Dynamic liquid testing device

Abstract

The invention relates to a dynamic liquid testing device. The dynamic liquid testing device comprises a binocular vision camera, a data processing module, a box body in which liquid is sealed and stored, a shaking mechanism used for shaking the box body to drive the liquid to shake, and at least three non-collinear liquid level detection components located in the liquid. Each liquid level detection component comprises a telescopic rod fixed to the inner bottom wall of the box body and a floating ball driving the telescopic end to stretch out and draw back relative to the fixed end through buoyancy. The binocular vision camera collects liquid level images in real time and obtains the three-dimensional coordinates of each floating ball in each frame of liquid level image in a three-dimensional space coordinate system, the data processing module identifies the three-dimensional coordinates of each floating ball in each frame of liquid level image in the three-dimensional space coordinate system, and the three-dimensional images of the corresponding liquid level are drawn by connecting lines. The three-dimensional images of different frames are continuously output, a three-dimensional real-time dynamic change image of the liquid level is formed, and the technical problem that in the prior art, only the liquid level section change of the liquid in the closed box instead of the liquid level three-dimensional change can be captured by observing two-dimensional image information is solved.

Description

Technical Field

[0001] The present application relates to the technical field of dynamic liquid measurement, and in particular to a dynamic liquid testing device. Background Art

[0002] Liquids undergo dynamic changes under external stimulation or disturbance, and their center of gravity also shifts accordingly. Research on these dynamic changes is of considerable practical significance. For example, in aviation, as demands for aircraft range and endurance increase, the proportion of liquid fuel carried by aircraft continues to rise, making fuel a significant contributor to aircraft weight. During flight, fuel sloshes within the tank, causing changes in its distribution within the tank and, consequently, affecting the aircraft's center of gravity. Pilots or flight control software must monitor these changes in the aircraft's center of gravity in real time and adjust flight controls accordingly to maintain aircraft stability. For small aircraft or drones, especially those with low weight, changes in the fuel's center of gravity can have a greater impact on flight attitude, requiring more precise capture of the dynamic changes in the liquid's center of gravity. Automatically identifying changes in the center of gravity caused by liquid sloshing and automatically correcting flight attitude would significantly reduce the pilot's experience requirements. In aerospace, significant sloshing of liquid fuel during flight can also adversely affect flight attitude control. In the field of ship transportation, when the liquid in the cargo hold of a large liquid cargo ship sways, it will have a huge impact on the cabin structure. It is necessary to analyze the impact load generated by the dynamic liquid and adopt targeted designs such as reinforcing baffles to ensure safety.

[0003] Since the dynamic changes of the liquid in the tank are constrained in multiple directions by the closed box structure, usually only the liquid surface will change significantly with shaking. Therefore, it is necessary to pay attention to the changes in the liquid surface when judging the center of gravity. In order to better observe the changes in the liquid surface when the liquid shakes, researchers will simulate a series of dynamic liquid tests. During the test, transparent materials such as plexiglass are usually used to make a scaled-down test tank, and a camera is used to shoot the initial liquid surface image and the liquid surface image after shaking the tank from the side through the plexiglass. After comparative analysis, the dynamic changes of the liquid surface are judged. However, studying the spatial changes of the liquid surface through two-dimensional image information can only infer the cross-sectional shape of the liquid in the closed box, and cannot form a three-dimensional liquid surface change. Therefore, the accuracy of the existing methods for inferring the geometric center of gravity position and the three-dimensional spatial shape of the liquid is low, which will also affect the effectiveness of subsequent research such as flight control strategy design and liquid tank anti-impact structure design. Summary of the Invention

[0004] The present invention provides a dynamic liquid testing device to solve the technical problem that the existing method of observing two-dimensional image information can only capture the cross-sectional changes of the liquid surface in a closed box but not the three-dimensional changes of the liquid surface.

