Fragment intercept analysis method based on gravity effects
By constructing a ground coordinate system and discretizing fragment trajectories, and combining gravity and air resistance analysis, the calculation bias caused by neglecting gravity in traditional methods is solved, achieving efficient and accurate fragment intersection analysis and supporting refined damage assessment.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- GENERAL ENG RES INST CHINA ACAD OF ENG PHYSICS
- Filing Date
- 2023-11-17
- Publication Date
- 2026-07-21
AI Technical Summary
Traditional fragment intersection analysis methods ignore the influence of gravity, which leads to discrepancies between the calculated results and the actual results when the distance between the ammunition fragmentation field and the target is far, affecting the accuracy of refined damage assessment.
A ground coordinate system is constructed to obtain relevant information about the fragment and the target surface model. The flight trajectory of the fragment is analyzed considering gravity and air resistance, and it is discretized into multiple line segments. Invalid line segments are reduced from intersection calculations with the surface model through filters, while possible intersection cases are retained. Finally, the impact point of the fragment on the target surface model is calculated.
It improves the computational efficiency and accuracy of fragment cross-section analysis, provides efficient computational support for refined damage assessment, and reduces unnecessary computation.
Smart Images
Figure CN117494609B_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of computer technology, and in particular to a fragment cross-section analysis method based on the influence of gravity. Background Technology
[0002] In calculating the intersection of fragments and the target, traditional engineering calculation methods use the firing trajectory to determine the impact position of the fragments, generally neglecting the influence of gravity and assuming that the direction of the fragments' motion in the air is consistent with the direction of their initial velocity. When the intersection distance between the fragmentation field and the target is short, the influence of gravity on the fragment trajectory can be ignored; however, when the intersection distance is long, the influence of gravity on the fragment trajectory becomes significant. In this case, if the intersection calculation is performed using the initial velocity direction of the fragments and the target surface model, the calculated results will deviate from the actual results. For refined damage assessment, this deviation cannot be ignored. Summary of the Invention
[0003] The purpose of this invention is to design a fragment cross-section analysis method based on the influence of gravity in order to solve the above problems.
[0004] The present invention achieves the above objectives through the following technical solutions:
[0005] Methods for fragment cross-section analysis based on the influence of gravity include:
[0006] S1. Construct a ground coordinate system;
[0007] S2. Obtain relevant information about each fragment and the target surface model in the ground coordinate system;
[0008] S3. Analyze the flight trajectory of the current fragment based on gravity and air resistance, and according to relevant information of the fragment;
[0009] S4. Discretize the current fragment's flight trajectory into multiple line segments;
[0010] S5. Analyze the intersection results between the current fragment and the target surface element;
[0011] S6. Determine if the current fragment is the last fragment. If so, output the intersection of all fragments with the target surface model. Otherwise, set the next fragment as the current fragment and return to S3.
[0012] The beneficial effects of this invention are as follows: It considers the influence of gravity on the trajectory of fragments and introduces a filter to propose this analytical method. The actual flight trajectory of the fragments is discretized into multiple line segments. The impact point of the fragments on the target surface model is calculated by intersecting these line segments with the target surface elements. Directly solving this problem would increase the computational cost significantly compared to traditional shot trajectory methods. To reduce the calculation of invalid line segment intersections, a filter is introduced to eliminate a large number of invalid intersection calculations, retaining only a small number of possible intersections, ultimately calculating the target impact point information. This provides efficient computational support for damage assessment. Attached Figure Description
[0013] Figure 1 This is a schematic diagram of the flight trajectory discretization of the fragment intersection analysis method based on gravity influence of the present invention;
[0014] Figure 2 This is a schematic diagram of the line segment and surface element intersection filtering of the fragment intersection analysis method based on gravity influence of the present invention;
[0015] Figure 3 This is a schematic diagram of the ray intersection of the fragment cross-section analysis method based on the influence of gravity of the present invention. Detailed Implementation
[0016] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. The components of the embodiments of the present invention described and shown in the accompanying drawings can generally be arranged and designed in various different configurations.
[0017] Therefore, the following detailed description of the embodiments of the invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but merely to illustrate selected embodiments of the invention. All other embodiments obtained by those skilled in the art based on the embodiments of the invention without inventive effort are within the scope of protection of the invention.
[0018] It should be noted that similar labels and letters in the following figures indicate similar items. Therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures.
