Glass instrument and experimental instrument equipment for measuring liquid volume

Abstract

The invention relates to a glass instrument and experimental instrument equipment for measuring the volume of liquid. The experimental instrument equipment comprises a glass instrument which is used for measuring the volume of liquid and is provided with an optical coding mark; the terminal equipment 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 be executed by the one or more processors according to the following method: calling the camera to shoot a video image of the glass instrument in real time, and identifying a liquid level change image of the liquid and a corresponding volume reading from the video image according to the optical coding mark; correcting the volume reading to obtain an actual reading, generating real-time reading information according to the actual reading, and displaying the real-time reading information at the liquid level position according to the optical coding mark; according to the technical scheme, the teaching efficiency and effect of the titration experiment are improved.

Description

Technical Field

[0001] The present application relates to the technical field of experimental instruments and equipment, and in particular to a glass instrument and experimental instrument equipment for measuring liquid volume. Background Art

[0002] In chemical experiments, glass instruments are used to measure the volume of liquid. These glass instruments include measuring cylinders, measuring cups, volumetric flasks, burettes, pipettes, etc. These instruments have their own characteristics and are suitable for different experimental needs.

[0003] In a laboratory environment, accurately reading the volume of liquids is crucial for chemical analysis. Readings from these glass instruments require precise positioning of the observer, accurate identification of the liquid level, and consideration of the effects of glass refraction. Therefore, extensive training is required to improve operator proficiency.

[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 measurement readings, which takes up a lot of teaching time. In addition, this model makes it difficult to achieve standardized teaching, which seriously affects teaching efficiency and effectiveness. Summary of the Invention

[0005] In order to solve one of the above-mentioned defects, the present application provides a glass instrument and experimental instrument equipment for measuring liquid volume, so as to improve the efficiency and effect of reading teaching using glass instruments in chemical experiments.

[0006] An experimental instrument comprises:

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

[0008] A 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 execute the following method by the one or more processors: calling a camera to capture a video image of a glass instrument in real time, identifying an image of liquid level changes and its corresponding volume reading from the video image based on the optical coding mark; correcting the volume reading to obtain an 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.

[0010] In one embodiment, the terminal device is a smart phone, 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 method by the one or more processors:

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

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

[0014] The liquid level change image of each frame of the video image is obtained, and the liquid level change image is input into a pre-trained deep learning model to obtain the liquid level position; the edge detection of the liquid level position is performed to identify the liquid surface concave line; and the volume reading is determined based on the lowest point of the liquid surface concave line and the scale line of the glass instrument.

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

[0016] Identify a glass instrument image from the liquid level change image; obtain camera parameters of a camera and instrument parameters of the glass instrument; determine coordinate parameters of a reference point on the glass instrument image according to the instrument parameters, and calculate camera pose parameters of the camera 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 execute the following method by the one or more processors:

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

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

[0020] Obtain a second coordinate of the liquid level position in the coordinate system; obtain a third coordinate of the camera in the coordinate system based on the relative position; determine a 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 compensate the volume reading for the tube wall refractive index based on the optical path model to obtain an actual reading of the glass instrument.

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

[0022] The sight deviation angle is calculated according to the first coordinate of the reference point of the glass instrument image and the position of the liquid surface concave line in the burette image, the adjustment direction of the camera is calculated according to the deviation angle, and corresponding prompt information is generated for display.

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

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

[0025] In one embodiment, the glassware is a burette; and the one or more applications are configured to execute the following method by the one or more processors:

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

[0027] In one embodiment, the glassware is a burette; and the one or more applications are configured to execute the following method by the one or more processors:

[0028] A camera is used to capture the reading image of the potentiometric titrator in real time, and the corresponding reading is identified from the reading image; when the reading reaches the titration end point, a titration end point prompt is generated, and the reading image and the titration end point prompt are displayed in real time.

[0029] In one embodiment, the glassware is a burette; and the one or more applications are configured to execute the following method by the one or more processors:

[0030] A camera is used to capture an image of the sample solution in the conical flask in real time, and the color of the sample solution is identified from the sample solution image. When a color change is detected in the sample solution to which the indicator is added, a titration end point prompt is generated and placed at the position of the conical flask for real-time display.

