Vibration measurement method, system and device, computer equipment and storage medium

Abstract

The invention provides a vibration measurement method, system and device, computer equipment and a storage medium. The method comprises the following steps: controlling an image acquisition unit to acquire a plurality of continuous measurement images from a measurement unit; respectively determining first position information corresponding to the clearest area in each measurement image; the first position information reflects the position of the clearest area in the measurement image in the measurement direction of the measurement image, and the measurement direction is the direction in which the object distance corresponding to the pixel point in the image formed by the image acquisition unit changes; obtaining corresponding second position information according to a preset mapping relation and the first position information; the second position information reflects the object distance corresponding to the clearest area in the measurement image; and obtaining vibration information of the measured object according to the second position information. The method can realize high-precision measurement, especially has advantages in measurement of tiny vibration, has low requirements on the surface of a measured object, and is more convenient to use.

Description

Technical Field

[0001] The present application relates to the field of vibration measurement technology, and in particular to a vibration measurement method, system, device, computer equipment and storage medium. Background Art

[0002] Vibration is one of the most common phenomena in nature and is ubiquitous in the field of engineering technology. In particular, micro-vibration refers to vibration with a frequency of 2~100 Hz and an amplitude of less than 50um / s. Indoor equipment operation, noise, outdoor transportation, factory construction, etc. are all sources of micro-vibration. On the one hand, vibration has a great impact on all kinds of measurements, especially in the field of microscopic measurement with high precision requirements. On the other hand, vibration is harmful in many cases. For example, vibration will reduce processing accuracy and finish, and aggravate the wear of structural components. Therefore, people have developed various vibration isolation devices, which can be roughly divided into active vibration isolation and passive vibration isolation, such as vibration isolation tables, vibration isolation foot pads, etc. Regardless of the type of vibration isolation equipment, in order to achieve the best vibration isolation effect, it is necessary to have a deep understanding of the nature of the vibration source, such as the type, frequency, amplitude, etc. of vibration. One of the important ways to understand this information is to measure the vibration. However, traditional vibration measurement methods often have problems such as low measurement frequency and accuracy, high requirements for the surface of the object, and inconvenient use. Summary of the invention

[0003] The purpose of this application is to solve at least one of the above-mentioned technical defects, especially the defects of vibration measurement in the prior art, such as low measurement frequency and accuracy, high requirements on the surface of the object, and inconvenient use.

[0004] In a first aspect, the present application provides a vibration measurement method, which is applied to a vibration measurement system. The vibration measurement system includes an image acquisition unit and a measurement unit. The measurement unit is fixed to the object to be measured. There is a preset angle between the imaging surface of the image acquisition unit and the measurement surface of the measurement unit. The vibration measurement method includes:

[0005] Controlling the image acquisition unit to acquire a plurality of continuous measurement images for the measurement unit;

[0006] Determine first position information corresponding to the clearest area in each measurement image respectively; the first position information reflects the position of the clearest area in the measurement image in the measurement direction of the measurement image, and the measurement direction is the direction in which the object distance corresponding to the pixel point in the image captured by the image acquisition unit changes;

[0007] According to the preset mapping relationship and each first position information, the corresponding second position information is obtained; the second position information reflects the object distance corresponding to the clearest area in the measurement image;

[0008] According to each second position information, vibration information of the measured object is obtained.

[0009] In one embodiment, respectively determining the first position information corresponding to the clearest area in each measurement image includes:

[0010] respectively determining the definition distribution curve of each measurement image in the measurement direction;

[0011] The first position information is obtained according to the peak position in the clarity distribution curve.

[0012] In one embodiment, the vibration measurement system further includes a focusing unit, which is used to change the position of the image acquisition unit to adjust the distance between the image acquisition unit and the measurement unit; before controlling the image acquisition unit to acquire a plurality of continuous measurement images of the measurement unit, the system further includes:

[0013] Controlling the focusing unit to adjust the image acquisition unit to a plurality of calibration positions according to a set step length, and controlling the image acquisition unit to acquire a corresponding calibration image at each calibration position;

[0014] Determine first calibration position information corresponding to each calibration position according to the calibration image corresponding to each calibration position; the first calibration position information reflects the position of the clearest area in the calibration image corresponding to the calibration position in the measurement direction of the calibration image;

[0015] Determine second calibration position information corresponding to each calibration position according to the object distance corresponding to the clearest area in the calibration image corresponding to each calibration position;

[0016] Fitting is performed according to the first calibration position information and the second calibration position information corresponding to each calibration position to obtain a mapping relationship.

[0017] In one embodiment, controlling the image acquisition unit to acquire the corresponding calibration image at each calibration position includes:

[0018] The image acquisition unit is controlled to acquire a plurality of calibration images at each calibration position.

[0019] In one embodiment, determining first calibration position information corresponding to each calibration position according to the calibration image corresponding to each calibration position includes:

[0020] For the same calibration position, first calibration position information corresponding to the calibration position is obtained according to an average value of positions of the clearest areas in each calibration image at the calibration position in the measurement direction of the calibration image.

[0021] In one embodiment, before controlling the image acquisition unit to acquire a plurality of continuous measurement images for the measurement unit, the method further includes:

[0022] Determine the upper and lower vibration limits of the measured object in the normal direction; the upper and lower vibration limits are respectively the closest and farthest object distances to the image acquisition unit when the measured object vibrates with the initial position as the starting point;

[0023] According to the mapping relationship and the vibration upper limit, a first measurement threshold is obtained;

[0024] According to the mapping relationship and the vibration lower limit, a second measurement threshold is obtained;

[0025] Determine a measurement starting point in the image formed by the image acquisition unit so that the distance from the measurement starting point to the image boundary in the positive direction of the measurement direction is not less than a first measurement threshold, and the distance from the measurement starting point to the image boundary in the negative direction of the measurement direction is not less than a second measurement threshold;

[0026] The position of the image acquisition unit is adjusted so that the clearest area imaged by the image acquisition unit matches the measurement starting point.

[0027] In one embodiment, determining the measurement starting point in the imaging plane further includes:

[0028] If the measurement starting point cannot be found, the tilt direction of the image acquisition unit is adjusted to change the measurement direction;

[0029] The mapping relationship corresponding to the new measurement direction is re-determined, and the step of obtaining the first measurement threshold value according to the mapping relationship and the vibration upper limit is returned to continue execution.

[0030] In one of the embodiments, the pattern arranged on the measurement surface is a periodically changing texture.

[0031] In one embodiment, the periodically changing texture is parallel line segments with equal intervals.

[0032] In one embodiment, the vibration measurement system further includes an amplification unit, which is disposed between the image acquisition unit and the measurement unit and is used to amplify the image of the measurement unit, and the amplification factor of the amplification unit is adjustable. Before controlling the image acquisition unit to acquire a plurality of continuous measurement images of the measurement unit, the system further includes:

[0033] According to the density of the line segments, the resolution coefficient threshold is determined;

[0034] In the amplification unit, an amplification factor whose resolution factor is not less than a resolution factor threshold is selected.

[0035] In a second aspect, the present application provides a vibration measurement system, including an image acquisition unit, a measuring unit and a control unit. The measuring unit is fixed to the object to be measured. There is an angle of a preset angle between the imaging surface of the image acquisition unit and the measuring surface of the measuring unit. The control unit is configured to execute the steps of the vibration measurement method in any of the above embodiments.

[0036] In one of the embodiments, the vibration measurement system further includes a focusing unit, which is used to change the position of the image acquisition unit to adjust the distance between the image acquisition unit and the measurement unit.

