Milling Magnetorheological Absorption Vibration System and Control Method for Thin-Walled Parts Considering Temperature Rise Effect

Abstract

The present invention relates to the field of high-precision machining technology, and provides a milling magnetorheological vibration absorption system and control method for thin-walled parts considering the temperature rise effect. The system includes a magnetorheological vibration absorber assembly, an air-cooling assembly, and a control assembly. The control assembly includes a signal acquisition module and a driving module, which are respectively connected to the magnetorheological vibration absorber assembly and the air-cooling assembly. It can collect the workpiece vibration displacement signal and the magnetorheological elastomer temperature signal, perform analysis and processing, and issue corresponding control signals according to the vibration control algorithm and the temperature control algorithm, respectively adjusting the current magnitude of the excitation coil in the magnetorheological vibration absorber assembly and the on / off of the air pump in the air-cooling assembly. By adjusting the excitation current, the present invention can change the stiffness of the magnetorheological elastomer, so that the magnetorheological vibration absorption device can be applied to the problem of suppressing thin-walled part milling chatter. By forcibly air-cooling the magnetorheological elastomer, the magnetorheological vibration absorption device can work stably for a long time.

Description

Technical Field

[0001] The present invention relates to the technical field of high-precision machining, and particularly relates to a milling magnetorheological vibration absorption system and control method for thin-walled parts considering the temperature rise effect, which is applicable to the vibration reduction scenarios of milling machining of various thin-walled workpieces. Background Art

[0002] In recent years, thin-walled parts have been widely used in the fields of aviation, aerospace, etc. due to their advantages such as light weight and high specific strength, such as aero-engine blades, integral blisks, impellers, integral panels, etc. Usually, these workpieces have high precision requirements, many varieties and specifications, but small batch sizes, so most of them are manufactured by milling. However, their relative stiffness is low, the machining processability is poor, and chatter is extremely likely to occur when the milling cutter removes materials, resulting in a decline in the machining quality of the workpiece, and at the same time, it will also exacerbate the tool wear, seriously restricting the development of productivity.

[0003] As a typical semi-active vibration control device, the magnetorheological vibration absorber has the advantages of simple structure, low energy consumption, continuous and reversible operation, etc., and can well meet the needs of various vibration control occasions.

[0004] Patent document CN 110145564 A discloses a controllable flexible vibration reduction device for cutting thin-walled parts, which can adjust the magnitude of the current in the excitation coil according to the machining conditions to realize the continuous adjustment of the damping force. However, it does not consider the influence of the temperature rise effect on the frequency shift performance of the magnetorheological elastomer vibration absorber, and it is difficult to ensure long-term stable and effective operation.

[0005] In summary, the existing research on magnetorheological vibration absorption devices mainly has the following problems:

[0006] There is less consideration of the problem that the temperature rise effect generated by the long-term operation of the excitation coil makes the controllable frequency band of the magnetorheological vibration absorber narrower. This affects the working stability of the magnetorheological vibration absorption device and seriously restricts the application range of the magnetorheological vibration absorber.

[0007] Therefore, the present invention provides a milling magnetorheological vibration absorption system and method for thin-walled parts considering the temperature rise effect to solve the above technical problems. Summary of the Invention

[0008] The technical problems to be solved by the present invention:

[0009] Aiming at the deficiencies mentioned in the background art, the purpose of the present invention is to provide a milling magnetorheological vibration absorption system for thin-walled parts considering the temperature rise effect. By sensing the change of the milling vibration signal to adjust the excitation current and changing the stiffness of the magnetorheological elastomer, the magnetorheological vibration absorption device can be applied to the problem of chatter suppression in milling of thin-walled parts. And it can monitor and control the temperature of the magnetorheological elastomer, so that the magnetorheological vibration absorption device can work stably for a long time.

[0010] One technical solution provided by the present invention is:

[0011] A milling magnetorheological vibration absorption system for thin-walled parts considering the temperature rise effect, comprising:

[0012] A magnetorheological vibration absorber assembly, which includes an annular heat dissipation layer with cold air grooves inside, and is fixedly installed on the surface of the thin-walled part to be machined as a whole;

[0013] An air-cooling assembly, which is adaptively connected to the cold air grooves and is used for air-cooling the magnetorheological vibration absorber assembly;

[0014] A control assembly, which is connected to the magnetorheological vibration absorber assembly and the air-cooling assembly, and is used for adjusting and controlling the current magnitude of the magnetorheological vibration absorber assembly and the on-off of the air-cooling assembly.

