阅读说明：本技术 一种可视化液位检测装置及方法 (Visual liquid level detection device and method ) 是由 范钧 吕国皎 于 2021-03-25 设计创作，主要内容包括：本发明提出了一种可视化液位检测装置及方法。该可视化液位检测装置及方法中的检测装置包含相机阵列及漂浮目标物；所述相机阵列由多台相机在一维方向上排列而成；各相机拍摄图像的左右方向与相机阵列的排列方向保持一致；各相机镜头光轴方向平行；所述漂浮目标物密度小于所测液体,能漂浮于其上,其颜色与所测液体存在明显差异。该可视化液位检测装置及方法中的检测方法为通过相机阵列对漂浮目标物进行拍摄,并依托漂浮目标物的视差信息,分别按步骤计算获得漂浮目标物相对于各相机光轴的水平夹角、相机阵列到目标漂浮物距离在相机光轴方向的投影长度及漂浮目标物相对于相机阵列的垂直高度,即液面位置。(The invention provides a visual liquid level detection device and method. The detection device in the visual liquid level detection device and the visual liquid level detection method comprises a camera array and a floating target object; the camera array is formed by arranging a plurality of cameras in a one-dimensional direction; the left and right directions of the images shot by the cameras are consistent with the arrangement direction of the camera array; the optical axis directions of all camera lenses are parallel; the density of the floating target object is less than that of the measured liquid, the floating target object can float on the measured liquid, and the color of the floating target object is obviously different from that of the measured liquid. The detection method in the visual liquid level detection device and method is characterized in that a camera array is used for shooting a floating target object, and the horizontal included angle of the floating target object relative to each camera optical axis, the projection length of the distance from the camera array to the target floating object in the direction of the camera optical axis and the vertical height of the floating target object relative to the camera array, namely the liquid level position, are obtained through calculation according to the steps based on the parallax information of the floating target object.)

1. The utility model provides a visual liquid level detection device which characterized in that: the visual liquid level detection device comprises a camera array and a floating target object; the camera array is formed by arranging a plurality of cameras in a one-dimensional direction; the left and right directions of the images shot by the cameras are consistent with the arrangement direction of the camera array; the optical axis directions of all camera lenses are parallel; the density of the floating target object is less than that of the measured liquid, the floating target object can float on the measured liquid, and the color of the floating target object is obviously different from that of the measured liquid; the camera array shoots the floating target object, and the spatial position of the floating target object is obtained through calculation according to the position of the floating target object in the image shot by each camera, namely parallax information.

2. A visual liquid level detection apparatus as claimed in claim 1 wherein: the distance between cameras in the camera array is different.

3. A visual liquid level detection method is characterized in that: firstly, photographing the floating target object by using cameras in the camera array, and measuring a horizontal included angle of the floating target object relative to each camera optical axis; secondly, calculating the projection length of the distance from the camera array to the target floating object in the direction of the optical axis of the cameras by using the horizontal distance between the cameras and the horizontal included angle of the floating target object relative to the optical axis of each cameraDSpecifically, the horizontal distance between any two cameras is set asdThe horizontal included angles of the floating object relative to the optical axes of the two cameras are respectivelyγ _i、γ _jThen, then(ii) a Thirdly, in the vertical direction, utilizing the vertical included angle of the floating object relative to the optical axis of the cameraαPretilt angle of camera array with respect to horizontalβAnd the projection length of the distance from the camera array to the target floater in the direction of the optical axis of the cameraDCalculating the vertical height of the floating object relative to the camera arrayHI.e., the location of the liquid level, specifically,。

4. a visual liquid level detection method according to claim 3, characterized in that: and selecting a plurality of different camera combinations to measure the liquid level position, and averaging after data with errors exceeding three times of standard deviation is eliminated so as to obtain the liquid level position.

Technical Field

The invention relates to a photoelectric technology, in particular to a visual liquid level detection device and a visual liquid level detection method.

Background

The conventional liquid level detecting device usually uses a pressure sensor, a laser sensor, etc. to measure the liquid level. If the pressure sensor is arranged at the bottom of the liquid, the liquid level is measured through water pressure calculation, and the laser sensor emits laser beams to the liquid level and measures the position of the liquid level through reflected light. The detection device cannot visually reflect the liquid level condition, and cannot reflect the actual working state of the sensor. Therefore, the invention provides a visual liquid level detection device and a visual liquid level detection method, which can detect the liquid level height and display the liquid level condition in real time, and are convenient for a user to master the working condition of the detection device in real time.

Disclosure of Invention

The invention provides a visual liquid level detection device, which aims to solve the problems that the traditional detection device cannot visually reflect the position condition of a liquid level and cannot master whether the detection device normally works or not in real time.

The visual liquid level detection device comprises a camera array and a floating target.

