Testing device and testing method for large-attack-angle wind tunnel virtual flight test

Abstract

The invention provides a test device and a test method for a virtual flight test of a large-attack-angle wind tunnel, and the device comprises a mechanism supporting rod, a supporting rod control motor is fixed on the mechanism supporting rod, a belly supporting rod is fixed on the supporting rod control motor, and the belly supporting rod is driven by the supporting rod control motor to carry out attack angle self-adaptive compensation motion; the wind tunnel test model is fixed on the abdominal support pole, an airborne angle sensor is arranged in the wind tunnel test model, and the pole control motor and the airborne angle sensor are connected with the test measurement and control computer. In the wind tunnel virtual flight test process, the abdominal support can be adaptively adjusted according to the current attack angle condition of the test model, a dynamic mechanism with the large attack angle dynamic test capacity is achieved, the normal force of the test model is transmitted to the radial direction of the supporting rod control motor, and the normal load of the wind tunnel model is far larger than the axial load. Therefore, the torque requirement of the strut control motor is reduced, the size of the motor is reduced, and pneumatic interference generated thereby is reduced.

Description

Technical Field

[0001] The invention relates to the technical field of aircraft wind tunnel virtual flight tests, and in particular to a test device and a test method for a large-angle-of-attack wind tunnel virtual flight test. Background Art

[0002] Wind tunnel virtual flight test generally refers to a test method in which one or several degrees of freedom of an aircraft are released and then tested in a wind tunnel. These include typical three-degree-of-freedom virtual flight tests achieved through three-degree-of-freedom rotating hinges and wind tunnel free flight tests with six degrees of freedom released. This test method is classified as a wind tunnel dynamic test. Unlike a forced dynamic test, a wind tunnel virtual flight test mainly refers to a free dynamic test of an aircraft model. It is often used in the research of aircraft control surface excitation response, flight control rate verification, flight parameter identification and other fields. It is a comprehensive test method that integrates multiple disciplines such as aerodynamics, flight mechanics and flight control.

[0003] In recent years, traditional test methods for aircraft are increasingly unable to meet the needs of high-angle-of-attack and high-maneuver dynamic testing. In particular, the high-angle-of-attack aerodynamic data obtained by static force measurement can no longer be used to accurately evaluate the high-angle-of-attack dynamic characteristics of aircraft during flight. Although the forced dynamic test method can simulate different motion states of the aircraft, its core idea is to drive the model to move according to a pre-designed trajectory posture through a mechanism. It can be seen that the motion studied by this method is actually inconsistent with the actual motion of the aircraft. The above research methods only consider the static or dynamic aerodynamic characteristics of the model. Although aerodynamic modeling can be studied to a certain extent, there is a lack of research on flight mechanics and flight control that affect the dynamic characteristics of the aircraft. Therefore, the virtual flight test method that integrates aerodynamics, flight mechanics and flight control should have inherent advantages in the field of wind tunnel high-angle-of-attack dynamic testing.

[0004] At present, the traditional wind tunnel virtual flight test is still unable to carry out dynamic tests with large angles of attack. The reasons are as follows: First, the virtual flight with three degrees of freedom currently only relies on the three-degree-of-freedom hinge support device inside the model. Although this device can release the three degrees of freedom of the model, the travel range of each degree of freedom is limited. For example, when the model adopts abdominal support, the abdominal support rod will pass through the hole in the abdomen of the model and connect with the internal three-degree-of-freedom hinge. When the model's attitude angle is too large, the abdominal support rod will collide with the hole, thereby limiting the attitude angle range. Secondly, if the free flight test method with six degrees of freedom is adopted, although the model is free of the constraints of the abdominal support rod, it increases the constraints of the wind tunnel wall. Even if the test is carried out in a 6m*8m test section, the flight tolerance rate of releasing all degrees of freedom is still very low, and a large range of maneuvers cannot be carried out. For example, when the model quickly pulls up the angle of attack, it is inevitably accompanied by a rapid increase in flight altitude, and the model will collide with the upper wall of the wind tunnel in a very short time. In addition, in response to the problem of limited test angles, there are currently reports on the use of scimitar mechanisms for angle of attack motion compensation. This scheme adds a scimitar mechanism that can change the angle of attack of the belly support on the basis of the traditional three-degree-of-freedom mechanism. It can be understood that the model can change the angle of attack at any time with the help of the scimitar, but the followability is poor and it belongs to a quasi-static scheme. It cannot achieve dynamic compensation, so it is still impossible to carry out dynamic high-angle virtual flight tests, such as cobra maneuver simulation. Summary of the invention

