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

Abstract

A vibration measurement method, comprising: controlling an image acquisition unit (10) to acquire a plurality of consecutive measurement images of a measurement unit (20) (S202); respectively determining first position information corresponding to the clearest region in each measurement image, wherein the first position information reflects the position of the clearest region in each measurement image in a measurement direction of the measurement image, and the measurement direction is the direction in which object distances corresponding to pixel points in images acquired by the image acquisition unit (10) change (S204); obtaining corresponding second position information on the basis of a preset mapping relationship and each piece of first position information, the second position information reflecting an object distance corresponding to the clearest region in each measurement image (S206); and obtaining vibration information of a measured object (200) on the basis of each piece of second position information (S208). High-precision measurement can be achieved, the method particularly has advantages in the measurement of micro-vibrations, and the requirements for the surface of the measured object (200) are relatively low, thereby facilitating use. Also disclosed are a vibration measurement system (100), a vibration measurement apparatus, a computer device (1200), and a storage device.

Description

A vibration measurement method, system, device, computer equipment and storage medium TECHNICAL FIELD

[0001] The present application relates to the technical field of vibration measurement, and particularly relates to a vibration measurement method, system, device, computer equipment and storage medium. BACKGROUND

[0002] Vibration is one of the most common phenomena in nature, and is also ubiquitous in the field of engineering technology. In particular, micro-vibration generally refers to vibration with a frequency of 2-100 Hz and an amplitude of less than 50 um / s. Indoor equipment operation, noise, outdoor traffic tools, and construction of a plant are all sources of micro-vibration. On the one hand, vibration has a great influence on various measurements, especially in the field of micro-measurement with high precision requirements. On the other hand, in many cases, vibration is harmful, for example, vibration can reduce machining precision and smoothness, and aggravate the wear of structural parts. Therefore, people have developed various anti-vibration devices, which can be generally divided into active anti-vibration and passive anti-vibration, such as an anti-vibration table, an anti-vibration foot pad, and the like. In order to achieve the best anti-vibration effect, no matter what kind of anti-vibration equipment is used, a deep understanding of the nature of the vibration source is needed, such as the type, frequency, amplitude, and the like of the vibration. One of the important methods to understand this information is to measure the vibration. However, in the traditional vibration measurement method, there are problems such as low measurement frequency and precision, high requirements for the surface of the object, and inconvenience of use.

[0003] SUMMARY

[0004] The present application aims to at least solve one of the above technical defects, and particularly aims to solve the defects of low measurement frequency and precision, high requirements for the surface of the object, and inconvenience of use in the prior art.

[0005] In a first aspect, the present application provides a vibration measurement method applied to a vibration measurement system, the vibration measurement system comprising an image acquisition unit and a measurement unit, the measurement unit being fixed to a measured object, and a preset angle being present between an imaging surface of the image acquisition unit and a measurement surface of the measurement unit, the vibration measurement method comprising:

[0006] controlling the image acquisition unit to acquire a plurality of continuous measurement images of the measurement unit;

[0007] determining first position information corresponding to a clearest region in each measurement image, respectively; the first position information reflecting a position of the clearest region in the measurement image in a measurement direction of the measurement image, the measurement direction being a direction in which a distance of a pixel point in the imaging of the image acquisition unit changes;

[0008] obtaining corresponding second position information according to a preset mapping relationship and the first position information; the second position information reflecting a distance of the clearest region in the measurement image.

[0009] According to the second position information of each position, vibration information of the measured object is obtained.

[0010] In one embodiment, the first position information corresponding to the clearest region in each measurement image is determined respectively, comprising:

[0011] The sharpness distribution curve of each measurement image in the measurement direction is determined respectively.

[0012] According to the peak position in the sharpness distribution curve, the first position information is obtained.

[0013] In one embodiment, the vibration measurement system further comprises a focusing unit for changing 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, further comprising:

[0014] The focusing unit is controlled to adjust the image acquisition unit to a plurality of calibration positions respectively according to a set step size, and the image acquisition unit is controlled to acquire corresponding calibration images at each calibration position;

[0015] According to the calibration images corresponding to each calibration position, the first calibration position information corresponding to each calibration position is determined; the first calibration position information reflects the position of the clearest region in the calibration image corresponding to the calibration position in the measurement direction of the calibration image;

[0016] According to the object distance corresponding to the clearest region in the calibration image corresponding to each calibration position, the second calibration position information corresponding to each calibration position is determined;

[0017] According to the first calibration position information and the second calibration position information corresponding to each calibration position, the mapping relationship is obtained.

[0018] In one embodiment, the image acquisition unit is controlled to acquire corresponding calibration images at each calibration position, comprising:

[0019] The image acquisition unit is controlled to acquire a plurality of calibration images at each calibration position respectively.

[0020] In one embodiment, according to the calibration images corresponding to each calibration position, the first calibration position information corresponding to each calibration position is determined, comprising:

[0021] For the same calibration position, according to the average value of the position of the clearest region in the calibration image in the measurement direction of the calibration image under each calibration image at the calibration position, the first calibration position information corresponding to the calibration position is obtained.

[0022] In one embodiment, before the image acquisition unit is controlled to acquire a plurality of continuous measurement images of the measurement unit, further comprising:

[0023] determining 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 the farthest object distance of the measured object from the image acquisition unit when the measured object vibrates from the initial position as a starting point;

[0024] obtaining a first measurement threshold according to the mapping relationship and the upper vibration limit;

[0025] obtaining a second measurement threshold according to the mapping relationship and the lower vibration limit;

[0026] determining a measurement starting point in the imaging of the image acquisition unit, so that the distance of 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 of the measurement starting point to the image boundary in the negative direction of the measurement direction is not less than the second measurement threshold;

[0027] adjusting the position of the image acquisition unit so that the clearest area in the imaging of the image acquisition unit matches the measurement starting point.

[0028] In one of the embodiments, determining the measurement starting point in the imaging surface further includes:

[0029] if the measurement starting point cannot be found, adjusting the tilt direction of the image acquisition unit to change the measurement direction;

[0030] redetermining 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 upper vibration limit.

[0031] In one of the embodiments, the pattern set on the measurement surface is a periodically changing texture.

[0032] In one of the embodiments, the periodically changing texture is an equidistant parallel line segment.

