Glassware and laboratory equipment for measuring liquid volumes

Abstract

The application relates to a glass instrument for measuring liquid volume and experimental instrument equipment; the experimental instrument equipment comprises a glass instrument for measuring liquid volume, and the glass instrument is provided with optical coding marks; a terminal device comprises a camera, one or more processors, a memory, and one or more application programs stored in the memory; the one or more application programs are configured to execute the following method by the one or more processors: calling the camera to shoot a video image of the glass instrument in real time, identifying liquid level change images and corresponding volume readings of the liquid from the video image according to the optical coding marks, correcting the volume readings to obtain actual readings, generating real-time reading information according to the actual readings, and displaying the real-time reading information at the liquid level position according to the optical coding marks; the technical scheme improves the teaching efficiency and effect of titration experiments.

Description

Technical Field

[0001] This application relates to the field of experimental instrument and equipment technology, and in particular to a glass instrument and experimental instrument and equipment for measuring the volume of liquids. Background Technology

[0002] In chemical experiments, glassware used to measure the volume of liquids is essential. These glasswares include graduated cylinders, measuring cups, volumetric flasks, burettes, pipettes, etc. Each of these instruments has its own characteristics and is suitable for different experimental needs.

[0003] In a laboratory environment, accurate readings of liquid volume are crucial for chemical analysis. When taking readings of these glass instruments, it is necessary to accurately select the observation position, accurately identify the liquid level, and consider the effects of glass refraction. Therefore, in order to improve the operator's skill level, extensive training is required to master the relevant experience.

[0004] In experimental teaching, in order to train students' reading ability, teachers need to repeatedly guide students to correct their reading methods and constantly calibrate the measurement readings, which takes up a lot of teaching time. Moreover, this model makes it difficult to achieve standardized teaching, which seriously affects teaching efficiency and effectiveness. Summary of the Invention

[0005] To address one of the aforementioned shortcomings, this application provides a glass instrument and experimental apparatus for measuring liquid volume, thereby improving the teaching efficiency and effectiveness of reading glass instruments used in chemical experiments.

[0006] An experimental instrument and equipment, comprising:

[0007] A glass instrument for measuring liquid volume, wherein the glass instrument is provided with optically coded markings;

[0008] A terminal device, the terminal device comprising: a camera, one or more processors, a memory, and one or more applications stored in the memory;

[0009] The one or more applications are configured to be executed by the one or more processors as follows: calling a camera to capture video images of the glass instrument in real time; identifying liquid level changes and their corresponding volume readings from the video images based on the optically encoded markers; correcting the volume readings to obtain actual readings; generating real-time reading information based on the actual readings; and displaying the real-time reading information at the liquid level position based on the optically encoded markers.

[0010] In one embodiment, the terminal device is a smartphone, a computer device connected to a camera, or a wearable device; wherein the one or more applications are installed on the terminal device in the form of an App.

[0011] In one embodiment, the one or more applications are configured to execute the following methods by the one or more processors:

[0012] The camera pose parameters of the camera are calculated based on the liquid level change image, the camera parameters of the camera, and the instrument parameters of the glass instrument; the volume reading is corrected based on the refractive index parameters of the glass instrument tube wall and the camera pose parameters to obtain the actual reading.

[0013] In one embodiment, the one or more applications are configured to execute the following methods by the one or more processors:

[0014] Acquire each frame of the video image showing changes in the liquid level, input the liquid level change images into a pre-trained deep learning model to determine the liquid level position; perform edge detection on the liquid level position to identify the concave line of the liquid level; determine the volume reading based on the lowest point of the concave line of the liquid level and the scale lines of the glass instrument.

[0015] In one embodiment, the one or more applications are configured to execute the following methods by the one or more processors:

[0016] The glass instrument image is identified from the liquid level change image; the camera parameters of the camera and the instrument parameters of the glass instrument are obtained; the coordinate parameters of the reference point on the glass instrument image are determined according to the instrument parameters; and the camera pose parameters of the camera are calculated according to the coordinate parameters and the camera parameters.

