A parameterized measurement point space position generation method for test model design

Abstract

The application discloses a parameterized measuring point space position generation method for test model design, which comprises the following steps: firstly, generating a straight line segment in a three-dimensional space; based on the straight line segment, obtaining a parameterized straight line segment group through linear array or circular array; solving the parameterized straight line segment group and test model curved surface expression to obtain all intersection point coordinates; taking all intersection point coordinates as measuring point space positions; after the test model is processed, processing sensor holes at all measuring point space positions, installing sensors in the sensor holes, and acquiring surface physical quantities of all measuring points of the model by using the sensors. The measuring point generation method has the advantages of fast iteration, easy standardization and parameterization, and can ensure that the relative positions of the measuring points on the surfaces of models with different scales are consistent.

Description

Technical Field

[0001] This invention relates to the field of aircraft test design, and in particular to a method for generating parametric measurement point spatial coordinates for test model design. Background Technology

[0002] In point measurement tests of physical quantities on the surface of aircraft test models, such as pressure, heat flow, and friction, various contact sensors are often used to measure the required physical quantities. The design of measurement points in actual test models often has the following characteristics:

[0003] 1) The aircraft's shape is a complex curved surface;

[0004] 2) Measurement points for models with different scales must be in the same relative spatial position;

[0005] 3) The location of the measuring points needs to go through multiple rounds of design and iteration.

[0006] Therefore, there is a need for a method that makes the design process of measurement points for experimental models more convenient and efficient, and ensures that measurement points of models with different scales are in the same relative spatial position. Summary of the Invention

[0007] The technical problem solved by this invention is to overcome the shortcomings of the prior art and provide a parameterized measurement point spatial coordinate generation method for experimental model design. This method can be more efficient by adjusting parameters and ensure that the measurement points of models with different scales are in the same relative spatial position.

[0008] The technical solution of this invention is: a method for generating the spatial location of parameterized measurement points for experimental model design, comprising:

[0009] Generate a straight line segment in three-dimensional space;

[0010] Based on this straight line, a parameterized group of straight line segments can be obtained by using a linear array or a circular array.

[0011] Solve the parametric line segment group and the surface expression of the experimental model simultaneously to obtain the coordinates of all intersection points;

[0012] Using the coordinates of all intersection points as the spatial locations of the measurement points, the sensors of the test model are installed at the spatial locations of the measurement points. The sensors are then used to measure the physical quantities of the model surface.

[0013] Furthermore, when the scale of the experimental model changes, the spatial position of the generated measurement points is changed by adjusting the parameter values ​​of the linear array or circular array proportionally.

[0014] Furthermore, the linear array includes a single-direction linear array in Cartesian coordinates and a two-direction linear array in Cartesian coordinates.

[0015] Furthermore, the steps for obtaining the spatial position of the measuring point using a two-direction linear array of Cartesian coordinates include:

[0016] Generate a straight line segment, x = x1, y = y1, z ∈ (Z). min Z max );

[0017] By performing a linear array along the x and y axes according to certain parameters, the following group of lines controlled by the x and y coordinates is obtained:

[0018] x = x1, y = y1, z ∈ (Z) min Z max )

[0019] x = x2, y = y1, z ∈ (Z) min Z max )

[0020] ...

[0021] x = x N y = y1, z ∈ (Z min Z max )

[0022] x = x1, y = y2, z ∈ (Z) min Z max )

[0023] x = x², y = y², z ∈ (Z) min Z max )

[0024] ...

[0025] x = x N y = y2, z ∈ (Z min Z max )

[0026] ...

[0027] x = x1, y = y N , z∈(Z min Z max )

[0028] x = x², y = y N , z∈(Z min Z max )

[0029] ...

[0030] x = x Ny = y N , z∈(Z min Z max )

[0031] Solving the system of equations for the straight line group and the experimental model surface z = f(x,y) simultaneously yields the coordinates of the intersection point:

[0032]

[0033]

[0034] The spatial positions of the measuring points are obtained as (x1, y1, z1), (x2, y2, z2), (x3, y3, z3)...(x N ,y N ,z N ), where x1……x N ,y1……y N ,z min ,z max For parameters.

[0035] Furthermore, the circular array includes a single-direction array in cylindrical coordinates and a two-direction array in cylindrical coordinates.

[0036] Furthermore, the steps for obtaining the spatial position of the measuring point using a two-direction array of cylindrical coordinates include:

[0037] Generate one line segment θ = θ1, Z = Z1, ρ ∈ (ρ min ,ρ max );

[0038] The following is a group of linear segments in an array controlled by parameters such as circumferential angle and normal:

[0039] θ = θ1, Z = Z1, ρ ∈ (ρ min ,ρ max );

[0040] θ = θ2, Z = Z1, ρ ∈ (ρ min ,ρ max );

[0041] ...