[0033] In one of the embodiments, the vibration measurement system further includes an amplification unit arranged between the image acquisition unit and the measurement unit, for image amplification of the measurement unit, and the amplification multiple of the amplification unit is adjustable, and before the control of the image acquisition unit to acquire multiple continuous measurement images of the measurement unit, the vibration measurement system further includes:

[0034] determining a resolution coefficient threshold according to the density of the line segment;

[0035] selecting an amplification multiple of the amplification unit with a resolution coefficient not less than the resolution coefficient threshold.

[0036] In a second aspect, the present application provides a vibration measurement system, comprising an image acquisition unit, a measurement unit and a control unit, the measurement unit is fixed to a measured object, a preset angle exists between an imaging surface of the image acquisition unit and a measurement surface of the measurement unit, and the control unit is configured to perform the steps of the vibration measurement method in any of the above embodiments.

[0037] In one of the embodiments, the vibration measurement system further comprises a focusing unit, which is configured to change the position of the image acquisition unit to adjust the distance between the image acquisition unit and the measurement unit.

[0038] In one of the embodiments, the vibration measurement system further comprises an amplification unit, which is arranged between the image acquisition unit and the measurement unit and is configured to amplify the image of the measurement unit, and the amplification factor of the amplification unit is adjustable.

[0039] In one of the embodiments, the vibration measurement system further comprises an angle adjustment unit, which is configured to adjust the angle between the imaging surface and the measurement surface.

[0040] In one of the embodiments, the vibration measurement system further comprises a direction adjustment unit, which is configured to adjust the shooting direction of the image acquisition unit.

[0041] In one of the embodiments, the measurement surface is provided with a periodic texture.

[0042] In one of the embodiments, the periodic texture is a parallel line segment with equal intervals.

[0043] In one of the embodiments, the vibration measurement system further comprises a light supplement unit, which is configured to supplement light for the measurement unit.

[0044] In one of the embodiments, the light supplement unit comprises a fixed base and a backlight light source, the fixed base is configured to detachably fix the measurement unit on the measured object, the fixed base is provided with a light transmission window, and the backlight light source is configured to supplement light for the measurement unit through the light transmission window.

[0045] In a third aspect, the present application provides a vibration measurement device, which is 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 a measured object, a preset angle exists between an imaging surface of the image acquisition unit and a measurement surface of the measurement unit, and the vibration measurement device comprises:

[0046] An image acquisition module, which is configured to control the image acquisition unit to acquire a plurality of continuous measurement images of the measurement unit.

[0047] The first position information acquisition module is configured to determine first position information corresponding to the sharpest region in each measurement image respectively; the first position information reflects the position of the sharpest region in the measurement image in a measurement direction of the measurement image, and the measurement direction is a direction in which the object distance corresponding to a pixel point in the imaging of the image acquisition unit changes;

[0048] The second position information acquisition module is configured to obtain corresponding second position information according to a preset mapping relationship and the first position information; the second position information reflects the object distance corresponding to the sharpest region in the measurement image.

[0049] The vibration information determination module is configured to obtain vibration information of the measured object according to the second position information.

[0050] In a fourth aspect, the present application provides a computer device, which comprises one or more processors and a memory, and the memory stores computer readable instructions, and the computer readable instructions are executed by the one or more processors to perform the steps of the vibration measurement method in any of the above embodiments.

[0051] In a fifth aspect, the present application provides a storage medium, which stores computer readable instructions, and the computer readable instructions are executed by one or more processors to make the one or more processors perform the steps of the vibration measurement method in any of the above embodiments.

[0052] From the above technical solutions, it can be seen that the embodiments of the present application have the following advantages:

[0053] The vibration measurement method in the embodiment uses the image acquisition unit to continuously acquire multiple images of the measurement unit fixed on the measured object. Then, the first position information corresponding to the sharpest region in each image is determined. Then, the first position information is converted into second position information through a pre-established mapping relationship. Finally, the vibration characteristics of the measured object are analyzed based on the time sequence of the second position information. This method is a non-contact measurement method, which avoids the interference of traditional contact sensors on the measured object 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, the measurement unit in this measurement method is fixed on the measured object, which is more flexible and has lower requirements for the surface of the measured object, and is more convenient to use. BRIEF DESCRIPTION OF DRAWINGS

[0054] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the following will briefly introduce the drawings needed to be used in the embodiments or prior art description. Obviously, the drawings described below only illustrate some of the embodiments of the present application, and do not illustrate all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative labor are within the scope of protection of the present application.

[0055] FIG. 1 is a schematic diagram of the principle of the vibration measurement method in the present application;

[0056] FIG. 2 is a schematic diagram of the flow of the vibration measurement method provided by an embodiment of the present application;

[0057] FIG. 3 is a schematic diagram of the measurement direction in an embodiment of the present application;

[0058] FIG. 4 is a schematic diagram of the flow of the calibration to obtain the mapping relationship in an embodiment of the present application;

[0059] FIG. 5 is a schematic diagram of the flow of determining the measurement starting point in an embodiment of the present application;

[0060] FIG. 6 is a schematic diagram of selecting the measurement starting point in an embodiment of the present application;

[0061] FIG. 7 is a schematic diagram of selecting the measurement starting point in another embodiment of the present application;

[0062] FIG. 8 is a schematic diagram of the structure of the vibration measurement system provided by an embodiment of the present application;

[0063] FIG. 9 is a schematic diagram of a plurality of different strategy units provided in an embodiment of the present application;

[0064] FIG. 10 is an exploded view of the light supplement unit and the measurement unit in an embodiment of the present application;

[0065] FIG. 11 is an assembly view of the light supplement unit and the measurement unit in an embodiment of the present application;

[0066] FIG. 12 is an internal structure diagram of a computer device provided by an embodiment of the present application. DETAILED DESCRIPTION

[0067] The technical solutions in the embodiments of the present application will be described clearly and completely below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only some of the embodiments of the present application, and not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative labor are within the scope of protection of the present application.

[0068] The application provides a vibration measurement method, which is applied to a vibration measurement system, and the vibration measurement system comprises an image acquisition unit and a measurement unit. The image acquisition unit (for example, a camera) is used to acquire images, and the measurement unit is fixed to an object to be measured, so that when the object to be measured vibrates, the measurement unit vibrates in the same way as the object to be measured, that is, the measurement unit and the object to be measured have the same vibration state. When the image acquisition unit acquires images towards the measurement surface of the measurement unit, the object distance of the measurement surface changes when the measurement surface vibrates in the normal direction. An image sensor (for example, a CMOS image sensor or a CCD image sensor) is arranged in the image acquisition unit, and the measurement surface of the measurement unit is finally imaged on a plane (for example, a plane where a photosensitive element is located) in the image sensor, which is referred to as an imaging plane (also referred to as an image plane). If the object to be measured only vibrates in one direction, one set of measurement unit and image acquisition unit 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 number of decomposed vibration directions are required, and the measurement surface of each measurement unit is perpendicular to the corresponding vibration direction.

