Simulated aerodynamic load test system and test method of flap driving system

Abstract

The invention relates to a simulated aerodynamic load test system and method for a flap driving system, and belongs to the technical field of rotors, the simulated aerodynamic load test system comprises a support and a flap frame fixedly arranged on the support, a flap is horizontally arranged on one side of the flap frame, a driving mechanism is arranged on the flap frame, and the output end of the driving mechanism is connected with the flap. The connecting rod is horizontally arranged at one end of the flap, the two elastic pieces are vertically arranged between the connecting rod and the support, one end of each elastic piece is connected with the support, and the other end of each elastic piece is connected with the connecting rod in a sliding mode in the length direction of the connecting rod. Load inertia of an actual flap driving system in a paddle can be simulated, the load test effect of the flap driving system is improved, the load applied to the flap can be changed by using two symmetrically-distributed adjustable elastic pieces, loads of various sizes can be provided for up-down deflection of the flap, and the test efficiency is improved. Therefore, the convenience of the load test of the flap driving system is effectively improved.

Description

Technical Field

[0001] The present invention belongs to the technical field of rotors, and particularly relates to a simulated aerodynamic load test system and a test method for a flap drive system. Background Art

[0002] Traditional helicopters mainly achieve blade pitch change through a swashplate. With the rapid development of modern electronic power technology, advanced materials, and rotor design and manufacturing technology, foreign countries have proposed an electric control rotor manipulation technology in combination with a trailing edge servo flap system. The electric control rotor is a rotor manipulation system that embeds an electric actuator inside the blade or at the hub and drives the flap to deflect through a rod system, thereby generating a pitching moment relative to the blade pitch axis and finally changing the blade pitch. This manipulation method has the following advantages compared with the traditional helicopter rotor manipulation system: The electric control rotor manipulation system cancels the swashplate, mechanical control rod system, and hydraulic equipment, thus greatly improving the weight efficiency of the helicopter and enhancing the reliability, maintainability, and safety of the helicopter; The cancellation of the swashplate and mechanical rod system can reduce the hub profile drag and improve the aerodynamic efficiency of the whole aircraft; In addition, after adding high-order harmonic control to the control of the flap, the noise and vibration levels of the blade can be effectively reduced. It can be seen that the electric control rotor is a product of the combination of traditional technology evolution and the application of the latest technology. Its unique modern features and many advantages determine that the electric control rotor system has a bright application prospect and represents the development direction of a new generation of rotors.

[0003] In the process of developing the blade of the electric control rotor, it is very necessary to conduct a preliminary verification of the flap drive system. By installing a load device at the flap end to simulate aerodynamic forces, designing the control scheme of the actuator, and observing the operating condition of the entire flap drive system under different control modes when the flap is under load. Evaluating the performance of the flap drive system before the formal rotor test can improve the reliability during the formal rotor test. At the same time, it ensures that the scheme can be adjusted in time when the expected result of the flap drive system does not match the preliminary verification result, shortening the rotor development cycle.

[0004] Currently, the existing methods for load testing the flap drive system in the field of electric control rotors include: directly applying or using a flexible beam and a spring to apply a simulated aerodynamic load at the designed rotor speed at the actuator shaft end.

[0005] First, directly apply a simulated aerodynamic load at the designed rotor speed at the actuator shaft end, and then collect the motor deflection angle signal through a Hall sensor. Since the flap drive in the field of electric control rotors needs to consider the factor of the internal space size of the blade, indirect drive is mostly used. If the load inertia of the rod system is not considered during the test, it is easy to affect the flap deflection effect during the later rotor experiment.

[0006] Second, install a flexible beam at the flap to provide load for the flap drive system. However, in this test method, one material can only provide one load value. When simulating the aerodynamic loads at other rotational speeds of the rotor, it is necessary to replace the flexible beam, making the load test of the flap drive system relatively complex.

[0007] Third, use a high-power actuator. Since the inertia of the flap drive rod system has little influence on the power output of the actuator, the load inertia of the rod system can be ignored. The prior art is to arrange 4 springs in a cross structure at the output shaft end of the high-power actuator to simulate the aerodynamic load, and detect the deflection angle of the actuator through an angle sensor. However, in this test method, the installation position of the spring needs to be fixed. When simulating the aerodynamic loads at other rotational speeds of the rotor, it is necessary to re-design the structural parameters of the spring, such as the length, wire diameter, material, and number of turns of the spring, etc., making the load test of the flap drive system relatively complex. Summary of the Invention

[0008] In view of this, the present invention provides a simulated aerodynamic load test system and test method for a flap drive system, which can simulate the load inertia of the actual flap drive system inside the blade, provide various sizes of loads for the up and down deflection of the flap, and effectively improve the effect and convenience of the load test of the flap drive system, so as to solve the deficiencies in the prior art.

