A method and system for real-time synchronous measurement of full-field three-dimensional deformation field and temperature field based on fluorescence speckle

Abstract

The present application belongs to the technical field of material deformation test, and discloses a method and system for real-time synchronous measurement of full-field three-dimensional deformation field and temperature field based on fluorescence speckle. The method comprises the following steps: S1, calibrating the curve relationship between the gray scale ratio and the temperature; S2, obtaining the matching points of each to-be-measured point in the reference image under each angle in the deformation image at all time instants, and the matching points of each point in the images of different angles at the same time instant; and S3, calculating the three-dimensional deformation field and the temperature field of the surface of the to-be-measured sample at each time instant. The present application also discloses a system for the above method. Through the present application, the synchronous three-dimensional measurement of the deformation field and the temperature field of the surface of a component is realized, the temperature measurement range is wider, the cost is lower, and the operation is simple.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field related to material deformation test, and more particularly, relates to a method and system for real-time synchronous measurement of full-field three-dimensional deformation field and temperature field based on fluorescent speckle. BACKGROUND

[0002] Variable aircraft skin skeleton, satellite antenna and other deformable components can change shape, performance and function in a predetermined manner under thermal excitation conditions, thereby meeting the application requirements of different fields. However, in the actual application process, due to the complex structure of the components themselves, and the need to withstand complex and alternating multi-field synchronous loads during service, deformation cannot successfully achieve the expected effect, which seriously restricts the safety and reliability of such components. Therefore, in order to clarify the deformation law and achieve controllable deformation, it is crucial to accurately obtain the three-dimensional measurement data of temperature-deformation field during the thermal deformation process of the component.

[0003] At present, strain measurement technology is mainly divided into contact type and non-contact type, and the latter is widely studied due to its non-contact and full-field real-time measurement characteristics. Among them, the digital image correlation method (DIC) has been rapidly developed due to its simple equipment, low environmental requirements, high precision and other characteristics. In addition, some scholars have introduced infrared temperature measurement technology based on DIC measurement to achieve synchronous measurement, but the introduction of infrared cameras has made the overall measurement accuracy of the system lower and the stability worse, and high-precision infrared cameras are expensive and have high costs; in the synchronous measurement method based on colorimetric method and DIC technology, the colorimetric method is only suitable for high-temperature environments above 1000℃, and cannot meet the needs of medium and low temperature measurement, so the application is limited; in addition, the color of the temperature indicating paint can be observed under different environments by using a color CCD camera, and the actual temperature field can be obtained by matching the calibration curve, but the overall measurement accuracy of this method is closely related to the thickness and uniformity of the temperature indicating paint coating, and the temperature measurement accuracy is low and the temperature measurement range is limited.

[0004] Therefore, there is an urgent need for a new method and new equipment that can accurately couple the three-dimensional deformation field and temperature field of deformable components, thereby providing key data support for the mechanical property evaluation and structure optimization of materials and components. SUMMARY

[0005] In view of the above defects or improvement needs of the prior art, the present application provides a method and system for real-time synchronous measurement of full-field three-dimensional deformation field and temperature field based on fluorescent speckle, which solves the problems of low measurement accuracy of deformation field and temperature field and cannot be measured synchronously.

[0006] To achieve the above object, according to one aspect of the present application, a method for real-time synchronous measurement of full-field three-dimensional deformation field and temperature field based on fluorescent speckle is provided, which comprises the following steps:

[0007] S1, collecting images of the surface of a calibration block sprayed with fluorescent speckle at different angles, calculating the gray scale ratio of each fluorescent pixel point on the surface of the calibration block in images at different angles and measuring the temperature of each fluorescent pixel point on the surface of the calibration block, so as to obtain the temperature and the gray scale ratio corresponding to each fluorescent pixel point on the surface of the calibration block, i.e. the curve relationship between the gray scale ratio and the temperature;

[0008] S2, changing the temperature of a sample to be measured sprayed with fluorescent speckle on the surface, collecting images of the surface of the sample to be measured at different angles at different time instants, taking the image collected at the initial time instant as a reference image, and performing feature matching between the images at different time instants and the reference image and between the images at different angles at the same time instant, so as to obtain the matching points of each point in the images at different angles at all time instants in the reference image and the matching points of each point in the images at different angles at the same time instant;