[0017] In one embodiment, when calculating the camera pose parameters of the camera, the one or more applications are configured to be executed by the one or more processors as follows:

[0018] Multiple reference points are selected on the image of the glass instrument; the first coordinates of each reference point in the coordinate system are determined according to the instrument parameters; the rotation matrix and translation vector of the camera are calculated according to the first coordinates and camera parameters; and the relative position and shooting angle between the camera and the glass instrument are determined according to the rotation matrix and translation vector.

[0019] In one embodiment, the one or more applications are configured to execute the following methods by the one or more processors:

[0020] Obtain the second coordinate of the liquid surface position on the coordinate system; obtain the third coordinate of the camera on the coordinate system based on the relative position; determine the refractive index parameter of the glass instrument tube wall based on the material used by the glass instrument; construct an optical path model based on the shooting angle, the second coordinate, the third coordinate, and the refractive index parameter; and perform tube wall refractive index compensation on the volume reading based on the optical path model to obtain the actual reading of the glass instrument.

[0021] In one embodiment, the one or more applications are configured to execute the following methods by the one or more processors:

[0022] The line-of-sight deviation angle is calculated based on the first coordinate of the reference point in the glass instrument image and the position of the concave line of the liquid surface in the burette image. The adjustment direction of the camera is then calculated based on the deviation angle, and corresponding prompt information is generated and displayed.

[0023] In one embodiment, the one or more applications are configured to execute the following methods by the one or more processors:

[0024] Real-time reading information is generated based on the actual readings of each frame of liquid level change image; the optical coding mark is identified using tracking technology, and the target display position of the real-time reading information is determined based on the optical coding mark; the real-time reading information is displayed according to the target display position.

[0025] In one embodiment, the glass instrument is a burette; the one or more applications are configured to execute the following methods by the one or more processors:

[0026] The corresponding solution parameters are obtained from the actual readings identified in each frame of the liquid level change image; a titration curve is fitted on the titration curve graph based on the actual readings and their corresponding solution parameters; and the titration curve is dynamically displayed on the display interface.

[0027] In one embodiment, the glass instrument is a burette; the one or more applications are configured to execute the following methods by the one or more processors:

[0028] The reading image of the potentiometric titrator is captured in real time using a camera, and the corresponding reading is identified from the reading image. When the reading reaches the titration endpoint, a titration endpoint prompt is generated, and the reading image and the titration endpoint prompt are displayed in real time.

[0029] In one embodiment, the glass instrument is a burette; the one or more applications are configured to execute the following methods by the one or more processors:

[0030] A camera is used to capture real-time images of the sample solution inside the conical flask, and the color of the sample solution is identified from the image. When a color change is detected in the sample solution with added indicator, a titration endpoint prompt is generated and displayed in real-time at the location of the conical flask.

[0031] A glass instrument for measuring liquid volume, the surface of which is printed with optically coded markings; the glass instrument is used in the aforementioned experimental equipment.

[0032] The technical solution of the above embodiment calls a camera to capture video images of the glass instrument in real time, identifies the liquid level change image and its corresponding volume reading from the video image based on optical coding marks, and corrects it to obtain the actual reading. Based on the actual reading, real-time reading information is generated and displayed at the liquid level position. This technical solution can automatically and accurately identify the concave surface of the liquid and calibrate the reading in chemical experiment teaching, which can help students read the correct value without teachers having to repeatedly calibrate the glass instrument reading. It meets the needs of laboratory teaching efficiency and operational standardization, and improves the teaching efficiency and effectiveness of titration experiments.