[0009] The technical solution of the present invention is: a simulated aerodynamic load test system for a flap drive system, including a bracket and a flap bracket fixed on the bracket. The flap is horizontally arranged on one side of the flap bracket. The flap is hinged to the flap bracket, and the hinge axis is parallel to the length direction of the flap. The drive mechanism is arranged on the flap bracket, and the output end of the drive mechanism is connected to the flap to drive the flap to deflect around its hinge axis. The connecting rod is horizontally arranged at one end of the flap and is perpendicular to the hinge axis of the flap. Two elastic members are vertically arranged between the connecting rod and the bracket. The two elastic members are symmetrically arranged with respect to the center line of the hinge axis of the flap. One end of the elastic member is connected to the bracket, and the other end is slidably connected to it along the length direction of the connecting rod. Move the two elastic members symmetrically along the length direction of the connecting rod, and lock the positions of the elastic members through the locking members to change the load applied to the flap.

[0010] Preferably, an axle attachment is horizontally fixed at one end of the flap. The axle attachment is coaxial with the center line of the hinge axis of the flap. The connecting rod horizontally passes through the axle attachment and is fixedly connected to it. The other end of the axle attachment is rotatably connected to the bracket around its circumference.

[0011] Preferably, the locking member includes: two pairs of lock nuts. The two pairs of lock nuts are sleeved on the connecting rod and are threadedly connected to it. The end of the elastic member away from the bracket is sleeved on the connecting rod. The two lock nuts in each pair are located on both sides of the elastic member and are respectively abutted against it.

[0012] Preferably, an angle sensor is fixedly provided on the hinge axis of the flap.

[0013] Preferably, the drive mechanism includes: a rotary power element, a rocker arm, and an eccentric wheel. The rotary power element is fixedly provided on the flap frame, the eccentric wheel is coaxially fixedly provided on the output shaft of the rotary power element, one end of the rocker arm is sleeved on the eccentric shaft of the eccentric wheel, the eccentric shaft is rotationally connected with the rocker arm around its circumference, and the other end of the rocker arm is hinged to the flap.

[0014] Preferably, it further includes: a single-quadrant controller, which is signal-connected to the rotary power element to output a control signal to drive the rotary power element to drive the flap to deflect.

[0015] Preferably, a temperature sensor is fixedly provided on the rotary power element, and an angle sensor is fixedly provided on the hinge axis of the flap.

[0016] A method for simulating aerodynamic load test of a flap drive system, based on a simulation aerodynamic load test system of the flap drive system, the test method includes the following steps: S1. By symmetrically moving two elastic members, the load applied by the elastic members to the flap is adjusted; S2. By controlling the rotary power element to drive the flap to perform a deflection movement; S3. By the angle sensor, the deflection angle information of the flap is collected, and according to the deflection angle information, a deflection movement curve of the flap is drawn. By the temperature sensor, the temperature information of the rotary power element is collected, and according to the temperature information, a temperature change curve of the rotary power element is drawn; S4. Compare whether the deflection movement curve of the flap conforms to the deflection movement curve of the flap under the rotor design speed and observe whether the temperature change curve of the rotary power element is within the safe operating temperature range. If the deflection movement curve of the flap conforms to the deflection movement curve of the flap under the rotor design speed and the temperature change curve of the rotary power element is within the safe operating temperature range, the test is stopped. If not, adjust the load applied to the flap, and repeat the above steps S2 - S4 until the deflection movement curve of the flap conforms to the deflection movement curve of the flap under the rotor design speed and the temperature change curve of the rotary power element is within the safe operating temperature range.

[0017] Preferably, the control signals for controlling the rotary power element include: single-frequency signals, mixed-frequency signals, and step signals, and the single-frequency signals, mixed-frequency signals, and step signals are obtained by editing the speed, direction of the rotary power element, and the frequency, amplitude, and duty cycle of the disable signal.

[0018] Preferably, for the single-frequency signal, the ratio of the speed and direction of the rotating power element to the amplitude, duty cycle, and frequency ratio of the disabling signal is 2:1:2; for the mixed-frequency signal, the ratio of the speed and direction of the rotating power element to the amplitude, duty cycle, and frequency ratio of the disabling signal is 4:1:4; for the step signal, the ratio of the speed and direction of the rotating power element to the amplitude, duty cycle, and frequency ratio of the disabling signal is 2:1:2.

[0019] Compared with the prior art, the simulated aerodynamic load test system and test method for a flap drive system provided by the present invention, through the cooperation of a bracket, a flap bracket, a flap, a drive mechanism, a connecting rod, and an elastic member, the drive mechanism drives the flap to deflect up and down on the flap bracket, can simulate the load inertia of the actual flap drive system inside the blade, improve the load test effect of the flap drive system, and then utilize two symmetrically distributed and adjustable elastic members on the connecting rod to change the load applied to the flap, so as to provide various sizes of loads for the up and down deflection of the flap, thereby effectively improving the convenience of the load test of the flap drive system. Description of the Drawings

[0020] Figure 1 is the flowchart of the load test method of the present invention; Figure 2 is the overall view of the load test system of the present invention; Figure 3 is the perspective view of the load test system of the present invention; Figure 4 is the top view of the load test system of the present invention; Figure 5 is the simplified diagram of the flap drive structure of the present invention; Figure 6 is the design schematic diagram of the four-bar mechanism of the present invention; Figure 7 is the schematic diagram of the flap deflection of the present invention; Figure 8 is the single-frequency, mixed-frequency, and step motion control signal diagrams of the flap of the present invention, where (a) is the single-frequency motion trajectory of the flap, (b) is the single-frequency motion speed control of the flap, (c) is the single-frequency motion direction control of the flap, (d) is the single-frequency motion disabling control of the flap, (e) is the mixed-frequency motion trajectory of the flap, (f) is the mixed-frequency motion speed control of the flap, (g) is the mixed-frequency motion direction control of the flap, (h) is the mixed-frequency motion disabling control of the flap, (i) is the step motion trajectory of the flap, (j) is the step motion speed control of the flap, (k) is the step motion direction control of the flap, (l) is the step motion disabling control of the flap.

