Multi-light-spot anti-interference deformation measuring device and method based on stroboscopic energy spectrum

Abstract

The invention discloses a multi-light-spot anti-interference deformation measuring device and method based on stroboscopic energy spectrum.The multi-light-spot anti-interference deformation measuring device comprises a point light source, a first cylindrical mirror is arranged below the point light source, a first linear array sensor is arranged below the first cylindrical mirror, and the first linear array sensor is electrically connected with a data acquisition device; light emitted by the point light source passes through the first cylindrical mirror and then is focused into a line segment to be imaged on the first linear array sensor, and the first linear array sensor converts optical signals of the focused line segment into digital signals and outputs the digital signals to the data acquisition device. According to the multi-light-spot anti-interference deformation measuring device, a multi-dimensional displacement sensor measuring system is established by applying the cylindrical mirror, the linear array sensor and the point light source, a displacement measuring system with high precision, high resolution and high sampling rate can be realized, and the multi-light-spot anti-interference deformation measuring device is few in related components, small in size, simple to maintain, low in cost, high in system stability and easy to popularize. The method is more suitable for outdoor multi-point monitoring of engineering structures.

Description

Technical Field

[0001] The present invention relates to the field of precision measurement technology, and in particular to a multi-light-spot anti-torsion deformation measurement device and method based on stroboscopic energy spectrum. Background Art

[0002] Deformation measurement devices, also known as displacement sensors, are key measurement tools widely used to detect the position, displacement, and motion of objects. They play an indispensable role in modern industry, scientific research, and everyday life. Their widespread use stems from the strong demand for position and displacement information, which is of great value in fields such as industrial automation, precision manufacturing, and structural health monitoring. As requirements for measurement accuracy, response speed, reliability, and environmental adaptability continue to increase across various industries, displacement sensor technology has rapidly developed and has assumed a pivotal position in modern science and industry.

[0003] Currently, there are many types of displacement sensors, and common types include strain gauge, inductive, differential transformer, grating, capacitance grating, laser, and fiber optic sensors. These sensors are usually based on direct contact with the surface of the object and achieve measurement by recording the displacement difference between the starting position and the final position. However, this type of displacement sensor still has significant defects in practical applications: 1. Single measurement direction; 2. Limited environmental adaptability; 3. Insufficient dynamic response capability; 4. Installation and use restrictions. At the same time, when the lighting is complex or the environment changes frequently, the detection of the cursor point becomes difficult in the existing technology, resulting in a decrease in measurement accuracy. These defects limit the application effect of displacement sensors in complex, multi-dimensional displacement measurements, and also put forward higher requirements for the accuracy, reliability, and environmental adaptability of the sensors. Summary of the Invention

[0004] The purpose of the present invention is to solve the shortcomings of the prior art and to propose a multi-light-spot anti-torsion deformation measurement device and method based on stroboscopic energy spectrum.

[0005] In order to achieve the above object, the present invention adopts the following technical solutions:

[0006] A multi-light-spot anti-interference deformation measurement device based on stroboscope energy spectrum includes a point light source, a cylindrical mirror 1 is arranged below the point light source, a linear array sensor 1 is arranged below the cylindrical mirror 1, and the linear array sensor 1 is electrically connected to a data acquisition device. Light emitted by the point light source passes through the cylindrical mirror 1 and is focused into a line segment, which is imaged on the linear array sensor 1. The linear array sensor 1 converts the light signal of the focused line segment into a digital signal and outputs it to the data acquisition device. The data acquisition device determines the position of the focused line segment on the linear array sensor 1 based on the digital signal of the focused line segment on the linear array sensor 1, and calculates the position change of the focused line segment at different times. The position change corresponds one-to-one with the displacement of the point light source in the direction of the linear array sensor 1. The displacement of the point light source in the direction of the linear array sensor 1 is further calculated based on the imaging relationship.

[0007] Preferably, it further includes a beam splitter prism 1, which is located between the point light source and the cylindrical mirror 1. A cylindrical mirror 2 is provided on one side of the beam splitter prism 1, and a linear array sensor 2 is provided on the other side of the cylindrical mirror 2. The linear array sensor 2 is electrically connected to the data acquisition device. The cylindrical mirror 1, the linear array sensor 1, the beam splitter prism 1, the cylindrical mirror 2, and the linear array sensor 2 constitute a two-dimensional displacement sensor.

