阅读说明：本技术 基于压力和流速的大气参数传感系统和需求参数计算方法 (Atmospheric parameter sensing system based on pressure and flow rate and demand parameter calculation method ) 是由 蒋永刚 纳新 董子豪 于 2021-08-12 设计创作，主要内容包括：本发明涉及一种基于压力和流速的大气参数传感系统和需求参数计算方法,所述系统包括：用于获取压力数据和流速数据的传感模块；用于承载所述传感模块且与所述传感模块电连接的柔性基底电路板；控制电路,用于通过所述柔性基底电路板控制所述传感模块获取所述压力数据和所述流速数据；上位机,用于接收并存储所述压力数据和所述流速数据,并根据所述压力数据和所述流速数据得到解算需求参数。本发明通过获取压力和流速,基于此可以高效地、精准地得到需求参数,提高了需求参数的可靠性,并实现了系统的模块化。(The invention relates to an atmospheric parameter sensing system based on pressure and flow rate and a demand parameter calculation method, wherein the system comprises: the sensing module is used for acquiring pressure data and flow rate data; the flexible substrate circuit board is used for bearing the sensing module and is electrically connected with the sensing module; the control circuit is used for controlling the sensing module to acquire the pressure data and the flow rate data through the flexible substrate circuit board; and the upper computer is used for receiving and storing the pressure data and the flow rate data and obtaining a resolving demand parameter according to the pressure data and the flow rate data. According to the invention, the demand parameters can be efficiently and accurately obtained by acquiring the pressure and the flow rate, the reliability of the demand parameters is improved, and the modularization of the system is realized.)

1. An atmospheric parameter sensing system based on pressure and flow rate, comprising:

the sensing module is used for acquiring pressure data and flow rate data;

the sensing module is arranged on the flexible substrate circuit board and is electrically connected with the flexible substrate circuit board;

the control circuit is connected with the flexible substrate circuit board and used for controlling the sensing module to acquire the pressure data and the flow rate data through the flexible substrate circuit board and receiving the pressure data and the flow rate data;

and the upper computer is connected with the control circuit and used for receiving and storing the pressure data and the flow rate data and obtaining a resolving demand parameter according to the pressure data and the flow rate data.

2. A pressure and flow rate based atmospheric parameter sensing system as defined in claim 1, wherein the sensing module comprises:

the N pressure sensing units are arranged on the flexible substrate circuit board, are electrically connected with the flexible substrate circuit board and are used for acquiring the pressure data; n is a positive integer greater than or equal to 3;

and the N flow rate sensing units are arranged on the flexible substrate circuit board, are electrically connected with the flexible substrate circuit board and are used for acquiring the flow rate data.

3. The atmospheric parameter sensing system according to claim 2, wherein the pressure sensing units are equally spaced along a straight line, the flow rate sensing units are equally spaced along a same direction in a step shape, the flow rate sensing units are symmetrically spaced along a center line, and the spacing between the pressure sensing units is the same as the spacing between the flow rate sensing units.

4. A pressure and flow rate based atmospheric parameter sensing system according to claim 2, wherein a flexible gasket having the same thickness is disposed between each flow rate sensing unit and the flexible substrate circuit board, and the sum of the thicknesses of the flexible gasket and the flow rate sensing unit is equal to the thickness of the pressure sensing unit.

5. The atmospheric parameter sensing system based on pressure and flow rate of claim 3, wherein the distance between the pressure sensing unit and the flow rate sensing unit on the same straight line is larger than a preset distance; the preset interval is 1.5 times the width of the pressure sensing unit.

6. A pressure and flow rate based atmospheric parameter sensing system according to claim 4, wherein the flexible base circuit board is coated with a flexible skin, and the thickness of the flexible skin is the same as that of the pressure sensing unit; the upper surfaces of the pressure sensing unit and the flow rate sensing unit are flush with the outer surface of the flexible skin.

7. The pressure and flow rate based atmospheric parameter sensing system of claim 4, wherein the flexible gasket is made of polyimide.

8. A method of calculating demand parameters based on pressure and flow rate, the method being adapted for use in a system according to any one of claims 1 to 7, the method comprising:

obtaining a function coefficient of a theoretical demand parameter based on a training database;

obtaining the theoretical demand parameter based on the pressure data and the flow rate data;

and obtaining a resolving demand parameter based on the function coefficient and the theoretical demand parameter.