[0005] The present invention provides a dynamic liquid testing device, including a box, a shaking mechanism, a liquid level detection component, a binocular vision camera, and a data processing module. The box is sealed to store liquid; the shaking mechanism is used to shake the box to drive the liquid to shake; the liquid level detection component is located in the liquid and there are at least three non-collinear liquid level detection components, each of which includes a float and a telescopic rod; the fixed end of the telescopic rod is upright and fixed to the inner bottom wall of the box, and the telescopic end of the telescopic rod is fixed to the float, which drives the telescopic end to extend and retract relative to the fixed end through buoyancy, and the static liquid level of the liquid is located within the telescopic stroke range of the telescopic rod; the binocular vision camera is used to capture liquid surface images in real time and obtain the three-dimensional coordinates of each float in each frame of the liquid surface image in a three-dimensional space coordinate system; the data processing module is used to identify the three-dimensional coordinates of each float in each frame of the liquid surface image in a three-dimensional space coordinate system, connect lines to draw a three-dimensional image of the corresponding liquid surface, and continuously output three-dimensional images of different frames to form a three-dimensional real-time dynamic changing image of the liquid surface.

[0006] In some embodiments, the float is made of polyurethane foam.

[0007] In some of the embodiments, the data processing module combines the internal and external parameters of the binocular vision camera obtained in advance with the camera to convert the two-dimensional pixel coordinates of the float on the liquid surface image into camera coordinate system coordinates, and further converts them into box coordinate system coordinates based on the installation position of the binocular vision camera in the box to obtain the spatial three-dimensional coordinates of the float.

[0008] In some of the embodiments, the fixed end and the output end of the telescopic rod are both hollowed out, and the fixed end of the telescopic rod is vertically rotatably mounted on the inner bottom wall of the box.

[0009] In some embodiments, the box is provided with an observation window, and the binocular vision camera is fixedly mounted on the outer wall of the box to obtain the liquid surface image through the observation window. Preferably, the inner wall of the observation window is covered with a transparent hydrophobic film.

[0010] In some embodiments, the binocular vision camera is fixedly mounted on the outer wall of the box, the box is made of a transparent material, and the binocular vision camera obtains the liquid surface image through the box. Preferably, the inner wall of the box is covered with a transparent hydrophobic film.

[0011] In some embodiments, the hydrophobic film is made of silicon dioxide.

[0012] In some embodiments, the dynamic liquid testing device further comprises an irradiation lamp fixedly mounted on the outer wall of the box, the outer surface of the float is coated with a reflective layer, and the binocular vision camera takes an image of the float illuminated by the irradiation lamp.

[0013] In some embodiments, two irradiation lamps are provided, and the two irradiation lamps are symmetrically distributed along the diagonal line of the top edge of the box.

[0014] In some embodiments, the rocking mechanism includes a rocking platform and four telescopic hydraulic rods. The box is fixedly mounted on the upper surface of the rocking platform. The four telescopic hydraulic rods drive the rocking platform to rock through their respective different telescopic amounts.

[0015] In some embodiments, the dynamic liquid testing device further includes a sway control module, which is loaded on the mobile terminal and is used to control the extension and retraction of the four telescopic hydraulic rods.

[0016] In some of the embodiments, the data processing module is loaded into the binocular vision camera.

[0017] In some embodiments, the data processing module is loaded on the mobile terminal and is in wireless communication with the binocular vision camera.

[0018] Compared with the related art, the present invention has the following beneficial effects:

[0019] By installing a liquid level detection component in the tank, using a shaking mechanism to drive the liquid to shake, and using a binocular vision camera to capture real-time images of the liquid level in the tank and obtain the three-dimensional spatial coordinates of each float in each frame of the image, the data processing module then connects the three-dimensional coordinates of all floats in the same frame of the liquid level image to draw a stereo image of the corresponding liquid level. Finally, stereo images of different frames are continuously output to form a three-dimensional real-time dynamic change of the liquid level. This solves the existing technical problem that observing two-dimensional image information can only capture the cross-sectional changes of the liquid level in a closed tank, rather than the three-dimensional changes of the liquid level. In addition, the number of coordinates collected can be increased conveniently and cost-effectively by adding floats. This improves the accuracy of dynamic liquid change detection, such as liquid surface shape reconstruction and liquid center of gravity position calculation, and is beneficial to the setting of aircraft flight control strategies and the improvement of ship tank structure design.

