Simulation aerodynamic load test system and test method of flap drive system

Abstract

The application relates to a simulation aerodynamic load test system and test method of a flap driving system, belonging to the technical field of rotors, which comprises a support and a flap support fixed on the support, a flap horizontally arranged on one side of the flap support, a driving mechanism arranged on the flap support, an output end of the driving mechanism connected with the flap, a connecting rod horizontally arranged on one end of the flap, two elastic members vertically arranged between the connecting rod and the support, one end of the elastic member connected with the support, and the other end slidingly connected with the connecting rod along the length direction of the connecting rod, the driving mechanism drives the flap to perform up-down deflection movement, the load inertia of the actual flap driving system inside the blade can be simulated, the load test effect of the flap driving system is improved, the two elastic members in symmetrical distribution and adjustable are used to change the load applied to the flap, various sizes of loads are provided for the up-down deflection of the flap, and 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 in particular relates to a simulated aerodynamic load test system and a test method for a flap drive system. Background Art

[0002] Traditional helicopters primarily use automatic tilting mechanisms to adjust blade pitch. With the rapid development of modern electronic and electrical technologies, advanced materials, and rotor design and manufacturing techniques, foreign countries have developed an electric rotor control technology, combining it with a trailing-edge servo flap system. This system uses an electric actuator embedded within the blade or at the hub to drive the flaps through a lever system, generating a pitching moment about the blade pitch axis, ultimately changing the blade pitch. This control method offers several advantages over traditional helicopter rotor control systems: The electric rotor control system eliminates the automatic tilting mechanism, mechanical control levers, and hydraulic equipment, significantly improving the helicopter's weight efficiency and enhancing its reliability, maintainability, and safety. The elimination of the automatic tilting mechanism and mechanical lever system reduces hub drag and improves overall aerodynamic efficiency. Furthermore, incorporating high-order harmonic control into the flap control effectively reduces blade noise and vibration. It can be seen that the electronically controlled rotor is the product of the combination of the evolution of traditional technology and the application of the latest technology. Its unique modern features and many advantages determine that the electronically controlled rotor system has a bright application prospect and represents the development direction of the new generation of rotors.

[0003] During the development of electronically controlled rotor blades, preliminary verification of the flap drive system is essential. By installing a load device at the flap end to simulate aerodynamic forces, an actuator control scheme is designed to observe whether the flap drive system operates optimally under different control modes when the flap is loaded. Evaluating the flap drive system's performance before formal rotor testing improves reliability during formal rotor testing. This also ensures that timely adjustments to the flap drive system's design are made when the expected results do not match those of the preliminary verification, shortening the rotor development cycle.

[0004] Currently, existing methods for load testing flap drive systems in the field of electronically controlled rotors include: directly applying a simulated aerodynamic load at the actuator shaft end or using flexible beams and springs to apply a simulated aerodynamic load at the designed rotor speed.

[0005] The first method directly applies a simulated aerodynamic load at the designed rotor speed to the actuator shaft, then uses a Hall effect sensor to collect the motor deflection angle signal. Because flap actuation in electronically controlled rotors requires consideration of the internal space within the blades, indirect actuation is often used. Failure to account for the load inertia of the rod system during testing can affect flap deflection during subsequent rotor testing.

[0006] The second method is to 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 load at other rotor speeds, the flexible beam needs to be replaced, making the load test of the flap drive system more complicated.

[0007] The third method uses a high-power actuator. Since the inertia of the flap drive rod system has little effect on the actuator's power output, the load inertia of the rod system can be ignored. The existing technology arranges four springs in a cross structure at the output shaft end of the high-power actuator to simulate aerodynamic loads, and detects the actuator's deflection angle through an angle sensor. However, this test method requires the spring installation position to be fixed. When simulating aerodynamic loads at other rotor speeds, the structural parameters of the spring, such as the spring length, wire diameter, material, and number of turns, need to be redesigned, making the load test of the flap drive system more complicated. Summary of the Invention

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

[0009] The technical solution of the present invention is: a simulated aerodynamic load test system for a flap drive system, comprising a bracket and a flap frame fixed on the bracket, the flap being horizontally arranged on one side of the flap frame, the flap being hinged to the flap frame, and the hinge axis and the length direction of the flap being parallel to each other, a driving mechanism being arranged on the flap frame, and the output end of the driving mechanism being connected to the flap to drive the flap to deflect around its hinge axis, a connecting rod being horizontally arranged at one end of the flap and being perpendicular to the hinge axis of the flap, two elastic members being vertically arranged between the connecting rod and the bracket, the two elastic members being symmetrically arranged about the center line of the hinge axis of the flap, one end of the elastic member being connected to the bracket, and the other end being slidably connected to the connecting rod along the length direction, the two elastic members being symmetrically moved along the length direction of the connecting rod, and the positions of the elastic members being locked by locking members to change the load applied to the flap.

