnetic flowmeter to measure the flow change of polishing system during polishing process and realizes coarse and fine adjustment of flow fluctuation by controlling the speed of liquid pump and the speed of polishing wheel, thereby realizing real-time control of removal function change. The present invention does not require additional follow-up device, has lower equipment cost, small flow change, and more stable magnetorheological fluid flow fluctuation.

[0218] In a sixth aspect, this embodiment further provides a magnetorheological polishing method based on removal function regulation, which is implemented using the above-mentioned magnetorheological polishing system based on electromagnetic flowmeter sensing, and includes the following steps:

[0219] S1: Set the theoretical initial value of the magnetorheological fluid flow rate at each polishing point of the test polishing element, polish the test polishing element according to the theoretical initial value of the magnetorheological fluid flow rate, obtain the removal function, and simultaneously measure the theoretical magnetorheological fluid flow rate corresponding to each polishing point of the test polishing element by an electromagnetic flowmeter, and calculate the sixth conversion relationship between the removal function and the theoretical magnetorheological fluid flow rate, wherein the sixth conversion relationship is expressed as , Represents the removal function, Represents the theoretical magnetorheological fluid flow rate at each polishing point of the test polishing element, The sixth conversion relationship between the theoretical magnetorheological fluid flow rate and the removal function at each polishing point of the experimental polishing element is shown.

[0220] S2: Set a flow fluctuation tolerance range in the computer, perform the first polishing on the component to be polished according to the theoretical magnetorheological fluid flow rate, measure the actual magnetorheological fluid flow rate at the nozzle outlet corresponding to each polishing point of the component to be polished by an electromagnetic flowmeter, and determine whether it exceeds the set flow fluctuation tolerance range. If it exceeds, record the actual magnetorheological fluid flow rate of the polishing point, and after the first polishing of the component to be polished is completed, solve the removal function corresponding to the recorded actual magnetorheological fluid flow rate of each polishing point based on the sixth conversion relationship to obtain a variable removal function set.

[0221] S3: performing secondary polishing on the component to be polished according to the variable removal function set, and determining the polishing amount of each polishing point during the secondary polishing of the component to be polished by using the variable removal function set.

[0222] After the first processing of the polished component is completed, the variable removal function set is obtained , when performing secondary processing on the polished component, the function set is removed As processing parameters, a processing control program is generated to complete secondary processing.

[0223] Combined with a variable removal function set, the conductive component to be polished is processed twice to achieve the high-precision magnetorheological processing requirements. This process does not require additional follow-up devices, lowers equipment costs, minimizes flow rate changes, and stabilizes magnetorheological fluid flow fluctuations.

[0224] 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.

[0225] 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 polishing system based on electromagnetic flowmeter sensing, characterized in that: include: a polishing platform on which the element to be polished and the test polishing element are arranged; A polishing assembly includes an industrial robot and a magnetorheological polishing module. The industrial robot is used to drive the magnetorheological polishing module to move to the location of a test polishing element or the location of an element to be polished. The magnetorheological polishing module is used to polish the element to be polished or the test polishing element. The magnetorheological polishing module includes a magnetorheological mounting frame, a polishing wheel, a nozzle, a magnet, an actuator group and a supply device. One end of the actuator group is connected to the magnetorheological mounting frame, and the other end of the actuator group is connected to the tool end of the industrial robot. The polishing wheel and the magnet are respectively mounted on the magnetorheological mounting frame. The nozzle is mounted on the magnetorheological mounting frame through a nozzle adjustment seat. The nozzle adjustment seat is used to adjust the position of the nozzle. The nozzle is used to spray magnetorheological fluid onto the polishing wheel. The magnet is used to change the stiffness of the magnetorheological fluid. The polishing wheel is used to polish the test polishing element or the element to be polished. The supply device is arranged on one side of the polishing platform and is used to pump magnetorheological fluid into the nozzle. An electromagnetic flowmeter is installed on the industrial robot to monitor the flow rate of the magnetorheological fluid at the nozzle outlet; The laser tracker is set on one side of the polishing platform and is used in conjunction with the target ball to measure the vertical distance between the nozzle and the liquid pump; a computer configured to establish, based on the magnetorheological fluid flow rate monitored by the electromagnetic flowmeter, a first conversion relationship between the vertical distance and the liquid pump speed, a second conversion relationship between the polishing gap and the magnetorheological fluid flow rate, a third conversion relationship between the liquid pump height and the magnetorheological fluid flow rate, a fourth conversion relationship between the nozzle position and the magnetorheological fluid flow rate, and a fifth conversion relationship between the polishing wheel speed and the magnetorheological fluid flow rate, and to adjust the liquid pump speed, the actuator group output displacement, the liquid pump height, the nozzle position, and the polishing wheel speed based on the first to fifth conversion relationships to maintain a constant removal function for each polishing point on the component to be polished; The computer is used to establish a sixth conversion relationship between the removal function and the magnetorheological fluid flow rate according to the magnetorheological fluid flow monitored by the electromagnetic flowmeter, and obtain a variable removal function set according to the sixth conversion relationship to perform secondary polishing on the polishing component.

