High-precision target positioning monitoring system suitable for high-dynamic wind tunnel test environment

Abstract

The invention belongs to the field of high-precision monitoring and positioning of wind tunnel test pieces, and relates to a high-precision target positioning and monitoring system suitable for a high-dynamic wind tunnel test environment. Through a special installation and deployment mode designed for a wind tunnel site mode, a target capture principle based on infrared reflection, a target capturable positioning tool scheme suitable for a complex surface, and a real-time positioning data transmission algorithm, positioning of a key part of a dynamic test piece in a wind tunnel test is realized. The method has the advantages of high-precision and high-frame-rate positioning of the target at a high wind speed, intuition and visibility, difficulty in losing target positioning, low delay and high-efficiency transmission, forms a full-scene positioning and transmission debugging software and hardware system for the target in the tunnel, and can greatly improve the positioning precision of the related target and the utilization efficiency of positioning data in a high-dynamic wind tunnel test verification environment.

Description

Technical Field

[0001] This application belongs to the field of high-precision monitoring and positioning of wind tunnel test components, and specifically relates to a high-precision target positioning and monitoring system suitable for high-dynamic wind tunnel test environments. Background Technology

[0002] In wind tunnel testing, real-time monitoring of key components of the test specimen allows for observation of the current test results and provides a reference for system operation. The accuracy and anti-interference capability of this positioning affect the operation of other systems that rely on the positioning data. The main challenges in positioning wind tunnel test specimens are the complex wind tunnel environment, the vibration of components due to airflow interference at high wind speeds, the unconventional shape of the test specimen model making direct positioning difficult, and the variable size and position of the specimen with a large operating area. This invention overcomes the influence of high-speed airflow on camera positioning through a special camera installation and connection method. It achieves high-precision positioning across the entire field by designing and arranging cameras specifically for the wind tunnel environment and utilizing the infrared camera-reflective sphere positioning principle. Furthermore, it establishes a hardware and software system and method for full-scene target positioning, transmission, and debugging within the wind tunnel, significantly improving the accuracy of target positioning and the efficiency of positioning data utilization in high-dynamic wind tunnel testing environments. Summary of the Invention

[0003] To address the aforementioned problems, this application provides a high-precision target positioning and monitoring system suitable for high-dynamic wind tunnel testing environments, comprising:

[0004] Includes both hardware and software components;

[0005] The hardware includes multiple infrared cameras, a switch, and a positioning monitoring terminal. The infrared cameras are connected to the switch via network cables, and the switch is connected to the positioning monitoring terminal via network cables. The infrared cameras are fixed to the wind tunnel wall via a connecting device, which includes a fixing disk and an angle adjustment device, enabling the camera to be adjusted 180° in both horizontal and vertical directions. The infrared cameras are configured to emit active infrared light and capture the reflected light from reflective spheres arranged on the surface of the test specimen.

[0006] The software component includes a positioning monitoring interface, a positioning information transmission code, and a positioning information storage file. The positioning monitoring interface is used to visually display the target positioning screen, the positioning information transmission code is used to transmit positioning information to other systems in real time, and the positioning information storage file is used to save positioning data for subsequent analysis and processing.

[0007] Preferably, the infrared cameras are arranged as follows:

[0008] Obtain the detection area of ​​each infrared camera, wherein the detection area is a cone, and establish the cone model;

[0009] Establish the minimum sphere to cover the active area of ​​the test specimen;

[0010] Establish a wind tunnel wall model, and place the smallest sphere inside the wind tunnel wall model according to the experimental requirements;

[0011] Set constraints to ensure that all cone models encompass the smallest sphere;

[0012] Obtain the overlapping area between the vertex of each cone and the wind tunnel wall. The overlapping area is the optimal installation area for the infrared camera corresponding to the cone.

[0013] All infrared cameras are installed in the optimal installation area to obtain the infrared camera layout scheme.

[0014] Preferably, the surface of the test piece is arranged with no less than four reflective spheres, which together form a rigid body marker; the positioning information of the rigid body marker includes the position, angle and quaternion of the x, y and z axes.

[0015] Preferably, the test specimen can be captured simultaneously by at least three infrared cameras.

[0016] Preferably, the smallest sphere includes the smallest region that covers the active area of ​​the reflective sphere.