[0037] In one of the embodiments, the vibration measurement system further includes an amplification unit, which is disposed between the image acquisition unit and the measurement unit and is used to amplify the image of the measurement unit, and the amplification factor of the amplification unit is adjustable.

[0038] In one embodiment, the vibration measurement system further includes an angle adjustment unit for adjusting the angle between the imaging surface and the measurement surface.

[0039] In one of the embodiments, the vibration measurement system further includes a direction adjustment unit for adjusting the shooting direction of the image acquisition unit.

[0040] In one of the embodiments, the pattern arranged on the measurement surface is a periodically changing texture.

[0041] In one embodiment, the periodically changing texture is parallel line segments with equal intervals.

[0042] In one embodiment, the vibration measurement system further includes a fill light unit, and the fill light unit is used to provide fill light for the measurement unit.

[0043] In one embodiment, the fill light unit includes a fixed base and a backlight source. The fixed base is used to detachably fix the measuring unit on the object to be measured. A light-transmitting window is provided on the fixed base. The backlight source is used to fill light for the measuring unit through the light-transmitting window.

[0044] In a third aspect, the present application provides a vibration measurement device, which is applied to a vibration measurement system. The vibration measurement system includes an image acquisition unit and a measurement unit. The measurement unit is fixed to the object to be measured. There is a preset angle between the imaging surface of the image acquisition unit and the measurement surface of the measurement unit. The vibration measurement device includes:

[0045] An image acquisition module, used to control the image acquisition unit to acquire a plurality of continuous measurement images for the measurement unit;

[0046] A first position information acquisition module is used to respectively determine the first position information corresponding to the clearest area in each measurement image; the first position information reflects the position of the clearest area in the measurement image in the measurement direction of the measurement image, and the measurement direction is the direction in which the object distance corresponding to the pixel point in the image captured by the image acquisition unit changes;

[0047] A second position information acquisition module is used to obtain corresponding second position information according to a preset mapping relationship and each first position information; the second position information reflects the object distance corresponding to the clearest area in the measurement image;

[0048] The vibration information determination module is used to obtain the vibration information of the measured object according to each second position information.

[0049] In a fourth aspect, the present application provides a computer device, comprising one or more processors and a memory, wherein the memory stores computer-readable instructions, and when the computer-readable instructions are executed by the one or more processors, the steps of the vibration measurement method in any of the above embodiments are performed.

[0050] In a fifth aspect, the present application provides a storage medium storing computer-readable instructions. When the computer-readable instructions are executed by one or more processors, the one or more processors execute the steps of the vibration measurement method in any of the above embodiments.

[0051] It can be seen from the above technical solutions that the embodiments of the present application have the following advantages:

[0052] The vibration measurement method in this embodiment uses an image acquisition unit to collect multiple continuous images of the measuring unit fixed on the object to be measured. Then, the first position information corresponding to the clearest area is determined in each image. Then, the first position information is converted into the second position information through a pre-established mapping relationship. Finally, based on the time series of the second position information, the vibration characteristics of the object to be measured are analyzed. This method is a non-contact measurement method, which avoids the interference that traditional contact sensors may cause to the object to be measured, and can more accurately reflect the true vibration state of the object. Secondly, through optical imaging and image processing technology, this method can achieve high-precision measurement, especially in the measurement of small vibrations. In addition, in this measurement method, the way in which the measuring unit is fixed on the object to be measured is relatively free, the surface requirements of the object to be measured are relatively low, and it is more convenient to use. BRIEF DESCRIPTION OF THE DRAWINGS

[0053] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0054] Figure 1 Schematic diagram of the principle of the vibration measurement method in this application;

[0055] Figure 2A schematic diagram of a flow chart of a vibration measurement method provided in one embodiment of the present application;

[0056] Figure 3 A schematic diagram of a measurement direction in one embodiment of the present application;

[0057] Figure 4 A schematic diagram of a process of calibrating and obtaining a mapping relationship in one embodiment of the present application;

[0058] Figure 5 A schematic diagram of a process for determining a measurement starting point in one embodiment of the present application;

[0059] Figure 6 A schematic diagram of selecting a measurement starting point in one embodiment of the present application;

[0060] Figure 7 A schematic diagram of selecting a measurement starting point in another embodiment of the present application;

[0061] Figure 8 A schematic diagram of the structure of a vibration measurement system provided by one embodiment of the present application;

[0062] Fig. 9 A schematic diagram of multiple different strategy units provided in one embodiment of the present application;

[0063] Fig.10 An exploded diagram of a fill light unit and a measuring unit in one embodiment of the present application;

[0064] Fig.11 This is an assembly diagram of a fill light unit and a measuring unit in one embodiment of the present application;

[0065] Fig.12 An internal structure diagram of a computer device provided for one embodiment of the present application. DETAILED DESCRIPTION

[0066] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0067] The present application provides a vibration measurement method, which is applied to a vibration measurement system, and the vibration measurement system includes an image acquisition unit and a measurement unit. The image acquisition unit (such as a camera) is used to acquire images, and the measurement unit is fixed to the object to be measured, so that when the object to be measured vibrates, the measurement unit will vibrate in the same manner as the object to be measured, that is, the two have the same vibration state. When the image acquisition unit acquires images toward the measurement surface of the measurement unit, so that when the measurement surface vibrates in the normal direction, the object distance of the measurement surface will change accordingly. An image sensor (such as a CMOS image sensor, a CCD image sensor) is arranged in the image acquisition unit, and the measurement surface of the measurement unit will eventually be imaged on a plane in the image sensor (such as the plane where the photosensitive element is located), which is called an imaging plane (also called an image plane). If the object to be measured vibrates in only one direction, a set of measurement units and image acquisition units can meet the test requirements, and the measurement surface should be perpendicular to the vibration direction. If the vibration of the object to be measured can be decomposed into more than two directions, the same number of measurement units and image acquisition units as the decomposed vibration directions are required, and the measurement surface of each measurement unit is perpendicular to the corresponding vibration direction.

[0068] In an optical imaging system, when the focal length and image distance are fixed, the object distance and the image formed will form a single-peak function relationship similar to Gaussian distribution, and its peak position corresponds to the focal plane position. Therefore, when the image acquisition unit acquires an image of the measurement surface, if the imaging surface and the measurement surface are parallel to each other, it means that each position on the measurement surface has the same object distance, and each point on the measurement surface has the same clarity. If there is an angle between the imaging surface and the measurement surface, such as Figure 1 As shown, there will be points with different object distances on the measuring surface, resulting in different clarity of these points in the imaging, and the clarity of each point on the imaging surface along the direction of object distance change will present a unimodal function relationship. In the case where there is an angle between the measuring surface and the imaging surface, when the measuring surface vibrates in the direction of its normal, the object distance of the measuring surface will change synchronously with the amplitude of the vibration, so that the image of the unimodal function will translate as a whole in its coordinate system, and its peak position is taken to represent the position of the entire function image. It can be observed that its peak position changes with the vibration of the measuring surface in the normal direction. Therefore, based on this principle, the present application establishes a connection between the peak position and the vibration of the object being measured, and determines the vibration of the object being measured by detecting the change in the peak position. The present application sets an angle of a preset angle between the imaging surface of the image acquisition unit and the measuring surface of the measuring unit. In order to facilitate measurement in actual operation, the preset angle can be achieved by controlling the inclination of the imaging surface. Of course, it can also be achieved by changing the angle of the measuring surface. Specifically, please refer to Figure 2 , the vibration measurement method includes steps S202 to S208.

