Intelligent magneto-rheological damper with state self-sensing and cooperative reset functions

Abstract

The application discloses an intelligent magneto-rheological damper with state self-sensing and cooperative reset functions, and relates to the technical field of dampers. The application discloses an intelligent magneto-rheological damper with state self-sensing and cooperative reset functions, and relates to the technical field of dampers. The piston is connected with a piston rod at one end and is in contact with a sensor component at the other end. A plurality of coils and a plurality of magnetic conductive rings are arranged alternately along the axial direction of the sleeve and are fixed on the inner wall of the sleeve. The sensor component is built-in at the bottom of the damper to directly sense the pressure of the piston without an external sensor, so that the system structure is simplified, signal transmission delay is eliminated, and real-time and direct control in a true sense is realized.

Description

Technical Field

[0001] This invention relates to the field of damper technology, specifically to an intelligent magnetorheological damper with state self-sensing and collaborative reset functions. Background Technology

[0002] This invention belongs to the field of intelligent structure vibration reduction and hydraulic control technology, specifically relating to a magnetorheological fluid damper with self-sensing pressure regulation function and integrated mechanical active reset structure. Magnetorheological dampers are widely used in vehicle suspension, building vibration isolation, and precision robot joints due to their fast response, low energy consumption, and continuously adjustable damping force. However, existing magnetorheological dampers still have significant shortcomings in terms of integration. First, most dampers require externally installed displacement or force sensors to obtain feedback signals, which not only increases the complexity and size of the system but also causes a perceptible time delay in the control system due to the excessively long signal transmission chain. Second, traditional dampers often lack an effective internal automatic reset mechanism; after experiencing large displacement impacts, the piston often cannot quickly return to its equilibrium position using its own structure, affecting subsequent vibration reduction effects. Furthermore, magnetic leakage caused by unreasonable electromagnetic circuit design also limits the output range of the damping force. Furthermore, existing magnetorheological dampers with built-in reset springs or pressure sensors still suffer from the following unresolved technical defects: the sensing signal is only used for damping adjustment and does not participate in the reset decision, resulting in the need for external control signals or reliance on purely mechanical reset during the reset phase, leading to slow response and residual damping resistance; there is a lack of mechanical decoupling between the spring and the damper fluid chamber, making it impossible to distinguish the contributions from fluid damping and spring elasticity in the pressure signal, thus preventing closed-loop correction; the multi-stage electromagnetic circuit and spring reset mechanism are independent of each other, failing to form a coordinated control of "magnetic field-rheology-elasticity", which limits the overall dynamic performance of the system.

[0003] Magnetorheological fluid (MRF) is a smart fluid material composed of micron-sized soft magnetic particles uniformly dispersed in an insulating carrier fluid. Its significant characteristic is that under the influence of an external magnetic field, its rheological properties (such as apparent viscosity and shear yield stress) can undergo large, reversible changes within milliseconds. Based on this principle, magnetorheological dampers have become one of the core devices in the field of semi-active vibration control due to their outstanding advantages such as fast response speed, continuously adjustable damping force, low energy consumption, and large output force.

[0004] Magnetorheological dampers are widely used in vehicle suspensions, building vibration isolation, and precision robot joints due to their fast response, low energy consumption, and continuously adjustable damping force. However, existing magnetorheological dampers still have significant shortcomings in terms of integration. First, most dampers require externally installed displacement or force sensors to obtain feedback signals, which not only increases the complexity and size of the system but also causes a noticeable time delay in the control system due to the excessively long signal transmission chain. Second, traditional dampers often lack an effective internal automatic reset mechanism. After experiencing large displacement impacts, the piston often cannot quickly return to the equilibrium position on its own, affecting the subsequent vibration reduction effect. In addition, magnetic leakage caused by unreasonable electromagnetic circuit design also limits the output range of the damping force. Summary of the Invention

[0005] The purpose of this invention is to provide an intelligent magnetorheological damper with state self-sensing and collaborative reset functions. This damper integrates a pressure sensing element inside the damper to realize direct measurement of vibration signals and real-time closed-loop control of damping force. At the same time, the built-in spring realizes the automatic reset of the piston, which simplifies the system structure and improves the response speed and reliability.