[0015] A further technical solution of the present invention is: the magnetorheological vibration absorber assembly further includes an upper end cover, a lower end cover, an excitation coil, a cylindrical magnetorheological elastomer and bolts. The upper end cover is fixedly installed on the lower end cover to form an absorber housing; the cylindrical magnetorheological elastomer is installed in the middle of the absorber housing, and an annular heat dissipation layer is arranged outside it. The upper end of the annular heat dissipation layer passes through the arc-shaped hole at the top of the upper end cover and is connected to the air-cooling assembly, and its lower end is embedded into the lower end cover and is communicated with the outside through an air vent groove in the circumferential direction; the excitation coil is wound on the surface of the annular heat dissipation layer, and its wire ends are led out through the wire passing holes on the side surface of the lower end cover and are connected to the control assembly.

[0016] A further technical solution of the present invention is: the working mode of the magnetorheological vibration absorber is the extrusion type.

[0017] A further technical solution of the present invention is: the side surface of the upper end cover is provided with a kidney-shaped hole, and the lower end cover is provided with a threaded hole corresponding to the side surface of the upper end cover. The bolt passes through the kidney-shaped hole of the upper end cover and cooperates with the threaded hole of the lower end cover to form an absorber housing; the number of the arc-shaped hole at the top of the upper end cover, the kidney-shaped hole on the side surface, the threaded hole on the side surface of the lower end cover, the air vent groove, the cold air groove and the wire passing hole is 3, and they are evenly distributed.

[0018] A further technical solution of the present invention is: the heat dissipation layer is made of aluminum alloy, a heat-conducting material with low magnetic permeability, and the inner side wall is coated with a heat-insulating material RGL-NC11-800. A deformation space is reserved between the heat dissipation layer and the cylindrical magnetorheological elastomer.

[0019] A further technical solution of the present invention is: both the upper end cover and the lower end cover are made of electromagnetic pure iron DT4, a magnetic conductive material, and the excitation coil is wound with enameled copper wire.

[0020] A further technical solution of the present invention is that the air-cooling component includes: an air compressor, a voltage stabilizer, a vortex tube, a switch and a connector. The air compressor, the voltage stabilizer, the vortex tube, the switch and the connector are connected in sequence. The output end of the connector is adaptively connected to the cold air tank in the magnetorheological shock absorber assembly. The air compressor compresses the gas to generate strong air pressure, which is controlled by the voltage stabilizer, and the compressed air is input into the vortex tube. When the switch is turned on, the air flow at the cold air end of the vortex tube uniformly enters the three cold air tanks of the magnetorheological shock absorber assembly through the connector to cool the magnetorheological shock absorber.

[0021] A further technical solution of the present invention is that the control component includes:

[0022] A DC power supply for supplying power to each working component;

[0023] A signal acquisition module for acquiring the displacement signal of the workpiece and the temperature signal on the surface of the magnetorheological shock absorber;

[0024] An ADC module for converting the analog signal acquired by the signal acquisition module into a digital signal;

[0025] A control module for reading the digital signal from the ADC module, performing analysis and calculation processing according to the set control algorithm, and outputting a control signal;

[0026] A driving module includes an MOS transistor and a servo. The development board drives the MOS transistor through the output control signal to adjust the magnitude of the excitation current in the excitation coil, and drives the servo to rotate to control the on / off of the air-cooling component;

[0027] The signal acquisition module, the ADC module, the control module and the driving module are all electrically connected to the DC power supply.

[0028] A further technical solution of the present invention is that the signal acquisition module includes a laser displacement sensor, a step-down circuit, a paste-type platinum resistance temperature probe and a temperature transmitter. The laser displacement sensor acquires the displacement signal of the workpiece and outputs a voltage analog signal through the step-down circuit. The paste-type platinum resistance temperature probe is placed on the surface of the magnetorheological shock absorber, and the measured temperature signal is sent to the temperature transmitter through a lead, and the temperature transmitter then converts the temperature signal into a voltage analog signal. The control module uses a STM32F103VET6 development board.