[0008] Preferably, the cylindrical mirror 1 is a cylindrical mirror placed horizontally perpendicular to the direction of light irradiation, and the cylindrical mirror 1 has curvature in the vertical direction and no curvature in the horizontal direction;

[0009] The cylindrical mirror 2 is a cylindrical mirror placed vertically in the direction of vertical light irradiation. The cylindrical mirror 2 has no curvature in the vertical direction but has curvature in the horizontal direction.

[0010] Preferably, the first linear array sensor is a linear array CCD or a linear array CMOS or a linear array photon counting sensor, and the second linear array sensor is a linear array CCD or a linear array CMOS or a linear array photon counting sensor.

[0011] Preferably, the device further comprises a second beam splitter prism, a third cylindrical mirror is provided below the second beam splitter prism, a third linear array sensor is provided below the third cylindrical mirror, the third linear array sensor is electrically connected to a data acquisition device, the second beam splitter prism is located between the point light source and the third cylindrical mirror, a fourth cylindrical mirror is provided on one side of the second beam splitter prism, a fourth linear array sensor is provided on the other side of the fourth cylindrical mirror, and the fourth linear array sensor is electrically connected to the data acquisition device;

[0012] The cylindrical mirror 1, linear array sensor 1, beam splitter prism 1, cylindrical mirror 2, linear array sensor 2 and the cylindrical mirror 3, linear array sensor 3, beam splitter prism 2, cylindrical mirror 4, linear array sensor 4 respectively constitute two two-dimensional displacement sensors, and the two two-dimensional displacement sensors jointly image the point light source, and the two two-dimensional displacement sensors constitute a three-dimensional displacement sensor.

[0013] A multi-light-point anti-interference deformation measurement method based on stroboscopic energy spectrum includes the following steps:

[0014] S1. Fix F point light sources with different stroboscopic frequencies f(i) at the deformation points of interest of the target to be measured. If the target to be measured has multiple target planes, ensure that there are at least two point light sources in each target plane. The point light sources are active cursors.

[0015] S2. Select two characteristic active cursors, which are located in the same target plane and at a certain distance from each other in the direction of deformation to be measured, and measure the distance d1 between the two active cursors in the target plane and in the direction of deformation to be measured using a standard measuring tool;

[0016] S3. If the target to be measured has W different target planes, repeat S2 to measure the distance dw between the two active cursors in the direction of deformation to be measured in the wth different target plane to be measured;

[0017] S4. The measuring device is aligned with the target to be measured, the linear array sensor 1 is parallel to the deformation direction to be measured, and F active cursors are simultaneously focused on the linear array sensor 1 through the cylindrical mirror 1;

[0018] S5, collecting pixel values ​​corresponding to P pixels in a row of the linear array sensor;

[0019] S6, repeat S5, collecting N×P pixel values ​​corresponding to N rows of P pixels of the linear array sensor;

[0020] S7. Collect the P-th pixel into N×P pixel values ​​and perform frequency domain analysis based on short-time Fourier transform to obtain the energy spectrum of each pixel.

[0021] S8. Searching for the energy value corresponding to the stroboscopic frequency f(i) of the i-th active cursor on each pixel energy spectrum signal;

[0022] S9, calculating the displacement value corresponding to the i-th active cursor strobe frequency f(i) according to the energy spectrum signal of each pixel;

[0023] S10, repeating steps S5 to S9 to obtain F time-frequency displacement sequences D(i, t) of active cursors with different strobe frequencies f(i);

[0024] Preferably, in step S4, the linear array sensor 1 is focused, and the busbar of the cylindrical mirror 1 is perpendicular to the pixel arrangement direction of the linear array sensor 1.

