A method for calculating the projectile-receiving area of ​​a refined target model

Abstract

The present invention relates to a method for calculating the bullet-bearing area of ​​a refined target model, and belongs to the technical field of bullet-bearing area calculation. When the traditional method is used to calculate the bullet-bearing area, since the target model is approximately equivalent to a columnar structure, there may be a large deviation from the bullet-bearing area of ​​the real target, and the bullet-bearing area of ​​the target at different projection angles cannot be effectively calculated. In order to solve the above problems, it is necessary to establish a more refined three-dimensional geometric structure model of the target, but the traditional calculation method for the approximate equivalent model is no longer applicable, and it is necessary to find a bullet-bearing area calculation method suitable for a refined three-dimensional model. This scheme discretizes the projection plane into N sufficiently small square areas, constructs a projection ray with the center point of each square area, traverses the projection ray to see if it intersects with the target model, counts the number of intersecting rays, and multiplies it by the area of ​​the discretized single square area to obtain the bullet-bearing area of ​​the target at a specific projection angle.

Description

Technical Field

[0001] The invention belongs to the technical field of bullet-receiving area calculation, and in particular relates to a method for calculating the bullet-receiving area of ​​a refined target model. Background Art

[0002] When using traditional methods to calculate the bullet-damaging area, since the target model is approximately equivalent to a columnar structure, there may be a large deviation from the actual target's bullet-damaging area, and the target's bullet-damaging area at different projection angles cannot be effectively calculated. To solve the above problems, a more refined three-dimensional geometric structure model of the target needs to be established, but the traditional calculation method for the approximate equivalent model is no longer applicable, and a bullet-damaging area calculation method suitable for a refined three-dimensional model needs to be sought.

[0003] Therefore, at this stage, it is necessary to design a refined target model bullet-receiving area calculation method to solve the above problems. Summary of the invention

[0004] The purpose of the present invention is to provide a method for calculating the bullet-receiving area of ​​a refined target model, which is used to solve the technical problems existing in the above-mentioned prior art. When the traditional method is used to calculate the bullet-receiving area, since the target model is approximately equivalent to a columnar structure, there may be a large deviation from the bullet-receiving area of ​​the real target, and the bullet-receiving area of ​​the target at different projection angles cannot be effectively calculated. In order to solve the above problems, a more refined three-dimensional geometric structure model of the target needs to be established, but the traditional calculation method for the approximate equivalent model is no longer applicable, and a bullet-receiving area calculation method suitable for a refined three-dimensional model needs to be sought.

[0005] To achieve the above object, the technical solution of the present invention is:

[0006] A method for calculating the bullet-receiving area of ​​a refined target model comprises the following steps:

[0007] S1: Establish a refined 3D surface element model of the target and determine the projection plane position according to the projection angle and projection distance;

[0008] S2: According to the envelope radius of the target model, a target area is selected in the projection plane to ensure that the target area can cover the projection of the target model on the projection plane;

[0009] S3: discretize the target area into N square areas, and calculate and obtain the coordinates of the center points of the N square areas respectively;

[0010] S4: Establish projection rays with the coordinates of the center points of the N square areas as starting points, and the direction vector of the projection ray is perpendicular to the projection plane and points to the target model;

[0011] S5: traverse N projection rays to see if they intersect with the target model; for a single projection ray, if it intersects with any triangular face of the target model, it is considered to intersect with the target model;

[0012] S6: Count the number of rays that intersect the target model. The number of intersecting rays multiplied by the area of ​​a single square after discretization is the target's bullet-proof area at a specific projection angle.

[0013] Furthermore, the target area is a square area.

