Electrically-controlled magneto-rheological hydraulic flexible artificial muscle system and control method

Abstract

The invention belongs to the technical field of flexible driving and intelligent fluid control, and particularly relates to an electric control magneto-rheological hydraulic flexible artificial muscle system and a control method, the electric control magneto-rheological hydraulic flexible artificial muscle system comprises a flexible driving cavity, a magneto-rheological valve group, a hydraulic pump, an electromagnetic control system, a control unit and a fluid circulation channel; the flexible driving cavity is connected with the magnetorheological valve through a fluid circulation channel; the input end of the hydraulic pump is connected to the oil reservoir, and the output end is connected with the input end of the magnetorheological valve group; magnetorheological fluid is contained in a cavity of the magnetorheological valve group; the magneto-rheological valve group is connected with the electromagnetic control system; the electromagnetic control system is connected with the magnetorheological valve group and is used for controlling the magnetic field intensity; and the control unit is used for receiving the state signal and generating a control instruction so as to realize contraction and release of the driving cavity. The magneto-rheological driving system supports multiple control modes, multi-mode fusion control such as speed control, force control and position control can be achieved by adjusting the magnetic field intensity and the response curve, and different task requirements are met.

Description

Technical Field

[0001] The present invention belongs to the technical field of flexible drive and intelligent fluid control, in particular to an electrically controlled magnetorheological hydraulic flexible artificial muscle system and a control method thereof. Background Art

[0002] Existing robot joint drive systems primarily utilize motors coupled with rigid transmission devices such as reducers to achieve power output. While this type of drive structure offers high positioning accuracy and torque output, its rigidity limits the system's flexibility and safety, making it difficult to meet the flexibility and compliance requirements of human-robot collaboration and precision manipulation. Consequently, flexible drive technology has become a research hotspot.

[0003] Currently, common actuation methods include pneumatic artificial muscles and hydraulic drive systems. Pneumatic artificial muscles have attracted attention due to their lightweight and simple structure. However, traditional pneumatic control systems have significant limitations in flow regulation and force control accuracy, primarily due to the compressibility of the gas and the limited response rate of the pneumatic valve. Hydraulic actuation offers greater force output capabilities, but traditional hydraulic systems have complex structures, limited control accuracy, and high energy consumption and maintenance costs.

[0004] Magnetorheological technology, a novel intelligent material control method, has demonstrated outstanding performance in the field of fluid control in recent years. Its core principle lies in the rapid and reversible change of rheological properties of magnetorheological fluids under the influence of an external magnetic field, thereby precisely controlling the flow resistance within the system. Based on this characteristic, magnetorheological technology provides a new solution to the problems of insufficient flow control accuracy and slow response speed in flexible drive systems, and has high potential for engineering applications and research value. Summary of the Invention

[0005] The purpose of the present invention is to provide a flexible drive module that controls the flow of magnetic fluid and thus controls artificial muscles based on the magnetic field generated by an electromagnetic coil. It adjusts the fluid resistance through the magnetic field to achieve precise flow control. It has a compact structure, simple control, and strong robustness. It is particularly suitable for miniaturized, multi-degree-of-freedom flexible robot application scenarios, so as to solve the problems of single response and insufficient flexibility of existing artificial muscles in drive control.

[0006] The technical solution adopted by the present invention to achieve the above-mentioned purpose is: an electrically controlled magnetorheological hydraulic flexible artificial muscle system, comprising: a flexible driving cavity, a magnetorheological valve, a hydraulic pump, an electromagnetic control system, a control unit and a fluid circulation channel;

[0007] The flexible driving cavity has a McKibben muscle bionic design and is made of silicone rubber. The inner wall fold structure is axially corrugated. Both ends are connected to the outside through rigid joints, and a fiber force sensor is integrated to monitor the cavity status in real time.

[0008] The output end of the flexible drive cavity is connected to the output end of the magnetorheological valve through a fluid circulation channel to generate axial contraction under pressure to drive the fluid to flow into the drive cavity; the input end of the flexible drive cavity is connected to the oil storage tank;

[0009] The input end of the hydraulic pump is connected to the oil storage tank, and the output end is connected to the input end of the magnetorheological valve group;

[0010] The magnetorheological valve assembly is used to adjust the flow resistance of the magnetorheological fluid through a magnetic field; the magnetorheological fluid is contained in a cavity of the magnetorheological valve assembly; the magnetorheological valve assembly is connected to an electromagnetic control system to generate a magnetic field to act on the magnetorheological fluid;

[0011] The electromagnetic control system is connected to the magnetorheological valve group and is used for the constitutive model based on Maxwell's equations and magnetorheological fluid to control the magnetic field strength by adjusting the duty cycle of the input current;

[0012] The control unit is used to receive status signals and generate control instructions to achieve the contraction and release of the drive cavity.

[0013] The magnetorheological valve assembly is provided with one, including: a valve body, a magnetorheological fluid flow channel, an electromagnetic coil and a storage chamber;

[0014] The magnetorheological fluid flow channel is designed as a channel with a uniform slit, attached to the inner wall of the valve body, and the slit width is: 0.01-5mm;

[0015] A storage chamber is provided in the valve body, and magnetorheological fluid is contained in the storage chamber. The input end of the storage chamber is connected to the hydraulic pump, and the output end is connected to the flexible driving chamber through a fluid circulation channel.

[0016] The electromagnetic coil is arranged around the inner side of the valve body and is connected to the electromagnetic control system to form an inlet magnetorheological valve controlled flexible artificial muscle.

[0017] The magnetorheological valve assembly is provided with one, and the external magnetorheological valve is installed at the rigid connection of the artificial muscle to form an integral structure with the artificial muscle, thereby forming an integrated magnetorheological valve-controlled flexible artificial muscle.

[0018] There are multiple magnetorheological valve groups, each comprising: a valve body, a magnetorheological fluid flow channel and an electromagnetic coil;

[0019] The magnetorheological fluid flow channel is designed as a channel with a uniform slit, which is attached to the inner wall of the valve body and has a slit width of 0.01-5mm; a storage cavity is provided in the valve body;

[0020] Each storage cavity is arranged in parallel, and the input end of each storage cavity is connected to the hydraulic pump, and the output end is connected to a flexible drive cavity;

[0021] The electromagnetic coil is arranged around the inner side of the valve body and is connected to the electromagnetic control system to form a distributed valve-controlled multi-cavity flexible artificial muscle.

