Bird body high-speed impact bird cutting amount calculation method and system based on optical image analysis

Abstract

The present invention belongs to the technical field of foreign object impact on composite blades of aircraft engines, and specifically discloses a method and system for calculating the amount of bird cuts caused by high-speed impact of a bird body based on optical image analysis. The method comprises the following steps: obtaining an image of a birdshot impact fixture, and marking feature points of the image of the birdshot impact fixture to obtain a marked image; obtaining the speed direction line of the birdshot flight, the bird cut point, and the spatial position of the birdshot when the bird hits based on the marked image and the equal image pixel method; and then calculating the amount of bird cuts to complete the calculation of the amount of bird cuts caused by high-speed impact of a bird body. The present invention solves the problem that the prior art cannot accurately calculate the amount of bird cuts, is simple to operate, helps to better understand the impact of bird strikes on aircraft structures, and provides a basis for improving aircraft design.

Description

Technical Field

[0001] The invention belongs to the technical field of foreign object impact on composite material blades of aircraft engines, and in particular relates to a method and system for calculating bird cutting amount due to high-speed impact of a bird body based on optical image analysis. Background Art

[0002] Bird strike, also known as bird hit, refers to an incident in which an aircraft is hit head-on by a bird when flying at low altitude or approaching landing, causing local damage. Later, it was expanded to incidents in which birds collide with high-speed trains, cars, artificial buildings and other facilities, causing damage to objects and injuries to birds.

[0003] Resin-based composite materials (composite materials for short) have the advantages of high specific strength, high specific stiffness, integral molding and designability, and are one of the most widely used lightweight materials. At present, major engine manufacturers have used resin-based composite materials on a large scale in the fan blades and fan casing structures of civil high bypass ratio engines. During service, composite blades are susceptible to catastrophic damage caused by bird impacts, resulting in aircraft destruction and loss of life. Bird strikes during the rotation of blades are actually a high-speed bird cutting process at the leading edge. The bird body is sharply cut into two or more parts. Due to the residual speed, the cut bird body will continue to fly and hit other parts of the engine, causing further damage.

[0004] In order to study the bird strike resistance of composite blades, it is necessary to carry out simulated bird strike tests for evaluation. The realization of bird cutting and the accurate calculation of the amount of bird cutting in the test are of great guiding significance for improving the test accuracy and analyzing the law of bird strike damage. However, the existing technology relies on empirical formulas when calculating the amount of bird cutting, or does not consider the percentage of bird cutting, which cannot accurately reflect the actual situation.

[0005] One solution in the prior art combines an air cannon and a wedge-shaped Hopkinson bar to solve the problem in the existing engine fan blade bird strike research that the bird-cutting load history cannot be accurately measured due to the coupling of the dynamic deformation of the bird body and the blade deformation. However, the bird-cutting position of this method is fixed, and the influence of the amount of bird-cutting is not considered. Another solution is to calculate the bird-cutting volume by firing simulated bird bullets to impact the blade test piece, and the sensor identifies the position and speed of the bird bullets. However, this method is limited by the sampling frequency of the sensor, and it is the identification of the bird bullets at the moment of impact, which has a certain error and is easily disturbed by broken bird bullets.

[0006] In general, the above disclosed technical solutions and devices cannot simultaneously meet the requirements of monitoring the bird cutting process and high-precision calculation of the bird cutting amount, while the above parameters have a direct impact on the study of the laws of high-speed impact tests on bird bodies. Summary of the invention

[0007] The purpose of the present invention is to solve the problem that the prior art cannot accurately calculate the amount of bird cut, and proposes a method and system for calculating the amount of bird cut by high-speed impact of a bird body based on optical image analysis.

[0008] The technical scheme of the present invention is as follows: In the first aspect, a method for calculating the amount of bird cut by high-speed impact of a bird body based on optical image analysis includes two situations: an ideal situation where the bird bullet posture is perpendicular to the fixture without deflection and a situation where the bird bullet rolls and yaws during flight:

[0009] In the ideal case where the birdshot attitude is perpendicular to the fixture without deflection, the method includes the following steps:

[0010] S101. Obtain two frames of images before the birdshot hits the fixture, and mark the feature points of the two frames of images respectively to obtain the marked points and the two frames of images after marking;

[0011] S102. Connect and extend the same marked points in the two marked frames to obtain the speed direction line of the birdshot flight;