[0033] Additional aspects and advantages of this application will be set forth in part in the description which follows, and will become apparent from the description or may be learned by practice of this application. Attached Figure Description

[0034] The above and / or additional aspects and advantages of this application will become apparent and readily understood from the following description of the embodiments taken in conjunction with the accompanying drawings, wherein:

[0035] Figure 1 This is a block diagram of an example terminal device;

[0036] Figure 2 This is a schematic diagram of an example experimental instrument and equipment;

[0037] Figure 3 This is a schematic diagram illustrating an example of the process for determining a volume reading;

[0038] Figure 4 This is a schematic diagram of an example glass instrument;

[0039] Figure 5 This is a schematic diagram of an example optical path model;

[0040] Figure 6 This is a schematic diagram illustrating real-time reading information as an example;

[0041] Figure 7 This is a schematic diagram of an example titration experiment. Detailed Implementation

[0042] The embodiments of this application are described in detail below. Examples of these embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain this application, and should not be construed as limiting this application.

[0043] Those skilled in the art will understand that, unless otherwise stated, the singular forms “a,” “an,” “the,” and “the” used herein may also include the plural forms. It should be further understood that the word “comprising” as used in this application’s specification means the presence of the stated feature, integer, step, or operation, but does not preclude the presence or addition of one or more other features, integers, steps, or operations.

[0044] This application addresses a deficiency in reading calibration during teaching experiments using glass instruments for measuring liquid volume. In one embodiment, the experimental instrument comprises a glass instrument and a terminal device: the glass instrument, used for measuring liquid volume, is equipped with an optically coded mark; the terminal device includes a camera, one or more processors, a memory, and one or more applications stored in the memory; for example,... Figure 1 As shown, Figure 1 This is a block diagram of an example terminal device. The example terminal device includes a processor, memory, communication interface, display screen, and input device connected via a system bus. The processor provides computing and control capabilities; the memory includes non-volatile storage media and internal memory; the non-volatile storage media stores the operating system and computer programs; the internal memory provides an environment for the operation of the operating system and computer programs stored in the non-volatile storage media. The communication interface is used for wired or wireless communication with external terminals. Wireless communication can be achieved through Wi-Fi, mobile cellular networks, NFC (Near Field Communication), or other technologies. The display screen can be an LCD screen or an e-ink screen. The input device can be a touch layer covering the display screen, buttons, a trackball, or a touchpad on the terminal device's casing, or an external keyboard, touchpad, or mouse. It should be noted that... Figure 1 The structural frame shown is merely a block diagram of a portion of the structure related to the present application and does not constitute a limitation on the terminal device to which the present application is applied. Specific terminal devices may include more or fewer components than those shown in the figure, or combine certain components, or have different component arrangements.

[0045] In this embodiment, one or more applications of the terminal device are configured to be executed by the one or more processors as follows: calling a camera to capture video images of the glass instrument in real time; identifying the liquid level change image and its corresponding volume reading from the video image based on the optical coding mark; correcting the volume reading to obtain the actual reading; generating real-time reading information based on the actual reading; and displaying the real-time reading information at the liquid level position based on the optical coding mark.

[0046] Specifically, the terminal device can capture real-time video images of the experimental site, including images of liquid level changes inside the glassware. Based on the printed optical coding marks, the area where the glassware is located in the video image can be identified. Then, image processing is used to identify the liquid level position from the liquid level change image. Combined with the volume scale value on the glassware, the liquid level position is determined, and the volume reading corresponding to the lowest point of the concave surface of the liquid level is determined. Then, the required real-time reading information is generated based on the actual reading. Combined with the printed optical coding marks on the glassware, the real-time reading information to be displayed is placed at the liquid level position.

[0047] For example, to avoid interfering with routine experiments, optical coding marks can be printed using ultraviolet fluorescent ink. The specific printing shape and area depend on the usage requirements. Using ultraviolet fluorescent ink, glassware can be quickly and accurately identified from liquid level change images in laboratory environments with special lighting requirements. In addition, experimental instruments and equipment may also include some other related supporting equipment. The terminal device may be a smartphone, a computer device connected to a camera, or a wearable device (such as AR glasses, VR devices, etc.). One or more applications are installed on the terminal device in the form of an App.