[0022] There are four magnetorheological valve groups, each comprising: a valve body, a magnetorheological fluid flow channel and an electromagnetic coil;

[0023] The magnetorheological fluid flow channel is designed as a channel with a uniform slit, which is attached to the inner wall of the valve body and has a slit width of 0.01-5mm; a storage cavity is provided in the valve body;

[0024] The storage chambers of the four magnetorheological valve groups are cross-connected in parallel to form a cross-shaped arrangement; when the artificial muscle needs to be stretched, the second magnetorheological valve and the fourth magnetorheological valve are closed, the first magnetorheological valve and the third magnetorheological valve are connected, and the fluid circulates to the oil reservoir through the fluid circulation channel, thereby achieving stretching of the artificial muscle; when the artificial muscle needs to be compressed, the first magnetorheological valve and the third magnetorheological valve are closed, the second magnetorheological valve and the fourth magnetorheological valve are opened, and the fluid circulates to the oil reservoir through the fluid circulation channel;

[0025] The electromagnetic coil is arranged around the outside of the valve body and is connected to the electromagnetic control system to form a cross-type bidirectional tension and compression magnetorheological valve-controlled flexible artificial muscle.

[0026] The control unit includes: a microcontroller and a pressure sensor and a position sensor connected thereto;

[0027] The pressure sensor is installed inside the flexible driving cavity, at the input end or output end of the guide pipe or the magnetorheological valve group, and is used to monitor the hydraulic pressure changes of the driving cavity in real time;

[0028] The position sensor is integrated into the rigid joints at both ends of the flexible drive cavity, the inner wall wrinkle structure area or the external load connection point, and detects deformation or displacement through a flexible fiber force sensor;

[0029] The pressure sensor operates based on the piezoresistive effect or the piezoelectric effect, and the position sensor operates based on the strain effect or the capacitance change. The sensor signal is input into the microcontroller after analog-to-digital conversion to form a closed-loop feedback control.

[0030] The magnetorheological fluid is a suspension of carbon iron particles with a particle concentration of 30% and a dynamic yield stress of 80 kPa;

[0031] A carbon iron particle suspension comprising dispersed phase particles, a carrier liquid and additives;

[0032] The dispersed phase particles are composite soft magnetic particles whose surface is coated with nano-oxides of SiO2 or Al2O3, with carbonyl iron powder as the matrix, and the nano-shell coating technology is used to enhance the oxidation resistance and dispersibility of the particles.

[0033] The carrier liquid is based on polysiloxane and is fine and has no sedimentation;

[0034] The additives include silica nanoparticles, a dispersant, an anti-settling agent, an anti-wear agent, and a surfactant added in sequence to improve the sedimentation stability, redispersibility, zero-field viscosity, and shear yield strength of the MRF.

[0035] A control method for an electrically controlled magnetorheological hydraulic flexible artificial muscle system comprises the following steps:

[0036] Step S1: receiving an external input desired contraction force or displacement signal and generating a corresponding control target;

[0037] Step S2: obtaining the pressure, deformation and position data of the driving flexible driving cavity through sensors, and providing real-time feedback of the output state of the artificial muscle through flexible fiber force sensors;

[0038] Step S3: Based on the PID algorithm and the feedback control model, combined with the difference between the sensor data and the target signal, the input current adjustment amount of the electromagnetic control system is calculated;

[0039] Step S4: adjusting the current duty cycle input to the magnetorheological valve assembly through the electromagnetic control system, dynamically changing the intensity of the magnetic field, and controlling the driving force of the magnetorheological fluid between the storage cavity and the driving flexible driving cavity;

[0040] Step S5: adjusting the cavity pressure of the flexible driving cavity by changing the flow rate of the magnetorheological fluid to achieve the contraction or release action of the artificial muscle until the actual output is consistent with the target signal;

[0041] Step S6: When the artificial muscle needs to maintain a fixed state, the input current of the magnetorheological valve group is cut off, and the yield stress of the magnetorheological fluid is used to maintain locking, thereby reducing system energy consumption.

[0042] The step S4 is specifically as follows:

[0043] a. Dynamically change the intensity of the magnetic field:

[0044] The intensity adjustment of the magnetic field is based on Maxwell's equations and the constitutive model of the magnetorheological fluid:

[0045] When there is no external magnetic field, the shear stress of the magnetorheological fluid satisfies:

[0046] τ MRF =η*γ

[0047] Among them, τ MRF is the shear stress of the magnetorheological fluid, η is the dynamic viscosity of the magnetorheological fluid, and γ is the shear strain of the magnetorheological fluid;

[0048] When an external magnetic field is applied, the magnetorheological fluid is regarded as a Bingham fluid, and its constitutive model is:

[0049]

[0050] Where τ0 is the static yield stress of the magnetorheological fluid, H is the strength of the external magnetic field;

[0051] b. Control the driving force of the magnetorheological fluid between the storage cavity and the driving flexible driving cavity:

[0052] The driving force calculation of the electromagnetic control system is based on the equivalent magnetic circuit model:

[0053]

[0054] Among them, N e is the number of coil turns, I1 is the coil current, G i is the air gap permeance, and the relative displacement is x; from this, the magnitude of the control force on the magnetorheological fluid is obtained.

[0055] In step S5, the deformation control of the driving cavity is achieved by one of the following methods:

[0056] Method A: Deformation control of flexible artificial muscle controlled by inlet magnetorheological valve;

[0057] Step 1-1: The contraction action is initiated, the control unit receives the contraction instruction, and generates a target cavity pressure signal; the input current of the inlet magnetorheological valve is reduced, the magnetic field strength is reduced, and the fluid resistance is reduced;

[0058] Step 1-2: The magnetorheological fluid flows from the storage chamber into the flexible drive chamber through the inlet valve, and the pressure in the flexible drive chamber increases. The wrinkled structure on the inner wall of the silicone rubber chamber expands under the pressure, and the drive chamber contracts axially.

[0059] Steps 1-3: The flexible fiber force sensor monitors the contraction force in real time and feeds it back to the control unit. The current duty cycle is adjusted based on the PID algorithm to accurately control the opening of the inlet valve.

[0060] Steps 1-4: When the target contraction force is reached, the magnetic field strength is increased, the inlet valve is closed, and the cavity pressure is maintained according to the yield stress of the magnetorheological fluid;

[0061] Method B: integrated valve control;

[0062] Step 2-1: The magnetorheological valve is directly integrated into the rigid connection of the flexible drive cavity; the control unit generates differentiated drive signals for the local area according to the target action;

[0063] Step 2-2: The electromagnetic coil adjusts the magnetic field strength through a high-frequency PWM signal; the narrow slit design of the magnetorheological fluid flow channel ensures uniform resistance distribution;

[0064] Step 2-3: Suppress the influence of external vibration on the valve group through anti-interference connectors; monitor the drive cavity shape in real time, and adjust the current parameters through closed-loop feedback;

[0065] Steps 2-4: Simulate the local contraction and extension of natural muscles by independently controlling the valve groups in different areas;

[0066] Method C: Deformation control of distributed valve-controlled multi-cavity flexible artificial muscle;

[0067] Step 3-1: The control unit analyzes the motion command and allocates the target flow rate of each parallel flexible drive cavity;

[0068] Step 2: Each magnetorheological valve is controlled individually, and the flow rate of each cavity is adjusted by differential current;

[0069] Step 3: Achieve bending, twisting or wavy motion by coordinating the filling rate and pressure of each cavity;

[0070] Step 4: Use sensor data to calibrate the pressure difference of each cavity in real time to ensure smooth movement; optimize the stability of the multi-valve group coordinated control through the PID algorithm.

