Hypersonic Wind Tunnel Dynamic Test Model Full-Motion Actuator and Its Control Method

Abstract

The present invention belongs to the technical field of hypersonic wind tunnel test, and discloses a full-motion actuator for a hypersonic wind tunnel dynamic test model and a control method thereof. The main body of the full-motion actuator is a frame, with a frameless motor and a control module installed at the front end, a transmission module and a rudder deflection angle detection module installed inside, a braking module installed at the rear end, and a full-motion rudder surface installed on the right rear side; the control module controls the frameless motor to drive the transmission module to drive the full-motion rudder surface to change the rudder deflection angle; the rudder deflection angle detection module measures the rudder deflection angle of the full-motion rudder surface; the braking module fixes the rudder deflection angle of the full-motion rudder surface. The control method includes determining the control objective of the full-motion actuator; establishing a mathematical model of the frameless motor servo controller; establishing a mathematical model of the frameless motor transmission structure; establishing a mathematical model of the rudder deflection angle detection module; establishing a servo control model of the actuator; and performing full-motion rudder surface control. The full-motion actuator and its control method achieve miniaturization, high load, and high precision, and can be applied to the dynamic wind tunnel test of hypersonic aircraft.

Description

Technical Field

[0001] The present invention belongs to the technical field of hypersonic wind tunnel tests, and particularly relates to a fully movable servo for a hypersonic wind tunnel dynamic test model and a control method thereof. Background Art

[0002] As a core component of a hypersonic aircraft, the form and performance of the servo system greatly affect the attitude control and performance of the hypersonic aircraft.

[0003] The servo system of the wind tunnel test model is used in the wind tunnel test of the variable rudder deflection of the dynamic test model to simulate various motion states of the hypersonic aircraft. The servo system of the wind tunnel test model is placed inside the test model and is reliably connected to the control rudder blade. It automatically moves according to the specified deflection angle to realize the automatic change of the rudder deflection angle of the dynamic test model, and can control and measure the attitude of the model rudder surface in real time and accurately, improving the measurement accuracy and efficiency of the model aerodynamic force.

[0004] Currently, the servo system of the wind tunnel test model is mainly applied to low-speed and subsonic and transonic wind tunnels. Generally, a small-load servo system for model aircraft or a real servo system used by aircraft is selected. Special servo systems will also be designed in some special simulation requirements.

[0005] Wang Hui et al. designed a servo composed of a displacement sensor, a controller, a connecting rod and a double hinge mechanism in the paper "Development of a Servo System for Wind Tunnel Test Models" published in the 3rd issue of Experimental Fluid Mechanics in 2012. The servo has a small volume, light weight, good load characteristics, and ideal temperature stability and stability against impact loads. The servo control accuracy is high, and the servo test accuracy is relatively high. It operates reliably in a low-speed wind tunnel. Using this servo, the efficiency of the full-aircraft rudder efficiency test of a certain aircraft was increased by 3 times, and the wind tunnel operation time was reduced by 36.5%.

[0006] In 2014, the Chinese patent literature database disclosed the invention named an automatic servo for a low-speed wind tunnel force measurement test model (ZL201420386906.7) by the team of Che Binghui. This patent designed a test model servo for a low-speed wind tunnel that integrates an elevator, a rudder and a control system. The test model automatically adjusts the rudder surface angle in the wind tunnel through computer control, and the efficiency is increased by 40% compared with manual adjustment of the rudder surface angle.

[0007] The paper "Optimal Design and Development of a Small Electric Actuator Transmission Mechanism" published by Liang Jianliang et al. in the 4th issue of "Mechanical Research & Application" in 2016 designed a small electric actuator transmission mechanism composed of a lead screw-nut pair and a linkage mechanism. This small electric actuator transmission mechanism improved the efficiency and accuracy of wind tunnel tests, increased the deflection angle of the actuator, enlarged the adjustment range of the deflection angle, and achieved a smooth change in the rotation speed of the actuator; the maximum rudder surface rotation angle given reached 69.89°, the average angular velocity was 2.331° / s, and the standard deviation of the angular velocity fluctuation was 0.0813.

[0008] In 2021, the research team of Zhang Haihang from Harbin Institute of Technology published a paper "Research on Electric Variable Rudder Surface System in Wind Tunnel Tests" in "Harbin Institute of Technology", which designed an actuator with a ball screw and a six-link structure, and conducted research on the electric variable rudder surface system installed inside the aircraft scaled model in wind tunnel tests, mainly from aspects such as structural optimization design, analysis of non-linear interference factors, and control methods. This actuator can withstand a certain amount of aerodynamic load, has locking ability and remote control ability, has relatively high measurement accuracy, improves the transmission efficiency, and has the advantages of small volume, light weight, few structural parts, low complexity, and high reliability.

[0009] In 2022, the Chinese patent literature database disclosed the invention named an actuator module for wind tunnel test model (ZL202223219584.0) by the research team of Li Guangliang. This patent designed a wind tunnel test model actuator using the method of rotating shaft pin, and realized the end feedback of the rudder deflection angle and the closed-loop control of the actuator through gears, transmission shafts, fork levers, and encoders. The accuracy of the rudder deflection angle of the actuator unit in wind tunnel tests is within 0.05°, and it has the advantages of small volume and high accuracy.

[0010] All in all, due to the low flow field wind speed and small simulated load in low-speed and subsonic / supersonic wind tunnels, the load on the actuator is not high; the low-speed and subsonic / supersonic wind tunnels have a large diameter, the test model is relatively large in size, and the allowable space for the actuator system is large, so the actuator can be relatively large in size; currently, the main application fields of the actuator system for wind tunnel test models are low-speed and subsonic / supersonic wind tunnels. In contrast, hypersonic wind tunnels have a small diameter, the test model is small in size, and the allowable space for the actuator system of the wind tunnel test model is even smaller. The hypersonic wind tunnel flow field simulates a high dynamic pressure, the load on the actuator system is large, and at the same time, the hypersonic wind tunnel dynamic test has high requirements for the control accuracy of the rudder surface deflection. The existing actuator systems for wind tunnel test models cannot be used in hypersonic wind tunnels.

[0011] Currently, in the field of hypersonic wind tunnel dynamic tests, there is also an urgent need to develop a corresponding actuator system for wind tunnel test models, and there is an urgent need to develop a full-motion actuator for hypersonic wind tunnel dynamic test models and its control method. Summary of the Invention

[0012] One technical problem to be solved by the present invention is to provide a fully movable rudder actuator for a hypersonic wind tunnel dynamic test model. Another technical problem to be solved by the present invention is to provide a control method for the fully movable rudder actuator of the hypersonic wind tunnel dynamic test model, so as to carry out the dynamic test research of the aircraft in the hypersonic wind tunnel.