[0009] S3, calculating the three-dimensional coordinate change of each point in the images at different angles at any time instant relative to the matching points in the reference image, which is the three-dimensional displacement of the matching points in the reference image at any time instant, so as to obtain the three-dimensional displacement of all the matching points in all the reference images at each time instant, i.e. the three-dimensional deformation field of the surface of the sample to be measured at each time instant;

[0010] calculating the gray scale ratio of the fluorescent pixel points on the surface of the sample to be measured in the images at different angles at the same time instant, combining the curve relationship between the gray scale ratio and the temperature to obtain the temperature of each fluorescent pixel point on the surface of the sample to be measured at the same time instant, and obtaining the temperature of the non-fluorescent pixel points on the surface of the sample to be measured by interpolation, so as to obtain the temperature of all the points on the surface of the sample to be measured at each time instant, i.e. the temperature field of the surface of the sample to be measured at each time instant.

[0011] Further preferably, in step S2, the feature matching between the images at different time instants and the reference image is performed in the following manner:

[0012] extracting the feature points in the reference image and the images at different time instants, dividing the reference image into a plurality of sub-regions, and comparing each feature point in the images at different time instants with the feature points in each region in the reference image, so as to obtain the matching regions of each sub-region in the reference image in the images at different time instants and the matching points of each point in each sub-region in the matching regions.

[0013] Further preferably, for the matching region in the image at different time of each sub-region in the reference image, further optimization is performed in the following manner: the matching correlation of the sub-region and the matching region is calculated, the matching region with the maximum matching correlation is taken as the optimization target, and the position of the matching region is adjusted by using an optimization iterative algorithm to obtain the matching region with the maximum matching correlation.

[0014] Further preferably, the matching of each point in any sub-region in the reference image is further diffused and optimized in the following manner:

[0015] S21 calculates the shape function of each sub-region by using the correspondence between the sub-region and the matching region, and the shape function is taken as the shape function of the corresponding sub-region center point;

[0016] S22 transmits the shape function of the sub-region center point O in the reference image to the point Q around the center point, calculates the matching correlation of the point Q and the matching point Q' in the image at different time, and executes one of the modes of step S23 according to the size of the matching correlation until all the points in the sub-region obtain the corresponding shape function:

[0017] S23 when the matching correlation is greater than a preset maximum threshold value, the point Q and the point Q' are matched, the shape function of the point Q is the shape function of the center point O, the point Q is taken as a new center point O, and the step S22 is returned;

[0018] when the matching correlation is less than a preset minimum threshold value, the point Q and the point Q' are not matched, a new point is selected as the point Q around the center point O in the reference image, and the step S22 is returned;

[0019] when the matching correlation is between the preset maximum threshold value and the preset minimum threshold value, the shape function of the center point O is taken as the initial value of the shape function of the point Q, the maximum matching correlation between the point Q and the point Q' is taken as the optimization target, the shape function of the point Q and the position of the point Q' are iteratively optimized to obtain the optimal position of the point Q' and the optimal shape function of the point Q, the point Q is taken as a new center point O, and the step S22 is returned.

[0020] Further preferably, in step S2, the feature matching between the images at different angles at the same time is performed in the following manner:

[0021] the obtained images at multiple angles are subjected to epipolar correction so that all the image rows are aligned, and the points on all the aligned rows are matched one by one to obtain the matching points of all the points on the aligned rows;

[0022] the points are matched row by row, and thus the feature matching between the images at different angles at the same time is completed.

[0023] Further preferably, in steps S1 and S3, the gray scale ratio is the ratio of the gray scale values of a same fluorescent pixel point on the surface of the sample to be measured or the surface of the calibration block in different angle images, wherein the gray scale value of the point is obtained by dividing a region with the point as the center and calculating the gray scale values of all fluorescent pixel points in the region.

[0024] Further preferably, in step S3, the temperature of the non-fluorescent pixel point is calculated according to the following relationship:

[0025]

[0026] wherein T(a) is the temperature of the non-fluorescent pixel point a, m is the number of all calculation points in the calculation region, T(b) is the temperature of point b in the neighborhood of point a, W b is the composite weight of point b determined by distance and correlation, R b is the correlation weight value of point b, D b is the distance weight value of point b.