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

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

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

[0013] Preferably, the driving mechanism includes: a rotating power element, a rocker arm and an eccentric wheel. The rotating power element is fixed on the flap frame, the eccentric wheel is coaxially fixed on the output shaft of the rotating power element, one end of the rocker arm is sleeved on the eccentric shaft of the eccentric wheel, the eccentric shaft is rotatably connected to the rocker arm around its circumference, and the other end of the rocker arm is hinged to the flap.

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

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

[0016] A method for testing a simulated aerodynamic load of a flap drive system is provided. The method comprises the following steps:

[0017] S1. Adjust the load applied by the elastic members to the flap by symmetrically moving the two elastic members;

[0018] S2, driving the flap to perform deflection motion by controlling the rotating power element;

[0019] S3, collecting deflection angle information of the flap through an angle sensor, drawing a deflection motion curve of the flap according to the deflection angle information, collecting temperature information of the rotating power element through a temperature sensor, and drawing a temperature change curve of the rotating power element according to the temperature information;

[0020] S4. Compare the deflection motion curve of the flap to see whether it is consistent with the deflection motion curve of the flap at the rotor design speed, and observe whether the temperature change curve of the rotating power element is within the safe operating temperature range. If the deflection motion curve of the flap is consistent with the deflection motion curve of the flap at the rotor design speed, and the temperature change curve of the rotating power element is within the safe operating temperature range, stop the test; if not, adjust the load applied to the flap, and repeat the above steps S2-S4 until the deflection motion curve of the flap is consistent with the deflection motion curve of the flap at the rotor design speed, and the temperature change curve of the rotating power element is within the safe operating temperature range.

[0021] Preferably, the control signal for controlling the rotating power element includes: a single frequency signal, a mixed frequency signal and a step signal, and the single frequency signal, the mixed frequency signal and the step signal are obtained by editing the speed, direction and frequency, amplitude and duty cycle of the rotating power element.

[0022] Preferably, the speed, direction, amplitude, duty cycle, and frequency ratio of the rotating power element in the single-frequency signal and the disable signal are 2:1:2; the speed, direction, amplitude, duty cycle, and frequency ratio of the rotating power element in the mixed signal and the disable signal are 4:1:4; and the speed, direction, amplitude, duty cycle, and frequency ratio of the rotating power element in the step signal and the disable signal are 2:1:2.

[0023] Compared with the prior art, the present invention provides a simulated aerodynamic load test system and test method for a flap drive system. Through the coordinated use of a bracket, a flap frame, a flap, a drive mechanism, a connecting rod and an elastic member, the drive mechanism drives the flap to perform an up and down deflection movement on the flap frame, which can simulate the load inertia of the actual flap drive system inside the blade, thereby improving the load test effect of the flap drive system. The two symmetrically distributed and adjustable elastic members on the connecting rod can be used to change the load applied to the flap, thereby providing 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. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 is a flow chart of the load testing method of the present invention;

[0025] Figure 2 It is an overall diagram of the load testing system of the present invention;

[0026] Figure 3 is a perspective view of the load testing system of the present invention;

[0027] Figure 4 is a top view of the load testing system of the present invention;

[0028] Figure 5 This is a simplified diagram of the flap drive structure of the present invention;

[0029] Figure 6 It is the design principle diagram of the four-bar mechanism of the present invention;

[0030] Figure 7 is a schematic diagram of flap deflection of the present invention;

[0031] Figure 8 1 is a diagram of the single-frequency, mixed-frequency and step motion control signals of the flap of the present invention, wherein (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 disable 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 disable 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, and (l) is the step motion disable control of the flap.

[0032] Description of reference numerals:

[0033] 1. Load fixing table; 2. Bench vise; 3. Motor housing; 4. Temperature sensor; 5. Rotating 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 attachment; 17. Lock nut; 18. Fixed angle piece; 19. Experimental table; 21. Elastic part. DETAILED DESCRIPTION

[0034] The present invention provides a flap drive system simulation aerodynamic load test system and test method, the following is combined with Figures 1 to 8 The present invention is described with reference to a structural schematic diagram of FIG.