[0014] Furthermore, in step S5, the specific method for determining whether the projection ray intersects with the target model is as follows:

[0015] S501: According to the principle of determining a plane with three points, the coefficients of the equation of the plane formed by the three vertices of the triangular face element of the target model are calculated;

[0016] S502: normalizing the projection ray vector, and calculating the time required for the ray vertex to reach the target surface at a normalized speed based on the plane equation coefficients of the triangular face element, the ray direction vector, and the ray vertex coordinates;

[0017] S503: If the required time is greater than or equal to zero, the ray intersects the plane; otherwise, the ray does not intersect the plane, and the process returns to step S501 to continue determining the next triangular face element of the target model;

[0018] S504: If the ray intersects with the plane, calculate the intersection point of the ray on the plane; determine whether the intersection point is inside the triangular face element. If the intersection point is inside the triangular face element, it is considered that the ray intersects with the target model, exit the current ray judgment process, and enter the next ray judgment process; if the intersection point is not inside the triangular face element, return to step S501 and continue to judge the next triangular face element of the target model.

[0019] Furthermore, step S1 is as follows:

[0020] Establish a target refinement model and obtain the target envelope size: length, width, and height. Let L t Indicates the length of the target, W t Indicates the width of the target, H t Indicates the height of the target, satisfying L t ≥max(W t ,H t ); the target body coordinate system is o t x t y t z t , o t is the center point of the target, the ray With plane o t x tz t The angle between the rays is α, In the plane t x t z t The projection of x t The angle between the axes is β, where angle α and angle β are input values; along the ray Direction, at distance o t Point L t Determine the projection plane and ray vertical.

[0021] Furthermore, step S2 is as follows:

[0022] According to the envelope radius of the target model, a square area is selected in the projection plane, and the ray Intersection point o with the projection plane p is a square area S p The center point of the square area S p The side length is a; ensure that the square area can cover the projection of the target model on the projection plane, let a=1.1L t .

[0023] Furthermore, the calculation in step S3 to obtain the coordinates of the center points of the N square areas is as follows:

[0024] Create a square area S p The coordinate system is o p x p y p z p , where x p Axis and rays Coincidence; the specific calculation steps are:

[0025] a) Calculate point o p In the coordinate system o t x t y t z t Coordinates in The calculation formula is shown in formula (1);

[0026]

[0027] b) According to the square area S p The side length and the value of N can be used to calculate the center point o of each small square area. i ,i=1,2,…N 2 In the coordinate system o p x p y p z p Coordinates in According to formula (2), we can calculate o i ,i=1,2,…N 2 In the coordinate system o t x t y t z t Coordinates in

[0028]

[0029] Furthermore, in step S5, the specific method for determining whether the ray intersects with the target model is as follows:

[0030] S511, according to the principle of determining a plane with three points, the coefficients of the equation constituting the plane are calculated based on the three vertices of each triangular face element of the target model (A k B k C k D k )k=1,2,…n, n is the number of triangle elements of the target model;

[0031] S512, normalize the projection ray vector to obtain the projection ray direction vector v p , the calculation formula is shown in formula (3); based on the plane equation coefficient (A k B k C k D k )k=1,2,…n, ray direction vector v p , ray vertex coordinates Calculate the time required to reach the target surface from the vertex of the ray at a normalized speed. The calculation formula is shown in formula (4);

[0032]

[0033]

[0034] S513, if the required time t i If it is greater than or equal to zero, the ray intersects the plane; otherwise, the ray does not intersect the plane, and the process returns to step S511 to continue determining the next triangular face element of the target model;

[0035] S514. If the ray intersects the plane, calculate the coordinates of the intersection point of the ray on the plane The calculation formula is shown in formula (5); determine whether the intersection point is inside the triangle surface element. If the intersection point is inside the triangle surface element, it is considered that the ray intersects with the target model, and the current ray judgment process is exited and the next ray judgment process is entered; if the intersection point is not inside the triangle surface element, return to step S511 and continue to judge the next triangle surface element of the target model;

[0036]

[0037] A system for calculating the bullet-receiving area of ​​a refined target model adopts the above-mentioned method for calculating the bullet-receiving area of ​​a refined target model to calculate the bullet-receiving area of ​​a refined target model.