[0013] The fully movable rudder actuator of the hypersonic wind tunnel dynamic test model of the present invention includes a frame, a frameless motor, a transmission module, a braking module, a rudder deflection angle detection module, a fully movable rudder surface and a control module;

[0014] The main body of the fully movable rudder actuator is the frame. The frameless motor and the control module are installed at the front end of the frame. The transmission module and the rudder deflection angle detection module are installed inside the frame. The braking module is installed at the rear end of the frame. The fully movable rudder surface is installed on the right rear side of the frame;

[0015] The control module controls the frameless motor to drive the transmission module to drive the fully movable rudder surface to change the rudder deflection angle; the rudder deflection angle detection module is used to measure the rudder deflection angle of the fully movable rudder surface; the braking module is used to fix the rudder deflection angle of the fully movable rudder surface.

[0016] Further, the frame includes a frame body, a motor mounting seat, a left cover plate, a right cover plate and a front cover plate;

[0017] The transmission module is installed in the inner cavity of the frame body; the front end face of the frame body is fixed with the motor mounting seat, and the frameless motor and the control module are fixedly installed on the motor mounting seat;

[0018] The left cover plate is installed at the left opening of the frame body, and the right cover plate is installed at the right opening of the frame body; the front cover plate is installed on the front end face of the motor mounting seat;

[0019] The frame body, the motor mounting seat, the left cover plate, the right cover plate and the front cover plate are all made of 7075 aluminum alloy material.

[0020] Further, the frameless motor includes a locking nut, a motor rotor, a motor stator and a motor fixing block;

[0021] The frameless motor is installed on the motor mounting seat and fixed to the front end of the frame body by screws;

[0022] When the frameless motor is powered on, the motor stator generates a rotating magnetic field to push the motor rotor to rotate; the locking nut fixedly connects the motor rotor to the lead screw of the lead screw nut assembly, and the motor rotor drives the lead screw to rotate, driving the nut of the lead screw nut assembly to perform a linear motion.

[0023] Further, the transmission module includes a lead screw nut assembly, a gear rack assembly and a rudder shaft assembly. The transmission module transmits the power output from the motor shaft of the frameless motor to the fully movable rudder surface through the lead screw nut assembly, the gear rack assembly and the rudder shaft assembly, driving the fully movable rudder surface to generate a rudder surface deflection movement;

[0024] The lead screw nut assembly includes a lead screw, a nut, a slider assembly, a cylindrical guide rod, a front bearing of the lead screw, a rear bearing of the lead screw, and a retaining ring; the slider assembly consists of a sliding bearing and a slider, the sliding bearing is installed inside the slider, and the sliding bearing and the cylindrical guide rod form a friction pair; the lead screw and the nut are located in the central cavity of the frame body, the slider assembly is installed on two cylindrical guide rods on both sides of the lead screw, and the nut is fixedly connected to the slider assembly by screws; the frameless motor drives the lead screw to rotate, and the nut drives the slider assembly to move along the cylindrical guide rod, converting the rotation of the lead screw into the linear motion of the slider;

[0025] The described gear rack assembly includes a rack, a gear, a gear flat key, and mechanical limit; the rack is fixed on the slider of the slider assembly, the rack meshes with the gear, the gear is connected to the steering shaft of the steering shaft assembly through the gear flat key, and the gear retaining ring fixes the axial position of the gear; when the frameless motor drives the lead screw nut assembly to move, the rack generates a linear motion along with the slider of the slider assembly, the rack meshes with the gear to drive the steering shaft to move, and the mechanical limit is parallel to the rack, which is used to limit the movement range of the slider, thereby limiting the steering angle adjustment range of the fully movable control surface;

[0026] The described steering shaft assembly includes a steering shaft, a power bearing, a steering shaft mounting base, a front bearing gland, and a rear bearing gland; the steering shaft is fixedly installed in the steering shaft mounting base through two sets of power bearings, a front bearing gland, and a rear bearing gland; the power bearings are in pairs, the inner rings of the power bearings are fixed on the steering shaft, and the friction and wear are reduced by the rolling of the rolling elements between the inner and outer rings; one end of the steering shaft is fixedly connected to the gear, and the other end of the steering shaft is fixedly connected to the fully movable control surface; when the frameless motor moves through the lead screw nut assembly and the gear rack assembly, the gear rack assembly drives the steering shaft to rotate, and the steering shaft drives the fully movable control surface to rotate, changing the steering angle of the fully movable control surface.

[0027] Further, the described braking module includes a DC electromagnetic brake, a brake block, a brake fixing block, a rear retaining ring, and a flat key;

[0028] The braking module is installed at the rear end of the lead screw, the rear retaining ring is fixed on the rear end face of the frame body, the brake block is connected to the frame body by screws, the DC electromagnetic brake is fixed on the brake block by screws, the brake fixing block is connected to the DC electromagnetic brake by a flat key, the upper half of the flat key is fixed in the key grooves of the brake fixing block and the DC electromagnetic brake, and the lower half of the flat key is fixed in the key groove of the lead screw; under the power-off condition, the electromagnetic force of the DC electromagnetic brake overcomes the spring force, releases the DC electromagnetic brake, and the DC electromagnetic brake clamps the flat key to prevent the lead screw from rotating when it is stationary or powered off; under the power-on condition, the spring force contracts the DC electromagnetic brake, releases the lead screw, and realizes braking.

[0029] Further, the described steering angle detection module includes a magnetic turntable, a magnetoresistive effect sensor, and a sensor mounting plate;

[0030] The magnetic turntable is fixed to the left end of the rudder shaft of the rudder shaft assembly and moves synchronously with the rudder shaft; the magnetoresistive effect sensor is fixedly installed on the sensor mounting plate, and the sensor mounting plate is fixed to the bottom surface of the frame body. The magnetoresistive effect sensor is matched and aligned with the magnetic turntable; the gear-rack assembly drives the rudder shaft to rotate, and the magnetic turntable rotates synchronously with the rudder shaft. The rotation of the magnetic turntable causes a change in the internal magnetic field strength, and the magnetoresistive effect sensor detects an analog signal related to the change in the magnetic field strength. The analog signal is collected and decoded by the host computer and then outputs the rudder deflection angle of the full-moving control surface.

[0031] Furthermore, the full-moving control surface includes a control surface body, a control surface bearing, a positioning assembly, a control surface bearing gland, a control surface upper cover, and a pin shaft;

[0032] The positioning assembly includes screws and positioning pins for connecting the full-moving control surface to the rudder shaft; the control surface upper cover is connected to the control surface body by screws, the control surface bearing gland fixes the control surface bearing to the left rear end face of the control surface body by screws, the pin shaft passes through the control surface bearing gland and the control surface bearing and is fixed to the left rear end face of the control surface body. The control surface bearing supports the pin shaft and reduces the friction when the pin shaft rotates.