[0021] Description of the Reference Numerals: 1. Load fixing table; 2. Bench vice; 3. Motor sleeve; 4. Temperature sensor; 5. Rotary power element; 6. Rocker arm; 7. Eccentric wheel; 8. Flap frame; 9. Flap; 10. Angle sensor; 11. Flap hinge joint frame; 12. Thrust ball bearing; 13. L-shaped angle piece; 14. Bolt; 15. Connecting rod; 16. Shaft accessory; 17. Locking nut; 18. Fixed angle piece; 19. Experimental tabletop; 21. Elastic member. Detailed implementation manner

[0022] The present invention provides a simulated aerodynamic load test system and test method for a flap drive system. The following will be described in conjunction with Figures 1 to 8 the structural schematic diagram of the present invention.

[0023] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "axial", "radial", "circumferential", etc. indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings. It is only for the convenience of describing the technical solution of the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be construed as a limitation to the present invention.

[0024] Figure 3 is a perspective view of the load test system of this embodiment. As Figure 3 shown, a simulated aerodynamic load test system for a flap drive system includes a bracket and a flap frame 8 fixedly arranged on the bracket. The flap 9 is horizontally arranged on one side of the flap frame 8. The flap 9 is hinged to the flap frame 8, and the hinge axis is parallel to the length direction of the flap 9. The driving mechanism is arranged on the flap frame 8, and the output end of the driving mechanism is connected to the flap 9 to drive the flap 9 to deflect around its hinge axis. The connecting rod 15 is horizontally arranged at one end of the flap 9 and is perpendicular to the hinge axis of the flap 9. Two elastic members 21 are vertically arranged between the connecting rod 15 and the bracket. The two elastic members 21 are symmetrically arranged with respect to the center line of the hinge axis of the flap 9. One end of the elastic member 21 is connected to the bracket, and the other end is slidably connected to it along the length direction of the connecting rod 15. Move the two elastic members 21 symmetrically along the length direction of the connecting rod 15, and lock the positions of the elastic members 21 through the locking members to change the load applied to the flap 9.

[0025] The simulated aerodynamic load test system of the flap drive system in this embodiment hinges the flap 9 on the flap frame 8, and then uses the drive mechanism on the flap frame 8 to drive the flap 9 to deflect up and down, so as to be able to simulate the load inertia of the actual flap drive system inside the blade, avoiding affecting the flap deflection effect during the later rotor experiment. Then, two adjustable elastic members 21 symmetrically distributed on the connecting rod 15 are used. The elastic members 21 are symmetrically distributed on the connecting rod 15, which can ensure that the load torques provided for the up and down deflection of the flap 9 are the same. By symmetrically moving the two elastic members 21 along the length direction of the connecting rod 15, the load applied to the flap can be changed, so as to provide various sizes of loads for the up and down deflection of the flap, and thus be able to simulate the aerodynamic torque at the flap under the design rotational speed of the rotor, effectively improving the convenience of the load test of the flap drive system.

[0026] In this embodiment, a flap hinge joint frame 11 can be arranged on the side of the flap 9 close to the flap frame. The flap hinge joint frame 11 is hinged to the flap frame 8, and the flap hinge joint frame 11 and the flap 9 are fixedly connected by assembly with a high-strength adhesive.

[0027] In this embodiment, the bracket includes a load fixing table 1, an L-shaped angle piece 13, and a fixing angle piece 18. Symmetrically arranged counterbored holes are provided on the load fixing table 1. The two counterbored holes are located on both sides of the flap 9 and are parallel to its length direction. Fixing angle pieces 18 are respectively arranged on the side of the counterbored holes close to the connecting rod 15. The fixing angle pieces 18 are fixedly connected to the load fixing table 1 by bolts 14. The end of the elastic member 21 far from the connecting rod 15 is connected to the fixing angle piece 18. The elastic member 21 is a tension spring. The elastic member 21 is installed after being stretched a certain length during installation to prevent the inherent length of the elastic member 21 itself from affecting the normal deflection of the flap 9 when it is compressed. Two L-shaped angle pieces 13 are arranged on the counterbored hole close to the flap frame 8. The L-shaped angle pieces 13 are fixedly connected to the load fixing table 1 by bolts 14. The flap frame 8 is respectively fixedly connected to the vertical ends of the L-shaped angle pieces 13. The positions of the L-shaped angle pieces 13 and the fixing angle pieces 18 can be adjusted through the counterbored holes, which is convenient for reuse when the sizes of the flap and the drive mechanism change.