[0029] Another technical solution provided by the present invention is:

[0030] A control method for a magnetorheological shock absorption system for thin-walled part milling considering the temperature rise effect, including the following method steps:

[0031] Step 1: In the initial state, paste the magnetorheological shock absorber on the surface of the workpiece to be processed. A temperature probe is pasted on it. A laser displacement sensor is installed at the same height as the processing position beside the workpiece to be processed. Both are connected to the development board. The development board is in the initialization state, and the switch of the air-cooling component is off;

[0032] Step 2: Use the laser displacement sensor and the temperature probe to collect the workpiece displacement signal and the magnetorheological elastomer temperature signal respectively, and convert them into electrical signals and transmit them to the ADC module of the development board;

[0033] Step 3: Based on the signals collected in Step 2, the processing module analyzes them according to the set vibration control algorithm and temperature control algorithm, and issues control instructions to drive the MOS tube and the servo respectively, controlling the magnitude of the current in the excitation coil and the on / off of the air-cooling component;

[0034] Step 3.1: The vibration control algorithm is as follows:

[0035] When the displacement and velocity directions of the workpiece are the same, and the displacement difference between the current moment and the previous moment is greater than the set threshold, the control module outputs the corresponding PWM signal to drive the MOS tube to output the corresponding voltage, and adjusts the excitation current in the coil to the maximum value;

[0036] When the displacement and velocity directions of the workpiece are opposite, and the displacement difference between the current moment and the previous moment is greater than the threshold, the current is adjusted to the minimum value;

[0037] If the displacement change between the current moment and the previous moment is small, and the displacement difference is less than the threshold, the current is not adjusted, and the current maintains the state of the previous moment.

[0038] Step 3.2: The temperature control algorithm is as follows:

[0039] When the temperature of the magnetorheological elastomer is greater than the set upper threshold and is still rising, the control module outputs the corresponding PWM signal to drive the servo to rotate, and turns on the switch of the air-cooling component; Cold air enters the heat dissipation layer of the magnetorheological shock absorber to cool the magnetorheological elastomer, achieving the purpose of maintaining the performance of the magnetorheological shock absorber;

[0040] When the temperature of the magnetorheological elastomer is less than the set lower threshold and is still dropping, the control module outputs the corresponding PWM signal to drive the servo to rotate, turns off the switch of the air-cooling component, and stops passing cold air in the heat dissipation layer;

[0041] In other cases, the control module does not output servo action instructions and maintains the current state.

[0042] Beneficial effects

[0043] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0044] (1) The magnetorheological vibration absorber with an air-cooling structure can achieve forced air-cooling of the magnetorheological elastomer by means of the annular heat dissipation layer. The upper end of the cold air groove of the annular heat dissipation layer passes through the arc-shaped hole at the top of the upper end cover and is connected to the air-cooling component, and its lower end is embedded in the lower end cover and is communicated with the outside through the ventilation groove in the circumferential direction. This structure arranges the annular heat dissipation layer between the magnetorheological elastomer and the excitation coil, which will not affect the magnetic field distribution of the magnetorheological elastomer of the vibration absorber and allows the external controller to perform forced cooling according to the real-time temperature signal.

[0045] (2) The magnetorheological vibration absorber with a vibration control component can quickly and accurately collect the vibration displacement signal of the workpiece by the laser displacement sensor, and can quickly and effectively adjust the current of the excitation coil through the current control algorithm in the control component, and can adjust the dynamic parameters of the thin-walled workpiece-magnetorheological elastomer system in real time according to the processing conditions, so as to realize the suppression of milling chatter.

[0046] (3) The magnetorheological vibration absorber with a temperature control component can monitor the temperature of the magnetorheological elastomer in real time and can control the on-off of the air-cooling device in real time through the temperature control algorithm in the control component. It greatly reduces the influence of the temperature rise effect generated by the energization and heating of the excitation coil on the frequency shift performance of the vibration absorber, so that the whole set of magnetorheological vibration absorbers can work effectively and stably for a long time. Description of the Drawings

[0047] Figure 1 is the three-dimensional structure schematic diagram of the magnetorheological vibration absorber of the present invention;

[0048] Figure 2 is the cross-sectional schematic diagram of the magnetorheological vibration absorber of the present invention;

[0049] Figure 3 is the overall working flow chart of the control component of the present invention;

[0050] Figure 4 is the schematic diagram of the vibration control algorithm principle of the present invention;

[0051] Figure 5 is the schematic diagram of the temperature control algorithm principle of the present invention. Description of the Drawings:

[0053] Among them: upper end cover 1, lower end cover 2, excitation coil 3, annular heat dissipation layer 4, cylindrical magnetorheological elastomer 5, bolt 6. Detailed Embodiments

[0054] The embodiments described below with reference to the drawings are exemplary and are intended to explain the present invention and should not be construed as limiting the present invention.