[0033] Furthermore, the control module includes a control circuit and a connector. The control circuit is connected to the host computer through the connector, and the connector communicates with the host computer through the RS485 interface; the control module and the frameless motor are fixed on the motor mounting seat. The control module is located below the frameless motor, and the connector is installed on the front end face of the control module; when the host computer receives the rudder deflection angle output by the rudder deflection angle detection module, the host computer outputs a signal to the control module to control the movement of the frameless motor and perform feedback control until the full-moving control surface reaches the specified rudder deflection angle.

[0034] The control method of the full-moving actuator of the hypersonic wind tunnel dynamic test model of the present invention includes the following steps:

[0035] S10. Determine the control target of the full-moving actuator;

[0036] The full-moving actuator of the hypersonic wind tunnel dynamic test model operates in a constant force mode, and the working states include one or a combination of two or more of co-pushing, co-pulling, braking, and push-pull interlocking; the servo controller is developed with FPGA as the core, an electrical control program is established, and the frameless motor is controlled to drive the full-moving control surface to reach the specified rudder deflection angle;

[0037] S20. Establish a mathematical model of the frameless motor servo controller;

[0038] Establish a mathematical model of the frameless motor servo controller through Laplace transform;

[0039] Let the torque , and the mathematical model of the frameless motor servo controller is simplified to:

[0040] ,

[0041] ,

[0042] ;

[0043] Among them, is the rotation angle of the motor shaft relative to the initial position; is the DC bus voltage of the motor; is the electromagnetic time constant; is a complex variable in the frequency domain; is the motor time constant, ; is the inductance, is the resistance, is the load torque, is the back electromotive force constant, is the torque coefficient; then the transfer function of the motor :

[0044] ;

[0045] Among them, is the input voltage of the motor; is the electromotive force transfer system, , is the electromotive force coefficient; is the torque transfer system, ; , , ; is the electromagnetic time coefficient, is the torque coefficient, is the back electromotive force value, is the magnetic field intensity of the motor, is the diameter of the motor, is the current; is the change amount of the load torque in the complex frequency domain;

[0046] Substitute the relevant parameters to obtain the transfer function of the motor , among which, is the electromagnetic torque:

[0047] ;

[0048] After the driver amplifies the control signal output by the control module in power and drives the frameless motor, through mathematical modeling, it is a proportional link in the system ;

[0049] S30. Establish the mathematical model of the frameless motor drive structure;

[0050] The lead screw nut assembly 17 reduces the rotation angle output by the frameless motor and drives the rudder to deflect, which is also a proportional link ; Let , be the proportional coefficient of the drive structure and the transmission structure;

[0051] S40. Establish the mathematical model of the rudder deflection angle detection module;

[0052] The rudder deflection angle detection module converts the feedback signal of the full-moving rudder surface deflection position into an electrical signal and transmits it to the control module. The control module sends a control signal to the braking module, and the braking module cuts off the power for braking, forming a proportional link in the system, denoted as ;

[0053] S50. Establish the control model of the servo;

[0054] The simplified transfer function of the full-moving servo is written in the form of a differential equation as:

[0055] ;

[0056] Among them, is the time-domain constant; is the DC bus voltage of the motor, is the deflection angle of the full-moving rudder surface; is the derivative symbol, indicating the tiny change amount of with time; is the input voltage,

[0057] ;

[0058] Among them, is the maximum gain coefficient of the servo model; is the minimum gain coefficient of the servo model;

[0059] The differential equation of the input and output of the servo system is as follows:

[0060] ;

[0061] S60. Perform full-moving rudder surface control;

[0062] The control module sends a control signal to the electrical control program to drive the frameless motor to rotate. The power is transmitted to the fully movable control surface through the transmission module to drive the fully movable control surface to rotate. At the same time, the rudder deflection angle detection module real-time feedbacks the rudder deflection angle to determine whether the fully movable control surface reaches the specified position. If it reaches the specified position, the control module sends a control signal to the frameless motor and the braking module, and the frameless motor stops rotating, and the braking module performs power-off braking.

[0063] The fully movable control surface actuator and its control method for the hypersonic wind tunnel dynamic test model of the present invention have the following characteristics:

[0064] a. The structures of the actuator drive, transmission, and rudder deflection angle measurement units are compact and small in volume, and can be directly installed inside the test model, with a total weight of 2.48 kg;

[0065] b. The actuator has high repeatability accuracy and a wide motion range. The actuator motion speed ≥ 50° / s, the motion range ≥ ±30°, the motion positioning accuracy is 0.1°, and the repeatability accuracy is better than 0.1°, and it can accurately adjust the angle of the control surface in the hypersonic wind tunnel test;

[0066] c. The rudder deflection angle measurement has high accuracy and fast response. The rudder deflection angle measurement accuracy is better than 0.02°, the real-time performance is better than 1 ms, the delay error ≤ 5 ms, and the actuator overshoot ≤ 10%, and it can quickly adjust the angle of the control surface in the hypersonic wind tunnel test;

[0067] d. The actuator can realize automatic adjustment of the rudder deflection angle, and the displacement and control process of the automatic adjustment can be set and automatically executed according to requirements before the system runs, or the input position command can be executed in real time.

[0068] The fully movable control surface actuator of the hypersonic wind tunnel dynamic test model of the present invention has the characteristics of simple structure, small volume, high precision, and small delay. It adopts a lead screw nut - rack and pinion structure. Compared with the rotating shaft pin and lead screw nut - connecting rod mechanism, it has a compact structure, a smaller volume, and a larger angle change, and can be built into the fully movable control surface; the actuator has high motion positioning accuracy and repeatability accuracy, high rudder deflection angle measurement accuracy, and small delay, improving the measurement sensitivity and accuracy of the actuator.

[0069] The fully movable control surface actuator and its control method for the hypersonic wind tunnel dynamic test model of the present invention are based on mechanical transmission and control theory. The control module issues a control signal to the frameless motor to drive the frameless motor to rotate. The power is transmitted to the control surface shaft through the transmission module for speed reduction and torque increase to drive the control surface shaft to rotate. At the same time, the rudder deflection angle measurement sensor real-time feedbacks the rudder deflection angle measurement signal to determine whether it reaches the specified position.