[0006] The objective of this invention can be achieved through the following technical solutions: A smart magnetorheological damper with state self-sensing and collaborative reset functions includes a sleeve and a piston assembly disposed inside the sleeve, wherein the sleeve is filled with magnetorheological fluid. The piston assembly includes: The piston has one end connected to the piston rod and the other end in contact with the sensor components. Multiple coils and multiple magnetic rings are arranged alternately along the axial direction of the sleeve and fixed on the inner wall of the sleeve. The magnetic rings and the coils are located on the outer peripheral surface of the piston and the sensor component. The signal output terminal of the sensor component is connected to an external controller, which is used to adjust the magnitude of the excitation current of the coil.

[0007] As a further aspect of the present invention: an annular working gap is formed between the outer circumferential surface of the piston and the inner diameter surface of the magnetic ring, and the width of the gap is 1mm.

[0008] As a further aspect of the present invention: the magnetic ring is made of DT4C electrical pure iron material, and its magnetic saturation strength is not less than 2.1T; the sleeve is made of 45# steel after quenching and tempering treatment.

[0009] As a further aspect of the present invention: the sensor component is a high-frequency piezoelectric pressure sensor, the sensing surface of which is opposite to the bottom axis of the piston, and is used to capture the instantaneous compressive stress generated on the bottom liquid column and the end of the spring during the piston's downward movement; the spring is a compression spring made of alloy spring steel, and its pre-compression is precisely compensated by adjusting the axial position of the end cap with bolts.

[0010] As a further aspect of the present invention: the coil is wound with high-strength polyimide enameled wire and externally encapsulated with thermally conductive epoxy resin.

[0011] As a further aspect of the present invention: the upper and lower ends of the inner wall of the sleeve are respectively provided with an upper inner ring and a lower inner ring. The lower inner ring and the upper inner ring are made of non-magnetic materials such as aluminum alloy or austenitic stainless steel, so as to isolate the magnetic ring from the direct magnetic short circuit between the sleeve bottom and top in space, and force the magnetic field lines to cross the magnetorheological fluid in the annular working gap.

[0012] As a further aspect of the present invention: a spring is fixedly installed on the bottom inner wall of the sleeve, a sensor component is fixedly installed on the spring, and the top of the sleeve is connected to the end cap by bolts.

[0013] As a further aspect of the present invention: the volume fraction of soft magnetic particles in the magnetorheological fluid is between 25% and 40%, and its zero magnetic field viscosity is less than 0.5 Pa·s.

[0014] As a further aspect of the present invention: the spring forms a series force transmission path with the magnetorheological fluid damping force during compression; the pressure signal P(t) measured by the sensor component satisfies: Where F damping (t) represents the damping force generated by the magnetorheological fluid, F. spring (t) represents the elastic force of the spring; The controller decouples F in real time by comparing P(t) with the pre-stored spring stiffness curve. damping (t) and independently correct the coil current to achieve active decoupling control of damping force and elastic force.

[0015] To further illustrate the self-sensing and decoupling process of the composite pressure signal, an equivalent simulation of the damper's force response under simplified impact load was performed. External impact load. After the action, the built-in pressure sensor obtains a filtered composite pressure signal that matches the trend of external load changes. Based on the equivalent stiffness relationship of the reset spring, the composite pressure signal can be decomposed into a spring force estimate. And magnetorheological damping force estimation This allows us to characterize the relative contributions of the spring's elastic effect and the magnetorheological damping effect at different stages. In the initial stage of the impact, the estimated damping force is relatively large, indicating that the system mainly relies on the magnetorheological fluid for impact suppression; as the external load decays, the spring force component gradually becomes dominant, providing elastic restoring force for subsequent reset.