[0028] Figure 2 is the overall view of the load test system in this embodiment, as Figure 2 shown. To reduce the high-frequency vibration generated during the operation of the flap drive system, the material of the load fixing table 1 is 45# steel, and the load fixing table 1 is fixed on the experimental table 19 by two bench vises 2, so as to reduce the influence of the vibration generated during the operation of the flap drive system on the test results.

[0029] As a further optimization solution, in this embodiment, a shaft accessory 16 is horizontally and fixedly arranged at one end of the flap 9. The shaft accessory 16 is coaxial with the center line of the hinge shaft of the flap 9. The connecting rod 15 horizontally passes through the shaft accessory 16 and is fixedly connected thereto. The other end of the shaft accessory 16 is rotationally connected to the bracket around its circumference.

[0030] In this embodiment, the shaft accessory 16 is used to cooperate with the elastic member 21 to apply a load to the flap 9. The shaft accessory 16 is rotationally connected to the bracket, so that when the flap 9 deflects up and down, the shaft accessory 16 can rotate synchronously, thereby improving the stability of applying the load to the flap 9.

[0031] Specifically, the connecting rod 15 passes through the shaft accessory 16. The two ends of the connecting rod 15 are symmetric with respect to the center line of the shaft accessory 16. The connecting rod 15 is fixedly connected to the shaft accessory 16 by screws to prevent loosening caused by the vibration during the movement of the connecting rod 15 and the shaft accessory 16 during the test.

[0032] As a further optimization solution, in this embodiment, the locking member includes: two pairs of lock nuts 17. The two pairs of lock nuts 17 are sleeved on the connecting rod 15 and are threadedly connected thereto. The end of the elastic member 21 away from the bracket is sleeved on the connecting rod 15. The two lock nuts 17 of each pair are located on both sides of the elastic member 21 and are respectively in contact with it.

[0033] In this embodiment, the connecting rod 15 is a threaded rod. After symmetrically moving the two elastic members 21 along the length direction of the connecting rod 15 to change the load applied to the flap 9, the positions of the elastic members 21 are fixed by the cooperation of the two lock nuts 17 and the threaded rod, so as to keep the load applied to the flap 9 stable.

[0034] Figure 4 is the top view of the load test system of this embodiment. As Figure 4 shown, as a further optimization solution, in this embodiment, a specific structure of a driving mechanism is given. The driving mechanism includes: a rotary power element 5, a rocker arm 6, and an eccentric wheel 7. The rotary power element 5 is fixedly arranged on the flap bracket 8. The eccentric wheel 7 is coaxially fixedly arranged on the output shaft of the rotary power element 5. One end of the rocker arm 6 is sleeved on the eccentric shaft of the eccentric wheel 7. The eccentric shaft is rotationally connected to the rocker arm 6 around its circumference. The other end of the rocker arm 6 is hinged to the flap 9.

[0035] In this embodiment, the rotary power element 5 of the driving mechanism adopts a brushless DC motor. The brushless DC motor cooperates with the rocker arm 6 and the eccentric wheel 7 to realize large-angle deflection of the flap 9 and meet the requirement of the flap deflection angle under the condition of high rotor speed.

[0036] Specifically, one end of the rocker arm 6 away from the eccentric wheel 7 is hinged to the flap hinge joint bracket 11. The hinge axis of the rocker arm 6 and the flap hinge joint bracket 11 is parallel and non-coaxial with the center line of the hinge axis of the flap hinge joint bracket 11 and the flap bracket 8.

[0037] The transmission principle of the driving mechanism is as Figure 5 shown, and it can be simplified into a planar four-bar mechanism. The position CO of the first crank, the position OA of the frame, the position BA of the second crank, and the position BC of the connecting rod are designed according to the predetermined angular displacements of the first crank and the second crank. First, determine the dimensions of the first crank and the frame and the preset deflection angles of the first crank and the second crank according to the designed airfoil dimensions. As Figure 6 shown, it is stipulated that the upward deflection of the flap is positive. The position CO of the first crank corresponds to the non-deflection of the flap, the position C1O of the first crank corresponds to the downward deflection of the flap, and the position C2O of the first crank corresponds to the upward deflection of the flap. Connect points C1 and C2 to point A respectively and draw arcs with A as the center and C1A and C2A as the radii according to the preset negative angle of the position BA of the second crank to obtain points C1' and C2'. The center of the circle formed by the three points C, C1', and C2' is the position of point B. Then connect BC to obtain the dimensions of the four-bar mechanism, and convert the deflection of the first crank into the deflection of the second crank, that is, realize the deflection from the rotary power element 5 to the flap 9.

[0038] When the rotor rotates, the centrifugal force will affect the flap drive system embedded inside the blade. Therefore, there are two eccentric wheels 7, and the eccentric shafts of the two eccentric wheels 7 are coaxially fixedly connected. The rocker arm 6 is sleeved on the eccentric shafts of the two eccentric wheels 7. One of the eccentric wheels 7 is coaxially fixedly connected to the output shaft of the rotary power element 5, and the other eccentric wheel 7 is rotatably connected to the flap bracket 8. In addition, thrust ball bearings 12 are installed at the hinge joint of the rocker arm 6 and the flap hinge joint bracket 11 and at the connection of the eccentric wheel 7 and the flap bracket 8 to reduce the influence of the centrifugal force on the flap drive system.

