Automatic protection device and method for preventing attitude divergence of wind tunnel virtual flight model

Abstract

The invention discloses an automatic protection device and method for preventing attitude divergence of a wind tunnel virtual flight model. The automatic protection device comprises an MEMS measurement module, a gas source, a pressure regulating valve, an electromagnetic valve, a gas circuit, a reciprocating cylinder, a push head and an upper computer. Motion state variables of the model are measured through the MEMS measurement module, and the state variables are fed back to the upper computer. The upper computer judges whether the model state variable reaches a set value or not and controls the electromagnetic valve to open and close the gas circuit to achieve pushing-in / withdrawing of the air cylinder pushing head, and the purposes of releasing / limiting model movement and rapidly and automatically protecting the model are achieved. According to the actual test condition, the purposes of adjusting the automatic protection speed and changing the automatic protection condition can be achieved respectively by adjusting the air source pressure and the state variable set value.

Description

Technical Field

[0001] The invention relates to an automatic protection device and method for preventing a wind tunnel virtual flying model from diverging in attitude, and belongs to the field of experimental aerodynamics. Background Art

[0002] Virtual flight wind tunnel test technology is an advanced wind tunnel test and flight performance evaluation technology. During the test, the scaled model of the aircraft research object can perform multi-degree-of-freedom motion within a certain range in the wind tunnel. The specific degrees of freedom and range of motion are related to the content of the test research. During the test, the test model is subjected to corresponding aerodynamic and dynamic effects in the flight environment simulated by the wind tunnel and the current flight state, and these two effects are also interacting and coupled. Under the joint coupling of aerodynamics and dynamics, the attitude changes of the test model within the allowable range can be measured and collected by the measurement system and used as feedback input in flight control. Therefore, virtual flight wind tunnel test technology can provide the comprehensive quality of the flight dynamics and control system of the aircraft research object.

[0003] In most wind tunnel tests, the model and the strut are rigidly connected by a balance. In virtual flight wind tunnel tests, the model and the strut are connected by a multi-degree-of-freedom motion support mechanism, which can move freely within a certain degree of freedom and a certain range. At the same time, some extreme flight conditions and dangerous flight situations are often simulated in wind tunnel virtual flight tests. Therefore, during the test, it is very easy for the model to vibrate, shake, tip over, and other dangerous situations, which require rapid protection or auxiliary support.

[0004] Traditional wind tunnel virtual flight tests do not have protective devices, and when dangerous situations occur, measures such as emergency shutdown of the wind tunnel are generally used to deal with them. This not only affects the test efficiency and wastes the number of tests, but also takes a long time to respond to emergency protection, which can easily increase the degree of danger. Summary of the invention

[0005] The technical problem solved by the present application is to overcome the deficiencies of the prior art and provide an automatic protection device for preventing the attitude divergence of a wind tunnel virtual flight model, thereby making up for the deficiencies in the protection capability of the existing wind tunnel virtual flight test model.

[0006] The technical solutions provided by this application are as follows:

[0007] An automatic protection device for preventing a virtual flying model in a wind tunnel from diverging in attitude comprises a MEMS measurement module, an air source, an air path, a branch, b branch, a reciprocating cylinder and a push head, wherein the MEMS measurement module is connected to the model, the inner cavity of the model is connected to a support rod through a multi-degree-of-freedom support mechanism, and the other end of the support rod is connected to a bracket of a wind tunnel body; the reciprocating cylinder is installed on the support rod, the piston rod end of the reciprocating cylinder is connected to the push head, the reciprocating cylinder has two air cavities, and the two air cavities of the reciprocating cylinder are respectively connected to branch a and branch b. The a branch and b branch, the other ends of the a branch and the b branch are connected to the air circuit, and the other end of the air circuit is connected to the air source; by controlling the connection between the a branch or the b branch and the air circuit, the reciprocating cylinder is controlled to drive the push head to retract or push out. When the push head retracts, the model is in a free motion state. When the push head pushes out of the model cavity, the movement of the model is restricted; the MEMS measurement module is connected to the model, and the measurement module is used to measure the model motion state variables to obtain measurement results, and the a branch or the b branch and the air circuit are controlled according to the measurement results.