[0069] In an optical imaging system, under the condition that the focal length and the image distance are fixed, the object distance and the formed image will form a unimodal function relationship similar to Gaussian distribution, and the peak position corresponds to the focal plane position. Therefore, when the image acquisition unit acquires images of the measurement surface, if the imaging plane 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 sharpness. If there is an angle between the imaging plane and the measurement surface, as shown in FIG. 1, there will be points with different object distances on the measurement surface, resulting in different sharpness of these points in the imaging. The sharpness of each point on the imaging plane along the object distance changing direction will present a unimodal function relationship. In the case that there is an angle between the measurement surface and the imaging plane, when the measurement surface vibrates in the normal direction, the object distance of the measurement surface will change synchronously with the amplitude of the vibration, so that the image of the unimodal function will be translated as a whole in its coordinate system, and the peak position represents the position of the whole function image, so the peak position can be observed to change with the vibration of the measurement surface in the normal direction. Therefore, the application establishes a relationship between the peak position and the vibration of the object to be measured based on this principle, and determines the vibration of the object to be measured by detecting the change of the peak position. The application sets a preset angle between the imaging plane of the image acquisition unit and the measurement surface of the measurement unit. In order to facilitate measurement in actual operation, the preset angle can be realized by controlling the inclination of the imaging plane. Of course, it can also be realized by changing the angle of the measurement surface. Specifically, please refer to FIG. 2, the vibration measurement method comprises steps S202 to S208.

[0070] S202, control the image acquisition unit to acquire a plurality of continuous measurement images of the measurement unit.

[0071] It can be understood that the measurement image is an image obtained by the image acquisition unit shooting towards the measurement surface of the measurement unit. The plurality of measurement images herein is at least two. The acquisition of the plurality of measurement images is because the vibration is a dynamic process, and a single image can only reflect the position of the measurement surface at a certain time, and the change of the position can be obtained according to the plurality of continuous images, so as to analyze the vibration of the measured object. In addition, in order to better acquire the vibration of the measured object, attention should be paid to the selection of the frame rate of the image acquisition unit. With the increase of the vibration frequency of the measured object, the frame rate of the selected image acquisition unit should also be increased. Therefore, in some cases, the image acquisition unit needs to use a high-speed camera or a high-frame-rate camera.

[0072] S204, respectively determine the first position information corresponding to the clearest region in each measurement image. The first position information reflects the position of the clearest region in the measurement image in the measurement direction of the measurement image. The measurement direction is the direction in which the object distance corresponding to the pixel point in the imaging of the image acquisition unit changes.

[0073] It can be understood that in the optical imaging system, due to the existence of the included angle between the imaging surface and the measurement surface, the object distance of different positions on the measurement surface will be different, which leads to the difference in the definition of the corresponding region of each point on the measurement surface in the measurement image. The clearest region refers to the part with the highest definition in the image. The pixel points obtained based on the measurement surface in the measurement image have a one-to-one correspondence with each region of the measurement surface. Due to the existence of the preset angle, the object distance of these regions will change, and in the imaging of the image acquisition unit, the object distance corresponding to each pixel point along the measurement direction will change the fastest. Therefore, the definition of the measurement direction is the direction in which the object distance corresponding to the pixel point in the imaging of the image acquisition unit changes. The inclination angle shown in FIG. 1 is viewed from the front, and the short sides of the imaging surface and the measurement surface are parallel to each other, and the long sides have an included angle of the preset angle. Therefore, the object distance corresponding to each pixel point of the formed image changes the fastest along the long side of the formed image, as shown in FIG. 3.

[0074] The object distance of each point in the measurement direction is different, so the definition of the corresponding imaging is also different. In the measurement stage, the position of the part with the highest definition 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 region in different measurement images will change, which is the key information for analyzing the vibration. This analysis process needs to be performed separately for each measurement image to obtain a series of first position information changing with time.

[0075] If the position is expressed by coordinates, an origin can be selected in the measurement direction, and a clearness distribution curve of the measurement stage can be formed by taking the distance between each point and the origin in the measurement direction as the horizontal axis and the clearness corresponding to the imaging of each point as the vertical axis. Specifically, the clearness distribution curve can be a plurality of sampling points selected at a preset interval between the boundaries at both ends of the measurement direction. The distance between each sampling point and the origin in the measurement direction is determined as the horizontal coordinate, and the clearness corresponding to each sampling point is determined as the vertical coordinate. Then, the selected unimodal function curve is fitted to the coordinate pairs of the sampling points (i.e., the coordinate pairs composed of the corresponding horizontal coordinates and vertical coordinates), and the clearness distribution curve is obtained. 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 clearness distribution curve of the measurement stage is the first position information. In addition, there are many ways to express the clearness of an image in the image field, such as the Brenner gradient, the Tenegrad gradient, the Laplace gradient, the central difference operator, etc. The specific way to express the clearness of an image can be selected according to actual needs.

[0076] In S206, the corresponding second position information is obtained according to the preset mapping relationship and the first position information. The second position information reflects the object distance corresponding to the sharpest region in the measurement image.

[0077] It can be understood that through research and analysis, it is found that when there is an included angle between the imaging surface and the measurement surface, if the measurement surface changes 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 object distance change of the measurement surface, which can be fitted according to a certain amount of data. Therefore, before starting the measurement, the entire system can be calibrated first to fit the mapping relationship corresponding to the current system configuration (such as the selection of the preset angle, the tilt direction, etc.).

[0078] In the measurement stage, the second position information is defined as reflecting the object distance corresponding to the sharpest region in the measurement image. The position on the measurement surface forms the sharpest image in the entire image, and the second position information reflects the object distance corresponding to the position. This step needs to convert the first position information obtained based on each measurement image into the corresponding second position information. Since the measurement surface is perpendicular to one vibration direction of the measured object, 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 a plurality of continuous time points. After the mapping relationship is determined, the first position information can be input into the mapping relationship to obtain the corresponding second position information.

[0079] In S208, the vibration information of the measured object is obtained according to the second position information.