2. The magnetorheological polishing system based on electromagnetic flowmeter sensing according to claim 1 is characterized in that: The supply device includes a liquid pump, a mounting bracket, a mounting plate, a linear guide and a ball screw stepper motor; wherein, the linear guide and the ball screw stepper motor are respectively vertically mounted on the mounting bracket, and the linear guides are distributed on both sides of the ball screw stepper motor, the liquid pump is mounted on the mounting plate, and the mounting plate is respectively connected to the slider of the linear guide and the nut of the ball screw stepper motor.

3. The magnetorheological polishing system based on electromagnetic flowmeter sensing according to claim 1 is characterized in that: The nozzle is installed on the magnetorheological mounting frame through the nozzle adjustment seat, and the position of the nozzle relative to the polishing wheel is adjusted through the nozzle adjustment seat; the nozzle adjustment seat includes a fixing frame, a nozzle adjustment motor, a push plate, a nozzle mounting frame and an arc guide rail; wherein, the fixing frame is installed on the magnetorheological mounting frame, the nozzle adjustment motor and the arc guide rail are respectively installed on the fixing frame, the push plate is installed at the output end of the nozzle adjustment motor, the nozzle mounting frame is respectively connected to the push plate and the slider of the arc guide rail, and the nozzle is installed on the nozzle mounting frame.

4. The magnetorheological polishing system based on electromagnetic flowmeter sensing according to claim 1 is characterized in that: The magnetorheological polishing module further includes a polishing wheel drive device, which includes a driving motor, a motor connecting plate, a driving wheel, a driven wheel and a synchronous belt. The driving motor is installed on the connecting plate, a bearing seat is installed on the connecting plate, a bearing is installed in the bearing seat, the bearing is connected to the polishing wheel, the driven wheel is mounted on the bearing, the driving wheel is mounted on the output end of the driving motor, and the synchronous belt is tensioned on the driven wheel and the driving wheel.

5. A magnetorheological polishing method based on adjusting the polishing gap by an actuator, implemented by the magnetorheological polishing system based on electromagnetic flowmeter sensing according to claim 1, characterized in that: The steps include: S1: Set the theoretical initial value of the liquid pump speed and the corresponding magnetorheological fluid flow rate at each polishing point of the test polishing element, polish the test polishing element, change the vertical distance between the liquid pump and the nozzle, and measure the magnetorheological fluid flow rate corresponding to different vertical distances using an electromagnetic flowmeter. If the magnetorheological fluid flow rate is different from the set theoretical initial value, adjust the liquid pump speed so that the magnetorheological fluid flow rate is the same as the set theoretical initial value, obtain discrete data of the vertical distance and the liquid pump speed, and obtain the first conversion relationship between the vertical distance and the liquid pump speed through data fitting; wherein, the first conversion relationship is expressed as , Indicates the liquid pump speed, Indicates the vertical distance, Indicates the conversion relationship between vertical distance and liquid pump speed; And at each vertical distance, different polishing gaps are set, and the magnetorheological fluid flow corresponding to different polishing gaps at each vertical distance is measured by an electromagnetic flowmeter to obtain discrete data of the polishing gap and the magnetorheological fluid flow at each vertical distance. The second conversion relationship between the polishing gap and the corresponding magnetorheological fluid flow at each vertical distance is obtained by data fitting. The second conversion relationship can be expressed as ,in, Indicates the polishing gap at each vertical distance, Indicates the magnetorheological fluid flow rate corresponding to the polishing gap at each vertical distance, It shows the conversion relationship between the polishing gap and the magnetorheological fluid flow rate at various vertical distances; S2: According to the height change of the curved surface of the component to be polished, the liquid pump speed change is calculated based on the first conversion relationship to obtain the theoretical liquid pump speed corresponding to each polishing point of the component to be polished. The component to be polished is polished according to the theoretical liquid pump speed of each polishing point. At the same time, the actual magnetorheological fluid flow rate at the nozzle outlet corresponding to each polishing point is monitored in real time by an electromagnetic flowmeter and sent to the computer; wherein the theoretical liquid pump speed is expressed as ,in, Indicates the theoretical liquid pump speed of each polishing point, i=1, 2, 3...m, m represents the number of polishing points, represents the vertical distance of the i-th polishing point; S3: Set the flow fluctuation tolerance range in the computer to determine whether the actual magnetorheological fluid flow at the nozzle outlet corresponding to each polishing point exceeds the set flow fluctuation tolerance range. If it does not exceed, keep the polishing gap of the polishing point unchanged. If it exceeds, control the output displacement of the actuator group and then adjust the polishing gap until the actual magnetorheological fluid flow does not exceed the flow fluctuation tolerance range to maintain the removal function of each polishing point constant.