[0070] The fully movable control surface actuator and its control method for the hypersonic wind tunnel dynamic test model of the present invention achieve miniaturization, high load, and high precision, and can be applied to the dynamic wind tunnel test of hypersonic aircraft, having engineering practical value. Brief Description of the Drawings

[0071] Figure 1 Schematic diagram of the overall structure of the servo of the full-moving servo of the hypersonic wind tunnel dynamic test model of the present invention;

[0072] Figure 2 Schematic diagram of the frame structure of the servo of the full-moving servo of the hypersonic wind tunnel dynamic test model of the present invention;

[0073] Figure 3 Schematic diagram of the frameless motor structure of the full-moving servo of the hypersonic wind tunnel dynamic test model of the present invention;

[0074] Figure 4 Schematic diagram of the transmission module structure of the full-moving servo of the hypersonic wind tunnel dynamic test model of the present invention;

[0075] Figure 5 Schematic diagram of the lead screw nut assembly structure in the drive transmission module of the full-moving servo of the hypersonic wind tunnel dynamic test model of the present invention;

[0076] Figure 6 Schematic diagram of the sectional structure of the slider assembly of the full-moving servo of the hypersonic wind tunnel dynamic test model of the present invention;

[0077] Figure 7 Schematic diagram of the gear rack assembly structure in the transmission module of the full-moving servo of the hypersonic wind tunnel dynamic test model of the present invention;

[0078] Figure 8 Schematic diagram of the rudder shaft assembly structure in the transmission module of the full-moving servo of the hypersonic wind tunnel dynamic test model of the present invention;

[0079] Figure 9 Schematic diagram of the braking module structure of the full-moving servo of the hypersonic wind tunnel dynamic test model of the present invention;

[0080] Figure 10 Schematic diagram of the rudder deflection angle detection module structure of the full-moving servo of the hypersonic wind tunnel dynamic test model of the present invention;

[0081] Figure 11 Schematic diagram of the full-moving rudder surface module structure of the full-moving servo of the hypersonic wind tunnel dynamic test model of the present invention;

[0082] Figure 12 Schematic diagram of the control module structure of the full-moving servo of the hypersonic wind tunnel dynamic test model of the present invention;

[0083] Figure 13 Schematic diagram of the overall explosion of the servo of the full-moving servo of the hypersonic wind tunnel dynamic test model of the present invention;

[0084] Figure 14 The servo control model for the fully movable rudder of the hypersonic wind tunnel dynamic test model of the present invention.

[0085] In the figure, 1. Frame; 2. Frameless motor; 3. Transmission module; 4. Braking module; 5. Rudder deflection angle detection module; 6. Fully movable rudder surface; 7. Control module; 8. Frame body; 9. Motor mounting base; 10. Left cover plate; 11. Right cover plate; 12. Front cover plate; 13. Locking nut; 14. Motor rotor; 15. Motor stator; 16. Motor fixing block; 17. Lead screw nut assembly; 18. Gear rack assembly; 19. Rudder shaft assembly; 20. Lead screw; 21. Nut; 22. Slide block assembly; 23. Cylindrical guide rod; 24. Front bearing of lead screw; 25. Rear bearing of lead screw; 26. Retaining ring; 27. Sliding bearing; 28. Slide block; 29. Rack; 30. Gear; 31. Gear flat key; 32. Mechanical limit; 33. Rudder shaft; 34. Power bearing; 35. Rudder shaft mounting base; 36. Front gland of bearing; 37. Rear gland of bearing; 38. DC electromagnetic brake; 39. Brake stop block; 40. Brake fixing block; 41. Rear retaining ring; 42. Flat key; 43. Magnetic turntable; 44. Magnetoresistive effect sensor; 45. Sensor mounting plate; 46. Rudder surface body; 47. Rudder surface bearing; 48. Positioning assembly; 49. Rudder surface bearing gland; 50. Upper cover plate of rudder surface; 51. Pin shaft; 52. Control circuit; 53. Connector. Detailed implementation manners

[0086] The present invention will be described in detail below with reference to the drawings and embodiments.

[0087] As Figure 1 、 Figure 13 shown, the fully movable rudder of the hypersonic wind tunnel dynamic test model of the present invention includes a frame 1, a frameless motor 2, a transmission module 3, a braking module 4, a rudder deflection angle detection module 5, a fully movable rudder surface 6 and a control module 7;

[0088] The main body of the fully movable rudder is the frame 1. The frameless motor 2 and the control module 7 are installed at the front end of the frame 1. The transmission module 3 and the rudder deflection angle detection module 5 are installed inside the frame 1. The braking module 4 is installed at the rear end of the frame 1. The fully movable rudder surface 6 is installed on the right rear side of the frame 1;

[0089] The control module 7 controls the frameless motor 2 to drive the transmission module 3 to drive the fully movable rudder surface 6 to change the rudder deflection angle. The rudder deflection angle detection module 5 is used to measure the rudder deflection angle of the fully movable rudder surface 6. The braking module 4 is used to fix the rudder deflection angle of the fully movable rudder surface 6.

[0090] Furthermore, as Figure 2 shown, the frame 1 includes a frame body 8, a motor mounting base 9, a left cover plate 10, a right cover plate 11 and a front cover plate 12;

[0091] The transmission module 3 is installed in the inner cavity of the frame body 8; the front end face of the frame body 8 is fixed with a motor mounting base 9, and a frameless motor 2 and a control module 7 are fixedly installed on the motor mounting base 9;

[0092] The left cover plate 10 is installed at the left opening of the frame body 8, and the right cover plate 11 is installed at the right opening of the frame body 8; the front cover plate 12 is installed on the front end face of the motor mounting base 9;

[0093] The frame body 8, the motor mounting base 9, the left cover plate 10, the right cover plate 11 and the front cover plate 12 are all made of 7075 aluminum alloy material to meet the strength, stiffness and weight reduction requirements of the servo.

[0094] Furthermore, as Figure 3 shown, the frameless motor 2 includes a locking nut 13, a motor rotor 14, a motor stator 15 and a motor fixing block 16;

[0095] The frameless motor 2 is installed on the motor mounting base 9 and is fixed to the front end of the frame body 8 by screws;

[0096] When the frameless motor 2 is powered on, the motor stator 15 generates a rotating magnetic field to drive the motor rotor 14 to rotate; the locking nut 13 fixedly connects the motor rotor 14 to the lead screw 20 of the lead screw nut assembly 17, and the motor rotor 14 drives the lead screw 20 to rotate, driving the nut 21 of the lead screw nut assembly 17 to perform a linear motion.