[0012] S103. Calculate the bird cutting point based on the marked image and pixel ratio relationship;

[0013] S104. Draw a perpendicular line to the velocity direction line at the marked point, and translate the perpendicular line along the velocity line to intersect the bird-cutting point, record the intersection of the perpendicular line and the velocity direction line as the position of the marked point at the time of impact, and thereby obtain the spatial position of the birdshot at the time of bird impact;

[0014] S105. Based on the speed direction line of the birdshot flight, the bird cutting point and the spatial position of the birdshot when the bird hits, the bird cutting amount is calculated, and the bird cutting amount calculation of the high-speed impact of the bird body is completed;

[0015] When the birdshot has a rolling and yaw attitude during flight, the method comprises the following steps:

[0016] S201. Acquire two frames of images before the birdshot hits the fixture, and mark the feature points of the two frames of images respectively to obtain the marked points, the two frames of images after marking, and the outline of the birdshot in the second frame of image;

[0017] S202. Select the same marked points in the two marked frames to connect and extend them to obtain the speed direction line of the birdshot flight;

[0018] S203. Calculate the bird cutting point based on the marked image and pixel ratio relationship;

[0019] S204. The birdshot outline in the second frame image is proportionally shifted along the velocity direction line until the leading edge of the birdshot hits the bird cutting point. At this time, the birdshot is divided into two parts by the velocity direction line, and the bird cutting amount is calculated based on the proportional relationship between the birdshot and the part of the birdshot divided by the velocity direction line.

[0020] The beneficial effects of the present invention are:

[0021] The present invention aims at the ideal situation that the birdshot attitude is perpendicular to the fixture without deflection and the situation that the birdshot rolls and yaws during flight. By marking the feature points of two frames of images before the birdshot hits the fixture, the accurate calculation of the birdshot amount can be achieved based on the pixel ratio relationship, which helps to better understand the impact of bird strikes on aircraft structures and provide a basis for improving aircraft design.

[0022] Preferably, the step S101 specifically includes the following steps:

[0023] Using high-speed cameras to monitor the birdshot impact process;

[0024] The two frames of images before the birdshot hits the fixture are captured from the high-speed camera, and are projected on a plane, and the outline of the birdshot in the two frames of images is drawn by pasting grid lines;

[0025] The birdshot contours are marked with feature points on the grid lines.

[0026] Preferably, the second frame of the two frames of images before the birdshot hits the fixture in step S201 is an image just before the birdshot hits the fixture, and the birdshot has a constant posture from the frame before the impact until the moment of impacting the fixture, and the roll and yaw of the birdshot are based on the center point as the origin;

[0027] The step S201 specifically includes the following steps:

[0028] Using high-speed cameras to monitor the birdshot impact process;

[0029] The first two frames of images of the birdshot hitting the fixture are captured from the high-speed camera, and the images are projected on a plane, and the outline of the birdshot in the second frame is drawn by pasting grid lines;

[0030] Mark feature points on the grid lines.

[0031] Preferably, the marking point in step S202 is a marking point close to the exact center of the birdshot. At this time, the birdshot in the two frames has different global spatial states. Due to the roll and yaw of the birdshot in the second frame, the projection of the birdshot is smaller than the original birdshot outline.

[0032] Preferably, the step S103 and the step S203 specifically include the following sub-steps:

[0033] A scale is pasted on the side boundary line of the fixture, and a high-speed camera is used to monitor the birdshot impact process to obtain the bird strike point;

[0034] The height of the bird strike point from the upper edge of the typical blade part is measured by a ruler ;

[0035] Measure the height from the upper edge of the typical blade to the top of the fixture using a scale ;

[0036] Based on the height of the bird strike point from the upper edge of the typical blade part , Height from the upper edge of the typical blade to the top of the fixture The bird-cutting point is calculated based on the pixel ratio relationship in the same frame image.

