Thermal imaging aerial photography device
By employing two thermal imaging cameras in the thermal imaging aerial photography device, with low field-of-view overlap, appropriate lens normal angle, and infrared thermal imaging, the efficiency and accuracy problems of large-area monitoring in existing technologies are solved, and rapid and efficient thermal imaging aerial photography is achieved.
Patent Information
- Application Number
- CN202520381048.5
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-03-06
- Publication Date
- 2026-01-20
- Estimated Expiration
- 2035-03-06
AI Technical Summary
Existing thermal imaging aerial photography equipment suffers from low pixel values and narrow field of view when monitoring large areas, making it difficult to meet the needs of efficient monitoring. This is especially true in areas such as monitoring cooling water temperature in nuclear power plants, monitoring burned area in forest fires, and monitoring wildlife populations, where time is tight and the scope is wide, and existing equipment is unable to complete the tasks quickly and accurately.
Design a thermal imaging aerial photography device that uses two thermal imaging cameras with the lenses mounted downwards. The overlap rate of the field of view is less than 10%, the lens normal angle is 30° to 40°, and the infrared light with a wavelength of 10μm is used for thermal imaging. The field of view is 20° to 50°, and the composite resolution is 2200×1024. It is suitable for UAVs or manned aircraft.
It achieves efficient and rapid large-area thermal imaging aerial photography, which can acquire thermal imaging data over a larger area in a short time, improving the accuracy and efficiency of monitoring, reducing the endurance requirements of UAVs, and reducing the risk of equipment damage.
Smart Images
Figure CN223812711U_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The present application relates to an aerial photography thermal imaging remote sensing device, in particular to a thermal imaging aerial photography device, and more particularly to an array type thermal imaging aerial photography device with a wide viewing angle. BACKGROUND
[0002] In many fields such as security monitoring, forest fire prevention, power inspection and industrial detection, obtaining thermal imaging data by using unmanned aerial vehicles has become an efficient and necessary means.
[0003] In the prior art, there are devices that use visible light imaging to perform the above monitoring. Although the visible light imaging device has high resolution, its field of view is very narrow, and it is more suitable for monitoring small areas such as urban buildings, roads, and parks, but it is completely unable to monitor large areas such as thousands of square kilometers of sea areas, forest fires, and wildlife habitats.
[0004] In many fields such as security monitoring, forest fire prevention, power inspection and industrial detection, obtaining thermal imaging data by using unmanned aerial vehicles has become an efficient and necessary means. Unmanned aerial vehicles can quickly reach target areas and accurately collect thermal imaging data, providing strong support for various monitoring work.
[0005] In the prior art, there are devices that use visible light imaging to perform the above monitoring. Although the visible light imaging device has high resolution, its field of view is very narrow, and it is more suitable for monitoring small areas such as urban buildings, roads, and parks, but it is completely unable to monitor large areas such as thousands of square kilometers of sea areas, forest fires, and wildlife habitats.
[0006] In the monitoring of the cooling water temperature of a nuclear power plant, since the cooling water of the nuclear power plant mainly enters the cooling device of the nuclear power plant during high tide and is discharged from the nuclear power plant, and the high tide time is only about 1 hour, it is necessary to comprehensively monitor the water temperature of the sea area where the cooling water of the nuclear power plant is discharged within about 1 hour. In addition, in the monitoring of the fire area of a forest fire, since the fire situation is urgent and the fire spreads quickly, it is necessary to completely grasp the fire area data within a very short period of time. In addition, in the monitoring of wild animals such as Tibetan antelope populations, since the Tibetan antelope moves very fast, if the monitoring of the entire population is not completed quickly, the movement of the population will inevitably lead to inaccurate monitoring results.
[0007] Therefore, there is a need for a thermal imaging aerial photography device that can efficiently and quickly complete aerial photography of large areas.