[0097] Furthermore, as Figure 4 shown, the transmission module 3 includes a lead screw nut assembly 17, a gear rack assembly 18 and a rudder shaft assembly 19. The transmission module 3 transmits the power output from the motor shaft of the frameless motor 2 to the full-moving rudder surface 6 through the lead screw nut assembly 17, the gear rack assembly 18 and the rudder shaft assembly 19, driving the full-moving rudder surface 6 to generate a rudder surface deflection motion;

[0098] As Figure 5 shown, the lead screw nut assembly 17 includes a lead screw 20, a nut 21, a slider assembly 22, a cylindrical guide rod 23, a front bearing 24 of the lead screw, a rear bearing 25 of the lead screw and a retaining ring 26; as Figure 6 shown, the slider assembly 22 is composed of a sliding bearing 27 and a slider 28. The sliding bearing 27 is installed inside the slider. The sliding bearing 27 and the cylindrical guide rod 23 form a friction pair, which can greatly reduce the friction loss and surface wear between the cylindrical guide rod 23 and the slider assembly 22; the lead screw 20 and the nut 21 are located in the central cavity of the frame body 8. The slider assembly 22 is installed on two cylindrical guide rods 23 on both sides of the lead screw 20. The nut 21 and the slider assembly 22 are fixedly connected by screws; the frameless motor 2 drives the lead screw 20 to rotate, and the nut 21 drives the slider assembly 22 to move along the cylindrical guide rod 23, converting the rotation of the lead screw 20 into a linear motion of the slider 28;

[0099] As Figure 7 shown, the rack and pinion assembly 18 includes a rack 29, a pinion 30, a pinion flat key 31, and a mechanical limit 32; the rack 29 is fixed on the slider 28 of the slider assembly 22, the rack 29 meshes with the pinion 30, the pinion 30 is connected to the rudder shaft 33 of the rudder shaft assembly 19 through the pinion flat key 31, and the pinion retaining ring fixes the axial position of the pinion 30; when the frameless motor 2 drives the lead screw nut assembly 17 to move, the rack 29 moves linearly with the slider 28 of the slider assembly 22, the rack 29 meshes with the pinion 30 to drive the rudder shaft 33 to move, and the mechanical limit 32 is parallel to the rack 29 and is used to limit the movement range of the slider 28, thereby limiting the rudder deflection angle adjustment range of the fully movable rudder surface 6;

[0100] As Figure 8 shown, the rudder shaft assembly 19 includes a rudder shaft 33, a power bearing 34, a rudder shaft mounting base 35, a bearing front gland 36, and a bearing rear gland 37; the rudder shaft 33 is fixedly installed in the rudder shaft mounting base 35 through two sets of power bearings 34, the bearing front gland 36, and the bearing rear gland 37; the power bearing 34 is a mechanical component that converts mechanical energy and kinetic energy into each other, replacing sliding friction with rolling friction. The power bearings 34 are grouped in pairs. The inner ring of the power bearing 34 is fixed on the rudder shaft 33, and the friction and wear are reduced by the rolling of the rolling elements between the inner and outer rings; one end of the rudder shaft 33 is fixedly connected to the pinion 30, and the other end of the rudder shaft 33 is fixedly connected to the fully movable rudder surface 6; when the frameless motor 2 moves through the lead screw nut assembly 17 and the rack and pinion assembly 18, the rack and pinion assembly 18 drives the rudder shaft 33 to rotate, and the rudder shaft 33 drives the fully movable rudder surface 6 to rotate, changing the rudder deflection angle of the fully movable rudder surface 6.

[0101] Further, as Figure 9 shown, the braking module 4 adopts the electromagnetic braking principle and includes a DC electromagnetic brake 38, a brake stop 39, a brake fixing block 40, a rear retaining ring 41, and a flat key 42;

[0102] The braking module 4 is installed at the rear end of the lead screw 20. The rear retaining ring 41 is fixed on the rear end face of the frame body 8. The brake stop 39 is connected to the frame body 8 by screws. The DC electromagnetic brake 38 is fixed on the brake stop 39 by screws. The brake fixing block 40 is connected to the DC electromagnetic brake 38 through the flat key 42. The upper half of the flat key 42 is fixed in the key grooves of the brake fixing block 40 and the DC electromagnetic brake 38, and the lower half of the flat key 42 is fixed in the key groove of the lead screw 20; under the power-off condition, the electromagnetic force of the DC electromagnetic brake 38 overcomes the spring force, releases the DC electromagnetic brake 38, and the DC electromagnetic brake 38 catches the flat key 42 to prevent the lead screw 20 from rotating when it is stationary or powered off; under the power-on condition, the spring force contracts the DC electromagnetic brake 38 to release the lead screw 20 to achieve braking.

[0103] Further, as Figure 10 shown, the rudder deflection angle detection module 5 includes a magnetic turntable 43, a magnetoresistive effect sensor 44, and a sensor mounting plate 45;

[0104] The magnetic turntable 43 is fixed to the left end of the rudder shaft 33 of the rudder shaft assembly 19 and moves synchronously with the rudder shaft 33; the magnetoresistive effect sensor 44 is fixedly installed on the sensor mounting plate 45, and the sensor mounting plate 45 is fixed to the bottom surface of the frame body 8. The magnetoresistive effect sensor 44 is matched and aligned with the magnetic turntable 43; the rack and pinion assembly 18 drives the rudder shaft 33 to rotate, and the magnetic turntable 43 rotates synchronously with the rudder shaft 33. The rotation of the magnetic turntable 43 causes a change in the internal magnetic field strength, and the magnetoresistive effect sensor 44 detects an analog signal related to the change in the magnetic field strength. The analog signal is collected and decoded by the upper computer and then outputs the rudder deflection angle of the fully movable rudder surface 6.

[0105] Further, as Figure 11 shown, the fully movable rudder surface 6 includes a rudder surface main body 46, a rudder surface bearing 47, a positioning assembly 48, a rudder surface bearing gland 49, an upper cover plate 50 of the rudder surface, and a pin shaft 51;

[0106] The positioning assembly 48 includes screws and positioning pins and is used to connect the fully movable rudder surface 6 to the rudder shaft 33; the upper cover plate 50 of the rudder surface is connected to the rudder surface main body 46 by screws, the rudder surface bearing gland 49 fixes the rudder surface bearing 47 to the left rear end face of the rudder surface main body 46 by screws, and the pin shaft 51 passes through the rudder surface bearing gland 49 and the rudder surface bearing 47 and is fixed to the left rear end face of the rudder surface main body 46. The rudder surface bearing 47 supports the pin shaft 51 and reduces the friction when the pin shaft 51 rotates, ensuring that the rudder surface main body 46 accurately adjusts the rudder deflection angle.

[0107] Further, as Figure 12 shown, the control module 7 includes a control circuit 52 and a connector 53. The control circuit 52 is connected to the upper computer through the connector 53, and the connector 53 communicates with the upper computer through the RS485 interface; the control module 7 and the frameless motor 2 are fixed on the motor mounting seat 9, the control module 7 is located below the frameless motor 2, and the connector 53 is installed on the front end face of the control module 7; when the upper computer receives the rudder deflection angle output by the rudder deflection angle detection module 5, the upper computer outputs a signal to the control module 7 to control the movement of the frameless motor 2 and perform feedback control until the fully movable rudder surface 6 reaches the specified rudder deflection angle.

[0108] The control method of the fully movable rudder actuator of the hypersonic wind tunnel dynamic test model of the present invention includes the following steps:

[0109] S10. Determine the control target of the fully movable rudder actuator;

[0110] In the hypersonic wind tunnel dynamic test model, the fully movable rudder actuator operates in a constant force mode, and its working states include one or a combination of two or more of co-pushing, co-pulling, braking, and push-pull interlocking. Due to the complex control scheme and the lack of applicable off-the-shelf servo controllers, a self-developed servo controller has to be used. To ensure precise positioning, the servo controller needs to have complex functions and fast response capabilities. The servo controller is developed with an FPGA as the core, and an electrical control program is established to control the frameless motor 2 to drive the fully movable rudder surface 6 to reach the specified rudder deflection angle.