[0025] Preferably, the step S7 specifically includes the following steps:

[0026] S71, read in N pixel values ​​corresponding to the p-th pixel;

[0027] S72, using windowing to collect the signal X(p,n) from each pixel point, to obtain the mth windowed signal X m (p, n);

[0028] S73, the pixel signal X after windowing m (p, n) performs short-time Fourier transform to obtain the corresponding signal spectrum FT m (p, k);

[0029] S74, transform the signal spectrum FT m (p, k) takes the absolute value to get the linear spectrum S m (p, k);

[0030] S75, the linear spectrum S m The square of the modulus of (p, k) gives the energy E m (p, k);

[0031] Preferably, in step S8, the energy spectrum E of each pixel is m (p, k), search along the frequency axis for the maximum energy value e corresponding to F strobe frequencies f(i) m (p, i).

[0032] Preferably, the step S9 specifically includes the following steps:

[0033] S91, for F different stroboscopic frequencies f(i), the energy value e of each pixel corresponding to the stroboscopic frequency f(i) is m (i) Synthesize F sequences Y according to the original pixel order of the image sensor m (p, i);

[0034] S92, adaptive estimation sequence Y m Energy threshold T(i) of (p, i);

[0035] S93, sequence Y m The grayscale values ​​of pixels in (p, i) that are less than the energy threshold T(i) are set to 0, and the grayscale values ​​of pixels that are greater than the energy threshold are retained as the original values, and the sequence Y is regenerated. m '(p, i);

[0036] S94, using the grayscale centroid method, calculate the corresponding sequence Y of all stroboscopic frequencies f(i) m '(p, i)'s center of gravity position sub-pixel value C(i);

[0037] S95, searching for the distance dw between two characteristic cursors in the deformation direction to be measured in the w-th target plane and their corresponding sub-pixel values ​​of the center of gravity Cw(j) and Cw(k) in all W target planes to be measured;

[0038] The distance Lw from the linear array sensor 1 to the w-th target plane is calculated based on the focal length of the cylindrical mirror 1, the distance dw between the two characteristic cursors in the target plane, and the corresponding sub-pixel values ​​Cw(j) and Cw(k) of the center of gravity.

[0039] S96. The corresponding sequence Y of all stroboscopic frequencies f(i) can be obtained by calculating the focal length of the cylindrical mirror and the distance Lw from the linear array sensor to the target plane. m '(p, i) The sub-pixel value C(i) of the center of gravity corresponds to the displacement value D(i).

[0040] The beneficial effects of the present invention are:

[0041] 1. In the present invention, the multi-light-point anti-interference deformation measurement device establishes a multi-dimensional displacement sensor measurement system by applying a cylindrical mirror, a linear array sensor and a point light source, which can achieve a high-precision, high-resolution and high-sampling-rate displacement measurement system. It involves few components, has a compact shape, is easy to maintain, has low cost and high system stability, and is more suitable for outdoor multi-point monitoring of engineering structures.

[0042] 2. In the present invention, the multi-cursor deformation measurement method collects stroboscopic mark images obtained by cylindrical mirrors on multiple linear array sensors, performs Fourier transform on the grayscale values ​​of the multiple images at each pixel coordinate on the image along the time direction, and records the energy spectrum value corresponding to the cursor frequency on the spectrum graph at the pixel. After the energy spectrum value of the cursor is recorded at each pixel on the image, the pixel position with the largest energy spectrum value is the cursor position. Since the sampling frequency of the linear array sensor is much higher than the stroboscopic frequency of the cursor, there is sufficient bandwidth for multi-cursor measurement. At the same time, since each cursor has its own unique frequency, it is easy to distinguish between two cursors even if they overlap at the same position. This also makes the cursor recognition highly resistant to ambient light interference. BRIEF DESCRIPTION OF THE DRAWINGS

[0043] Figure 1 Schematic diagram of the structure of embodiment 1 of a multi-light-spot anti-torsion deformation measurement device based on stroboscopic energy spectrum of the present invention.

[0044] Figure 2 Schematic diagram of the structure of embodiment 2 of a multi-light-spot anti-torsion deformation measurement device based on stroboscopic energy spectrum of the present invention.

[0045] Figure 3 Schematic diagram of the structure of embodiment 3 of a multi-light-spot anti-torsion deformation measurement device based on stroboscopic energy spectrum of the present invention.