[0020] The details of one or more embodiments of the present application are set forth in the following drawings and description to make other features, objects, and advantages of the present application more readily apparent. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 is a three-dimensional diagram of the dynamic liquid test device proposed in this embodiment;

[0022] Figure 2 is a partial three-dimensional diagram of the liquid level detection component in this embodiment;

[0023] Figure 3 This is a simulated imaging effect diagram of the liquid surface determined by three floats;

[0024] Figure 4It is a schematic diagram of the coordinates of three floating balls in the three-dimensional space coordinate system;

[0025] Figure 5 It is a liquid surface simulation imaging effect diagram determined by multiple floats;

[0026] Figure 6 It is a coordinate diagram of multiple floats in a three-dimensional space coordinate system.

[0027] In the figure: 1. Box body; 2. Liquid level detection component; 21. Float; 22. Telescopic rod; 23. Rotating shaft; 31. Binocular vision camera; 32. Illumination lamp; 33. Data processing module; 4. Shaking mechanism; 41. Shaking platform; 42. Shaking control module; 43. Telescopic hydraulic rod. DETAILED DESCRIPTION

[0028] In order to more clearly understand the purpose, technical solutions and advantages of the present application, the present application is described and illustrated below in conjunction with the accompanying drawings and embodiments.

[0029] Unless otherwise defined, the technical terms or scientific terms involved in this application should have the general meaning understood by people with ordinary skills in the technical field to which this application belongs. The words "one", "an", "a", "the", "these" and the like in this application do not indicate quantitative restrictions, and they can be singular or plural. The terms "include", "comprise", "have" and any variants thereof involved in this application are intended to cover non-exclusive inclusions; for example, a process, method and system, product or device comprising a series of steps or modules (units) is not limited to the listed steps or modules (units), but may include unlisted steps or modules (units), or may include other steps or modules (units) inherent to these processes, methods, products or devices. The words "connect", "connected", "coupled" and the like involved in this application are not limited to physical or mechanical connections, but may include electrical connections, whether direct or indirect. The "plurality" involved in this application refers to two or more. "And / or" describes the relationship between related objects, indicating that three possible relationships exist. For example, "A and / or B" can represent: A exists alone, A and B exist simultaneously, and B exists alone. Generally, the character " / " indicates that the related objects are in an "or" relationship. The terms "first," "second," "third," etc. used in this application are only used to distinguish similar objects and do not represent a specific ordering of the objects.

[0030] See also Figure 1, which is a dynamic liquid testing device provided in this embodiment, the device includes a shaking mechanism 4, a box 1, at least three non-collinear liquid level detection components 2 located in the liquid, a binocular vision camera 31, an irradiation lamp 32, a data processing module 33 and a shaking control module 42.

[0031] The box body 1 may be rectangular and used to enclose and store liquid for testing. The box body 1 may be made of a transparent material. The inner wall of the box body 1 may be covered with a transparent hydrophobic film. The material of the hydrophobic film may be silicon dioxide.

[0032] The shaking mechanism 4 can create shaking, which is used to shake the box body 1 and drive the liquid to shake. In this embodiment, the box body 1 is installed on the shaking mechanism 4. The shaking mechanism 4 may include a shaking platform 41 and four telescopic hydraulic rods 43. The box body 1 can be fixedly installed on the upper surface of the shaking platform 41, and the four telescopic hydraulic rods 43 can be fixedly installed and evenly distributed on the lower surface of the shaking platform 41. The shaking control module 42 can be loaded on a mobile terminal (app, tablet, computer, etc.) and is used to control the extension and retraction of the four telescopic hydraulic rods 43. The four telescopic hydraulic rods 43 can be uniformly controlled by the shaking control module 42. The staff can change and record the extension and retraction status of each telescopic hydraulic rod 43 in real time through the shaking control module 42 on the mobile terminal, so that the shaking platform 41 can simulate various posture and movement changes of an aircraft fuel tank or a cargo ship tank.