[0111] S20. Establish the mathematical model of the frameless motor 2 servo controller;

[0112] Establish the mathematical model of the frameless motor 2 servo controller through Laplace transform;

[0113] Let the torque , the mathematical model of the frameless motor 2 servo controller is simplified to:

[0114] ,

[0115] ,

[0116] ;

[0117] Among them, is the rotation angle of the motor shaft relative to the initial position; is the DC bus voltage of the motor; is the electromagnetic time constant; is a complex variable in the frequency domain; is the motor time constant, ; is the inductance, is the resistance, is the load torque, is the electromotive force constant, is the torque coefficient; then the transfer function of the motor :

[0118] ;

[0119] Among them, is the motor input voltage; is the electromotive force transfer system, , is the electromotive force coefficient; is the torque transfer system, ; , , ; is the electromagnetic time coefficient, is the torque coefficient, is the back electromotive force value, is the magnetic field intensity of the motor, is the diameter of the motor, is the current; is the change of the load torque in the complex frequency domain;

[0120] Substitute the relevant parameters to obtain the transfer function of the motor , where, is the electromagnetic torque:

[0121] ;

[0122] After the driver amplifies the control signal output by the control module 7 in power, it drives the frameless motor 2. After mathematical modeling, it is a proportional link in the system ;

[0123] S30. Establish the mathematical model of the transmission structure of the frameless motor 2;

[0124] The lead screw nut assembly 17 reduces the rotation angle output by the frameless motor 2 and drives the rudder blade to deflect, which is also a proportional link Let , is the proportional coefficient of the drive structure and the transmission structure;

[0125] S40. Establish the mathematical model of the rudder deflection angle detection module 5;

[0126] The rudder deflection angle detection module 5 converts the feedback signal of the deflection position of the full-moving rudder surface 6 into an electrical signal and transmits it to the control module 7. The control module 7 sends a control signal to the braking module 4, and the braking module 4 performs power-off braking, forming a proportional link in the system, denoted as ;

[0127] S50. Establish the steering gear control model;

[0128] Establish the steering gear control model as shown in Figure 14 ;

[0129] The simplified transfer function of the full-moving steering gear in differential equation form is:

[0130] ;

[0131] Where, is the time-domain constant; is the DC bus voltage of the motor, is the deflection angle of the full-moving rudder surface 6; is the derivative symbol, indicating the tiny change with time; is the input voltage, is the output voltage; According to the performance parameters of the frameless motor 2 and the design index requirements of the rudder deflection angle, the theoretical parameters of the servo model are obtained as follows:

[0132] ;

[0133] Among them, is the maximum gain coefficient of the servo model; is the minimum gain coefficient of the servo model;

[0134] The differential equation of the input and output of the servo system is as follows:

[0135] ;

[0136] S60. Perform full-moving rudder surface 6 control;

[0137] The control module 7 sends a control signal to the electrical control program to drive the frameless motor 2 to rotate. The power is transmitted to the full-moving rudder surface 6 through the transmission module 3 to drive the full-moving rudder surface 6 to rotate. At the same time, the rudder deflection angle detection module 5 real-time feedbacks the rudder deflection angle to judge whether the full-moving rudder surface 6 reaches the specified position. If it reaches the specified position, the control module 7 sends a control signal to the frameless motor 2 and the braking module 4. The frameless motor 2 stops rotating, and the braking module 4 performs power-off braking.

[0138] Embodiment: The full-moving servo of the hypersonic wind tunnel dynamic test model in this embodiment and its control method meet the following relevant technical indicators and requirements:

[0139] 1. It can achieve automatic locking and unlocking, and the braking torque of the servo ≥ 60 Nm;

[0140] 2. Load index: The rated output torque of a single servo ≥ 50 Nm; The maximum load torque ≥ 100 Nm; The mass of the servo ≤ 5 kg;

[0141] 3. Motion index: The motion range ≥ ±30°, the motion positioning accuracy 0.1°, the repeatability accuracy 0.1°, and the servo motion speed ≥ 50° / s;

[0142] 4. Servo measurement and control technical indicators: The measurement accuracy of the rudder deflection angle is better than 0.02°, the real-time performance of the rudder deflection angle measurement is better than 1 ms, the deflection delay error of the full-moving rudder surface 6 ≤ 5 ms, the overshoot of the servo ≤ 10%, and the servo system bandwidth (dynamic response) ≥ 5 Hz.

[0143] The selection process of the main components of the full-moving servo of the hypersonic wind tunnel dynamic test model in this embodiment is as follows:

[0144] 1. Frameless motor 2: This embodiment requires the servo system to have the following three output parameters: deflection angle range: 32° to -32°, output torque: 100 Nm, deflection angle angular velocity: 50° / s. The frameless motor 2 adopts a direct drive design without considering the reducer parameters. Substitute the output parameters and structural parameters into the calculation program for calculation. The calculation results are as follows: Under the working condition of a maximum of 100 Nm, the lead screw speed is 7853.98 rpm, the input torque of the lead screw is 0.158 Nm, the input power of the lead screw is 130 W, and the transmission clearance error of the servo system is 0.038°. It is required that the maximum speed of the frameless motor 2 is 10,000 rpm, the maximum torque is 11.050 Nm, and there is sufficient reserve space for speed and torque to ensure that the servo movement speed > 50° / s, the movement range > ±30°, the rudder deflection angle positioning accuracy < 0.1°, and the repeatability accuracy is better than 0.1°. After the frameless motor 2 of this embodiment increases the torque through the lead screw nut assembly, the rated thrust of the lead screw nut assembly is 7800 N, which fully meets the requirements of the servo. The frameless motor 2 selects the maxon ecXXframeless flat frameless motor, with a maximum speed of 10,000 rpm and a maximum torque of 11.050 Nm;

[0145] 2. Braking module 4: The braking module 4 utilizes the electromagnetic braking principle and is installed at the rear end of the lead screw 20. The lead of the lead screw 20 is 0.25 mm, and the pitch circle radius of the gear is 15 mm. To achieve a braking torque of 60 Nm, only 0.29 Nm needs to be loaded at the input end of the lead screw 20. When selecting the DC electromagnetic brake 38, it only needs to be greater than 0.29 Nm. This embodiment requires the working voltage of the DC electromagnetic brake 38 to be 24 V, the braking torque: 0.4 Nm, the braking torque is greater than 0.3 Nm, and the braking torque generated by the mechanism is greater than 85 Nm, which is better than the requirement of braking 60 Nm. The DC electromagnetic brake 38 adopts the AB28 DC permanent magnet and dry brake of MAXON. The braking torque generated after increasing the torque through the lead screw 20 is greater than 85 Nm, meeting the requirements of automatic locking or unlocking.