9. The method of claim 8, wherein the deriving a function coefficient of the theoretical demand parameter based on the training database comprises:

obtaining a theoretical demand parameter training database based on a training pressure database and a training flow velocity database;

performing difference on a real demand parameter training database and the theoretical demand parameter training database to obtain a difference database;

obtaining a function coefficient of the theoretical demand parameter based on the difference database and the theoretical demand parameter training database;

the training database includes the training pressure database, the training flow rate database, and the real demand parameter training database.

10. The method of claim 8, wherein the calculated demand parameter is any one of an angle of attack or a sideslip angle.

Technical Field

The invention relates to the technical field of flight parameters, in particular to an atmospheric parameter sensing system based on pressure and flow speed and a demand parameter calculation method.

Background

The aircraft needs to perform accurate flight control in the flight process to ensure the flight safety of the aircraft, and the most important thing is to realize accurate flight control is to obtain various flight parameters of the aircraft in real time, such as sideslip angle, attack angle, mach number and the like of the aircraft. After the data parameters are obtained, the pilot can quickly make a judgment and make a decision to ensure the flight safety of the aircraft.

Conventional atmospheric data measurements are based on pitot tube probe-based sensing systems, which typically include an exposed pitot tube, an angle of attack sensor, a sideslip angle sensor, and the like. The measurement mode has good effect under the steady state conditions of low speed and small attack angle, but with the continuous improvement of the requirements of the speed, the maneuverability, the stealth and the like of the aircraft, the probe type sensing system can not meet the design requirements of the aircraft any more. To solve these problems, FADS (embedded air sensing) systems have been developed in the future, which generally measure the pressure distribution by means of an array of pressure sensors arranged at different locations in the nose of the aircraft and solve the air data by means of specific algorithms. The existing FADS system carries out pressure data measurement by relying on pressure measuring holes on the surface of an aircraft, the existence of the pressure measuring holes destroys the pneumatic appearance of the aircraft to a certain extent and reduces the stealth performance, and pressure measuring points are large in number and are dispersed, so that modularization is difficult to realize.

Disclosure of Invention

In view of the above, to solve the above problems, the present invention provides an atmospheric parameter sensing system based on pressure and flow rate and a demand parameter calculation method, in which the atmospheric parameter is calculated based on pressure data and flow rate data, so as to obtain demand data.

In order to achieve the purpose, the invention provides the following scheme:

an atmospheric parameter sensing system based on pressure and flow rate, comprising:

the sensing module is used for acquiring pressure data and flow rate data;

the sensing module is arranged on the flexible substrate circuit board and is electrically connected with the flexible substrate circuit board;

the control circuit is connected with the flexible substrate circuit board and used for controlling the sensing module to acquire the pressure data and the flow rate data through the flexible substrate circuit board and receiving the pressure data and the flow rate data;

and the upper computer is connected with the control circuit and used for receiving and storing the pressure data and the flow rate data and obtaining a resolving demand parameter according to the pressure data and the flow rate data.

Preferably, the sensing module includes:

the N pressure sensing units are arranged on the flexible substrate circuit board, are electrically connected with the flexible substrate circuit board and are used for acquiring the pressure data; n is a positive integer greater than or equal to 3;

and the N flow rate sensing units are arranged on the flexible substrate circuit board, are electrically connected with the flexible substrate circuit board and are used for acquiring the flow rate data.

Preferably, the pressure sensing units are distributed at equal intervals along a straight line, the flow rate sensing units are distributed at equal intervals in a step shape along the same direction, the flow rate sensing units are symmetrically distributed along a center line, and the interval between the pressure sensing units is the same as the interval between the flow rate sensing units.

Preferably, a flexible gasket with the same thickness is arranged between each flow rate sensing unit and the flexible substrate circuit board, and the sum of the thicknesses of the flexible gasket and the flow rate sensing unit is equal to the thickness of the pressure sensing unit.

Preferably, the distance between the pressure sensing unit and the flow rate sensing unit on the same straight line is greater than a preset distance; the preset interval is 1.5 times the width of the pressure sensing unit.

Preferably, a flexible skin is coated on the flexible base circuit board, and the thickness of the flexible skin is the same as that of the pressure sensing unit; the upper surfaces of the pressure sensing unit and the flow rate sensing unit are flush with the outer surface of the flexible skin.

Preferably, the flexible gasket is made of polyimide.