[0031] A glass instrument for measuring liquid volume, with optical coding marks printed on the surface of the glass instrument; the glass instrument is used for the experimental instrument equipment.

[0032] The technical solution of the above embodiment calls on a camera to capture a video image of the glass instrument in real time, identifies the liquid level change image and its corresponding volume reading from the video image based on the optical coding mark and corrects it to obtain the actual reading, generates real-time reading information based on the actual reading, and displays the real-time reading information at the liquid level position; this technical solution can automatically and accurately identify the concave surface of the liquid surface and calibrate the reading in chemical experiment teaching, which can assist students in reading correctly without the need for teachers to repeatedly calibrate the glass instrument readings, meets the requirements of laboratory teaching efficiency and operational standardization, and improves the teaching efficiency and effect of titration experiments.

[0033] Additional aspects and advantages of the present application will be given in part in the following description, which will become apparent from the following description, or will be learned through practice of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

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

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

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

[0037] Figure 3 is a schematic diagram of an example process for determining volume readings;

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

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

[0040] Figure 6 This is a sample diagram of real-time reading information;

[0041] Figure 7 is a schematic diagram of an example titration experiment. DETAILED DESCRIPTION

[0042] The following describes in detail embodiments of the present application, examples of which are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present application, and are not to be construed as limiting the present 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 plural forms. It should be further understood that the term "comprising" used in the specification of this application refers to the presence of the stated features, integers, steps, and operations, but does not preclude the presence or addition of one or more other features, integers, steps, and operations.

[0044] The present application is directed to an experimental instrument device for addressing defects in reading calibration in teaching experiments using glass instruments for measuring liquid volume. In one embodiment, the experimental instrument device of the present application includes a glass instrument and a terminal device: the glass instrument is used to measure liquid volume and is provided with an optical coding mark; the terminal device includes: a camera, one or more processors, a memory, and one or more application programs stored in the memory; for example, Figure 1 As shown, Figure 1 This is a structural block diagram of an example terminal device, which includes a processor, memory, communication interface, display screen and input device connected via a system bus. Among them, the processor of the terminal device is used to provide computing and control capabilities; the memory of the terminal device includes a non-volatile storage medium and an internal memory; the non-volatile storage medium stores an operating system and a computer program; the internal memory provides an environment for the operation of the operating system and computer program in the non-volatile storage medium. The communication interface of the terminal device is used to communicate with an external terminal in a wired or wireless manner, and the wireless manner can be achieved through WIFI, mobile cellular network, NFC (near field communication) or other technologies; the display screen of the terminal device can be a liquid crystal display or an electronic ink display screen, and the input device of the terminal device can be a touch layer covering the display screen, or a button, trackball or touchpad provided on the terminal device housing, or an external keyboard, touchpad or mouse, etc. It should be noted that, Figure 1 The structural frame shown in the figure is only a block diagram of a part of the structure related to the scheme of the present application, and does not constitute a limitation on the terminal device to which the scheme of the present application is applied. The specific terminal device may include more or fewer components than shown in the figure, or combine certain components, or have a different component arrangement.

[0045] In this embodiment, one or more applications of the terminal device are configured to execute the following method by the one or more processors: calling the camera to capture a video image 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 an 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 be used to capture real-time video images of the experimental site. The video images include images of the liquid level changes of the liquid in the glass instrument. The area where the glass instrument is located in the video image can be identified based on the printed optical coding mark. Image processing is then used to identify the liquid level position from the liquid level change image. Combined with the volume scale value on the glass instrument, the liquid level position is determined to determine the volume reading corresponding to the lowest point of the concave surface of the liquid surface. The required real-time reading information is then generated based on the actual reading. Combined with the optical coding mark printed on the glass instrument, the real-time reading information to be displayed is placed at the liquid level position for display.

[0047] For example, in order to avoid interfering with routine experiments, optical coding marks can be printed with ultraviolet fluorescent ink. The specific printing shape and area depend on the usage requirements. Ultraviolet fluorescent ink can be used to quickly and accurately identify glassware from the liquid surface change image in a laboratory environment with special lighting requirements. In addition, experimental instruments and equipment can also include some other related supporting equipment; the terminal device can be a smart phone, a computer device connected to a camera, or a wearable device (such as AR glasses, VR equipment, etc.); one or more applications are installed on the terminal device in the form of an App.