6. The magnetorheological polishing method based on adjusting the polishing gap by an actuator according to claim 5, characterized in that: When polishing each polishing point of the polishing element, the dwell time is set for each polishing point, which specifically includes the following steps: S210: Establishing a measurement coordinate system of the laser tracker so that the measurement coordinate system is parallel to the tool coordinate system of the industrial robot; S220: driving the industrial robot to move toward the polishing platform so that the lowest point of the polishing wheel just contacts the polishing platform, placing the target ball at the nozzle outlet, and measuring the Z-axis coordinate Z4 of the target ball at this time; S230: Place the target ball on the polishing platform close to the lowest point of the polishing wheel and measure the Z-axis coordinate of the target ball at this time , then the vertical distance between the nozzle and the lowest point of the polishing wheel is The time required for the magnetorheological fluid sprayed from the magnetorheological supply system to reach the lowest point of the polishing wheel is ,in, Indicates the number of revolutions per second of the polishing wheel. Indicates the length of the pipe between the electromagnetic flowmeter and the nozzle. represents the magnetorheological fluid flow rate, Indicates the radius of the polishing wheel.

7. The magnetorheological polishing method based on adjusting the polishing gap by an actuator according to claim 6, characterized in that: When the computer generates the polishing control program, if the dwell time of each polishing point is If the dwell time of a polishing point exists, the generated polishing control program is appropriate. , then extend the dwell time of the polishing point , regenerate the polishing control program so that the dwell time of each polishing point .

8. The magnetorheological polishing method based on adjusting the polishing gap by an actuator according to claim 5, characterized in that: In step S3, the maximum adjustment amount of the output displacement of the actuator group is set in the computer to ; as well as, If the actual magnetorheological fluid flow rate at the nozzle outlet corresponding to the current polishing point Within the set flow fluctuation tolerance range Keep the polishing gap of the polishing point unchanged; If the actual magnetorheological fluid flow rate at the nozzle outlet corresponding to the current polishing point Not within the set flow fluctuation tolerance range The adjustment amount of the output displacement of the current actuator group , then adjust the output displacement of the current actuator group according to the following formula : ； If the actual magnetorheological fluid flow rate at the nozzle outlet corresponding to the current polishing point Not within the set flow fluctuation tolerance range The adjustment amount of the output displacement of the current actuator group , then adjust the output displacement of the current actuator group according to the following formula : ； in, Represents the initial output displacement of the actuator group.