[0016] As a further aspect of the present invention, the control method of the intelligent magnetorheological damper includes the following steps: Step 1: The sensing component collects the composite pressure signal generated by the piston compressing the spring and the sensing component in real time; Step 2: The external controller performs multi-parameter analysis on the composite pressure signal, including amplitude, rate of change, and duration: it linearly adjusts the coil current based on the pressure amplitude to control the steady-state damping force; when the pressure rate of change exceeds a preset threshold, it is determined to be an impact load, and the coil current is increased to the preset value in advance; when the pressure signal returns to zero and the duration exceeds the reset delay threshold, it is determined that the external excitation has disappeared, and the coil current is actively reduced to the reset current value. Step 3: Under the reset current value, the viscosity of the magnetorheological fluid is lower than the critical value, and the spring pushes the piston and piston rod to quickly reset to the initial position.

[0017] The piston displacement peak is largest in the fixed low-damping mode, indicating insufficient suppression of external impacts. Although the fixed high-damping mode can reduce the displacement peak, the large damping force results in significant residual damping during the reset phase, leading to a slower piston return speed. Self-sensing coordinated control suppresses the piston displacement peak by increasing the coil current during the impact phase and decreasing it after excitation decay, while simultaneously enabling a faster return to near the initial position during the reset phase, thus balancing impact buffering and rapid reset.

[0018] The beneficial effects of this invention are: 1. High integration and self-sensing: By embedding the sensor components in the bottom of the damper, the pressure of the piston can be directly sensed without the need for external sensors, which simplifies the system structure, eliminates signal transmission delay, and achieves true real-time and direct control.

[0019] 2. Automatic reset function: The built-in spring provides the reset force, ensuring that the damper can automatically return to the initial working position after the external excitation disappears. This simplifies the system design and improves its applicability in scenarios with unilateral force or requiring precise positioning.

[0020] 3. Compact and reliable structure: The excitation coil and the magnetic ring are both fixed to the inner wall of the sleeve. The piston structure is simple and does not require complex dynamic seals and internal wiring, which significantly improves the reliability and service life of the damper.

[0021] 4. Intelligent adjustable damping force: By monitoring the pressure in real time through sensing components and linearly adjusting the coil current, the damping force can be adaptively adjusted over a wide range according to the external load, resulting in excellent vibration reduction effect. Attached Figure Description

[0022] The invention will now be further described with reference to the accompanying drawings.

[0023] Figure 1 This is a schematic diagram of the overall structure of the present invention; Figure 2 This is an axial sectional view of the present invention; Figure 3 This is a schematic diagram showing the relationship between the magnetic field generating component and the piston. Figure 4 This is the control flowchart of the present invention; Figure 5 Diagram illustrating the self-sensing and collaborative reset mechanism of an intelligent magnetorheological damper. Figure 6 This is a schematic diagram of a state self-aware closed-loop association. Figure 7 A diagram showing the decoupling relationship between external shock and self-sensed pressure; Figure 8 A comparison chart of piston displacement response under different control methods; Figure 9 A comparison chart of the specified current and the actual current.

[0024] In the diagram: 1. Sleeve; 2. Lower inner ring; 3. Spring; 4. Magnetic ring; 5. Sensor component; 6. Coil; 7. Piston; 8. Upper inner ring; 9. Bolt; 10. End cap; 11. Piston rod; 12. Wire. Detailed Implementation

[0025] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0026] Please see Figures 1-2 As shown, the present invention is an intelligent magnetorheological damper with state self-sensing and collaborative reset functions, including a sleeve 1, a lower inner ring 2, an upper inner ring 8, a spring 3, a magnetic ring 4, a sensor component 5, a coil 6, a piston 7, a bolt 9, an end cap 10, a piston rod 11, and a wire 12. Sleeve 1 is the outer shell of this damper, with a cylindrical structure. Its interior forms a sealed cavity filled with magnetorheological fluid. The top of sleeve 1 is connected to end cap 10 via bolts 9. On the inner wall of sleeve 1, along its axial direction, three magnetic rings 4 and two coils 6 are arranged alternately in the following order: magnetic ring 4 - coil 6 - magnetic ring 4 - coil 6 - magnetic ring 4. The magnetic rings 4 are made of electrical pure iron and are used to guide magnetic lines of force. Specifically, the magnetic rings and coils are tightly fitted together, forming a multi-stage magnetic field generating assembly. This design fixes all excitation components to sleeve 1, avoiding the complexity of a piston structure.