[0035] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "axial", "radial", "circumferential" and the like to indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the technical solutions 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 understood as limiting the present invention.

[0036] Figure 3 is a three-dimensional diagram of the load testing system of this embodiment, as shown in FIG. Figure 3 As shown, a simulated aerodynamic load test system for a flap drive system includes a bracket and a flap frame 8 fixed 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 and the length direction of the flap 9 are parallel to each other, the driving mechanism is 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, 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 about 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 the connecting rod 15 along the length direction, the two elastic members 21 are symmetrically moved along the length direction of the connecting rod 15, and the position of the elastic member 21 is locked by a locking member to change the load applied to the flap 9.

[0037] 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 driving mechanism on the flap frame 8 to drive the flap 9 to deflect up and down, thereby simulating the load inertia of the actual flap drive system inside the blade, avoiding affecting the flap deflection effect during the later rotor experiment, and then using the two symmetrically distributed and adjustable elastic members 21 on the connecting rod 15. The elastic members 21 are symmetrically distributed on the connecting rod 15, which can ensure that the load torque provided for the up and down deflection of the flap 9 is 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, and various sizes of loads can be provided for the up and down deflection of the flap, thereby simulating the aerodynamic torque at the flap at the rotor design speed, effectively improving the convenience of the flap drive system load test.

[0038] In this embodiment, a flap hinge frame 11 can be provided on the side of the flap 9 close to the flap frame. The flap hinge frame 11 is hinged to the flap frame 8 , wherein the flap hinge frame 11 and the flap 9 are assembled and fixedly connected by a high-strength adhesive.

[0039] In this embodiment, the bracket includes a load fixing platform 1, an L-shaped angle piece 13 and a fixed angle piece 18. Symmetrical countersunk grooves are provided on the load fixing platform 1. The two countersunk grooves are located on both sides of the flap 9 and are parallel to its length direction. Fixed angle pieces 18 are respectively provided on the countersunk grooves near the connecting rod 15. The fixed angle piece 18 is fixedly connected to the load fixing platform 1 by bolts 14. The elastic member 21 is connected to the fixed angle piece 18 at one end away from the connecting rod 15. The elastic member 21 adopts a tension spring. The elastic member 21 is stretched to a certain length during installation and then installed to prevent the inherent length of the elastic member 21 from affecting the normal deflection of the flap 9 during compression. Two L-shaped angle pieces 13 are provided on the countersunk grooves near the side of the flap frame 8. The L-shaped angle piece 13 is fixedly connected to the load fixing platform 1 by bolts 14. The flap frame 8 is respectively fixedly connected to the vertical ends of the L-shaped angle piece 13. The positions of the L-shaped angle piece 13 and the fixed angle piece 18 can be adjusted through the countersunk grooves, which is convenient for reuse when the size of the flap and the drive mechanism changes.

[0040] Figure 2 This is the overall diagram of the load testing system of this embodiment, as shown in Figure 2 As shown, in order to reduce the high-frequency vibration generated when the flap drive system is in operation, the load fixing platform 1 is made of 45 steel and is fixed to the experimental table 19 by two vises 2, thereby reducing the impact of the vibration generated when the flap drive system is in operation on the test results.

[0041] As a further optimization scheme, in this embodiment, an axis attachment 16 is horizontally fixed to one end of the flap 9, and the axis attachment 16 is coaxial with the center line of the hinge axis of the flap 9. The connecting rod 15 passes horizontally through the axis attachment 16 and is fixedly connected to it. The other end of the axis attachment 16 is rotatably connected to the bracket around its circumference.

[0042] In this embodiment, the shaft attachment 16 cooperates with the elastic member 21 to apply a load to the flap 9. The shaft attachment 16 is rotatably connected to the bracket so that when the flap 9 deflects up and down, the shaft attachment 16 can rotate synchronously, thereby improving the stability of applying the load to the flap 9.

[0043] Specifically, the connecting rod 15 passes through the shaft attachment 16, and the two ends of the connecting rod 15 are symmetrical about the center line of the shaft attachment 16. The connecting rod 15 is fixedly connected to the shaft attachment 16 by screws to prevent loosening due to vibration during the movement of the connecting rod 15 and the shaft attachment 16 during the test process.