[0046] Figure 4 The present invention is a measurement flow chart of a multi-light-spot anti-torsion deformation measurement method based on stroboscopic energy spectrum.

[0047] Figure 5 The figure is a frequency domain calculation flow chart of a multi-light-spot anti-torsion deformation measurement method based on stroboscopic energy spectrum of the present invention.

[0048] Figure 6 The present invention is a flow chart of displacement calculation of a multi-light-spot anti-torsion deformation measurement method based on stroboscopic energy spectrum.

[0049] Numbers in the figure: 1, point light source; 2, cylindrical mirror 1; 3, linear array sensor 1; 4, data acquisition device; 5, beam splitter prism 1; 6, cylindrical mirror 2; 7, linear array sensor 2; 8, cylindrical mirror 3; 9, linear array sensor 3; 10, beam splitter prism 2; 11, cylindrical mirror 4; 12, linear array sensor 4. DETAILED DESCRIPTION

[0050] The technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments.

[0051] Example 1, as shown in the attached Figure 1 As shown:

[0052] A multi-light-point anti-interference deformation measurement device based on stroboscopic energy spectrum includes a point light source 1, a cylindrical mirror 2 is arranged below the point light source 1, a linear array sensor 3 is arranged below the cylindrical mirror 2, and the linear array sensor 3 is electrically connected to a data acquisition device 4. The light emitted by the point light source 1 is focused into a line segment after passing through the cylindrical mirror 2 and is imaged on the linear array sensor 3. Figure 1 As shown, the linear array sensor 3 converts the optical signal of the focused line segment into a digital signal and outputs it to the data acquisition device 4. The data acquisition device 4 is a computer. The data acquisition device 4 determines the position of the focused line segment on the linear array sensor 3 based on the digital signal of the focused line segment on the linear array sensor 3, and calculates the position change of the focused line segment at different times. The position change corresponds one-to-one with the displacement of the point light source 1 in the direction of the linear array sensor 3. The displacement of the point light source 1 in the direction of the linear array sensor 3 is further calculated based on the imaging relationship. By fixing the point light source 1 on a structure, it can be used for dynamic and static displacement measurement and monitoring in various engineering occasions such as ground subsidence, bridge deformation, and large equipment.

[0053] It is worth mentioning that the size and brightness of the point light source 1 are determined by the measurement distance, and its size can range from tens of microns to hundreds of millimeters. It is focused into a focal line by the cylindrical mirror 2. The line array sensor 3 is composed of a single row or several rows of photosensitive elements (pixels), arranged in a straight line, usually containing thousands to tens of thousands of pixels, each pixel independently sensitive to light.

[0054] Embodiment 2 is the second embodiment of the present invention, which is based on the first embodiment:

[0055] As attached Figure 2 As shown, a multi-light point anti-interference deformation measurement device based on stroboscopic energy spectrum also includes a beam splitter prism 5, which is located between the point light source 1 and the cylindrical mirror 2. A cylindrical mirror 6 is provided on one side of the beam splitter prism 5, and a linear array sensor 7 is provided on the other side of the cylindrical mirror 6. The linear array sensor 7 is electrically connected to the data acquisition device 4.

[0056] Cylindrical mirror 2 is a cylindrical mirror placed horizontally perpendicular to the direction of light irradiation. Cylindrical mirror 2 has curvature in the vertical direction but no curvature in the horizontal direction. Cylindrical mirror 2 does not change the propagation path of light in the horizontal direction, that is, the light propagates in the original direction and has no focusing effect. Therefore, the image does not form a point, but can form a horizontal focal line.

[0057] The cylindrical mirror 2 6 is a cylindrical mirror placed vertically in the direction of vertical light irradiation. The cylindrical mirror 2 6 has no curvature in the vertical direction but has curvature in the horizontal direction. The cylindrical mirror 2 6 does not change the propagation path of the light in the vertical direction, that is, the light propagates in the original direction and has no focusing effect. Therefore, the image does not form a point, but can form a vertical focal line.