[0042] θ=θ N Z = Z1, ρ ∈ (ρ min ,ρ max );

[0043] θ = θ1, Z = Z2, ρ ∈ (ρ min ,ρ max );

[0044] θ = θ², Z = Z², ρ ∈ (ρ min ,ρmax );

[0045] ...

[0046] θ=θ N Z = Z2, ρ ∈ (ρ min ,ρ max );

[0047] ...

[0048] θ = θ1, Z = Z N ,ρ∈(ρ min ,ρ max );

[0049] θ = θ², Z = Z N ,ρ∈(ρ min ,ρ max );

[0050] ...

[0051] θ=θ N Z = Z N ,ρ∈(ρ min ,ρ max );

[0052] Solving the equations simultaneously for the group of line segments and the surface z = f(θ, ρ) of the experimental model yields the coordinates of the intersection point:

[0053]

[0054] The spatial positions of the measuring points are obtained as (θ1,z1,ρ1), (θ2,z2,ρ2), (θ3,z3,ρ3)……(θ N ,z N ,ρ N ), where θ1……θ N ,z 1…… z N ,ρ min ,ρ max For parameters.

[0055] Furthermore, the test model is an aircraft model, and the physical quantities include pressure, heat flow, and friction. In the pressure, heat flow, and friction point measurement test, the pressure, heat flow, and friction on the surface of the aircraft are obtained to provide wind tunnel test data for the aerodynamic shape design of the aircraft and optimize the aerodynamic shape design of the aircraft.

[0056] The advantages of this invention compared to the prior art are:

[0057] (1) By generating a group of straight lines in an array and then solving for the intersection of the group of straight lines and the surface, dozens or even hundreds of measurement points can be generated quickly and easily.

[0058] (2) When arraying, the line group is determined by parameterization. By adjusting the control parameters (which can be the x, y, and z coordinates in the Cartesian coordinate system, or the θ, z, and ρ coordinates in the cylindrical coordinate system, the position of the measuring point can be redesigned and iterated quickly, thereby improving design efficiency and reducing iteration time and cost. Attached Figure Description

[0059] Figure 1 This is a schematic diagram of the measurement point generation method according to an embodiment of the present invention. Detailed Implementation

[0060] To better understand the technical solution of the present invention, the embodiments of the present invention will be described in detail below with reference to the accompanying drawings.

[0061] 1. The process of generating the position of the measuring point linearly in one direction using the Cartesian coordinate system:

[0062] (1) Generate a straight line or line segment in three-dimensional space, such as line segment x = x1, y = y1, z ∈ (z min ,z max );

[0063] (2) A parameterized group of line segments is obtained by using a unidirectional linear array method. For example, a linear array along the x-axis will result in a group of line segments controlled by the x-coordinate as a parameter, as follows:

[0064] Line segment 1: x = x1, y = y1, z ∈ (z min ,z max )

[0065] Line segment 2: x = x², y = y₁, z ∈ (z min ,z max )

[0066] Line segment 3: x = x³, y = y¹, z ∈ (z min ,z max )

[0067] ...

[0068] Line segment N: x = x N y = y1, z ∈ (z min ,z max )

[0069] (3) Solve the equations of the line segment group and the experimental model surface to obtain the coordinates of the intersection point:

[0070]

[0071] The coordinates of the measuring points are obtained as (x1, y1, z1), (x2, y1, z2), (x3, y1, z3)...(x N,y1,z N )

[0072] Where x1……x N ,y1,z min ,z max For parameters.

[0073] 2. The process of linearly generating the position of the measuring point in two directions using a Cartesian coordinate system:

[0074] (1) Generate a straight line or line segment in three-dimensional space, such as line segment x = x1, y = y1, z ∈ (z min ,z max );

[0075] (2) A parameterized group of lines is obtained by using a two-direction linear array method. For example, a linear array along the x and y axes will result in a group of line segments controlled by the x and y coordinates as parameters, as follows:

[0076] x = x1, y = y1, z ∈ (z min ,z max )

[0077] x = x2, y = y1, z ∈ (z min ,z max )

[0078] ...

[0079] x = x N y = y1, z ∈ (z min ,z max )

[0080] x = x1, y = y2, z ∈ (z min ,z max )

[0081] x = x², y = y², z ∈ (z min ,z max )

[0082] ...