[0071] Method D: Deformation control of cross-type bidirectional tension-compression magnetorheological valve-controlled flexible artificial muscle;

[0072] Step 4-1: The control unit receives the stretching or compression instruction and generates the cross valve opening and closing logic;

[0073] Step 4-2: fluid path switching;

[0074] Stretching mode: the second and fourth magnetorheological valves are closed, and the first and third magnetorheological valves are opened. The magnetorheological fluid flows back to the storage chamber from the first and third magnetorheological valves, the channel pressure decreases, and the artificial muscle stretches.

[0075] Compression mode: close the first and third magnetorheological valves, open the second and fourth magnetorheological valves, the magnetorheological fluid flows in the opposite direction, the flexible drive cavity is filled with fluid and pressurized, and the artificial muscle is compressed;

[0076] Step 4-3: Control the tension / compression rate and output force by adjusting the opening ratio of the cross valve; calculate the driving force based on the equivalent magnetic circuit model to obtain the magnitude of the control force for the magnetorheological fluid;

[0077] Step 4-4: Use the static yield stress of the magnetorheological fluid to lock the cross valve and maintain the stability of the bidirectional action.

[0078] The present invention has the following beneficial effects and advantages:

[0079] 1. The drive system of the present invention has high control accuracy: the magnetorheological valve is used to precisely adjust the working fluid, which can achieve high-precision control of the contraction speed and output force of the flexible actuator, significantly improving the dynamic response quality and stability of the system;

[0080] 2. The actuator of this invention has a fast response speed: The magnetorheological fluid can respond to changes in the external magnetic field in milliseconds, driving the valve body to achieve rapid opening and closing. Compared with traditional pneumatic and hydraulic control systems, the response speed is significantly improved, making it suitable for high-frequency dynamic control scenarios.

[0081] 3. The present invention has a compact structure: the magnetorheological valve is only arranged at the key nodes of the drive pipeline, the overall structure is simple, and few auxiliary equipment are required, which facilitates integration and application in flexible robotic systems with limited volume;

[0082] 4. The present invention has high energy efficiency: the magnetorheological valve requires essentially no continuous energy input when maintaining a static locked state, significantly reducing system energy consumption and improving overall energy utilization, making it suitable for low-power operation requirements.

[0083] 5. The system of the present invention is highly safe: the drive device has natural flexibility, which can provide a soft response in the event of external collisions or environmental interference, reducing potential damage to the surrounding environment or human body, and improving the interactive safety of the system;

[0084] 6. The control strategy of the present invention is flexible: the magnetorheological drive system supports multiple control modes. By adjusting the magnetic field strength and response curve, multi-mode fusion control such as speed control, force control and position control can be achieved to meet different task requirements. BRIEF DESCRIPTION OF THE DRAWINGS

[0085] Figure 1 An equivalent magnetic circuit diagram of the magnetic circuit model of the present invention;

[0086] Figure 2 Flowchart of the system control method of the present invention;

[0087] Figure 3 System structure equivalent diagram of embodiment 1 of the present invention;

[0088] Figure 4 Flowchart of the system control method of Example 1 of the present invention;

[0089] Figure 5 An equivalent cross-sectional view of the magnetorheological valve assembly of the present invention;

[0090] Figure 6 System structure equivalent diagram of embodiment 2 of the present invention;

[0091] Figure 7 System structure equivalent diagram of embodiment 3 of the present invention;

[0092] Figure 8 Flowchart of the system control method of embodiment 3 of the present invention;

[0093] Figure 9 System structure equivalent diagram of embodiment 4 of the present invention;

[0094] Figure 10 Flowchart of the system control method of Example 4 of the present invention;

[0095] Figure 11 System structure equivalent diagram of Example 5 of the present invention;

[0096] Among them, 1-1 is the flexible driving cavity, 1-2 is the magnetorheological valve group, 1-3 is the hydraulic pump, 1-4 is the electromagnetic control system, 1-5 is the control unit, 1-6 is the fluid circulation channel, 2-1 is the valve body, 2-2 is the magnetorheological fluid flow channel, 2-3 is the electromagnetic coil, and 2-4 is the storage cavity. DETAILED DESCRIPTION

[0097] The present invention will be further described in detail below with reference to the accompanying drawings and embodiments.

[0098] The present invention discloses an electromagnetic rheological hydraulic flexible artificial muscle system and control method, which aims to address the problems of existing artificial muscles in terms of single response and insufficient flexibility in terms of drive and control. The system comprises: a flexible drive cavity 1-1, a magnetorheological valve assembly 1-2, a hydraulic pump 1-3, an electromagnetic control system 1-4, a control unit 1-5, and a fluid circulation channel 1-6.

[0099] Flexible drive cavity 1-1 is made of silicone rubber, with a special corrugated structure on its inner wall, which allows it to contract axially under pressure. Rigid joints connect the cavity to the outside at both ends, and the entire cavity adopts a McKibben muscle configuration. Flexible fiber force sensors are installed on the inner surface fibers to measure the real-time status of the flexible drive cavity.

[0100] The output end of the flexible drive cavity 1-1 is connected to the output end of the magnetorheological valve group 1-2 through the fluid circulation channel 1-6, so as to produce axial contraction under the action of pressure and drive the fluid to flow into the drive cavity; the input end of the flexible drive cavity 1-1 is connected to the oil storage tank;

[0101] The input end of the hydraulic pump 1-3 is connected to the oil reservoir, and the output end is connected to the input end of the magnetorheological valve group 1-2;

[0102] The magnetorheological valve assembly 1-2 is configured to adjust the flow resistance of the magnetorheological fluid through a magnetic field; the magnetorheological fluid is contained in a cavity of the magnetorheological valve assembly 1-2; the magnetorheological valve assembly 1-2 is connected to the electromagnetic control system 1-4 to generate a magnetic field acting on the magnetorheological fluid;

[0103] The electromagnetic control system 1-4 is connected to the magnetorheological valve group 1-2 and is used for the constitutive model based on Maxwell's equations and magnetorheological fluid to control the magnetic field strength by adjusting the duty cycle of the input current;

[0104] The control unit 1-5 is used to receive status signals and generate control instructions to achieve the contraction and release of the driving cavity.

