Rod force servo control method and system for inhibiting redundant force of active side rod

Abstract

The invention discloses a rod force servo control method and system for restraining redundant force of an active side rod. The control method comprises the following steps that the deflection angle pushed by the active side rod is obtained; determining an ideal rod force according to the deflection angle; the ideal rod force after softening is determined according to the ideal rod force; the actual rod force of the active side rod is obtained, the actual rod force and the softened ideal rod force are subjected to difference to generate deviation, and a first reference instruction signal is output through rod force closed-loop sliding mode control; a deviation value is generated by subtracting the first reference instruction signal from a feedback rotating speed signal of the motor, and a second reference instruction signal is output through speed closed-loop sliding mode control; inputting a deviation value generated by subtracting the second reference instruction signal from a feedback current signal of the motor into a current controller, and outputting a control signal by the current controller; and converting the control signal into a driving signal of the motor to drive the motor to operate. According to the method, the redundant force phenomenon generated in the active side rod force servo process can be restrained, the man-machine interaction is enhanced, and the driving quality is improved.

Description

Technical Field

[0001] The invention relates to the technical field of aircraft driving, and in particular to a rod force servo control method and system for suppressing redundant force of an active side rod. Background Art

[0002] In order to make more effective use of cockpit resources and improve the pilot's field of vision, advanced civil and military aircraft at home and abroad often use side sticks as cockpit manual control mechanisms, but this type cuts off the mechanical connection between the pilot and the aircraft's control surface, causing the pilot to lose the ability to perceive the aerodynamic characteristics of the control surface. Therefore, traditional side sticks (called passive side sticks) often use spring load mechanisms to simulate the effects and changes of aerodynamic forces, but there are technical problems such as difficulty in accurately simulating the stick force-stick displacement characteristics under multiple configurations of the aircraft, and difficulty in realizing mechanical linkage of the double side sticks due to the small side stick control stroke, which may even affect the aircraft's control safety in complex flight environments.

[0003] In response to the above problems, an active side stick solution has emerged that controls the characteristics of the human sensing system based on aircraft status information. The implementation basis of the active side stick is the servo drive technology of the motor. In the interaction between the human and machine system, the pilot's feeling of force is very natural and rapid. The active side stick servo system is generally implemented based on the traditional expert PID (proportional-integral-derivative control) control method, which has the advantages of simple structure and high reliability.

[0004] However, under high load conditions, due to the inertia of the control mechanism and the time-varying nonlinearity in the system, when the pilot controls the aircraft through the active side stick, the active side stick will be in active mode. In active mode, the active side stick is affected by strong position disturbances, the inertia of the control mechanism and the time-varying nonlinearity in the system. When the control is started, the stick force gradient changes rapidly, and the direction is changed, there will be excess force, which will cause the pilot to shake the stick and hit his hand during the active side stick operation. The excess force phenomenon makes the traditional expert PID servo control system susceptible to parameter changes and external interference, and has weak robustness, making it difficult to meet the requirements of high-precision servo tracking performance under variable load conditions. In order to ensure flight safety, how to solve the problem of eliminating the excess force generated by the active side stick and precise force control, so that the maximum acceptable level of force pulsation at this point is acceptable to the driver is the current technical difficulty. Summary of the invention

[0005] The purpose of the present invention is to provide a stick force servo control method and system for suppressing the redundant force of the active side stick, and to improve the control accuracy of the system by utilizing the closed-loop control of the system, so as to suppress the redundant force phenomenon generated in the process of active side stick force servo, and then provide the pilot with a natural and variable force feedback, so that the pilot can feel the flight state of the aircraft through this force feedback, enhance the human-computer interaction, and improve the driving quality.