9. A magnetorheological polishing method based on liquid pump height adjustment, implemented using the magnetorheological polishing system based on electromagnetic flowmeter sensing according to claim 2, characterized in that: The steps include: S1: Set the theoretical initial value of the liquid pump speed and the corresponding magnetorheological fluid flow rate at each polishing point of the test polishing element, polish the test polishing element, change the vertical distance between the liquid pump and the nozzle, and measure the magnetorheological fluid flow rate corresponding to different vertical distances using an electromagnetic flowmeter. If the magnetorheological fluid flow rate is different from the set theoretical initial value, adjust the liquid pump speed so that the magnetorheological fluid flow rate is the same as the set theoretical initial value, obtain discrete data of the vertical distance and the liquid pump speed, and obtain the first conversion relationship between the vertical distance and the liquid pump speed through data fitting; wherein, the first conversion relationship is expressed as , Indicates the liquid pump speed, Indicates the vertical distance, Indicates the conversion relationship between vertical distance and liquid pump speed; And at each vertical distance, a different polishing gap is set, a different liquid pump height is set at each polishing gap, and the magnetorheological fluid flow rate corresponding to the different liquid pump heights at each polishing gap is measured by an electromagnetic flowmeter to obtain discrete data of the liquid pump height and the magnetorheological fluid flow rate at each polishing gap. The third conversion relationship between the liquid pump height at each polishing gap and the corresponding magnetorheological fluid flow rate is obtained by data fitting. The third conversion relationship can be expressed as: ,in, Indicates the liquid pump height under each polishing gap, Indicates the magnetorheological fluid flow rate corresponding to the liquid pump height under each polishing gap, It shows the conversion relationship between the liquid pump height and the magnetorheological fluid flow rate at each polishing gap; S2: According to the height change of the curved surface of the component to be polished, the liquid pump speed change is calculated based on the first conversion relationship to obtain the theoretical liquid pump speed corresponding to each polishing point of the component to be polished. The component to be polished is polished according to the theoretical liquid pump speed of each polishing point. At the same time, the actual magnetorheological fluid flow rate at the nozzle outlet corresponding to each polishing point is monitored in real time by an electromagnetic flowmeter and sent to the computer; wherein the theoretical liquid pump speed is expressed as ,in, Indicates the theoretical liquid pump speed of each polishing point, i=1, 2, 3...m, m represents the number of polishing points, represents the vertical distance of the i-th polishing point; S3: Set the flow fluctuation tolerance range in the computer, and determine whether the actual magnetorheological fluid flow at the nozzle outlet corresponding to each polishing point exceeds the set flow fluctuation tolerance range. If it does not exceed, keep the liquid pump height of the polishing point unchanged. If it exceeds, control the ball screw stepper motor to adjust the liquid pump height of the polishing point until the actual magnetorheological fluid flow does not exceed the flow fluctuation tolerance range, so as to maintain the removal function of each polishing point constant.

10. The magnetorheological polishing method based on liquid pump height adjustment according to claim 9, characterized in that: When polishing each polishing point of the polishing element, the dwell time is set for each polishing point, which specifically includes the following steps: S210: Establishing a measurement coordinate system of the laser tracker so that the measurement coordinate system is parallel to the tool coordinate system of the industrial robot; S220: driving the industrial robot to move toward the polishing platform so that the lowest point of the polishing wheel just contacts the polishing platform, placing the target ball at the nozzle outlet, and measuring the Z-axis coordinate Z4 of the target ball at this time; S230: Place the target ball on the polishing platform close to the lowest point of the polishing wheel and measure the Z-axis coordinate of the target ball at this time , then the vertical distance between the nozzle and the lowest point of the polishing wheel is The time required for the magnetorheological fluid sprayed from the magnetorheological supply system to reach the lowest point of the polishing wheel is ,in, Indicates the number of revolutions per second of the polishing wheel. Indicates the length of the pipe between the electromagnetic flowmeter and the nozzle. represents the magnetorheological fluid flow rate, Indicates the radius of the polishing wheel.

11. The magnetorheological polishing method based on liquid pump height adjustment according to claim 10, characterized in that: When the computer generates the polishing control program, if the dwell time of each polishing point is If the dwell time of a polishing point exists, the generated polishing control program is appropriate. , then extend the dwell time of the polishing point , regenerate the polishing control program so that the dwell time of each polishing point .