[0058] In the above technical solution, the design of cylindrical mirror 2 6 and linear array sensor 2 7 realizes two-dimensional spatial displacement measurement. Cylindrical mirror 1 2, linear array sensor 1 3, beam splitter prism 1 5, cylindrical mirror 2 6, and linear array sensor 2 7 constitute a two-dimensional displacement sensor.

[0059] The first linear array sensor 3 is a linear array CCD or a linear array CMOS or a linear array photon counting sensor, and the second linear array sensor 7 is a linear array CCD or a linear array CMOS or a linear array photon counting sensor.

[0060] Embodiment 3 is the third embodiment of the present invention, which is based on the second embodiment:

[0061] As attached Figure 3 As shown, a multi-light point anti-interference deformation measurement device based on stroboscopic energy spectrum also includes a second beam splitter prism 10, a cylindrical mirror 3 8 is provided below the second beam splitter prism 10, a linear array sensor 3 9 is provided below the cylindrical mirror 3 8, and the linear array sensor 3 9 is electrically connected to the data acquisition device 4. The second beam splitter prism 10 is located between the point light source 1 and the cylindrical mirror 3 8. A cylindrical mirror 4 11 is provided on one side of the second beam splitter prism 10, and a linear array sensor 4 12 is provided on the other side of the cylindrical mirror 4 11. The linear array sensor 4 12 is electrically connected to the data acquisition device;

[0062] In the above technical solution, cylindrical mirror 1 2, linear array sensor 1 3, dichroic prism 1 5, cylindrical mirror 2 6, linear array sensor 2 7 and cylindrical mirror 3 8, linear array sensor 3 9, dichroic prism 2 10, cylindrical mirror 4 11, linear array sensor 4 12 respectively constitute two two-dimensional displacement sensors, and the two two-dimensional displacement sensors jointly image the point light source. The two two-dimensional displacement sensors constitute a three-dimensional displacement sensor to realize three-dimensional spatial displacement measurement.

[0063] Specifically, as attached Figure 3 As shown, two two-dimensional displacement sensors are used to image point P. The coordinates x1 and x2 of this point are obtained by cylindrical mirror 2 6, cylindrical mirror 4 11, and linear array sensor 2 7 and linear array sensor 4 12. The coordinates y1 and y2 are obtained by cylindrical mirror 1 2, cylindrical mirror 3 8, and linear array sensor 1 3 and linear array sensor 3 9. According to the perspective transformation model of stereo vision:

[0064]

[0065] Among them, s1 and s2 are scaling factors, f 1x 、f 2x 、f 1y 、f 2y are the focal lengths of cylindrical mirror 1 2, cylindrical mirror 2 6, cylindrical mirror 3 8, and cylindrical mirror 4 11, respectively; (X1, Y1, Z1) and (X2, Y2, Z2) are the spatial coordinate systems of two two-dimensional displacement sensors, respectively.

[0066] The coordinate systems of the two 2D displacement sensors can be transformed into rigid bodies using the rotation matrix R and the translation matrix T:

[0067]

[0068] When the coordinates of the spatial point in the two two-dimensional displacement sensors are P1(x1, y1), P2(x2, y2) and the focal length of the camera is f 1x 、f 2x 、f 1y 、f 2y When the external parameters R and T matrices of the two 2D sensors are known, the world coordinates are built on the 2D sensor (X1, Y1, Z1) coordinate system to solve the 3D coordinates of the spatial point P:

[0069]

[0070] Embodiment 4 is the fourth embodiment of the present invention, which is based on the first embodiment:

[0071] As attached Figure 1 and attached Figure 4 To the attached Figure 6As shown, a multi-light point anti-interference deformation measurement method based on stroboscope energy spectrum is implemented based on a multi-light point anti-interference deformation measurement device based on stroboscope energy spectrum, including the following steps:

[0072] S1. Fix F point light sources with different stroboscopic frequencies f(i) at the deformation points of interest of the target to be measured. If the target to be measured has multiple target planes, ensure that there are at least two point light sources in each target plane. The point light sources are active cursors.