[0006] The technical solution of the present invention is:

[0007] A rod force servo control method for suppressing the redundant force of an active side rod comprises the following steps:

[0008] Get the deflection angle of the active side stick push;

[0009] Determine the ideal rod force based on the deflection angle;

[0010] Determine the ideal rod force after softening based on the ideal rod force;

[0011] The actual rod force of the active side rod is obtained, and the actual rod force obtained is subtracted from the ideal rod force after softening, and the deviation value generated by the subtraction is used as the input signal, and the first reference command signal is output through the rod force closed-loop sliding mode control;

[0012] Subtract the output first reference command signal from the feedback motor speed signal, use the difference value generated by the difference as the input signal, and output a second reference command signal through speed closed-loop sliding mode control;

[0013] Subtracting the output second reference command signal from the feedback current signal of the motor, inputting the deviation value generated by the difference into the current controller, and the current controller outputs a control signal;

[0014] The output control signal is converted into a driving signal of the motor, and the motor operates according to the driving signal.

[0015] Preferably, as a further improvement of the present invention, the process of determining the ideal rod force according to the deflection angle is realized by calculating the rod force-rod displacement curve, and the rod force-rod displacement curve is determined by the following formula:

[0016]

[0017] In the formula, F * is the ideal force of the active side stick, and θ is the deflection angle of the active side stick.

[0018] The ideal rod force is softened using the following formula:

[0019]

[0020] Where F1(s) is the Laplace transform of the ideal rod force after softening, F * (s) is the Laplace transform of the ideal force of the active side rod, T is the time constant and s is the complex frequency domain variable in Laplace transform.

[0021] Preferably, as a further improvement of the present invention, the control law of the rod force closed-loop sliding mode control is:

[0022]

[0023] Among them, u1 is the output of the rod force closed-loop sliding mode control, x1=F1-F, F1 is the ideal rod force after softening, F is the actual rod force, c1 is the sliding surface adjustment parameter, ε1 and q1 are the reaching law parameters;

[0024] The sliding mode switching function is defined as: s1 = c1x1 + x2, the straight line s1 = 0 is the switching line, the state x slides back and forth on the switching line, and the conditions on both sides of the switching line are satisfied To ensure that in the area on either side of the switching line s1=0, the movement of state x is towards the switching line, and the convergence speed depends on the value of c1.

[0025] Preferably, as a further improvement of the present invention, the control law of the speed closed-loop sliding mode control is:

[0026]

[0027] Among them, u2 is the output of speed closed-loop sliding mode control, x3=ω * -ω,ω * is the ideal speed, ω is the actual speed, Where K t is the torque coefficient of the motor, J is the equivalent moment of inertia of the motor, c2 is the sliding surface adjustment parameter, ε2 and q2 are the reaching law parameters;

[0028] The sliding mode switching function is defined as: s2=c2x3+x4, the straight line s2=0 is the switching line, the state x slides back and forth on the switching line, and the conditions s2s&2≤0 are satisfied on both sides of the switching line to ensure that in the area on either side of the switching line s2=0, the movement of state x is towards the switching line, and the convergence speed depends on the c2 value.

[0029] Preferably, as a further improvement of the present invention, the control law is designed based on an exponential reaching law, and the exponential reaching law is: s&=-εsgn(s)-qs, wherein ε and q are reaching law parameters, and ε>0, q>0.

[0030] The present invention also discloses a control system for realizing the above-mentioned rod force servo control method for suppressing the redundant force of the active side rod, and the control system comprises:

[0031] A data acquisition unit, comprising a position sensor, a rod force sensor, a speed sensor and a current sensor, wherein the position sensor is used to detect the deflection angle of the active side rod push, the rod force sensor is used to collect and feedback the actual rod force felt by the driver when operating the side rod in real time, the speed sensor is used to detect and feedback the rotation speed in the motor, and the current sensor is used to detect and feedback the current in the motor;

[0032] A flight control computer is provided with a command generator and a command softener, wherein the command generator is used to convert the deflection angle of the active side stick pushed by the position sensor into an ideal stick force, and the command softener is used to soften the generated ideal stick force;

[0033] A data processing unit includes a rod force sliding mode controller, a speed sliding mode controller and a current controller, wherein the rod force sliding mode controller is used to receive a deviation value generated by the difference between the actual rod force and the softened ideal rod force, and output a reference command signal of the speed sliding mode controller after processing; the speed sliding mode controller is used to receive a deviation value generated by the difference between the output reference command signal of the speed sliding mode controller and the feedback motor speed signal, and output a reference command signal of the current controller after processing; the current controller is used to receive a deviation value generated by the difference between the output reference command signal of the current controller and the feedback motor current signal, and output a control signal after processing;