[0037] Preferably, the height of the bird strike point from the upper edge of the blade typical part , Height from the upper edge of the typical blade to the top of the fixture The bird-cutting point is calculated based on the pixel ratio relationship in the same frame image, which specifically includes the following steps:

[0038] According to the height of the bird strike point from the upper edge of the typical blade and the height from the upper edge of the typical blade to the top of the fixture , calculate the actual distance between the bird impact point and the upper edge of the fixture, and the calculation formula is:

[0039]

[0040] in, Indicates the actual distance between the bird impact point and the upper edge of the fixture;

[0041] According to the pixel ratio in the same frame image, the actual distance from the upper edge of the fixture to the root of the fixture is , the distance between pixels in the photo is , then the proportional conversion relationship of the fixture boundary line is for:

[0042] ;

[0043] According to the same conversion ratio on the same boundary line, the pixel distance between the impact point on the fixture boundary line and the upper edge of the fixture is The expression formula is:

[0044]

[0045] According to the pixel distance between the impact point and the upper edge of the fixture on the fixture boundary line You can get the bird cutting point.

[0046] Preferably, the step S105 specifically includes the following steps:

[0047] The birdshot outer contour line is drawn along the pasted grid line at the center of the birdshot spatial position in the image when the bird hits. The pixel length of the birdshot outer contour line is , the birdshot outer contour is divided into and Two parts;

[0048] Place the birdshot outside the outline The part starts from the intersection of the birdshot outer contour line and the velocity direction line, and moves along the velocity direction line to the spatial position of the birdshot when the bird hits the velocity direction line while maintaining the segmentation ratio. Then the birdshot outer contour line is segmented again by the bird-cutting point, and the measurement is performed. The length of the part of the segment divided by the cut point ;

[0049] Based on the pixel length of the birdshot outer contour and The length of the part of the segment divided by the cut point , you can get the amount of bird cut , and its calculation formula is:

[0050] ;

[0051] Repeat the above steps, take at least three birdshot outer contour lines on the entire birdshot to calculate the bird cut amount, and take the average to obtain the final bird cut amount, which is calculated as follows:

[0052]

[0053] in, It indicates the amount of bird cut when the birdshot attitude is perpendicular to the ideal condition with no deflection of the fixture. , and Represents the first, second and The amount of bird cuts calculated is Indicates the total number of selected contours.

[0054] Preferably, the calculation formula of the bird cutting amount in step S204 is:

[0055]

[0056] in, It indicates the amount of bird cut when the birdshot has a rolling and yaw attitude during flight. It means birdshot. Birdshot The part divided by the velocity direction line.

[0057] The beneficial effects of the above preferred solution are:

[0058] 1. By pasting grid lines to make the outline of the birdshot and marking the feature points of the birdshot outline on the grid lines, the flight trajectory and speed direction line of the birdshot can be accurately obtained, and the operation is simple.

[0059] 2. Based on the pixel ratio in the same frame image and the pixel length of the birdshot outer contour line and The length of the part of the segment divided by the cut point The proportional relationship calculation can accurately obtain the bird cutting point and bird cutting amount of the bird body's high-speed impact, while accurately reflecting the actual situation without the need for complicated calculation process.

[0060] In a second aspect, a system for calculating the amount of bird cuts caused by high-speed impact of a bird body based on optical image analysis is provided. The system comprises a processor, and the processor is used to execute the method for calculating the amount of bird cuts caused by high-speed impact of a bird body based on optical image analysis as described in the first aspect.

[0061] In a third aspect, a computer-readable storage medium stores computer instructions. In response to a computer reading the computer instructions in the storage medium, the computer executes the method for calculating the amount of bird cuts caused by high-speed impact of a bird body based on optical image analysis as described in the first aspect. BRIEF DESCRIPTION OF THE DRAWINGS

[0062] Figure 1 The flowchart of the method for calculating the bird cutting amount by high-speed impact of a bird body based on optical image analysis is shown in the ideal situation that the birdshot posture is perpendicular to the fixture without deflection provided in Example 1 of the present invention.

[0063] Figure 2 The figure shows the principle diagram of bird cut calculation when the birdshot posture provided in the first embodiment of the present invention is perpendicular to the ideal situation of the fixture without deflection.

[0064] Figure 3 The figure shows a flow chart of a method for calculating the amount of bird cuts caused by high-speed impact of a bird body based on optical image analysis when the birdbomb provided in Example 1 of the present invention has a rolling and yaw attitude during flight.

[0065] Figure 4 The figure shows the principle diagram of calculating the bird cut amount when the bird bomb provided in the first embodiment of the present invention has a rolling and yaw attitude during flight.

[0066] Figure 5 Shown is a schematic diagram of the birdshot marking provided in Example 1 of the present invention.