[0048] In the embodiment of the present application, the description will be mainly based on the graduated cylinder. Figure 2 As shown, Figure 2 This is a schematic diagram of an example experimental instrument. The glass instrument in the figure is a measuring cylinder with an optical coding mark printed on the surface of the measuring cylinder (not shown in the figure). When reading the measuring cylinder, the camera is equivalent to simulating 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 surface. The scale of the horizontal line coinciding with the lowest point of the concave surface of the liquid surface 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 and displayed at the liquid surface position in real time following the optical coding mark, achieving a follow-up display effect, and the operator can display the volume reading by looking at the glass instrument; if a smart phone is used, the operator can aim the camera at the liquid surface position, and then an image with the volume reading can be displayed on the phone screen.

[0050] As in the above-mentioned embodiment, when teaching the measurement of liquid volume using a glass instrument, teachers can assist students in automatically reading the readings, and can assist students in reading the readings and observing images of real-time data changes in the experiment. Teachers no longer need to constantly calibrate the glass instrument readings, which reduces the waste of teaching time, and the teaching process can be standardized, thereby improving teaching efficiency and effectiveness.

[0051] In one embodiment, when the terminal device determines the volume reading, the one or more applications are configured to execute the following method by the one or more processors: obtaining a liquid level change image of each frame of the video image, inputting the liquid level change image into a pre-trained deep learning model to obtain the liquid level position; performing edge detection on the liquid level position to identify the liquid surface concave line; and determining the volume reading based on the lowest point of the liquid surface concave line and the scale line of the glass instrument.

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

[0053] In one embodiment, when observing glassware readings 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 considered. Finding the correct observation position and compensating for the refractive index are key to accurate readings in chemical experiments. Training students in finding the correct observation position and compensating for the refractive index is a key component of experimental teaching. Conventional experimental teaching requires teachers to rely on their own experience to impart knowledge to students. This model consumes a significant amount of teaching time, severely impacts teaching efficiency, and prevents standardized teaching methods.

[0054] Based on this, further, in the technical solution of the terminal device of the present application, when the terminal device obtains the actual reading, the one or more applications are configured to execute the following method by the one or more processors: calculating the camera posture 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; correcting the volume reading according to the refractive index parameters of the glass instrument tube wall and the camera posture parameters to obtain the actual reading.

[0055] Specifically, when using a camera to capture a video image of a glass instrument, the camera is at a certain distance from the glass instrument and at a certain shooting angle. The angle here generally refers to the angle between the central axis direction of the camera and the horizontal line between the center point of the camera and the burette. At this time, the glass instrument image is obtained based on the liquid level change image, and its specific object size can be obtained through the instrument parameters of the glass instrument. The camera posture parameters of the camera, including the relative position between the camera and the glass instrument and the shooting angle, can be calculated using the glass instrument image and its object size, combined with the camera parameters of the camera. Since the glass instrument is mainly made of glass, its tube wall has a refractive effect. When reading the glass instrument, it will be affected by the refractive index of the tube wall.

[0056] In the technical solution of the present 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 material of the glass instrument. Combined with the camera pose parameters and the refractive index parameters of the camera, the identified volume reading is corrected for visual errors and compensated for the refractive index to obtain the actual reading, thereby obtaining an accurate reading result, providing the operator with an intuitive reading reference, and improving the experimental teaching effect.

[0057] In this embodiment, when calculating the camera pose parameters of the camera, a glass instrument image can be 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.

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

[0059] Exemplarily, the glassware image includes the entire or partial image of the glassware, and the glassware image is identified from the liquid level change image. What is needed here is to identify the entire or partial image of the glassware, identify the glassware image and cut it out; camera parameters may include focal length, principal point coordinates and distortion coefficient; instrument parameters include the dimensions of the glassware, such as outer diameter, length, and capacity, etc. Since the camera parameters of the camera affect the imaging geometry, for example, smartphones and wearable devices can directly obtain the camera parameters of the camera, including focal length, principal point coordinates, distortion coefficient, and sensor information, etc.; the actual dimensions of the glassware can be used as a reference for calculating the camera pose parameters of the camera; a three-dimensional coordinate system (such as a world coordinate system) can be used; reference points are selected on the glassware, and the coordinate parameters determined by these reference points are combined with the camera parameters and the pixel size of the reference points on the glassware image to calculate the camera pose parameters.