[0048] In this embodiment, a graduated cylinder will be used as an example for description. Figure 2 As shown, Figure 2 This is a schematic diagram of an example experimental apparatus. The glass instrument in the diagram is a graduated cylinder, and optical coding marks (not shown in the diagram) are printed on the surface of the graduated cylinder. When reading the graduated cylinder, the camera simulates the observation position of the human eye. At this time, the line of sight is required to be tangent to the lowest point of the concave surface of the liquid. The scale of the horizontal line that coincides with the lowest point of the concave surface of the liquid is the volume reading.

[0049] For example, when displaying real-time reading information, if a wearable device, such as VR glasses, is used, the real-time reading information can be superimposed on the optically encoded mark at the liquid surface position in real time to achieve a follow-up display effect, and the operator can see the volume reading by looking at the glass instrument; if a smartphone is used, the operator can point the camera at the liquid surface position, and at this time the image with the volume reading can be displayed on the phone screen.

[0050] The solution described in the above embodiment enables teachers to automatically read liquid volume using glass instruments during teaching. It also assists students in reading the volume and observing real-time data changes. Teachers no longer need to constantly calibrate the glass instruments, reducing wasted teaching time. The teaching process can be standardized, improving teaching efficiency and effectiveness.

[0051] In one embodiment, when the terminal device determines a volume reading, the one or more applications are configured to be executed by the one or more processors as follows: acquiring each frame of a video image showing changes in the liquid level; inputting the liquid level change images into a pre-trained deep learning model to determine the liquid level position; performing edge detection on the liquid level position to identify the concave line of the liquid level; and determining the volume reading based on the lowest point of the concave line of the liquid level and the scale lines of the glass instrument.

[0052] Specifically, such as Figure 3 As shown, Figure 3 This is a schematic diagram illustrating an example of the process for determining a volume reading. A convolutional neural network, based on a pre-trained deep learning model, can be used to identify the position of the liquid surface in an image of liquid level changes. After identifying the position of the liquid surface in the image of liquid level changes, an edge detection algorithm is used to identify the concave line of the liquid surface from the image. The corresponding volume reading can be determined based on the horizontal correspondence between the lowest point of the concave line of the liquid surface and the scale line of the glass instrument.

[0053] In one embodiment, considering that when observing readings of glassware in chemical experiments, the operator's line of sight must be tangent to the lowest point of the concave surface of the liquid, and the refractive effect of the glassware must be taken into account, finding the accurate observation position and correcting for refractive index are crucial for accurate readings in chemical experiments. Training students to find the accurate observation position and perform refractive index correction is an important aspect of experimental teaching. In conventional experimental teaching, teachers are required to impart their experience to students. This model consumes a significant amount of teaching time, severely impacting teaching efficiency and preventing the standardization of teaching methods.

[0054] Accordingly, in the technical solution of the terminal device of this application, when the terminal device acquires the actual reading, the one or more applications are configured to execute the following method by the one or more processors: calculating the camera pose parameters of the camera based on the liquid level change image, the camera parameters of the camera, and the instrument parameters of the glass instrument; and correcting the volume reading based on the refractive index parameters of the glass instrument tube wall and the camera pose parameters to obtain the actual reading.

[0055] Specifically, when using a camera to capture video images of glass instruments, the camera is positioned at a certain distance from the glass instrument and at a certain shooting angle. This angle generally refers to the angle between the central axis of the camera and the horizontal line between the center point of the camera and the burette. At this time, the image of the glass instrument is obtained based on the liquid level change image. The specific size of the object can be obtained through the instrument parameters of the glass instrument. Using the image of the glass instrument and its size, combined with the camera parameters, the camera pose parameters of the camera can be calculated, including the relative position between the camera and the glass instrument and the shooting angle. Since the glass instruments are mainly made of glass, their tube walls have a refractive effect, and the readings of the glass instruments will be affected by the refractive index of the tube walls.