[0038] An electronic device, comprising:

[0039] processor;

[0040] a memory for storing processor-executable instructions;

[0041] The processor executes the executable instructions to implement the above-mentioned method for calculating the bullet-receiving area of ​​a refined target model.

[0042] A computer storage medium stores a computer program, which, when executed, executes the above-mentioned method for calculating the bullet-receiving area of ​​a refined target model.

[0043] Compared with the prior art, the present invention has the following beneficial effects:

[0044] One of the beneficial effects of this solution is that the present invention proposes a method for accurately calculating the target's bullet-receiving area based on parallel light projection. The projection plane is discretized into N sufficiently small square areas, and projection rays are constructed with the center point of each square area. The projection rays are traversed to see if they intersect with the target model, and the number of intersecting rays is counted, and multiplied by the area of ​​the discretized single square area to obtain the target's bullet-receiving area at a specific projection angle. BRIEF DESCRIPTION OF THE DRAWINGS

[0045] Figure 1 It is a schematic projection plane diagram of an embodiment of the present application.

[0046] Figure 2 It is a schematic diagram of projection rays according to an embodiment of the present application.

[0047] Figure 3 The figure is a flowchart of the method steps of an embodiment of the present application. DETAILED DESCRIPTION

[0048] Below in conjunction with the appended Figure 1 -Attached Figure 3 , the technical solutions in the embodiments of the present invention are clearly and completely described. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of them. 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.

[0049] When using traditional methods to calculate the bullet-damaging area, since the target model is approximately equivalent to a columnar structure, there may be a large deviation from the actual target's bullet-damaging area, and the target's bullet-damaging area at different projection angles cannot be effectively calculated. To solve the above problems, a more refined three-dimensional geometric structure model of the target needs to be established, but the traditional calculation method for the approximate equivalent model is no longer applicable, and a bullet-damaging area calculation method suitable for a refined three-dimensional model needs to be sought.

[0050] Example:

[0051] like Figure 3 As shown in the figure, a method for calculating the bullet-receiving area of ​​a refined target model is proposed.

[0052] 1) Establish a target refinement model to obtain the target envelope size: length, width, and height. Let L t Indicates the length of the target, W t Indicates the width of the target, H t Indicates the height of the target, satisfying L t ≥max(W t ,H t ). The target body coordinate system is o t x t y t z t , o t is the center point of the target, the ray With plane o t x t z t The angle between the rays is α, In the plane t x t z t The projection of x t The angle between the axes is β, where angle α and angle β are input values. Direction, at distance o t Point L t Determine the projection plane and ray Vertical. Figure 1 shown.

[0053] 2) According to the envelope radius of the target model, select a square area in the projection plane and let the ray Intersection point o with the projection plane p is a square area S p Let the square area S p The side length of is a. To ensure that the square area can cover the projection of the target model on the projection plane, let a = 1.1L t .

[0054] 3) The square area S pDiscretize into N sufficiently small uniform square areas. The number of N is related to the calculation accuracy of the bullet-receiving area. When the length of the target is constant, the higher the calculation accuracy is required, the larger the value of N is. For example, if a target is 10m long and the calculation accuracy of the bullet-receiving area is required to be 0.1m, then the value of N must be greater than 10m / 0.1m=100 to meet the calculation accuracy requirements.

[0055] 4) Calculate and obtain the coordinates of the center points of N square areas respectively. To facilitate calculation, establish a square area S p The coordinate system is o p x p y p z p ,like Figure 1 As shown, where x p Axis and rays The specific calculation steps are:

[0056] a) Calculate point o p In the coordinate system o t x t y t z t Coordinates in The calculation formula is shown in formula (1);

[0057]

[0058] b) According to the square area S p The side length and the value of N can be used to calculate the center point o of each small square area. i ,i=1,2,…N 2 In the coordinate system o p x p y p z p Coordinates in According to formula (2), we can calculate o i ,i=1,2,…N 2 In the coordinate system o t x t y t z t Coordinates in

[0059]

[0060] 5) Take the center point o of each of the N square regions as i ,i=1,2,…N 2 A projection ray is established for the starting point. The projection ray direction vector is perpendicular to the projection plane and points to the target model. Figure 2 shown.