[0060] In this embodiment, when calculating the camera pose parameters of the camera, a glass instrument image of a liquid surface change image can be intercepted at the liquid surface position, and then four vertices of the glass instrument image are selected as reference points; Figure 4 As shown, Figure 4 This is a schematic diagram of an example glass instrument image. In the figure, four reference points, p1, p2, p3, and p4, are selected. After the reference points are selected, the coordinate parameters corresponding to each reference point are determined according to the instrument parameters. The inner diameter and outer diameter of the glass instrument are known. The glass instrument is placed vertically when used. The length corresponding to each scale can be determined by the volume scale value on the glass instrument combined with the inner diameter size. The width value can be determined according to the outer diameter size of the glass instrument, thereby determining 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, so the actual coordinate parameters of each reference point can be calculated; Figure 4 As shown in the left figure, a glass instrument determined by four reference points p1, p2, p3, and p4 is a rectangle. Since the image of the glass instrument taken by the camera is rotated at a certain angle, the glass instrument formed by the four reference points is an irregular rectangle p1', p2', p3', and p4'. Figure 4 As shown in the right figure, p1', p2', p3', and p4' are trapezoidal. Therefore, by solving the correspondence method from 3D to 2D points, such as the PnP (Perspective-n-Point) algorithm, the rotation matrix and translation vector of the camera can be calculated in combination with the first coordinate of the known reference point on the glass instrument and the camera parameters. The distance between the camera and the glass instrument is then determined based on the translation vector to determine 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 glassware, the actual dimensions of the rectangle p1p2p3p4 are known. One of its sides is H, and based on the pixel width h occupied by the rectangle in the image and the camera's focal length f (in pixels), the distance between the camera and the glassware 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 is at an angle α with the burette's horizontal line of sight. The rectangle p1p2p3p4 appears as a trapezoid in the image. By establishing a corresponding geometric model based on the ratio and angle of the trapezoid's upper and lower sides, the camera's tilt angle and distance relative to the trapezoid's midpoint can be calculated. Based on the tilt angle and distance, the camera's shooting angle and relative position relative to the glassware can be determined.

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

[0063] Specifically, the second coordinate P2 of the lowest point of the concave surface of the liquid surface in the coordinate system can be determined according to the scale value of the burette, and the third coordinate P3 of the camera in the coordinate system can be determined according to the relative position between the camera and the burette. Thereafter, the optical path model is constructed according to the shooting angle α, the second coordinate P2, the third coordinate P3 and the refractive index parameter, that is, the optical path model of the light from the bottom of the concave surface of the liquid surface to the camera, as shown in FIG. Figure 5 As shown, Figure 5 This is a schematic diagram of an optical path model. Based on this optical path model, the volume reading can be compensated for 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 correct reading requires the operator to look directly at the concave line of the liquid surface, and keep the line of sight tangent to the concave surface of the liquid surface, in actual operation, the operator also needs to master how to look directly at the concave line of the liquid surface. Based on this, the technical solution of the present application can also further calibrate the observation position.

[0065] The sight deviation angle is calculated according to the first coordinate of the reference point of the glass instrument image and the position of the concave line of the liquid surface in the burette image, and the adjustment direction of the camera is calculated according to the deviation angle and corresponding prompt information is generated for display; 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 time, the human eye is perpendicular to the glass instrument. When the line of sight is tangent to the concave surface of the liquid surface, the center line of the camera is facing the concave point of the liquid surface, and the central axis of the camera is facing the concave line of the liquid surface. At this time, the observation position is the most accurate observation position. If the shooting angle is inaccurate, such as Figure 4 As shown in the right figure, p1', p2', p3', and p4' are trapezoids, where p1'p2' are short sides and p3'p4' are long sides; this indicates that the line of sight is at a downward angle at this time. Therefore, the corresponding adjustment amount when the four reference points p1', p2', p3', and p4' in the glass instrument image are adjusted to form a regular rectangle can be calculated. The deviation between the operator's current observation position and the most accurate observation position can be obtained, and adjustment prompts (such as up, down, left, right, etc.) are generated for the operator to adjust the observation position and its observation angle. For example, using AR glasses, the operator can adjust the observation position by raising his head, turning his head, etc.