[0080] It can be understood that the second position information reflects the change of the object distance of the measurement 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. The 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 performing Fourier transform on the second position information or by calculating the time interval between adjacent peaks. The vibration waveform can be directly represented by the change curve of the second position information over time. In addition, it can also include more detailed characteristics such as the phase information and harmonic components of the vibration. In actual analysis, signal processing techniques may be applied to improve the quality and reliability of the data. For example, filtering techniques can be used to remove noise, interpolation techniques can be used to improve time resolution, or statistical methods can be used to improve the stability and repeatability of the measurement.

[0081] The vibration measurement method in this embodiment uses the image acquisition unit to continuously acquire multiple images of the measurement unit fixed on the measured object. Then, the first position information corresponding to the clearest area in each image is determined. Then, the first position information is converted to the second position information through the pre-established mapping relationship. Finally, based on the time series of the second position information, the vibration characteristics of the measured object are analyzed. This method is a non-contact measurement method that avoids the interference that traditional contact sensors may cause to the measured object, and can more accurately reflect the true vibration state of the object. Secondly, through optical imaging and image processing techniques, this method can achieve high-precision measurement, especially in the measurement of small vibrations. In addition, the way the measurement unit is fixed on the measured object in this measurement method is relatively free, and the surface requirements for the measured object are relatively low, making it more convenient to use.

[0082] In one embodiment, the vibration measurement system further includes a focusing unit for changing the position of the image acquisition unit to adjust the object distance. Please refer to FIG. 4, before controlling the image acquisition unit to acquire multiple continuous measurement images of the measurement unit, steps S402 to S408 are further included.

[0083] S402, control the focusing unit to adjust the image acquisition unit to multiple calibration positions according to the set step length, and control the image acquisition unit to acquire corresponding calibration images at each calibration position.

[0084] 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 the vibration detection, the calibration of the mapping relationship needs to be performed. The calibration positions refer to different positions of the image acquisition unit relative to the measurement unit in the calibration stage, and the object distance corresponding to each calibration position is different, which will cause the peak position of the sharpness distribution curve corresponding to each calibration position to change. In the calibration stage, 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 the image of the measurement unit at each calibration position to obtain the 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 set step length can be adjusted as needed. A smaller set step length can obtain more data and higher fitting accuracy. A longer set step length can improve the fitting efficiency. The set step length can remain fixed during the entire calibration stage or can change during the calibration process.

[0085] S404, according to the calibration image corresponding to each calibration position, determine the first calibration position information corresponding to each calibration position. The first calibration position information reflects the position of the sharpest region in the calibration image in the measurement direction of the calibration image corresponding to the calibration position.

[0086] It can be understood that the first calibration position information is similar to the definition of the first position information, and the difference lies in that the former is a concept in the calibration stage, and the latter is a concept in the measurement stage. In the calibration image corresponding to each calibration position, due to the angle between the imaging surface and the measurement surface, the sharpness of the corresponding region of each point on the measurement surface in the calibration image is different. The sharpest region refers to the part with the highest sharpness in the image. In the calibration stage, the corresponding position of the part with the highest sharpness in the measurement direction of the calibration image is the first calibration position information.

[0087] If only one calibration image is acquired at each calibration position, the position of the sharpest region in the measurement direction of the calibration image is directly taken as the first calibration position information. If multiple calibration images are acquired at each calibration position, for the same calibration position, the positions of the sharpest regions in the measurement direction of the calibration images under the calibration position are determined respectively, and then the average value of these positions is obtained 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.

[0088] In addition, the corresponding position of the clearest region in the calibration image in the measurement direction of the measurement surface is determined in the calibration stage, which is similar to the above description. That is, if the position is expressed by coordinates, an origin can be selected in the measurement direction, and the distance between each point and the origin in the measurement direction is taken as the horizontal axis, and the sharpness corresponding to the imaging of each point is taken as the vertical axis, to form the sharpness distribution curve in the calibration stage. The horizontal coordinate corresponding to the peak position of the sharpness distribution curve in the calibration stage is the position of the clearest region in the calibration image in the measurement direction of the calibration image. Specifically, the sharpness distribution curve can be a plurality of sampling points selected at a preset interval between the boundaries at both ends of the measurement direction. The distance between each sampling point and the origin in the measurement direction is taken as the horizontal coordinate, and the vertical coordinate of the sharpness corresponding to each sampling point. Then, the selected unimodal function curve is used to fit the coordinate pairs of the sampling points (i.e., the coordinate pairs composed of the corresponding horizontal coordinates and vertical coordinates). The sharpness distribution curve is obtained. 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 sharpness distribution curve in the measurement stage is the first position information. In addition, there are many ways to represent the sharpness of an image in the image field, such as the Brenner gradient, the Tenegrad gradient, the Laplace gradient, the central difference operator, etc. The specific selection of which way to represent the sharpness of an image can be selected according to actual needs. The image sharpness expression method used in the measurement stage and the calibration stage should be consistent.

[0089] S406, determining the second calibration position information corresponding to each calibration position according to the object distance corresponding to the clearest region in the calibration image corresponding to each calibration position.

[0090] 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, the object distance corresponding to the position of the clearest region imaged on the measurement surface when the image acquisition unit is at each calibration position can also be measured. The measurement means can refer to mature technologies in the fields of optical imaging and microscopic imaging. This step can directly use the object distance corresponding to the clearest region in the calibration image corresponding to each calibration position.

[0091] S408, fitting the first calibration position information and the second calibration position information corresponding to each calibration position to obtain the mapping relationship.

[0092] 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. It is found through research that there is generally a linear relationship between the first calibration position information and the second calibration position information, such as z=ax+b. Wherein, 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 directly proportional to the sine of the preset angle. If a magnification unit is arranged between the measurement unit and the image acquisition unit to magnify the imaging, a is also inversely proportional to the square of the magnification of the magnification unit.

[0093] In one of the embodiments, before the image acquisition unit acquires multiple continuous measurement images of the measurement unit, please refer to FIG. 5, it further includes steps S502 to S510.

[0094] S502, determine the vibration upper limit and the vibration lower limit of the measured object in the normal direction. The vibration upper limit and the vibration lower limit are respectively the closest and the farthest object distance of the measured object from the image acquisition unit when the measured object vibrates from the initial position as the starting point.