[0005] The purpose of the present invention is to provide a test device and a test method for a large-angle-of-attack wind tunnel virtual flight test, which can realize a dynamic virtual flight test at a large angle of attack in a wind tunnel.

[0006] According to one purpose of the present invention, the present invention provides a test device for large angle of attack wind tunnel virtual flight test, including a mechanism support strut, a belly support strut, a strut control motor, a test measurement and control computer, an airborne angle sensor and a wind tunnel test model, the strut control motor is fixed to the mechanism support strut, the belly support strut is fixed to the strut control motor, and the belly support strut performs attack angle adaptive compensation movement under the drive of the strut control motor; the wind tunnel test model is fixed to the belly support strut, an airborne angle sensor is provided inside the wind tunnel test model, and the strut control motor and the airborne angle sensor are connected to the test measurement and control computer.

[0007] Furthermore, a three-degree-of-freedom hinge device is fixed on the wind tunnel test model, and the three-degree-of-freedom hinge device is connected to the abdominal support strut.

[0008] Furthermore, the airborne angle sensor is connected to the test measurement and control computer via a sensor communication cable.

[0009] Furthermore, the support rod control motor is connected to the test measurement and control computer via a motor communication cable.

[0010] Furthermore, the airborne angle sensor is an attitude angle sensor.

[0011] Furthermore, the belly support strut is driven by the strut control motor to follow the change of the angle of attack of the wind tunnel test model.

[0012] Furthermore, when the angle of attack of the wind tunnel test model increases, the belly support strut also rotates clockwise along with the wind tunnel test model; when the angle of attack of the wind tunnel test model decreases, the belly support strut rotates counterclockwise along with the wind tunnel test model, so that the belly support strut and the axis of the wind tunnel test model are always in an approximately vertical state, thereby avoiding interference and collision between the belly support strut and the fuselage of the wind tunnel test model.

[0013] According to another object of the present invention, the present invention provides a test method for the test device for high angle of attack wind tunnel virtual flight test, comprising the following steps:

[0014] S1. The bottom of the mechanism support rod is fixed on the wind tunnel floor, and the other end of the mechanism support rod is used to fix the rod control motor. The output end of the rod control motor is connected to the belly support rod, and the top of the belly support rod is connected to the three-degree-of-freedom hinge mechanism inside the wind tunnel test model; the wind tunnel test model is supported by the belly support rod to rotate freely around three degrees of freedom, and an airborne angle sensor for measuring the attitude angle is arranged inside the wind tunnel test model;

[0015] S2. During the test, the onboard angle sensor located inside the wind tunnel test model measures the pitch angle of the model in real time, and the pitch angle is transmitted to the test measurement and control computer. The test measurement and control computer generates a motor control signal according to the corresponding motor control algorithm and sends it to the strut control motor, thereby realizing that the strut control motor drives the abdominal support strut to follow the model's attitude angle movement.

[0016] Furthermore, a first-order inertia link is added between the target angle controlled by the support rod control motor and the angle measured by the attitude angle sensor onboard, so as to increase the stability of the motor control when the angle sensor has large noise or the attitude angle oscillates rapidly.