[0069] S202: Control the image acquisition unit to acquire a plurality of continuous measurement images for the measurement unit.

[0070] It can be understood that the measurement image is the image obtained by shooting the image acquisition unit toward the measurement surface of the measurement unit. The multiple measurement images here are at least two. The reason for collecting multiple measurement images is that vibration is a dynamic process. A single image can only reflect the position of the measurement surface at a certain moment, and the change of position can be obtained based on multiple continuous images, so as to analyze the vibration of the object under test. In addition, in order to better collect the vibration of the object under test, it is necessary to pay attention to the frame rate of the image acquisition unit. As the vibration frequency of the object under test increases, the frame rate of the selected image acquisition unit should also increase accordingly. Therefore, in some cases, the image acquisition unit needs to use a high-speed camera or a high frame rate camera.

[0071] S204, respectively determine the first position information corresponding to the clearest area in each measurement image. The first position information reflects the position of the clearest area in the measurement image in the measurement direction of the measurement image, and the measurement direction is the direction in which the object distance corresponding to the pixel point in the image captured by the image acquisition unit changes.

[0072] It can be understood that in an optical imaging system, due to the angle between the imaging surface and the measuring surface, the object distances at different positions on the measuring surface will be different, which leads to differences in the clarity of the corresponding areas of each point on the measuring surface in the measuring image. The clearest area refers to the part with the highest clarity in the image. There is a one-to-one correspondence between the pixel points obtained based on the measuring surface in the measuring image and the various areas of the measuring surface. Due to the existence of the preset angle, the object distances of these areas will change. In the image formed by the image acquisition unit, the corresponding object distances of each pixel point passed along the measuring direction will change the fastest. Therefore, the measurement direction is defined as the direction in which the object distance corresponding to the pixel point in the image formed by the image acquisition unit changes. Figure 1 The tilt angle shown is viewed from the front, the short sides of the imaging surface and the measuring surface are parallel to each other, and the long sides have a preset angle. Then the object distance corresponding to each pixel point of the formed image changes fastest along the long side of the formed image, such as Figure 3 shown.

[0073] The object distance of each point in the measurement direction is different, so the clarity of the corresponding image will also be different. During the measurement phase, the position of the clearest part in the measurement direction of the measurement image is the first position information. Due to the vibration of the measured object, the position of the clearest area in different measurement images will change, which is the key information we use to analyze the vibration. This analysis process needs to be performed separately for each measurement image to obtain a series of first position information that changes over time.

[0074] If the position is represented by coordinates, an origin can be selected in the measurement direction, with the distance between each point and the origin in the measurement direction as the horizontal axis, and the clarity of the image corresponding to each point as the vertical axis, to form a clarity distribution curve in the measurement phase. Specifically, the clarity distribution curve can be a plurality of sampling points selected between the boundaries at both ends of the measurement direction according to a preset interval. The distance between each sampling point and the origin in the measurement direction is determined as the horizontal coordinate, and the vertical coordinate of the clarity corresponding to each sampling point is determined. Then the selected unimodal function curve is used to fit the coordinate pairs of these sampling points (i.e., the coordinate pairs composed of the corresponding horizontal coordinates and vertical coordinates) to obtain the clarity distribution curve. The selected unimodal function curve can be a parabola, a Gaussian curve, a Lorentz curve, etc. The horizontal coordinate corresponding to the peak position of the clarity distribution curve in the measurement phase is the first position information. In addition, there are many ways to represent the clarity of an image in the field of images, which are exemplary but not limiting, such as Brenner gradient, Tenegrad gradient, Laplace gradient, central difference operator, etc. The specific method of representing the clarity of the image can be selected according to actual needs.

[0075] S206, obtaining corresponding second position information according to the preset mapping relationship and each first position information. The second position information reflects the object distance corresponding to the clearest area in the measurement image.

[0076] It can be understood that after research and analysis, it is found that when there is an angle between the imaging surface and the measuring surface, if the measuring surface changes its position along the normal direction, the first position information corresponding to the formed image will also change. That is, there is a mapping relationship between the first position information and the change in the object distance of the measuring surface, and this mapping relationship can be obtained by fitting based on a certain amount of data. Therefore, before starting the measurement, the entire system can be calibrated first, and the mapping relationship corresponding to the current system configuration (such as the selection of preset angles, tilt directions, etc.) can be obtained by fitting.

[0077] During the measurement phase, the second position information is defined as reflecting the object distance corresponding to the clearest area in the measurement image. The image of a certain position on the measurement surface is the clearest in the entire image, and the second position information reflects the object distance corresponding to the position. This step requires that the first position information obtained based on each measurement image be converted into corresponding second position information. Since the measurement surface is perpendicular to a vibration direction of the object being measured, the normal direction of the measurement surface is parallel to the vibration direction. The second position information can represent the position of the measurement surface in the vibration direction at multiple consecutive moments. After determining the mapping relationship, the first position information can be input into the mapping relationship to obtain the corresponding second position information.

[0078] S208: Obtain vibration information of the measured object according to each piece of second position information.

[0079] It can be understood that the second position information reflects the change in the object distance of the measuring unit, and these position changes directly correspond to the vibration displacement of the measured object. By analyzing the change of the second position information over time, we can obtain the detailed vibration characteristics of the measured object. Vibration information can include vibration amplitude, vibration waveform, phase information, harmonic components, etc. The vibration amplitude can be calculated by the difference between the maximum and minimum values ​​of the second position information. The vibration frequency can be obtained by Fourier transforming the second position information or by calculating the time interval between adjacent peaks. The vibration waveform can be directly represented by the curve of the change of the second position information over time. In addition, more detailed features such as phase information and harmonic components of vibration may also be included. In actual analysis, it may be necessary to apply signal processing technology to improve the quality and reliability of the data. For example, filtering technology can be used to remove noise, interpolation technology can be used to improve time resolution, or statistical methods can be used to improve the stability and repeatability of measurement.

[0080] The vibration measurement method in this embodiment uses an image acquisition unit to collect multiple continuous images of the measuring unit fixed on the object to be measured. Then, the first position information corresponding to the clearest area is determined in each image. Then, the first position information is converted into the second position information through a pre-established mapping relationship. Finally, based on the time series of the second position information, the vibration characteristics of the object to be measured are analyzed. This method is a non-contact measurement method, which avoids the interference that traditional contact sensors may cause to the object to be measured, and can more accurately reflect the true vibration state of the object. Secondly, through optical imaging and image processing technology, this method can achieve high-precision measurement, especially in the measurement of small vibrations. In addition, in this measurement method, the way in which the measuring unit is fixed on the object to be measured is relatively free, the surface requirements of the object to be measured are relatively low, and it is more convenient to use.

[0081] In one embodiment, the vibration measurement system further includes a focusing unit, which is used to change the position of the image acquisition unit to adjust the object distance. Figure 4 , before controlling the image acquisition unit to acquire a plurality of continuous measurement images for the measurement unit, it also includes steps S402 to S408.

[0082] S402, controlling the focus adjustment unit to adjust the image acquisition unit to a plurality of calibration positions according to a set step length, and controlling the image acquisition unit to acquire a corresponding calibration image at each calibration position.