[0008] In many fields, unmanned aerial vehicle thermal imaging data collection plays a key role. For example, in the monitoring of the temperature of the warm water discharged from a nuclear power plant, the water body is significantly affected by the tide, and work needs to be carried out during the spring tide period and the neap tide period, and monitoring needs to be carried out at high tide and low tide during each tide period. Due to the short time of the tide period and the large monitoring range, it is necessary to rely on multiple unmanned aerial vehicles to take off at the same time for thermal imaging aerial photography.
[0009] Forest fire monitoring also faces challenges. The fire is urgent and the fire spreads rapidly, and it is necessary to accurately grasp the data of the burned area in a very short time in order to timely develop response strategies.
[0010] Wildlife population monitoring also has difficulties, such as Tibetan antelopes, which move at extremely high speeds. If the entire population cannot be monitored quickly, the accuracy of the monitoring results will be difficult to guarantee once the population moves.
[0011] In summary, whether it is the monitoring of water bodies affected by tides, the monitoring of forest fires in a race against time, or the monitoring of fast-moving populations, there is an urgent need for a thermal imaging aerial photography device that can efficiently and quickly complete large-area thermal imaging aerial photography to meet complex and strict monitoring needs in different scenarios.
[0012] The technical problem to be solved by the utility model
[0013] Based on the above situation of the prior art, the technical problem to be solved by the utility model is to provide a thermal imaging aerial photography device that can efficiently and quickly complete large-area thermal imaging aerial photography.
[0014] Another technical problem to be solved by the utility model is to provide a thermal imaging aerial photography device that can realize high-resolution thermal imaging aerial photography. Utility model content
[0015] To solve the above technical problems, the utility model provides the following technical solutions.
[0016] Scheme 1. A thermal imaging aerial photography device has a flight device and two thermal imaging cameras, the lenses of the thermal imaging cameras are installed downward below the flight device, characterized in that the overlap rate of the field of view range of the two thermal imaging cameras is 10% or less.
[0017] Scheme 2. The thermal imaging aerial photography device of the above scheme 1, characterized in that the overlap rate of the field of view range of the two thermal imaging cameras is 5% or less.
[0018] Scheme 3. The thermal imaging aerial photography device of the above scheme 1, characterized in that the included angle between the respective lens normals of the two thermal imaging cameras is 30°-40°.
[0019] Scheme 4. The thermal imaging aerial photography device of scheme 1, wherein the angle between the lens normal of each of the two thermal imaging cameras is 36°.
[0020] Scheme 5. The thermal imaging aerial photography device of scheme 1, wherein the boundary of the field of view of each of the two thermal imaging cameras is in contact with each other but the field of view of each of the two thermal imaging cameras does not overlap.
[0021] Scheme 6. The thermal imaging aerial photography device of scheme 1, wherein the two thermal imaging cameras perform thermal imaging aerial photography by using infrared rays with a wavelength of 10 μm.
[0022] Scheme 7. The thermal imaging aerial photography device of scheme 1, wherein the field of view angle of the thermal imaging camera is 20°-50° (H) and 15°-40° (V).
[0023] Scheme 8. The thermal imaging aerial photography device of scheme 1, wherein the field of view angle of the thermal imaging camera is 46.4° (H) and 37° (V).
[0024] Scheme 9. The thermal imaging aerial photography device of scheme 1, wherein the combined resolution of the two thermal imaging cameras is 2200x1024.
[0025] Scheme 10. The thermal imaging aerial photography device of scheme 1, wherein the flight device is a drone or manned aircraft.