[0034] A signal conversion unit, which is an inverter, is used to convert the control signal output by the current controller into a drive signal for the motor;

[0035] The force feedback actuator comprises a motor and a mechanical transmission mechanism, wherein the mechanical transmission mechanism is a gear box and a transmission shaft, wherein the output shaft of the motor is connected to one end of the transmission shaft, the other end of the transmission shaft is connected to the input end of the gear box, and the output end of the gear box is connected to the active side rod handle.

[0036] Compared with the prior art, the present invention has the following beneficial effects:

[0037] 1. An active sidestick force servo control method is designed with sliding mode control theory as the core. This method has good dynamic performance and robustness. It uses closed-loop sliding mode control to eliminate cumulative errors and improve control accuracy. It can suppress the excess force phenomenon generated in the active sidestick force servo process, and then provide the driver with a natural and variable force feedback, so that the driver can feel the flight status of the aircraft through this force feedback, enhance human-computer interaction, and improve driving quality.

[0038] 2. An active side stick force servo control system is designed with sliding mode control theory as the core. When the pilot operates the active side stick, the position of the active side stick changes, and the resulting displacement is transmitted to the flight control computer in real time through the position sensor. The flight control computer simultaneously receives the flight state parameters of the aircraft, and calculates the theoretical stick force that the current force feedback actuator needs to achieve according to the stick force displacement model pre-established by the command generator. The controller outputs a drive signal to control the motor rotation and generate the required ideal stick force at the active side stick grip point. The command softener softens the ideal stick force, and the actual stick force detected by the stick force sensor and the softened ideal stick force output by the flight control computer form negative feedback. The current feedback from the current sensor and the speed feedback from the speed sensor form negative feedback with the output of the controller. After sliding mode control, the cumulative error is eliminated, and the closed-loop control of the system is used to improve the control accuracy of the system. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] Figure 1 is a control system diagram of the present invention;

[0040] Figure 2 It is a structural diagram of the rod force servo control of the present invention;

[0041] Figure 3 It is the working principle diagram of the rod force servo control of the present invention;

[0042] Figure 4 It is a rod force and rod displacement curve diagram of the present invention;

[0043] Figure 5 A comparison diagram of the ideal rod force of the present invention and the ideal rod force after softening;

[0044] Figure 6 This is a diagram showing the rod force servo following effect of the present invention;

[0045] Figure 7 This is the rod force following error diagram of the present invention. DETAILED DESCRIPTION

[0046] The following is combined with Figures 1 to 7 , the specific implementation methods of the present invention are described in detail. In the description of the invention, it should be understood that the terms "first" and "second" are used for descriptive purposes only and cannot be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Therefore, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features; in the description of the invention, unless otherwise specified, "multiple" means two or more.

[0047] Example 1

[0048] like Figures 1 to 7As shown, an embodiment of the present invention provides a rod force servo control method for suppressing the redundant force of an active side rod, comprising the following steps:

[0049] S1: Get the deflection angle of the active side stick push.

[0050] In this embodiment, the driver manually pushes the active side rod to a certain angle, and the deflection angle of the active side rod is detected by the position detection element.

[0051] S2: Determine the ideal rod force based on the deflection angle.

[0052] In this embodiment, the obtained deflection angle of the active side rod push is substituted into the rod force rod displacement curve, and the ideal rod force is determined by calculating the rod force rod displacement curve, wherein the rod force rod displacement curve is determined by the following formula:

[0053]

[0054] In the formula, F * is the ideal force of the active side stick, and θ is the deflection angle of the active side stick.

[0055] Among them, Figure 4 As shown, the rod force and displacement curve is set as a two-segment segmented function. The maximum rod force of the active side rod is 150N, and the deflection angle range of the active side rod is ±15°. At the same time, the starting force needs to be set. The starting force of the active side rod is set to 4N. When the active side rod rotates to 10°, the rod force corresponds to 90N (first gradient), and when the rotation angle is 15°, the rod force corresponds to 150N (second gradient). The first gradient is 12.6N / degree, and the second gradient is 12N / degree.