[0083] It can be understood that the mapping relationship between the first position information and the second position information needs to be obtained in advance. Therefore, before starting vibration detection, the mapping relationship needs to be calibrated. The calibration position refers to the different positions of the image acquisition unit relative to the measuring unit during the calibration phase. The object distances corresponding to each calibration position are different, which will cause the peak positions of the clarity distribution curves corresponding to each calibration position to change accordingly. During the calibration phase, the image acquired by the image acquisition unit is the calibration image. After the calibration starts, the image acquisition unit needs to control the image acquisition unit to acquire images of the measuring unit each time it is in a calibration position to obtain a calibration image corresponding to each calibration position. The calibration image acquired by the image acquisition unit at each position can be one or more. In addition, the setting step size can be adjusted as needed. Selecting a smaller setting step size can obtain more data and achieve higher accuracy in fitting. Selecting a longer setting step size can improve the efficiency of fitting. The setting step size can be kept fixed throughout the calibration phase or can be changed during the calibration process.

[0084] S404: Determine first calibration position information corresponding to each calibration position according to the calibration image corresponding to each calibration position. The first calibration position information reflects the position of the clearest area in the calibration image corresponding to the calibration position in the measurement direction of the calibration image.

[0085] It can be understood that the definition of the first calibration position information is similar to that of the first position information, the difference being that the former is a concept in the calibration phase, while the latter is a concept in the measurement phase. In the calibration image corresponding to each calibration position, due to the angle between the imaging surface and the measurement surface, the clarity of the corresponding areas of each point on the measurement surface in the calibration image is different. The clearest area refers to the part with the highest clarity in the image. In the calibration phase, the corresponding position of the part with the highest clarity in the measurement direction of the calibration image is the first calibration position information.

[0086] If only one calibration image is collected at each calibration position, the position of the clearest area in the calibration image in the measurement direction of the calibration image is directly used as the first calibration position information. If multiple calibration images are collected at each calibration position, for the same calibration position, the positions of the clearest areas in each calibration image at the calibration position in the measurement direction of the calibration image are determined respectively, and then the average of these positions is calculated to obtain the first calibration position information corresponding to the calibration position. This method increases the accuracy of the first calibration position information obtained at each calibration position and improves the reliability of the mapping relationship.

[0087] In addition, determining the corresponding position of the clearest area in the calibration image in the measurement direction of the measurement surface in the calibration stage is similar to the above description. That is, if the position is expressed in coordinates, an origin can be selected in the measurement direction, with the distance between each point in the measurement direction and the origin as the horizontal axis, and the clarity of the corresponding imaging of each point as the vertical axis, to form a clarity distribution curve in the calibration stage. Among them, the horizontal coordinate corresponding to the peak position of the clarity distribution curve in the calibration stage is the position of the clearest area in the calibration image in the measurement direction of the calibration image. Specifically, the clarity distribution curve can be selected according to a preset interval between the boundaries at both ends of the measurement direction. The distance of each sampling point from the origin in the measurement direction is determined as the horizontal coordinate, and the vertical coordinate of the clarity corresponding to each sampling point is determined. Then, the selected unimodal function curve is used to fit the coordinate pairs of these sampling points (i.e., the coordinate pairs composed of the corresponding horizontal coordinates and vertical coordinates) to obtain the clarity distribution curve. The selected unimodal function curve can be a parabola, a Gaussian curve, a Lorentz curve, etc. The horizontal coordinate corresponding to the peak position of the clarity distribution curve in the measurement stage is the first position information. In addition, there are many ways to express image clarity in the image field, which are exemplary but not limiting, such as Brenner gradient, Tenegrad gradient, Laplace gradient, central difference operator, etc. The specific method to express image clarity can be selected according to actual needs. The image clarity expression method selected in the measurement stage and the calibration stage should be consistent.

[0088] S406 , determining second calibration position information corresponding to each calibration position according to the object distance corresponding to the clearest area in the calibration image corresponding to each calibration position.

[0089] It can be understood that the object distance here refers to the distance between a certain position on the measurement surface and the image acquisition unit. Since each calibration position is selected under the control of the entire system, when the image acquisition unit is at each calibration position, the object distance corresponding to the position where the clearest area is imaged on the measurement surface can also be measured. The measurement method can refer to the mature technologies in the fields of optical imaging and microscopic imaging. This step can directly use the object distance corresponding to the clearest area in the calibration image corresponding to each calibration position.

[0090] S408: Perform fitting according to the first calibration position information and the second calibration position information corresponding to each calibration position to obtain a mapping relationship.

[0091] It can be understood that each calibration position corresponds to a set of first calibration position information and second calibration position information, and multiple sets of first calibration position information and second calibration position information can be used for data fitting to find a function that can best describe the relationship between the first calibration position information and the second calibration position information. After research, it was found that there is generally a linear relationship between the first calibration position information and the second calibration position information, such as z=ax+b. Among them, x represents the first calibration position information in the measurement stage, and z represents the second calibration position information in the calibration stage. a and b are parameters obtained during linear fitting, and a is proportional to the sine of the preset angle. If an amplification unit is provided between the measuring unit and the image acquisition unit to amplify the imaging, a is also inversely proportional to the square of the magnification of the amplification unit.

[0092] In one embodiment, before controlling the image acquisition unit to acquire a plurality of continuous measurement images for the measurement unit, refer to Figure 5 , also includes steps S502 to S510.

[0093] S502, determining the upper and lower vibration limits of the measured object in the normal direction. The upper and lower vibration limits are respectively the closest and farthest object distances to the image acquisition unit when the measured object vibrates with the initial position as the starting point.

[0094] It can be understood that before starting the measurement, in addition to determining the mapping relationship corresponding to the current configuration, the positions of the image acquisition unit and the measurement unit can also be adjusted. Specifically, the vibration of the measured object in the normal direction will change the object distance, so that the area with the clearest imaging moves in the measurement direction of the imaging. When the measured object is closest and farthest from the image acquisition, the clearest area also moves to the two extreme positions in the measurement direction in the imaging. If the clearest area exceeds the boundary of the imaging, the clearest area will not be detected, thereby affecting the vibration measurement. Therefore, the position of the clearest area in the measurement image at the beginning of the measurement (ie, the measurement starting point) is reasonably selected, and the imaging range can be reasonably utilized. For some measurement scenarios, the vibration amplitude of the measured object can be predicted, estimated or analyzed in advance. In these scenarios, the upper and lower vibration limits can be determined respectively to assist in the selection of the measurement starting point.

[0095] S504: Obtain a first measurement threshold value according to the mapping relationship and the upper vibration limit.

[0096] S506: Obtain a second measurement threshold according to the mapping relationship and the vibration lower limit.

[0097] It can be understood that the mapping relationship is established during the calibration process, which describes the mapping relationship between the position in the measurement direction in the image and the object distance. When the measured object approaches the image acquisition unit, the direction in which the clearest area moves along the measurement direction is defined as the positive direction, and when the measured object moves away from the image acquisition unit, the direction in which the clearest area moves along the measurement direction is defined as the reverse direction. First, determine the position information of the clearest area in the measurement direction when the measured object is at the initial position as the reference position information.

[0098] When the measured object moves to the upper limit of vibration, its object distance is the smallest, and the clearest area also moves to an extreme position in the positive direction of the measurement direction. According to the upper limit of vibration and the mapping relationship, the first extreme position information of the extreme position in the measurement direction can be obtained. According to the distance between the first extreme position information and the reference position information in the measurement direction, the first measurement threshold can be obtained. The first measurement threshold reflects the extreme offset of the clearest area on the image when vibrating upward from the initial position of vibration.

