A non-contact three-dimensional displacement measurement method and system based on radar-vision fusion

Abstract

The present invention discloses a non-contact three-dimensional displacement measurement method and system based on radar-vision fusion, which relates to the technical field of structural displacement measurement. For the three-dimensional displacement measurement of a structure based on the fusion of LFMCW millimeter-wave radar technology and computer vision technology, a radar and a camera are used to collect data from the structural measurement points, obtaining the original radar DAC data of the out-of-plane movement of the structure and the image data of the in-plane movement. The ranging frequency modulation method and the phase method are used to analyze the radar original data to obtain the radial distance and radial displacement of the measurement points. At the same time, the DIC sub-pixel matching technology is used to analyze the camera image data to obtain the in-plane position and displacement of the measurement points. Based on the spatial relationship of the data acquisition results of the above two devices and the influence relationship between the data of each dimension of the target point, the rapid acquisition of the three-dimensional displacement at the structural target point is realized.

Description

Technical Field

[0001] The present invention relates to the technical field of structural displacement measurement, and particularly relates to a non-contact three-dimensional displacement measurement method and system based on the fusion of radar and vision. Background Art

[0002] As the most intuitive physical quantity characterizing the structural state, displacement response is the basis for structural health monitoring, subsequent damage identification, safety warning and other work. In the three-dimensional world, the movement of an object belongs to three-dimensional space motion. Therefore, to ensure the safe use of a structure, it is very necessary to realize non-contact three-dimensional displacement vibration monitoring and warning of engineering structures. During the operation of structural facilities such as bridges, buildings, transmission towers, and wind turbine towers, they will be affected by various external loads (wind, seismic loads, etc.) and the aging of their own materials, gradually suffer damage during the service period, and exhibit a certain amplitude of swing, affecting the comfort and safety of the structure. At present, non-contact displacement measurement of engineering structures can be achieved through technologies such as total station, laser vibrometer, GNSS, vision measurement, and microwave radar. The total station and GNSS can achieve three-dimensional displacement measurement of the structure, but their measurement acquisition frequencies are relatively low. The laser vibrometer has extremely high measurement accuracy, but it is easily affected by the surface properties of the measured structure (damage, pollution, roughness). There are challenges in realizing long-term and real-time multi-point synchronous acquisition with the total station and laser vibrometer, while the GNSS measurement point layout is cumbersome, requires attachment to the measured structure and independent power supply, and is difficult to be used in a lightweight manner.

[0003] Both monocular and binocular vision technologies can achieve three-dimensional displacement measurement of target points, but each has its limitations. The out-of-plane measurement accuracy of monocular vision is relatively low. Although binocular vision technology can estimate depth through the parallax information obtained by two cameras and obtain relatively high displacement measurement accuracy, the stereo correlation between the left and right camera images is sometimes difficult to guarantee (the optimal angle of the stereo optical system is about 30°). In addition, when measuring three-dimensional vibration at a long distance, for large outdoor settings, a compromise may be needed between the stereo angle and the baseline (the distance between cameras), which is not conducive to the layout of the equipment. Summary of the Invention

[0004] The purpose of the present invention is to solve the problems of the measurement accuracy of monocular cameras, the stereo matching and baseline distance of binocular cameras, and the mutual interference between multiple radars and the spatial layout during long-distance measurement, and provide a non-contact three-dimensional displacement measurement method and system based on the fusion of radar and vision.

[0005] The purpose of the present invention is achieved through the following technical solutions:

[0006] A non-contact three-dimensional displacement measurement method based on the fusion of radar and vision, the method steps include:

[0007] S1. Data acquisition: Synchronously obtain the first-frame DAC raw data of the radar and the first-frame image data of the camera;

[0008] S2. Establish a coordinate system: Taking the center of the camera imaging plane as the origin, the two sides of the imaging plane as the X and Y directions, and the optical axis as the Z axis, establish a three-dimensional coordinate system for radar-vision fusion measurement, and obtain the position of the radar and the spatial position deviation from the camera;

[0009] The radar-vision fusion is based on radar and computer vision processing;

[0010] S3. Preliminary data processing: Use the frequency-modulated ranging method and the phase method to analyze the first-frame raw data collected by the millimeter-wave radar to obtain the straight-line distance and micro-vibration between the measurement point and the target point;

[0011] For the image data collected by the camera, use DIC sub-pixel matching to realize the identification of the pixel positions and displacements in the X and Y directions at the sub-pixel level within the target point area, and identify the corresponding pixel scale according to the physical size of the marker at the target point in the image data;