[0056] S3: Determine the ideal rod force after softening based on the ideal rod force.

[0057] In this embodiment, the ideal rod force is softened using the following formula:

[0058]

[0059] Where F1(s) is the Laplace transform of the ideal rod force after softening, F * (s) is the Laplace transform of the ideal force of the active side rod, T is the time constant and s is the complex frequency domain variable in Laplace transform.

[0060] According to the definition of T, the larger a is, the faster the response to the input signal is, and vice versa. Figure 5 As shown in the figure, the driver pushes the active side rod to an angle of θ, which is input in the form of a sine wave in the simulation. The ideal rod force is calculated through the rod force and rod displacement curve. Figure 5It can be seen that the ideal lever force will have a step-like drop at 0.31s, accompanied by a phase change, and a similar situation will occur at 0.63s. The function of the command softener is to eliminate this situation and make it drop slowly, in order to prevent the adverse consequences of the driver's fierce operation. The softened ideal lever force is the target value of the entire system servo tracking.

[0061] S4: Obtain the actual rod force of the active side rod, make a difference between the actual rod force obtained and the ideal rod force after softening, use the deviation value generated by the difference as the input signal, and output the first reference command signal through the rod force closed-loop sliding mode control.

[0062] In this embodiment, rod force closed-loop sliding mode control is used to process the deviation value generated by the difference between the actual rod force and the softened ideal rod force. The fundamental difference between the sliding mode control method used by the rod force closed-loop sliding mode control and some common control methods is that the control law and the structure of the closed-loop system are discontinuous on the sliding surface. Through appropriate design, the advantages of phase trajectory topologies under different structures can be combined to achieve the expected control performance. Therefore, it is insensitive to parameter changes and external disturbances and is a very robust control method. The control law of the rod force closed-loop sliding mode control is:

[0063]

[0064] Among them, u1 is the output of the rod force closed-loop sliding mode control, x1=F1-F, F1 is the ideal rod force after softening, F is the actual rod force, c1 is the sliding surface adjustment parameter, ε1 and q1 are the reaching law parameters.

[0065] The basic requirements of sliding mode control are as follows: ① Existence, that is, selecting the sliding mode function so that the motion of the control system on the switching surface is asymptotically stable and has good dynamic quality; ② Reachability, that is, determining the control action so that all motion trajectories reach the switching surface within a limited time.

[0066] The sliding mode switching function is defined as: s1 = c1x1 + x2, the straight line s1 = 0 is the switching line, the state x slides back and forth on the switching line, and the conditions on both sides of the switching line are satisfied To ensure that in the area on either side of the switching line s1=0, the movement of state x is towards the switching line, and the convergence speed depends on the value of c1.

[0067] The approaching law can improve the dynamic quality of the approaching motion, and the exponential approaching law is used to meet the above requirements. Set the exponential approaching law as: Where ε and q are the parameters of the approaching law, and ε>0, q>0. In the exponential approaching law, in order to ensure rapid approaching while weakening the jitter, ε should be reduced while increasing q; in the approaching motion stage, since the system error cannot be directly controlled, and the system response will be affected by the changes in internal parameters and external disturbances, therefore, when designing the approaching law, the time of the approaching motion stage must be shortened as much as possible.

[0068] S5: Subtract the output first reference command signal from the feedback motor speed signal, use the deviation value generated by the difference as the input signal, and output the second reference command signal through speed closed-loop sliding mode control.