[0146] Although the embodiments of the present invention have been disclosed as above, they are not limited to the applications listed in the specification and embodiments. For those familiar with the art, without departing from the principle of the present invention, all the features disclosed in the present invention, or all the steps in the disclosed methods or processes, except for mutually exclusive features and / or steps, can be combined in any way. The present invention is not limited to the specific details and the illustrated examples here.

Claims

1. Hypersonic wind tunnel dynamic test model full-motion steering gear, characterized in that: The fully movable steering gear comprises a frame (1), a frameless motor (2), a transmission module (3), a brake module (4), a rudder angle detection module (5), a fully movable steering surface (6) and a control module (7); The main body of the full-motion steering gear is a frame (1), a frameless motor (2) and a control module (7) are installed at the front end of the frame (1), a transmission module (3) and a rudder angle detection module (5) are installed inside the frame (1), a brake module (4) is installed at the rear end of the frame (1), and a full-motion steering surface (6) is installed on the right rear side of the frame (1); The control module (7) controls the frameless motor (2) to drive the transmission module (3) to drive the fully movable rudder surface (6) to change the rudder deflection angle; the rudder deflection angle detection module (5) is used to measure the rudder deflection angle of the fully movable rudder surface (6); and the brake module (4) is used to fix the rudder deflection angle of the fully movable rudder surface (6); The transmission module (3) comprises a screw nut assembly (17), a gear rack assembly (18) and a rudder shaft assembly (19); the transmission module (3) transmits power output from the motor shaft of the frameless motor (2) to the full-moving rudder surface (6) via the screw nut assembly (17), the gear rack assembly (18) and the rudder shaft assembly (19), thereby driving the full-moving rudder surface (6) to generate rudder surface deflection movement; The lead screw nut assembly (17) comprises a lead screw (20), a nut (21), a slider assembly (22), a cylindrical guide rod (23), a lead screw front end bearing (24), a lead screw rear end bearing (25) and a retaining ring (26); the slider assembly (22) comprises a sliding bearing (27) and a slider (28), the sliding bearing (27) is mounted inside the slider, and the sliding bearing (27) and the cylindrical guide rod (23) form a friction pair; the lead screw (20) and the nut (21) are located in the central cavity of the frame body (8), the slider assembly (22) is mounted on two cylindrical guide rods (23) on both sides of the lead screw (20), and the nut (21) and the slider assembly (22) are fixedly connected by screws; the frameless motor (2) drives the lead screw (20) to rotate, and the nut (21) drives the slider assembly (22) to move along the cylindrical guide rod (23), thereby converting the rotation of the lead screw (20) into the linear motion of the slider (28); The rack and pinion assembly (18) comprises a rack (29), a gear (30), a gear flat key (31) and a mechanical limiter (32); the rack (29) is fixed on a slider (28) of a slider assembly (22); the rack (29) meshes with the gear (30); the gear (30) is connected to a rudder shaft (33) of a rudder shaft assembly (19) via a gear flat key (31); and a gear retaining ring fixes the axial position of the gear (30); when the frameless motor (2) drives the lead screw nut assembly (17) to move, the rack (29) generates linear motion along with the slider (28) of the slider assembly (22); the rack (29) meshes with the gear (30) to drive the rudder shaft (33) to move; the mechanical limiter (32) is parallel to the rack (29) and is used to limit the motion range of the slider (28), thereby limiting the rudder angle adjustment range of the full-motion rudder surface (6); The rudder shaft assembly (19) comprises a rudder shaft (33), a dynamic bearing (34), a rudder shaft mounting base (35), a bearing front pressure cover (36) and a bearing rear pressure cover (37); the rudder shaft (33) is fixedly mounted in the rudder shaft mounting base (35) through two sets of dynamic bearings (34), the bearing front pressure cover (36) and the bearing rear pressure cover (37); the dynamic bearings (34) are arranged in groups of two, the inner rings of the dynamic bearings (34) are fixed on the rudder shaft (33), and the friction and wear are reduced by the rolling of the rolling bodies between the inner and outer rings; one end of the rudder shaft (33) is fixedly connected to the gear (30), and the other end of the rudder shaft (33) is fixedly connected to the full-motion rudder surface (6); when the frameless motor (2) moves through the screw nut assembly (17) and the gear rack assembly (18), the gear rack assembly (18) drives the rudder shaft (33) to rotate, and the rudder shaft (33) drives the full-motion rudder surface (6) to rotate, thereby changing the rudder deflection angle of the full-motion rudder surface (6).

2. The hypersonic wind tunnel dynamic test model full-motion steering gear according to claim 1, characterized in that: The frame (1) comprises a frame body (8), a motor mounting seat (9), a left cover plate (10), a right cover plate (11) and a front cover plate (12); The transmission module (3) is installed in the inner cavity of the frame body (8); the motor mounting seat (9) is fixed to the front end surface of the frame body (8), and the frameless motor (2) and the control module (7) are fixedly installed on the motor mounting seat (9); The left cover plate (10) is mounted on the left opening of the frame body (8), and the right cover plate (11) is mounted on the right opening of the frame body (8); the front cover plate (12) is mounted on the front end surface of the motor mounting seat (9); The frame body (8), the motor mounting seat (9), the left cover plate (10), the right cover plate (11) and the front cover plate (12) are all made of 7075 aluminum alloy material.

3. The hypersonic wind tunnel dynamic test model full-moving steering gear according to claim 2, characterized in that: The frameless motor (2) comprises a locking nut (13), a motor rotor (14), a motor stator (15) and a motor fixing block (16); The frameless motor (2) is mounted on a motor mounting seat (9) and fixed to the front end of the frame body (8) by screws; When the frameless motor (2) is powered on, the motor stator (15) generates a rotating magnetic field, which drives the motor rotor (14) to rotate; the locking nut (13) fixedly connects the motor rotor (14) and the lead screw (20) of the lead screw nut assembly (17); the motor rotor (14) drives the lead screw (20) to rotate, and drives the nut (21) of the lead screw nut assembly (17) to perform linear motion.

4. The hypersonic wind tunnel dynamic test model full-moving steering gear according to claim 3, characterized in that: The brake module (4) comprises a DC electromagnetic brake (38), a brake block (39), a brake fixing block (40), a rear retaining ring (41) and a flat key (42); The brake module (4) is installed at the rear end of the lead screw (20), the rear retaining ring (41) is fixed to the rear end surface of the frame body (8), the brake block (39) is connected to the frame body (8) by screws, the DC electromagnetic brake (38) is fixed to the brake block (39) by screws, the brake fixing block (40) is connected to the DC electromagnetic brake (38) by a flat key (42), the upper part of the flat key (42) is fixed to the key slots of the brake fixing block (40) and the DC electromagnetic brake (38), and the lower part of the flat key (42) is fixed in the key slot of the lead screw (20); when the power is off, the electromagnetic force of the DC electromagnetic brake (38) overcomes the spring force to release the DC electromagnetic brake (38), and the DC electromagnetic brake (38) clamps the flat key (42) to prevent the lead screw (20) from rotating when it is stationary or powered off; when the power is on, the spring force contracts the DC electromagnetic brake (38) to release the lead screw (20) to achieve braking.