12. The magnetorheological polishing method based on liquid pump height adjustment according to claim 9, characterized in that: In step S3, the maximum adjustment amount of the liquid pump height is set in the computer to ; as well as, If the actual magnetorheological fluid flow rate at the nozzle outlet corresponding to the current polishing point Within the set flow fluctuation tolerance range Inside, keep the liquid pump height of the polishing point unchanged; If the actual magnetorheological fluid flow rate at the nozzle outlet corresponding to the current polishing point Not within the set flow fluctuation tolerance range The current liquid pump height adjustment When the liquid pump height is adjusted according to the following formula: : ； If the actual magnetorheological fluid flow rate at the nozzle outlet corresponding to the current polishing point Not within the set flow fluctuation tolerance range The current liquid pump height adjustment When the liquid pump height is adjusted according to the following formula: : ； in, Indicates the initial height of the liquid pump.

13. A magnetorheological polishing method based on nozzle position adjustment, implemented using the magnetorheological polishing system based on electromagnetic flowmeter sensing according to claim 3, characterized in that: The steps include: S1: Set the theoretical initial value of the liquid pump speed and the corresponding magnetorheological fluid flow rate at each polishing point of the test polishing element, polish the test polishing element, change the vertical distance between the liquid pump and the nozzle, and measure the magnetorheological fluid flow rate corresponding to different vertical distances using an electromagnetic flowmeter. If the magnetorheological fluid flow rate is different from the set theoretical initial value, adjust the liquid pump speed so that the magnetorheological fluid flow rate is the same as the set theoretical initial value, obtain discrete data of the vertical distance and the liquid pump speed, and obtain the first conversion relationship between the vertical distance and the liquid pump speed through data fitting; wherein, the first conversion relationship is expressed as , Indicates the liquid pump speed, Indicates the vertical distance, Indicates the conversion relationship between vertical distance and liquid pump speed; And at each vertical distance, a different polishing gap is set, a different nozzle position is set at each polishing gap, and the magnetorheological fluid flow rate corresponding to the different nozzle positions at each polishing gap is measured by an electromagnetic flowmeter to obtain discrete data of the nozzle position and the magnetorheological fluid flow rate at each polishing gap. The fourth conversion relationship between the nozzle position at each polishing gap and the corresponding magnetorheological fluid flow rate is obtained by data fitting. The fourth conversion relationship can be expressed as ,in, Indicates the nozzle position under each polishing gap, Indicates the magnetorheological fluid flow rate corresponding to the nozzle position under each polishing gap, It shows the conversion relationship between the nozzle position and the magnetorheological fluid flow rate at each polishing gap; S2: According to the height change of the curved surface of the component to be polished, the liquid pump speed change is calculated based on the first conversion relationship to obtain the theoretical liquid pump speed corresponding to each polishing point of the component to be polished. The component to be polished is polished according to the theoretical liquid pump speed of each polishing point. At the same time, the actual magnetorheological fluid flow rate at the nozzle outlet corresponding to each polishing point is monitored in real time by an electromagnetic flowmeter and sent to the computer; wherein the theoretical liquid pump speed is expressed as ,in, Indicates the theoretical liquid pump speed of each polishing point, i=1, 2, 3...m, m represents the number of polishing points, represents the vertical distance of the i-th polishing point; S3: Set the flow fluctuation tolerance range in the computer, and determine whether the actual magnetorheological fluid flow at the nozzle outlet corresponding to each polishing point exceeds the set flow fluctuation tolerance range. If it does not exceed, keep the nozzle position of the polishing point unchanged. If it exceeds, control the nozzle adjustment motor to adjust the nozzle position of the polishing point until the actual magnetorheological fluid flow does not exceed the flow fluctuation tolerance range, so as to maintain the removal function of each polishing point constant.

14. The magnetorheological polishing method based on nozzle position adjustment according to claim 13, characterized in that: When polishing each polishing point of the polishing element, the dwell time is set for each polishing point, which specifically includes the following steps: S210: Establishing a measurement coordinate system of the laser tracker so that the measurement coordinate system is parallel to the tool coordinate system of the industrial robot; S220: driving the industrial robot to move toward the polishing platform so that the lowest point of the polishing wheel just contacts the polishing platform, placing the target ball at the nozzle outlet, and measuring the Z-axis coordinate Z4 of the target ball at this time; S230: Place the target ball on the polishing platform close to the lowest point of the polishing wheel and measure the Z-axis coordinate of the target ball at this time , then the vertical distance between the nozzle and the lowest point of the polishing wheel is The time required for the magnetorheological fluid sprayed from the magnetorheological supply system to reach the lowest point of the polishing wheel is ,in, Indicates the number of revolutions per second of the polishing wheel. Indicates the length of the pipe between the electromagnetic flowmeter and the nozzle. represents the magnetorheological fluid flow rate, Indicates the radius of the polishing wheel.