[0067] Figure 6The height of the bird strike point from the upper edge of the blade typical part provided in Example 1 of the present invention is shown as follows: And the distance from the upper edge of the typical blade to the top of the fixture Calculation diagram. DETAILED DESCRIPTION

[0068] Now, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings. It should be understood that the embodiments shown and described in the accompanying drawings are only exemplary and are intended to explain the principles and spirit of the present invention, rather than to limit the scope of the present invention.

[0069] Before describing the specific embodiments of the present invention, in order to make the scheme of the present invention more clear and complete, the definitions of key terms appearing in the present invention are first explained:

[0070] Soft impact: When an aircraft engine is in flight, the composite fan blades are in high-speed operation, which can easily inhale foreign objects and collide with them, thus damaging the blades. When the foreign object is a material with a lower hardness, such as a bird, it is usually called a "soft" impact.

[0071] Typical blade parts: refers to the equivalent flat plate parts that simulate engine blades.

[0072] Bird cutting and bird cutting amount: The leading edge of the engine blade cuts the bird body sucked in by the engine inlet at a certain angle. After being cut, the bird body will be separated into two parts and continue to hit the surface of the typical part of the blade and other parts, which is called "bird cutting". The percentage of the part of the bird body that hits the surface of the typical part of the blade after being cut is called "bird cutting amount".

[0073] Bird strike height: refers to the vertical distance between the position where the bird body strikes the tooling when being cut and the upper edge of the typical blade part.

[0074] Embodiment 1:

[0075] A method for calculating the amount of bird cut by high-speed impact of a bird body based on optical image analysis includes two cases: the ideal case where the bird bullet is perpendicular to the fixture without deflection and the case where the bird bullet rolls and yaws during flight.

[0076] like Figure 1 As shown, when the birdshot posture is perpendicular to the ideal condition of no deflection of the fixture, the method includes the following steps:

[0077] S101. Obtain two frames of images before the birdshot hits the fixture, and mark the feature points of the two frames of images respectively to obtain the marked points and the two frames of images after marking;

[0078] S102. Connect and extend the same marked points in the two marked frames to obtain the speed direction line of the birdshot flight;

[0079] S103. Calculate the bird cutting point based on the marked image and pixel ratio relationship;

[0080] S104. Draw a perpendicular line to the velocity direction line at the marked point, and translate the perpendicular line along the velocity line to intersect the bird-cutting point, record the intersection of the perpendicular line and the velocity direction line as the position of the marked point at the time of impact, and thereby obtain the spatial position of the birdshot at the time of bird impact;

[0081] S105. Based on the speed direction line of the birdshot flight, the bird cutting point and the spatial position of the birdshot when the bird hits, the bird cutting amount is calculated, and the bird cutting amount calculation of the high-speed impact of the bird body is completed, which specifically includes the following steps:

[0082] like Figure 2 As shown in the figure, the birdshot outer contour line is drawn along the pasted grid line at the center of the birdshot spatial position in the image when the bird hits. The pixel length of the birdshot outer contour line is , the birdshot outer contour is divided into and Two parts;

[0083] Place the birdshot outside the outline The part starts from the intersection of the birdshot outer contour line and the velocity direction line, and moves along the velocity direction line to the spatial position of the birdshot when the bird hits the velocity direction line while maintaining the segmentation ratio. Then the birdshot outer contour line is segmented again by the bird-cutting point, and the measurement is performed. The length of the part of the segment divided by the cut point ;

[0084] Based on the pixel length of the birdshot outer contour and The length of the part of the segment divided by the cut point , you can get the amount of bird cut , and its calculation formula is:

[0085] ;

[0086] Repeat the above steps, take at least three birdshot outer contour lines on the entire birdshot to calculate the bird cut amount, and take the average to obtain the final bird cut amount, which is calculated as follows:

[0087]

[0088] in, It indicates the amount of bird cut when the birdshot attitude is perpendicular to the ideal condition with no deflection of the fixture. , and Represents the first, second and The amount of bird cuts calculated is Indicates the total number of selected contours.

[0089] like Figure 3 As shown, when the birdshot has a rolling and yaw attitude during flight, the method includes the following steps:

[0090] S201. Obtain two frames of images before the birdshot hits the fixture, the first frame of the image is flight point 1, and the second frame of the image is flight point 2, and mark the feature points of the two frames of images respectively to obtain the marked points, the two frames of images after marking, and the birdshot contour of flight point 2;

[0091] The second frame of the two frames of images before the birdshot hits the fixture is an image just before the birdshot hits the fixture. The birdshot has a constant attitude from the frame before the impact until the moment of impacting the fixture, and the roll and yaw of the birdshot are based on the center point as the origin.