[0017] Preferably, after determining the optimal installation area for the infrared camera,

[0018] Also includes:

[0019] The first step is to identify the surface area on each test piece where reflective balls can be installed, as well as the area where reflective balls move due to the movement of the test piece. Based on the basic principle that any reflective ball needs to be captured by at least 3 infrared cameras, the monitoring targets of each infrared camera are reasonably allocated.

[0020] The second step is to use the monitoring area of ​​any infrared camera as a guide, consider the initial installation position of the camera as the farthest end of the wind tunnel working area of ​​the optimal installation area, and use infrared rangefinders and other ray instruments to adjust the camera angle so that the center ray of the camera's field of view is aligned with the surface of the reflective ball installed at the initial position of the test piece.

[0021] Finally, the camera angle or position is fine-tuned according to the moving area of ​​the test piece, the moving range of each test piece and the mutual occlusion situation are analyzed, and the camera height or camera angle is adjusted according to the moving direction of the test piece so that the center of the camera field of view points to the middle of the moving area of ​​the test piece, ensuring that any area where the reflective ball is arranged can be captured during the operation phase.

[0022] Preferably, the positioning data transmission uses the TCP protocol; first, the rigid body positioning information is read in real time, the data is processed according to the requirements of other systems, and then the required data is transmitted through the TCP protocol.

[0023] Preferably, the angle adjustment device enables the camera to directly withstand the effects of high wind speeds and maintain stable positioning.

[0024] Preferably, the positioning and monitoring interface displays the 2D reflective point position, the 3D reconstructed reflective sphere position, and rigid body positioning information of each infrared camera in real time.

[0025] 1) A hardware and software system for real-time positioning and monitoring of test specimens in a high-dynamic wind tunnel is proposed.

[0026] 2) By employing a special camera installation and connection method, the influence of high-speed airflow on camera positioning was overcome. A camera layout scheme tailored to the wind tunnel environment and the infrared camera-reflective sphere positioning principle were used to achieve high-precision positioning across the entire field. This resulted in a method for full-scene positioning, transmission, and debugging of test specimens within the wind tunnel.

[0027] 3) It has the advantages of high-precision and high-frame-rate target positioning under high wind speed, intuitive visualization and easy target positioning, and efficient transmission. Attached Figure Description

[0028] Figure 1 This is a diagram of the wind tunnel test component target positioning and monitoring system architecture.

[0029] Figure 2 This is a flowchart of the target positioning and monitoring method for test specimens.

[0030] Figure 3 This is a schematic diagram of the infrared camera setup for positioning wind tunnel test specimens.

[0031] Figure 4 This is a structural diagram of the camera connection components.

[0032] Figure 5 This is a flowchart of the location information transmission algorithm. Detailed Implementation

[0033] To make the purpose, technical solution and advantages of this application clearer, the technical solution of the implementation of this application will be described in more detail below with reference to the accompanying drawings. In the drawings, the same or similar reference numerals represent the same or similar elements or elements with the same or similar functions throughout. The described implementation is a part of the implementation of this application, but not all of the implementation. The implementation described below with reference to the accompanying drawings is exemplary and intended to explain this application, and should not be construed as a limitation of this application. All other implementations obtained by those skilled in the art based on the implementation of this application without creative effort are within the scope of protection of this application. The implementation of this application will be described in detail below with reference to the accompanying drawings. (1) The overall architecture of the test piece target positioning monitoring system is as follows Figure 1As shown, the system consists of both hardware and software components. The hardware includes an infrared camera, a switch, and a positioning monitoring terminal. The infrared camera is connected to the switch, and the switch is connected to the positioning monitoring terminal via network cables. The infrared camera is mounted on the wind tunnel wall using a designed connection device, and reflective spheres are placed on the surface of the test specimen. The software includes a positioning monitoring interface, positioning information transmission codes, and positioning information storage files. The positioning monitoring interface visually displays the target's positioning, the positioning information transmission codes transmit relevant positioning information to other systems in real time, and the positioning information storage files store the positioning data for subsequent analysis and processing.

[0034] (2) Flowchart of the test specimen target positioning and monitoring method is as follows Figure 2 This method is based on the content mentioned in (1). The steps of this method are as follows: First, design the infrared camera layout scheme according to the current test piece area to ensure that the combined field of view of the infrared cameras can completely cover the active area of ​​the test piece. Then, install and connect the various hardware components of the system. After the connection is completed, the positioning system software interface can be opened to observe the positioning status of the test piece in real time. Finally, the positioning data of the test piece is transmitted to other systems through the positioning data transmission code, or the data is recorded for post-processing analysis of the positioning data and the test status of the test piece. The specific implementation details of the method are described in detail in (3)-(6).