[0095] 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 changes the object distance, so that the clearest area in the 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 cannot be detected, thereby affecting the vibration measurement. Therefore, reasonably selecting the position of the clearest area in the measurement image at the start of the measurement (i.e. the measurement starting point) can reasonably utilize the range of the imaging. For some measurement scenes, the vibration amplitude of the measured object can be predicted, estimated or analyzed in advance, and in these scenes, the vibration upper limit and the vibration lower limit can be determined respectively to assist the selection of the measurement starting point.

[0096] S504, obtain the first measurement threshold according to the mapping relationship and the vibration upper limit.

[0097] S506, obtain the second measurement threshold according to the mapping relationship and the vibration lower limit.

[0098] It can be understood that the mapping relationship is established in the calibration process, which describes the mapping relationship between the position in the measurement direction in the image and the object distance. The definition of the orientation of the most clear region moving along the measurement direction when the measured object approaches the image acquisition unit is the positive direction, and the orientation of the most clear region moving along the measurement direction when the measured object moves away from the image acquisition unit is the negative direction. First, the position information of the most clear region in the measurement direction when the measured object is located at the initial position is determined as the reference position information.

[0099] When the measured object moves to the upper limit of vibration, the object distance is the smallest, and the most clear region also moves to an extreme position along 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 limit deviation of the most clear region in the image when vibrating upward from the initial position of vibration.

[0100] Similarly, when the measured object moves to the lower limit of vibration, the object distance is the largest, and the most clear region also moves to another extreme position along the negative 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 limit deviation of the most clear region in the image when vibrating downward from the initial position of vibration.

[0101] S508, determining 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 along 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 along the negative direction of the measurement direction is not less than the second measurement threshold.

[0102] It can be understood that after the first measurement threshold and the second measurement threshold are determined, the appropriate 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 most clear region when the measurement starts. When the measured object approaches the image acquisition unit, the most clear region will move along the positive direction of the measurement direction in the image, and the deviation of the movement will not exceed the first measurement threshold. Therefore, in order to ensure that the most clear region will not move out of the boundary of the image, it is necessary to ensure that the distance from the measurement starting point to the image boundary along the positive direction of the measurement direction is not less than the first measurement threshold. When the measured object moves away from the image acquisition unit, the most clear region will move along the negative direction of the measurement direction in the image, and the deviation of the movement will not exceed the second measurement threshold. Therefore, in order to ensure that the most clear region will not move out of the boundary of the image, it is necessary to ensure that the distance from the measurement starting point to the image boundary along the negative direction of the measurement direction is not less than the second measurement threshold.

[0103] It is worth mentioning that the vibration of some vibration scenes is not symmetrical, i.e. the offset between the vibration upper limit and the initial position and the offset between the vibration lower limit and the initial position can not be the same. Therefore, the measurement starting point does not necessarily need to be located at the center of the entire image. For example, as shown in FIG. 6, in the imaging as shown in FIG. 3, if the offset between the vibration upper limit and the initial position is greater than the offset between the vibration lower limit and the initial position, it will result in that the first measurement threshold is greater than the second measurement threshold. If the first measurement threshold is greater than half of the long side of the image, placing the measurement starting point at the midpoint of the measurement direction will result in that the distance from the measurement starting point to the positive direction of the measurement direction to the image boundary is less than the second measurement threshold. At this time, it is necessary to select the measurement starting point at the left side as shown in FIG. 6.

[0104] S510, adjusting the position of the image acquisition unit so that the clearest region in the image formed by the image acquisition unit matches the measurement starting point.

[0105] It can be understood that the clearest region usually corresponds to the current position of the measured object, and aligning it with the measurement starting point can ensure that the entire vibration process can be effectively captured. The adjustment process can involve physical movement of the image acquisition unit (for example, adjusting the object distance through the focusing unit) or adjusting the position of the measurement unit on the mounting seat. This adjustment process can require multiple iterations, and after each adjustment, the image needs to be re-acquired and the clarity distribution needs to be analyzed until the best match is achieved.

[0106] In one embodiment, 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. Redetermine the mapping relationship corresponding to the new measurement direction, and continue to execute the step of obtaining the first measurement threshold according to the mapping relationship and the vibration upper limit.

[0107] It can be understood that in actual operation, there can also be a situation where any point in the measurement direction of the image cannot meet the requirements. For example, as shown in the upper part of FIG. 7, neither of the two boundaries of the measurement starting point in the measurement direction can meet the requirements. At this time, 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 points in the image formed by the image acquisition unit changes, and when the tilt direction of the imaging plane changes, the measurement direction will change. The tilt direction of the imaging plane can be changed by rotating in space (for example, rotating around the center).

[0108] As the imaging surface in FIG. 1 is rotated counterclockwise, the measurement direction also changes until it changes to the case shown in FIG. 7 below, and the measurement starting point can be found. However, it is worth mentioning that since the calculation of some clarity needs to refer to multiple pixel points perpendicular to the measurement direction, in the case shown in FIG. 7 above, the number of pixel points distributed at each position in the measurement direction is the same, and the quality of the obtained clarity distribution curve is better. However, in the case shown in FIG. 7 below, there is a problem of fewer pixel points corresponding to both ends, and the quality of the obtained clarity distribution curve will be affected. Therefore, when selecting the measurement direction, attention should be paid to whether the number of available pixel points at each position is higher than the lower limit that guarantees the quality of the curve.

[0109] After the measurement direction is changed, the current mapping relationship no longer matches the new measurement direction, and needs to be recalibrated according to the flow in FIG. 4 to obtain a mapping relationship that matches the new measurement direction. After obtaining the new mapping relationship, return to step S504 for continuous execution, and find a suitable measurement starting point after the measurement direction is changed.

[0110] In one embodiment, the measurement surface is provided with a pattern, and when the normal direction of the measured object vibrates, the clearest area in the imaging of the pattern will shift. This is because the application needs to rely on the vibration of the measured object to detect the position change of the clearest area. If no pattern is set or the imaging of the pattern is completely consistent when the measured object vibrates, it is impossible to implement the scheme in the application. In a specific embodiment, on the basis of meeting the above requirements, the pattern provided on the measurement surface can be a periodically changing texture, such as an equidistant grid, parallel line segments, etc.