[0017] Furthermore, the model pitch angle variation collected by the airborne angle sensor is Δθ model To ensure that the belly support rod is always perpendicular to the axis of the model body, the rotation control target angle of the support rod control motor should also be Δθ model After adding the first-order inertia link, the actual control target angle of the strut control motor becomes Δθ model ×G(s), where G(s) is the first-order system transfer function In the formula, the time constant T needs to be adjusted according to the test conditions. The smaller it is, the faster the abdominal support rod follows, and vice versa, the larger it is, the slower it follows.

[0018] The technical solution of the present invention can adaptively adjust the belly support according to the current angle of attack of the test model during the virtual flight test in the wind tunnel, thereby realizing a dynamic mechanism with the ability of large angle of attack dynamic test, and transmitting the normal force of the test model to the radial direction of the strut control motor, while the output torque of the strut control motor is mainly used to overcome the axial load of the test model. Considering that the normal load of the wind tunnel model is much larger than the axial load, the torque demand of the strut control motor is reduced, thereby reducing the size of the motor and reducing the resulting aerodynamic interference. In addition, by setting a reasonable motor control algorithm, the soft adaptive follow-up of the belly support strut is realized, ensuring the smooth movement of the model during the test. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] In order to more clearly illustrate the specific implementation methods of the present invention or the technical solutions in the prior art, the drawings required for use in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some implementation methods of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0020] Figure 1 This is a schematic diagram of the planar structure of an embodiment of the present invention;

[0021] Figure 2 A schematic diagram of motion compensation according to an embodiment of the present invention;

[0022] In the figure: 1. Mechanism support strut; 2. Belly support strut; 3. Rod control motor; 4. Three-degree-of-freedom hinge device; 5. Test measurement and control computer; 6. Airborne angle sensor; 7. Motor communication cable; 8. Sensor communication cable; 9. Wind tunnel test model. DETAILED DESCRIPTION

[0023] The technical solution of the present invention will be clearly and completely described below in conjunction with the embodiments. Obviously, the described embodiments are part of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0024] 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", "clockwise", "counterclockwise" and the like 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 present invention and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as limiting the present invention.

[0025] In addition, the terms "first" and "second" are only used for descriptive purposes and cannot be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Therefore, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features. In the description of the present invention, "multiple" means two or more, unless otherwise clearly and specifically defined. In addition, the terms "installed", "connected" and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal connection of two components. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0026] Example 1

[0027] like Figure 1-Figure 2 As shown,

[0028] A test device for a high-angle-of-attack wind tunnel virtual flight test, comprising a mechanism support strut 1, a belly support strut 2, a strut control motor 3, a three-degree-of-freedom hinge device 4, a test measurement and control computer 5, an airborne angle sensor 6, a motor communication cable 7, a sensor communication cable 8, and a wind tunnel test model 9. Among them:

[0029] The strut control motor 3 is fixed on the mechanism support strut 1 , and the belly support strut 2 is fixed on the strut control motor 3 , and performs attack angle adaptive compensation movement under the drive of the strut control motor 3 .

[0030] like Figure 2 As shown, during the wind tunnel virtual flight test, the angle of attack of the wind tunnel test model 9 increases or decreases under the action of aerodynamic force. At this time, the onboard angle sensor 6 inside the wind tunnel test model 9 will send the current pitch angle information of the model to the test measurement and control computer 5 through the sensor communication cable 8. After receiving the information, the test measurement and control computer 5 will calculate the motor control amount based on the pitch angle information using a certain control algorithm, and then send the motor control amount to the support rod control motor 3 through the motor communication cable 7.

[0031] Under the drive of the strut control motor 3, the belly support strut 2 starts to follow the change of the model's angle of attack. When the model's angle of attack increases, the belly support strut 2 also rotates clockwise with the model. When the model's angle of attack decreases, the belly support strut 2 rotates counterclockwise with the model. The belly support strut 2 and the wind tunnel test model 9 are always kept in a nearly vertical state as much as possible to avoid interference and collision between the belly support strut 2 and the fuselage.