[0105] During operation, to achieve the contraction of the artificial muscle, the magnetic field strength of MR valves 1-2 is adjusted to control the flow of MR fluid from the storage chamber into the drive chamber, increasing the pressure in the drive chamber, generating a contraction force and inducing structural deformation. To achieve the relaxation of the artificial muscle, the magnetic field is adjusted to close MR valves 1-2, allowing the existing MR fluid to flow from the drive chamber to the storage chamber, releasing the chamber pressure and resetting the muscle. The MR valves only regulate flow in the system and do not directly affect stiffness. The stiffness of the artificial muscle is primarily determined by changes in pressure within the chamber and the structural parameters of the drive mechanism.

[0106] like Figure 2 FIG. 1 is a flow chart of the system control method of the present invention. The control method of the electrically controlled magnetorheological hydraulic flexible artificial muscle system of the present invention comprises the following steps:

[0107] Step S1: receiving an external input desired contraction force or displacement signal and generating a corresponding control target;

[0108] Step S2: obtaining pressure, deformation and position data of the flexible driving cavity 1-1 through sensors, and providing real-time feedback of the output state of the artificial muscle through flexible fiber force sensors;

[0109] Step S3: Based on the PID algorithm and the feedback control model, combined with the difference between the sensor data and the target signal, the input current adjustment amount of the electromagnetic control system 1-4 is calculated;

[0110] Step S4: adjusting the current duty cycle input to the magnetorheological valve assembly 1-2 through the electromagnetic control system 1-4, dynamically changing the intensity of the magnetic field, and controlling the driving force of the magnetorheological fluid between the storage chamber 2-4 and the driving flexible driving chamber 1-1;

[0111] Step S5: adjusting the cavity pressure of the flexible driving cavity 1-1 by changing the flow rate of the magnetorheological fluid to achieve the contraction or release action of the artificial muscle until the actual output is consistent with the target signal;

[0112] Step S6: When the artificial muscle needs to be kept in a fixed state, the input current of the magnetorheological valve group 1-2 is cut off, and the yield stress of the magnetorheological fluid is used to maintain locking, thereby reducing system energy consumption.

[0113] 1) Magnetorheological valve group:

[0114] Among them, the magnetorheological valve group 1-2 is located at the fluid inlet and / or outlet, and is used to control the flow of fluid in the system, including: a valve body 2-1, a magnetorheological fluid flow channel 2-2, an electromagnetic coil 2-3 and a storage chamber 2-4;

[0115] Magnetorheological valve assembly 1-2 contains magnetorheological fluid encapsulated within a valve body. The valve body utilizes a high-precision multi-cavity structure, and the magnetorheological fluid flow channel is specially designed as a channel with uniform slits. A high-performance electromagnetic coil is positioned around the inner side of the valve body, and electromagnetic coil 2-3 is signal-linked to the system control unit. When control unit 1-5 is energized, electromagnetic coil 2-3 generates a magnetic field, and the magnetic flux is completely closed through a magnetic circuit with low magnetic resistance. Under the influence of the magnetic field, the viscosity of the fluid within the magnetorheological fluid flow channel 2-2 increases rapidly, forming a dynamically adjustable resistance distribution. By precisely adjusting the input current, magnetorheological valve assembly 1-2 achieves real-time, stepless control of the fluid flow within the system, thereby meeting the complex fluid execution requirements of the robot in multiple states and improving the system's response speed and control accuracy.

[0116] 2) Electromagnetic control system:

[0117] The magnetorheological system of the present invention calculates an alternating electromagnetic field by computationally solving Maxwell's equations. The force exerted by the energized coil on the magnetorheological fluid, combined with a magnetorheological constitutive model and a constructed magnetic circuit model, is calculated and used as the driving force for the entire system. Maxwell's equations consist of four equations describing the interaction and propagation of magnetic and electric fields: Gauss's law, which describes how electric charges generate electric fields; Gauss's magnetic law, which explains the nonexistence of magnetic monopoles; Faraday's law of induction, which describes how time-varying magnetic fields generate electric fields; and Ampere's circuit law, which describes how current and time-varying electric fields generate magnetic fields.

[0118] When there is no external magnetic field, the constitutive model of magnetorheological fluid is:

[0119] τ MRF =η*γ

[0120] Among them, τ MRF is the shear stress of the magnetorheological fluid, η is the dynamic viscosity of the magnetorheological fluid, and γ is the shear strain of the magnetorheological fluid;

[0121] After applying an external magnetic field, the magnetorheological fluid described in this paper is regarded as a Bingham fluid, and its constitutive model is calculated as follows:

[0122]

[0123] Where τ0 is the static yield stress of the magnetorheological fluid, H is the strength of the external magnetic field

[0124] A magnetic circuit model is established for the magnetorheological fluid mentioned in the present invention. The magnetic field passes through the coil, the iron core, the air gap (MRF) and then returns to the coil. Its equivalent magnetic circuit is as follows: Figure 1 shown.

[0125] Combined with Maxwell's equations, it can be obtained that when an external magnetic field acts on the magnetic fluid, the driving force of the magnetic fluid is:

[0126]

[0127] where N e is the number of coil turns, I1 is the coil current, G i is the air gap permeance, and the relative displacement is x. From this, we can derive the magnitude of the control force for the magnetorheological fluid.

[0128] 3) Control unit:

[0129] It includes: a microcontroller and a pressure sensor and a position sensor connected thereto;

[0130] The pressure sensor is installed inside the flexible driving cavity 1-1, at the input end or output end of the guide pipe or the magnetorheological valve group 1-2, and is used to monitor the hydraulic pressure changes of the driving cavity in real time;

[0131] Position sensors are integrated into the rigid joints at both ends of the flexible drive cavity 1-1, the inner wall wrinkle structure area or the external load connection point, and the deformation or displacement is detected by the flexible fiber force sensor;

[0132] Among them, the pressure sensor works based on the piezoresistive effect or piezoelectric effect, the position sensor works based on the strain effect or capacitance change, and the sensor signal is input into the microcontroller after analog-to-digital conversion to form a closed-loop feedback control.

[0133] The present invention mentions an artificial muscle closed-loop feedback control system based on magnetorheological valve control. The system flow chart is as follows Figure 2As shown. The system consists of multiple modules, in which the control target is first generated through user input or desired force. The microcontroller receives the input signal and calculates the control signal for driving the electromagnetic coil according to the preset algorithm. These signals are transmitted to the magnetorheological valve group 1-2 through the driver / amplifier. The magnetorheological valve group 1-2 uses the electromagnetic field to regulate the flow of the fluid, thereby controlling the movement of the hydraulic or pneumatic actuator and driving the artificial muscle to complete the target action. In order to ensure the high precision and stability of the system, the output state of the artificial muscle is monitored in real time by the flexible fiber force sensor inside the artificial muscle, and the feedback signal is returned to the controller to form a closed-loop control structure. The existence of the feedback path enables the system to adjust according to the difference between the actual output and the desired target, thereby optimizing the response of the actuator and enhancing the stability and precision of the system. The design of the entire system reflects the advantages of dynamic control based on the characteristics of magnetorheological fluid, especially in force regulation and precision control.