[0027] Further preferably, the distance weight value is calculated according to the following relationship:

[0028]

[0029] wherein D b is the distance weight value of point b, d b is the center distance value of point b, m is the number of calculation points in the calculation region, d n is the center distance value of point n in the calculation region.

[0030] Further preferably, the correlation weight value is calculated according to the following relationship:

[0031]

[0032] wherein R b is the correlation weight value of point b, C b is the cross-correlation coefficient value of point b, m is the number of calculation points in the calculation region, C n is the cross-correlation coefficient value of point n in the calculation region.

[0033] According to another aspect of the present application, a system for measuring by using the above-mentioned method for real-time synchronous measurement of full-field three-dimensional deformation field and temperature field based on fluorescent speckle is provided, which comprises an image acquisition module, a calibration module, an image matching module, a three-dimensional deformation field calculation module and a temperature field calculation module, wherein,

[0034] the image acquisition module is used for acquiring images of the surface of the sample to be measured or the calibration block at different time instants and different angles;

[0035] The calibration module is used for measuring the temperature of the calibration block surface, calculating the gray scale ratio of the corresponding points of the sample or the calibration block surface in different angle images, and constructing the curve relationship between the temperature and the gray scale ratio by using the gray scale ratio of each point of the calibration block surface obtained by the image acquisition module;

[0036] The image matching module is used for matching the points in the images at all angles at all times and the points in the reference image, and matching the points in the images at different angles at the same time;

[0037] The three-dimensional deformation field calculation module is used for calculating the three-dimensional deformation field of the sample surface at different times;

[0038] The temperature field calculation module is used for calculating the temperature field of the sample surface at different times.

[0039] Overall, compared with the prior art, the above technical scheme conceived by the present application has the following beneficial effects:

[0040] 1. The present application proposes a method for synchronously measuring three-dimensional deformation field and temperature field based on fluorescent speckle, a fluorescent material with temperature-sensitive characteristics is coated on the surface of the sample to be measured to form a fluorescent speckle, and an image containing fluorescent pixel points and non-fluorescent pixel points is obtained by photographing the surface of the sample to be measured, the method of the present application uses the fluorescent speckle excited by the ultraviolet light source as the deformation carrier, calculates the three-dimensional deformation field of all points on the surface of the sample to be measured by using the matching points obtained by image matching, and calculates the temperature field of the fluorescent pixel points and the non-fluorescent pixel points by using the gray scale information of the fluorescent pixel points at different temperatures, that is, the temperature field of all points on the surface of the sample to be measured is obtained, the coordinates of deformation and temperature are unified, and the deformation field and the temperature field data are directly and synchronously obtained, which effectively ensures the absolute synchronization of the two in time and space, realizes the synchronous three-dimensional measurement of the deformation field and the temperature field of the surface of the component, has a wider temperature measurement range, is lower in cost, and is simple to operate;

[0041] 2. The present application matches the features between the images at different times and the reference image, and between the images at different angles at the same time, can obtain the matching points of all points including the fluorescent pixel points and the non-fluorescent pixel points in the images at all angles at all times in the reference image, and the matching points of all points including the fluorescent pixel points and the non-fluorescent pixel points in each image after mutual matching between the images at different angles at the same time, and further optimizes the matching area and each matching point in each area to improve the matching accuracy;

[0042] 3. The present application obtains the temperature of non-fluorescent points by interpolation, wherein the interpolation algorithm comprehensively considers key factors such as spatial distance and correlation, and obtains the temperature value of the non-fluorescent points by assigning weights to the known point temperatures in the calculation area for weighted average, thereby ensuring the accuracy of temperature acquisition and realizing the three-dimensional reconstruction of the complete temperature field of the component surface.