The invention also provides a demand parameter calculation method based on pressure and flow rate, which is suitable for the system and comprises the following steps:

obtaining a function coefficient of a theoretical demand parameter based on a training database;

obtaining the theoretical demand parameter based on the pressure data and the flow rate data;

and obtaining a resolving demand parameter based on the function coefficient and the theoretical demand parameter.

Preferably, the obtaining of the function coefficient of the theoretical demand parameter based on the training database includes:

obtaining a theoretical demand parameter training database based on a training pressure database and a training flow velocity database;

performing difference on a real demand parameter training database and the theoretical demand parameter training database to obtain a difference database;

obtaining a function coefficient of the theoretical demand parameter based on the difference database and the theoretical demand parameter training database;

the training database includes the training pressure database, the training flow rate database, and the real demand parameter training database.

Preferably, the calculation demand parameter is either one of an angle of attack or a sideslip angle.

According to the specific embodiment provided by the invention, the invention discloses the following technical effects:

the invention relates to an atmospheric parameter sensing system based on pressure and flow rate and a demand parameter calculation method, wherein the system comprises: the sensing module is used for acquiring pressure data and flow rate data; the flexible substrate circuit board is used for bearing the sensing module and is electrically connected with the sensing module; the control circuit is used for controlling the sensing module to acquire the pressure data and the flow rate data through the flexible substrate circuit board; and the upper computer is used for receiving and storing the pressure data and the flow rate data and obtaining a resolving demand parameter according to the pressure data and the flow rate data. According to the invention, the demand parameters can be efficiently and accurately obtained by acquiring the pressure and the flow rate, the reliability of the demand parameters is improved, and the modularization of the system is realized.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings needed to be used in the embodiments will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and it is obvious for those skilled in the art to obtain other drawings without inventive exercise.

FIG. 1 is a block diagram of an atmospheric parameter sensing system based on pressure and flow rate in accordance with the present invention;

FIG. 2 is a diagram of the sensor module and flexible substrate circuit board of the present invention;

FIG. 3 is a cross-sectional view taken at the location A-A in FIG. 2;

FIG. 4 is a schematic view of the installation position of the atmospheric parameter sensing system based on pressure and flow rate according to the present invention;

FIG. 5 is a flow chart of a method of calculating demand parameters based on pressure and flow rate in accordance with the present invention;

FIG. 6 is a graph showing the effect of the demand parameter calculation method based on pressure and flow rate according to the present invention.

Description of the symbols: the method comprises the following steps of 1-a sensing module, 2-a flexible substrate circuit board, 3-a control circuit, 4-an upper computer, 5-a flexible gasket, 6-a flexible skin, 7-a wing, 11-a pressure sensing unit and 12-a flow rate sensing unit.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

The invention aims to provide an atmospheric parameter sensing system based on pressure and flow rate and a demand parameter calculation method, which can quickly and accurately obtain demand parameters according to the obtained pressure and flow rate.

In order to make the aforementioned objects, features and advantages of the present invention comprehensible, embodiments accompanied with figures are described in further detail below.

Fig. 1 is a structural diagram of a pressure and flow rate based parameter sensing system according to the present invention, and as shown in fig. 1, the present invention provides a pressure and flow rate based parameter sensing system, including: the device comprises a sensing module 1, a flexible substrate circuit board 2, a control circuit 3 and an upper computer 4.

The sensing module 1 is configured to obtain pressure data and flow rate data, and specifically, as shown in fig. 2, the sensing module 1 includes N pressure sensing units 11 and N flow rate sensing units 12. N is a positive integer greater than or equal to 3, and in this embodiment, N is 5.

Each of the pressure sensing units 11 and each of the flow rate sensing units 12 are fixedly disposed on the flexible substrate circuit board 2 and electrically connected to the flexible substrate circuit board 2, and each of the pressure sensing units 11 is configured to acquire the pressure data; each of the flow rate sensing units 12 is configured to acquire the flow rate data. In this embodiment, each of the pressure sensing units 11 employs an absolute pressure sensor, and each of the flow rate sensors employs a thermal flow rate sensor. Further, in the present embodiment, each of the pressure sensing units 11 and each of the flow rate sensing units 12 are fixedly disposed on the flexible substrate circuit board 2 by soldering.

In order to improve the robustness of data and maintain the consistency of pressure and flow velocity measurement in the same point, as shown in fig. 2, in the present invention, the pressure sensing units 11 are distributed at equal intervals along a straight line, the flow velocity sensing units 12 are distributed at equal intervals in a step shape along the same direction, the flow velocity sensing units 12 are distributed symmetrically along a center line, and the interval between the pressure sensing units 11 is the same as the interval between the flow velocity sensing units 12.