[0026] Technical effects of the utility model
[0027] The thermal imaging aerial photography device of the utility model has a flight device and two thermal imaging cameras, the lens of the thermal imaging camera is installed downward below the flight device, and the feature is that the overlap rate of the field of view of the two thermal imaging cameras is below 10%. As described above, in the utility model, two thermal imaging cameras are arranged below the thermal imaging aerial photography device, and the overlap rate of the field of view of the two thermal imaging cameras is below 10%, thereby forming a wider field of view angle, obtaining larger range of thermal imaging data, and enabling the thermal imaging camera to realize very large effective view angle, thereby being capable of efficiently and quickly completing thermal imaging aerial photography of a large area. BRIEF DESCRIPTION OF DRAWINGS
[0028] Figure 1 is a schematic view of two thermal imaging cameras of the thermal imaging device and the field of view thereof;
[0029] Figure 2 is a schematic view of the symmetry axis and the lens normal of the two thermal imaging cameras of the thermal imaging device;
[0030] Fig. 3(a), Fig. 3(b), Fig. 3(c) are schematic diagrams of a method for calculating the field of view overlap rate of two thermal imaging cameras of the thermal imaging device according to the present application;
[0031] Symbol explanation
[0032] 11, 12: thermal imaging cameras
[0033] 21, 22: field of view range of the thermal imaging cameras
[0034] 30: symmetry axis of the two thermal imaging cameras
[0035] 31, 32: lens normal of the thermal imaging cameras
[0036] 40: an arbitrary plane perpendicular to the lens normal
[0037] S21, S22: field of view area on the plane 40
[0038] S50: overlap area of the field of view DETAILED DESCRIPTION
[0039] The thermal imaging aerial photography device according to the present application comprises a flight device and two thermal imaging cameras, the lenses of the thermal imaging cameras are installed downward below the flight device, characterized in that the overlap rate of the field of view ranges of the two thermal imaging cameras is less than or equal to 10%.
[0040] Figure 1 Fig. 1 is a schematic diagram of two thermal imaging cameras and their fields of view according to the present application. The two thermal imaging cameras are camera 11 on the left and camera 12 on the right. The two cameras are installed in a lens-down manner below a flight device (not shown). The two cameras respectively generate corresponding field of view ranges below the lenses, as shown in Fig. 1. The field of view range of camera 11 is approximately the range of shadow 21, and the field of view range of camera 12 is approximately the range of shadow 22. The overlap rate of shadow 21 and shadow 22 is less than or equal to 10%. Figure 1
[0041] When the overlap rate of the field of view range of camera 11 and the field of view range of camera 12 is less than or equal to 10%, the effective field of view range of the thermal imaging aerial photography device can be greatly improved, so that the thermal imaging aerial photography of a large area can be efficiently and quickly completed.
[0042] It should be noted that in the past, when aerial photography is carried out by using visible light cameras and two cameras continue to shoot, in order to ensure the resolution of the cameras, the overlap rate of the field of view range of the two cameras is required to be more than 30%. Once the overlap rate is less than 30%, the resolution of the shooting cannot be ensured, and the photographed photos or videos cannot be used as a monitoring basis. For example, in the process of shooting the wild habitat of Tibetan antelopes to count the population of Tibetan antelopes, if visible light double cameras are used for shooting, if the overlap rate of the field of view range of the cameras is less than 30%, the recognition accuracy of the Tibetan antelopes cannot even reach 60% below the resolution of 5 cm, and such data cannot be used as a monitoring basis.
[0043] However, the designer of the utility model surprisingly found that when aerial photography is carried out by using thermal imaging cameras, even if the overlap rate of the field of view range is very low, the monitoring object can still be accurately recognized, and accordingly, the designer of the utility model proposed a new technical scheme, that is, when aerial photography is carried out by using thermal imaging cameras, the overlap rate of the field of view of the two cameras is reduced, thereby greatly increasing the effective field of view range of the aerial photography device, so that the shooting area can be increased each time, which greatly shortens the completion time of the large-area aerial photography task.
[0044] In this way, even the unmanned aerial vehicle with a short cruising range can complete the large-area aerial photography task, which greatly reduces the requirements for the unmanned aerial vehicle.