[0083] x = x N y = y2, z ∈ (z min ,z max )

[0084] ...

[0085] x = x1, y = y N , z∈(z min ,z max )

[0086] x = x², y = y N , z∈(z min,z max )

[0087] ...

[0088] x = x N y = y N , z∈(z min ,z max )

[0089] (3) Solve the equations of the line segment group and the experimental model surface to obtain the coordinates of the intersection point:

[0090]

[0091]

[0092] The coordinates of the measuring points are obtained as (x1, y1, z1), (x2, y2, z2), (x3, y3, z3)...(x N ,y N ,z N )

[0093] Where x1……x N ,y1……y N ,z min ,z max For parameters.

[0094] 3. Process of generating the position of the measuring point in a single direction using a cylindrical coordinate system:

[0095] (1) Generate a straight line or line segment in three-dimensional space, such as line segment θ=θ1, z=z1, ρ∈(ρ min ,ρ max );

[0096] (2) By obtaining a parameterized group of lines through the single-circle array method, the group of line segments with the circumferential angle controlled by the parameter is as follows:

[0097] θ = θ1, z = z1, ρ ∈ (ρ min ,ρ max );

[0098] θ = θ2, z = z1, ρ ∈ (ρ min ,ρ max );

[0099] ...

[0100] θ=θ N , z = z1, ρ ∈ (ρ min ,ρ max );

[0101] (3) Solve the equations of the line segment group and the experimental model surface to obtain the coordinates of the intersection point:

[0102]

[0103] The coordinates of the measuring points are obtained as (θ1, z1, ρ1), (θ2, z1, ρ2), (θ3, z1, ρ3)...(θ N ,z1,ρ N )

[0104] Where, θ1……θ N ,z1,ρ min ,ρ max For parameters

[0105] 4. The process of generating the position of the measuring point in two directions using a cylindrical coordinate system:

[0106] (1) Generate a straight line or line segment in three-dimensional space, such as line segment θ=θ1, z=z1, ρ∈(ρ min ,ρ max );

[0107] (2) By using the two-direction array method to obtain a parameterized group of lines, the group of line segments with the inscribed angle and normal direction controlled by parameters is as follows:

[0108] θ = θ1, z = z1, ρ ∈ (ρ min ,ρ max );

[0109] θ = θ2, z = z1, ρ ∈ (ρ min ,ρ max );

[0110] ...

[0111] θ=θ N , z = z1, ρ ∈ (ρ min ,ρ max );

[0112] θ = θ1, z = z2, ρ ∈ (ρ min ,ρ max );

[0113] θ = θ², z = z², ρ ∈ (ρ min ,ρ max );

[0114] ...

[0115] θ=θ N , z = z2, ρ ∈ (ρ min ,ρ max );

[0116] ...

[0117] θ = θ1, z = z N ,ρ∈(ρmin ,ρ max );

[0118] θ = θ², z = z N ,ρ∈(ρ min ,ρ max );

[0119] ...

[0120] θ=θ N , z = z N ,ρ∈(ρ min ,ρ max );

[0121] (3) Solve the equations of the line segment group and the experimental model surface to obtain the coordinates of the intersection point:

[0122]

[0123]

[0124] Obtain the measuring point coordinates (θ1,z1,ρ1), (θ2,z2,ρ2), (θ3,z3,ρ3)...(θ N ,z N ,ρ N )

[0125] Where, θ1……θ N ,z 1…… z N ,ρ min ,ρ max For parameters.

[0126] 5. Process of generating measurement point locations after adjusting the model scale:

[0127] After the model scale is adjusted, the coordinates of the measurement points can be generated by adjusting the model scale i.

[0128] Under the Cartesian coordinate system conditions, it is only necessary to let

[0129] x' = x / i;

[0130] y'=y / i

[0131] z'=z / i

[0132] In cylindrical coordinates:

[0133] θ'=θ / i

[0134] z'=z / i

[0135] ρ'=ρ / i

[0136] In addition, the generated measurement points can be accessed in different coordinate systems via (z...min ,z max ) or (ρ min ,ρ max The selection is based on the range of variation within a given interval.

[0137] It is understood that this invention has been described through embodiments, and those skilled in the art will recognize that various changes or equivalent substitutions can be made to these features and embodiments without departing from the spirit and scope of this invention. Furthermore, under the teachings of this invention, these features and embodiments can be modified to adapt to specific circumstances without departing from the spirit and scope of this invention. Therefore, this invention is not limited to the specific embodiments disclosed herein, and all embodiments falling within the scope of the claims of this application are protected by this invention.

[0138] The contents not described in detail in this specification are common knowledge to those skilled in the art.