[0008] The a branch, b branch and the gas circuit are connected via a solenoid valve, and the solenoid valve is used to control the connection between the a branch or the b branch and the gas circuit.

[0009] It also includes a host computer, which is connected to the solenoid valve; the MEMS measurement module feeds back the measurement results of the model motion state variables to the host computer, and the host computer controls the solenoid valve according to the received state variables to control the connection between branch a or branch b and the gas path.

[0010] The gas circuit is provided with a pressure regulating valve to adjust the air pressure of the gas source.

[0011] The multi-degree-of-freedom support mechanism comprises a fixed end, a multi-degree-of-freedom support assembly and a free end, wherein the fixed end and the free end are both connected to the multi-degree-of-freedom support assembly, the other end of the fixed end is connected to the support rod, and the other end of the free end is connected to the model, and the free end and the model and the support rod are operated with multiple degrees of freedom through the multi-degree-of-freedom support assembly; when the push head is pushed out of the inner cavity of the model, the push head is in hard contact with the inner wall of the model or the free end of the multi-degree-of-freedom support mechanism.

[0012] A protection method for an automatic protection device for preventing a wind tunnel virtual flight model from diverging in attitude, comprising:

[0013] In the initial state, the push head is in a retracted state;

[0014] The MEMS measurement module measures the state variables of the model in real time and feeds the state variables back to the host computer until the host computer determines that the state variables of the model reach the set value. The host computer then controls the solenoid valve to connect branch a or branch b to the gas path.

[0015] The host computer sets the set values ​​of the state variables of the model as automatic protection conditions.

[0016] In summary, this application at least includes the following beneficial technical effects:

[0017] (1) The present invention can automatically and quickly limit the movement of the model to protect or provide auxiliary support when dangerous situations such as model vibration, shaking, and tipping occur during a wind tunnel virtual flight test.

[0018] (2) The present invention can adjust the gas source pressure and the state variable setting value according to the actual test situation to achieve the purpose of adjusting the automatic protection speed and changing the automatic protection conditions. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 It is a structural schematic diagram of the present invention.

[0020] Explanation of the accompanying figures: 1. MEMS measurement module; 2. Gas source; 3. Pressure regulating valve; 4. Solenoid valve; 5. Gas circuit; 6. Cylinder; 7. Push head; 8. Host computer; 9. Multi-degree-of-freedom support mechanism; 10. Support rod; 11. Model. DETAILED DESCRIPTION

[0021] In order to make the objectives, technical solutions and advantages of the present invention more clear, the embodiments disclosed in the present invention will be further described in detail below with reference to the accompanying drawings.

[0022] The embodiment of the present application discloses an automatic protection device for preventing the attitude divergence of a wind tunnel virtual flight model, comprising: a MEMS measurement module 1, an air source 2, a pressure regulating valve 3, a solenoid valve 4, an air circuit 5, a reciprocating cylinder 6, a push head 7 and a host computer 8. The motion state variables of the model 11 are measured by the MEMS measurement module 1, and the state variables are fed back to the host computer 8. The host computer determines whether the model state variables have reached the set value, and controls the solenoid valve to open and close the air circuit to realize the pushing / retracting of the cylinder push head, thereby achieving the purpose of releasing / limiting the model movement and quickly and automatically protecting the model.

[0023] The specific implementation is as follows:

[0024] like Figure 1 As shown, the structure of the present invention includes: a MEMS measurement module 1, an air source 2, a pressure regulating valve 3, a solenoid valve 4, an air circuit 5, a reciprocating cylinder 6, a push head 7 and a host computer 8.

[0025] One end of the support rod is fixedly connected to the angle of attack motion mechanism in the wind tunnel body, and the other end is connected to the inner cavity of the model 11 through the multi-degree-of-freedom support mechanism 9. The reciprocating cylinder 6 is installed on the support rod 10. The reciprocating cylinder 6 has two air chambers. The two air chambers of the reciprocating cylinder 6 are respectively connected to the a branch and the b branch. The other ends of the a branch and the b branch are connected to the air circuit 5 through the electromagnetic valve 4. The other end of the air circuit 5 is connected to the air source 2. The pressure regulating valve 3 is arranged on the air circuit 5. The pressure regulating valve 3 is used to adjust the air pressure of the air source. The electromagnetic valve 4 is used to control the a branch to be connected to the air circuit 5 and the b branch to be disconnected from the air circuit 5, or to control the a branch to be disconnected from the air circuit 5 and the b branch to be connected to the air circuit 5, so as to realize the push-in / retract movement of the cylinder push head 7 by controlling the air circuit 5 by the electromagnetic valve 4.