[0044] As a further optimization solution, the locking part in this embodiment 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, and the end of the elastic part 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 part 21 and respectively abut against it.

[0045] In this embodiment, the connecting rod 15 is a threaded rod. After the two elastic members 21 are symmetrically moved along the length direction of the connecting rod 15 and the load applied to the flap 9 is changed, the position of the elastic member 21 is fixed by cooperating with the two locking nuts 17 and the threaded rod, so that the load applied to the flap 9 remains stable.

[0046] Figure 4 This is a top view of the load testing system of this embodiment. Figure 4 As shown, as a further optimization scheme, a specific structure of a driving mechanism is given in this embodiment, and the driving mechanism includes: a rotating power element 5, a rocker arm 6 and an eccentric wheel 7. The rotating power element 5 is fixed on the flap frame 8, and the eccentric wheel 7 is coaxially fixed on the output shaft of the rotating power element 5. One end of the rocker arm 6 is sleeved on the eccentric shaft of the eccentric wheel 7, and 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.

[0047] In this embodiment, the rotating power element 5 of the driving mechanism adopts a brushless DC motor, which cooperates with the rocker arm 6 and the eccentric wheel 7 to realize large-angle deflection of the flap 9 and meet the requirements for flap deflection angle under high rotor speed conditions.

[0048] Specifically, one end of the rocker arm 6 away from the eccentric wheel 7 is hinged to the flap hinge frame 11, and the hinge axis between the rocker arm 6 and the flap hinge frame 11 and the hinge axis center line between the flap hinge frame 11 and the flap frame 8 are parallel to each other and not coaxial.

[0049] The transmission principle of the drive mechanism is as follows Figure 5 As shown, it can be simplified into a planar four-bar mechanism, with the first connecting rod position CO, the frame position OA, the second connecting rod position BA, and the connecting rod position BC. The four-bar mechanism is designed according to the predetermined angular displacement of the first and second connecting rods. First, the dimensions of the first connecting rod and the frame, as well as the preset deflection angles of the first and second connecting rods, are determined based on the designed airfoil dimensions, as shown in FIG. Figure 6 As shown, it is stipulated that the flap upward deflection is positive, the position CO of the first connecting rod corresponds to the flap not deflected, the position C1O of the first connecting rod corresponds to the flap downward deflection, and the position C2O of the first connecting rod corresponds to the flap upward deflection. Connect points C1 and C2 to point A respectively, and use point A as the center of the circle, C1A and C2A as the radii, and draw an arc at a preset negative angle according to the position BA of the second connecting rod 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 size of the four-bar, and convert the deflection of the first connecting rod into the deflection of the second connecting rod, that is, realize the deflection of the rotating power element 5 to the flap 9.

[0050] When the rotor rotates, centrifugal force affects the flap drive system embedded in the blades. Therefore, there are two eccentric wheels 7, the eccentric shafts of the two eccentric wheels 7 are coaxially fixedly connected, and the rocker arm 6 is sleeved on the eccentric shafts of the two eccentric wheels 7. One eccentric wheel 7 is coaxially fixedly connected to the output shaft of the rotating power element 5, and the other eccentric wheel 7 is rotatably connected to the flap frame 8. In addition, thrust ball bearings 12 are installed at the hinge of the rocker arm 6 and the flap hinge joint frame 11, as well as at the connection between the eccentric wheel 7 and the flap frame 8, to reduce the impact of centrifugal force on the flap drive system.

[0051] When the rotor is operating at high speed, the flap drive system will operate in a strong and complex aerodynamic field, which requires the drive mechanism to have sufficient strength to meet the working requirements. Therefore, the material of the drive mechanism's rotating power element 5, rocker arm 6 and eccentric wheel 7 is made of hard aluminum alloy.

[0052] The temperature control of the rotating power element 5 in the driving mechanism of the aforementioned 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 small and the heat dissipation is poor. If the operating temperature of the rotating power element 5 cannot be controlled, the motor power may be reduced or damaged.

[0053] Therefore, in this embodiment, when the rotating power element 5 is installed on the flap frame 8, the motor cover 3 is installed on the outside of the rotating power element 5, and the motor cover 3 is fixedly connected to the flap frame 8. The material of the motor cover 3 is aluminum alloy. The heat generated by the operation of the rotating power element 5 is transferred to the flap frame 8 through the motor cover 3, and the rotating power element 5 is dissipated. The heat is thereby cooled.