[0027] A spring 3 is installed on the bottom inner wall of the sleeve 1. One end of the spring 3 is fixedly connected to the bottom of the sleeve, and the other end extends freely and is connected to the sensor component 5 to provide a restoring force for the piston. The piston rod 11 is a long rod, with one end extending from the open end of the sleeve 1 for connection to an external load requiring vibration damping; the other end extends into the sleeve and is fixedly connected to the piston 7. An annular working gap, 1mm wide, is formed between the outer circumferential surface of the piston 7 and the inner diameter surface of the magnetic ring 4. This gap is the core area for the damping effect of the magnetorheological fluid, and the magnetic circuit can always effectively cover the working gap. The piston rod 11 has a hollow structure for the insertion and installation of the wire 12, ensuring its aesthetics and practicality. A sensor component 5, a pressure sensor, is mounted at the bottom of the piston 7. It is positioned at the center of the bottom of the sleeve and directly senses the pressure signal transmitted from the piston 7. The signal output of the sensor component 5 is connected to an external controller, which adjusts the excitation current of the coil 6.

[0028] The magnetic ring 4 is made of DT4C electrical pure iron material, and its magnetic saturation strength is not less than 2.1T; the sleeve 1 is made of 45# steel and heat treated to meet the principle of magnetic flux continuity and prevent magnetic saturation.

[0029] Sensor component 5 is a high-frequency piezoelectric pressure sensor. Its sensing surface is opposite to the bottom axis of piston 7. It is used to capture the instantaneous compressive stress generated on the bottom liquid column and the end of spring 3 during the downward movement of piston 7. Spring 3 is a compression spring made of alloy spring steel. Its pre-compression is precisely compensated by adjusting the axial position of end cap 10 through bolt 9.

[0030] Coil 6 is wound with high-strength polyimide enameled wire and encapsulated with thermally conductive epoxy resin. The number of turns of coil 6 meets the requirements of the dynamic range of damping force; at the same time, it ensures that the symmetry of the magnetic circuit distribution is not affected.

[0031] The upper and lower ends of the inner wall of the sleeve 1 are respectively provided with an upper inner ring 8 and a lower inner ring 2. The lower inner ring 2 and the upper inner ring 8 are made of non-magnetic materials such as aluminum alloy or austenitic stainless steel, which are used to isolate the magnetic ring 4 from the direct magnetic short circuit between the bottom and top of the sleeve 1 in space, and force the magnetic field lines to cross the magnetorheological fluid in the annular working gap.

[0032] The volume fraction of soft magnetic particles in the magnetorheological fluid is between 25% and 40%, and its zero magnetic field viscosity is less than 0.5 Pa·s, so as to ensure low starting resistance of the system under no-load conditions.

[0033] During compression, spring 3 forms a series force transmission path with the damping force of the magnetorheological fluid; the pressure signal P(t) measured by sensor component 5 satisfies: Where F damping (t) represents the damping force generated by the magnetorheological fluid, F. spring (t) represents the elastic force of the spring; The controller decouples F in real time by comparing P(t) with the pre-stored spring stiffness curve. damping (t) and independently correct the coil current to achieve active decoupling control of damping force and elastic force.

[0034] To further illustrate the self-sensing and decoupling process of the composite pressure signal, an equivalent simulation of the damper's force response under simplified impact load was performed. (See reference...) Figure 7 As shown. External impact load. After the action, the built-in pressure sensor obtains a filtered composite pressure signal that matches the trend of external load changes. Based on the equivalent stiffness relationship of the reset spring, the composite pressure signal can be decomposed into a spring force estimate. And magnetorheological damping force estimation This allows us to characterize the relative contributions of the spring's elastic effect and the magnetorheological damping effect at different stages. In the initial stage of the impact, the estimated damping force is relatively large, indicating that the system mainly relies on the magnetorheological fluid for impact suppression; as the external load decays, the spring force component gradually becomes dominant, providing elastic restoring force for subsequent reset.