[0099] Similarly, when the measured object moves to the lower limit of vibration, its object distance is the largest, and the clearest area also moves to another extreme position in the opposite direction of the measurement direction. According to the lower limit of vibration and the mapping relationship, the second extreme position information of the extreme position in the measurement direction can be obtained. According to the distance between the second extreme position information and the reference position information in the measurement direction, the second measurement threshold can be obtained. The second measurement threshold reflects the extreme offset of the clearest area on the image when vibrating downward from the initial position of vibration.

[0100] S508, determining a measurement starting point in the image captured by the image acquisition unit, so that the distance from the measurement starting point to the image boundary along the positive direction of the measurement direction is not less than a first measurement threshold, and the distance from the measurement starting point to the image boundary along the negative direction of the measurement direction is not less than a second measurement threshold.

[0101] It can be understood that after determining the first measurement threshold and the second measurement threshold, a suitable measurement starting point can be selected from the image according to the two thresholds. Specifically, the selected measurement starting point is the position of the clearest area at the beginning of the measurement. When the object to be measured approaches the image acquisition unit, the clearest area will move in the positive direction of the measurement direction in the image, and the offset of the movement will not exceed the first measurement threshold. Therefore, to ensure that the clearest area does not move out of the boundary of the image, it is necessary to ensure that the distance from the measurement starting point along the positive direction of the measurement direction to the image boundary is not less than the first measurement threshold. When the object to be measured is away from the image acquisition unit, the clearest area will move in the reverse direction of the measurement direction in the image, and the offset of the movement will not exceed the second measurement threshold. Therefore, to ensure that the clearest area does not move out of the boundary of the image, it is necessary to ensure that the distance from the measurement starting point along the reverse direction of the measurement direction to the image boundary is not less than the second measurement threshold.

[0102] It is worth mentioning that the vibration conditions in some vibration scenes are not symmetrical, that is, the upper and lower vibration limits may have different offsets from the initial position. Therefore, the measurement starting point does not necessarily need to be located at the center of the entire image. Figure 6 For example, in Figure 3 In the imaging shown, if the offset between the upper vibration limit and the initial position is greater than the offset between the lower vibration limit and the initial position, the first measurement threshold will be greater than the second measurement threshold. If the first measurement threshold is greater than half of the long side of the imaging, placing the measurement starting point at the midpoint of the measurement direction will result in the distance from the measurement starting point to the image boundary in the positive direction along the measurement direction being less than the second measurement threshold. In this case, it is necessary to Figure 6 As shown, select the measurement starting point slightly to the left.

[0103] S510, adjusting the position of the image acquisition unit so that the clearest area imaged by the image acquisition unit matches the measurement starting point.

[0104] It is understood that the sharpest area usually corresponds to the current position of the object being measured, and aligning it with the measurement starting point ensures that the entire vibration process can be effectively captured. The adjustment process may involve physical movement of the image acquisition unit (for example, adjusting the object distance through the focus unit), or adjusting the position of the measurement unit on the mount. This adjustment process may require multiple iterations, and after each adjustment, the image needs to be re-captured and the sharpness distribution analyzed until the best match is achieved.

[0105] In one embodiment, determining the measurement starting point in the imaging plane further includes: if the measurement starting point cannot be found, adjusting the tilt direction of the image acquisition unit to change the measurement direction, re-determining the mapping relationship corresponding to the new measurement direction, and returning to the step of obtaining the first measurement threshold according to the mapping relationship and the vibration upper limit to continue execution.

[0106] It is understandable that in actual operation, it is possible that any point in the measurement direction of the image cannot meet the requirements. Figure 7 In the case shown above, both boundaries from the measurement start point to the measurement direction cannot meet the requirements. In this case, it means that the currently selected measurement direction does not match the upcoming vibration test, and the measurement direction needs to be changed. The measurement direction is the direction in which the object distance corresponding to the pixel point in the image captured by the image acquisition unit changes. When the tilt direction of the imaging surface changes, the measurement direction will change. The tilt direction of the imaging surface can be achieved by rotating it in space (for example, rotating around its center).

[0107] like Figure 1 After the imaging surface in the image is rotated counterclockwise, the measurement direction can also change until it changes to Figure 7In the case below, the measurement starting point can be found. However, it is worth mentioning that some clarity calculations need to refer to multiple pixel points perpendicular to the measurement direction. Figure 7 In the case shown above, the number of pixels distributed at each position in the measurement direction is the same, and the resulting clarity distribution curve is of good quality. Figure 7 In the case shown below, there will be a problem of a small number of pixels corresponding to the two ends, and the quality of the obtained clarity distribution curve will be affected. Therefore, when selecting the measurement direction, you should pay attention to whether the number of available pixels at each position is higher than the lower limit to ensure the quality of the curve.

[0108] After the measurement direction is changed, the current mapping relationship no longer matches the new measurement direction and needs to be re-mapped. Figure 4 The process in is calibrated to obtain a mapping relationship matching the new measurement direction. After obtaining the new mapping relationship, the process returns to step S504 to continue execution and find a suitable measurement starting point after the measurement direction is changed.

[0109] In one of the embodiments, a pattern is provided on the measuring surface, and when the measured object vibrates in the normal direction, the clearest area of ​​the pattern in the imaging will shift. This is because the present application needs to rely on the vibration of the measured object to detect the position change of the clearest area. If no pattern is provided or the image of the pattern is completely consistent when the measured object vibrates, it cannot be implemented using the solution in the present application. In a specific embodiment, on the basis of meeting the above requirements, the pattern provided on the measuring surface can be selected as a periodically changing texture. For example, equally spaced grids, parallel line segments, etc.

[0110] In one of the embodiments, the vibration measurement system further includes an amplification unit, which is disposed between the image acquisition unit and the measurement unit, and is used to amplify the image of the measurement unit, and the amplification factor of the amplification unit is adjustable. In order to detect tiny vibrations, the size of the pattern set on the measurement surface also needs to be reduced accordingly. In order to enable the image acquisition unit to distinguish the pattern, it is necessary to introduce an amplification unit, and select a suitable amplification factor for the amplification unit. Therefore, before controlling the image acquisition unit to acquire multiple continuous measurement images of the measurement unit, it also includes: determining a resolution coefficient threshold according to the density of the line segment. The amplification unit selects a magnification factor with a resolution coefficient not less than the resolution coefficient threshold.

[0111] It can be understood that the resolution factor is an indicator of the resolution ability of the optical system, which is related to the minimum detail size that the system can resolve. The resolution factor threshold is the minimum resolution requirement set according to the specific measurement requirements. In the process of determining the resolution factor threshold, the density of the line segment needs to be considered. The line segment density here refers to the density of the equally spaced line segment texture on the measurement surface, usually expressed as the number of line segments per unit length. The higher the line segment density, the larger the resolution factor is required to ensure that the system can clearly distinguish each line segment. The system will choose to use a magnification factor that is not less than the resolution factor threshold, which ensures that the system can clearly distinguish the line segment texture on the measurement surface. In a specific embodiment, the resolution factor can be selected as the numerical aperture. The resolution factor threshold can be obtained by dividing the density of the line segment by 3000. The numerical aperture of the selected magnification unit should not be less than the resolution factor threshold.