[0039] When the rotor works at a high rotational speed, the flap drive system will work in a strong and complex aerodynamic field, which requires the driving mechanism to have sufficient strength to meet the working requirements. Therefore, the materials of the rotary power element 5, the rocker arm 6, and the eccentric wheel 7 of the driving mechanism are made of hard aluminum alloy.

[0040] The temperature control of the rotary power element 5 in the driving mechanism of the foregoing embodiment is also a factor that cannot be ignored. Since the flap drive system needs to be embedded inside the rotor, the space inside the rotor is narrow and the heat dissipation is poor. If the temperature of the rotary power element 5 during operation cannot be controlled, the situation of reduced motor power or damage is likely to occur.

[0041] Therefore, when the rotary power element 5 is installed on the flap frame 8 in this embodiment, a motor sleeve 3 is sleeved outside the rotary power element 5. The motor sleeve 3 is fixedly connected to the flap frame 8. The material of the motor sleeve 3 is aluminum alloy. The heat generated by the operation of the rotary power element 5 is transferred to the flap frame 8 through the motor sleeve 3 to dissipate heat from the rotary power element 5, thereby realizing the cooling of the rotary power element 5.

[0042] In addition, in the above embodiment, a layer of thermal conductive adhesive is applied to the contact surface between the motor sleeve 3 and the flap frame 8 to improve the efficiency of heat transfer from the motor sleeve 3 to the flap frame 8, and further improve the cooling effect on the rotary power element 5.

[0043] As a further optimization scheme, this embodiment further includes: a single-quadrant controller, which is signal-connected to the rotary power element 5 to output a control signal to make the rotary power element 5 drive the flap 9 to deflect.

[0044] In this embodiment, through the single-quadrant controller, it is possible to receive a voltage signal to control the speed, direction, and start and stop of the power output of the rotary power element 5. The principle of controlling the rotary power element 5 by this method is as follows: when the rotary power element 5 drives the flap 9 to deflect upward to the designed angle, a disable command is sent to the rotary power element 5. At this time, the flap 9 decelerates to a stop and moves reversely back to the equilibrium position under the action of the symmetric moment of the elastic member 21. Then, a start and commutation command is sent to the rotary power element 5. After the flap 9 deflects reversely to the designed angle, it is disabled again, and then returns to the equilibrium position again under the action of the symmetric equilibrium moment of the elastic member 21. The above is a cycle of deflection movement of the rotary power element 5 driving the flap 9.

[0045] At the same time, by using the disable function of the single-quadrant controller and adopting high and low level control, it is avoided that the rotary power element 5 continuously operates, resulting in a gradual increase in temperature, a decrease in output power, or damage, so that the temperature of the rotary power element 5 is controlled below the safe temperature.

[0046] As a further optimization scheme, a temperature sensor 4 is fixedly provided on the rotary power element 5 in this embodiment, and an angle sensor 10 is fixedly provided on the hinge shaft of the flap 9.

[0047] In this embodiment, by setting the temperature sensor 4 on the rotary power element 5, the temperature information of the rotary power element 5 is collected by the temperature sensor 4. An angle sensor 10 is set on the hinge shaft of the flap 9, and the angle information of the up and down deflection of the flap 9 is collected by the angle sensor 10.

[0048] Specifically, the temperature sensor 4 consists of a surface-mounted platinum resistance sensor and a voltage transmitter. The platinum resistance sensor is pasted on the body of the rotary power element 5. As the body temperature of the rotary power element 5 gradually increases during operation, the temperature sensor 4 converts the temperature variable into a resistance variable, then into a voltage variable through the voltage transmitter, and finally the voltage signal is converted into a temperature variable and displayed through the acquisition card and the upper computer.

[0049] Specifically, the angle sensor 10 calibrated for voltage / angle is installed on the hinge axis of the flap hinge joint bracket 11 and the flap bracket 8. When the flap 9 deflects, the hinge axis rotates synchronously. The angle variable is converted into a voltage variable by the angle sensor 10, the acquisition card collects the voltage signal, and finally the voltage signal is converted into an angle variable and displayed through the calibration formula of the upper computer.

[0050] Figure 1 is a flowchart of the load test method of this embodiment. As Figure 1 shown, a method for simulating the aerodynamic load test of a flap drive system, based on the aerodynamic load test system of the flap drive system, the test method includes the following steps: S1. By symmetrically moving the two elastic members 21, the load applied by the elastic members 21 to the flap 9 is adjusted; S2. By controlling the rotary power element 5 to drive the flap 9 to perform a deflection movement; S3. By the angle sensor 10, collect the deflection angle information of the flap 9, draw the deflection movement curve of the flap 9 according to the deflection angle information, collect the temperature information of the rotary power element 5 by the temperature sensor 4, and draw the temperature change curve of the rotary power element 5 according to the temperature information; S4. Compare whether the deflection movement curve of the flap 9 conforms to the deflection movement curve of the flap 9 at the designed rotor speed and observe whether the temperature change curve of the rotary power element 5 is within the safe operating temperature range. If the deflection movement curve of the flap 9 conforms to the deflection movement curve of the flap 9 at the designed rotor speed and the temperature change curve of the rotary power element 5 is within the safe operating temperature range, stop the test. If not, adjust the load applied to the flap 9 and repeat the above steps S2 - S4 until the deflection movement curve of the flap 9 conforms to the deflection movement curve of the flap 9 at the designed rotor speed and the temperature change curve of the rotary power element 5 is within the safe operating temperature range.