[0035] See Figure 4 As shown, pressure sensor 5 detects the composite pressure signal P(t) transmitted from piston 7 and transmits it to the controller. The controller performs real-time analysis on three parameters of P(t): amplitude, first derivative dP / dt, and zero-return duration. See Figure 6As shown, the state self-sensing process of this invention forms a closed-loop link consisting of mechanical force, pressure sensing, state recognition, current regulation, magnetic field modulation, and low-resistance reset. The external impact load is first transmitted to the pressure sensor through the piston, which directly obtains the composite pressure signal. The controller analyzes the amplitude, rate of change, and zero-return trend of this signal and adjusts the coil current accordingly. The coil current further alters the magnetic field strength in the working gap, causing the magnetorheological fluid damping force to adaptively change with the external load state. After the external excitation disappears, the controller reduces the current to the reset current, making the magnetorheological fluid less viscous, which, in conjunction with the reset spring, completes the piston return.

[0036] When dP / dt exceeds the preset impact threshold, it is determined to be an impact load, and the controller immediately presets the coil current to a high value (feedforward control). When P(t) is stable and dP / dt is low, the current is linearly adjusted according to the magnitude of P(t) (feedback control). When P(t) is below the noise threshold and lasts for more than 10ms, the excitation is determined to be gone. The controller then forces the coil current to be reduced to the reset current (approximately 5% of the maximum operating current) to minimize the viscosity of the magnetorheological fluid.

[0037] The controller outputs a PWM control signal to the power driver, independently controlling the current of each coil 6 to achieve smooth switching between the three modes mentioned above. (See also...) Figure 9 As shown, the controller calculates the command current based on the composite pressure signal. The actual coil current I exhibits a certain lag due to the dynamic characteristics of the coil inductance and power drive circuit, but it can generally follow the changes in the command current. In the initial stage of the impact, the command current rises rapidly, causing the damping force of the magnetorheological fluid to increase rapidly; as the external excitation gradually decays, the command current decreases, and the actual current drops to a lower level, thereby restoring the magnetorheological fluid to a low viscosity state and providing a low-resistance environment for spring reset.

[0038] See Figures 1-4 As shown, the control method of this intelligent magnetorheological damper includes the following steps: Step 1: The sensing component 5 collects the composite pressure signal generated by the piston 7 compressing the spring 3 and the sensing component 5 in real time; Step 2: The external controller performs multi-parameter analysis on the composite pressure signal, including amplitude, rate of change, and duration: Based on the pressure amplitude, the current of coil 6 is linearly adjusted to control the steady-state damping force; if the pressure rate of change exceeds a preset threshold, it is determined to be an impact load, and the coil current is increased to the preset value in advance; if the pressure signal returns to zero and the duration exceeds the reset delay threshold, it is determined that the external excitation has disappeared, and the coil current is actively reduced to the reset current value. Step 3: Under the reset current value, the viscosity of the magnetorheological fluid is below the critical value, and spring 3 pushes piston 7 and piston rod 11 to quickly return to the initial position. (See also...) Figure 8 As shown, the piston displacement peak is largest in the fixed low-damping mode, indicating insufficient suppression of external impacts. While the fixed high-damping mode reduces the displacement peak, the sustained high damping force results in significant residual damping during the reset phase, leading to a slower piston return speed. Self-sensing coordinated control suppresses the piston displacement peak by increasing the coil current during the impact phase and decreasing it after excitation decay, while simultaneously enabling a faster return to the initial position during the reset phase. This balances impact buffering and rapid reset. The specific work process is as follows: See Figure 5 As shown, the working process of this invention can be divided into three stages: impact contact loading, self-sensing damping enhancement, and low-resistance collaborative reset. In the impact contact loading stage, an external impact load acts on the piston rod and drives the piston downwards. The bottom of the piston contacts the built-in pressure sensor, and the pressure is transmitted through the force chain of "piston-pressure sensor-reset spring-bottom of sleeve." In the self-sensing damping enhancement stage, the pressure sensor outputs a composite pressure signal. The controller judges the impact state based on the pressure amplitude and rate of change, and increases the coil current, causing the magnetic field guided by the magnetic ring to act on the magnetorheological fluid within the annular working gap, thereby increasing the yield stress and damping force of the magnetorheological fluid. In the low-resistance collaborative reset stage, after the external excitation decays or disappears, the controller reduces the coil current to the reset current, the residual damping of the magnetorheological fluid decreases, and the reset spring pushes the piston and piston rod back to their initial position.