[0061] 6) Check whether N projection rays intersect with the target model. For a single projection ray, if it intersects with any triangular face of the target model, it is considered to intersect with the target model. The specific method for determining whether the ray intersects with the target model is as follows:

[0062] a) According to the principle of determining a plane with three points, the coefficients of the equation constituting the plane are calculated based on the three vertices of each triangular face element of the target model (A k B k C k D k )k=1,2,…n, n is the number of triangle elements of the target model;

[0063] b) Normalize the projection ray vector to obtain the projection ray direction vector v p , the calculation formula is shown in formula (3). Based on the plane equation coefficient (A k B k C k D k )k=1,2,…n, ray direction vector v p , ray vertex coordinates Calculate the time required to reach the target surface from the vertex of the ray at a normalized speed. The calculation formula is shown in formula (4);

[0064]

[0065]

[0066] c) If the required time t i If it is greater than or equal to zero, the ray intersects the plane; otherwise, the ray does not intersect the plane, and the process returns to step a) to continue judging the next triangular face of the target model;

[0067] d) If the ray intersects the plane, calculate the coordinates of the intersection point of the ray on the plane The calculation formula is shown in formula (5). Determine whether the intersection point is inside the triangle surface element. If the intersection point is inside the triangle surface element, it is considered that the ray intersects with the target model, exit the current ray judgment process, and enter the next ray judgment process; if the intersection point is not inside the triangle surface element, return to step a) and continue to judge the next triangle surface element of the target model.

[0068]

[0069] 7) Count the number of rays that intersect the target model. The number of intersecting rays multiplied by the area of ​​a single discretized square is the target's bullet-receiving area at a specific projection angle.

[0070] The above are preferred embodiments of the present invention. Any changes made according to the technical solution of the present invention, as long as the resulting functions do not exceed the scope of the technical solution of the present invention, belong to the protection scope of the present invention.

Claims

1. A method for calculating the bullet-receiving area of ​​a refined target model, characterized in that: The following steps are involved: S1: Establish a refined 3D surface element model of the target and determine the projection plane position according to the projection angle and projection distance; Step S1 is as follows: Establish a target refinement model and obtain the target envelope size: length, width, and height. Let L t Indicates the length of the target, W t Indicates the width of the target, H t Indicates the height of the target, satisfying L t ≥max(W t ,H t ); the target body coordinate system is o t x t y t z t , o t is the center point of the target, the ray With plane o t x t z t The angle between the rays is α, In the plane t x t z t The projection of x t The angle between the axes is β, where angle α and angle β are input values; along the ray Direction, at distance o t Point L t Determine the projection plane and ray vertical; S2: According to the envelope radius of the target model, a target area is selected in the projection plane to ensure that the target area can cover the projection of the target model on the projection plane; S3: discretize the target area into N square areas, and calculate and obtain the coordinates of the center points of the N square areas respectively; S4: Establish projection rays with the coordinates of the center points of the N square areas as starting points, and the direction vector of the projection ray is perpendicular to the projection plane and points to the target model; S5: traverse N projection rays to see if they intersect with the target model; for a single projection ray, if it intersects with any triangular face of the target model, it is considered to intersect with the target model; S6: Count the number of rays that intersect the target model. The number of intersecting rays multiplied by the area of ​​a single square after discretization is the target's bullet-receiving area at a specific projection angle.

2. A method for calculating the bullet-receiving area of ​​a refined target model according to claim 1, characterized in that: The target area is a square area.