[0045] In addition, the overlap rate of the field of view of the two cameras (11, 12) can be lower, preferably 8% or lower, more preferably 5% or lower, and particularly preferably 3% or lower. For the aerial photography task of measuring the area of forest fires, the thermal imaging aerial photography device of the present application with a lower overlap rate of the field of view can be used, which can further expand the shooting area and further reduce the residence time of the thermal imaging aerial photography device in the fire field. This not only allows the fire department to quickly grasp the relevant data of the fire field, but also reduces the damage of the high temperature of the fire field to the thermal imaging aerial photography device.
[0046] In addition, it should be noted that the designer of the utility model has noticed that in the aerial photography device of the utility model, the overlap rate of the field of view of the two cameras (11, 12) should not be higher than 10%. When the overlap rate of the field of view is higher than 10%, the loss of the effective field of view is large, which is not conducive to realizing fast and efficient aerial photography.
[0047] Furthermore, the boundaries of the field of view ranges of the two thermal imaging cameras are attached to each other but the field of view ranges of the two thermal imaging cameras do not overlap (i.e. the overlap rate of the field of view is 0%). That is, as shown in FIG. 1, the field of view range of the first thermal imaging camera 11 is a rectangle, and the field of view range of the second thermal imaging camera 12 is a rectangle which is attached to the field of view range of the first thermal imaging camera 11 but does not overlap with the field of view range of the first thermal imaging camera 11. Figure 1As shown, the right side boundary of the field of view range 21 of the camera 11 and the left side boundary of the field of view range 22 of the camera 12 are in contact with each other, and the field of view ranges of the two cameras are in contact with each other but there is no overlapping part. In this way, the visual angle range of the thermal imaging aerial photography device is maximized, and a large area aerial photography task can be completed at a very fast speed. Especially for the determination of the cooling water discharge temperature of a nuclear power plant, which is a task with a very large area, the use of two thermal imaging cameras with field of view ranges in contact with each other but no overlapping can quickly complete the task, especially in the case of a large sea area and poor sea conditions, the extremely high shooting efficiency not only can quickly obtain the sea water temperature related information, but also can protect the safety of the aerial photography device including the unmanned aerial vehicle.
[0048] The overlap rate is defined and calculated as follows. As shown in FIG. 2, the two cameras (11, 12) are involved in an axial symmetric mode. The symmetry axis 30 is located between the two cameras (11, 12). As shown in FIG. 3(a), on any plane 40 perpendicular to the symmetry axis 30, the area of the overlapping region S50 of the field of view of the two cameras (i.e. the polygon S50 in FIG. 3(a)) is divided by the area of the field of view range of the camera with the smallest field of view range on the plane 40, and the percentage obtained is the overlap rate. For example, as shown in FIG. 3(b), on the plane 40, the field of view area of the camera 12 is S22, as shown in FIG. 3(b), on the plane 40, the field of view area of the camera 11 is S21, and S21 < S22, then the area of the polygon S50 is divided by the area of S21, and the percentage obtained is the overlap rate. Figure 2 As shown in FIG. 4, the two cameras (11, 12) are involved in an axial symmetric mode. The symmetry axis 30 is located between the two cameras (11, 12). As shown in FIG. 5(a), on any plane 40 perpendicular to the symmetry axis 30, the area of the overlapping region S50 of the field of view of the two cameras (i.e. the polygon S50 in FIG. 5(a)) is divided by the area of the field of view range of the camera with the smallest field of view range on the plane 40, and the percentage obtained is the overlap rate. For example, as shown in FIG. 5(b), on the plane 40, the field of view area of the camera 12 is S22, as shown in FIG. 5(b), on the plane 40, the field of view area of the camera 11 is S21, and S21 < S22, then the area of the polygon S50 is divided by the area of S21, and the percentage obtained is the overlap rate.