[0032] The present invention ingeniously transmits the normal force of the test model to the radial direction of the strut control motor 3, and the output torque of the strut control motor 3 is mainly used to overcome the axial load of the test model. Considering that the normal load of the wind tunnel model is much greater than the axial load, the torque demand of the strut control motor 3 is reduced, thereby reducing the motor size and reducing the resulting aerodynamic interference. In addition, by setting a reasonable motor control algorithm, the soft adaptive follow-up of the abdominal support strut 2 is achieved, ensuring smooth movement of the model during the test.

[0033] The invention has a simple implementation approach, expands the angle of attack range of a traditional wind tunnel virtual flight test, and can be used for dynamic virtual flight tests with medium and large angles of attack as test objects.

[0034] The test device of the present invention for a virtual flight test in a high-angle-of-attack wind tunnel, when in use:

[0035] First, the device layout design includes:

[0036] The bottom of the mechanism support strut 1 is fixed on the wind tunnel floor, and the other end is used to fix the strut control motor 3. The output end of the strut control motor 3 is connected to the belly support strut 2, and the top of the belly support strut 2 is connected to the three-degree-of-freedom hinge mechanism inside the wind tunnel test model 9, so that the model can rotate freely around three degrees of freedom under the support of the belly support strut 2. An airborne angle sensor 6 for measuring the attitude angle is arranged inside the wind tunnel test model 9;

[0037] Secondly, the working principle of the device control system is:

[0038] During the test, the attitude angle sensor located inside the wind tunnel test model 9 measures the pitch angle of the model in real time, and the pitch angle is transmitted to the test measurement and control computer 5 through the sensor communication cable 8. The test measurement and control computer 5 generates a motor control signal according to the corresponding motor control algorithm and sends it to the support rod control motor 3 through the motor communication cable 7, thereby realizing the function of the motor driving the abdominal support rod 2 to follow the model attitude angle movement.

[0039] The control algorithm of the motor here is: adding a first-order inertia link between the motor control target angle and the attitude sensor measurement angle. This method can increase the stability of motor control when the angle sensor has large noise or when the attitude angle oscillates rapidly.

[0040] Specifically, the adaptive abdominal support strut 2 needs to move with the model so that the axis of the model body and the abdominal support strut 2 are always in an approximately vertical state, avoiding the situation where the abdominal support strut 2 and the model collide. However, during the actual control process, when the pitch angle of the model changes rapidly, the motor will also rotate rapidly. Especially for the process of rapid reciprocating motion of the pitch angle, the model will experience violent oscillations under the drive of the motor. Therefore, the present invention adds a first-order inertia link between the model pitch angle and the motor control angle to mitigate the motor movement, thereby making the model's movement more stable. Assume that the pitch angle change of the model collected by the onboard angle sensor 6 located inside the model is Δθ model To ensure that the abdominal support rod 2 is always perpendicular to the axis of the model body, the rotation control target angle of the support rod control motor 3 should also be Δθ model After adding the first-order inertia link, the actual control target angle of the support rod control motor 3 becomes Δθ model ×G(s), where G(s) is the first-order system transfer function In the formula, the time constant T needs to be adjusted according to the test conditions. The smaller it is, the faster the abdominal support rod follows, and vice versa, the larger it is, the slower it follows.

[0041] The model of the present invention adopts a design of belly support and direct drive by a miniaturized motor, so that the larger normal aerodynamic load of the model is borne by the motor radially, and the output torque of the motor is mainly used to overcome the axial aerodynamic force of the model. Considering that the normal load of a general aircraft is much larger than the axial load, this greatly reduces the load of the strut control motor, and a small-sized motor can meet the requirements, thereby reducing the aerodynamic interference caused by the motor. This is especially true for situations where the pitch angle is large and the control motor is located upstream of the model.

[0042] The present invention can adaptively adjust the belly support according to the current angle of attack of the test model during the virtual flight test in the wind tunnel, thereby realizing a dynamic mechanism design scheme with the ability of large angle of attack dynamic test. The present invention can greatly reduce the driving torque of the strut control motor and reduce the size of the driving motor.