3. A method for calculating the bullet-receiving area of ​​a refined target model according to claim 1, characterized in that: In step S5, the specific method for determining whether the projection ray intersects with the target model is as follows: S501: According to the principle of determining a plane with three points, the coefficients of the equation of the plane formed by the three vertices of the triangular face element of the target model are calculated; S502: normalizing the projection ray vector, and calculating the time required for the ray vertex to reach the target surface at a normalized speed based on the plane equation coefficients of the triangular face element, the ray direction vector, and the ray vertex coordinates; S503: If the required time is greater than or equal to zero, the ray intersects the plane; Otherwise, the ray does not intersect the plane, and the process returns to step S501 to continue determining the next triangular face element of the target model; S504: If the ray intersects the plane, calculate the intersection point of the ray on the plane; Determine whether the intersection point is inside the triangle surface element. If the intersection point is inside the triangle surface element, it is considered that the ray intersects with the target model, and the current ray judgment process is exited and the next ray judgment process is entered; If the intersection point is not inside the triangle element, the process returns to step S501 and continues to determine the next triangle element of the target model.

4. A method for calculating the bullet-receiving area of ​​a refined target model according to claim 1, characterized in that: Step S2 is as follows: According to the envelope radius of the target model, a square area is selected in the projection plane, and the ray Intersection point o with the projection plane p is a square area S p The center point of the square area S p The side length is a; ensure that the square area can cover the projection of the target model on the projection plane, let a=1.1L t .

5. A method for calculating the bullet-receiving area of ​​a refined target model as claimed in claim 4, characterized in that: The calculation in step S3 to obtain the center point coordinates of the N square areas is as follows: Create a square area S p The coordinate system is o p x p y p z p , where x p Axis and rays Overlap; the specific calculation steps are: a) Calculate point o p In the coordinate system o t x t y t z t Coordinates in The calculation formula is shown in formula (1); b) According to the square area S p The side length and the value of N can be used to calculate the center point o of each small square area. i ,i=1,2,... N 2 In the coordinate system o p x p y p z p Coordinates in According to formula (2) It can be calculated that i ,i=1,2,... N 2 In the coordinate system o t x t y t z t Coordinates in 6. A method for calculating the bullet-receiving area of ​​a refined target model as claimed in claim 5, characterized in that: The specific method for determining whether the ray intersects with the target model in step S5 is: S511, according to the principle of determining a plane with three points, the coefficients of the equation constituting the plane are calculated based on the three vertices of each triangular face element of the target model (A k B k C k D k )k=1,2,...n, n is the number of triangle elements of the target model; S512, normalize the projection ray vector to obtain the projection ray direction vector v p , the calculation formula is shown in formula (3); based on the plane equation coefficients (Ak Bk Ck Dk) k = 1, 2, ... n, the ray direction vector v p , ray vertex coordinates Calculate the time required to reach the target surface from the vertex of the ray at a normalized speed. The calculation formula is shown in formula (4); S513, if the required time t i If it is greater than or equal to zero, the ray intersects the plane; otherwise, the ray does not intersect the plane, and the process returns to step S511 to continue determining the next triangular face element of the target model; S514. If the ray intersects the plane, calculate the coordinates of the intersection point of the ray on the plane The calculation formula is shown in formula (5); determine whether the intersection point is inside the triangle surface element. If the intersection point is inside the triangle surface element, it is considered that the ray intersects with the target model, exit the current ray judgment process, and enter the next ray judgment process; If the intersection point is not inside the triangle surface element, the process returns to step S511 and continues to determine the next triangle surface element of the target model; 7. A refined target model bullet-receiving area calculation system, characterized in that: The refined target model bullet-receiving area calculation method as described in any one of claims 1 to 6 is used to calculate the refined target model bullet-receiving area.

8. An electronic device, characterized in that: include: processor; a memory for storing processor-executable instructions; The processor executes the executable instructions to implement a method for calculating the bullet-receiving area of ​​a refined target model as described in any one of claims 1 to 6.

9. A computer storage medium, characterized in that The storage medium stores a computer program, which, when executed, executes a method for calculating the bullet-receiving area of ​​a refined target model as claimed in any one of claims 1 to 6.

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