[0051] The test method in this embodiment can relatively completely simulate the operating conditions of the entire flap drive system under load, making the preliminary evaluation results of the flap drive system more reliable before the rotor experiment.

[0052] As a further optimization solution, in this embodiment, the control signals for controlling the rotary power element 5 include: single-frequency signals, mixed-frequency signals, and step signals. The single-frequency signals, mixed-frequency signals, and step signals are obtained by editing the speed, direction of the rotary power element 5, and the frequency, amplitude, and duty cycle of the disable signal.

[0053] The test method in this embodiment takes into account that different operating modes of the electric control rotor have different requirements for the flap deflection movement. Therefore, three motion control signals for the flap, namely single-frequency, mixed-frequency, and step signals, are proposed. Through the single-frequency signal, mixed-frequency signal, and step signal, the rotary power element 5 drives the flap 9 to perform corresponding single-frequency, mixed-frequency, and step deflection movements, which can reduce the vibration, noise generated during the operation of the rotor, and the temperature of the rotary power element 5 during operation, and prevent the output power of the rotary power element 5 from decreasing or being damaged.

[0054] In this embodiment, the single-frequency signal, mixed-frequency signal, and step signal are respectively edited by a function signal generator.

[0055] When the designed rotor rotates, the aerodynamic torque at the flap is calculated by an aerodynamic simulation software. The position of the elastic member 21 is adjusted to simulate the aerodynamic torque at the flap 9 at the designed rotor speed. The frequency of the flap 9 deflection is calculated according to the designed rotor speed, and then the control signal is used to make the rotary power element 5 drive the flap 9 to perform a deflection movement. Single-frequency signal editing: Specifically, the load required for the single-frequency deflection movement of the flap 9 is adjusted. The function signal generator is used to adjust the settings such as the frequency, duty cycle, amplitude, and phase correlation of the control signal, and the single-frequency control signal of the flap 9 is sent to make the rotary power element 5 drive the flap 9 to deflect. The angle sensor 10 is used to collect the angle change waveform diagrams of the flap in multiple cycles to observe whether the frequency and deflection amplitude meet the design values. The temperature sensor 4 is used to collect the temperature of the rotary power element 5 during the flap deflection process to see if it is within the safe operating temperature standard.

[0056] Mixed-frequency signal editing: Specifically, the load required for the mixed-frequency deflection movement of the flap 9 is adjusted. The programming software is used to write the custom square wave signal for mixed-frequency control. The waveform data is exported through excel and imported into the upper computer of the function signal generator and then sent to the single-quadrant controller, so as to control the rotary power element 5 to drive the flap 9 to deflect. The angle sensor 10 is used to collect the angle change waveform diagrams of the flap in multiple cycles to observe whether the large-angle and small-angle curves of the flap 9 deflection are periodic, symmetric, and whether there is a problem of missing waves when using the mixed-frequency signal control. The temperature sensor 4 is used to collect the temperature of the rotary power element 5 during the flap deflection process to see if it is within the safe operating temperature standard.

[0057] Step signal editing: Specifically, the load required for the 9-step flap deflection movement is adjusted. A custom staircase wave signal for mixing control is written using programming software, and the waveform data is exported through excel and imported into the host computer of the function signal generator and then sent to the single-quadrant controller, so as to control the rotation of the power element 5 to drive the flap 9 to deflect. The angle sensor 10 is used to collect the angle change waveform diagrams of the flap in multiple cycles, and observe whether the multiple angle amplitudes of the flap 9 deflection after being controlled by the step signal meet the expectations and the repeatability of the angle deflection. The temperature sensor 4 is used to collect whether the temperature of the rotation power element 5 is within the safe operating temperature standard during the flap deflection process.

[0058] Compare whether the collected flap deflection motion curve and the motor temperature change curve meet the expected goals. If not, adjust the position of the elastic member 21, change the load size and ensure the symmetry of the load. At the same time, accurately adjust the amplitude, duty cycle and frequency of the voltage control signal, and repeat the test until it meets the expected standard.

[0059] Specifically, the test process is as follows: Use aluminum alloy to manufacture the test system by mechanical processing and assemble it; By symmetrically moving the positions of the two elastic members, the length of the force arm is controlled, so as to control the load applied to the flap; The angle sensor is used to convert the deflection angle of the flap into voltage, and through the data acquisition card and programming software, the voltage signal is converted into an angle signal output using the voltage / angle calibration formula; A platinum resistance temperature sensor patch is installed on the rotation power element, and the resistance-voltage-temperature conversion is realized through a voltage transmitter and a data acquisition card, so as to detect the temperature of the rotation power element; According to the designed rotor speed, calculate the frequency of the flap deflection, and then design single-frequency signals, mixed-frequency signals and step signals through the function signal generator to control the rotation power element to drive the flap to perform various deflection movements, and detect the deflection angle and temperature data in real time to ensure the stable operation of the flap drive system; Evaluate the test results, and gradually make the flap results match the expected goals by repeatedly and finely adjusting the load and the flap control signal.