[0043] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A test device for high angle of attack wind tunnel virtual flight test, characterized in that: It includes a mechanism support strut, a belly support strut, a strut control motor, a test measurement and control computer, an airborne angle sensor and a wind tunnel test model, wherein the strut control motor is fixed on the mechanism support strut, the belly support strut is fixed on the strut control motor, and the belly support strut performs attack angle adaptive compensation movement under the drive of the strut control motor; the wind tunnel test model is fixed on the belly support strut, an airborne angle sensor is arranged inside the wind tunnel test model, and the strut control motor and the airborne angle sensor are connected to the test measurement and control computer.

2. The test device for high angle of attack wind tunnel virtual flight test according to claim 1, characterized in that: A three-degree-of-freedom hinge device is fixed on the wind tunnel test model, and the three-degree-of-freedom hinge device is connected to the abdominal support strut.

3. The test device for high angle of attack wind tunnel virtual flight test according to claim 1, characterized in that: The airborne angle sensor is connected to the test measurement and control computer via a sensor communication cable.

4. The test device for high angle of attack wind tunnel virtual flight test according to claim 1, characterized in that: The support rod control motor is connected to the test measurement and control computer through a motor communication cable.

5. The test device for high angle of attack wind tunnel virtual flight test according to claim 1, characterized in that: The airborne angle sensor is an attitude angle sensor.

6. The test device for high angle of attack wind tunnel virtual flight test according to claim 1, characterized in that: Driven by the strut control motor, the belly support strut follows the change of the attack angle of the wind tunnel test model.

7. The test device for high angle of attack wind tunnel virtual flight test according to claim 6, characterized in that: When the angle of attack of the wind tunnel test model increases, the belly support strut also rotates clockwise along with the wind tunnel test model. When the angle of attack of the wind tunnel test model decreases, the belly support strut rotates counterclockwise along with the wind tunnel test model, so that the belly support strut is always perpendicular to the axis of the wind tunnel test model to avoid interference and collision between the belly support strut and the fuselage of the wind tunnel test model.

8. The test method of the test device for high angle of attack wind tunnel virtual flight test according to claim 1, characterized in that: The steps include: S1. The bottom of the mechanism support rod is fixed on the wind tunnel floor, and the other end of the mechanism support rod is used to fix the rod control motor. The output end of the rod control motor is connected to the belly support rod, and the top of the belly support rod is connected to the three-degree-of-freedom hinge mechanism inside the wind tunnel test model; the wind tunnel test model is supported by the belly support rod to rotate freely around three degrees of freedom, and an airborne angle sensor for measuring the attitude angle is arranged inside the wind tunnel test model; S2. During the test, the onboard angle sensor located inside the wind tunnel test model measures the pitch angle of the model in real time, and the pitch angle is transmitted to the test measurement and control computer. The test measurement and control computer generates a motor control signal according to the corresponding motor control algorithm and sends it to the strut control motor, thereby realizing that the strut control motor drives the abdominal support strut to follow the model's attitude angle movement.

9. The test method according to claim 8, characterized in that A first-order inertia link is added between the target angle controlled by the support rod control motor and the angle measured by the attitude angle sensor onboard the aircraft, which increases the stability of the motor control when the angle sensor has large noise or the attitude angle oscillates rapidly.

10. The test method according to claim 9, characterized in that: The model pitch angle change collected by the airborne angle sensor is Δθ model To ensure that the belly support rod is always perpendicular to the axis of the model body, the rotation control target angle of the support rod control motor should also be Δθ model After adding the first-order inertia link, the actual control target angle of the strut control motor becomes Δθ model × G(s), where G(s) is the first-order system transfer function In the formula, the time constant T needs to be adjusted according to the test conditions. The smaller it is, the faster the abdominal support rod follows, and vice versa, the larger it is, the slower it follows.

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