[0033] Please combine Figure 2 Each liquid level detection component 2 can include a float 21 and a telescopic rod 22. The fixed end (lower end) of the telescopic rod 22 can be vertically fixed to the inner bottom wall of the housing 1, and the output end of the telescopic rod 22 can be fixedly connected to the bottom of the float 21. The float 21 is driven to expand and contract relative to the fixed end by buoyancy. Therefore, the density of the material used to make the float 21 must not only be lower than the density of the test liquid, but also the buoyancy of the float 21 must be greater than the sum of the weight of the float 21 and the telescopic end of the telescopic rod 22. In this embodiment, the float 21 can be made of polyurethane foam, which has low density, high compressive strength, and low water absorption. It can provide high buoyancy, and the density and strength of the foam can be adjusted as needed to meet different usage requirements. Therefore, the float 21 can float on the surface of the liquid. When the liquid sloshes and the liquid level changes, the height of the float 21 relative to the bottom wall of the housing 1 can change with the liquid level. Similarly, the output end of the telescopic rod 22 can move vertically in the liquid together with the float 21. For example, if the liquid level rises at a certain point, the float 21 at that point will drive the telescopic rod 22 to extend under the action of buoyancy. If the liquid level drops, the telescopic rod will shorten under the action of gravity of the float 21 and the telescopic end of the telescopic rod 22. In addition, the telescopic rod 22 can limit the horizontal movement of the float 21, preventing the float 21 from floating around with the shaking liquid surface or accumulating to one side of the liquid surface, resulting in the float 21 lacking coverage of the entire liquid surface.

[0034] In order to make it easier for the float 21 to drive the output end of the telescopic rod 22 to float up, the output end of the telescopic rod 22 can be hollowed out (to reduce the gravity of the output end of the telescopic rod 22), and in order to minimize the obstruction effect of the telescopic rod 22 on the dynamic liquid, the fixed end of the telescopic rod 22 can also be hollowed out (a flow opening is opened on the side wall), and the liquid can freely pass through the flow opening when flowing. The fixed end of the telescopic rod 22 can be vertically rotatably mounted on the inner bottom wall of the box body 1 through the rotating shaft 23, so that the telescopic rod 22 can rotate freely with the flow of the liquid, further reducing the obstruction effect on the dynamic liquid.

[0035] The binocular vision camera 31, which can be a Hikvision iDS-2CD6810F / C model, is used to capture liquid surface images in real time and obtain the three-dimensional coordinates of each float 21 in the three-dimensional camera coordinate system for each frame of the liquid surface image. The three-dimensional coordinates of each float 21 in the camera coordinate system are obtained by simultaneously capturing a liquid surface image frame with each of the two cameras of the binocular vision camera 31. The two liquid surface image frames are analyzed to obtain the two two-dimensional pixel coordinates of each float 21 in the two liquid surface image frames. The three-dimensional coordinates of each float 21 are then combined with the internal and external parameters of the binocular vision camera 31 to obtain the three-dimensional coordinates of each float 21.

[0036] Specifically, first observe the two frames of liquid surface images taken by the two cameras in the binocular vision camera 31, select any one of the floats 21, and intuitively obtain the image physical coordinates of the float 21 in each frame of the liquid surface image, that is, the two two-dimensional pixel coordinates (u1, v1) and (u2, v2). Use binocular imaging technology to compare the two frames of liquid surface images, combine the two two-dimensional pixel coordinates and the binocular vision camera 31 internal and external parameter conversion matrix K1, K2 and focal length f1, f2 obtained in advance through calibration, and then bring in the rotation matrices R1, R2 and translation vectors T1, T2 of the two cameras to perform rigid body transformation. The transformation relationship formula is as follows:

[0037]

[0038] Combining the above two equations, the three-dimensional coordinates (X P ,Y P ,Z P ), and so on, the three-dimensional coordinates of the remaining floats 21 can be obtained, and then these three-dimensional coordinates are sent to the data processing module 33.

[0039] The data processing module 33 is used to draw the three-dimensional coordinates of all the floats 21 in the same frame of liquid surface image into a three-dimensional image of the corresponding liquid surface in real time, and continuously output the three-dimensional images of different frames to form a three-dimensional real-time dynamic change of the liquid surface. Figure 3 and Figure 4, the three-dimensional coordinates of the three floating balls 22 in the space coordinate system of the box 1 are obtained from a certain frame of image (X P1 ,Y P1 ,Z P1 )、(X P2 ,Y P2 ,Z P2 )、(X P3 ,Y P3 ,Z P3 ), then the data processing module 33 can obtain a three-dimensional cross section through these three non-collinear points, thereby obtaining a simulated imaging effect diagram of the liquid surface (i.e., a three-dimensional image corresponding to the liquid surface of this frame). This scenario is applicable to the case where the liquid surface is tilted in only one direction. For some complex liquid surface situations (such as the liquid sways back and forth in the box 1 to form irregular waves, please combine Figure 5 and Figure 6 At this time, the three-dimensional coordinates (P1, P2, P3...Pn) of multiple (far more than three) floats 22 are connected and drawn together to form a three-dimensional image of the corresponding liquid surface in the current frame. Finally, the three-dimensional images of different frames are continuously output to form a three-dimensional real-time dynamic change of the liquid surface.