[0112] The present application provides a vibration measurement system 100. Figure 8 , including an image acquisition unit 10, a measuring unit 20 and a control unit (not shown in the figure). The measuring unit 20 is fixed to the object to be measured 200, and there is a preset angle between the imaging surface of the image acquisition unit 10 and the measuring surface of the measuring unit 20, and the control unit is configured to perform the steps of the vibration measurement method in any of the above embodiments. The entire vibration measurement system can be improved on the microscope system or produced separately.

[0113] The image acquisition unit 10 is a part of the optical imaging system of the entire vibration measurement system 100, which can be a high-speed camera or a high frame rate camera. The expression related to the acquisition frame rate of the image acquisition unit 100 is: . is the sampling frequency, is the acquisition frame rate, is the calculation time of the control unit, in milliseconds, The delay after calculation, in milliseconds. Corresponds to the highest sampling frequency. The sampling theorem requires that the sampling frequency be at least twice the highest frequency of the measured signal to ensure that the signal frequency is not distorted. Therefore, as the frequency of the vibration signal increases, the corresponding camera frame rate should also increase.

[0114] The measuring unit 20 is an auxiliary unit fixed on the measured object, which is used to calibrate the vibration of the measured object. The measuring surface is provided with a pattern, and when the measured object vibrates in the normal direction, the clearest area of ​​the pattern in the imaging will be offset. The pattern set on the measuring surface can be selected as a periodically changing texture, such as an equally spaced grid, parallel line segments, etc.

[0115] In one embodiment, see Figure 8The vibration measurement system 100 further includes a focusing unit 30, which is used to change the position of the image acquisition unit 10 to adjust the distance between the image acquisition unit 10 and the measuring unit 20. The working principle of the focusing unit 30 is based on the characteristics of the optical imaging system, and the clarity of the image is adjusted by changing the object distance (i.e., the distance from the image acquisition unit to the measuring unit). The focusing unit can be a traditional manual focusing mechanism or an electric focusing mechanism based on a motor.

[0116] In one embodiment, the vibration measurement system 100 also includes an amplification unit 40, which is arranged between the image acquisition unit 10 and the measurement unit 20, and is used to amplify the image of the measurement unit 20, and the magnification of the amplification unit 40 is adjustable. The amplification unit 40 is a component of the optical imaging system, including one or more lenses or reflectors. Its working principle is to increase the magnification of the image by changing the optical path, thereby improving the resolution of the measurement. The amplification unit 40 can be an objective lens in a microscope system. The adjustable magnification means that the system can be flexibly adjusted according to different measurement requirements to adapt to vibrations of different amplitudes. For example, for small vibrations, a higher magnification can be used to capture subtle changes; while for larger vibrations, the magnification can be reduced. On the basis of adjustable magnification, in order to adapt to different magnifications, a plurality of measurement units 20 with different pattern densities can be set. Taking the pattern on the measurement unit 20 as parallel line segments as an example, such as Fig. 9 As shown, the line segment densities of the three measuring units 20 are different, namely 100, 200 and 300 per millimeter.

[0117] In one embodiment, see Figure 8 , the vibration measurement system 100 also includes an angle adjustment unit 50, which is used to adjust the angle between the imaging surface and the measuring surface. The angle adjustment unit 50 can adjust the image sensor in the image acquisition unit 10 manually or electrically, such as rotating it, so that the angle between the imaging surface and the measuring surface changes. After research, it was found that the mapping relationship is a linear relationship, such as z=ax+b. Among them, x represents the first calibration position information in the measurement stage, and z represents the second calibration position information in the calibration stage. a and b are parameters obtained during linear fitting, and a is proportional to the sine of the preset angle. The a in the above expression is the coefficient of the difference between the two first position information, which is equivalent to being related to the sensitivity of vibration detection. The preset angle can be changed by using the angle adjustment unit 50 to change the sensitivity of the vibration measurement system 100.

[0118] In one of the embodiments, the vibration measurement system 100 also includes an orientation adjustment unit 60 for adjusting the shooting direction of the image acquisition unit 10. Traditional electrical vibration measurement methods have high requirements on the installation position of the sensor and can only collect information data in a single direction. It is often necessary to install multiple sensors to capture information data in specific directions (x, y and z), which is inconvenient to install. The shooting direction of the image acquisition unit 10 is parallel to the vibration direction of the object 200 to be measured. Therefore, in order to solve this problem, a orientation adjustment unit 60 is provided in this embodiment, which can change the shooting direction of the image acquisition unit 10, and the measurement unit 20 is decoupled from the entire vibration measurement system 100, and can be flexibly set on the object 200 to be measured, so that the vibration of the object 200 to be measured in any direction can be adapted by adjusting the shooting direction by the orientation adjustment unit 60. For example, Figure 8 If the object to be measured vibrates in the vertical direction, the shooting direction is the vertical direction. If the object to be measured 200 vibrates in the horizontal direction, the vibration measurement system 100 can be set on the side of the object to be measured 200, and the shooting direction can be adjusted to the horizontal direction by the direction adjustment unit 60. The direction adjustment unit 60 can be a pan head, a ball joint, etc., but it is best to have a locking function to ensure the reliability of vibration detection. In addition, if the vibration of the object to be measured is not in a single direction, its vibration can be decomposed, for example, decomposed into three vibration components that are parallel to the x, y, and z axes in space, respectively, and each vibration component corresponds to a set of vibration measurement systems 100 to detect each vibration component separately, and finally the vibration components are summed.

[0119] In one of the embodiments, the vibration measurement system further includes a fill light unit, which is used to fill light for the measurement unit. The fill light unit is used to provide an additional light source for the measurement unit. In many vibration measurement scenarios, the ambient light may be insufficient or unstable, which will affect the image quality and measurement accuracy. The working principle of the fill light unit is to provide a controllable and consistent light source to ensure the quality and stability of image acquisition. This unit may include LED lights, flash lights, or other types of lighting devices. Fill light can not only improve the brightness and contrast of the image, but also enhance the texture or features of the surface of the object being measured through specific lighting techniques (such as structured light), thereby improving the accuracy of vibration measurement.

[0120] In one embodiment, see Figure 8 , Fig.10 and Fig.11 . Fig.10 An exploded diagram of the fill light unit 70 and the measuring unit 20 is shown. Fig.11 The assembly diagram of the fill light unit 70 and the measuring unit 20 is shown. The fill light unit 70 includes a fixing base 71 and a backlight source 72. The fixing base 71 is used to detachably fix the measuring unit 20 on the measured object 200. Fig.10 and Fig.11 The fixed base 71 in the middle fixes the measuring unit 20 detachably through the movable buckle, and the fixed base 71 is used to fix on the measured object 200 to achieve the fixing purpose. A light-transmitting window is provided on the fixed base 71, and the backlight source 72 is used to fill light for the measuring unit 20 through the light-transmitting window. The light-transmitting window can transmit light, and the light emitted by the backlight source 72 passes through the light-transmitting window to illuminate the measuring unit 20 to fill light for it. In addition, the backlight fill light method is a better one, and various other forms of light sources can also be used for fill light in practice.

[0121] The present application provides a vibration measurement device, which is applied to a vibration measurement system. The vibration measurement system includes an image acquisition unit and a measurement unit. The measurement unit is fixed to the object to be measured. There is an angle of a preset angle between the imaging surface of the image acquisition unit and the measurement surface of the measurement unit. The vibration measurement device includes an image acquisition module, a first position information acquisition module, a second position information acquisition module and a vibration information determination module.