Claims

1. A method for generating the spatial location of parametric measurement points for experimental model design, characterized in that: Generate a straight line segment in three-dimensional space; Based on this straight line segment, a parameterized straight line segment group can be obtained by using a linear array or a circular array. Solve the parametric line segment group and the surface expression of the experimental model simultaneously to obtain the coordinates of all intersection points; Using the coordinates of all intersection points as the spatial locations of the measurement points, after the experimental model is formed, sensor holes are machined at all the spatial locations of the measurement points, and the sensors are installed in the sensor holes. The surface physical quantities at each measurement point of the model are obtained using the sensors.

2. The method for generating the spatial location of parameterized measuring points for experimental model design according to claim 1, characterized in that: When the scale of the experimental model changes, the spatial position of the generated measurement points is changed by adjusting the parameter values ​​of the linear array or circular array proportionally.

3. The method for generating the spatial location of parameterized measuring points for experimental model design according to claim 1, characterized in that: The linear array includes a single-direction linear array in Cartesian coordinate system and a two-direction linear array in Cartesian coordinate system.

4. The method for generating the spatial location of parameterized measuring points for experimental model design according to claim 3, characterized in that: The steps for obtaining the spatial position of a measuring point using a two-direction linear array of Cartesian coordinates include: Generate a straight line segment, x = x1, y = y1, z ∈ (Z). min Z max ); By performing a linear array along the x and y axes according to certain parameters, the following group of lines controlled by the x and y coordinates is obtained: x=x1,y=y1,z∈(Z min ,WITH max ) x=x2,y=y1,z∈(Z min ,WITH max ) …… x=x N ,y=y1,z∈(Z min ,Z max ) x=x1,y=y2,z∈(Z min ,Z max ) x=x2,y=y2,z∈(Z min ,Z max ) …… x=x N ,y=y2,z∈(Z min ,Z max ) …… x=x1,y=y N ,z∈(Z min ,Z max ) x=x2,y=y N ,z∈(Z min ,Z max ) …… x=x N ,y=y N ,z∈(Z min ,Z max ) Solving the system of equations for the straight line group and the experimental model surface z = f(x,y) simultaneously yields the coordinates of the intersection point: The spatial positions of the measuring points are obtained as (x1, y1, z1), (x2, y2, z2), (x3, y3, z3)...(x N ,y N ,z N ), where x1……x N ,y1……y N ,z min ,z max For parameters.

5. The method for generating the spatial location of parameterized measuring points for experimental model design according to claim 1, characterized in that: The circular array includes a single-direction array in cylindrical coordinates and a two-direction array in cylindrical coordinates.

6. The method for generating the spatial location of parameterized measuring points for experimental model design according to claim 5, characterized in that: The steps for obtaining the spatial position of a measuring point using a two-direction array in a cylindrical coordinate system include: Generate one line segment θ = θ1, Z = Z1, ρ ∈ (ρ min ,ρ max ); The following is a group of linear segments in an array controlled by parameters such as circumferential angle and normal: θ=θ1, Z=Z1, ρ∈(ρ min ,r max ); θ=θ2, Z=Z1, ρ∈(ρ min ,r max ); …… θ=θ N ,Z=Z1,ρ∈(ρ min ,r max ); θ=θ1, Z=Z2, ρ∈(ρ min ,r max ); θ=θ2, Z=Z2, ρ∈(ρ min ,r max ); …… θ=θ N ,Z=Z2,ρ∈(ρ min ,r max ); …… θ=θ1,Z=Z N ,ρ∈(ρ min ,r max ); θ=θ2,Z=Z N ,ρ∈(ρ min ,r max ); …… θ=θ N ,Z=Z N ,ρ∈(ρ min ,r max ); Solving the equations simultaneously for the group of line segments and the surface z = f(θ, ρ) of the experimental model yields the coordinates of the intersection point: …… The spatial positions of the measuring points are obtained as (θ1,z1,ρ1), (θ2,z2,ρ2), (θ3,z3,ρ3)……(θ N ,z N ,ρ N ), where θ1……θ N ,z 1…… z N ,ρ min ,ρ max For parameters.

7. The method for generating the spatial location of parameterized measuring points for experimental model design according to claim 1, characterized in that: The test model is an aircraft model, and the physical quantities include pressure, heat flow, and friction. In the pressure, heat flow, and friction point measurement test, the pressure, heat flow, and friction on the surface of the aircraft are obtained to provide wind tunnel test data for the aerodynamic shape design of the aircraft and optimize the aerodynamic shape design of the aircraft.

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