[0039] When external vibration or load applies pressure to the piston rod 11 into the sleeve 1, the piston rod 11 drives the piston 7 to move towards the bottom of the sleeve. During the movement, the end face of the piston 7 first contacts the sensor component 5, and then compresses the spring 3. The sensor component 5 senses this pressure signal in real time and immediately generates a corresponding control current according to the magnitude of the pressure and a preset proportional relationship, outputting it to the coil 6. After the coil 6 is energized, it generates a magnetic field, which, guided by the magnetic ring 4, efficiently converges and is evenly distributed in the annular working gap between the piston 7 and the inner wall of the sleeve 1. Under the action of the magnetic field, the viscosity or shear yield stress of the magnetorheological fluid in the working gap increases instantaneously, thereby generating a significant damping force on the movement of the piston 7. The greater the external pressure, the greater the current output by the sensor component, the stronger the magnetic field, the stronger the damping effect of the magnetorheological fluid, and the greater the damping force generated, thus realizing an intelligent vibration reduction effect based on pressure regulation of the damping force.

[0040] When the external pressure disappears, piston 7 is no longer subjected to downward thrust. At this point, the compressed spring begins to release its stored elastic potential energy, pushing the piston and piston rod upward until the piston returns to its initial position, completing the automatic reset. Throughout this process, the damper integrates pressure sensing, damping force generation, and automatic reset functions, forming a complete, compact, and rapidly responsive adaptive vibration reduction system. The core innovative mechanism of this paper lies in: 1. Pressure-elastic composite sensing and multi-parameter signal analysis 2. The sensor component 5 and the return spring 3 are arranged in series axially, so that the pressure signal output by the sensor component simultaneously contains information about the fluid damping force and the spring elastic force. The controller, through joint analysis of the amplitude, first derivative (rate of change), and duration of the pressure signal, can uniquely distinguish the following three operating conditions: steady-state compression (low rate of change), transient impact (high rate of change), and spring return after excitation disappears (pressure returns to zero and continues). A single sensor can achieve the state identification that traditional solutions require a force sensor + displacement sensor + accelerometer. Active decoupling control of damping force and elastic force; Since the spring stiffness curve is known, the controller can use the formula Fdamping=P(t)-kx(t) to decouple the actual fluid damping force in real time, where x(t) is indirectly estimated through pressure signal integration. Based on this, the controller independently corrects the coil current, avoiding interference from spring nonlinearity on the damping force control accuracy.

[0041] 3. Magnetic field coordination mechanism during the reset phase In traditional built-in spring solutions, the magnetorheological fluid maintains its working viscosity during reset, generating residual damping force and slowing down the reset speed. This invention, upon detecting that the pressure signal has returned to zero, actively reduces the coil current to a "reset current value" far below the working current, approximately 5% to 10% of the working current. This reduces the magnetorheological fluid viscosity to near-zero magnetic field, allowing the spring's restoring force to be completely converted into the piston's kinetic energy, achieving rapid, low-resistance reset.

[0042] The foregoing has provided a detailed description of one embodiment of the present invention, but this description is merely a preferred embodiment and should not be construed as limiting the scope of the invention. All equivalent variations and modifications made within the scope of the claims of this invention should still fall within the patent coverage of this invention.

Claims

1. An intelligent magnetorheological damper with state self-sensing and collaborative reset functions, comprising a sleeve (1) and a piston assembly disposed within the sleeve (1), characterized in that, The sleeve (1) is filled with magnetorheological fluid; The piston assembly includes: The piston (7) has one end connected to the piston rod (11) and the other end can contact the sensor component (5); Multiple coils (6) and multiple magnetic rings (4) are arranged alternately along the axial direction of the sleeve (1) and fixed on the inner wall of the sleeve (1). The magnetic rings (4) and the coils (6) are located on the outer peripheral surfaces of the piston (7) and the sensor component (5). The signal output terminal of the sensor component (5) is connected to an external controller, which is used to adjust the magnitude of the excitation current of the coil (6).