[0092] S202. Select the same marked points in the two marked frames to connect and extend them to obtain the speed direction line of the birdshot flight;

[0093] The marking point is a marking point close to the exact center of the birdshot to avoid errors caused by roll and yaw. At this time, the birdshot in the two frames has different global spatial states. Due to roll and yaw, the projection of the birdshot in the second frame is smaller than the original birdshot outline. Here, the spatial depiction before the impact is enlarged for easy understanding, which is actually very close to the fixture.

[0094] S203. Calculate the bird cutting point based on the marked image and pixel ratio relationship;

[0095] S204. Figure 4 As shown in FIG. 1 , the birdshot outline in the second frame image is proportionally translated along the velocity direction line until the leading edge of the birdshot hits the bird cutting point. At this time, the birdshot is divided into two parts by the velocity direction line. Then, the bird cutting amount is calculated based on the proportional relationship between the birdshot and the part of the birdshot divided by the velocity direction line. The calculation formula of the bird cutting amount is:

[0096]

[0097] in, It indicates the amount of bird cut when the birdshot has a rolling and yaw attitude during flight. It means birdshot. Birdshot The part divided by the velocity direction line.

[0098] In this embodiment, the step S101 and the step S201 specifically include the following steps:

[0099] The birdshot impact process is monitored by a high-speed camera. In this embodiment, six high-speed cameras are used to monitor the birdshot impact process, namely: a front camera, used to capture the birdshot impact process and detect whether there is any abnormality in the birdshot exiting the barrel; a side camera, used to capture the flight path of the birdshot, with a narrow and long field of view, and the camera height is consistent with the birdshot height, and the impact velocity measurement is completed according to the pixel analysis method; a top-mounted camera, used to capture the bird body being cut by the fixture, and when placed, the vertical line of the side of the fixture in the top-down state can be as large as possible to identify the area of ​​the vertical line that can be identified, so as to facilitate the subsequent calculation of the amount of bird cut according to the image method; two cameras directly behind, used to calculate the out-of-plane deformation field of the typical blade part during the impact process, and their placement position is based on the center line of the typical blade part to keep it as symmetrical as possible, and at the same time, the placement position and shooting field of view are adjusted to ensure that the displacement field data of the entire typical blade part can be obtained; a side rear camera, used to capture the height position of the bird body hitting the fixture, and its placement angle is as perpendicular to the fixture surface as possible to identify the scale position of the impact height with higher accuracy;

[0100] The first two frames of images before the birdshot hits the fixture are intercepted from the high-speed camera, and a plane projection is made, and the outline of the birdshot in the two frames of images is made by pasting grid lines, wherein the fixture is used to fix the typical blade part, and the fixture is "L" shaped;

[0101] like Figure 5 As shown, the birdshot outline is marked with characteristic points on the grid lines, namely, birdshot markings, and different characteristic points are marked with different marks, such as star-shaped, circular and cross-shaped marks.

[0102] In this embodiment, the step S103 and the step S203 specifically include the following sub-steps:

[0103] A ruler is pasted on the side boundary line of the fixture, the starting end of the ruler is aligned with the upper edge of the typical blade piece held by the fixture and pasted downward, and a high-speed camera is used to monitor the birdshot impact process to obtain the bird strike point;

[0104] The height of the bird strike point from the upper edge of the typical blade part is measured by a ruler and the height from the upper edge of the typical blade to the top of the fixture , which is the bird strike height. The calculation of the bird strike height needs to be combined with the side camera and the side rear camera: Figure 6 As shown in Figure 1, first observe the leading edge line of the bird body that first contacts the fixture from the speed camera, as shown in Figure 1. Figure 6 The number 4 mark is in the middle; then, observe the intersection of the number 4 mark extension line and the mark line on the fixture in the side and rear camera field of view, and add the distance from the upper edge of the typical blade part to the mark line, which is the distance from the birdshot impact point to the upper edge of the typical blade part, that is, the bird strike height.