[0054] In addition, in the above embodiment, a layer of thermal conductive glue is applied on the contact surface between the motor housing 3 and the flap frame 8 to improve the efficiency of heat transfer from the motor housing 3 to the flap frame 8, further improving the cooling effect on the rotating power element 5.

[0055] As a further optimization solution, this embodiment also includes: a single-quadrant controller, which is signal-connected to the rotating power element 5 to output a control signal to enable the rotating power element 5 to drive the flap 9 to deflect.

[0056] In this embodiment, a single-quadrant controller is used to receive voltage signals to control the speed, direction, and start and stop of the power output of the rotating power element 5. The principle of this method for controlling the rotating power element 5 is as follows: after the rotating power element 5 drives the flap 9 to deflect upward to the design angle, a disable command is sent to the rotating power element 5. At this time, the flap 9 decelerates to a stop and moves in the opposite direction to return to the equilibrium position under the action of the symmetrical torque of the elastic member 21. Then, a start and reversing command is sent to the rotating power element 5. After the flap 9 deflects in the opposite direction to the design angle, it is disabled again, and then returns to the equilibrium position again under the action of the symmetrical balancing torque of the elastic member 21. The above is a periodic deflection motion process of the flap 9 driven by the rotating power element 5.

[0057] At the same time, the disable function of the single-quadrant controller is utilized and high and low level control is adopted to prevent the rotating power element 5 from continuously running and causing the temperature to gradually increase, resulting in a decrease in output power or damage, so that the temperature of the rotating power element 5 is controlled below a safe temperature.

[0058] As a further optimization solution, in this embodiment, a temperature sensor 4 is fixedly provided on the rotating power element 5 , and an angle sensor 10 is fixedly provided on the hinge shaft of the flap 9 .

[0059] In this embodiment, a temperature sensor 4 is provided on the rotating power element 5 to collect temperature information of the rotating power element 5 , and an angle sensor 10 is provided on the hinge shaft of the flap 9 to collect angle information of the up and down deflection of the flap 9 .

[0060] Specifically, temperature sensor 4 consists of a platinum resistance chip sensor and a voltage transmitter. The platinum resistance sensor is attached to the body of rotating power element 5. As rotating power element 5 operates and its body temperature gradually rises, temperature sensor 4 converts the temperature variable into a resistance variable, which is then converted into a voltage variable by a voltage transmitter. Finally, the voltage signal is converted into a temperature variable by an acquisition card and a host computer, and displayed.

[0061] Specifically, a voltage / angle calibrated angle sensor 10 is installed on the hinge shaft connecting the flap hinge joint 11 and the flap frame 8. When the flap 9 deflects, the hinge shaft rotates synchronously. The angle variable is converted into a voltage variable by the angle sensor 10. The voltage signal is collected by an acquisition card and finally converted into an angle variable using a calibration formula in the host computer and displayed.

[0062] Figure 1 This is a flow chart of the load testing method of this embodiment. Figure 1 As shown, a method for testing a simulated aerodynamic load of a flap drive system is provided. The method is based on a simulated aerodynamic load testing system for a flap drive system. The method comprises the following steps:

[0063] S1. Adjust the load applied by the elastic members 21 to the flap 9 by symmetrically moving the two elastic members 21;

[0064] S2, driving the flap 9 to perform deflection motion by controlling the rotating power element 5;

[0065] S3. Collecting deflection angle information of the flap 9 through the angle sensor 10, drawing a deflection motion curve of the flap 9 according to the deflection angle information, collecting temperature information of the rotating power element 5 through the temperature sensor 4, and drawing a temperature change curve of the rotating power element 5 according to the temperature information;

[0066] S4. Compare the deflection motion curve of the flap 9 to see whether it is consistent with the deflection motion curve of the flap 9 at the rotor design speed, and observe whether the temperature change curve of the rotating power element 5 is within the safe operating temperature range. If the deflection motion curve of the flap 9 is consistent with the deflection motion curve of the flap 9 at the rotor design speed, and the temperature change curve of the rotating 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 motion curve of the flap 9 is consistent with the deflection motion curve of the flap 9 at the rotor design speed, and the temperature change curve of the rotating power element 5 is within the safe operating temperature range.

[0067] The test method in this embodiment can more completely simulate the operating conditions of the entire flap drive system under load, making the results of the preliminary evaluation of the flap drive system before the rotor test more reliable.