[0035] (3) Figure 3 This is a schematic diagram of the infrared camera setup for positioning wind tunnel test specimens. The working area of ​​a conventional wind tunnel can be simplified. Figure 3 As shown in the diagram, the dark blue rectangles, gray areas, and red areas represent different parts of the test specimen model. For the positioning of the test specimen within the wind tunnel, it is necessary to consider achieving positioning throughout its entire operating area. Therefore, the camera installation positions are designed according to the black pyramidal markings in the diagram. The blue fan-shaped areas represent the areas detectable by a single camera, and the overlapping blue areas represent the common areas detectable by multiple cameras. The overlapping blue areas covering all test specimen positions indicate that the test specimen can be captured and positioned by multiple infrared cameras.

[0036] (4) The camera installation design is specifically divided into the following steps.

[0037] First, obtain the optimal installation area and the detection area of ​​each infrared camera, which is a cone. Establish the cone model. Then, establish the minimum sphere covering the active area of ​​the test specimen. Next, establish a wind tunnel wall model and place the minimum sphere inside the wind tunnel wall model according to experimental requirements. Set constraints for all cone models to cover the minimum sphere. Obtain the overlapping area between the vertices of each cone and the wind tunnel wall; this overlapping area is the optimal installation area for the corresponding infrared camera. Finally, install all infrared cameras in the optimal installation area.

[0038] After obtaining the optimal installation area, the monitoring targets of each infrared camera are then assigned according to the location of the test specimen.

[0039] The surface area on which reflective balls can be installed on each test piece and the area where reflective balls move due to the movement of the test piece are clearly defined. Based on the basic principle that any reflective ball needs to be captured by at least 3 infrared cameras, the monitoring targets of each infrared camera are reasonably allocated.

[0040] Infrared cameras are initially installed according to the monitoring targets. For any given infrared camera, the monitoring area of ​​that camera is used as a guide, and the initial installation position of the camera is considered to be at the farthest end of the wind tunnel working area. Infrared rangefinders and other X-ray instruments are used to assist in adjusting the camera angle so that the center ray of the camera's field of view is aligned with the surface of the reflective sphere installed at the initial position of the test specimen. At this point, the camera's test range is relatively large, and all test specimens can be captured by the infrared camera.

[0041] Finally, the camera angle or position is fine-tuned based on the moving area of ​​the test specimen. By analyzing the moving range of each test specimen and the mutual occlusion, the camera height or camera angle is adjusted according to the moving direction of the test specimen. This ensures that the center of the camera's field of view is pointed in the middle of the moving area of ​​the test specimen, guaranteeing that any area where the reflective spheres are arranged can be captured during the operation phase.

[0042] (5) System Hardware Connection: First, use network cables to connect the infrared camera to the switch, and the switch to the positioning and monitoring terminal. The camera connection structure is a connection device designed for wind tunnel testing sites, connecting the infrared camera to the wind tunnel wall. Its main structure is as follows: Figure 4 The connecting device consists of a fixed disc and an angle adjustment mechanism, allowing the camera to be adjusted 180° horizontally and vertically without being affected by high wind speeds. Reflective balls are installed on the surface of the test specimen, using screw holes to install them in the target positioning area. At least four reflective balls are used to mark the positioning area on the test specimen and are captured by the infrared camera, forming an identifiable marker for that positioning area.

[0043] (6) The positioning monitoring software interface displays the current positioning status and information of the test piece in real time. The positioning principle is that the infrared camera LED emits active infrared light, which illuminates the reflective sphere and is reflected back to the camera. The positioning monitoring software reconstructs the 3D position of the reflective sphere based on the 2D reflection points inside the camera and triangulation, thereby achieving the positioning of the test piece. The positioning monitoring interface displays the 2D reflection point position of each camera and the 3D position of the reflective sphere obtained from the 3D reconstruction, and displays the positioning information. The positioning information includes the x, y, and z-axis positions and angles of the rigid body composed of no less than four reflective spheres, as well as the rigid body quaternions.

[0044] (7) Positioning data can be simultaneously sent to other systems and stored. The positioning data of the test specimen is transmitted to other systems using the positioning information transmission code. The specific process is as follows: Figure 5As shown. First, the target rigid body positioning information described in (5) is read in real time. The positioning data is processed according to the data requirements of other systems. Then, the required data is transmitted using the TCP protocol.