[0111] In one embodiment, the vibration measurement system further includes an amplification unit arranged between the image acquisition unit and the measurement unit, for image amplification of the measurement unit, and the amplification factor of the amplification unit is adjustable. In order to detect slight vibration, the size of the pattern provided on the measurement surface also needs to be reduced. In order for the image acquisition unit to be able to distinguish the pattern, the amplification unit needs to be introduced, and an appropriate amplification factor needs to be selected for the amplification unit. Therefore, before controlling the image acquisition unit to acquire multiple continuous measurement images of the measurement unit, it further includes: determining a resolution coefficient threshold according to the density of the line segments. The amplification unit selects an amplification factor with a resolution coefficient not less than the resolution coefficient threshold.

[0112] It can be understood that the resolution coefficient is an index for measuring the resolution capability of the optical system, which is related to the minimum detail size that the system can distinguish. The resolution coefficient threshold is the minimum resolution capability requirement set according to specific measurement requirements. In the process of determining the resolution coefficient 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, which is usually represented by the number of line segments per unit length. The higher the line segment density, the greater the required resolution coefficient to ensure that the system can clearly distinguish each line segment. The system will select a magnification factor that is not less than the resolution coefficient threshold, which ensures that the system can clearly distinguish the line segment texture on the measurement surface. In a specific embodiment, the resolution coefficient can be selected as the numerical aperture. The resolution coefficient 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 coefficient threshold.

[0113] The present application provides a vibration measurement system 100. Please refer to FIG. 8, which includes an image acquisition unit 10, a measurement unit 20, and a control unit (not shown in the figure). The measurement unit 20 is fixed to the measured object 200, and there is a preset angle between the imaging surface of the image acquisition unit 10 and the measurement surface of the measurement unit 20. 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 a microscopy system or can be additionally produced.

[0114] The image acquisition unit 10 is 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: fs≥fN+Tc+Td. fs is the sampling frequency, fN is the acquisition frame rate, Tc is the calculation time of the control unit, which is in milliseconds, and Td is the delay after calculation, which is in milliseconds. Corresponding 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 be increased.

[0115] The measurement unit 20 is a auxiliary unit fixed on the measured object, which is used to calibrate the vibration condition of the measured object. The measurement 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 shift. The pattern provided on the measurement surface can be selected as a periodically varying texture. For example, equally spaced grid, parallel line segment, etc.

[0116] In one embodiment, as shown in FIG. 8, the vibration measurement system 100 further comprises a focusing unit 30 for changing the position of the image acquisition unit 10 to adjust the distance between the image acquisition unit 10 and the measurement unit 20. The working principle of the focusing unit 30 is based on the characteristics of the optical imaging system, which adjusts the sharpness of the image by changing the object distance (i.e. the distance from the image acquisition unit to the measurement unit). The focusing unit can be a traditional manual focusing mechanism or an electric motor-based electric focusing mechanism.

[0117] In one embodiment, the vibration measurement system 100 further comprises a magnification unit 40 arranged between the image acquisition unit 10 and the measurement unit 20 for image magnification of the measurement unit 20, and the magnification of the magnification unit 40 is adjustable. The magnification unit 40 is a component of the optical imaging system, which includes one or more lenses or mirrors. Its working principle is to increase the magnification of the image by changing the optical path, thereby improving the resolution of the measurement. The magnification 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, and is suitable for different amplitude vibrations. 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, multiple measurement units 20 with different pattern densities can be provided. For example, as shown in FIG. 9, the line densities of the three measurement units 20 are different, which are 100, 200 and 300 lines per millimeter.

[0118] In one embodiment, as shown in FIG. 8, the vibration measurement system 100 further comprises an angle adjustment unit 50 for adjusting the included angle between the imaging surface and the measurement surface. The angle adjustment unit 50 can adjust the image sensor in the image acquisition unit 10 by manual or electric means, such as rotation, to change the included angle between the imaging surface and the measurement surface. It is found through research that the mapping relationship is a linear relationship, such as z = ax + b. Wherein, 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 when 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 the sensitivity of the vibration detection, and the preset angle can be changed by using the angle adjustment unit 50 to change the sensitivity of the vibration measurement system 100.

[0119] In one embodiment, the vibration measurement system 100 further comprises a direction adjustment unit 60 for adjusting the shooting direction of the image acquisition unit 10. Traditional electrical vibration measurement methods have high requirements for sensor installation location and can only collect information data in a single direction, often requiring the installation of 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 measured object 200, therefore, to solve this problem, the embodiment is provided with the direction adjustment unit 60, 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, which can be flexibly arranged on the measured object 200, so that the measured object 200 can be adapted by adjusting the shooting direction through the direction adjustment unit 60 when vibrating in any direction. For example, in FIG. 8, the measured object vibrates in the vertical direction, and the shooting direction is the vertical direction. If the measured object 200 vibrates in the horizontal direction, the vibration measurement system 100 can be arranged on the side of the measured object 200, and the shooting direction can be adjusted to the horizontal direction through the direction adjustment unit 60. The direction adjustment unit 60 can be a pan-tilt head, a spherical joint, etc., but preferably has a locking function to ensure the reliability of vibration detection. In addition, if the vibration of the measured object is not in a single direction, it can be decomposed, for example, into three vibration components respectively parallel to the x, y, and z axes in space, each vibration component corresponding to a set of vibration measurement systems 100 to detect each vibration component, and finally the vibration components are summed.

[0120] In one embodiment, the vibration measurement system further comprises a light supplement unit for supplementing light for the measurement unit. The light supplement unit is used to provide additional light sources 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 principle of the light supplement 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, flashlights or other types of lighting devices. Light supplementation not only improves the brightness and contrast of the image, but also enhances the texture or features of the surface of the measured object through specific lighting techniques (such as structured light), thereby improving the accuracy of vibration measurement.

[0121] In one of the embodiments, please refer to FIG. 8, FIG. 10 and FIG. 11. FIG. 10 shows an exploded view of the light supplement unit 70 and the measurement unit 20, and FIG. 11 shows an assembly view of the light supplement unit 70 and the measurement unit 20. The light supplement unit 70 includes a fixing base 71 and a backlight light source 72. The fixing base 71 is used to detachably fix the measurement unit 20 on the measured object 200. In FIG. 10 and FIG. 11, the fixing base 71 detachably fixes the measurement unit 20 through a movable buckle. The fixing base 71 is used to be fixed on the measured object 200 to achieve the fixing purpose. The fixing base 71 is provided with a light transmission window. The backlight light source 72 is used to supplement light for the measurement unit 20 through the light transmission window. The light transmission window can transmit light. The light emitted by the backlight light source 72 passes through the light transmission window to illuminate the measurement unit 20 to supplement light for it. In addition, the backlight light supplement method is a good one. In practice, other various forms of light sources can also be used to supplement light.