[0056] In the technical solution of this application, the camera pose parameters of the camera are first calculated, and then the refractive index parameters of the glass instrument tube wall are determined according to the glass instrument material. Combining the camera pose parameters and refractive index parameters, the identified volume reading is visually corrected and refractive index compensated to obtain the actual reading, thereby obtaining accurate reading results, providing operators with intuitive reading references, and improving the experimental teaching effect.

[0057] In this embodiment, when calculating the camera pose parameters of the camera, the image of the glass instrument can be identified from the liquid level change image; the camera parameters of the camera and the instrument parameters of the glass instrument can be obtained; the coordinate parameters of the reference point on the glass instrument image can be determined according to the instrument parameters; and the camera pose parameters of the camera can be calculated according to the coordinate parameters and the camera parameters.

[0058] Furthermore, the first coordinates of each reference point on the coordinate system can be determined based on the instrument parameters; the rotation matrix and translation vector of the camera can be calculated based on the first coordinates and camera parameters; and the relative position and shooting angle between the camera and the glass instrument can be determined based on the rotation matrix and translation vector.

[0059] For example, the glass instrument image includes all or part of the glass instrument image. The glass instrument image is identified from the liquid level change image; this requires identifying all or part of the glass instrument image and extracting it. Camera parameters may include focal length, principal point coordinates, and distortion coefficients. Instrument parameters include the dimensions of the glass instrument, such as outer diameter, length, and capacity. Since camera parameters affect the imaging geometry, for example, smartphones and wearable devices can directly obtain camera parameters, including focal length, principal point coordinates, distortion coefficients, and sensor information. The actual dimensions of the glass instrument can be used as a reference for calculating the camera pose parameters. A three-dimensional coordinate system (such as the world coordinate system) can be used. Reference points are selected on the glass instrument, and the coordinate parameters determined by these reference points, combined with the camera parameters and the pixel size of the reference points on the glass instrument image, can be used to calculate the camera pose parameters.

[0060] In this embodiment, when calculating the camera pose parameters, a segment of the glass instrument image showing the liquid surface changes can be captured at the liquid surface location, and then the four vertices of the glass instrument image can be selected as reference points; for example... Figure 4 As shown, Figure 4 This is a schematic diagram of an example glass instrument. As shown, four reference points, p1, p2, p3, and p4, are selected. After selecting the reference points, the coordinate parameters corresponding to each reference point are determined based on the instrument parameters. The inner and outer diameters of the glass instrument are known. The glass instrument is always placed vertically during use. By combining the volume scale values ​​on the glass instrument with the inner diameter, the length corresponding to each scale mark can be determined. The width value can be determined based on the outer diameter of the glass instrument, thus allowing the determination of the coordinate parameters corresponding to each reference point. Figure 4 In the spatial coordinate system, the relative coordinates of the four reference points p1, p2, p3, and p4 are known, therefore the actual coordinate parameters of each reference point can be calculated; for example... Figure 4 As shown in the left figure, a section of the glass instrument defined by the four reference points p1, p2, p3, and p4 is rectangular. However, due to the rotation of the image of the glass instrument captured by the camera, the glass instrument formed by the four reference points is an irregular rectangle p1', p2', p3', and p4', as shown in the figure. Figure 4 As shown in the right figure, p1', p2', p3', and p4' are trapezoids. Therefore, by solving the correspondence between 3D and 2D points, such as the PnP (Perspective-n-Point) algorithm, and combining the first coordinates of the known reference point on the glass instrument with the camera parameters, the rotation matrix and translation vector of the camera can be calculated. Then, the distance between the camera and the glass instrument can be determined based on the translation vector, thereby determining the relative position. The rotation matrix can be converted into Euler angles to obtain the shooting angle between the camera and the glass instrument.