[0045] The above description is merely a specific embodiment of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

Claims

1. A high-precision target positioning and monitoring system suitable for high-dynamic wind tunnel testing environments, characterized in that, include: Includes both hardware and software components; The hardware includes multiple infrared cameras, a switch, and a positioning monitoring terminal. The infrared cameras are connected to the switch via network cables, and the switch is connected to the positioning monitoring terminal via network cables. The infrared cameras are fixed to the wind tunnel wall via a connecting device, which includes a fixing disk and an angle adjustment device, enabling the camera to be adjusted 180° in both horizontal and vertical directions. The infrared cameras are configured to emit active infrared light and capture the reflected light from reflective spheres arranged on the surface of the test specimen. The software component includes a positioning monitoring interface, a positioning information transmission code, and a positioning information storage file. The positioning monitoring interface is used to visually display the target positioning screen, the positioning information transmission code is used to transmit positioning information to other systems in real time, and the positioning information storage file is used to save positioning data for subsequent analysis and processing.

2. The high-precision target positioning and monitoring system suitable for high-dynamic wind tunnel test environments as described in claim 1, characterized in that, The infrared cameras are arranged as follows: Obtain the detection area of ​​each infrared camera, wherein the detection area is a cone, and establish the cone model; Establish the minimum sphere to cover the active area of ​​the test specimen; Establish a wind tunnel wall model, and place the smallest sphere inside the wind tunnel wall model according to the experimental requirements; Set constraints to ensure that all cone models encompass the smallest sphere; Obtain the overlapping area between the vertex of each cone and the wind tunnel wall. The overlapping area is the optimal installation area for the infrared camera corresponding to the cone. Install all infrared cameras in the optimal installation area.

3. The high-precision target positioning and monitoring system suitable for high-dynamic wind tunnel test environments as described in claim 2, characterized in that, The surface of the test piece is arranged with no fewer than four reflective spheres, which together form a rigid body marker; the positioning information of the rigid body marker includes the position, angle and quaternion of the x, y and z axes.

4. The high-precision target positioning and monitoring system suitable for high-dynamic wind tunnel test environments as described in claim 3, characterized in that, The test specimen can be captured simultaneously by at least three infrared cameras.

5. The high-precision target positioning and monitoring system suitable for high-dynamic wind tunnel test environments as described in claim 3, characterized in that, The smallest sphere includes the smallest region that covers the active area of ​​the reflective sphere.

6. The high-precision target positioning and monitoring system suitable for high-dynamic wind tunnel test environments as described in claim 3, characterized in that, After determining the optimal installation area for the infrared camera, Also includes: The first step is to identify the surface area on each test piece where reflective balls can be installed, as well as the area where reflective balls move due to the movement of the test piece. Based on the basic principle that any reflective ball needs to be captured by at least 3 infrared cameras, the monitoring targets of each infrared camera are reasonably allocated. The second step is to use the monitoring area of ​​any infrared camera as a guide, consider the initial installation position of the camera as the farthest end of the wind tunnel working area of ​​the optimal installation area, and use infrared rangefinders and other ray instruments to adjust the camera angle so that the center ray of the camera's field of view is aligned with the surface of the reflective ball installed at the initial position of the test piece. Finally, the camera angle or position is fine-tuned according to the moving area of ​​the test piece, the moving range of each test piece and the mutual occlusion situation are analyzed, and the camera height or camera angle is adjusted according to the moving direction of the test piece so that the center of the camera field of view points to the middle of the moving area of ​​the test piece, ensuring that any area where the reflective ball is arranged can be captured during the operation phase.

7. The high-precision target positioning and monitoring system suitable for high-dynamic wind tunnel test environments as described in claim 1, characterized in that, The positioning data transmission uses the TCP protocol; first, the rigid body positioning information is read in real time, the data is processed according to the requirements of other systems, and then the required data is transmitted through the TCP protocol.

8. The high-precision target positioning and monitoring system suitable for high-dynamic wind tunnel test environments as described in claim 1, characterized in that, The angle adjustment device enables the camera to directly withstand the effects of high wind speeds and maintain stable positioning.

9. The high-precision target positioning and monitoring system suitable for high-dynamic wind tunnel test environments as described in claim 1, characterized in that, The positioning and monitoring interface displays the 2D reflective point position, the 3D reconstructed reflective sphere position, and rigid body positioning information of each infrared camera in real time.

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