[0066] As in the solution of the above embodiment, the shooting position of the camera is used to simulate the observation position of the human eye, and the image of the glass instrument is used to detect whether the line of sight is tangent to the concave surface line of the liquid surface. In teaching, students can be trained on how to find the correct observation position and avoid looking down or up at the glass instrument to read the readings.

[0067] In one embodiment, in the experimental instrument equipment of the present application, when the terminal device 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 the liquid level change image; using tracking technology to identify the optical coding mark, and determining the target display position of the real-time reading information based on the optical coding mark; and displaying the real-time reading information according to the target display position.

[0068] Specifically, for each frame of the liquid level change image, the actual reading obtained after correction is generated, and corresponding real-time reading information is generated. For example, the accurate reading value can be directly generated, and the error value between the current directly observed volume reading and the actual reading can also be generated. Further, other information content related to the reading can be generated; AR motion tracking technology can be used to identify the optical coding mark printed on the glass instrument in real time, and combined with the identified liquid level position, the target display position where the real-time reading information needs to be displayed can be determined according to the optical coding mark; when using a smart phone, a display interface can be generated according to the liquid level change image, and the real-time reading information can be superimposed on the display interface according to the target display position for display. When using wearable devices, such as AR glasses, the real-time reading information can be projected onto the target display position. The user can observe the glass instrument through the AR glasses and obtain accurate readings and other information content related to the readings in real time.

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

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

[0071] Based on the solutions of the above embodiments, during the chemical experiment, students can use smartphones or wearable devices, etc., and use software to obtain accurate readings of glass instruments in real time, avoiding reading deviations; during experimental teaching, teachers no longer need to repeatedly instruct students to correct reading methods and calibrate glass instrument readings. Through software recognition, standardization of reading calibration can be achieved, and students can obtain accurate readings in real time, thereby greatly improving the efficiency and effectiveness of experimental teaching.

[0072] Several embodiments of the present application in titration experiments are described below. The measuring cylinder of the aforementioned embodiment can also be replaced by a burette, and the burette can also be printed with optical coding marks so that reading and identification can be performed during the titration experiment.

[0073] like Figure 7 As shown, Figure 7 This is a schematic diagram of a titration experiment. Since reading is one of the important contents of the titration experiment, different teachers have different experiences, so there will be parallax errors. The reading of the liquid level in the glass instrument needs to be observed by the naked eye at the lowest point of the concave surface of the liquid surface. It is affected by the observation angle (such as looking down, looking up, etc.) and ambient light, and the error range is large. During teaching, teachers need to repeatedly guide students to correct their reading methods, which takes up a lot of time, has low teaching efficiency, and is difficult to achieve standardized teaching, making it difficult to ensure teaching quality.

[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, fit a titration curve on the titration curve graph based on the actual readings and their corresponding solution parameters, and then dynamically display the titration curve on the display interface. The titration curve is obtained by fitting the solution parameter coordinate points calculated for each frame. For example, a smartphone or wearable device can automatically calculate the titration curve and endpoint judgment logic and dynamically display them. This can assist students in deeply mastering the titration process during the titration experiment, enhance the training effect of the experiment, and improve the teaching assistance effect.

[0075] For example, when dynamically displaying a titration curve, a camera can be used to capture the reading image of the potentiometric titrator in real time, and the corresponding reading can be 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. Specifically, during the titration process, a camera can be used to capture the reading image of the potentiometric titrator in real time to obtain the corresponding reading. When the reading is about to reach the endpoint, the reading image and the titration endpoint prompt are displayed in real time, thereby deepening the students' training effect on the titration experiment process.

[0076] Exemplarily, when dynamically displaying a titration curve, a camera can also be used to capture an image of the sample solution in a conical flask in real time, and the color presented in the sample solution can be identified from the sample solution image; when a color change is detected in the sample solution to which an indicator is added, a titration endpoint prompt is generated, and the titration endpoint prompt is placed at the position of the conical flask for real-time display. Specifically, during the titration process, the metering point or end point of the titration curve can be calculated based on the color change (indicator color). By displaying the relevant prompt content in real time based on the color presented in the sample solution, students can be reminded in real time during the titration experiment to pay attention to each key link of the experimental process, thereby improving teaching efficiency and enhancing the teaching and training effect of the titration experiment.