[0134] 4) Highly efficient magnetorheological fluid components:

[0135] The high-efficiency magnetorheological fluid described in the present invention consists of dispersed phase particles, a carrier fluid, and additives. The dispersed phase particles are composite soft magnetic particles prepared by using metal particles to coat soft magnetic particles with carbonyl iron powder. Specifically, a nanoshell coating method is used, in which nano-oxides (such as SiO2 and Al2O3) are used to form a shell on the surface of the magnetic particles. By regulating the thickness and structure of the shell, the stability and rheological properties of the magnetorheological fluid are improved. At the same time, polysiloxane is used as the carrier fluid, and no sedimentation occurs after standing for 365 days, demonstrating excellent sedimentation stability. To further enhance its performance, silica nanoparticles are added to the carrier fluid to further improve the stability and mechanical properties of the magnetorheological fluid. These nanoparticles can form a composite structure with the magnetic particles, enhancing the interaction between the particles, thereby improving the yield stress and anti-settling properties of the magnetorheological fluid. Subsequently, a dispersant, glycerol monooleate, an anti-settling agent, an organometallic silicon copolymer, and an anti-wear agent, a phosphate ester, are added to improve the sedimentation stability, redispersibility, zero-field viscosity, and shear yield strength of the MRF. Finally, the surfactant iodinated aromatic polymer sulfonated polystyrene was added. Studies have shown that these polymers have good dispersibility and stability and can effectively prevent the aggregation and sedimentation of magnetic particles.

[0136] Example 1: Inlet magnetorheological valve controlled flexible artificial muscle

[0137] like Figure 3 As shown, the magnetorheological valve-controlled flexible artificial muscle of this embodiment includes: a flexible driving cavity 1-1, a magnetorheological valve group 1-2, a hydraulic pump 1-3, an electromagnetic control system 1-4, a control unit 1-5 and a fluid circulation channel 1-6.

[0138] In this embodiment, the magnetorheological valve group 1-2 is provided with one, and the specific structure is as follows Figure 5 As shown, the valve body 2-1, located along the fluid flow path from the storage chamber to the drive chamber, primarily comprises a valve body 2-1, a magnetorheological fluid channel 2-2, an electromagnetic coil 2-3, and a storage chamber 2-4. The magnetorheological fluid channel 2-2 utilizes a specially designed slit structure, attached to the inner wall of the valve body 2-1. The slit width ranges from 0.01 to 5 mm, ensuring uniform resistance distribution under the influence of the magnetic field.

[0139] A storage chamber 2-4 is provided in the valve body 2-1, and magnetorheological fluid is contained in the storage chamber 2-4. The input end of the storage chamber 2-4 is connected to the hydraulic pump 1-3, and the output end is connected to the flexible drive chamber 1-1 through the fluid circulation channel 1-6; the electromagnetic coil 2-3 is arranged around the inner side of the valve body 2-1 and is connected to the electromagnetic control system 1-4, forming an inlet magnetorheological valve-controlled flexible artificial muscle.

[0140] The magnetorheological fluid uses a commercial formula of carbon iron particles suspended in silicone oil with a particle concentration of 30%. The dynamic yield stress can reach 80kPa under the action of a magnetic field.

[0141] The electromagnetic control system 1-4 includes a drive circuit and control algorithm, providing an adjustable current in the range of 0-2A to generate a magnetic field acting on the magnetorheological valve. The system uses PWM control to reduce energy consumption. The control unit 1-5 monitors the state of the artificial muscle in real time and executes the control algorithm. The control algorithm combines PID and feedback control to achieve precise flow control.

[0142] During operation, when the artificial muscle needs to contract, the control unit 1-5 sends a signal to the electromagnetic control system 1-4 to reduce the magnetic field strength of the inlet magnetorheological valve group 1-2, reduce the valve resistance, and allow the working fluid to flow from the storage chamber into the drive chamber, causing the drive chamber to expand and generate axial contraction force; when the artificial muscle needs to maintain a specific state, an appropriate magnetic field is applied to make the magnetorheological valve group 1-2 generate sufficient resistance to prevent the fluid flow; when the artificial muscle needs to relax, the fluid is pressed back into the storage chamber through the one-way valve by relying on an external load or auxiliary mechanism.

[0143] The system control flow chart of Example 1 is as follows Figure 4 As shown, the following steps are included:

[0144] Step 1-1: The contraction action is started, the control unit 1-5 receives the contraction instruction and generates a target cavity pressure signal; the input current of the inlet magnetorheological valve 1-2 is reduced, the magnetic field strength is reduced, and the fluid resistance is reduced;

[0145] Step 1-2: The magnetorheological fluid flows from the storage chamber 2-4 into the flexible driving chamber 1-1 through the inlet valve, and the pressure in the flexible driving chamber 1-1 increases; the wrinkled structure on the inner wall of the silicone rubber chamber expands under the pressure, and the driving chamber contracts axially;

[0146] Steps 1-3: The flexible fiber force sensor monitors the contraction force in real time and feeds it back to the control unit. The current duty cycle is adjusted based on the PID algorithm to accurately control the opening of the inlet valve.

[0147] Steps 1-4: When the target contraction force is reached, the magnetic field strength is increased, the inlet valve is closed, and the cavity pressure is maintained according to the yield stress of the magnetorheological fluid;

[0148] The artificial muscle of this embodiment can achieve a contraction force range of 0-100N, a valve response time of less than 10ms, and a flow control accuracy of up to ±2%.

[0149] Example 2: Integrated magnetorheological valve-controlled flexible artificial muscle

[0150] like Figure 6 As shown, this embodiment builds on the overall structure of Example 1 by installing external magnetorheological valve groups 1-2 at the rigid connections of the artificial muscle, forming an integrated structure with the artificial muscle. This integrated design not only effectively reduces system volume and connection complexity, but also improves response speed and control accuracy. The rapid response characteristics of the magnetorheological valve enable it to adjust fluid flow in real time according to control commands, thereby precisely controlling the contraction and extension behavior of the artificial muscle. The specific control process is as follows:

[0151] Step 2-1: The magnetorheological valve 1-2 is directly integrated into the rigid connection of the flexible driving cavity 1-1; the control unit 1-5 generates a differentiated driving signal for the local area according to the target action;

[0152] Step 2-2: The electromagnetic coil 2-3 adjusts the magnetic field strength through a high-frequency PWM signal; the slit design of the magnetorheological fluid flow channel 2-2 ensures uniform resistance distribution;

[0153] Step 2-3: Suppress the influence of external vibration on the valve group through anti-interference connectors; monitor the drive cavity shape in real time, and adjust the current parameters through closed-loop feedback;

[0154] Steps 2-4: Simulate the local contraction and extension of natural muscles by independently controlling the valve groups in different areas;

[0155] Furthermore, the compact layout of the MR valve assembly 1-2 significantly reduces the impact of external disturbances on system performance, enhancing the overall structural stability and anti-interference capabilities. Independent control of the MR valves at each joint enables differentiated actuation of localized muscle regions, effectively simulating the mechanical response patterns of natural muscle under varying motion conditions.