The camera array is formed by arranging a plurality of cameras in a one-dimensional direction; the left and right directions of the images shot by the cameras are consistent with the arrangement direction of the camera array; the optical axis directions of the camera lenses are parallel.

The density of the floating target object is less than that of the measured liquid, the floating target object can float on the measured liquid, and the color of the floating target object is obviously different from that of the measured liquid.

The camera array shoots the floating target object, and the spatial position of the floating target object is obtained through calculation according to the position of the floating target object in the image shot by each camera, namely parallax information. The floating target is in the same horizontal plane with the liquid level, so that the position of the liquid level can be measured.

The image that the camera array gathered can directly utilize the display to demonstrate to the user grasps in real time and is detected liquid level position condition and detection device operating condition, when measuring numerical value and the liquid level position that directly shows on the display have obvious difference, or see on the display that the floating object sinks, detection personnel can learn detection device abnormal operation, and be convenient for in time repair, adjust.

Optionally, the distance between cameras in the camera array is different.

The present invention adopts the following method for liquid level detection.

Firstly, cameras in the camera array photograph the floating target object, and horizontal included angles of the floating target object relative to optical axes of the cameras are measured.

Secondly, calculating the distance between the camera array and the target floating object in the cameras by using the horizontal distance between the cameras and the horizontal included angle of the floating target object relative to the optical axis of each cameraProjected length in the direction of optical axisD. Specifically, the horizontal distance between any two cameras is set asdThe horizontal included angles of the floating object relative to the optical axes of the two cameras are respectivelyγ _i、γ _jThen, then。

Thirdly, in the vertical direction, utilizing the vertical included angle of the floating object relative to the optical axis of the cameraαPretilt angle of camera array with respect to horizontalβAnd the projection length of the distance from the camera array to the target floater in the direction of the optical axis of the cameraDCalculating the vertical height of the floating object relative to the camera arrayHI.e. the position of the liquid surface. In particular, the method comprises the following steps of,。

optionally, selecting other camera combinations according to the above steps, obtaining multiple sets of liquid level position measurement data simultaneously, and after eliminating data sets with errors exceeding three times of standard deviation, improving the accuracy of liquid level position detection by an averaging method.

In summary, the visual liquid level detection device and method provided by the invention can directly utilize the display to display the liquid level, so that the user can conveniently master the position condition of the detected liquid level and the working state of the detection device in real time, and simultaneously can obtain multiple groups of test data through multiple groups of cameras, thereby improving the accuracy of liquid level position detection.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings needed to be used in the embodiments will be briefly described below, it should be understood that the following drawings only illustrate some embodiments of the present invention and therefore should not be considered as limiting the scope, and for those skilled in the art, other related drawings can be obtained according to the drawings without inventive efforts.

FIG. 1 is a schematic structural diagram of the present invention.

Fig. 2 is a schematic diagram illustrating the principle of measuring the projection length of the target floating object distance in the optical axis direction of the camera according to the present invention.

FIG. 3 is a schematic view of the principle of measuring the vertical height of a liquid surface according to the present invention.

Icon: 100-a camera array; 200-a target float; 101-a first camera; 102-a second camera; 103-a third camera; 104-fourth camera.

It should be understood that the above-described figures are merely schematic and are not drawn to scale.

Detailed Description

Fig. 1 is a visual liquid level detection device provided by the embodiment. In the figure, the x-coordinate represents the horizontal direction in space, the y-coordinate represents the vertical direction in space, and z represents the direction perpendicular to the x-y plane.

Referring to fig. 1, the visual liquid level detecting apparatus includes a camera array 100 and a floating target 200.

Referring to fig. 2, the camera array is formed by arranging a first camera 101, a second camera 102, a third camera 103 and a fourth camera 104 in a horizontal one-dimensional direction; the left and right directions of the images shot by the cameras are consistent with the arrangement direction of the camera array; the optical axis directions of the camera lenses are parallel and are arranged at an angle of 20 degrees with the horizontal plane. The performance parameters of the first camera 101, the second camera 102, the third camera 103 and the fourth camera 104 are consistent, the shot images have a resolution of 3840 (H) × 2160 (V), the horizontal angle of view of the cameras is 80 degrees, and the vertical angle of view is 45 degrees. The distance between the first camera 101 and the second camera 102 isd ₁The distance between the second camera 102 and the third camera 103 isd ₂The distance between the third camera 103 and the fourth camera 104 isd ₃。

The density of the floating target object 200 is less than that of the measured liquid, the floating target object can float on the measured liquid, and the red paint coated on the surface of the floating target object is obviously different from that of the measured liquid.

The camera array 100 photographs a floating object, and calculates and obtains the spatial position of the floating object 200 according to the positions of the floating object 200 in images photographed by the first camera 101, the second camera 102, the third camera 103 and the fourth camera 104, i.e., parallax information. Since the floating target 200 is at the same level as the liquid surface, the position of the liquid surface can be measured.