[0073] S2. Select two characteristic active cursors, which are located in the same target plane and at a certain distance from each other in the direction of deformation to be measured, and measure the distance d1 between the two active cursors in the target plane and in the direction of deformation to be measured using a standard measuring tool;

[0074] S3. If the target to be measured has W different target planes, repeat S2 to measure the distance dw between the two active cursors in the direction of deformation to be measured in the wth different target plane to be measured;

[0075] S4. The measuring device is aligned with the target to be measured, the linear array sensor 1 is parallel to the deformation direction to be measured, and F active cursors are simultaneously focused on the linear array sensor 1 through the cylindrical mirror 1;

[0076] In step S4, focusing is performed on the linear array sensor 1, and the busbar of the cylindrical mirror 1 is perpendicular to the pixel arrangement direction of the linear array sensor 1;

[0077] S5, collecting pixel values ​​corresponding to P pixels in a row of the linear array sensor;

[0078] S6, repeat S5, collecting N×P pixel values ​​corresponding to N rows of P pixels of the linear array sensor;

[0079] S7. Collect the P-th pixel into N×P pixel values ​​and perform frequency domain analysis based on short-time Fourier transform to obtain the energy spectrum of each pixel.

[0080] Step S7 specifically includes the following steps:

[0081] S71, read in N pixel values ​​corresponding to the p-th pixel;

[0082] S72, using windowing to collect the signal X(p,n) from each pixel point, to obtain the mth windowed signal X m (p, n);

[0083] S73, the pixel signal X after windowing m (p, n) performs short-time Fourier transform to obtain the corresponding signal spectrum FT m (p, k);

[0084] S74, transform the signal spectrum FTm (p, k) takes the absolute value to get the linear spectrum S m (p, k);

[0085] S75, the linear spectrum S m The square of the modulus of (p, k) gives the energy E m (p, k);

[0086] S8. Searching for the energy value corresponding to the stroboscopic frequency f(i) of the i-th active cursor on each pixel energy spectrum signal;

[0087] In step S8, the energy spectrum E of each pixel is m (p, k), search along the frequency axis for the maximum energy value e corresponding to F strobe frequencies f(i) m (p, i);

[0088] S9, calculating the displacement value corresponding to the i-th active cursor strobe frequency f(i) according to the energy spectrum signal of each pixel;

[0089] Step S9 specifically includes the following steps:

[0090] S91, for F different stroboscopic frequencies f(i), the energy value e of each pixel corresponding to the stroboscopic frequency f(i) is m (i) Synthesize F sequences Y according to the original pixel order of the image sensor m (p, i);

[0091] S92, adaptive estimation sequence Y m Energy threshold T(i) of (p, i);

[0092] S93, sequence Y m The grayscale values ​​of pixels in (p, i) that are less than the energy threshold T(i) are set to 0, and the grayscale values ​​of pixels that are greater than the energy threshold are retained as the original values, and the sequence Y is regenerated. m '(p, i);

[0093] S94, using the grayscale centroid method, calculate the corresponding sequence Y of all stroboscopic frequencies f(i) m '(p, i)'s center of gravity position sub-pixel value C(i);

[0094] S95, searching for the distance dw between two characteristic cursors in the deformation direction to be measured in the w-th target plane and their corresponding sub-pixel values ​​of the center of gravity Cw(j) and Cw(k) in all W target planes to be measured;

[0095] The distance Lw from the linear array sensor 1 to the w-th target plane is calculated based on the focal length of the cylindrical mirror 1, the distance dw between the two characteristic cursors in the target plane, and the corresponding sub-pixel values ​​Cw(j) and Cw(k) of the center of gravity.

[0096] S96. The corresponding sequence Y of all stroboscopic frequencies f(i) can be obtained by calculating the focal length of the cylindrical mirror and the distance Lw from the linear array sensor to the target plane. m '(p, i) The sub-pixel value C(i) of the center of gravity corresponds to the displacement value D(i);

[0097] S10. Repeat steps S5 to S9 to obtain F time-frequency displacement sequences D(i, t) of active cursors with different strobe frequencies f(i).

[0098] The above description is only a preferred specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any technician familiar with the technical field, within the technical scope disclosed by the present invention, who makes equivalent replacements or changes based on the technical solution and inventive concept of the present invention, should be covered by the scope of protection of the present invention.