[0105] Based on the height of the bird strike point from the upper edge of the typical blade part , Height from the upper edge of the typical blade to the top of the fixture The bird-cutting point is calculated based on the pixel ratio relationship in the same frame image, which specifically includes the following steps:

[0106] According to the height of the bird strike point from the upper edge of the typical blade and the height from the upper edge of the typical blade to the top of the fixture , calculate the actual distance between the bird impact point and the upper edge of the fixture, and the calculation formula is:

[0107]

[0108] in, Indicates the actual distance between the bird impact point and the upper edge of the fixture;

[0109] According to the pixel ratio in the same frame image, the actual distance from the upper edge of the fixture to the root of the fixture is , the distance between pixels in the photo is , then the proportional conversion relationship of the fixture boundary line is for:

[0110] ;

[0111] According to the same conversion ratio on the same boundary line, the pixel distance between the impact point on the fixture boundary line and the upper edge of the fixture is The expression formula is:

[0112]

[0113] According to the pixel distance between the impact point and the upper edge of the fixture on the fixture boundary line You can get the bird cutting point.

[0114] Repeat the above steps, take at least three birdshot outer contour lines on the entire birdshot to calculate the bird cut amount, and take the average to obtain the final bird cut amount, which is calculated as follows:

[0115]

[0116] in, It indicates the amount of bird cut when the birdshot attitude is perpendicular to the ideal condition with no deflection of the fixture. , and Represents the first, second and The amount of bird cuts calculated is Indicates the total number of selected contours.

[0117] Embodiment 2:

[0118] On the basis of Example 1, this example provides a bird body high-speed impact bird cutting amount calculation system based on optical image analysis, which can be used to implement the bird body high-speed impact bird cutting amount calculation method based on optical image analysis as described in Example 1.

[0119] In this embodiment, the system may be an electronic device, comprising a memory, a processor, and a computer program stored in the memory and running on the processor, and the processor executes the program to implement part or all of the steps of the method for calculating the amount of bird cuts caused by high-speed impact of a bird body based on optical image analysis as described in Example 1.

[0120] In this embodiment, the electronic device may include: a processor, a memory, a bus and a communication interface. The processor, the communication interface and the memory are connected via a bus. The memory stores a computer program that can be run on the processor. When the processor runs the computer program, it executes part or all of the steps of the method for calculating the amount of bird cuts caused by high-speed impact of a bird body based on optical image analysis provided in the aforementioned embodiment 1 of the present application.

[0121] The system in the embodiment of the present invention can also be a computer-readable storage medium, which stores a computer program. When the computer program is executed, some or all steps of the method for calculating the amount of bird cuts caused by high-speed impact of a bird body based on optical image analysis as described in Example 1 are implemented.

[0122] The program code for implementing the method of the present invention can be written in any combination of one or more programming languages. These program codes can be provided to a processor or controller of a general-purpose computer, a special-purpose computer or other programmable data processing device, so that the program code, when executed by the processor or controller, enables the functions / operations specified in the flow chart and / or block diagram to be implemented. The program code can be executed entirely on the machine, partially on the machine, partially on the machine as a stand-alone software package and partially on a remote machine, or entirely on a remote machine or server.

[0123] In the context of the present invention, a machine-readable medium may be a tangible medium that may contain or store a program for use by or in conjunction with an instruction execution system, device, or equipment. A machine-readable medium may be a machine-readable signal medium or a machine-readable storage medium. A machine-readable medium may include, but is not limited to, electronic, magnetic, optical, electromagnetic, infrared, or semiconductor systems, devices, or equipment, or any suitable combination of the foregoing. A more specific example of a machine-readable storage medium may include an electrical connection based on one or more lines, a portable computer disk, a hard disk, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or flash memory), an optical fiber, a portable compact disk read-only memory (CD-ROM), an optical storage device, a magnetic storage device, or any suitable combination of the foregoing.

[0124] To provide interaction with a user, the systems and techniques described herein can be implemented on a computer having: a display device (e.g., a CRT (cathode ray tube) or LCD (liquid crystal display) monitor) for displaying information to the user; and a keyboard and pointing device (e.g., a mouse or trackball) through which the user can provide input to the computer. Other types of devices can also be used to provide interaction with the user; for example, the feedback provided to the user can be any form of sensory feedback (e.g., visual feedback, auditory feedback, or tactile feedback); and input from the user can be received in any form (including acoustic input, voice input, or tactile input).