[0122] The image acquisition module is used to control the image acquisition unit to acquire multiple continuous measurement images for the measurement unit. The first position information acquisition module is used to determine the first position information corresponding to the clearest area in each measurement image. The first position information reflects the position of the clearest area in the measurement image in the measurement direction of the measurement image, and the measurement direction is the direction in which the object distance corresponding to the pixel point in the image formed by the image acquisition unit changes. The second position information acquisition module is used to obtain the corresponding second position information according to the preset mapping relationship and each first position information. The second position information reflects the object distance corresponding to the clearest area in the measurement image. The vibration information determination module is used to obtain the vibration information of the measured object according to each second position information.

[0123] In one embodiment, the first position information acquisition module is used to determine the definition distribution curve of each measurement image in the measurement direction respectively; and obtain the first position information according to the peak position in the definition distribution curve.

[0124] In one of the embodiments, the vibration measurement system further includes a focusing unit, which is used to change the position of the image acquisition unit to adjust the distance between the image acquisition unit and the measurement unit. The vibration measurement device further includes a calibration module. The calibration module is used to control the focusing unit to adjust the image acquisition unit to a plurality of calibration positions according to a set step length, and control the image acquisition unit to acquire a corresponding calibration image at each calibration position; determine the first calibration position information corresponding to each calibration position according to the calibration image corresponding to each calibration position; the first calibration position information reflects the position of the clearest area in the calibration image corresponding to the calibration position in the measurement direction of the calibration image; determine the second calibration position information corresponding to each calibration position according to the object distance corresponding to the clearest area in the calibration image corresponding to each calibration position; fit the first calibration position information and the second calibration position information corresponding to each calibration position to obtain a mapping relationship.

[0125] In one embodiment, the calibration module is used to control the image acquisition unit to acquire multiple calibration images at each calibration position.

[0126] In one embodiment, the calibration module is used to obtain, for a same calibration position, first calibration position information corresponding to the calibration position according to an average value of positions of clearest areas in each calibration image at the calibration position in a measurement direction of the calibration image.

[0127] In one embodiment, the vibration measurement device further includes a starting point selection module. The starting point selection module is used to determine the upper and lower vibration limits of the measured object in the normal direction; the upper and lower vibration limits are respectively the closest and farthest object distances to the image acquisition unit when the measured object vibrates with the initial position as the starting point; a first measurement threshold is obtained according to the mapping relationship and the upper vibration limit; a second measurement threshold is obtained according to the mapping relationship and the lower vibration limit; a measurement starting point is determined in the image formed by the image acquisition unit, so that the distance from the measurement starting point to the image boundary in the positive direction of the measurement direction is not less than the first measurement threshold, and the distance from the measurement starting point to the image boundary in the reverse direction of the measurement direction is not less than the second measurement threshold; the position of the image acquisition unit is adjusted so that the clearest area in the image formed by the image acquisition unit matches the measurement starting point.

[0128] In one of the embodiments, the starting point selection module is used to adjust the tilt direction of the image acquisition unit to change the measurement direction when the measurement starting point cannot be found; redetermine the mapping relationship corresponding to the new measurement direction, and return to the step of obtaining the first measurement threshold based on the mapping relationship and the vibration upper limit to continue execution.

[0129] In one embodiment, the vibration measurement system further includes an amplification unit, which is arranged between the image acquisition unit and the measurement unit, and is used to amplify the image of the measurement unit, and the amplification factor of the amplification unit is adjustable, and the vibration measurement device further includes a magnification factor selection module. The magnification factor selection module is used to determine the resolution coefficient threshold according to the density of the line segment; and the amplification unit selects a magnification factor with a resolution coefficient not less than the resolution coefficient threshold.

[0130] For the specific limitations of the vibration measuring device, please refer to the limitations of the vibration measuring method above, which will not be repeated here. The various modules in the above-mentioned vibration measuring device can be implemented in whole or in part by software, hardware and a combination thereof. The above-mentioned modules can be embedded in or independent of the processor in the computer device in the form of hardware, or can be stored in the memory in the computer device in the form of software, so that the processor can call and execute the operations corresponding to the above modules. It should be noted that the division of modules in the embodiment of the present application is schematic, which is only a logical function division, and there may be other division methods in actual implementation.

[0131] The present application provides a computer device, comprising one or more processors and a memory, wherein the memory stores computer-readable instructions, and when the computer-readable instructions are executed by the one or more processors, the following are executed: controlling an image acquisition unit to acquire a plurality of continuous measurement images of a measurement unit; respectively determining first position information corresponding to the clearest area in each measurement image; the first position information reflecting the position of the clearest area in the measurement image in the measurement direction of the measurement image, and the measurement direction is the direction in which the object distance corresponding to the pixel point in the image formed by the image acquisition unit changes; obtaining corresponding second position information according to a preset mapping relationship and each first position information; the second position information reflecting the object distance corresponding to the clearest area in the measurement image; and obtaining vibration information of the measured object according to each second position information.

[0132] In one embodiment, the memory stores computer-readable instructions, and when the computer-readable instructions are executed by one or more processors, the steps of the vibration testing method in any of the above embodiments are performed.

[0133] Indicatively, Fig.12 As shown, Fig.12 A schematic diagram of the internal structure of a computer device provided in an embodiment of the present application. Fig.12The computer device 1200 includes a processing component 1202, which further includes one or more processors, and a memory resource represented by a memory 1201 for storing instructions executable by the processing component 1202, such as an application. The application stored in the memory 1201 may include one or more modules, each corresponding to a set of instructions. In addition, the processing component 1202 is configured to execute instructions to perform the steps of the vibration measurement method of any of the above embodiments.

[0134] The computer device 1200 may further include a power supply component 1203 configured to perform power management of the computer device 1200 , a wired or wireless network interface 1204 configured to connect the computer device 1200 to a network, and an input / output (I / O) interface 1205 .

[0135] The present application provides a storage medium, in which computer-readable instructions are stored. When the computer-readable instructions are executed by one or more processors, the one or more processors execute: controlling an image acquisition unit to acquire multiple continuous measurement images of a measurement unit; respectively determining first position information corresponding to the clearest area in each measurement image; the first position information reflects the position of the clearest area in the measurement image in the measurement direction of the measurement image, and the measurement direction is the direction in which the object distance corresponding to the pixel point in the image formed by the image acquisition unit changes; obtaining corresponding second position information according to a preset mapping relationship and each first position information; the second position information reflects the object distance corresponding to the clearest area in the measurement image; and obtaining vibration information of the measured object according to each second position information. The steps of the vibration measurement method in any of the above embodiments.

[0136] In one embodiment, when the computer readable instructions are executed by one or more processors, the one or more processors execute the steps of the vibration testing method in any of the above embodiments.

[0137] Finally, it should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, the elements defined by the sentence "comprise a ..." do not exclude the presence of other identical elements in the process, method, article or device including the elements.

[0138] The various embodiments in this specification are described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The various embodiments can be combined as needed, and the same or similar parts can refer to each other.

[0139] The above description of the disclosed embodiments enables those skilled in the art to implement or use the present application. Various modifications to these embodiments will be apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present application. Therefore, the present application will not be limited to the embodiments shown herein, but will conform to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A vibration measurement method, characterized in that: Applied to a vibration measurement system, the vibration measurement system includes an image acquisition unit and a measurement unit, the measurement unit is fixed to the object to be measured, there is a preset angle between the imaging surface of the image acquisition unit and the measurement surface of the measurement unit, the vibration measurement method includes: Controlling the image acquisition unit to acquire a plurality of continuous measurement images for the measurement unit; respectively determining first position information corresponding to the clearest area in each of the measurement images; the first position information reflects the position of the clearest area in the measurement image in the measurement direction of the measurement image, and the measurement direction is the direction in which the object distance corresponding to the pixel point of the measurement image changes; According to the preset mapping relationship and each of the first position information, corresponding second position information is obtained; the second position information reflects the object distance corresponding to the clearest area in the measurement image; The vibration information of the measured object is obtained according to each of the second position information.