5. The hypersonic wind tunnel dynamic test model full-motion steering gear according to claim 4, characterized in that: The rudder angle detection module (5) comprises a magnetic turntable (43), a magnetoresistive effect sensor (44) and a sensor mounting plate (45); The magnetic turntable (43) is fixed to the left end of the rudder shaft (33) of the rudder shaft assembly (19) and moves synchronously with the rudder shaft (33); the magnetoresistance effect sensor (44) is fixedly mounted on a sensor mounting plate (45), the sensor mounting plate (45) is fixed to the bottom surface of the frame body (8), and the magnetoresistance effect sensor (44) matches and is aligned with the magnetic turntable (43); the gear rack assembly (18) drives the rudder shaft (33) to rotate, and the magnetic turntable (43) rotates synchronously with the rudder shaft (33), the rotation of the magnetic turntable (43) causes the internal magnetic field intensity to change, and the magnetoresistance effect sensor (44) detects an analog signal related to the change in magnetic field intensity, and the analog signal is collected and decoded by a host computer to output the rudder deflection angle of the full-motion rudder surface (6).

6. The hypersonic wind tunnel dynamic test model full-moving steering gear according to claim 5, characterized in that: The fully movable rudder surface (6) comprises a rudder surface body (46), a rudder surface bearing (47), a positioning assembly (48), a rudder surface bearing gland (49), a rudder surface upper cover plate (50) and a pin shaft (51); The positioning assembly (48) comprises screws and positioning pins, and is used to connect the fully movable rudder surface (6) and the rudder shaft (33); the rudder surface upper cover plate (50) is connected to the rudder surface body (46) by means of screws; the rudder surface bearing pressure cover (49) fixes the rudder surface bearing (47) to the left rear end surface of the rudder surface body (46) by means of screws; the pin shaft (51) passes through the rudder surface bearing pressure cover (49) and the rudder surface bearing (47) and is fixed to the left rear end surface of the rudder surface body (46); the rudder surface bearing (47) supports the pin shaft (51) and reduces friction when the pin shaft (51) rotates.

7. The hypersonic wind tunnel dynamic test model full-motion steering gear according to claim 6, characterized in that: The control module (7) comprises a control circuit (52) and a connector (53), the control circuit (52) is connected to a host computer via the connector (53), and the connector (53) communicates with the host computer via an RS485 interface; the control module (7) and the frameless motor (2) are fixed on a motor mounting seat (9), the control module (7) is located below the frameless motor (2), and the connector (53) is mounted on a front end surface of the control module (7); when the host computer receives the rudder deflection angle output by the rudder deflection angle detection module (5), the host computer outputs a signal to the control module (7), controls the movement of the frameless motor (2), and performs feedback control until the full-moving rudder surface (6) reaches a specified rudder deflection angle.

8. A control method for a hypersonic wind tunnel dynamic test model full-motion steering gear, which is used for a hypersonic wind tunnel dynamic test model full-motion steering gear as claimed in any one of claims 1 to 7, characterized in that: The control method comprises the following steps: S10. Determine the control target of the full-motion servo; The full-moving servo of the hypersonic wind tunnel dynamic test model works in a constant force mode, and the working state includes one or a combination of two or more of co-pushing, co-pulling, braking, and push-pull interlocking; the servo controller is developed with FPGA as the core, and an electrical control program is established to control the frameless motor (2) to drive the full-moving rudder surface (6) to reach a specified rudder deflection angle; S20. Establishing a mathematical model of the servo controller of the frameless motor (2); Establish the mathematical model of the frameless motor (2) servo controller through Laplace transform; Torque , the mathematical model of the frameless motor (2) servo controller is simplified to: ， ， ； in, is the rotation angle of the motor shaft relative to the initial position; is the DC bus voltage of the motor; is the electromagnetic time constant; is a complex variable in the frequency domain; is the motor time constant, ; is the inductor, is the resistance, is the load torque, is the electromotive force constant, is the torque coefficient; then the transfer function of the motor : ； in, Input voltage to the motor; It is the electromotive force transmission system. , is the electromotive force coefficient; is the torque transmission system, ; , , ; is the electromagnetic time coefficient, is the torque coefficient, is the back EMF value, is the magnetic field strength of the motor, is the diameter of the motor, is the current; is the change of load torque in the complex frequency domain; Substitute the relevant parameters to get the transfer function of the motor ,in, is the electromagnetic torque: ； The driver amplifies the control signal output by the control module (7) and drives the frameless motor (2). After mathematical modeling, it is a proportional link in the system. ; S30. Establishing a mathematical model of the transmission structure of the frameless motor (2); The lead screw nut assembly (17) decelerates the rotation angle output by the frameless motor (2) and drives the rudder blade to deflect, which is also a proportional link. ;make , is the proportional coefficient between the driving structure and the transmission structure; S40. Establishing a mathematical model of the rudder angle detection module (5); The rudder deflection angle detection module (5) converts the deflection position feedback signal of the full-moving rudder surface (6) into an electrical signal and transmits it to the control module (7). The control module (7) sends a control signal to the brake module (4). The brake module (4) is powered off and brakes, forming a proportional link in the system, which is recorded as ; S50. Establish a steering gear control model; The simplified full-motion servo transfer function is written in the form of a differential equation: ； in, is a time domain constant; is the DC bus voltage of the motor, is the deflection angle of the all-movable control surface (6); is the derivative symbol, which means Small changes in volume over time; is the input voltage, is the output voltage; according to the performance parameters of the selected frameless motor (2) and the rudder angle design index requirements, the theoretical parameters of the servo model are obtained as follows: ； in, is the maximum gain coefficient of the servo model; is the minimum gain coefficient of the servo model; The differential equation of the input and output of the servo system is as follows: ； S60. Perform full-motion control of the rudder surface (6); The control module (7) sends a control signal to the electrical control program to drive the frameless motor (2) to rotate, and transmits power to the full-moving rudder surface (6) through the transmission module (3), driving the full-moving rudder surface (6) to rotate. At the same time, the rudder deflection angle detection module (5) feeds back the rudder deflection angle in real time to determine whether the full-moving rudder surface (6) has reached a specified position. If the specified position has been reached, the control module (7) sends a control signal to the frameless motor (2) and the brake module (4), the frameless motor (2) stops rotating, and the brake module (4) is powered off for braking.

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