[0125] The systems and techniques described herein may be implemented in a computing system that includes back-end components (e.g., as a data server), or a computing system that includes middleware components (e.g., an application server), or a computing system that includes front-end components (e.g., a user computer with a graphical user interface or a web browser through which a user can interact with implementations of the systems and techniques described herein), or a computing system that includes any combination of such back-end components, middleware components, or front-end components. The components of the system may be interconnected by any form or medium of digital data communication (e.g., a communication network). Examples of communication networks include: a local area network (LAN), a wide area network (WAN), and the Internet.

[0126] A computer system may include a client and a server. The client and the server are generally remote from each other and usually interact through a communication network. The relationship of client and server is generated by computer programs running on respective computers and having a client-server relationship with each other. The server may be a cloud server, a server of a distributed system, or a server combined with a blockchain.

[0127] Those skilled in the art will appreciate that the embodiments described herein are intended to help readers understand the principles of the present invention, and should be understood that the protection scope of the present invention is not limited to such specific statements and embodiments. Those skilled in the art can make various other specific variations and combinations that do not deviate from the essence of the present invention based on the technical revelations disclosed by the present invention, and these variations and combinations are still within the protection scope of the present invention.

Claims

1. A method for calculating the amount of bird cuts caused by high-speed impact of a bird body based on optical image analysis, characterized in that: There are two situations: the ideal situation where the birdshot attitude is perpendicular to the fixture without deflection and the situation where the birdshot rolls and yaws during flight: In the ideal case where the birdshot attitude is perpendicular to the fixture without deflection, the method includes the following steps: S101. Obtain two frames of images before the birdshot hits the fixture, and mark the feature points of the two frames of images respectively to obtain the marked points and the two frames of images after marking; S102. Connect and extend the same marked points in the two marked frames to obtain the speed direction line of the birdshot flight; S103. Calculate the bird cutting point based on the marked image and pixel ratio relationship; S104. Draw a perpendicular line to the velocity direction line at the marked point, and translate the perpendicular line along the velocity line to intersect the bird-cutting point, record the intersection of the perpendicular line and the velocity direction line as the position of the marked point at the time of impact, and thereby obtain the spatial position of the birdshot at the time of bird impact; S105. Based on the speed direction line of the birdshot flight, the bird cutting point and the spatial position of the birdshot when the bird hits, the bird cutting amount is calculated, and the bird cutting amount calculation of the high-speed impact of the bird body is completed; When the birdshot has a rolling and yaw attitude during flight, the method comprises the following steps: S201. Obtain two frames of images before the birdshot hits the fixture, and mark the feature points of the two frames of images respectively to obtain the marked points, the two frames of images after marking, and the outline of the birdshot in the second frame of image; S202. Select the same marked points in the two marked frames to connect and extend them to obtain the speed direction line of the birdshot flight; S203. Calculate the bird cutting point based on the marked image and pixel ratio relationship; S204. The birdshot outline in the second frame image is proportionally shifted along the velocity direction line until the leading edge of the birdshot hits the bird cutting point. At this time, the birdshot is divided into two parts by the velocity direction line, and the bird cutting amount is calculated based on the proportional relationship between the birdshot and the part of the birdshot divided by the velocity direction line.

2. The method for calculating the amount of bird cuts caused by high-speed impact of a bird body based on optical image analysis according to claim 1 is characterized in that: The step S101 specifically includes the following steps: Using high-speed cameras to monitor the birdshot impact process; The two frames of images before the birdshot hits the fixture are captured from the high-speed camera, and are projected on a plane, and the outline of the birdshot in the two frames of images is drawn by pasting grid lines; The birdshot contours are marked with feature points on the grid lines.

3. The method for calculating the amount of bird cuts caused by high-speed impact of a bird body based on optical image analysis according to claim 1, characterized in that: The second frame of the two frames of images before the birdshot hits the fixture in step S201 is an image just before the birdshot hits the fixture. The birdshot has a constant posture from the frame before the impact until the moment of impact with the fixture, and the roll and yaw of the birdshot are based on the center point as the origin. The step S201 specifically includes the following steps: Using high-speed cameras to monitor the birdshot impact process; The first two frames of images of the birdshot hitting the fixture are captured from the high-speed camera, and the images are projected on a plane, and the outline of the birdshot in the second frame is drawn by pasting grid lines; Mark feature points on the grid lines.