[0026] The air medium in the air source 1 passes through the pressure regulating valve 3 and enters the solenoid valve 4 to be divided into two air paths a and b. The solenoid valve 4 can control the opening and closing of the air paths a and b; when the solenoid valve 4 controls the air path a to be opened and the air path b to be closed, the cylinder push head 7 is retracted; when the solenoid valve 4 controls the air path b to be opened and the air path a to be closed, the cylinder push head 7 is pushed into the inner cavity of the model; when the cylinder push head 7 is pushed into the inner cavity of the model, the push head 7 is in hard contact with the inner wall of the model or the free end of the motion support mechanism, which plays a role in limiting the movement of the model.

[0027] Specifically, when the cylinder push head 7 is in hard contact with the inner wall end of the model, since the push head 7 and the inner wall of the model have fixed profiles, when in hard contact, the cylinder push head 7 and the inner wall of the model are in a fixed posture of profile fit, so that there is no relative movement between the model and the support rod, which plays a role in limiting the movement of the model. The motion support mechanism 9 includes a fixed end, a multi-degree-of-freedom support assembly and a free end, the fixed end and the free end are both connected to the multi-degree-of-freedom support assembly, the other end of the fixed end is fixedly connected to the support rod, and the other end of the free end is fixedly connected to the model, and the free end and the model and the support rod perform multi-degree-of-freedom movement through the multi-degree-of-freedom support assembly; as the cylinder push head 7 contacts the free end of the motion support mechanism, the cylinder push head 7 gradually pushes the free end and the model to move, until the cylinder push head 7 contacts the free end of the motion support mechanism, the free end and the model move to the limit position of the degree of freedom between the support rod, so that there is no relative movement between the model and the support rod, which plays a role in limiting the movement of the model.

[0028] The MEMS measurement module 1 measures the model motion state variables and feeds back the state variables to the host computer 9. When the host computer 8 determines that the model state variables reach the set value, it controls the solenoid valve 4 to control the opening and closing states of the gas paths a and b.

[0029] The working principle of the present invention is as follows:

[0030] When the wind tunnel virtual flight test is normal, the model is in a free motion state with a certain degree of freedom. The MEMS measurement module measures the model motion state variables and feeds back the state variables to the host computer. At this time, the solenoid valve keeps air path a in the open state, air path b in the closed state, and the push head in the retracted state.

[0031] When the model is in a dangerous situation such as large vibration, shaking, or tipping, that is, when the model state variable reaches the set value, the upper computer program automatically determines to start protection and sends a command electrical signal to control the solenoid valve to open air path b and close air path a. The push head is quickly pushed into the inner cavity of the model, and hard contacts with the inner wall of the model or the free end of the motion support mechanism, which serves the purpose of limiting the movement of the model, assisting support, and quickly and automatically protecting the model. When the model is in a dangerous situation such as large vibration, shaking, or tipping, the internal structure of the model may be damaged. The use of the protection device of this patent can quickly stop the model from swinging and / or vibrating.

[0032] According to the actual test situation, the air medium pressure of the air source can be adjusted through the pressure regulating valve 3 to achieve the purpose of adjusting the automatic protection speed. The greater the air medium pressure, the faster the cylinder filling speed, the faster the push head moves, and the faster the protection speed.

[0033] According to the actual test situation, the state variable condition value for judging the occurrence of dangerous situations, such as the angular velocity and angular displacement of the model, can be set in the host computer to achieve the purpose of changing the automatic protection triggering conditions. For example, when the angular velocity of the model exceeds 100 degrees per second, or the angular displacement exceeds 60 degrees, the model will be quickly and automatically protected.