[0012] S4. Scale factor calculation: Calculate the scale factor of the first-frame image data according to the physical length of the reference object and the pixel scale;

[0013] S5. Z-direction displacement calibration: Based on the radar vibration measurement principle, according to the influence value of the in-plane and out-of-plane movement of the target point on the radial displacement of the radar, realize the Z-direction displacement calibration;

[0014] Convert the pixel position of the target point into the real physical position, obtain the spatial position angle of the target point, calculate the influence value of the in-plane movement on the radar radial displacement, the change in the radar radial displacement caused by the in-plane movement, and the Z-direction displacement value;

[0015] S6. X and Y direction displacement calibration: Use the calibrated Z-direction displacement value to calibrate the in-plane X and Y direction positions and displacements obtained by DIC, and calculate the calibrated in-plane position and displacement values;

[0016] Use the calibrated Z-direction displacement value to calibrate the X and Y direction positions and displacements, and calculate the calibrated in-plane position and displacement values

[0017] S7. Real-time scale factor calibration: Calculate the projection of the marker in the X-Z plane, the angle between the imaging optical path and the Z direction, and the compensation length, and calculate the new scale factor value after real-time calibration under specific conditions;

[0018] S8. Data calculation and update: Substitute the calibrated parameters into the next frame of data, repeat steps S5 to S7, complete the displacement calibration and scale factor calibration, complete the calculation of all collected frames, and obtain the real-time three-dimensional displacement value of the target point.

[0019] Further, in step S2, a three-dimensional coordinate system of the radar-vision fusion measurement system is established with the center of the imaging plane at the camera's position as the origin, the two axes of the camera imaging plane as the X and Y directions, and the camera optical axis as the Z axis. The origin of this coordinate system is , and the radar position is set as . The point and the spatial position deviation between the camera is .

[0020] Further, in step S3, the first-frame raw data collected by the radar is parsed to obtain the straight-line distance between the measurement point and the target point and the micro-vibration of the target point obtained based on the phase method. At the same time, for the image data collected by the camera, DIC sub-pixel matching is used to achieve the pixel positions in the X and Y directions at the sub-pixel level within the target point plane and the displacement and identify the corresponding pixel scale according to the actual physical size of the marker at the target point in the image data.

[0021] Further, in step S4, the scale factor calculation is expressed as:

[0022] ;

[0023] where is the physical length of the reference object, is the pixel scale, and is the scale factor.

[0024] Further, in step S5, the displacement of the radar can be composed of two parts. One part is the change in the radial displacement of the radar caused by the in-plane movement of the target point , and the other part is the change in the radial displacement of the radar caused by the out-of-plane movement, denoted as . The displacement measured by the radar in the direction of the line connecting the target point and the measurement point, and the calculation formula is ; according to the influence relationship between the position data in step S3 and the in-plane and out-of-plane movements of the target point on the radar's radial displacement, the displacement check in the Z direction is realized;

[0025] Convert the pixel positions of the target point in the X and Y directions into the true actual physical positions and , expressed as:

[0026] ;

[0027] ;

[0028] Among them, and are the real actual physical position coordinate values, and are the pixel position coordinate values in the X and Y directions, and are the pixel displacement values in the X and Y directions;

[0029] Among them, the spatial position angles of the target points to be obtained include: the origin and its vertical projection point on the target point plane, the distance between them is , the horizontal angle between the radar and the target point is , the vertical angle between the radar and the target point is , the horizontal angle between the camera and the target point is , the vertical angle between the camera and the target point is , expressed as:

[0030] ;

[0031] ;

[0032] ;

[0033] ;

[0034] ;

[0035] Among them, is the radial distance, is the displacement amount in the direction of the line connecting the target point measured by the radar and the measuring point, , is the spatial position deviation coordinate value in the X, Y directions;

[0036] The influence of the movement of the target point in the X and Y planes on the radar radial displacement amount can be expressed as , , expressed as:

[0037] ;

[0038] ;

[0039] Among them, , is the influence value of the movement of the target point in the X and Y planes on the radar radial displacement amount, and are the pixel displacement values in the X and Y directions;

[0040] The superimposed component obtains the radial displacement measured by the radar caused by the in-plane movement of the target surface as:

[0041] ;

[0042] The change in the radar radial displacement caused by the in-plane movement of the target point and the Z-direction displacement value , expressed as:

[0043] ;

[0044] ;

[0045] where the change in the radar radial displacement caused by the in-plane movement, is the Z-direction displacement value.