[0040] The data processing module 33 can be loaded into the binocular vision camera 31, and the staff only needs to operate around the binocular vision camera 31, which is simple and convenient. In other embodiments, the data processing module 33 can be loaded into a mobile terminal (such as a mobile phone app, tablet, computer, etc.) and communicate wirelessly with the binocular vision camera 31 (such as Wi-Fi, Bluetooth), so that the staff can observe the three-dimensional real-time dynamic changes of the final liquid level through these mobile terminals.

[0041] In order to prevent the liquid from sticking to the camera lens of the binocular vision camera 31 when it shakes, the binocular vision camera 31 can be fixedly installed on the outer wall of the box 1, and shooting can be done through a transparent observation window or a box 1 made of glass can be used. The inner wall of the observation window or the box 1 can be covered with a hydrophobic film. The material of the hydrophobic film can be silicon dioxide, which can be prepared into a transparent hydrophobic film through a sol-gel method, etc., to prevent the liquid from adhering to the inner wall of the box 1 after high-frequency shaking, thereby affecting the quality of the image taken by the binocular vision camera 31.

[0042] In order to more clearly observe the position of each float 21 in the liquid surface image, the illumination lamp 32 can be fixedly installed on the outer wall of the box body 1, and the float 21 can be coated with a reflective coating. The binocular vision camera (31) takes an image of the float 21 illuminated by the illumination lamp 32. The emission wavelength of the illumination lamp 32 light source can be designed according to the difference in the absorption spectrum of the test liquid medium and the material of the float 21. Usually, a wavelength with a higher absorption degree of the test liquid can be selected so that the light emitted by the illumination lamp 32 is absorbed by the liquid in the box body 1 and can be reflected by the float 21. With the illumination of the illumination lamp 32, the liquid surface on the liquid surface image appears dark and the float 21 is very bright (refer to Figure 3 、 Figure 5 As shown), the accuracy of obtaining the three-dimensional space coordinates of the float 21 is improved.

[0043] There can be two irradiation lamps 32, and the two irradiation lamps 32 can be symmetrically distributed along the diagonal lines of the top edge of the box body 1. The two irradiation lamps 32 can expand the irradiation range of the liquid surface, avoid the blind spots that may be caused by the shaking of the liquid surface, and prevent the appearance of some shadow parts in the generated liquid surface image. Similarly, two binocular vision cameras 31 can also be set, which not only expands the shooting range but also allows the three-dimensional coordinates of the float 21 to be observed from two angles. If the image taken by a binocular vision camera 31 is flawed and not clear enough, the other binocular vision camera 31 is activated to retake the image, and the two sets of three-dimensional coordinates measured by the two binocular vision cameras 31 can be used for comparison. If the error is small, one of the three-dimensional coordinates can be selected to continue the test. If the error is large, the data is discarded and retaken.

[0044] In summary, by installing the liquid level detection component 2 in the box 1, and then using the shaking mechanism 4 to drive the liquid to shake, and using the binocular vision camera 31 to collect the liquid level image in the box 1 in real time and obtain the three-dimensional spatial coordinates of each float 21 in each frame image, and then using the data processing module 33 to connect the three-dimensional coordinates of all floats 21 in the same frame liquid level image to draw a three-dimensional image of the corresponding liquid surface, and finally continuously outputting three-dimensional images of different frames to form a three-dimensional real-time dynamic change of the liquid surface, the existing technical problem of relying on observing two-dimensional image information to only capture the liquid surface cross-sectional changes in the closed box rather than the three-dimensional changes of the liquid surface is solved. The accuracy of dynamic liquid change detection such as liquid surface shape reconstruction and liquid center of gravity position solution is improved, which is beneficial to the setting of aircraft flight control strategy and the improvement of ship tank structure design.

[0045] It should be noted that the above modules can be functional modules or program modules, and can be implemented through software or hardware. For modules implemented through hardware, the above modules can be located in the same processor; or the above modules can be located in different processors in any combination.