[0049] Figure 2 As shown in FIG. 6, the two cameras (11, 12) are involved in an axial symmetric mode. The camera 11 is tilted to the left side with respect to the symmetry axis 30, and the camera 12 is tilted to the right side with respect to the symmetry axis 30. As shown in FIG. 7(a), on any plane 40 perpendicular to the symmetry axis 30, the area of the overlapping region S50 of the field of view of the two cameras (i.e. the polygon S50 in FIG. 7(a)) is divided by the area of the field of view range of the camera with the smallest field of view range on the plane 40, and the percentage obtained is the overlap rate. For example, as shown in FIG. 7(b), on the plane 40, the field of view area of the camera 12 is S22, as shown in FIG. 7(b), on the plane 40, the field of view area of the camera 11 is S21, and S21 < S22, then the area of the polygon S50 is divided by the area of S21, and the percentage obtained is the overlap rate. Figure 2 As shown in FIG. 8, the lens normal line of the camera 11 is the normal line 31, and the lens normal line of the camera 12 is the normal line 32. In order to make the overlap rate of the field of view ranges of the two cameras less than 10%, the included acute angle (hereinafter referred to as the included angle) between the lens normal lines 31 and 32 of the two cameras can be set to be less than or equal to 40°. When the included angle between the lens normal lines 31 and 32 is set to be less than or equal to 40°, the overlap rate of the field of view ranges of the two lenses can be less than or equal to 10%. When the included angle between the lens normal lines 31 and 32 of the two cameras is less than or equal to 40°, the included angles between the lens normal lines (31, 32) of the camera 11 and the camera 12 and the symmetry axis 30 are both less than or equal to 20°.
[0050] In addition, it should be noted that the designer of the utility model has found that the included angle between the lens normal lines (31, 32) of the two cameras (11, 12) in the aerial photography device of the utility model should not be higher than 40°. When the included angle between the lens normal lines (31, 32) of the two cameras (11, 12) is higher than 40°, the field of view overlap of the two cameras will become more, resulting in a large loss of effective field of view, which is not conducive to realizing rapid and efficient aerial photography.
[0051] Preferably, the included angle between the respective lens normal lines 31 and 32 of the two thermal imaging cameras is 36°, that is, the included angle between the lens normal lines (31, 32) of the camera 11 and the camera 12 and the symmetry axis 30 is 18°. At this included angle, the two cameras have a more appropriate field of view overlap rate (about 5%), at which angle, the aerial photography device can have a very large effective field of view, and the field of view of the two cameras can also have a certain overlap, so that there will be no gap between the fields of view of the cameras due to the flight attitude, the state of the flight device or the installation state of the cameras, thereby ensuring that no data is missed.
[0052] In the thermal imaging aerial photography device of the utility model, the two thermal imaging cameras use infrared rays with a wavelength of 10 μm for thermal imaging aerial photography. When using infrared rays for thermal imaging aerial photography, the propagation distance is longer due to the longer wavelength, so the unmanned aerial vehicle can take pictures at a higher rising height, for example, the rising height (picture taking height) can reach 700-800 m away from the picture taking target. Such a picture taking height cannot be achieved by visible light photography. When taking pictures with visible light, the highest picture taking height is 200-300 m, and at a higher picture taking height, the resolution cannot be achieved.
[0053] Since infrared rays are used for taking pictures, the unmanned aerial vehicle of the utility model can take pictures at a very high picture taking height, which can be more than 600 m, preferably more than 700 m, and more preferably more than 800 m. Such a picture taking height can take pictures of a larger area, which is conducive to realizing rapid and efficient aerial photography.
[0054] In the thermal imaging aerial photography device of the utility model, the two thermal imaging cameras use infrared rays with a wavelength of 10 μm for thermal imaging aerial photography. When using infrared rays with a wavelength of 10 μm for thermal imaging aerial photography, a wider field of view can be achieved, and a higher resolution can also be achieved, in which case, rapid and efficient aerial photography can be realized at a high resolution.