[0046] Furthermore, in step S6, by the in-plane X-direction and Y-direction positions and displacements , obtained by DIC sub-pixel matching are checked, where the influence value of the Z-direction movement of the target point on the in-plane displacement and , expressed as:

[0047] ;

[0048] ;

[0049] The in-plane position of the target point after checking , expressed as:

[0050] ;

[0051] ;

[0052] where and are the coordinate values of the in-plane position of the target point after checking for and ;

[0053] Calculate the displacement values and after checking in the X and Y directions, expressed as:

[0054] ;

[0055] .

[0056] Further, in step S7, calculate the new scale factor value after real-time verification, specifically:

[0057] Calculate The projection on the X-Z plane :

[0058] ;

[0059] Calculate the angle between the optical path and the Z direction during the imaging process of the marker and :

[0060] ;

[0061] ;

[0062] Calculate the compensation length of the marker and :

[0063] ;

[0064] ;

[0065] Taking the physical length after moving in the Z direction converted to the same pixel length before moving as the condition, calculate the new scale factor after real-time verification value, and the calculation formula is:

[0066] .

[0067] Further, after completing steps S1 to S7, obtain the three-dimensional displacement value of the first frame of data, and update , , parameters, repeat steps S5 to S7, complete the verification of the second frame of data after completion, and so on to complete the data calculation of all acquired frames, and finally obtain the real-time three-dimensional displacement of the target point.

[0068] Provided is a non-contact three-dimensional displacement measurement system based on radar-vision fusion for quickly obtaining the three-dimensional displacement at the structural target point.

[0069] The beneficial effects of the present invention are:

[0070] (1) Fuse the data obtained by radar and vision, make full use of the complementary advantages of the two displacement measurement technologies, and realize the identification of three-dimensional displacement information of structural vibration; it can obtain the displacement data of the structure from multiple directions globally, so as to comprehensively master the operating state of the structure;

[0071] (2)Solve the problems of spatial positioning of target points that are difficult to achieve with a single technology, measurement deviation of radar Z-direction displacement, two-dimensional displacement measurement error of DIC, and uncertainty of scale factors;

[0072] (3)Give full play to the data information obtained by the radar and the camera. Through the spatial relationship between the data and the influence relationship between the data in each dimension, the rapid acquisition of three-dimensional data of target points can be realized based on the existing data, which has the characteristics of fast calculation speed, no need to additionally increase data volume storage, and is easy to be realized by computer programming. Brief Description of the Drawings

[0073] Figure 1 It is a flowchart of a non-contact three-dimensional displacement measurement method based on radar-vision fusion in an embodiment of the present invention;

[0074] Figure 2 It is a schematic diagram of the measurement use of a non-contact three-dimensional displacement measurement method based on radar-vision fusion in an embodiment of the present invention;

[0075] Figure 3 It is a schematic diagram of the calculation principle of the spatial position of target points in an embodiment of the present invention;

[0076] Figure 4 It is a schematic diagram of the Z-direction displacement verification principle in an embodiment of the present invention;

[0077] Figure 5 It is a schematic diagram of the X, Y-direction displacement verification principle in an embodiment of the present invention;

[0078] Figure 6 It is a schematic diagram of the scale factor verification principle in an embodiment of the present invention;

[0079] Figure 7 It is a flowchart of the algorithm of a non-contact three-dimensional displacement measurement method based on radar-vision fusion in an embodiment of the present invention;

[0080] Figure 8 It is the three-dimensional displacement data measured in an embodiment of the present invention. Detailed Embodiment

[0081] Next, the technical solutions of the present invention will be clearly and completely described in conjunction with the embodiments. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative efforts belong to the scope of protection of the present invention.