[0068] As a further optimization solution, the control signal for controlling the rotating power element 5 in this embodiment includes: a single-frequency signal, a mixed-frequency signal and a step signal. The single-frequency signal, the mixed-frequency signal and the step signal are obtained by editing the speed, direction and frequency, amplitude and duty cycle of the rotating power element 5 and the disable signal.

[0069] The test method in this embodiment takes into account that different operating modes of the electronically controlled rotor have different requirements for the flap deflection movement, and therefore proposes three motion control signals for the flap: single frequency, mixed frequency and step. Through the single frequency signal, mixed frequency signal and step signal, the rotating power element 5 drives the flap 9 to perform corresponding single frequency, mixed frequency and step deflection movements, which can reduce the vibration and noise generated during the operation of the rotor and the operating temperature of the rotating power element 5, and prevent the output power of the rotating power element 5 from decreasing or being damaged.

[0070] In this embodiment, a single-frequency signal, a mixed-frequency signal, and a step signal are edited respectively through a function signal generator.

[0071] The aerodynamic torque at the flaps is calculated by aerodynamic simulation software when the designed rotor rotates, and the position of the elastic member 21 is adjusted to simulate the aerodynamic torque at the flaps 9 at the designed rotor speed;

[0072] The frequency of the flap 9 deflection is calculated according to the designed rotor speed, and then the rotating power element 5 drives the flap 9 to deflect through the control signal;

[0073] Single frequency signal editing:

[0074] Specifically, the load required for the single-frequency deflection motion of flap 9 is adjusted. A function signal generator is used to adjust the frequency, duty cycle, amplitude, and phase relationship of the control signal. The single-frequency control signal for flap 9 is then transmitted, causing the rotating power element 5 to drive the flap 9 for deflection. Angle sensor 10 collects waveforms of the flap angle variation over multiple cycles to observe whether the frequency and deflection amplitude meet the designed values. A temperature sensor 4 monitors the temperature of the rotating power element 5 during flap deflection to ensure it remains within the safe operating temperature range.

[0075] Mixed signal editing:

[0076] Specifically, the load required for the mixed frequency deflection movement of the flap 9 is prepared. A custom square wave signal for mixed frequency control is written using programming software, the waveform data is exported to the function signal generator host computer through Excel, and then sent to the single quadrant controller, so as to control the rotation power element 5 to drive the flap 9 to deflect. Through the angle sensor 10, the angle change waveform graph of the flap in multiple cycles is collected, whether the large angle and small angle curves of the flap 9 deflection controlled by the mixed frequency signal are periodic, symmetric, and whether there is a missing wave problem. Through the temperature sensor 4, whether the temperature of the rotation power element 5 during the deflection of the flap is within the safe use temperature standard.

[0077] Step signal editing:

[0078] Specifically, the load required for the mixed frequency deflection movement of the flap 9 is prepared. A custom square wave signal for mixed frequency control is written using programming software, the waveform data is exported to the function signal generator host computer through Excel, and then sent to the single quadrant controller, so as to control the rotation power element 5 to drive the flap 9 to deflect. Through the angle sensor 10, the angle change waveform graph of the flap in multiple cycles is collected, whether the large angle and small angle curves of the flap 9 deflection controlled by the mixed frequency signal are periodic, symmetric, and whether there is a missing wave problem. Through the temperature sensor 4, whether the temperature of the rotation power element 5 during the deflection of the flap is within the safe use temperature standard.

[0079] Compare whether the collected flap deflection movement curve and motor temperature change curve meet the expected target, if not, adjust the position of the elastic member 21, change the size of the load and ensure the symmetry of the load, at the same time, accurately adjust the voltage control signal amplitude, duty ratio and frequency, repeat the test until it meets the expected standard.

[0080] The specific test process is:

[0081] The test system is made of aluminum alloy by mechanical processing and assembled;

[0082] By symmetrically moving the positions of the two elastic members, the length of the force arm is controlled, thereby controlling the load applied to the flap;

[0083] The deflection angle of the flap is converted into voltage by the angle sensor, and the voltage signal is converted into angle signal output by the voltage / angle calibration formula through the data acquisition card and the programming software;

[0084] A platinum resistance temperature sensor patch is installed on the rotation power element, and the resistance-voltage-temperature conversion is realized through the voltage transmitter and the acquisition card, so as to detect the temperature of the rotation power element;

[0085] The flap deflection frequency is calculated based on the designed rotor speed. A function signal generator is then used to design single-frequency, mixed-frequency, and step signals to control the rotating power element to drive the flaps through various deflection movements. The deflection angle and temperature data are then monitored in real time to ensure stable operation of the flap drive system.