[0156] This implementation is particularly suitable for application scenarios with high requirements on response speed, spatial layout and control accuracy, such as bionic robots with humanoid structures, flexible wearable devices or intelligent mechanical end effectors with complex grasping capabilities.

[0157] Example 3: Distributed Valve-Controlled Multi-Cavity Flexible Artificial Muscle

[0158] like Figure 7 As shown, this embodiment is based on the embodiment 1, and each storage cavity 2-4 is arranged in parallel, and the input end of each storage cavity 2-4 is connected to the hydraulic pump 1-3, and the output end is connected to a corresponding flexible driving cavity 1-1; forming a parallel design of multiple flexible driving cavities 1-1;

[0159] This embodiment achieves complex motion patterns and force output characteristics by controlling the fluid inflow and outflow rates of different cavities. The flow chart of the system control method of this embodiment is as follows: Figure 8 As shown, the following steps are included:

[0160] Step 3-1: The control unit 1-5 analyzes the motion instruction and allocates the target flow rate to each parallel flexible drive cavity 1-1;

[0161] Step 2: Each magnetorheological valve group 1-2 is controlled individually to adjust the flow rate of each cavity through differentiated current;

[0162] Step 3: Achieve bending, twisting or wavy motion by coordinating the filling rate and pressure of each cavity;

[0163] Step 4: Use sensor data to calibrate the pressure difference of each cavity in real time to ensure smooth movement; optimize the stability of the multi-valve group coordinated control through the PID algorithm.

[0164] The inlet or outlet MR valves of each cavity can be controlled individually, making the system highly flexible and adaptable. By coordinating the valve openings of different cavities, a coordinated movement effect similar to that of biological muscle groups can be achieved.

[0165] This design is particularly suitable for complex motion control and morphological change applications, such as the swimming control of bionic robotic fish and the precise operation of flexible robotic arms.

[0166] Example 4: Cross-type bidirectional tension-compression magnetorheological valve-controlled flexible artificial muscle

[0167] like Figure 9As shown, in this embodiment, based on embodiment 1, the storage chambers 2-4 of the four magnetorheological valve groups 1-2 are cross-connected in parallel to form a cross-cross arrangement; when the artificial muscle needs to be stretched, the second magnetorheological valve and the fourth magnetorheological valve are closed, the first magnetorheological valve and the third magnetorheological valve are connected, and the fluid circulates to the oil storage tank through the fluid circulation channels 1-6, thereby achieving the stretching of the artificial muscle; when the artificial muscle needs to be compressed, the first magnetorheological valve and the third magnetorheological valve are closed, the second magnetorheological valve and the fourth magnetorheological valve are opened, and the fluid circulates to the oil storage tank through the fluid circulation channels 1-6; the system control method flow chart of embodiment 4 is shown in FIG. Figure 10 As shown, the following steps are included:

[0168] Step 4-1: The control unit 1-5 receives the stretching or compression instruction and generates the cross valve opening and closing logic;

[0169] Step 4-2: fluid path switching;

[0170] Stretching mode: the second and fourth magnetorheological valves are closed, and the first and third magnetorheological valves are opened. The magnetorheological fluid flows from the first and third magnetorheological valves back to the storage chambers 2-4, the channel pressure decreases, and the artificial muscle stretches.

[0171] Compression mode: the first and third magnetorheological valves are closed, the second and fourth magnetorheological valves are opened, the magnetorheological fluid flows in the opposite direction, the flexible drive cavity 1-1 is filled with fluid and pressurized, and the artificial muscle is compressed;

[0172] Step 4-3: Control the tension / compression rate and output force by adjusting the opening ratio of the cross valve; calculate the driving force based on the equivalent magnetic circuit model to obtain the magnitude of the control force for the magnetorheological fluid;

[0173] Step 4-4: Use the static yield stress of the magnetorheological fluid to lock the cross valve and maintain the stability of the bidirectional action.

[0174] The cross-parallel structure enables precise control of contraction and relaxation, improving system responsiveness and control accuracy. Simultaneous opening and closing of opposite cross valves primarily controls the flow rate and speed of fluid filling, influencing the contraction and relaxation rates of the muscles. The four valves can work together to achieve more complex motion control.

[0175] This embodiment is particularly suitable for application scenarios that require precise control of the contraction and relaxation processes, such as bionic robotic arms and precision manipulation tasks.

[0176] Example 5: Electric-controlled magnetorheological hydraulic flexible artificial muscle system driving connecting rod mechanism

[0177] like Figure 11As shown, this embodiment proposes an electrically controlled magnetorheological hydraulic flexible artificial muscle system. When used as a linear actuator, one end of the system is fixed and the flow state of the magnetorheological fluid is controlled to achieve the extension or contraction movement of the flexible artificial muscle, thereby driving the connecting rod structure connected in series with the system to produce linear displacement, and finally driving the crank mechanism at the far end to rotate.

[0178] This embodiment can achieve flexible adjustment of linear drive motion through precise control of the artificial muscle system. It is suitable for various mechanical structures that require precise displacement output and has advantages such as fast response, compact structure, and strong adaptability. The specific working method of the system is shown in the figure and includes the following steps:

[0179] Step 1: The control unit issues a displacement or rotation angle command and resolves it into the target displacement;

[0180] Step 2: The electrically controlled magnetorheological valve regulates the flow of fluid according to the target displacement, controlling the contraction or extension rate of the artificial muscle.

[0181] Step 3: The length change of the artificial muscle is transmitted to the distal crank through the connecting rod structure to achieve the desired rotation angle;

[0182] Step 4: The current system status is fed back through the displacement sensor or pressure sensor, and the control unit corrects the control parameters in real time to achieve closed-loop control;

[0183] Step 5: Use PID or adaptive algorithm to optimize system stability and response speed.

[0184] The system has a simple structure and precise control, and is particularly suitable for scenarios where space is limited but reliable linear drive is required, such as micro-robotic arm joints, bionic robot joints and other application fields.

[0185] In summary, the present invention has a simple structure and a fast control response. Combined with Examples 1 to 5, the present invention is not limited to the application fields of the five embodiments. The present invention is suitable for bionic muscle systems that require active drive and adjustable compliance, and has broad application prospects in the fields of intelligent prostheses, rehabilitation equipment, micro robots, and humanoid dexterous hands.

[0186] Those skilled in the art will understand that the above description is only a preferred embodiment of the present invention, and the features described in the various embodiments and / or claims of the present disclosure may be combined or coupled in various ways, even if such a combination or coupling is not explicitly described in the present disclosure. It is not intended to limit the present invention. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art may still modify the technical solutions described in the aforementioned embodiments or make equivalent substitutions for some of the technical features therein. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention shall be included in the scope of protection of the present invention.