15. The magnetorheological polishing method based on nozzle position adjustment according to claim 14, characterized in that: When the computer generates the polishing control program, if the dwell time of each polishing point is If the dwell time of a polishing point exists, the generated polishing control program is appropriate. , then extend the dwell time of the polishing point , regenerate the polishing control program so that the dwell time of each polishing point .

16. The magnetorheological polishing method based on nozzle position adjustment according to claim 13, characterized in that: In step S3, the maximum adjustment amount of the nozzle position is set in the computer as ; as well as, If the actual magnetorheological fluid flow rate at the nozzle outlet corresponding to the current polishing point Within the set flow fluctuation tolerance range Keep the nozzle position of the polishing point unchanged; If the actual magnetorheological fluid flow rate at the nozzle outlet corresponding to the current polishing point Not within the set flow fluctuation tolerance range The current nozzle position adjustment amount When , adjust the current nozzle position according to the following formula : ； If the actual magnetorheological fluid flow rate at the nozzle outlet corresponding to the current polishing point Not within the set flow fluctuation tolerance range The current nozzle position adjustment amount When , adjust the current nozzle position according to the following formula : ； in, Indicates the initial position of the nozzle.

17. A magnetorheological polishing method based on polishing wheel speed regulation, implemented using the magnetorheological polishing system based on electromagnetic flowmeter sensing according to claim 4, characterized in that: The steps include: S1: Set the theoretical initial value of the liquid pump speed and the corresponding magnetorheological fluid flow rate at each polishing point of the test polishing element, polish the test polishing element, change the vertical distance between the liquid pump and the nozzle, and measure the magnetorheological fluid flow rate corresponding to different vertical distances using an electromagnetic flowmeter. If the magnetorheological fluid flow rate is different from the set theoretical initial value, adjust the liquid pump speed so that the magnetorheological fluid flow rate is the same as the set theoretical initial value, obtain discrete data of the vertical distance and the liquid pump speed, and obtain the first conversion relationship between the vertical distance and the liquid pump speed through data fitting; wherein, the first conversion relationship is expressed as , Indicates the liquid pump speed, Indicates the vertical distance, Indicates the conversion relationship between vertical distance and liquid pump speed; And at each vertical distance, a different polishing gap is set, a different polishing wheel speed is set at each polishing gap, and the magnetorheological fluid flow corresponding to the different polishing wheel speeds at each polishing gap is measured by an electromagnetic flowmeter to obtain discrete data of the polishing wheel speed and the magnetorheological fluid flow at each polishing gap. The fifth conversion relationship between the nozzle position at each polishing gap and the corresponding magnetorheological fluid flow is obtained by data fitting. The fifth conversion relationship can be expressed as ,in, Indicates the polishing wheel speed at each polishing gap, Indicates the magnetorheological fluid flow rate corresponding to the polishing wheel speed at each polishing gap, It represents the conversion relationship between the polishing wheel speed and the magnetorheological fluid flow rate at each polishing gap; S2: According to the height change of the curved surface of the component to be polished, the liquid pump speed change is calculated based on the first conversion relationship to obtain the theoretical liquid pump speed corresponding to each polishing point of the component to be polished. The component to be polished is polished according to the theoretical liquid pump speed of each polishing point. At the same time, the actual magnetorheological fluid flow rate at the nozzle outlet corresponding to each polishing point is monitored in real time by an electromagnetic flowmeter and sent to the computer; wherein the theoretical liquid pump speed is expressed as ,in, Indicates the theoretical liquid pump speed of each polishing point, i=1, 2, 3...m, m represents the number of polishing points, represents the vertical distance of the i-th polishing point; S3: Set the flow fluctuation tolerance range in the computer, and determine whether the actual magnetorheological fluid flow at the nozzle outlet corresponding to each polishing point exceeds the set flow fluctuation tolerance range. If it does not exceed, keep the polishing wheel speed of the polishing point unchanged. If it exceeds, control the drive motor to adjust the polishing wheel speed of the polishing point until the actual magnetorheological fluid flow does not exceed the flow fluctuation tolerance range, so as to maintain the removal function of each polishing point constant.