[0086] Evaluate the test results and gradually make the flap results consistent with the expected targets by repeatedly fine-tuning the load and flap control signals.

[0087] As a further optimization scheme, in this embodiment, the speed, direction, amplitude, duty cycle, and frequency ratio of the rotating power element 5 in the single-frequency signal and the disable signal are 2:1:2, the speed, direction, amplitude, duty cycle, and frequency ratio of the rotating power element 5 in the mixed signal and the disable signal are 4:1:4, and the speed, direction, amplitude, duty cycle, and frequency ratio of the rotating power element 5 in the step signal and the disable signal are 2:1:2.

[0088] Flap 9 deflection motion single frequency signal editing, such as Figure 8 The single-frequency single-cycle deflection of flap 9 is shown in (a), (b), (c), and (d). Figure 7 As shown, the deflection motion process of the flap 9 is: equilibrium position OK - upward deflection to the design angle OH - restoration of the equilibrium position OK under the action of the spring - downward deflection to the design angle ON - restoration of the equilibrium position OK under the action of the spring. Therefore, it is necessary to send 0-5V square wave voltage signals of different frequencies to the three functional ports of the single-quadrant controller: speed, direction, and disable. Since the direction of the flap 9 when deflecting upward or downward is on the same side as the direction when restoring, the frequency of the voltage signal for the control direction is 1 / 2 of the speed and disable signals. The speed and start signals are only sent to the single-quadrant controller when the flap 9 deflects from the equilibrium position to the extreme position. Therefore, the speed and disable function ports of the single-quadrant controller send square wave voltage signals of the same frequency. In addition, the extreme deflection angle of the flap 9 can be changed by changing the amplitude of the square wave voltage signal sent by the speed port and the duty cycle of the disable function square wave voltage signal.

[0089] Flap 9 deflection motion mixed signal editing, such as Figure 8 The mixed frequency single cycle deflection of flap 9 is shown in (e), (f), (g), and (h). Figure 7The motion process is shown as follows: balanced position OK—upward deflection to the designed large angle OI—restoration to the balanced position OK under the action of the spring—downward deflection to the designed small angle OL—restoration to the balanced position OK under the action of the spring—upward deflection to the designed small angle OJ—restoration to the balanced position OK under the action of the spring—downward deflection to the designed large angle OM—restoration to the balanced position OK under the action of the spring. Since the mixed frequency motion of the flap 9 adds the small angle motion process compared with the single frequency motion, the control signal of the speed port of the single quadrant controller needs to be edited as a self-defined voltage square wave signal. Compared with the constant amplitude of the single frequency speed control square wave, the mixed frequency needs to reduce the voltage amplitude to achieve the expected angle when the small angle deflection is needed. The control signal of the disable port of the single quadrant controller still adopts the square wave with the same frequency as the self-defined square wave of the speed control signal, and the control signal of the direction port is also designed as the square wave with the frequency of 1 / 2 of the control signal of the disable port.

[0090] The deflection motion step signal of the flap 9 is edited as shown in (i), (j), (k) and (l) in FIG. 6. Figure 8 The single period deflection of the flap 9 under the step control is shown in FIG. 7. Figure 7 The motion process is shown as follows: balanced position OK—upward deflection to the designed large angle OI—restoration to the balanced position OK under the action of the spring—downward deflection to the designed small angle OL—restoration to the balanced position OK under the action of the spring—upward deflection to the designed small angle OJ—restoration to the balanced position OK under the action of the spring—downward deflection to the designed large angle OM—restoration to the balanced position OK under the action of the spring. Since the mixed frequency motion of the flap 9 adds the small angle motion process compared with the single frequency motion, the control signal of the speed port of the single quadrant controller needs to be edited as a self-defined voltage square wave signal. Compared with the constant amplitude of the single frequency speed control square wave, the mixed frequency needs to reduce the voltage amplitude to achieve the expected angle when the small angle deflection is needed. The control signal of the disable port of the single quadrant controller still adopts the square wave with the same frequency as the self-defined square wave of the speed control signal, and the control signal of the direction port is also designed as the square wave with the frequency of 1 / 2 of the control signal of the disable port.