[0055] The field of view angle of the thermal imaging camera is 20°-50°(H) and 15°-40°(V). It should be noted that the field of view angle 20°-50°(H) and 15°-40°(V) herein refers to the field of view angle of one camera. The camera with such a field of view angle can conveniently realize the field of view overlap rate of the thermal imaging aerial photography device of the utility model, thereby realizing rapid and efficient aerial photography. In addition, preferably, the field of view angle of one thermal imaging camera is 46.4°(H) and 37°(V). Under such a field of view angle, the field of view overlap rate of the thermal imaging aerial photography device of the utility model can be more simply realized, thereby realizing rapid and efficient aerial photography.
[0056] In the thermal imaging aerial photography device of the utility model, the combined resolution of the two thermal imaging cameras is 2200x1024. It should be noted that the resolution of the two thermal imaging cameras is not particularly limited, and the combined resolution of the two cameras after being combined and considering the field of view overlap rate is 2200x1024. Under such a resolution, aerial photography is performed at a higher shooting height, so that a larger range can be photographed in a shorter time, and therefore rapid and efficient aerial photography can be realized.
[0057] In the thermal imaging aerial photography device of the utility model, the focal length of the two thermal imaging cameras can be 15-25mm, preferably 19mm, and such a focal length can effectively ensure that the aerial photography device performs aerial photography operation at a high resolution.
[0058] As the thermal imaging camera in the thermal imaging aerial photography device of the utility model, there is no particular limitation, and the following cameras can be selected.
[0059] DJI Zenmuse H30T
[0060] Viewing angle and resolution: the equivalent focal length of the thermal imaging camera is 52mm, the DFOV is 45.2°, and the photograph and video resolution is 1280x1024.
[0061] Other advantages: integrated with a wide-angle camera, a zoom camera, a laser range finder and a near-infrared light supplementing five modules, and can realize visible light and thermal imaging picture display on the same screen by applying an advanced intelligent algorithm, supports three infrared gain modes of low gain mode, high gain mode and super clear mode, and the temperature measurement range is-20℃ to 1600℃.
[0062] In addition, the flight device in the thermal imaging aerial photography device of the utility model is a drone or a manned aircraft. Since the drone is more suitable for aerial photography in disaster sites such as forest fires and environments such as wild animal habitats which are relatively harsh, therefore, preferably, a drone is adopted.
[0063] Industrial practicability
[0064] The thermal imaging aerial photography device can be used for safety monitoring, forest fire prevention, power inspection and industrial detection, etc.
Claims
1. A thermal imaging aerial photography apparatus having a flight device and two thermal imaging cameras, the lenses of the thermal imaging cameras being mounted downwardly below the flight device, characterized in that, The overlap rate of the field of view of the two thermal imaging cameras is less than 10%.
2. The thermographic aerial survey device of claim 1, wherein, The overlap rate of the field of view of the two thermal imaging cameras is less than 5%.
3. The thermographic aerial survey device of claim 1, wherein, The angle between the normal lines of the lenses of the two thermal imaging cameras is less than 40°.
4. The thermographic aerial survey device of claim 1, wherein, The angle between the normal lines of the lenses of the two thermal imaging cameras is 36°.
5. The thermographic aerial survey device of claim 1, wherein, The boundaries of the field of view of the two thermal imaging cameras are in contact with each other but the field of view of the two thermal imaging cameras does not overlap.
6. The thermographic aerial survey device of claim 1, wherein, The two thermal imaging cameras use infrared rays with a wavelength of 10 μm for thermal imaging aerial photography.
7. The thermographic aerial survey device of claim 1, wherein, The field of view of the thermal imaging camera is 20°-50° (H) and 15°-40° (V).
8. The thermographic aerial survey device of claim 1, wherein, The field of view of the thermal imaging camera is 46.4° (H) and 37° (V).
9. The thermographic aerial survey device of claim 1, wherein, The combined resolution of the two thermal imaging cameras is 2200×1024.
10. The thermographic aerial survey device of claim 1, wherein, The flying device is a drone or a manned aircraft.