[0043] 4. The present application collects three-dimensional field image cloud data of local fluorescent speckles from multiple different angles, and realizes the synchronous measurement of the complete three-dimensional deformation field and temperature field of the measured component surface by matching the local three-dimensional image point cloud fields at different angles based on point cloud data. BRIEF DESCRIPTION OF DRAWINGS

[0044] Figure 1 is the detailed flowchart of the method for real-time synchronous measurement of the complete three-dimensional deformation field and temperature field based on fluorescent speckles provided by the present application;

[0045] Figure 2 is the principle schematic diagram of the method for real-time synchronous measurement of the complete three-dimensional deformation field and temperature field based on fluorescent speckles provided by the present application;

[0046] Figure 3 is the flowchart of the matching point diffusion optimization algorithm based on optimal correlation provided by the present application;

[0047] Figure 4 is the flowchart of the multi-dimensional weighted interpolation method considering the correlation and spatial distance factors provided by the present application. DETAILED DESCRIPTION

[0048] In order to make the purpose, technical scheme and advantages of the present application clearer and more apparent, the present application will be further described in detail below in combination with the drawings and examples. It should be understood that the specific examples described herein are only used to explain the present application and do not limit the present application. In addition, the technical features involved in each embodiment of the present application described below can be combined with each other as long as they do not conflict with each other.

[0049] As Figure 1 and Figure 2 shown, a method for real-time synchronous measurement of the complete three-dimensional deformation field and temperature field based on fluorescent speckles, comprising the following steps:

[0050] S1 a fluorescent ink is prepared by mixing a fluorescent material, a colorless ink and a diluent, and is sprayed on the surface of a temperature calibration block to form a fluorescent speckle. Then the calibration block is placed on a constant temperature heating table, and a fluorescent signal of the speckle is excited by irradiating an ultraviolet light source on the calibration block. The actual temperature of the heating table is changed at regular intervals, the gray scale ratio of each fluorescent pixel point on the surface of the calibration block in the images at different angles is calculated, and the temperature of each fluorescent pixel point on the surface of the calibration block is measured to obtain the relationship between the gray scale ratio and the temperature.

[0051] The fluorescent material is a material with temperature sensitive characteristics and has the characteristics of inducing specific wavelength fluorescence under an ultraviolet light source.

[0052] Before temperature calibration, the overall measurement system needs to be calibrated to obtain the internal and external parameters of each subsystem and the overall system external parameters.

[0053] In an embodiment of the present application, the fluorescent material used is a material with temperature sensitive characteristics and has the characteristics of inducing different waveband fluorescence under an ultraviolet light source. The specific material is Sr2Si5N8:Eu powder which radiates 600-750 nm waveband fluorescence under a 365 nm excitation light source; BaMgAl 10 O 17 :Eu powder which radiates 400-500 nm waveband fluorescence under a 365 nm excitation light source. The above two materials are easily available industrial fluorescent powders, which are low in cost and excellent in fluorescent performance. The two kinds of fluorescent powders are mixed by a high-speed stirrer in a mass ratio of 1:1 to obtain the dual-phase dual-peak fluorescent material required in the present example. Other fluorescent materials with temperature sensitive characteristics can also be selected as long as they can emit specific wavelength light under specific light source excitation.

[0054] In an embodiment of the present application, before temperature calibration, the overall measurement system needs to be calibrated. The internal and external parameters of each measurement subsystem are calibrated with high precision based on Zhang Zhengyou calibration method by using a calibration board, and the external parameters of the four sets of binocular systems are calibrated by using a stereo calibration block to obtain the overall external parameters of the system for subsequent field cloud stitching.

[0055] One of the same batch of samples to be measured is taken as a calibration block for temperature calibration test, which specifically includes the following steps:

[0056] S1.1, the fluorescent material, colorless ink and diluent are mixed in a mass ratio of 5:8:2 to prepare fluorescent ink, the fluorescent material is sprayed on the surface of the temperature calibration block by a speckle spray gun or a screen printing technology to form a fluorescent speckle, and the fluorescent speckle is placed on a constant temperature heating table, and an ultraviolet light source is used as an excitation light source to excite the fluorescent speckle;

[0057] S1.2, 30-200℃ is selected as the measured interval, the temperature is heated to the predetermined temperature by the constant temperature heating table every time with an interval of 10℃, and the temperature is maintained stable for about 5 minutes after the temperature is unchanged, the images are collected by the CCD cameras of each system and the temperature is recorded;

[0058] S1.3, the temperature calibration curve can be obtained by using an exponential function to perform curve fitting on the gray scale data of the images at different temperatures and the corresponding temperatures.