[0060] As a further optimization scheme, in this embodiment, the speed, direction of the rotation power element 5 and the amplitude, duty cycle, and frequency ratio of the disable signal in the single-frequency signal are 2:1:2, the speed, direction of the rotation power element 5 and the amplitude, duty cycle, and frequency ratio of the disable signal in the mixed-frequency signal are 4:1:4, and the speed, direction of the rotation power element 5 and the amplitude, duty cycle, and frequency ratio of the disable signal in the step signal are 2:1:2.

[0061] Editing of the single-frequency signal for the flap 9 deflection movement, such as Figure 8as shown in (a), (b), (c), and (d) therein. The single-frequency and single-period deflection of the flap 9 is as follows Figure 7 shown. The deflection movement process of the flap 9 is: equilibrium position OK - deflected upward to the designed angle OH - restored to the equilibrium position OK under the action of the spring - deflected downward to the designed angle ON - restored to the equilibrium position OK under the action of the spring. Therefore, different frequency 0-5V square wave voltage signals need to be sent to the rotational speed, direction, and disable three function ports of the single-quadrant controller. Since the direction when the flap 9 deflects upward or downward is on the same side as the direction when it is restored, the frequency of the voltage signal for controlling the direction is 1 / 2 of the speed and disable signals. Only when the flap 9 deflects from the equilibrium position to the limit position, speed and start signals are sent to the single-quadrant controller. Therefore, the speed and disable function ports of the single-quadrant controller send square wave voltage signals with the same frequency. In addition, the limit deflection angle of the flap 9 can be changed by changing the amplitude of the square wave voltage signal sent to the speed port and the duty cycle of the disable function square wave voltage signal.

[0062] The editing of the mixed-frequency signal for the deflection movement of the flap 9 is as follows Figure 8 as shown in (e), (f), (g), and (h) therein. The single-period deflection of the mixed-frequency of the flap 9 is as follows Figure 7 shown. The movement process is: equilibrium position OK - deflected upward to the designed large angle OI - restored to the equilibrium position OK under the action of the spring - deflected downward to the designed small angle OL - restored to the equilibrium position OK under the action of the spring - deflected upward to the designed small angle OJ - restored to the equilibrium position OK under the action of the spring - deflected downward to the designed large angle OM - restored to the equilibrium position OK under the action of the spring. Since the mixed-frequency movement of the flap 9 adds a small-angle movement process compared with the single-frequency movement, custom voltage square wave signal editing is required for the control signal of the speed port of the single-quadrant controller. Compared with the constant amplitude of the single-frequency speed control square wave, the voltage amplitude needs to be reduced during small-angle deflection for the mixed-frequency to achieve the expected angle. The control signal of the disable port of the single-quadrant controller still uses a square wave with the same frequency as the custom square wave of the speed control signal, and at the same time, the control signal of the direction port is also designed as a square wave with a frequency of 1 / 2 of the control signal of the disable port.

[0063] The editing of the step signal for the deflection movement of the flap 9 is as follows Figure 8 as shown in (i), (j), (k), and (l) therein. The single-period deflection of the step control of the flap 9 is as follows Figure 7As shown, the movement process is as follows: equilibrium position OK - up deviation to design angle OJ - up deviation to design angle OI - up deviation to design angle OH - recovery to angle OJ - recovery to equilibrium position OK under the action of the spring - down deviation to design angle OL - down deviation to design angle OM - down deviation to design angle ON - recovery to angle OL - recovery to equilibrium position OK under the action of the spring. The one - way deflection of the flap 9 under the control of the step signal involves changes in three angles. Therefore, when controlling with the speed signal, three different voltage signals of different gears need to be designed to correspond to it, that is, the signal form of a custom - made staircase wave is used for control. Compared with the single - frequency and mixed - frequency signals, the step signal only needs to send a disabling signal to the single - quadrant controller during the process of recovering to angle OJ or OL - recovering to the equilibrium position OK under the action of the elastic member. Therefore, the disabling control signal still uses square - wave control, and its frequency is the same as that of the speed control signal, but the low - level duty cycle, that is, the disabling duty cycle, should be the same as the duty cycle during the process of recovering to angle OJ or OL - recovering to the equilibrium position OK under the action of the elastic member. In addition, the direction - signal control port still uses square - wave control with a frequency of 1 / 2 of the frequency of the direction - control signal.

[0064] The test method in this embodiment can be applied to the scaled - down model of the helicopter blade. Before the rotor test, the aerodynamic force at each rotor speed is simulated through the load device, and various control strategies are used to drive the flap to achieve various motion modes to evaluate the reliability and stability of the flap drive system of the electric - control rotor.

[0065] The above - disclosed are only the preferred specific embodiments of the present invention. However, the embodiments of the present invention are not limited thereto, and any changes that can be thought of by those skilled in the art should fall within the protection scope of the present invention.