[0019] In the description of this invention, it should be understood that the terms "upper," "lower," "inner," "outer," "left," "right," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship commonly used when the product of this invention is in use, or the orientation or positional relationship commonly understood by those skilled in the art. They are only used to facilitate the description of this invention and to simplify the description, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.
[0020] Furthermore, the terms "first," "second," etc., are used only to distinguish descriptions and should not be interpreted as indicating or implying relative importance.
[0021] In the description of this invention, it should also be noted that, unless otherwise explicitly specified and limited, terms such as "set" and "connection" should be interpreted broadly. For example, "connection" can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium; it can be a connection within two components. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.
[0022] The specific embodiments of the present invention will now be described in detail with reference to the accompanying drawings.
[0023] Methods for fragment cross-section analysis based on the influence of gravity include:
[0024] S1. Construct a ground coordinate system.
[0025] S2. Obtain the relevant information of each fragment and the target surface model in the ground coordinate system. The relevant information of each fragment in the ground coordinate system includes the initial position coordinates and velocity vector. The relevant information of the target surface model in the ground coordinate system includes the coordinates of all target surface elements of the target surface model.
[0026] S3. Analyze the current flight trajectory of the fragment based on gravity and air resistance, and according to relevant fragment information; specifically, based on the initial mass of the fragment... and initial velocity The flight trajectory of the fragment is calculated and represented as:
[0027] ;
[0028] in, , , for The velocity components of the fragment on the three axes of the ground coordinate system at any given moment. , , for The position coordinates of the fragment in the ground coordinate system at any given time. , , for The component of the gravitational force acting on the fragment in the ground coordinate system at any given moment. , , for The component of air resistance experienced by the fragment on the ground coordinate system at any given moment.
[0029] S4. Discretize the current fragment's trajectory into multiple line segments; specifically: divide the current fragment's trajectory into different time periods according to time sequence, and connect the beginning and end of the trajectory within each time period to discretize the current fragment's trajectory into multiple line segments, such as... Figure 1 As shown.
[0030] S5. Analyze the intersection results between the current fragment and the target surface element; specifically including:
[0031] ① Decompose the current line segment and target surface element of the current fragment into line-plane elements, such as... Figure 2 As shown;
[0032] ② Analyze whether the current line segment of the current fragment intersects with the target surface element according to the first and second conditions. If the first or second condition is met, the current line segment of the current fragment intersects with the target surface element. Then the target surface element is added to the list of potential intersecting surface elements corresponding to the line segment and proceeds to ④. Otherwise, proceed to ③.
[0033] The first condition is:
[0034] ;
[0035] The second condition is:
[0036] ;
[0037] In the ground coordinate system, the two endpoints of the line segment and the three vertices of the target surface element are... The coordinates of the projection point on the axis are represented as , , , , ;
[0038] ③ Determine whether the current line segment of the current fragment is the last line segment of the current fragment. If so, the current fragment does not intersect with the target surface model and proceeds directly to S6; otherwise, make the next line segment of the current fragment the current line segment and return to ②.
[0039] ④ For the current line segment with potential intersecting elements, extend the current line segment along the trajectory direction to establish a ray, such as... Figure 3 As shown;
[0040] ⑤ Determine whether the current ray intersects with the current target surface in the potential intersecting surface list based on the third condition, and whether the intersection point is inside the current target surface. If the condition is met, the current fragment intersects with the target surface model and directly enters S6; otherwise, enter ⑥.
[0041] The third condition is:
[0042] ;
[0043] in, , , , These are the coefficients of the equation of the plane containing the triangular element. The time it takes for the ray to reach the plane containing the triangular element. The point where the ray intersects the plane containing the triangular element. coordinates , , , Triangular face elements , , , The area;
[0044] ⑥ Determine if the current target surface is the last target surface in the list of intersecting surfaces. If so, the current ray does not intersect with the target surface model and proceeds to ⑦. Otherwise, the next target surface is taken as the current target surface and the process returns to ⑤.
[0045] ⑦ Determine if the current ray is the last ray. If so, the current fragment does not intersect with the target surface model and proceeds directly to S6; otherwise, make the next ray the current ray and return to ⑤.
[0046] S6. Determine if the current fragment is the last fragment. If so, output the intersection of all fragments with the target surface model. Otherwise, set the next fragment as the current fragment and return to S3.