Claims

1. A multi-light point anti-interference deformation measurement device based on stroboscopic energy spectrum, including a point light source, characterized in that: A cylindrical mirror 1 is provided below the point light source, and a linear array sensor 1 is provided below the cylindrical mirror 1. The linear array sensor 1 is electrically connected to a data acquisition device. The light emitted by the point light source is focused into a line segment after passing through the cylindrical mirror 1, and an image is formed on the linear array sensor 1. The linear array sensor 1 converts the light signal of the focused line segment into a digital signal and outputs it to the data acquisition device. The data acquisition device determines the position of the focused line segment on the linear array sensor 1 based on the digital signal of the focused line segment on the linear array sensor 1, and calculates the position change of the focused line segment at different times. The position change corresponds one-to-one to the displacement of the point light source in the direction of the linear array sensor 1, and further calculates the displacement of the point light source in the direction of the linear array sensor 1 based on the imaging relationship.

2. The multi-light-spot anti-torsion deformation measuring device based on stroboscopic energy spectrum according to claim 1 is characterized in that: It also includes a first beam splitter prism, which is located between a point light source and a first cylindrical mirror. A second cylindrical mirror is provided on one side of the first beam splitter prism, and a second linear array sensor is provided on the other side of the second cylindrical mirror. The second linear array sensor is electrically connected to a data acquisition device. The first cylindrical mirror, the first linear array sensor, the first beam splitter prism, the second cylindrical mirror, and the second linear array sensor constitute a two-dimensional displacement sensor.

3. The multi-light-spot anti-torsion deformation measuring device based on stroboscopic energy spectrum according to claim 2 is characterized in that: The cylindrical mirror 1 is a cylindrical mirror placed horizontally in the direction perpendicular to the light irradiation direction, and the cylindrical mirror 1 has curvature in the vertical direction and no curvature in the horizontal direction; The cylindrical mirror 2 is a cylindrical mirror placed vertically in the direction of vertical light irradiation. The cylindrical mirror 2 has no curvature in the vertical direction but has curvature in the horizontal direction.

4. The multi-light-spot anti-torsion deformation measuring device based on stroboscopic energy spectrum according to claim 3 is characterized in that: The first linear array sensor is a linear array CCD or a linear array CMOS or a linear array photon counting sensor, and the second linear array sensor is a linear array CCD or a linear array CMOS or a linear array photon counting sensor.

5. The multi-light-spot anti-torsion deformation measuring device based on stroboscopic energy spectrum according to claim 4 is characterized in that: The device further comprises a second beam splitter prism, a third cylindrical mirror is provided below the second beam splitter prism, a third linear array sensor is provided below the third cylindrical mirror, the third linear array sensor is electrically connected to a data acquisition device, the second beam splitter prism is located between the point light source and the third cylindrical mirror, a fourth cylindrical mirror is provided on one side of the second beam splitter prism, a fourth linear array sensor is provided on the other side of the fourth cylindrical mirror, and the fourth linear array sensor is electrically connected to the data acquisition device; The cylindrical mirror 1, linear array sensor 1, beam splitter prism 1, cylindrical mirror 2, linear array sensor 2 and the cylindrical mirror 3, linear array sensor 3, beam splitter prism 2, cylindrical mirror 4, linear array sensor 4 respectively constitute two two-dimensional displacement sensors, and the two two-dimensional displacement sensors jointly image the point light source, and the two two-dimensional displacement sensors constitute a three-dimensional displacement sensor.