2. The vibration measurement method according to claim 1, characterized in that: The respectively determining the first position information corresponding to the clearest area in each of the measurement images comprises: respectively determining a definition distribution curve of each of the measurement images in the measurement direction; The first position information is obtained according to the peak position in the clarity distribution curve.

3. The vibration measurement method according to claim 1, characterized in that: The vibration measurement system further includes a focusing unit, which is used to change the position of the image acquisition unit to adjust the distance between the image acquisition unit and the measurement unit; Before controlling the image acquisition unit to acquire a plurality of continuous measurement images for the measurement unit, the method further includes: Controlling the focusing unit to adjust the image acquisition unit to a plurality of calibration positions respectively according to a set step length, and controlling the image acquisition unit to acquire a corresponding calibration image at each calibration position; Determine, according to the calibration image corresponding to each calibration position, first calibration position information corresponding to each calibration position; the first calibration position information reflects the position of the clearest area in the calibration image corresponding to the calibration position in the measurement direction of the calibration image; Determine second calibration position information corresponding to each calibration position according to the object distance corresponding to the clearest area in the calibration image corresponding to each calibration position; The mapping relationship is obtained by performing fitting according to the first calibration position information and the second calibration position information corresponding to each calibration position.

4. The vibration measurement method according to claim 3, characterized in that: The step of controlling the image acquisition unit to acquire the corresponding calibration image at each calibration position includes: The image acquisition unit is controlled to acquire a plurality of the calibration images at each calibration position.

5. The vibration measurement method according to claim 4, characterized in that: The determining, according to the calibration images corresponding to the calibration positions, first calibration position information corresponding to the calibration positions includes: For the same calibration position, the first calibration position information corresponding to the calibration position is obtained according to an average value of positions of the clearest areas in the calibration images at the calibration position in the measurement direction of the calibration images.

6. The vibration measurement method according to claim 1, characterized in that: Before controlling the image acquisition unit to acquire a plurality of continuous measurement images for the measurement unit, the method further includes: Determine an upper vibration limit and a lower vibration limit of the measured object in the normal direction; the upper vibration limit and the lower vibration limit are respectively the closest and farthest object distances from the image acquisition unit when the measured object vibrates with the initial position as the starting point; Obtaining a first measurement threshold value according to the mapping relationship and the vibration upper limit; Obtaining a second measurement threshold according to the mapping relationship and the vibration lower limit; Determine a measurement starting point in the image captured by the image acquisition unit, so that a distance from the measurement starting point to an image boundary along a positive direction of the measurement direction is not less than a first measurement threshold, and a distance from the measurement starting point to an image boundary along a reverse direction of the measurement direction is not less than a second measurement threshold; The position of the image acquisition unit is adjusted so that the clearest area in the image captured by the image acquisition unit matches the measurement starting point.

7. The vibration measurement method according to claim 6, characterized in that: Determining the measurement starting point in the imaging plane further comprises: If the measurement starting point cannot be found, adjusting the tilt direction of the image acquisition unit to change the measurement direction; The mapping relationship corresponding to the new measurement direction is re-determined, and the step of obtaining the first measurement threshold value according to the mapping relationship and the vibration upper limit is returned to continue execution.

8. The vibration measurement method according to claim 1, characterized in that: The pattern arranged on the measuring surface is a periodically changing texture.

9. The vibration measurement method according to claim 8, characterized in that: The periodically changing texture is parallel line segments at equal intervals.

10. The vibration measurement method according to claim 9, characterized in that: The vibration measurement system further includes an amplification unit, which is disposed between the image acquisition unit and the measurement unit and is used to amplify the image of the measurement unit, and the amplification factor of the amplification unit is adjustable. Before controlling the image acquisition unit to acquire a plurality of continuous measurement images of the measurement unit, the system further includes: Determining a resolution coefficient threshold according to the density of the line segments; The amplification unit selects and uses an amplification factor whose resolution coefficient is not less than the resolution coefficient threshold.

11. A vibration measurement system, characterized in that: The invention comprises an image acquisition unit, a measuring unit and a control unit, wherein the measuring unit is fixed to the object to be measured, an angle of a preset angle exists between the imaging surface of the image acquisition unit and the measuring surface of the measuring unit, and the control unit is configured to execute the steps of the vibration measurement method according to any one of claims 1 to 10.

12. The vibration measurement system according to claim 11, characterized in that: The device further comprises a focusing unit, wherein the focusing unit is used to change the position of the image acquisition unit to adjust the distance between the image acquisition unit and the measuring unit.

13. The vibration measurement system according to claim 11, characterized in that: It also includes an amplification unit, which is arranged between the image acquisition unit and the measurement unit and is used to amplify the image of the measurement unit. The amplification factor of the amplification unit is adjustable.

14. The vibration measurement system according to claim 11, characterized in that: It also includes an angle adjustment unit for adjusting the angle between the imaging surface and the measuring surface.

15. The vibration measurement system according to claim 11, characterized in that: It also includes a direction adjustment unit for adjusting the shooting direction of the image acquisition unit.

16. The vibration measurement system according to claim 11, characterized in that: The pattern arranged on the measuring surface is a periodically changing texture.

17. The vibration measurement system according to claim 16, characterized in that: The periodically changing texture is parallel line segments at equal intervals.

18. The vibration measurement system according to claim 11, characterized in that: It also includes a fill light unit, which is used to fill light for the measuring unit.

19. The vibration measurement system according to claim 18, characterized in that: The fill light unit includes a fixed base and a backlight source, the fixed base is used to detachably fix the measuring unit on the measured object, a light-transmitting window is provided on the fixed base, and the backlight source is used to fill light for the measuring unit through the light-transmitting window.

20. A vibration measuring device, characterized in that: Applied to a vibration measurement system, the vibration measurement system comprises an image acquisition unit and a measurement unit, the measurement unit is fixed to the object to be measured, there is a preset angle between the imaging surface of the image acquisition unit and the measurement surface of the measurement unit, the vibration measurement device comprises: An image acquisition module, used for controlling the image acquisition unit to acquire a plurality of continuous measurement images for the measurement unit; A first position information acquisition module is used to respectively determine first position information corresponding to the clearest area in each of the measurement images; the first position information reflects the position of the clearest area in the measurement image in the measurement direction of the measurement image, and the measurement direction is the direction in which the object distance corresponding to the pixel point of the measurement image changes; A second position information acquisition module is used to obtain corresponding second position information according to a preset mapping relationship and each of the first position information; the second position information reflects the object distance corresponding to the clearest area in the measurement image; The vibration information determination module is used to obtain the vibration information of the measured object according to each of the second position information.

21. A computer device, characterized in that: The device comprises one or more processors and a memory, wherein the memory stores computer-readable instructions, and when the computer-readable instructions are executed by the one or more processors, the steps of the vibration measurement method according to any one of claims 1 to 10 are executed.

22. A storage medium, characterized in that: The storage medium stores computer-readable instructions, and when the computer-readable instructions are executed by one or more processors, the one or more processors execute the steps of the vibration measurement method according to any one of claims 1 to 10.

Images