[0059] S2 uses speckle spray gun or screen printing technology to process the surface of the sample to be tested, and then collects speckle images of the sample at different angles in the deformation process through four sets of binocular systems and transmits them to the computer for subsequent analysis and processing;

[0060] The speckle image collected at the initial moment is taken as a reference image, and the speckle images obtained at different moments after deformation are matched with the reference image through DIC digital image correlation, and the images at different angles at the same moment are matched through correlation.

[0061] In one embodiment, the speckle images obtained at different moments after deformation are matched with the reference image through DIC digital image correlation, and the matching is performed in the following manner:

[0062] For images collected at different moments by the same camera, the image at the initial moment is selected as a reference image, the image is divided into several large regions, and all feature points in the images at different moments are compared with the feature points in each region in the reference image one by one to obtain the matching regions of each sub-region in the reference image in the images at different moments and the matching points of each point in each sub-region in the matching regions, quickly solve the shape function parameters, and substitute them into the inverse composition Gauss Newton algorithm (IC-GN) algorithm for nonlinear iterative optimization to obtain the shape function parameters of the region center at the sub-pixel level.

[0063] The matching points are subsequently optimized, and the specific process is as shown in Figure 3 The shape function of the center point O in the reference image is transmitted to the surrounding point Q, and the shape function of the matching point Q' in the images at different moments is calculated;

[0064] When the matching correlation is greater than a preset maximum threshold, the points Q and Q' are matched, the shape function of the point Q is the shape function of the center point O, the point Q is taken as a new center point O, and the shape function transmission is continued;

[0065] When the matching correlation is less than a preset minimum threshold, the points Q and Q' are not matched, a new point is selected as the point Q around the center point O in the reference image, and the shape function transmission is continued;

[0066] When the matching correlation is between the preset maximum threshold and the preset minimum threshold, the shape function of the center point O is taken as the initial value of the shape function of the point Q, the matching correlation between the points Q and Q' is maximized as the optimization target, and the shape function of the point Q and the position of the point Q' are iteratively optimized to obtain the optimal position of the point Q' and the optimal shape function of the point Q. The point Q is taken as a new center point O, and the shape function transmission is continued until the matching in the time domain of all sub-regions in the image is completed.

[0067] In one embodiment of the present application, the matching degree between points is calculated by using a zero-mean normalized cross-correlation coefficient.

[0068] In one embodiment of the present application, the feature matching is performed between images of different angles at the same time, in the following way:

[0069] For images of multiple angles acquired at the same time, after polar correction, the sub-regions are also used as units, and the piecewise search is used in the disparity search range on the polar line, and the integral graph is used to accelerate the calculation process of the correlation coefficient, so as to obtain the optimal matching point of the integer pixel.

[0070] The IC-GN-based iterative optimization is performed on the integer-pixel matching point pair, so as to obtain the high-precision sub-pixel optimal matching point, and all the matching points are traversed until the calculation of all the matching points between the speckle images is completed.

[0071] S3 calculates the three-dimensional coordinate change of the point in each angle image relative to the matching point in the reference image at the same time, and the coordinate change is the three-dimensional displacement of the point in the reference image at the current time, so as to obtain the three-dimensional displacement of all the points in the reference image at each time, and the three-dimensional displacement of all the points in the reference image of all the angles is the three-dimensional deformation field of the surface of the sample at each time.

[0072] The position and shape change of the speckle pattern is used to calculate the full-field three-dimensional deformation field of the speckle sample at different times, and the gray value change of the pixel point containing the fluorescent speckle in the speckle image is used to combine the temperature calibration curve to realize the real-time measurement of the full-field three-dimensional temperature field.

[0073] In one embodiment of the present application, the gray value is obtained by dividing a region with the point as the center and using the gray values of all the fluorescent pixel points in the region for weighted calculation, and the weight is the distance weight. According to the matching results of the left and right cameras obtained during the deformation calculation, the gray ratio of the gray values of the corresponding matching points of the multiple angle images is calculated, and the temperature of the fluorescent pixel point is solved by substituting the intensity ratio and the temperature curve, and all the sub-regions are traversed to solve the temperature of all the fluorescent pixel points in the image.

[0074] For the non-fluorescent pixel points, the multi-dimensional weight interpolation algorithm based on the correlation and the distance is used to interpolate and reconstruct the temperature information of the background region, so as to restore the complete temperature field of the sample surface.