[0061] For example, when the camera is facing the glass instrument, the actual dimensions of the rectangle p1p2p3p4 are known, with one side length H. Given its pixel width in the image as h, and the camera's focal length f (in pixels), the distance between the camera and the glass instrument is D = (H × f) / h. At a certain shooting angle α, the relationship between the length H and the pixel width h is D = (H × f × cosα) / h. The camera's central axis forms an angle α with the horizontal line of sight of the burette. The rectangle p1p2p3p4 is a trapezoid in the image. By establishing the ratio and angle of the trapezoid's upper and lower sides, a corresponding geometric model can be built. The tilt angle and distance of the camera relative to the midpoint of the trapezoid can then be calculated. Based on the tilt angle and distance, the shooting angle and relative position of the camera relative to the glass instrument can be obtained.

[0062] When correcting the volume reading to obtain the actual reading, the second coordinate of the liquid surface position on the coordinate system can be obtained; the third coordinate of the camera on the coordinate system can be obtained according to the relative position; the refractive index parameter of the glass instrument tube wall can be determined according to the material used by the glass instrument; an optical path model can be constructed according to the shooting angle, the second coordinate, the third coordinate and the refractive index parameter, and the actual reading of the glass instrument can be obtained by compensating the tube wall refractive index of the volume reading according to the optical path model.

[0063] Specifically, the second coordinate P2 of the lowest point of the concave surface of the liquid can be determined based on the burette graduations. The third coordinate P3 of the camera can be determined based on the relative position between the camera and the burette. Then, an optical path model is constructed based on the shooting angle α, the second coordinate P2, the third coordinate P3, and the refractive index parameter. This model represents the optical path of light from the bottom of the concave surface of the liquid to the camera. Figure 5 As shown, Figure 5 This is a schematic diagram of an example optical path model. Based on this optical path model, the volume reading can be compensated for by the refractive index of the tube wall to obtain the actual reading of the burette.

[0064] In one embodiment, considering that glassware is usually placed vertically during chemical experiments, and that the operator is required to look directly at the concave line of the liquid surface and keep the line of sight tangent to the concave surface when taking the correct reading, the operator also needs to master the method of looking directly at the concave line of the liquid surface in actual operation. Accordingly, the technical solution of this application can also be a technical solution for calibrating the observation position.

[0065] The line-of-sight deviation angle is calculated based on the first coordinate of the reference point in the glass instrument image and the position of the concave line of the liquid surface in the burette image. The adjustment direction of the camera is then calculated based on this deviation angle, and corresponding prompts are generated and displayed. Figure 4 , Figure 5In the example, reference points p1, p2, p3, and p4 are rectangular, and the camera position simulates the observation position of the human eye. At this point, the human eye is perpendicular to the glass instrument. When the line of sight is tangent to the concave surface of the liquid, the camera's center line is directly aligned with the concave point, and the camera's central axis is directly aligned with the concave line. This is the most accurate observation position. However, due to inaccurate shooting angles, such as... Figure 4 As shown in the right figure, p1', p2', p3', and p4' form a trapezoid, where p1' and p2' are the shorter sides and p3' and p4' are the longer sides. This indicates that the line of sight is from top to bottom. Therefore, by calculating the adjustment amount corresponding to when the four reference points p1', p2', p3', and p4' in the glass instrument image form a regular rectangle, we can obtain the deviation between the operator's current observation position and the most accurate observation position. This generates adjustment prompts (such as up, down, left, right, etc.) for the operator to adjust the observation position and angle. For example, using AR glasses, the operator can adjust the observation position by looking up or turning their head.

[0066] As in the above embodiment, the camera's shooting position is used to simulate the human eye's observation position. The image of the glass instrument is used to detect whether the line of sight is tangent to the concave line of the liquid surface. This can train students in teaching how to find the correct observation position and avoid looking down or up when observing the readings of the glass instrument.

[0067] In one embodiment, when the experimental instrument and terminal device of this application displays real-time reading information, the one or more applications are configured to execute the following method by the one or more processors: generating corresponding real-time reading information based on the actual reading of each frame of liquid level change image; identifying the optically encoded mark using tracking technology, and determining the target display position of the real-time reading information based on the optically encoded mark; and displaying the real-time reading information according to the target display position.