[0077] When using the terminal device of this embodiment, students can install the corresponding App tool on the terminal device. During the titration experiment, the camera of the terminal device can be used to shoot the glass instrument in real time. The terminal device can then display the observed glass instrument reading image in real time and also display the correct reading. This can train students to perform accurate readings, and the entire reading process can be standardized, which not only reduces the teacher's workload, but also avoids the impact of errors and improves teaching effectiveness.

[0078] The above description is only part of the implementation methods of the present application. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principles of the present application. These improvements and modifications should also be regarded as the scope of protection of the present application.

Claims

1. An experimental instrument, characterized in that: include: A glass instrument for measuring liquid volume, wherein the glass instrument is provided with an optically coded mark; A 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 method by the one or more processors: calling a camera to capture a video image of a glass instrument in real time, identifying an image of liquid level changes and its corresponding volume reading from the video image based on the optical coding mark; correcting the volume reading to obtain an 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.

2. The experimental instrument according to claim 1, characterized in that: The terminal device is a smart phone, 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 instrument according to claim 1, characterized in that: The one or more applications are configured to execute the following method by the one or more processors: The camera posture parameters of the camera are calculated according to the liquid level change image, the camera parameters of the camera and the instrument parameters of the glass instrument; and the volume reading is corrected according to the refractive index parameters of the glass instrument tube wall and the camera posture parameters to obtain the actual reading.

4. The experimental instrument according to claim 1, characterized in that: The one or more applications are configured to execute the following method by the one or more processors: Obtaining a liquid level change image for each frame of the video image, inputting the liquid level change image into a pre-trained deep learning model to obtain the liquid level position; performing edge detection on the liquid level position to identify the liquid surface concave line; The volume reading is determined based on the lowest point of the concave line of the liquid surface and the scale lines of the glass instrument.

5. The experimental instrument according to claim 3, characterized in that: The one or more applications are configured to execute the following method by the one or more processors: Identify a glass instrument image from the liquid level change image; obtain camera parameters of a camera and instrument parameters of the glass instrument; determine coordinate parameters of a reference point on the glass instrument image according to the instrument parameters, and calculate camera pose parameters of the camera according to the coordinate parameters and the camera parameters.

6. The experimental instrument according to claim 5, characterized in that: When calculating the camera pose parameters of the camera, the one or more applications are configured to execute the following method by the one or more processors: A plurality of reference points are selected on the glass instrument image; a first coordinate of each reference point in a coordinate system is determined according to the instrument parameters; a rotation matrix and a translation vector of the camera are calculated according to the first coordinates and the camera parameters, and a relative position and a shooting angle between the camera and the glass instrument are determined according to the rotation matrix and the translation vector.

7. The experimental instrument according to claim 6, characterized in that: When correcting the volume reading to obtain the actual reading, the one or more applications are configured to execute the following method by the one or more processors: Obtain a second coordinate of the liquid level position in the coordinate system; obtain a third coordinate of the camera in the coordinate system based on the relative position; determine a 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 compensate the volume reading for the tube wall refractive index based on the optical path model to obtain an actual reading of the glass instrument.

8. The experimental instrument according to claim 7, characterized in that: The one or more applications are configured to execute the following method by the one or more processors: The sight deviation angle is calculated according to the first coordinate of the reference point of the glass instrument image and the position of the liquid surface concave line in the burette image, the adjustment direction of the camera is calculated according to the deviation angle, and corresponding prompt information is generated for display.

9. The experimental instrument according to claim 1, characterized in that: The one or more applications are configured to execute the following method by the one or more processors: Generate corresponding real-time reading information based on the actual reading of each frame of liquid level change image; use tracking technology to identify the optical coding mark, and determine the target display position of the real-time reading information based on the optical coding mark; and display the real-time reading information according to the target display position.

10. A glass instrument for measuring the volume of a liquid, characterized in that: An optical coding mark is printed on the surface of the glass instrument; the glass instrument is used for the experimental instrument equipment according to any one of claims 1 to 9.

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