[0069] The speed closed-loop sliding mode control in this embodiment is the inner loop of the cascade control. Its main function is to enhance the anti-disturbance capability of the control system and realize stable tracking of the control system. The sliding mode control method is also adopted because it is insensitive to parameter changes and external disturbances. It is a very robust control method. The design process is the same as that of the rod force closed-loop sliding mode control. Its control law is:

[0070]

[0071] Among them, u2 is the output of speed closed-loop sliding mode control, x3=ω * -ω,ω * is the ideal speed, ω is the actual speed, Where K t is the torque coefficient of the motor, J is the equivalent moment of inertia of the motor, c2 is the sliding surface adjustment parameter, ε2 and q2 are the reaching law parameters;

[0072] The sliding mode switching function is defined as: s2 = c2x3 + x4, the straight line s2 = 0 is the switching line, the state x slides back and forth on the switching line, and the conditions on both sides of the switching line are satisfied To ensure that in the area on either side of the switching line s2=0, the movement of state x is towards the switching line, and the convergence speed depends on the value of c2.

[0073] Similarly, the approach law can improve the dynamic quality of the approach motion, and the exponential approach law is used to meet the above requirements. Set the exponential approach law to: Where ε and q are the parameters of the approaching law, and ε>0, q>0. In the exponential approaching law, in order to ensure rapid approaching while weakening the jitter, ε should be reduced while increasing q; in the approaching motion stage, since the system error cannot be directly controlled, and the system response will be affected by the changes in internal parameters and external disturbances, therefore, when designing the approaching law, the time of the approaching motion stage must be shortened as much as possible.

[0074] S6: Subtract the output second reference command signal from the feedback current signal of the motor, input the deviation value generated by the difference into the current controller, and the current controller outputs a control signal.

[0075] Among them, the motor current is made to follow the current reference value quickly and without static error through the current controller to realize current closed-loop correction. The current controller adopts the conventional PI control method.

[0076] S7: Convert the output control signal into a driving signal of the motor, and the motor runs according to the driving signal.

[0077] In summary, due to the strong position disturbance of the active sidestick by the pilot, the inertia of the sidestick operating mechanism, and the time-varying nonlinearity in the system, in order to eliminate these interference factors, an active sidestick force servo control system and method are designed with sliding mode control theory as the core. This method has good dynamic performance and robustness. It uses the closed-loop control of the system to eliminate the cumulative error and improve the control accuracy of the system. It can suppress the excess force phenomenon generated in the active sidestick force servo process, and then provide the pilot with a natural and variable force feedback, so that the pilot can feel the flight status of the aircraft through this force feedback, enhance human-computer interaction, and improve driving quality.

[0078] Example 2

[0079] Based on the first embodiment, this embodiment discloses a control system for implementing the above-mentioned rod force servo control method for suppressing the redundant force of the active side rod, and the control system includes:

[0080] A data acquisition unit, comprising a position sensor, a rod force sensor, a speed sensor and a current sensor, wherein the position sensor is used to detect the deflection angle of the active side rod push, the rod force sensor is used to collect in real time the actual rod force felt by the driver when operating the side rod, the speed sensor is used to detect and feed back the rotation speed in the motor, and the current sensor is used to detect and feed back the current in the motor;

[0081] The flight control computer has a command generator and a command softener inside. The command generator is used to convert the deflection angle of the active side stick push detected by the position sensor into an ideal stick force, and the command softener is used to soften the generated ideal stick force;

[0082] The data processing unit includes a rod force sliding mode controller, a speed sliding mode controller and a current controller. The rod force sliding mode controller is used to receive a deviation value generated by the difference between the actual rod force and the softened ideal rod force, and output a reference command signal of the speed sliding mode controller after processing. The speed sliding mode controller is used to receive a deviation value generated by the difference between the output reference command signal of the speed sliding mode controller and the feedback motor speed signal, and output a reference command signal of the current controller after processing. The current controller is used to receive a deviation value generated by the difference between the output reference command signal of the current controller and the feedback motor current signal, and output a control signal after processing.

[0083] The signal conversion unit is an inverter, which is used to convert the control signal output by the output current controller into a drive signal for the motor;

[0084] The force feedback actuator comprises a motor and a mechanical transmission mechanism, wherein the motor is a three-phase permanent magnet synchronous motor, the mechanical transmission mechanism is a gear box and a transmission shaft, the output shaft of the motor is connected to one end of the transmission shaft, the other end of the transmission shaft is connected to the input end of the gear box, and the output end of the gear box is connected to the active side rod handle.