[0068] Specifically, for each frame of liquid level change image, after correction, the actual reading is obtained, and corresponding real-time reading information is generated. For example, accurate reading values ​​can be generated directly, as well as the error value between the currently observed volume reading and the actual reading. Furthermore, other information related to the reading can be generated. AR motion tracking technology can be used to identify the optical coding marks printed on the glass instrument in real time. Combined with the identified liquid level position, the target display position for the real-time reading information is determined based on the optical coding marks. When using a smartphone, a display interface can be generated based on the liquid level change image. The real-time reading information is then overlaid onto the display interface based on the target display position. When using wearable devices, such as AR glasses, the real-time reading information can be projected onto the target display position. Users can observe the glass instrument through AR glasses and obtain accurate readings and other reading-related information in real time.

[0069] like Figure 6 As shown, Figure 6 This is a schematic diagram of real-time reading information as an example. If the volume reading is 3.80ml based on direct observation, the actual reading after calibration is 3.85ml, as shown in the figure. This is the true reading with an error of 0.05ml. The concave liquid level can be automatically identified by a smartphone or wearable device to help students read the liquid correctly.

[0070] As in the technical solution of the above embodiment, the accurate actual reading is obtained by correcting the volume reading obtained intuitively, and the error between the readings is presented. This allows students to better grasp the error of the reading in the titration experiment, so that students can continuously master the method of accurate reading and avoid errors in the reading process.

[0071] In summary, the solutions of the above embodiments allow students to obtain accurate readings of glass instruments in real time using smartphones or wearable devices during chemical experiments, thus avoiding reading deviations. In experimental teaching, teachers no longer need to repeatedly guide students to correct reading methods and calibrate glass instrument readings. The software recognition enables standardized reading calibration, allowing students to obtain accurate readings in real time, thereby greatly improving the efficiency and effectiveness of experimental teaching.

[0072] The following describes several embodiments of this application in titration experiments; the graduated cylinder in the aforementioned embodiments can also be replaced with a burette, and optical coding marks can also be printed on the burette to enable reading and identification during the titration experiment.

[0073] like Figure 7 As shown, Figure 7 This is a schematic diagram of an example titration experiment. Since reading the liquid level is one of the important parts of the titration experiment, different teachers have different experience, so parallax errors can occur. The liquid level reading of the glass instrument needs to be observed by the naked eye at the lowest point of the concave surface of the liquid. It is affected by the observation angle (such as looking down or looking up) and the ambient light, resulting in a large range of errors. In teaching, teachers need to repeatedly guide students to correct the reading method, which takes up a lot of time, resulting in low teaching efficiency and difficulty in achieving standardized teaching, thus making it difficult to guarantee the quality of teaching.

[0074] In one embodiment, the terminal device can obtain the corresponding solution parameters based on the actual readings identified in each frame of the liquid level change image. A titration curve is then fitted onto the titration curve graph based on the actual readings and their corresponding solution parameters, and dynamically displayed on the display interface. The titration curve is obtained by fitting the coordinate points of the solution parameters calculated for each frame. For example, a smartphone or wearable device can automatically calculate the titration curve and endpoint determination logic and display them dynamically. This can assist students in deeply understanding the titration process during the titration experiment, enhance the training effect of the experiment, and improve the teaching support effect.

[0075] For example, when dynamically displaying the titration curve, a camera can be used to capture real-time images of the potentiometric titrator's readings. The corresponding readings can be identified from these images, and when the reading reaches the titration endpoint, a titration endpoint prompt is generated. Both the reading image and the titration endpoint prompt are then displayed in real-time. Specifically, during the titration process, a camera is used to capture real-time images of the potentiometric titrator's readings to obtain the corresponding readings. When the reading is close to the endpoint, the reading image and the titration endpoint prompt are displayed in real-time, thereby enhancing students' training in the titration experiment process.