[0082] As Figure 1As shown in the figure, a non-contact three-dimensional displacement measurement method based on radar-vision fusion is provided to solve the problems of low measurement accuracy in monocular cameras in existing non-contact three-dimensional displacement measurements, difficult setting of stereo matching and baseline distance in binocular cameras, mutual interference between multiple radars, and spatial layout in long-distance measurements, so as to achieve a non-contact three-dimensional displacement measurement technology that can be real-time and highly accurate. In this embodiment, a radar and a camera are used to collect data from structural measurement points, obtaining the original radar DAC data of out-of-plane movement of the structure and the image data of in-plane movement. The radial distance and radial displacement of the measurement points are obtained by analyzing the radar original data through frequency-modulated ranging method and phase method. At the same time, the DIC sub-pixel matching technology is used to analyze the camera image data to obtain the in-plane position and displacement of the measurement points, and based on the spatial relationship of the data acquisition results of the above two devices and the influence relationship between the data of each dimension of the target point, the rapid acquisition of the three-dimensional displacement at the structural target point is realized. The method includes the following steps:

[0083] S1. As Figure 2 shown, taking the center of the imaging plane at the position of the camera as the origin, the two sides of the camera imaging plane as the X and Y directions, and the direction of the camera optical axis as the Z axis, a three-dimensional coordinate system of the radar-vision fusion measurement system is established. The origin of this coordinate system is , and the position of the radar is set as point, The spatial position deviation between this point and the camera is .

[0084] After placing the radar and the camera at a certain spatial position according to the measurement requirements, roughly measure the offset distance between the radar and the imaging center point of the camera with a ruler, and set a special radar-vision fusion target at the measured structural measurement point to obtain accurate detection data. According to Figure 3 , it can be known that the displacement measured by the radar is the radial displacement on the line connecting the target point and the position of the radar. There is a real-time deviation between the directly measured data and the Z direction of the three-dimensional coordinate system of the radar-vision fusion system, and the true Z-direction displacement of the structural vibration cannot be obtained. The DIC technology is generally used to measure the two-dimensional displacement of the target point in the plane. When there is out-of-plane movement of the target point, the imaging position and scale factor of the target point on the camera will change in real time, resulting in deviation in the in-plane displacement measurement of the DIC technology, causing distortion in the X and Y direction displacement measurements in the radar-vision fusion system and unable to reflect the true X and Y direction displacements of the target point. Therefore, in this embodiment, the above problems are solved by fusing the LFMCW millimeter-wave radar technology and the computer vision technology.

[0085] The spatial position and scale factor of the target point are obtained by using the first-frame data of the radar and the camera, and the displacement value directly resolved in the second-frame data is mutually verified through the known spatial position to obtain the true spatial displacement in the coordinate system of the vision fusion system; specifically, it includes the following steps:

[0086] S2. Synchronously acquire the first-frame raw data of the millimeter-wave radar and the first-frame image data collected by the camera, as Figure 3 shown, originally calculate the spatial position and scale factor of the target point;

[0087] S3. Analyze the first-frame raw data collected by the LFMCW millimeter-wave radar using the frequency-modulated ranging method and the phase method to obtain the straight-line distance and micro-vibration between the measurement point and the target point; for the image data collected by the camera, use the DIC technology to realize the sub-pixel-level pixel positions in the X and Y directions within the target point surface , as well as displacement , recognition, and identify the corresponding pixel scale according to the actual physical size of the marker at the target point in the image data.

[0088] S4. According to the physical length of the reference object and the pixel scale obtained in step S3, solve the scale factor in the first-frame image data:

[0089] ;

[0090] S5. According to the vibration measurement principle of the LFMCW millimeter-wave radar, when the target point moves within the plane, it will cause a change in the radar measurement value. Therefore, the displacement of the radar can be composed of two parts. One part is the change in the radial displacement of the radar caused by the in-plane movement of the target, denoted as , and the other part is the change in the radial displacement of the radar caused by the out-of-plane movement, denoted as . The displacement amount in the direction of the line connecting the target point and the measurement point measured by the radar, and the calculation formula is . According to the influence relationship between the position data in S3 and the in-plane and out-of-plane movements of the target point on the radial displacement of the radar, the displacement verification in the Z direction can be realized. Among them, step S5 specifically includes the following sub-steps:

[0091] S5.1. Convert the pixel positions of the target point in the X and Y directions into the true actual physical positions and , and the calculation formula is:

[0092] ;

[0093] ;

[0094] Among them, and is the coordinate value of the real actual physical position, and are the pixel position coordinate values in the X and Y directions, and are the pixel displacement values in the X and Y directions;

[0095] S5.2. As shown in Figure 4 , solve for the spatial position of the target point. The distance between the origin and its vertical projection point on the target point plane is , the horizontal angle between the radar and the target point, the vertical angle between the radar and the target point, the horizontal angle between the camera and the target point, and the vertical angle . Use the following formulas to solve for , , , , respectively:

[0096] ;

[0097] ;

[0098] ;

[0099] ;

[0100] ;

[0101] where, is the radial distance, is the displacement amount in the direction of the line connecting the target point measured by the radar and the measuring point, , is the spatial position deviation coordinate value in the X and Y directions.