6. A multi-point anti-interference deformation measurement method based on stroboscope energy spectrum, the method is implemented based on the multi-point anti-interference deformation measurement device based on stroboscope energy spectrum according to claim 1, characterized in that: The following steps are involved: S1. Fix F point light sources with different stroboscopic frequencies f(i) at the deformation interest points of the target to be measured. If the target to be measured has multiple target planes to be measured, ensure that there are at least two point light sources in each target plane to be measured. The point light sources are active cursors. S2. Select two characteristic active cursors, which are located in the same target plane and at a certain distance from each other in the direction of deformation to be measured, and measure the distance d1 between the two active cursors in the target plane and in the direction of deformation to be measured using a standard measuring tool; S3. If the target to be measured has W different target planes, repeat S2 to measure the distance dw between the two active cursors in the direction of deformation to be measured in the wth different target plane to be measured; S4. The measuring device is aligned with the target to be measured, the linear array sensor 1 is parallel to the deformation direction to be measured, and F active cursors are simultaneously focused on the linear array sensor 1 through the cylindrical mirror 1; S5, collecting pixel values ​​corresponding to P pixels in a row of the linear array sensor; S6, repeat S5, collecting N×P pixel values ​​corresponding to N rows of P pixels of the linear array sensor; S7. Collect the P-th pixel into N×P pixel values ​​and perform frequency domain analysis based on short-time Fourier transform to obtain the energy spectrum of each pixel. S8. Searching for the energy value corresponding to the stroboscopic frequency f(i) of the i-th active cursor on each pixel energy spectrum signal; S9, calculating the displacement value corresponding to the i-th active cursor strobe frequency f(i) according to the energy spectrum signal of each pixel; S10. Repeat steps S5 to S9 to obtain F time-frequency displacement sequences D(i, t) of active cursors with different strobe frequencies f(i).

7. The multi-light-spot anti-torsion deformation measurement method based on stroboscopic energy spectrum according to claim 6 is characterized in that: In step S4, the linear array sensor 1 is focused, and the busbar of the cylindrical mirror 1 is perpendicular to the pixel arrangement direction of the linear array sensor 1.

8. The multi-light-spot anti-torsion deformation measurement method based on stroboscopic energy spectrum according to claim 6 is characterized in that: The step S7 specifically includes the following steps: S71, read in N pixel values ​​corresponding to the p-th pixel; S72, using windowing to collect the signal X(p,n) from each pixel point, to obtain the mth windowed signal X m (p, n); S73, the pixel signal X after windowing m (p, n) performs short-time Fourier transform to obtain the corresponding signal spectrum FT m (p, k); S74, transform the signal spectrum FT m (p, k) takes the absolute value to get the linear spectrum S m (p, k); S75, the linear spectrum S m The square of the modulus of (p, k) gives the energy E m (p, k).

9. The multi-light-spot anti-torsion deformation measurement method based on stroboscopic energy spectrum according to claim 8, characterized in that: In step S8, the energy spectrum E of each pixel is m (p, k), search along the frequency axis for the maximum energy value e corresponding to F strobe frequencies f(i) m (p, i).

10. The multi-light-spot anti-torsion deformation measurement method based on stroboscopic energy spectrum according to claim 6, characterized in that: The step S9 specifically includes the following steps: S91, for F different stroboscopic frequencies f(i), the energy value e of each pixel corresponding to the stroboscopic frequency f(i) is m (i) Synthesize F sequences Y according to the original pixel order of the image sensor m (p, i); S92, adaptive estimation sequence Y m Energy threshold T(i) of (p, i); S93, sequence Y m The grayscale values ​​of pixels in (p, i) that are less than the energy threshold T(i) are set to 0, and the grayscale values ​​of pixels that are greater than the energy threshold are retained as the original values, and the sequence Y is regenerated. m '(p, i); S94, using the grayscale centroid method, calculate the corresponding sequence Y of all stroboscopic frequencies f(i) m '(p, i)'s center of gravity position sub-pixel value C(i); S95, searching for the distance dw between two characteristic cursors in the deformation direction to be measured in the w-th target plane and their corresponding sub-pixel values ​​of the center of gravity Cw(j) and Cw(k) in all W target planes to be measured; The distance Lw from the linear array sensor 1 to the w-th target plane is calculated based on the focal length of the cylindrical mirror 1, the distance dw between the two characteristic cursors in the target plane, and the corresponding sub-pixel values ​​Cw(j) and Cw(k) of the center of gravity. S96. The corresponding sequence Y of all stroboscopic frequencies f(i) can be obtained by calculating the focal length of the cylindrical mirror and the distance Lw from the linear array sensor to the target plane. m '(p, i) The sub-pixel value C(i) of the center of gravity corresponds to the displacement value D(i).

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