[0076] For example, when dynamically displaying the titration curve, a camera can be used to capture real-time images of the sample solution inside the conical flask, and the color of the sample solution can be identified from the image. When a color change is detected in the sample solution with added indicator, a titration endpoint prompt is generated and displayed in real-time at the location of the conical flask. Specifically, during the titration process, the measurement point or endpoint of the titration curve can be calculated based on the color change (indicator color). By displaying relevant prompts in real-time based on the color of the sample solution, students can be reminded of each key step in the titration experiment, thereby improving teaching efficiency and enhancing the effectiveness of titration experiment teaching and training.

[0077] In this embodiment, when using the terminal device, students can install the corresponding App tool on the terminal device. During the titration experiment, the terminal device's camera can be used to take real-time pictures of the glass instruments, and the terminal device can display the observed glass instrument readings in real time, as well as the correct readings. This can train students to read accurately, and the entire reading process can be standardized, which reduces the workload of teachers, avoids the influence of errors, and improves teaching effectiveness.

[0078] The above description is only a partial embodiment of this application. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the principle of this application, and these improvements and modifications should also be considered within the scope of protection of this application.

Claims

1. An experimental instrument, characterized in that, include: A glass instrument for measuring liquid volume, wherein the glass instrument is provided with optically coded markings; A terminal device, the terminal device comprising: a camera, one or more processors, a memory, and one or more applications stored in the memory; The one or more applications are configured to execute the following methods by the one or more processors: The camera captures video images of the glass instrument in real time, and the liquid level change image and its corresponding volume reading are identified from the video image based on the optical coding mark; The volume reading is corrected to obtain the actual reading, and real-time reading information is generated based on the actual reading. Specifically, this includes: identifying the glass instrument image from the liquid level change image; acquiring the camera parameters and the instrument parameters of the glass instrument; selecting multiple reference points on the glass instrument image; determining the first coordinates of each reference point in the coordinate system based on the instrument parameters; calculating the rotation matrix and translation vector of the camera based on the first coordinates and camera parameters; determining the relative position and shooting angle between the camera and the glass instrument based on the rotation matrix and translation vector; acquiring the second coordinates of the liquid level position in the coordinate system; acquiring the third coordinates of the camera in the coordinate system based on the relative position; determining the refractive index parameter of the glass instrument tube wall based on the material used in the glass instrument; constructing an optical path model based on the shooting angle, the second coordinates, the third coordinates, and the refractive index parameter; and compensating the volume reading for tube wall refractive index based on the optical path model to obtain the actual reading of the glass instrument. Displaying the real-time reading information at the liquid surface position according to the optically encoded mark specifically includes: generating corresponding real-time reading information based on the actual reading of each frame of liquid surface change image; identifying the optically encoded mark using tracking technology and determining the target display position of the real-time reading information based on the optically encoded mark; and displaying the real-time reading information according to the target display position. as well as The viewing deviation angle is calculated based on the first coordinate of the reference point in the glass instrument image and the position of the concave line of the liquid surface in the glass instrument image. The adjustment direction of the camera is calculated based on the deviation angle, and corresponding prompt information is generated and displayed.

2. The experimental apparatus according to claim 1, characterized in that, The terminal device is a smartphone, a computer device connected to a camera, or a wearable device; wherein, the one or more applications are installed on the terminal device in the form of an App.

3. The experimental apparatus according to claim 1, characterized in that, The one or more applications are configured to execute the following methods by the one or more processors: Acquire each frame of the video image showing changes in the liquid surface, input the liquid surface change images into a pre-trained deep learning model to identify the liquid surface position; perform edge detection on the liquid surface position to identify the concave line of the liquid surface; The volume reading is determined based on the lowest point of the concave surface of the liquid and the graduation lines of the glass instrument.

4. A glass instrument for measuring the volume of a liquid, characterized in that, The glass instrument has an optical coding mark printed on its surface; the glass instrument is used in the experimental apparatus according to any one of claims 1-3.

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