In order to further improve the accuracy of data acquisition, in the present invention, a flexible gasket 5 with the same thickness is disposed between each flow rate sensing unit 12 and the flexible substrate circuit board 2, so that the working surfaces of the flow rate sensing unit 12 and the pressure sensing unit 11 are in the same horizontal plane, that is, the sum of the thicknesses of the flexible gasket 5 and the flow rate sensing unit 12 is equal to the thickness of the pressure sensing unit 11, as shown in fig. 3. In this embodiment, the flexible gasket 5 is made of polyimide. In this embodiment, the sum of the thicknesses of the pressure sensing unit 11 and the flexible substrate circuit board 2 is less than 1mm, so that miniaturization, light weight and modularization are realized, and mounting can be completed by reserving microgrooves at mounting positions.

Preferably, in order to prevent the heat generated by the flow rate sensing unit 12 during operation from interfering with the pressure sensing unit 11, thereby affecting the operating state of the pressure sensing unit 11, in this embodiment, the distance between the pressure sensing unit 11 and the flow rate sensing unit 12 on the same straight line is greater than a preset distance; the preset interval is 1.5 times the width of the pressure sensing unit 11.

As an alternative embodiment, the flexible base circuit board 2 of the present invention is coated with a flexible skin 6, and the thickness of the flexible skin 6 is the same as that of the pressure sensing unit 11; the upper surfaces of the pressure sensing unit 11 and the flow rate sensing unit 12 are flush with the outer surface of the flexible skin 6; that is, the flexible skin 6 covers the remaining area of the surface of the flexible base circuit board 2 except for the working surfaces of the pressure sensing cells 11 and the flow rate sensing cells 12, thereby obtaining a smooth surface without damaging aerodynamic shape. In this embodiment, the flexible skin 6 is integrally cast on the surface of the flexible substrate circuit board 2 by using a designed mold.

The control circuit 3 is connected to the flexible substrate circuit board 2, and the control circuit 3 is configured to obtain the pressure data through each of the pressure sensing units 11 of the flexible substrate circuit board 2, control each of the flow rate sensing units 12 to obtain the flow rate data, and receive the pressure data and the flow rate data at the same time. The control circuit supplies power to each of the pressure sensing units 11 and each of the flow rate sensing units 12.

The upper computer 4 is connected with the control circuit 3, and the upper computer 4 is used for receiving and storing the pressure data and the flow rate data and obtaining resolving demand parameters according to the pressure data and the flow rate data. In this embodiment, the upper computer 4 is any one of a notebook computer, a microprocessor, a single chip microcomputer and an avionics system. In this embodiment, the upper computer 4 has a display, and performs data output on the calculation demand parameter, or performs visual output on the pressure data and the flow rate data.

The installation position of the atmospheric parameter sensing system based on pressure and flow rate is described by taking an aircraft as an example, as shown in fig. 4, the airfoil of the aircraft is NACA, wherein the sensing module 1 and the flexible substrate circuit board 2 are integrally arranged at the front end of the wing 7, so that data can be accurately acquired, holes are punched at the wing cavity of the wing 7 to place the control circuit 3, and therefore, the surface of the wing 7 is not provided with holes or any lead wires, and the aerodynamic shape of the whole wing 7 cannot be damaged; the upper computer 4 is positioned in the aircraft, can be a central control unit of the aircraft, and can also be an independent computer and the like.

Fig. 5 is a flow chart of a method for calculating demand parameters based on pressure and flow rate according to the present invention, and as shown in fig. 5, the present invention provides a method for calculating demand parameters based on pressure and flow rate, which is suitable for the above system, and the method includes:

step S1, obtaining a function coefficient of the theoretical demand parameter based on the training database; as an alternative embodiment, step S1 of the present invention includes:

and step S11, obtaining a theoretical demand parameter database based on the training pressure database and the training flow velocity database.

And step S12, performing difference on the real demand parameter database and the theoretical demand parameter database to obtain a difference database.

And step S13, obtaining a function coefficient of the theoretical demand parameter based on the difference database and the theoretical demand parameter database. The training database includes the training pressure database, the training flow rate database, and the real demand database.

And step S2, obtaining the theoretical demand parameter based on the pressure data and the flow rate data.