[0085] In this embodiment, a set of active side stick force servo control system is designed with sliding mode control theory as the core. When the pilot manipulates the active side stick, the position of the active side stick changes, and the generated displacement is transmitted to the flight control computer in real time through the position sensor. The flight control computer simultaneously receives the flight state parameters of the aircraft, and calculates the theoretical stick force that the current force feedback actuator needs to achieve according to the stick force displacement model pre-established by the instruction generator. The controller outputs a driving signal to control the motor to rotate, and the required ideal stick force is generated at the active side stick grip point. The instruction softener softens the ideal stick force, and the actual stick force detected by the stick force sensor and the softened ideal stick force output by the flight control computer form negative feedback. The current feedback by the current sensor and the speed feedback by the speed sensor form negative feedback with the output of the controller. After the sliding mode control, the cumulative error is eliminated, and the closed-loop control of the system is used to improve the control accuracy of the system.

[0086] It should be noted that, in the active mode, the basic equations of the motor and mechanical transmission mechanism in the aircraft active sidestick system are as shown below.

[0087]

[0088] Where, U is the motor voltage; R is the total resistance of the armature circuit; I is the armature current; L1 is the equivalent inductance of the armature circuit; E is the back electromotive force; K e is the back electromotive force coefficient; ω is the motor speed; T e is the electromagnetic torque; K t is the torque coefficient of the motor; J is the equivalent moment of inertia of the motor; T Lis the load moment; T d is the reaction torque transmitted from the motor load torque to the side handle; i is the transmission ratio of the gearbox; G c is the torque stiffness of the transmission shaft; θ0 is the rotation angle of the motor output shaft end; θ is the rotation angle of the side stick handle operated by the driver through mechanical transmission to the motor output shaft; F is the force feedback felt by the driver, that is, the actual stick force; L2 is the length of the side stick.

[0089] In the active mode, the motor output shaft will be subjected to a strong position disturbance caused by the driver pushing the active side stick, such as Figure 3 As shown in θ, the difference between the rotation angle θ0 and θ at the motor output shaft end is multiplied by the torque stiffness G c , we can get the load moment T L , as shown in the formula: T L =G c (θ0-θ). The load moment T L Multiplying by the gear ratio i of the gearbox gives the reaction torque T transmitted from the motor load torque to the side handle. d According to the basic equations of motors and mechanical transmission mechanisms, the reaction torque T d Dividing it by the side rod length L2 gives the actual rod force actually felt by the driver.

[0090] The designed active side stick force servo following effect is as follows Figure 6 As shown, the following effect is very good, with only a very small error at startup and when the rod force gradient changes. The rod force following error diagram is shown in Figure 7 As shown, the excess force has been suppressed to within ±1.3N, which is completely acceptable and can provide the driver with a natural and variable force feedback.

[0091] The above disclosures are only several preferred specific embodiments of the present invention. However, the embodiments of the present invention are not limited thereto. Any changes that can be conceived by those skilled in the art should fall within the protection scope of the present invention.

Claims

1. A rod force servo control method for suppressing excess force of an active side rod, characterized in that: The following steps are involved: Get the deflection angle of the active side stick push; Determine the ideal rod force based on the deflection angle; Determine the ideal rod force after softening based on the ideal rod force; The actual rod force of the active side rod is obtained, and the actual rod force obtained is subtracted from the ideal rod force after softening, and the deviation value generated by the subtraction is used as the input signal, and the first reference command signal is output through the rod force closed-loop sliding mode control; Subtract the output first reference command signal from the feedback motor speed signal, use the difference value generated by the difference as the input signal, and output a second reference command signal through speed closed-loop sliding mode control; Subtracting the output second reference command signal from the feedback current signal of the motor, inputting the deviation value generated by the difference into the current controller, and the current controller outputs a control signal; The output control signal is converted into a driving signal of the motor, and the motor operates according to the driving signal.

2. The rod force servo control method for suppressing the redundant force of the active side rod according to claim 1, characterized in that: The process of determining the ideal rod force according to the deflection angle is realized by calculating the rod force rod displacement curve, and the rod force rod displacement curve is determined by the following formula: In the formula, F * is the ideal force of the active side stick, and θ is the deflection angle of the active side stick.