[0055] In the description of the present invention, it should be understood that the orientation or positional relationships indicated by the terms "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", etc. are based on the orientation or positional relationships shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be construed as a limitation to the present invention.

[0056] A milling magnetorheological vibration absorption system for thin-walled parts considering the temperature rise effect includes a magnetorheological vibration absorber assembly, an air cooling assembly, and a control assembly.

[0057] As Figure 1 and Figure 2 shown, it is a three-dimensional structure schematic diagram and a sectional view of the magnetorheological vibration absorber. It includes an upper end cover 1, a lower end cover 2, an excitation coil 3, an annular heat dissipation layer 4, a cylindrical magnetorheological elastomer 5, and a bolt 6. A waist-shaped hole is opened on the side of the upper end cover 1, a threaded hole is opened on the side of the lower end cover 2, and the bolt 6 passes through the waist-shaped hole of the upper end cover 1 and cooperates with the threaded hole of the lower end cover 2 to jointly form an absorber housing. The cylindrical magnetorheological elastomer 5 is installed in the absorber housing, and the annular heat dissipation layer 4 is outside it. The heat dissipation layer is provided with cold air grooves, and its upper end passes through the upper end cover 1 through an arc-shaped hole and is connected to a cooling device, and its lower end is embedded in the lower end cover and communicated with an air vent groove. The excitation coil 3 is wound around the side of the annular heat dissipation layer 4, and its wire ends are connected to the control assembly.

[0058] The air cooling assembly includes an air compressor, a pressure stabilizer, a switch, a vortex tube, and a connector. The air compressor compresses the gas to generate a strong air pressure, which is controlled by the pressure stabilizer, and the compressed air is input into the vortex tube. After the switch is turned on, the air flow at the cold air end of the vortex tube can be evenly introduced into the three cold air grooves of the heat dissipation layer of the magnetorheological vibration absorber through the connector to cool the magnetorheological vibration absorber.

[0059] As Figure 3 shown, it is a schematic diagram of the entire magnetorheological vibration absorption system, which is used to implement the following working process:

[0060] 1) Initial state: The magnetorheological vibration absorber is pasted on the surface of the workpiece to be machined, and a temperature probe is pasted on it. A laser displacement sensor is installed at the same height as the machining position beside the workpiece, and both are connected to the development board. The development board is in the initialization state, and the switch of the air cooling assembly is off.

[0061] 2) The laser displacement sensor and the temperature probe respectively collect the initial displacement signal x0 of the workpiece and the initial temperature signal T0 of the magnetorheological elastomer.

[0062] 3) After the milling process starts, the laser displacement sensor and the temperature probe collect the workpiece displacement signal and the magnetorheological elastomer temperature signal at certain time intervals respectively. The current displacement of the workpiece is denoted as x c , and the displacement at the previous moment is denoted as x l . The current temperature of the magnetorheological elastomer is denoted as T c , and the temperature at the previous moment is T l . The above displacement and temperature signals are converted into electrical signals and transmitted to the ADC module of the development board.

[0063] 4) Based on the signals collected in steps 2) and 3), the development board processor analyzes them according to the set vibration control algorithm and temperature control algorithm, and then issues corresponding control instructions to drive the MOS transistor and the servo respectively, controlling the magnitude of the current in the excitation coil and the on / off of the air-cooling component.

[0064] 4.1) Vibration control algorithm

[0065] As Figure 4 shown, it is the schematic diagram of the vibration control algorithm, and the main process is as follows:

[0066] When the displacement and velocity directions of the workpiece are the same, and the displacement difference between the current moment and the previous moment is greater than the set threshold δ x . The development board processor outputs a corresponding PWM signal to drive the MOS transistor to output a corresponding voltage, and adjusts the excitation current in the coil to the maximum value I max . That is:

[0067] (x c -x0)(x c -x l ) > 0 and |x c -x l | > δ x → I = I max

[0068] When the displacement and velocity directions of the workpiece are opposite, and the displacement difference between the current moment and the previous moment is greater than the threshold δ x , then the current is adjusted to the minimum value I min . That is:

[0069] (x c -x0)(x c -x l ) < 0 and |x c -x l | > δ x → I = I min

[0070] If the displacement change between the current moment and the previous moment is small, and the displacement difference is less than the threshold δx If not, the current remains unchanged at the previous moment I. l That is:

[0071] |x c -x l | < δ x → I = I i

[0072] 4.2) Temperature control algorithm

[0073] As Figure 5 shown, it is the schematic diagram of the vibration control algorithm, and the main process is as follows:

[0074] When the current temperature T of the magnetorheological elastomer c is greater than the set upper threshold T max and is still rising, the controller outputs the corresponding PWM signal to drive the servo to rotate and turn on the air-cooling component switch. The cold air enters the cold air tank in the heat dissipation layer of the magnetorheological shock absorber to cool the magnetorheological elastomer, achieving the purpose of maintaining the performance of the magnetorheological shock absorber. That is:

[0075] T c -T max > 0 and T c -T l > 0 → The servo can turn on the air-cooling switch

[0076] When the current temperature T of the magnetorheological elastomer c is less than the set lower threshold T min and is still falling, the controller outputs the corresponding PWM signal to drive the servo to rotate and turn off the air-cooling component switch, and the cold air supply in the cold air tank of the heat dissipation layer stops. That is:

[0077] T c -T min < 0 and T c -T l < 0 → The servo can turn off the air-cooling switch

[0078] In other cases, the controller does not output servo action instructions and maintains the current state.

[0079] Although the embodiments of the present invention have been shown and described above, it can be understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Those of ordinary skill in the art can make changes, modifications, substitutions, and variations to the above embodiments within the scope of the present invention without departing from the principles and purposes of the present invention.

Claims

1. A milling magnetorheological vibration absorption system for thin-walled parts considering temperature rise effect, characterized in that: The system includes: A magnetorheological shock absorber assembly, which includes an annular heat dissipation layer with cold air grooves inside, and is integrally fixedly installed on the surface of the thin-walled workpiece to be processed; An air cooling assembly, which is adaptively connected to the cold air grooves and is used to air-cool the magnetorheological shock absorber assembly; A control assembly, which is connected to the magnetorheological shock absorber assembly and the air cooling assembly, and is used to adjust and control the magnitude of the current of the magnetorheological shock absorber assembly and the on / off of the air cooling assembly; The magnetorheological shock absorber assembly further includes: an upper end cover, a lower end cover, an excitation coil, a cylindrical magnetorheological elastomer, and bolts. The upper end cover is fixedly installed on the lower end cover to form a shock absorber housing; the cylindrical magnetorheological elastomer is installed in the middle of the shock absorber housing, and an annular heat dissipation layer is arranged outside it. The upper end of the annular heat dissipation layer passes through the arc-shaped hole at the top of the upper end cover and is connected to the air cooling assembly, and the lower end is embedded in the lower end cover and is communicated with the outside through an air vent groove in the circumferential direction; the excitation coil is wound on the surface of the annular heat dissipation layer, and its wire head is led out through the wire passing hole on the side of the lower end cover and is connected to the control assembly.

2. The milling magnetorheological vibration absorption system for thin-walled parts considering the temperature rise effect according to claim 1, characterized in that: The air cooling assembly includes: an air compressor, a voltage stabilizer, a vortex tube, a switch, and a connector. The air compressor, the voltage stabilizer, the vortex tube, the switch, and the connector are connected in sequence. The output end of the connector is adaptively connected to the cold air grooves in the magnetorheological shock absorber assembly. The air compressor compresses the gas to generate strong air pressure, which is controlled by the voltage stabilizer. The compressed air is input into the vortex tube; when the switch is turned on, the air flow at the cold air end of the vortex tube uniformly enters the cold air grooves of the magnetorheological shock absorber assembly through the connector to cool the magnetorheological shock absorber.

3. A thin-walled part milling magnetorheological vibration absorption system considering temperature rise effect according to claim 1, characterized in that: The control assembly includes: A DC power supply, which is used to supply power to each working component; A signal acquisition module, which is used to acquire the displacement signal of the workpiece and the temperature signal on the surface of the magnetorheological shock absorber; An ADC module, which is used to convert the analog signal acquired by the signal acquisition module into a digital signal; A control module, which is used to read the digital signal from the ADC module, perform analysis and calculation processing according to the set control algorithm, and output a control signal; the control module uses a STM32F103VET6 development board; A drive module, which includes MOS tubes and a servo. The development board drives the MOS tubes through the output control signal to adjust the magnitude of the excitation current in the excitation coil, and drives the servo to rotate to control the on / off of the air cooling assembly; The signal acquisition module, the ADC module, the control module, and the drive module are all electrically connected to the DC power supply.