[0091] The test method in the embodiment can be applied to a scaled model of a helicopter blade, and before the rotor test, the aerodynamic force under each rotor speed is simulated by a load device, and various control strategies are adopted to drive the flap to realize various motion modes, so as to evaluate the reliability and stability of the flap driving system of the electric control rotor.

[0092] The above disclosure is only the preferred embodiment of the present application, but the embodiments of the present application are not limited thereto, and any changes that can be thought of by those skilled in the art shall fall within the protection scope of the present application.

Claims

1. A simulated aerodynamic load test system for a flap drive system, characterized in that: include: A bracket and a flap frame (8) fixed on the bracket; A 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 and the length direction of the flap (9) are parallel to each other; A driving mechanism is arranged on the flap frame (8), and an 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) 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, and the two elastic members (21) are symmetrically arranged about 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 the connecting rod (15) along the length direction thereof. The two elastic members (21) are symmetrically moved along the length direction of the connecting rod (15), and the position of the elastic member (21) is locked by a locking member to change the load applied to the flap (9); One end of the flap (9) is fixedly provided with a shaft attachment (16) horizontally, the shaft attachment (16) is coaxial with the center line of the hinge axis of the flap (9), the connecting rod (15) passes through the shaft attachment (16) horizontally and is fixedly connected to the shaft attachment (16), and the other end of the shaft attachment (16) is rotatably connected to the bracket around its circumference; The locking member comprises: two pairs of locking nuts (17), the two pairs of locking nuts (17) being sleeved on the connecting rod (15) and being threadedly connected thereto, the elastic member (21) being sleeved on the connecting rod (15) at one end away from the bracket, the two locking nuts (17) of each pair being located on both sides of the elastic member (21) and respectively abutting against it; The driving mechanism comprises: a rotating power element (5), a rocker arm (6) and an eccentric wheel (7); the rotating power element (5) is fixed on a flap frame (8); the eccentric wheel (7) is coaxially fixed on an output shaft of the rotating power element (5); one end of the rocker arm (6) is sleeved on an 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).

2. The simulated aerodynamic load test system for a flap drive system according to claim 1, characterized in that: Also includes: A single-quadrant controller is connected to the rotating power element (5) signal to output a control signal to cause the rotating power element (5) to drive the flap (9) to deflect.

3. The simulated aerodynamic load test system for a flap drive system according to claim 2, characterized in that: A temperature sensor (4) is fixedly provided on the rotating power element (5), and an angle sensor (10) is fixedly provided on the hinge shaft of the flap (9).

4. The test method of the simulated aerodynamic load test system of the flap drive system according to claim 3, characterized in that: The following steps are involved: By symmetrically moving the two elastic members (21), the load applied by the elastic members (21) to the flap (9) is adjusted; The flap (9) is driven to perform a deflection movement by controlling the rotating power element (5); collecting deflection angle information of the flap (9) through an angle sensor (10), and drawing a deflection motion curve of the flap (9) based on the deflection angle information; collecting temperature information of the rotating power element (5) through a temperature sensor (4), and drawing a temperature change curve of the rotating power element (5) based on the temperature information; Compare the deflection motion curve of the flap (9) to see if it is consistent with the deflection motion curve of the flap (9) at the rotor design speed and observe whether the temperature change curve of the rotating power element (5) is within the safe operating temperature range. If it is consistent, stop the test; if it is not consistent, adjust the load applied to the flap (9) and repeat the above process until it is consistent.

5. The test method of the simulated aerodynamic load test system of the flap drive system according to claim 4, characterized in that: The control signal for controlling the rotating power element (5) includes: a single-frequency signal, a mixed-frequency signal and a step signal, wherein the single-frequency signal, the mixed-frequency signal and the step signal are obtained by editing the speed and direction of the rotating power element (5) and the frequency, amplitude and duty cycle of the disable signal.

6. The test method of the simulated aerodynamic load test system of the flap drive system according to claim 5, characterized in that: The speed, direction, amplitude, duty cycle, and frequency ratio of the rotating power element (5) in the single-frequency signal and the disable signal are 2:1:2, the speed, direction, amplitude, duty cycle, and frequency ratio of the rotating power element (5) in the mixed-frequency signal and the disable signal are 4:1:4, and the speed, direction, amplitude, duty cycle, and frequency ratio of the rotating power element (5) in the step signal and the disable signal are 2:1:2.

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