[0122] The application provides a vibration measurement device applied to a vibration measurement system. The vibration measurement system includes an image acquisition unit and a measurement unit. The measurement unit is fixed on a measured object. There is a preset angle between an imaging surface of the image acquisition unit and a 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.

[0123] The image acquisition module is used to control the image acquisition unit to acquire a plurality of continuous measurement images of the measurement unit. The first position information acquisition module is used to determine first position information corresponding to a clearest area in each measurement image respectively. The first position information reflects a position of the clearest area in the measurement image in a measurement direction of the measurement image. The measurement direction is a direction in which a pixel point corresponding to an object distance in imaging of the image acquisition unit changes. The second position information acquisition module is used to obtain corresponding second position information according to a preset mapping relationship and the first position information. The second position information reflects an object distance corresponding to the clearest area in the measurement image. The vibration information determination module is used to obtain vibration information of the measured object according to the second position information.

[0124] In one of the embodiments, the first position information acquisition module is used to determine a sharpness distribution curve of each measurement image in the measurement direction respectively. The first position information is obtained according to a peak position in the sharpness distribution curve.

[0125] In one of the embodiments, the vibration measurement system further comprises a focusing unit, which is configured 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 comprises a calibration module. The calibration module is configured to control the focusing unit to adjust the image acquisition unit to a plurality of calibration positions respectively according to a set step length, and control the image acquisition unit to acquire a corresponding calibration image at each calibration position; 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 region in the calibration image in the measurement direction of the calibration image corresponding to the calibration position; determine second calibration position information corresponding to each calibration position according to the object distance corresponding to the clearest region in the calibration image corresponding to each calibration position; and fit the first calibration position information and the second calibration position information corresponding to each calibration position to obtain a mapping relationship.

[0126] In one of the embodiments, the calibration module is configured to control the image acquisition unit to acquire a plurality of calibration images at each calibration position respectively.

[0127] In one of the embodiments, the calibration module is configured to obtain the first calibration position information corresponding to the same calibration position according to the average value of the positions of the clearest regions in the calibration images at the calibration position in the measurement direction of the calibration image.

[0128] In one of the embodiments, the vibration measurement device further comprises a starting point selection module. The starting point selection module is configured to determine the upper limit and the lower limit of the vibration of the measured object in the normal direction; the upper limit and the lower limit of the vibration are respectively the closest and the farthest object distance when the measured object vibrates with the initial position as the starting point; obtain a first measurement threshold according to the mapping relationship and the upper limit of the vibration; obtain a second measurement threshold according to the mapping relationship and the lower limit of the vibration; 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 the 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 the second measurement threshold; and adjust the position of the image acquisition unit so that the clearest region in the image formed by the image acquisition unit matches the measurement starting point.

[0129] In one of the embodiments, the starting point selection module is configured to adjust the tilt direction of the image acquisition unit to change the measurement direction in the case that the measurement starting point cannot be found; re-determine the mapping relationship corresponding to the new measurement direction, and continue to execute the step of obtaining the first measurement threshold according to the mapping relationship and the upper limit of the vibration.

[0130] In one of the embodiments, the vibration measurement system further comprises an amplification unit arranged between the image acquisition unit and the measurement unit, for image amplification of the measurement unit, and the amplification factor of the amplification unit is adjustable, and the vibration measurement device further comprises an amplification factor selection module. The amplification factor selection module is configured to determine a resolution coefficient threshold according to the density of the line segment, and the amplification unit is configured to select an amplification factor with a resolution coefficient not less than the resolution coefficient threshold.

[0131] The specific limitations of the vibration measurement device can refer to the limitations of the vibration measurement method described above, and will not be repeated here. Each module in the vibration measurement device described above can be implemented by software, hardware, and combinations thereof, in whole or in part. The above modules can be embedded in or independent of the processor in the computer device in hardware form, or can be stored in the memory in the computer device in software form, so that the processor can call and execute the operations corresponding to each module. It should be noted that the division of the modules in the embodiments of the present application is illustrative, and is only a logical functional division. In actual implementation, there can be another division manner.

[0132] The present application provides a computer device, comprising one or more processors, and a memory, wherein the memory stores computer readable instructions, and the computer readable instructions are executed by the one or more processors to perform: controlling an image acquisition unit to acquire a plurality of continuous measurement images of a measurement unit; determining first position information corresponding to a clearest region in each measurement image, respectively; the first position information reflects the position of the clearest region in the measurement image in a measurement direction of the measurement image, and the measurement direction is a direction in which the object distance corresponding to a pixel point in the image formed by the image acquisition unit changes; obtaining corresponding second position information according to a preset mapping relationship and the first position information; the second position information reflects the object distance corresponding to the clearest region in the measurement image; and obtaining vibration information of the measured object according to the second position information, wherein the steps of the vibration measurement method in any one of the embodiments described above are performed.

[0133] In one of the embodiments, the memory stores computer readable instructions, and the computer readable instructions are executed by the one or more processors to perform the steps of the vibration test method in any one of the embodiments described above.

[0134] Illustratively, as shown in FIG. 12, FIG. 12 is a schematic diagram of an internal structure of a computer device according to an embodiment of the present application. Referring to FIG. 12, the 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, such as an application program, executable by the processing component 1202. The application program stored in the memory 1201 can include one or more than one, each corresponding to a module of instructions. In addition, the processing component 1202 is configured to execute the instructions to perform the steps of the vibration measurement method of any of the embodiments described above.

[0135] The computer device 1200 can 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.

[0136] The present application provides a storage medium, the storage medium storing computer readable instructions, the computer readable instructions being executed by one or more processors to cause the one or more processors to perform: controlling an image acquisition unit to acquire a plurality of continuous measurement images of a measurement unit; determining first position information corresponding to a sharpest region in each measurement image, respectively; the first position information reflecting a position of the sharpest region in the measurement image in a measurement direction of the measurement image, the measurement direction being a direction in which a distance of a pixel point in an image formed by the image acquisition unit changes; obtaining corresponding second position information according to a preset mapping relationship and the first position information; the second position information reflecting a distance of the sharpest region in the measurement image; and obtaining vibration information of a measured object according to the second position information.

[0137] In one embodiment, the computer readable instructions are executed by one or more processors to cause the one or more processors to perform the steps of the vibration test method in any of the embodiments described above.