[0075] In one embodiment of the present application, as shown in Figure 4 The multi-dimensional weight interpolation algorithm mainly searches the temperature known points in the neighborhood range of the point to be calculated, and assigns the interpolation weight based on the distance between the points and the correlation coefficient of the speckle matching, and the formula is expressed as:

[0076]

[0077] wherein T(a) is the temperature of the non-fluorescent pixel point a, m is the total number of points to be calculated in the calculation region, T(b) is the temperature of point b in the neighborhood of point a, W b is the composite weight determined according to the distance and the correlation; R b , R n is the weight assigned to point b and point n according to the correlation coefficient in the time domain matching process, and the greater the correlation, the higher the weight assigned. b , D n is the weight assigned to point b and point n according to the distance between the current point and the points in the neighborhood, and the closer the distance, the higher the weight assigned.

[0078] Those skilled in the art will easily understand that the above description is only the preferred embodiment of the present application, and is not intended to limit the present application, and any modification, equivalent replacement and improvement made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A method for real-time synchronous measurement of full-field three-dimensional deformation field and temperature field based on fluorescence speckle, characterized in that, The method comprises the following steps: S1, collecting images of the surface of the calibration block sprayed with fluorescent speckles at different angles, calculating the gray scale ratio of each fluorescent pixel point on the surface of the calibration block in images at different angles, and measuring the temperature of each fluorescent pixel point on the surface of the calibration block, so as to obtain the temperature and the gray scale ratio corresponding to each fluorescent pixel point on the surface of the calibration block, that is, the curve relationship between the gray scale ratio and the temperature; S2, changing the temperature of the sample to be measured whose surface is sprayed with fluorescent speckles, collecting images of the surface of the sample to be measured at different angles at different time instants, taking the image collected at the initial time instant as a reference image, and performing feature matching between the images at different time instants and the reference image and between the images at different angles at the same time instant, so as to obtain the matching points of each point in the images at different angles at all time instants in the reference image and the matching points of each point in the images at different angles at the same time instant in each other image; S3, calculating the three-dimensional coordinate change of each point in the images at different angles at any time instant relative to the matching point in the reference image, which is the three-dimensional displacement of the matching point in the reference image at any time instant, so as to obtain the three-dimensional displacement of all the matching points in all the reference images at each time instant, that is, the three-dimensional deformation field of the surface of the sample to be measured at each time instant; calculating the gray scale ratio of the matching points of the fluorescent pixel points on the surface of the sample to be measured in the images at different angles at the same time instant, combining the curve relationship between the gray scale ratio and the temperature to obtain the temperature of each fluorescent pixel point on the surface of the sample to be measured at the same time instant, and obtaining the temperature of the non-fluorescent pixel points on the surface of the sample to be measured by an interpolation method, so as to obtain the temperature of all the points on the surface of the sample to be measured at each time instant, that is, the temperature field of the surface of the sample to be measured at each time instant.

2. The method for real-time synchronization measurement of full-field three-dimensional deformation field and temperature field based on fluorescent speckle according to claim 1, characterized in that, In step S2, the feature matching between the images at different time instants and the reference image is performed in the following manner: extracting feature points in the reference image and the images at different time instants, dividing the reference image into a plurality of sub-regions, and comparing each feature point in the images at different time instants with the feature points in each region in the reference image one by one to obtain the matching regions of each sub-region in the reference image in the images at different time instants and the matching points of each point in each sub-region in the matching regions.

3. The method for real-time synchronization measurement of full-field three-dimensional deformation field and temperature field based on fluorescent speckle according to claim 2, characterized in that, For the matching regions of each sub-region in the reference image in the images at different time instants, further optimization is performed in the following manner: calculating the matching correlation degree of the sub-region and the matching region, taking the maximum matching correlation degree as the optimization target, and adjusting the position of the matching region by using an optimization iterative algorithm to obtain the matching region with the maximum matching correlation degree.