[0187] Although preferred embodiments of the present invention have been described, those skilled in the art may make additional changes and modifications to these embodiments once they are aware of the basic inventive concepts. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments and all changes and modifications that fall within the scope of the present invention. Obviously, those skilled in the art may make various changes and modifications to the present invention without departing from the spirit and scope of the present invention. Thus, the present invention is intended to include such changes and modifications as fall within the scope of the claims and their equivalents.

Claims

1. An electrically controlled magnetorheological hydraulic flexible artificial muscle system, characterized in that: include: A flexible driving cavity (1-1), a magnetorheological valve group (1-2), a hydraulic pump (1-3), an electromagnetic control system (1-4), a control unit (1-5) and a fluid circulation channel (1-6); The flexible driving cavity (1-1) has a cavity configuration of McKibben muscle bionic design, is made of silicone rubber, has an inner wall fold structure of axial corrugation, is connected to the outside through rigid joints at both ends, and is integrated with a fiber force sensor to monitor the cavity state in real time; The output end of the flexible drive cavity (1-1) is connected to the output end of the magnetorheological valve group (1-2) through a fluid circulation channel (1-6) to generate axial contraction under pressure to drive the fluid to flow into the drive cavity; the input end of the flexible drive cavity (1-1) is connected to an oil storage tank; The input end of the hydraulic pump (1-3) is connected to the oil storage tank, and the output end is connected to the input end of the magnetorheological valve group (1-2); The magnetorheological valve assembly (1-2) is used to adjust the flow resistance of the magnetorheological fluid through a magnetic field; the magnetorheological fluid is contained in a cavity of the magnetorheological valve assembly (1-2); the magnetorheological valve assembly (1-2) is connected to an electromagnetic control system (1-4) to generate a magnetic field acting on the magnetorheological fluid; The electromagnetic control system (1-4) is connected to the magnetorheological valve group (1-2) and is used for the constitutive model based on Maxwell's equations and magnetorheological fluid to control the magnetic field intensity by adjusting the duty cycle of the input current; The control unit (1-5) is used to receive status signals and generate control instructions to achieve the contraction and release of the drive cavity.

2. The electrically controlled magnetorheological hydraulic flexible artificial muscle system according to claim 1, characterized in that: The magnetorheological valve assembly (1-2) is provided with one, comprising: a valve body (2-1), a magnetorheological fluid flow channel (2-2), an electromagnetic coil (2-3) and a storage chamber (2-4); The magnetorheological fluid flow channel (2-2) is designed as a channel with a uniform slit, and is attached to the inner wall of the valve body (2-1), and the slit width is 0.01-5 mm; A storage chamber (2-4) is provided in the valve body (2-1), and magnetorheological fluid is contained in the storage chamber (2-4). The input end of the storage chamber (2-4) is connected to the hydraulic pump (1-3), and the output end is connected to the flexible drive chamber (1-1) via a fluid circulation channel (1-6); The electromagnetic coil (2-3) is arranged around the inner side of the valve body (2-1) and is connected to the electromagnetic control system (1-4) to form an inlet magnetorheological valve controlled flexible artificial muscle.

3. The electrically controlled magnetorheological hydraulic flexible artificial muscle system according to claim 2, characterized in that: The magnetorheological valve assembly (1-2) is provided with one, and the external magnetorheological valve is installed at the rigid connection of the artificial muscle to form an integral structure with the artificial muscle, thereby forming an integrated magnetorheological valve-controlled flexible artificial muscle.

4. The electrically controlled magnetorheological hydraulic flexible artificial muscle system according to claim 1, characterized in that: The magnetorheological valve assembly (1-2) is provided in plurality, each comprising: a valve body (2-1), a magnetorheological fluid flow channel (2-2) and an electromagnetic coil (2-3); The magnetorheological fluid flow channel (2-2) is designed as a channel with a uniform slit, and is attached to the inner wall of the valve body (2-1). The slit width is 0.01-5 mm. A storage cavity (2-4) is provided in the valve body (2-1). Each storage cavity (2-4) is arranged in parallel, and the input end of each storage cavity (2-4) is connected to the hydraulic pump (1-3), and the output end is connected to a corresponding flexible driving cavity (1-1); The electromagnetic coil (2-3) is arranged around the inner side of the valve body (2-1) and is connected to the electromagnetic control system (1-4) to form a distributed valve-controlled multi-cavity flexible artificial muscle.

5. The electrically controlled magnetorheological hydraulic flexible artificial muscle system according to claim 1, characterized in that: There are four magnetorheological valve groups (1-2), each comprising: a valve body (2-1), a magnetorheological fluid flow channel (2-2) and an electromagnetic coil (2-3); The magnetorheological fluid flow channel (2-2) is designed as a channel with a uniform slit, and is attached to the inner wall of the valve body (2-1). The slit width is 0.01-5 mm. A storage cavity (2-4) is provided in the valve body (2-1). The storage chambers (2-4) of the four magnetorheological valve groups (1-2) are cross-connected in parallel to form a cross-type arrangement; when the artificial muscle needs to be stretched, the second magnetorheological valve and the fourth magnetorheological valve are closed, the first magnetorheological valve and the third magnetorheological valve are connected, and the fluid circulates to the oil storage tank through the fluid circulation channel (1-6), thereby achieving stretching of the artificial muscle; when the artificial muscle needs to be compressed, the first magnetorheological valve and the third magnetorheological valve are closed, the second magnetorheological valve and the fourth magnetorheological valve are opened, and the fluid circulates to the oil storage tank through the fluid circulation channel (1-6); The electromagnetic coil (2-3) is arranged around the outside of the valve body (2-1) and is connected to the electromagnetic control system (1-4) to form a cross-type bidirectional tension-compression magnetorheological valve-controlled flexible artificial muscle.

6. The electrically controlled magnetorheological hydraulic flexible artificial muscle system according to claim 1, characterized in that: The control unit (1-5) comprises: a microcontroller and a pressure sensor and a position sensor connected thereto; The pressure sensor is installed inside the flexible driving cavity (1-1), at the input end or output end of the guide pipe or the magnetorheological valve group (1-2), and is used to monitor the hydraulic pressure changes of the driving cavity in real time; The position sensor is integrated into the rigid joints at both ends of the flexible driving cavity (1-1), the inner wall wrinkle structure area or the external load connection point, and detects deformation or displacement through a flexible fiber force sensor; The pressure sensor operates based on the piezoresistive effect or the piezoelectric effect, and the position sensor operates based on the strain effect or the capacitance change. The sensor signal is input into the microcontroller after analog-to-digital conversion to form a closed-loop feedback control.