2. The intelligent magnetorheological damper with state self-sensing and collaborative reset functions according to claim 1, characterized in that, An annular working gap is formed between the outer circumferential surface of the piston (7) and the inner diameter surface of the magnetic ring (4), and the width of the gap is 1mm.

3. The intelligent magnetorheological damper with state self-sensing and collaborative reset functions according to claim 1, characterized in that, The magnetic ring (4) is made of DT4C electrical pure iron material, and its magnetic saturation strength is not less than 2.1T; the sleeve (1) is made of 45# steel and has been heat treated.

4. The intelligent magnetorheological damper with state self-sensing and collaborative reset functions according to claim 1, characterized in that, The sensor component (5) is a high-frequency piezoelectric pressure sensor. Its sensing surface is opposite to the bottom axis of the piston (7) and is used to capture the instantaneous pressure stress generated on the bottom liquid column and the end of the spring (3) during the downward movement of the piston (7). The spring (3) is a compression spring made of alloy spring steel. Its pre-compression is precisely compensated by adjusting the axial position of the end cap (10) with bolts (9).

5. The intelligent magnetorheological damper with state self-sensing and collaborative reset functions according to claim 1, characterized in that, The coil (6) is wound with high-strength polyimide enameled wire and externally encapsulated with thermally conductive epoxy resin.

6. The intelligent magnetorheological damper with state self-sensing and collaborative reset functions according to claim 1, characterized in that, The upper and lower ends of the inner wall of the sleeve (1) are respectively provided with an upper inner ring (8) and a lower inner ring (2). The lower inner ring (2) and the upper inner ring (8) are made of non-magnetic materials such as aluminum alloy or austenitic stainless steel, which are used to isolate the direct magnetic short circuit between the magnetic ring (4) and the bottom and top of the sleeve (1) in space, and force the magnetic field lines to cross the magnetorheological fluid in the annular working gap.

7. The intelligent magnetorheological damper with state self-sensing and collaborative reset functions according to claim 1, characterized in that, A spring (3) is fixedly installed on the bottom inner wall of the sleeve (1), and a sensor component (5) is fixedly installed on the spring (3). The top of the sleeve (1) is connected to the end cap (10) by a bolt (9).

8. The intelligent magnetorheological damper with state self-sensing and collaborative reset functions according to claim 1, characterized in that, The volume fraction of soft magnetic particles in the magnetorheological fluid is between 25% and 40%, and its zero magnetic field viscosity is less than 0.5 Pa·s.

9. A smart magnetorheological damper with state self-sensing and collaborative reset functions according to claim 2, characterized in that, The spring (3) forms a series force transmission path with the magnetorheological fluid damping force during compression; the pressure signal P(t) measured by the sensor component (5) satisfies: Where F damping (t) represents the damping force generated by the magnetorheological fluid, F. spring (t) represents the elastic force of the spring; The controller decouples F in real time by comparing P(t) with the pre-stored spring stiffness curve. damping (t) and independently correct the coil current to achieve active decoupling control of damping force and elastic force.

10. The intelligent magnetorheological damper with state self-sensing and collaborative reset functions according to claim 1, characterized in that, The control method for this intelligent magnetorheological damper includes the following steps: Step 1: The sensing component (5) collects the composite pressure signal generated by the piston (7) compressing the spring (3) and the sensing component (5) in real time; Step 2: The external controller performs multi-parameter analysis on the composite pressure signal, including amplitude, rate of change, and duration: the current of the coil (6) is linearly adjusted according to the pressure amplitude to control the steady-state damping force; when the rate of change of pressure exceeds the preset threshold, it is determined to be an impact load, and the coil current is increased to the preset value in advance; when the pressure signal returns to zero and the duration exceeds the reset delay threshold, it is determined that the external excitation has disappeared, and the coil current is actively reduced to the reset current value. Step 3: Under the reset current value, the viscosity of the magnetorheological fluid is lower than the critical value, and the spring (3) pushes the piston (7) and piston rod (11) to quickly reset to the initial position.

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