4. The method for calculating the amount of bird cuts caused by high-speed impact of a bird body based on optical image analysis according to claim 1, characterized in that: The marking point in step S202 is a marking point close to the exact center of the birdshot. At this time, the birdshot in the two frames has different global spatial states. Due to the roll and yaw of the birdshot in the second frame, the projection of the birdshot is smaller than the original birdshot outline.

5. The method for calculating the amount of bird cuts caused by high-speed impact of a bird body based on optical image analysis according to claim 1, characterized in that: The step S103 and the step S203 specifically include the following sub-steps: A scale is pasted on the side boundary line of the fixture, and a high-speed camera is used to monitor the birdshot impact process to obtain the bird strike point; The height of the bird strike point from the upper edge of the typical blade part is measured by a ruler ; Measure the height from the upper edge of the typical blade to the top of the fixture using a scale ; Based on the height of the bird strike point from the upper edge of the typical blade part , Height from the upper edge of the typical blade to the top of the fixture The bird-cutting point is calculated based on the pixel ratio relationship in the same frame image.

6. The method for calculating the amount of bird cuts caused by high-speed impact of a bird body based on optical image analysis according to claim 5, characterized in that: The height of the bird strike point from the upper edge of the typical blade part , Height from the upper edge of the typical blade to the top of the fixture The bird-cutting point is calculated based on the pixel ratio relationship in the same frame image, which specifically includes the following steps: According to the height of the bird strike point from the upper edge of the typical blade and the height from the upper edge of the typical blade to the top of the fixture , calculate the actual distance between the bird impact point and the upper edge of the fixture, and the calculation formula is: in, Indicates the actual distance between the bird impact point and the upper edge of the fixture; According to the pixel ratio in the same frame image, the actual distance from the upper edge of the fixture to the root of the fixture is , the distance between pixels in the photo is , then the proportional conversion relationship of the fixture boundary line is for: ； According to the same conversion ratio on the same boundary line, the pixel distance between the impact point on the fixture boundary line and the upper edge of the fixture is The expression formula is: According to the pixel distance between the impact point and the upper edge of the fixture on the fixture boundary line You can get the bird cutting point.

7. The method for calculating the amount of bird cuts caused by high-speed impact of a bird body based on optical image analysis according to claim 1, characterized in that: The step S105 specifically includes the following steps: Draw the birdshot outline along the pasted grid line at the center of the birdshot spatial position in the image when the bird hits. The pixel length of the birdshot outline is , the birdshot outer contour is divided into and Two parts; Place the birdshot outside the outline The part starts from the intersection of the birdshot outer contour line and the velocity direction line, and moves along the velocity direction line to the spatial position of the birdshot when the bird hits the velocity direction line while maintaining the segmentation ratio. Then the birdshot outer contour line is segmented again by the bird-cutting point, and the measurement is performed. The length of the part of the segment divided by the cut point ; Based on the pixel length of the birdshot outer contour and The length of the part of the segment divided by the cut point , you can get the amount of bird cut , and its calculation formula is: ； Repeat the above steps, take at least three birdshot outer contour lines on the entire birdshot to calculate the bird cut amount, and take the average to obtain the final bird cut amount, which is calculated as follows: in, It indicates the amount of bird cut when the birdshot attitude is perpendicular to the ideal condition with no deflection of the fixture. , and Represents the first, second and The amount of bird cut calculated by this calculation is Indicates the total number of selected contours.

8. The method for calculating the amount of bird cuts caused by high-speed impact of a bird body based on optical image analysis according to claim 1, characterized in that: The calculation formula of the bird cutting amount in step S204 is: in, It indicates the amount of bird cut when the birdshot has a rolling and yaw attitude during flight. It means birdshot. Birdshot The part divided by the velocity direction line.

9. A bird body high-speed impact bird cutting amount calculation system based on optical image analysis, characterized in that: It comprises a processor, and the processor is used to execute the method for calculating the amount of bird cut by high-speed impact of a bird body based on optical image analysis as described in any one of claims 1-8.

10. A computer-readable storage medium, characterized in that: The storage medium stores computer instructions. In response to the computer reading the computer instructions in the storage medium, the computer executes the method for calculating the amount of bird cuts by high-speed impact of a bird body based on optical image analysis as described in any one of claims 1 to 8.

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