[0034] The contents not described in detail in this application specification belong to the common knowledge of those skilled in the art.

[0035] The present application is described in detail above in conjunction with specific implementation methods and exemplary examples, but these descriptions cannot be understood as limiting the present application. Those skilled in the art understand that, without departing from the spirit and scope of the present application, a variety of equivalent replacements, modifications or improvements can be made to the technical solution of the present application and its implementation methods, all of which fall within the scope of the present application. The scope of protection of the present application shall be subject to the attached claims.

Claims

1. An automatic protection device for preventing the attitude divergence of a wind tunnel virtual flight model, characterized in that: The invention comprises a MEMS measurement module (1), an air source (2), an air circuit (5), a branch a, a branch b, a reciprocating cylinder (6) and a push head (7); the inner cavity of the model (11) is connected to a support rod (10) through a multi-degree-of-freedom support mechanism (9); the other end of the support rod (10) is connected to a bracket of a wind tunnel body; the reciprocating cylinder (6) is installed on the support rod (10); the piston rod end of the reciprocating cylinder (6) is connected to the push head (7); the reciprocating cylinder (6) has two air cavities; The two air chambers of the reciprocating cylinder (6) are respectively connected to the a branch and the b branch, the other ends of the a branch and the b branch are connected to the air circuit (5), and the other end of the air circuit (5) is connected to the air source (2); by controlling the a branch or the b branch to be connected to the air circuit (5), the reciprocating cylinder (6) is controlled to drive the push head (7) to retract or push out, when the push head (7) is retracted, the model (11) is in a free motion state, and when the push head (7) is pushed out of the inner cavity of the model, the movement of the model (11) is restricted; The MEMS measurement module (1) is connected to the model (11), and is used to measure the motion state variables of the model (11) to obtain measurement results, and to control the a branch or b branch and the gas path (5) according to the measurement results.

2. The automatic protection device for preventing the attitude divergence of the wind tunnel virtual flight model according to claim 1 is characterized in that: The a branch, the b branch and the gas circuit (5) are connected via an electromagnetic valve (4), and the electromagnetic valve (4) is used to control the connection between the a branch or the b branch and the gas circuit (5).

3. The automatic protection device for preventing the attitude divergence of the wind tunnel virtual flight model according to claim 2 is characterized in that: The system also includes a host computer (8) connected to the electromagnetic valve (4); the MEMS measurement module (1) feeds back the measurement result of the motion state variable of the model (11) to the host computer (8), and the host computer (8) controls the electromagnetic valve (4) according to the received state variable to control the connection between branch a or branch b and the gas path (5).

4. The automatic protection device for preventing the attitude divergence of a wind tunnel virtual flight model according to claim 1 is characterized in that: The gas circuit (5) is provided with a pressure regulating valve (3) to adjust the air pressure of the gas source (2).

5. The automatic protection device for preventing the attitude divergence of a wind tunnel virtual flight model according to claim 1 is characterized in that: The multi-degree-of-freedom support mechanism (9) comprises a fixed end, a multi-degree-of-freedom support assembly and a free end, wherein the fixed end and the free end are both connected to the multi-degree-of-freedom support assembly, the other end of the fixed end is connected to a support rod, and the other end of the free end is connected to a model, and the free end and the model and the support rod are operated in a multi-degree-of-freedom manner through the multi-degree-of-freedom support assembly; when the push head (7) is pushed out of the inner cavity of the model, the push head (7) is in hard contact with the inner wall of the model (11) or the free end of the multi-degree-of-freedom support mechanism (9).

6. A protection method for an automatic protection device for preventing the attitude divergence of a wind tunnel virtual flight model as described in claims 3-5, characterized in that: include: In the initial state, the push head (7) is in a retracted state; The MEMS measurement module (1) measures the state variables of the model (11) in real time and feeds back the state variables to the host computer (8). When the host computer (8) determines that the state variables of the model (11) have reached a set value, the host computer (8) controls the solenoid valve (4) to connect branch a or branch b to the gas path (5).

7. The protection method according to claim 6, characterized in that: The host computer (8) sets the set value of the state variable of the model (11) as an automatic protection condition.

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