3. The rod force servo control method for suppressing the redundant force of the active side rod according to claim 2, characterized in that: The ideal rod force is softened using the following formula: Where F1(s) is the Laplace transform of the ideal rod force after softening, F * (s) is the Laplace transform of the ideal force of the active side rod, T is the time constant and s is the complex frequency domain variable in Laplace transform.

4. The rod force servo control method for suppressing the redundant force of the active side rod according to claim 2, characterized in that: The control law of the rod force closed-loop sliding mode control is: Among them, u1 is the output of the rod force closed-loop sliding mode control, x1=F1-F, F1 is the ideal rod force after softening, F is the actual rod force, c1 is the sliding surface adjustment parameter, ε1 and q1 are the reaching law parameters; The sliding mode switching function is defined as: s1 = c1x1 + x2, the straight line s1 = 0 is the switching line, the state x slides back and forth on the switching line, and the conditions on both sides of the switching line are satisfied To ensure that in the area on either side of the switching line s1=0, the movement of state x is towards the switching line, and the convergence speed depends on the value of c1.

5. The rod force servo control method for suppressing the redundant force of the active side rod according to claim 4, characterized in that: The control law of the speed closed-loop sliding mode control is: Among them, u2 is the output of speed closed-loop sliding mode control, x3=ω * -ω,ω * is the ideal speed, ω is the actual speed, Where K t is the torque coefficient of the motor, J is the equivalent moment of inertia of the motor, c2 is the sliding surface adjustment parameter, ε2 and q2 are the reaching law parameters; The sliding mode switching function is defined as: s2 = c2x3 + x4, the straight line s2 = 0 is the switching line, the state x slides back and forth on the switching line, and the conditions on both sides of the switching line are satisfied To ensure that in the area on either side of the switching line s2=0, the movement of state x is towards the switching line, and the convergence speed depends on the value of c2.

6. The rod force servo control method for suppressing the redundant force of the active side rod according to claim 5, characterized in that: The control law is designed based on an exponential reaching law, and the exponential reaching law is: s&=-εsgn(s)-qs, wherein ε and q are reaching law parameters, and ε>0, q>0.

7. A control system, characterized in that: The control system is used to implement the rod force servo control method for suppressing the redundant force of the active side rod as claimed in any one of claims 1 to 6, and comprises: A data acquisition unit, comprising a position sensor, a rod force sensor, a speed sensor and a current sensor, wherein the position sensor is used to detect the deflection angle of the active side rod push, the rod force sensor is used to collect and feedback the actual rod force felt by the driver when operating the side rod in real time, the speed sensor is used to detect and feedback the rotation speed in the motor, and the current sensor is used to detect and feedback the current in the motor; A flight control computer is provided with a command generator and a command softener, wherein the command generator is used to convert the deflection angle of the active side stick pushed by the position sensor into an ideal stick force, and the command softener is used to soften the generated ideal stick force; A data processing unit includes a rod force sliding mode controller, a speed sliding mode controller and a current controller, wherein the rod force sliding mode controller is used to receive a deviation value generated by the difference between the actual rod force and the softened ideal rod force, and output a reference command signal of the speed sliding mode controller after processing; the speed sliding mode controller is used to receive a deviation value generated by the difference between the output reference command signal of the speed sliding mode controller and the feedback motor speed signal, and output a reference command signal of the current controller after processing; the current controller is used to receive a deviation value generated by the difference between the output reference command signal of the current controller and the feedback motor current signal, and output a control signal after processing; A signal conversion unit, which is an inverter, is used to convert the control signal output by the current controller into a drive signal for the motor; The force feedback actuator comprises a motor and a mechanical transmission mechanism, wherein the mechanical transmission mechanism is a gear box and a transmission shaft, wherein the output shaft of the motor is connected to one end of the transmission shaft, the other end of the transmission shaft is connected to the input end of the gear box, and the output end of the gear box is connected to the active side rod handle.

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