Claims

1. A simulated aerodynamic load test system for a flap drive system, characterized in that, Comprising: A bracket and a flap frame (8) fixedly arranged on the bracket; A flap (9), horizontally arranged on one side of the flap frame (8), the flap (9) is hinged to the flap frame (8), and the hinge axis is parallel to the length direction of the flap (9); A driving mechanism, arranged on the flap frame (8), the output end of the driving mechanism is connected to the flap (9) to drive the flap (9) to deflect around its hinge axis; A connecting rod (15), horizontally arranged at one end of the flap (9) and perpendicular to the hinge axis of the flap (9); Two elastic members (21), vertically arranged between the connecting rod (15) and the bracket, the two elastic members (21) are symmetrically arranged with respect to the center line of the hinge axis of the flap (9), one end of the elastic member (21) is connected to the bracket, and the other end is slidably connected to it along the length direction of the connecting rod (15). Symmetrically move the two elastic members (21) along the length direction of the connecting rod (15), and lock the positions of the elastic members (21) through locking members to change the load applied to the flap (9).

2. The simulated aerodynamic load test system for the flap drive system according to claim 1, characterized in that One end of the flap (9) is horizontally and fixedly provided with a shaft accessory (16), the shaft accessory (16) is coaxial with the center line of the hinge axis of the flap (9), the connecting rod (15) horizontally passes through the shaft accessory (16) and is fixedly connected to it, and the other end of the shaft accessory (16) is rotatably connected to the bracket around its circumference.

3. The simulated aerodynamic load test system for the flap drive system according to claim 1, characterized in that The locking member includes: two pairs of locking nuts (17), the two pairs of locking nuts (17) are sleeved on the connecting rod (15) and threadedly connected to it, one end of the elastic member (21) away from the bracket is sleeved on the connecting rod (15), and the two locking nuts (17) of each pair are located on both sides of the elastic member (21) and respectively abut against it.

4. The simulated aerodynamic load test system for the flap drive system according to claim 1, characterized in that, The driving mechanism includes: a rotary power element (5), a rocker arm (6) and an eccentric wheel (7), the rotary power element (5) is fixedly arranged on the flap frame (8), the eccentric wheel (7) is coaxially fixedly arranged on the output shaft of the rotary power element (5), one end of the rocker arm (6) is sleeved on the eccentric shaft of the eccentric wheel (7), the eccentric shaft is rotatably connected to the rocker arm (6) around its circumference, and the other end of the rocker arm (6) is hinged to the flap (9).

5. The simulated aerodynamic load test system for a flap drive system according to claim 4, characterized in that, Further comprising: A single - quadrant controller, the single - quadrant controller is signal - connected to the rotary power element (5) to output a control signal to make the rotary power element (5) drive the flap (9) to deflect.

6. The simulated aerodynamic load test system for a flap drive system according to claim 5, wherein, A temperature sensor (4) is fixedly arranged on the rotary power element (5), and an angle sensor (10) is fixedly arranged on the hinge axis of the flap (9).

7. A method for simulating aerodynamic load testing of a flap drive system, characterized in that, An analog aerodynamic load test system for the flap drive system according to claim 6, the test method comprising the following steps: S1. Symmetrically move the two elastic members (21) to adjust the load applied by the elastic members (21) to the flap (9); S2. Control the rotary power element (5) to drive the flap (9) to perform a deflection motion; S3. Collect the flap deflection angle information through the angle sensor (10), draw the flap deflection motion curve according to the deflection angle information, collect the temperature information of the rotary power element (5) through the temperature sensor (4), and draw the temperature change curve of the rotary power element (5) according to the temperature information; S4. Compare whether the flap deflection motion curve conforms to the flap deflection motion curve at the designed rotor speed and observe whether the temperature change curve of the rotary power element (5) is within the safe operating temperature range. If the flap deflection motion curve conforms to the flap deflection motion curve at the designed rotor speed and the temperature change curve of the rotary power element (5) is within the safe operating temperature range, stop the test. If not, adjust the load applied to the flap (9) and repeat the above steps S2 - S4 until the flap deflection motion curve conforms to the flap deflection motion curve at the designed rotor speed and the temperature change curve of the rotary power element (5) is within the safe operating temperature range.

8. The method for simulating aerodynamic load test of a flap drive system according to claim 7, characterized in that, The control signals for controlling the rotary power element (5) include: single - frequency signals, mixed - frequency signals, and step signals, which are obtained by editing the speed, direction, and the frequency, amplitude, and duty cycle of the disable signal of the rotary power element (5).

9. The method for simulating aerodynamic load test of the flap drive system according to claim 8, wherein In the single - frequency signal, the ratio of the speed, direction, and the amplitude, duty cycle, and frequency of the disable signal of the rotary power element (5) is 2:1:

2. In the mixed - frequency signal, the ratio of the speed, direction, and the amplitude, duty cycle, and frequency of the disable signal of the rotary power element (5) is 4:1:

4. In the step signal, the ratio of the speed, direction, and the amplitude, duty cycle, and frequency of the disable signal of the rotary power element (5) is 2:1:2.

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