18. The magnetorheological polishing method based on polishing wheel speed regulation according to claim 17, characterized in that: When polishing each polishing point of the polishing element, the dwell time is set for each polishing point, which specifically includes the following steps: S210: Establishing a measurement coordinate system of the laser tracker so that the measurement coordinate system is parallel to the tool coordinate system of the industrial robot; S220: driving the industrial robot to move toward the polishing platform so that the lowest point of the polishing wheel just contacts the polishing platform, placing the target ball at the nozzle outlet, and measuring the Z-axis coordinate Z4 of the target ball at this time; S230: Place the target ball on the polishing platform close to the lowest point of the polishing wheel and measure the Z-axis coordinate of the target ball at this time , then the vertical distance between the nozzle and the lowest point of the polishing wheel is The time required for the magnetorheological fluid sprayed from the magnetorheological supply system to reach the lowest point of the polishing wheel is ,in, Indicates the number of revolutions per second of the polishing wheel. Indicates the length of the pipe between the electromagnetic flowmeter and the nozzle. represents the magnetorheological fluid flow rate, Indicates the radius of the polishing wheel.

19. The magnetorheological polishing method based on polishing wheel speed regulation according to claim 18, characterized in that: When the computer generates the polishing control program, if the dwell time of each polishing point is If the dwell time of a polishing point exists, the generated polishing control program is appropriate. , then extend the dwell time of the polishing point , regenerate the polishing control program so that the dwell time of each polishing point .

20. The magnetorheological polishing method based on polishing wheel speed regulation according to claim 17, characterized in that: In step S3, the maximum adjustment amount of the polishing wheel speed is set in the computer to ; as well as, If the actual magnetorheological fluid flow rate at the nozzle outlet corresponding to the current polishing point Within the set flow fluctuation tolerance range Keep the polishing wheel speed of the current polishing point unchanged; If the actual magnetorheological fluid flow rate at the nozzle outlet corresponding to the current polishing point Not within the set flow fluctuation tolerance range The current polishing wheel speed adjustment value When the current polishing wheel speed is adjusted according to the following formula : ； If the actual magnetorheological fluid flow rate at the nozzle outlet corresponding to the current polishing point Not within the set flow fluctuation tolerance range The current polishing wheel speed adjustment value When the current polishing wheel speed is adjusted according to the following formula : ； in, Indicates the initial rotation speed of the polishing wheel.

21. A magnetorheological polishing method based on removal function regulation, implemented using the magnetorheological polishing system based on electromagnetic flowmeter sensing according to claim 1, characterized in that: The steps include: S1: Set the theoretical initial value of the magnetorheological fluid flow rate at each polishing point of the test polishing element, polish the test polishing element according to the theoretical initial value of the magnetorheological fluid flow rate, obtain the removal function, and simultaneously measure the theoretical magnetorheological fluid flow rate corresponding to each polishing point of the test polishing element by an electromagnetic flowmeter, and calculate the sixth conversion relationship between the removal function and the theoretical magnetorheological fluid flow rate, wherein the sixth conversion relationship is expressed as , Represents the removal function, Represents the theoretical magnetorheological fluid flow rate at each polishing point of the test polishing element, The sixth conversion relationship between the theoretical magnetorheological fluid flow rate and the removal function at each polishing point of the test polishing element is represented; S2: setting a flow fluctuation tolerance range in a computer, performing a first polish on the component to be polished based on the theoretical magnetorheological fluid flow rate, measuring the actual magnetorheological fluid flow rate at the nozzle outlet corresponding to each polishing point of the component to be polished using an electromagnetic flowmeter, and determining whether it exceeds the set flow fluctuation tolerance range. If so, recording the actual magnetorheological fluid flow rate at the polishing point, and after the first polishing of the component to be polished is completed, solving the removal function corresponding to the recorded actual magnetorheological fluid flow rate at each polishing point based on the sixth transformation relationship to obtain a variable removal function set; S3: performing secondary polishing on the component to be polished according to the variable removal function set, and determining the polishing amount of each polishing point during the secondary polishing of the component to be polished by using the variable removal function set.

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