And step S3, obtaining a calculation demand parameter based on the function coefficient and the theoretical demand parameter. In this embodiment, the calculation demand parameter is any one of an attack angle and a sideslip angle.

The above method is explained in detail by taking an attack angle as an example:

the attack angle is solved based on a three-point method, and any three points i, j and k are selected based on a certain group of data in a training database; i belongs to M; j is an element of M; k belongs to M, and M is the number of the pressure sensing units/flow rate sensing units; based on the formula P ═ q_c(cos²θ+εsin²θ)+P_∞Obtaining the pressure P at three points i, j, k_i，P_j，P_k。

Wherein P is pressure, q_cTheta is the incident angle, epsilon is the profiling coefficient, P_∞Is the incoming hydrostatic pressure.

Further obtain

Defining: gamma-shaped_ij＝P_i-P_j，Γ_jk＝P_j-P_k，Γ_ki＝P_k-P_i(ii) a Substituting the formula to obtain gamma_ijcos²θ_k+Γ_jkcos²θ_i+Γ_kicos²θ_j＝0。

And because of theta and alpha₀And beta₀There is a functional relationship between the following components,

in the formula: alpha is alpha₀To a theoretical angle of attack, beta₀To the theoretical sideslip angle, phi_iIs the circumferential angle of the ith point, λ_iThe cone angle at point i.

Make beta₀At 0 deg. then has cos theta_i＝cosα₀cosλ-sinα₀sinλ＝acosα₀+bsinα₀(ii) a Further obtaining A (tan)²α₀-1)+2Btanα₀＝0。

Wherein the content of the first and second substances,

solve the equation to

Based on the flow velocity equation V ═ η V_∞sin theta, selecting any two points i, j to solve the equation and dividing by the square

In the formula: v is the flow velocity, eta is the flow velocity coefficient, V_∞Is the incoming flow velocity.

Defining:thereby obtaining pi_ij＝Π_icos²θ_j-Π_jcos²θ_iSimilarly, get pi_jkII_ki。

Arrange to obtain pi_ijcos²θ_jk+Π_jkcos²θ_i+Π_kicos²θ_jWhen the residue is equal to 0, C (tan) is further obtained²α₀-1)+2Dtanα₀＝0。

Wherein the content of the first and second substances,the solution can be obtained

For formula Γ_ijcos²θ_k+Γ_jkcos²θ_i+Γ_kicos²θ_j0 and formula #_ijcos²θ_jk+Π_jkcos²θ_i+Π_kicos²θ_jAdding 0 can yield cos²θ_jk+Π_jkcos²θ_i+Π_ijcos²θ_jk+Π_jkcos²θ_i+Π_kicos²θ_j0, the formula cos θ_i＝cosα₀cosλ-sinα₀sinλ＝acosα₀+bsinα₀Substituting into the above formula to obtain E (tan)²α₀-1)+2Ftanα₀＝0。

Wherein the content of the first and second substances,solving the equation to obtainBased on the method, a theoretical attack angle can be obtained for each group of data, so that a theoretical attack angle database is obtained, the real attack angle database and the theoretical attack angle database are correspondingly subjected to difference making, a difference database can be obtained, a scatter diagram is obtained based on the difference database and the theoretical attack angle database, and further function fitting is carried out to obtain a function relation X (alpha) of the theoretical attack angle₀)。

Thus, a calculation formula for the angle of attack is obtained: alpha is alpha_Calculate＝X(α₀)+α₀. In the formula: alpha is alpha_CalculateTo solve for the angle of attack.

And substituting the pressure data and the flow speed data obtained based on real-time measurement into a calculation formula for calculating the attack angle to obtain the real-time calculated attack angle.

Fig. 5 shows the result of testing the real-time output attack angle of the NACA airfoil model equipped with the system of the present invention at the wind speed of 15m/s, and the average value of the specific values is shown in table 1, which shows that the system has a fast response rate to the change of the attack angle, the resolution precision of the attack angle is less than 0.4 °, and the system has good repeatability.

TABLE 1 Angle of attack comparison table

The embodiments in the present description are described in a progressive manner, each embodiment focuses on differences from other embodiments, and the same and similar parts among the embodiments are referred to each other.

The principles and embodiments of the present invention have been described herein using specific examples, which are presented solely to aid in the understanding of the systems, methods, and core concepts of the invention; meanwhile, for a person skilled in the art, according to the idea of the present invention, the specific embodiments and the application range may be changed. In view of the above, the present disclosure should not be construed as limiting the invention.