4. The method for real-time synchronization measurement of full-field three-dimensional deformation field and temperature field based on fluorescent speckle according to claim 2 or 3, characterized in that, The matching points of each point in each sub-region in the reference image in the matching regions are further diffused and optimized in the following manner: S21, calculating the shape function of each sub-region by using the corresponding relationship between the sub-region and the matching region, which is the shape function of the center point of the corresponding sub-region; S22, transferring the shape function of the center point O of the sub-region in the reference image to the surrounding point Q, calculating the matching correlation degree of the point Q and the matching point Q' in the images at different time instants, and selecting one of the ways in step S23 for execution according to the size of the matching correlation degree until each point in the sub-region obtains the corresponding shape function: S23 when the matching correlation is greater than the preset maximum threshold, the point Q and Q' match, the shape function of the point Q is the shape function of the center point O, taking the point Q as a new center point O, returning to step S22; when the matching correlation is less than the preset minimum threshold, the point Q and Q' do not match, selecting a new point as the point Q around the center point O of the reference image, returning to step S22; when the matching correlation is between the preset maximum threshold and the preset minimum threshold, taking the shape function of the center point O as the initial value of the shape function of the point Q, the maximum matching correlation between the point Q and Q' is the optimization target, iteratively optimizing the shape function of the point Q and the position of the point Q', obtaining the optimal position of the point Q' and the optimal shape function of the point Q, taking the point Q as a new center point O, returning to step S22.

5. The method for real-time synchronization measurement of full-field three-dimensional deformation field and temperature field based on fluorescent speckle according to claim 1 or 2, characterized in that, In step S2, the feature matching between the images of different angles at the same time is performed in the following manner: performing polar correction on the obtained images of multiple angles so that all the image rows are aligned; matching the points on all the aligned rows one by one to obtain the matching points of all the points on the aligned rows; matching row by row to complete the feature matching of all the points between the images of different angles at the same time.

6. The method for real-time synchronization measurement of full-field three-dimensional deformation field and temperature field based on fluorescent speckle according to claim 1 or 2, characterized in that, In steps S1 and S3, the gray ratio is the ratio of the gray values of the same fluorescent pixel point on the surface of the sample to be measured or the surface of the calibration block in the images of different angles, wherein the gray value of the point is obtained by weighting the gray values of all the fluorescent pixel points in a region centered on the point.

7. The method for real-time synchronization measurement of full-field three-dimensional deformation field and temperature field based on fluorescent speckle according to claim 1 or 2, characterized in that, In step S3, the temperature of the non-fluorescent pixel point is calculated according to the following relationship: wherein T(a) is the temperature of the non-fluorescent pixel point a, m is the number of all points to be calculated in the calculation region, T(b) is the temperature of point b in the neighborhood of point a, W b is the composite weight of point b determined by distance and correlation, R b is the correlation weight value of point b, D b is the distance weight value of point b.

8. The method for real-time synchronization measurement of full-field three-dimensional deformation field and temperature field based on fluorescent speckle according to claim 7, characterized in that, the distance weight value is calculated according to the following relationship: wherein D b is the distance weight value of the point b, d b is the center distance value of the point b, m is the number of calculation points in the calculation area, d n is the center point distance value of the point n in the calculation area.

9. The method for real-time synchronization measurement of full-field three-dimensional deformation field and temperature field based on fluorescent speckle according to claim 7, characterized in that, the correlation weight value is calculated according to the following relationship: wherein R b is the correlation weight value of the point b, C b is the cross-correlation coefficient value of the point b, m is the number of calculation points in the calculation region, and C n is the cross-correlation coefficient value of the point n in the calculation region.

10. A system for measuring by the method of any one of claims 1-9, characterized in that, The system comprises an image acquisition module, a calibration module, an image matching module, a three-dimensional deformation field calculation module and a temperature field calculation module, wherein, the image acquisition module is used to acquire images of the surface of the sample to be measured or the surface of the calibration block at different times and different angles; the calibration module is used to measure the temperature of the surface of the calibration block, calculate the gray ratio of the same point on the surface of the sample to be measured or the calibration block in different angle images, and construct the curve relationship between the temperature and the gray ratio by using the gray ratio of each point on the surface of the calibration block obtained by the image acquisition module; the image matching module is used to perform feature matching to obtain the matching relationship between each point in the images at all times and all angles and each point in the reference image, and the matching relationship between each point in the images of different angles at the same time; the three-dimensional deformation field calculation module is used to calculate the three-dimensional deformation field of the surface of the sample to be measured at different times; the temperature field calculation module is used to calculate the temperature field of the surface of the sample to be measured at different times.

Images