[0047] For refined damage assessment, the difference between calculated and actual results cannot be ignored. To address this issue, this analysis method considers the influence of gravity on fragment trajectory and introduces a filter. The actual fragment trajectory is discretized into multiple line segments. The impact point of the fragment on the target surface model is calculated by intersecting these line segments with the surface elements. Directly solving this method would be significantly more computationally intensive than traditional shot trajectory methods. To reduce invalid line segment intersection calculations, a filter is introduced to eliminate a large number of invalid intersection cases, retaining only a small number of possible intersection cases. This ultimately yields the target impact point information, providing efficient computational support for damage assessment.
[0048] The technical solutions of the present invention are not limited to the specific embodiments described above. Any technical modifications made in accordance with the technical solutions of the present invention fall within the protection scope of the present invention.
Claims
1. A fragment cross-section analysis method based on the influence of gravity, characterized in that, include: S1. Construct a ground coordinate system; S2. Obtain relevant information about each fragment and the target surface model in the ground coordinate system; S3. Analyze the flight trajectory of the current fragment based on gravity and air resistance, and according to relevant information of the fragment; S4. Discretize the current fragment's flight trajectory into multiple line segments; S5. Analyze the intersection results between the current fragment and the target surface element; specifically including: ① Separate the current line segment and target surface element of the current fragment into line-plane elements; ② Analyze whether the current line segment of the current fragment intersects with the target surface element. If yes, add the target surface element to the list of potential intersecting surface elements corresponding to the line segment and proceed to ④. Otherwise, proceed to ③. Specifically, analyze whether the current line segment of the current fragment intersects with the target surface element according to the first and second conditions. When the first or second condition is met, the current line segment of the current fragment intersects with the target surface element. The first condition is: ； The second condition is: ； In the ground coordinate system, the two endpoints of the line segment and the three vertices of the target surface element are... The coordinates of the projection point on the axis are represented as , , , , ; ③ Determine whether the current line segment of the current fragment is the last line segment of the current fragment. If so, the current fragment does not intersect with the target surface model and proceeds directly to S6; otherwise, make the next line segment of the current fragment the current line segment and return to ②. ④ For the current line segment with potential intersecting elements, extend the current line segment along the trajectory direction to establish a ray; ⑤ Determine whether the current ray intersects with the current target surface in the potential intersecting surface list, and whether the intersection point is inside the current target surface. If the condition is met, the current fragment intersects with the target surface model and directly enters S6; otherwise, enter ⑥. Specifically, determine whether the current ray intersects with the current target surface in the potential intersecting surface list, and whether the intersection point is inside the current target surface, based on the third condition. The third condition is: ； in, , , , These are the coefficients of the equation of the plane containing the triangular element. The time it takes for the ray to reach the plane containing the triangular element. The point where the ray intersects the plane containing the triangular element. coordinates , , , Triangular face elements , , , area, , , for The position coordinates of the fragment in the ground coordinate system at any given moment; ⑥ Determine if the current target surface is the last target surface in the list of intersecting surfaces. If so, the current ray does not intersect with the target surface model and proceeds to ⑦. Otherwise, the next target surface is taken as the current target surface and the process returns to ⑤. ⑦ Determine if the current ray is the last ray. If it is, the current fragment does not intersect with the target surface model and proceeds directly to S6; otherwise, make the next ray the current ray and return to ⑤. S6. Determine if the current fragment is the last fragment. If so, output the intersection of all fragments with the target surface model. Otherwise, set the next fragment as the current fragment and return to S3.
2. The fragment cross-section analysis method based on gravity influence according to claim 1, characterized in that, The relevant information for each fragment in the ground coordinate system includes its initial position coordinates and velocity vector, while the relevant information for the target element model in the ground coordinate system includes the coordinates of all target elements in the target element model.
3. The fragment cross-section analysis method based on gravity influence according to claim 1, characterized in that, Based on the initial mass of the fragment and initial velocity The flight trajectory of the fragment is calculated and represented as: ； in, , , for The velocity components of the fragment on the three axes of the ground coordinate system at any given moment. , , for The position coordinates of the fragment in the ground coordinate system at any given time. , , for The component of the gravitational force acting on the fragment in the ground coordinate system at any given moment. , , for The component of air resistance experienced by the fragment on the ground coordinate system at any given moment.
4. The fragment cross-section analysis method based on gravity influence according to claim 1, characterized in that, In S4, the flight trajectory of the current fragment is divided into different time periods according to the time sequence. By connecting the beginning and end of the flight trajectories within the time period, the flight trajectory of the current fragment is discretized into multiple line segments.