The image collected by the camera array 100 can be displayed by the display directly, so that a user can conveniently master the position condition of the detected liquid level and the working state of the detection device in real time, when the measured value is obviously different from the liquid level position directly displayed on the display, or when a floating target object is seen on the display to sink, a detection person can know that the detection device works abnormally, and timely repair and adjustment are facilitated.

Specifically, referring to fig. 2, the present invention adopts the following method for liquid level detection.

Referring to fig. 2, firstly, the cameras in the camera array 100 take pictures of the floating target 200, and measure the horizontal angle of the floating target 200 relative to the optical axis of each camera.

Specifically, the floating target 200 is in the pixel array in the image captured by the first camera 101m ₁Line, firstn ₁Column position, horizontal angle relative to the optical axisγ ₁Should be 80 × (1920-n ₁) 3840 degrees; the floating object 200 is in the pixel array in the image taken by the second camera 102m ₂Line, firstn ₂Column position, horizontal angle relative to the optical axisγ ₂Should be 80 × (1920-n ₂) 3840 degrees; the floating target 200 is in the pixel array in the image taken by the third camera 103m ₃Line, firstn ₃Column position, horizontal angle relative to the optical axisγ ₃Should be 80 × (1920-n ₃) 3840 degrees; the floating object 200 is in the pixel array in the image taken by the fourth camera 104m ₄Line, firstn ₄Column position, horizontal angle relative to the optical axisγ ₄Should be 80 × (1920-n ₄) 3840 degrees. The left and right directions of the images taken by the cameras and the arrangement direction of the camera arrayThe consistency is kept, and the operation is carried out,m ₁、m ₂、m ₃andm ₄should be equal.

Referring to fig. 2, the projection length of the distance from the camera array 100 to the target floating object 200 in the direction of the optical axis of the camera is calculated by using the horizontal distance between the cameras and the horizontal angle between the floating object and the optical axis of the camerasD. Specifically, the horizontal distance between any two cameras is set asdThe horizontal included angles of the floating target object 200 relative to the optical axes of the two cameras are respectivelyγ _i、γ _jThen, then。

Specifically, taking the first camera 101 and the second camera 102 as an example, the horizontal angles of the floating target 200 relative to the optical axis of the first camera 101 measured by the first step are respectivelyγ ₁A horizontal angle with respect to the optical axis of the second camera 102 isγ ₂The first camera 101 and the second camera 102 are spaced apart by a distance ofd ₁Then there is the projection length of the distance from the camera array 100 to the target floating object 200 in the direction of the optical axis of the camera。

Thirdly, referring to fig. 3, in the vertical direction, the vertical included angle of the floating target 200 with respect to the optical axis of the camera is usedαPretilt angle of camera array 100 with respect to horizontalβAnd the projection length of the distance from the camera array 100 to the target floater 200 in the direction of the optical axis of the cameraDCalculating the vertical height of the floating target 200 relative to the camera array 100HI.e. the position of the liquid surface. In particular, the method comprises the following steps of,。

specifically, the floating object 200 is located at the pixel array in the image captured by the first camera 101m ₁Lines in the image captured by the second camera 102Pixel array them ₂A line is formed bym ₁、m ₂、m ₃Andm ₄equal, the vertical included angle of the floating object relative to the optical axis of the cameraαShould be 45 × (1080-m ₁) 2160 deg. The optical axes of the camera lenses are parallel and are arranged at 20 degrees to the horizontal plane, i.e. the pretilt angle of the camera array relative to the horizontal directionβIs 20 degrees. The vertical height of the floating target 200 relative to the camera array 100H ₁₂Ying YouI.e. the position of the liquid surface. WhereinH ₁₂The subscript 12 indicates that the data is jointly measured by the first camera 101 and the second camera 102.

Further, according to the above steps, the combination of the first camera 101 and the third camera 103 is selected to obtainH ₁₃(ii) a The combination of the first camera 101 and the fourth camera 104 is selectedH ₁₄(ii) a The combination of the second camera 102 and the third camera 103 is selectedH ₂₃(ii) a The combination of the second camera 102 and the fourth camera 104 is selectedH ₂₄(ii) a The combination of the third camera 103 and the fourth camera 104 is selectedH ₃₄. The accuracy of the liquid level position detection can be improved by averaging the data sets with errors exceeding three times of the standard deviation among the plurality of sets of measurement data.

In summary, the visual liquid level detection device and method provided by the invention can directly utilize the display to display the liquid level, so that the user can conveniently master the position condition of the detected liquid level and the working state of the detection device in real time, and simultaneously can obtain multiple groups of test data through multiple groups of cameras, thereby improving the accuracy of liquid level position detection.