[0046] It should be understood that the specific embodiments described herein are only used to explain this application and are not used to limit it. Based on the embodiments provided in this application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0047] Obviously, the accompanying drawings are merely examples or embodiments of the present application. A person skilled in the art can also apply the present application to other similar situations based on these drawings without inventive effort. Furthermore, it is understandable that, although the work involved in this development process may be complex and lengthy, certain design, manufacturing, or production changes based on the technical content disclosed in this application are merely routine technical means for a person skilled in the art and should not be considered to constitute a deficiency in the disclosure of the present application.

Claims

1. A dynamic liquid testing device, characterized in that: include: A box (1) encloses and stores liquid; A shaking mechanism (4) is used to shake the box (1) to drive the liquid to shake; At least three non-collinear liquid level detection components (2) are located in the liquid, each liquid level detection component (2) comprising a float (21) and a telescopic rod (22); the fixed end of the telescopic rod (22) is upright and fixed on the inner bottom wall of the box (1); the telescopic end of the telescopic rod (22) is fixed to the float (21); the float (21) drives the telescopic end to extend and retract relative to the fixed end through buoyancy, and the static liquid level of the liquid is located within the telescopic travel range of the telescopic rod (22); A binocular vision camera (31) is used to collect liquid surface images in real time and obtain the three-dimensional coordinates of each float (21) in each frame of the liquid surface image in a three-dimensional space coordinate system; The data processing module (33) is used to identify the three-dimensional coordinates of each float (21) in the three-dimensional space coordinate system in each frame of the liquid surface image, draw lines to form a three-dimensional image of the corresponding liquid surface, and continuously output the three-dimensional images of different frames to form a three-dimensional real-time dynamic change image of the liquid surface.

2. The dynamic liquid testing device according to claim 1, characterized in that: The material of the float (21) is polyurethane foam; And / or, the data processing module (33) combines the camera internal and external parameters of the binocular vision camera (31) obtained by pre-calibration to convert the two-dimensional pixel coordinates of the float on the liquid surface image into camera coordinate system coordinates, and further converts them into box coordinate system coordinates in combination with the installation position of the binocular vision camera (31) in the box (1) to obtain the spatial three-dimensional coordinates of the float (21).

3. The dynamic liquid testing device according to claim 1, characterized in that: The fixed end and the output end of the telescopic rod (22) are both hollow-out designs, and the fixed end of the telescopic rod (22) is vertically rotatably mounted on the inner bottom wall of the box body (1).

4. The dynamic liquid testing device according to claim 1, characterized in that: The binocular vision camera (31) is fixedly mounted on the outer wall of the box (1); the box (1) is provided with an observation window, and the binocular vision camera (31) obtains the liquid surface image through the observation window; or the box (1) is made of a transparent material, and the binocular vision camera (31) obtains the liquid surface image through the box (1).

5. The dynamic liquid testing device according to claim 4, characterized in that: The inner wall of the observation window or the inner wall of the box body (1) is covered with a transparent hydrophobic film.

6. The dynamic liquid testing device according to claim 5, characterized in that: The material of the hydrophobic membrane is silicon dioxide.

7. The dynamic liquid testing device according to claim 1, characterized in that: The dynamic liquid test device further comprises an irradiation lamp (32), the outer surface of the float (21) is coated with a reflective layer, and the binocular vision camera (31) takes an image of the float (21) irradiated by the irradiation lamp (32).

8. The dynamic liquid testing device according to claim 7, characterized in that: Two irradiation lamps (32) are provided, and the two irradiation lamps (32) are symmetrically distributed along the diagonal lines of the top edge of the box body (1).

9. The dynamic liquid testing device according to claim 1, characterized in that: The shaking mechanism (4) comprises a shaking platform (41) and four telescopic hydraulic rods (43). The box (1) is fixedly mounted on the upper surface of the shaking platform (41). The four telescopic hydraulic rods (43) drive the shaking platform (41) to shake through their respective different telescopic amounts.

10. The dynamic liquid testing device according to claim 1, characterized in that: The data processing module (33) is loaded into the binocular vision camera (31); And / or, the data processing module (33) is loaded on the mobile terminal and communicates wirelessly with the binocular vision camera (31).

Images