[0138] Finally, it should be noted that the terms "first", "second", and the like, herein do not denote any order, quantity, combination, or importance, but rather are used to distinguish one element from another, and are not intended to denote the presence of any such actual relationship or order. Moreover, the terms "include", "have", or any other variant thereof are intended to encompass non-exclusive inclusions, such that processes, methods, articles, or apparatuses that comprise a list of elements are not required to comprise only those elements in the list, but can include other elements not expressly listed, or also include elements inherent in such processes, methods, articles, or apparatuses. Without additional restrictions, an element preceded by "comprises... a" does not exclude the existence of additional identical elements in the process, method, article, or apparatus that comprises the stated element.

[0139] The various embodiments in the specification are described in progressive order with each embodiment building on one or more of the previous embodiments, however the order of the embodiments described is not intended to be construed as a requirement or limitation for these embodiments. Any one or more of the embodiments described with reference to a particular set of one or more other embodiments are optionally employable together with one or more other embodiments and / or in any appropriate combination.

[0140] The above description of disclosed embodiments is intended to enable those skilled in the art to make or use the application. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the generic principles defined herein can be applied to other embodiments without departing from the spirit or scope of the application. Thus, the present application is not intended to be limited to the embodiments shown herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A method of measuring vibrations, characterized by, The application is 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 a measured object, there is a preset angle between an imaging surface of the image acquisition unit and a measurement surface of the measurement unit, the vibration measurement method comprises: controlling the image acquisition unit to acquire multiple continuous measurement images of the measurement unit; determining 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 a 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; 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; obtaining vibration information of the measured object according to each second position information.

2. The vibration measurement method according to claim 1, characterized by, The method further comprises: determining a clarity distribution curve of each measurement image in the measurement direction respectively; obtaining the first position information according to the peak position in the clarity distribution curve.

3. The vibration measurement method according to claim 1, characterized by, The vibration measurement system further comprises a focusing unit, the focusing unit is used for changing the position of the image acquisition unit to adjust the distance between the image acquisition unit and the measurement unit; Before the control of the image acquisition unit to acquire multiple continuous measurement images of the measurement unit, the method further comprises: controlling the focusing unit to adjust the image acquisition unit to multiple calibration positions respectively according to a set step length, and controlling the image acquisition unit to acquire corresponding calibration images at each calibration position; determining first calibration position information corresponding to each calibration position according to the corresponding calibration image of 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; 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; fitting the first calibration position information and the second calibration position information corresponding to each calibration position to obtain the mapping relationship.

4. The vibration measurement method according to claim 3, characterized by, The method further comprises: controlling the image acquisition unit to acquire multiple calibration images at each calibration position respectively.

5. The vibration measurement method according to claim 4, characterized by, The method further comprises: for the same calibration position, obtaining the first calibration position information corresponding to the calibration position according to the average value of the positions of the clearest area in each calibration image in the measurement direction of the calibration image at the calibration position.

6. The vibration measurement method according to claim 1, characterized by, The method further comprises: determining 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 being respectively the closest and the farthest distance from the image acquisition unit when the measured object vibrates from the initial position as a starting point; obtaining a first measurement threshold according to the mapping relationship and the upper vibration limit; obtaining a second measurement threshold according to the mapping relationship and the lower vibration limit; determining a measurement starting point in the imaging of 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 negative direction of the measurement direction is not less than the second measurement threshold; adjusting the position of the image acquisition unit so that the clearest area in the imaging of the image acquisition unit matches the measurement starting point.

7. The vibration measurement method according to claim 6, characterized by, The step of determining the measurement starting point in the imaging surface further comprises: if the measurement starting point cannot be found, adjusting the tilt direction of the image acquisition unit to change the measurement direction; redetermining 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 upper vibration limit. The pattern provided on the measurement surface is a periodically changing texture.

8. The vibration measurement method according to claim 1, characterized by, The periodically changing texture is an equally spaced parallel line segment.

9. The vibration measurement method according to claim 8, characterized by, The vibration measurement system further comprises an amplification unit arranged between the image acquisition unit and the measurement unit, for image amplification of the measurement unit, and the amplification multiple of the amplification unit is adjustable.

10. The vibration measurement method according to claim 9, characterized by, The step of controlling the image acquisition unit to acquire a plurality of continuous measurement images of the measurement unit further comprises: determining a resolution coefficient threshold according to the density of the line segment; selecting an amplification multiple of the amplification unit with a resolution coefficient not less than the resolution coefficient threshold.

11. A vibration measurement system, characterized by The vibration measurement system comprises an image acquisition unit, a measurement unit and a control unit, the measurement unit is fixed to a measured object, there is a preset angle between the imaging surface of the image acquisition unit and the measurement surface of the measurement unit, and the control unit is configured to execute the steps of the vibration measurement method in any one of claims 1-10.

12. The vibrational measurement system of claim 11, wherein, The vibration measurement system further comprises a focusing unit for changing the position of the image acquisition unit to adjust the distance between the image acquisition unit and the measurement unit.

13. The vibrational measurement system of claim 11, wherein, The vibration measurement system further comprises an amplification unit arranged between the image acquisition unit and the measurement unit, for image amplification of the measurement unit, and the amplification multiple of the amplification unit is adjustable.

14. The vibrational measurement system of claim 11, wherein, The vibration measurement system further comprises an angle adjustment unit for adjusting the angle between the imaging surface and the measurement surface.

15. The vibrational measurement system of claim 11, wherein, The vibration measurement system further comprises a direction adjustment unit for adjusting the shooting direction of the image acquisition unit.

16. The vibrational measurement system of claim 11, wherein, The pattern provided on the measurement surface is a periodically changing texture.

17. The vibrational measurement system of claim 16, wherein, The periodically changing texture is an equally spaced parallel line segment.

18. The vibrational measurement system of claim 11, wherein, The vibration measurement system further comprises a light supplement unit for supplementing light for the measurement unit.

19. The vibrational measurement system of claim 18, wherein, The light supplement unit comprises a fixing base and a backlight light source, the fixing base is used for detachably fixing the measuring unit on the measured object, a light transmission window is arranged on the fixing base, and the backlight light source is used for supplementing light for the measuring unit through the light transmission window.

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

21. A computer device, comprising: The storage medium stores computer readable instructions, and the computer readable instructions are executed by one or more processors to enable the one or more processors to perform the steps of the vibration measurement method according to any one of claims 1-10.

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

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