7. The electrically controlled magnetorheological hydraulic flexible artificial muscle system according to claim 1, characterized in that: The magnetorheological fluid is a suspension of carbon iron particles with a particle concentration of 30% and a dynamic yield stress of 80 kPa; A carbon iron particle suspension comprising dispersed phase particles, a carrier liquid and additives; The dispersed phase particles are composite soft magnetic particles whose surface is coated with nano-oxides of SiO2 or Al2O3, with carbonyl iron powder as the matrix, and the nano-shell coating technology is used to enhance the oxidation resistance and dispersibility of the particles. The carrier liquid is based on polysiloxane and is fine and has no sedimentation; The additives include silica nanoparticles, a dispersant, an anti-settling agent, an anti-wear agent, and a surfactant added in sequence to improve the sedimentation stability, redispersibility, zero-field viscosity, and shear yield strength of the MRF.

8. The control method of an electrically controlled magnetorheological hydraulic flexible artificial muscle system according to claim 1, characterized in that: The following steps are involved: Step S1: receiving an external input desired contraction force or displacement signal and generating a corresponding control target; Step S2: obtaining pressure, deformation and position data of the driving flexible driving cavity (1-1) through sensors, and providing real-time feedback of the output state of the artificial muscle through flexible fiber force sensors; Step S3: Based on the PID algorithm and the feedback control model, combined with the difference between the sensor data and the target signal, the input current adjustment amount of the electromagnetic control system (1-4) is calculated; Step S4: adjusting the duty cycle of the current input to the magnetorheological valve group (1-2) through the electromagnetic control system (1-4), dynamically changing the intensity of the magnetic field, and controlling the driving force of the magnetorheological fluid between the storage cavity (2-4) and the driving flexible driving cavity (1-1); Step S5: adjusting the cavity pressure of the flexible driving cavity (1-1) by changing the flow rate of the magnetorheological fluid to achieve the contraction or release action of the artificial muscle until the actual output is consistent with the target signal; Step S6: When the artificial muscle needs to maintain a fixed state, the input current of the magnetorheological valve group (1-2) is cut off, and the yield stress of the magnetorheological fluid is used to maintain locking, thereby reducing system energy consumption.

9. The control method of the electrically controlled magnetorheological hydraulic flexible artificial muscle system according to claim 8, characterized in that: The step S4 is specifically as follows: a. Dynamically change the intensity of the magnetic field: The intensity adjustment of the magnetic field is based on Maxwell's equations and the constitutive model of the magnetorheological fluid: When there is no external magnetic field, the shear stress of the magnetorheological fluid satisfies: t MRF =η*γ Among them, τ MRF is the shear stress of the magnetorheological fluid, η is the dynamic viscosity of the magnetorheological fluid, and γ is the shear strain of the magnetorheological fluid; When an external magnetic field is applied, the magnetorheological fluid is regarded as a Bingham fluid, and its constitutive model is: Where τ0 is the static yield stress of the magnetorheological fluid, H is the strength of the external magnetic field; b. Controlling the driving force of the magnetorheological fluid in the storage chamber (2-4) and the flexible driving chamber (1-1): The driving force calculation of the electromagnetic control system (1-4) is based on the equivalent magnetic circuit model: Among them, N e is the number of coil turns, I1 is the coil current, G i is the air gap permeance, and the relative displacement is x; from this, the magnitude of the control force on the magnetorheological fluid is obtained.

10. The control method of the electrically controlled magnetorheological hydraulic flexible artificial muscle system according to claim 8, characterized in that: In step S5, the deformation control of the driving cavity is achieved by one of the following methods: Method A: Deformation control of flexible artificial muscle controlled by inlet magnetorheological valve; Step 1-1: The contraction action is started, and the control unit (1-5) receives the contraction instruction and generates a target cavity pressure signal; Reduce the input current of the inlet magnetorheological valve (1-2), reduce the magnetic field strength, and reduce the fluid resistance; Step 1-2: The magnetorheological fluid flows from the storage chamber (2-4) into the flexible driving chamber (1-1) through the inlet valve, and the chamber pressure of the flexible driving chamber (1-1) increases; the wrinkled structure of the inner wall of the silicone rubber chamber expands under the action of the pressure, and the driving chamber contracts axially; Steps 1-3: The flexible fiber force sensor monitors the contraction force in real time and feeds it back to the control unit. The current duty cycle is adjusted based on the PID algorithm to accurately control the opening of the inlet valve. Steps 1-4: When the target contraction force is reached, the magnetic field strength is increased, the inlet valve is closed, and the cavity pressure is maintained according to the yield stress of the magnetorheological fluid; Method B: integrated valve control; Step 2-1: The magnetorheological valve (1-2) is directly integrated into the rigid connection of the flexible driving cavity (1-1); the control unit (1-5) generates a differentiated driving signal for a local area according to the target action; Step 2-2: The electromagnetic coil (2-3) adjusts the magnetic field strength through a high-frequency PWM signal; the slit design of the magnetorheological fluid flow channel (2-2) ensures uniform resistance distribution; Step 2-3: Suppress the influence of external vibration on the valve group through anti-interference connectors; monitor the drive cavity shape in real time, and adjust the current parameters through closed-loop feedback; Steps 2-4: Simulate the local contraction and extension of natural muscles by independently controlling the valve groups in different areas; Method C: Deformation control of distributed valve-controlled multi-cavity flexible artificial muscle; Step 3-1: The control unit (1-5) analyzes the motion instruction and allocates the target flow rate of each parallel flexible drive cavity (1-1); Step 2: Each magnetorheological valve (1-2) is controlled individually to adjust the flow rate of each cavity by differential current; Step 3: Achieve bending, twisting or wavy motion by coordinating the filling rate and pressure of each cavity; Step 4: Use sensor data to calibrate the pressure difference of each cavity in real time to ensure smooth movement; optimize the stability of the multi-valve group coordinated control through the PID algorithm. Method D: Deformation control of cross-type bidirectional tension-compression magnetorheological valve-controlled flexible artificial muscle; Step 4-1: The control unit (1-5) receives the stretching or compression instruction and generates the cross valve opening and closing logic; Step 4-2: fluid path switching; Stretching mode: the second and fourth magnetorheological valves are closed, and the first and third magnetorheological valves are opened. The magnetorheological fluid flows back to the storage chamber (2-4) from the first and third magnetorheological valves, the channel pressure decreases, and the artificial muscle stretches. Compression mode: the first magnetorheological valve and the third magnetorheological valve are closed, the second magnetorheological valve and the fourth magnetorheological valve are opened, the magnetorheological fluid flows in the reverse direction, the flexible driving cavity (1-1) is filled with liquid and pressurized, and the artificial muscle is compressed; Step 4-3: Control the tension / compression rate and output force by adjusting the opening ratio of the cross valve; calculate the driving force based on the equivalent magnetic circuit model to obtain the magnitude of the control force for the magnetorheological fluid; Step 4-4: Use the static yield stress of the magnetorheological fluid to lock the cross valve and maintain the stability of the bidirectional action.

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