4. A thin-walled part milling magnetorheological vibration absorption system considering temperature rise effect according to claim 3, characterized in that: The signal acquisition module includes a laser displacement sensor, a step-down circuit, a paste-type platinum resistance probe, and a temperature transmitter. The laser displacement sensor acquires the displacement signal of the workpiece and outputs a voltage analog signal through the step-down circuit; the paste-type platinum resistance probe is placed on the surface of the magnetorheological shock absorber, and the measured temperature signal is sent to the temperature transmitter through a lead, and the temperature transmitter then converts the temperature signal into a voltage analog signal.

5. A thin-walled part milling magnetorheological vibration absorption system considering the temperature rise effect according to claim 1, characterized in that: The working mode of the magnetorheological shock absorber is the extrusion type.

6. The milling magnetorheological vibration absorption system for thin-walled parts considering the temperature rise effect according to claim 1, wherein: The side surface of the upper end cover is provided with a waist-shaped hole, and the lower end cover is provided with a threaded hole corresponding to the position of the side surface of the upper end cover. The bolt passes through the waist-shaped hole of the upper end cover and is matched with the threaded hole of the lower end cover to form the absorber housing. The number of the arc-shaped holes at the top end of the upper end cover, the waist-shaped holes on the side surface, the threaded holes on the side surface of the lower end cover, the ventilation grooves, the cold air grooves and the wire passing holes are all 3, and they are evenly distributed.

7. The thin-walled part milling magnetorheological vibration absorption system considering the temperature rise effect according to claim 1, characterized in that: The inner side wall of the annular heat dissipation layer is coated with a heat insulation material RGL-NC11-800, and a deformation space is reserved between the annular heat dissipation layer and the cylindrical magnetorheological elastomer.

8. A thin-walled part milling magnetorheological vibration absorption system considering temperature rise effect according to claim 1, characterized in that: Both the upper end cover and the lower end cover are made of a magnetic conductive material, electrolytic iron DT4 for electrical engineering, and the exciting coil is wound with enameled copper wire.

9. A control method for a milling magnetorheological absorber system for thin-walled parts considering the temperature rise effect according to any one of claims 1-8, comprising the following method steps: Step 1: In the initial state, the magnetorheological absorber is pasted on the surface of the workpiece to be machined, and a temperature probe is pasted thereon. A laser displacement sensor is installed at the same height as the machining position beside the workpiece to be machined, and both are connected to the development board. The development board is in the initialization state, and the switch of the air-cooling component is turned off. Step 2: The laser displacement sensor and the temperature probe are used to collect the workpiece displacement signal and the magnetorheological elastomer temperature signal respectively, and convert them into electrical signals and transmit them to the ADC module of the development board. Step 3: Based on the signals collected in Step 2, the processing module analyzes them according to the set vibration control algorithm and temperature control algorithm, and issues control instructions to drive the MOS tube and the servo respectively, so as to control the magnitude of the current in the exciting coil and the on / off of the air-cooling component. The vibration control algorithm is as follows: When the displacement and velocity of the workpiece are in the same direction, and the displacement difference between the current moment and the previous moment is greater than the set threshold, the control module outputs a corresponding PWM signal to drive the MOS tube to output a corresponding voltage, and adjusts the exciting current in the coil to the maximum value. When the displacement and velocity of the workpiece are in the opposite direction, and the displacement difference between the current moment and the previous moment is greater than the threshold, the current is adjusted to the minimum value. If the displacement change between the current moment and the previous moment is not large, and the displacement difference is less than the threshold, the current is not adjusted and remains in the state of the previous moment. The temperature control algorithm is as follows: When the temperature of the magnetorheological elastomer is greater than the set upper threshold and is still rising, the control module outputs a corresponding PWM signal to drive the servo to rotate, and turns on the switch of the air-cooling component; cold air enters the heat dissipation layer of the magnetorheological absorber to cool the magnetorheological elastomer, so as to achieve the purpose of maintaining the performance of the magnetorheological absorber. When the temperature of the magnetorheological elastomer is less than the set lower threshold and is still decreasing, the control module outputs a corresponding PWM signal to drive the servo to rotate, turns off the switch of the air-cooling component, and stops passing cold air in the heat dissipation layer. In other cases, the control module does not output a servo action instruction and maintains the current state.

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