[0102] S5.3. The influence of the movement of the target point in the X and Y planes on the radial displacement of the radar can be expressed as , , and can be calculated according to the following formula:

[0103] ;

[0104] ;

[0105] where, , are the influence values of the movement of the target point in the X and Y planes on the radial displacement of the radar, and are the pixel displacement values in the X and Y directions;

[0106] The superimposed component obtains the radial displacement measured by the radar caused by the movement within the target plane which is:

[0107] ;

[0108] S5.4. As Figure 5 shown, the change in the radar radial displacement caused by the movement within the target plane and the Z-direction displacement value can be calculated respectively by the following formulas:

[0109] ;

[0110] ;

[0111] where is the change in the radar radial displacement caused by the in-plane movement, is the Z-direction displacement value.

[0112] S6. As Figure 6 shown, when the target point moves in the Z direction (out of the plane), it will cause changes in its position and scale factor on the camera imaging plane. The verified Z-direction displacement value is used to verify the X and Y direction target point positions and displacements;

[0113] S6.1. Verify the in-plane X and Y direction positions and displacements , obtained by DIC. Among them, the influence values and of the Z-direction movement of the target point on the in-plane displacement are expressed as:

[0114] ;

[0115] ;

[0116] The in-plane position of the verified target point is expressed as:

[0117] ;

[0118] ;

[0119] where and are and The coordinate value of the in-plane position of the verified target point;

[0120] S6.2. The displacement values verified in the X and Y directions and can be calculated by the following formula:

[0121] ;

[0122] ;

[0123] S7. When the target point moves in the Z direction (out of the plane), it will cause a scale factor. For the calculation of this part of the influence, step S7 specifically includes the following sub-steps:

[0124] S7.1. Calculate the projection on the X-Z plane , and the calculation formula is:

[0125] ;

[0126] S7.2. Calculate the angles and between the upper / lower optical path and the Z direction during the imaging process of the marker according to the following formula, and there are:

[0127] ;

[0128] ;

[0129] S7.3. Calculate the compensation lengths and of the marker, and there are:

[0130] ;

[0131] ;

[0132] S7.3. Calculate the new scale factor value after real-time verification on the condition that the physical length after moving in the Z direction is converted to the same pixel length before moving. The calculation formula is:

[0133] ;

[0134] S8. After the above steps are completed, substitute the verified , , into the next frame of data, repeat steps S5 to S7, complete the verification of the next frame of data, and so on to complete the calculation of all the collected frames of data, and finally obtain the real-time three-dimensional displacement of the target point. The calculation flow of this algorithm is as Figure 7 shown.

[0135] As Figure 8 shown, the data separately collected by using LFMCW millimeter-wave radar technology and computational vision technology can accurately measure the three-dimensional displacement information of the target point after being fused and processed by the algorithm of this embodiment.

[0136] The above are only the preferred embodiments of the present invention. It should be understood that the present invention is not limited to the form disclosed herein, should not be regarded as excluding other embodiments, but can be used in various other combinations, modifications and environments, and can be changed within the scope of the concept described herein through the above teachings or the technology or knowledge in related fields. And the changes and modifications made by those skilled in the art without departing from the spirit and scope of the present invention shall fall within the protection scope of the appended claims of the present invention.

Claims

1. A non-contact three-dimensional displacement measurement method based on radar-vision fusion, characterized in that The method steps include: S1. Data acquisition: Synchronously obtain the first-frame DAC raw data of the radar and the first-frame image data of the camera. S2. Establish a coordinate system: Taking the center of the camera imaging plane as the origin, the two sides of the imaging plane as the X and Y directions, and the optical axis as the Z axis, establish a three-dimensional coordinate system for radar-vision fusion measurement, and obtain the position of the radar and the spatial position deviation from the camera. S3. Preliminary data processing: Analyze the first-frame raw data collected by the millimeter-wave radar to obtain the straight-line distance and micro-vibration between the measurement point and the target point. For the image data collected by the camera, use DIC sub-pixel matching to identify the pixel positions and displacements in the X and Y directions at the sub-pixel level within the target point area, and identify the corresponding pixel scale according to the physical size of the marker at the target point in the image data. S4. Scale factor calculation: Calculate the scale factor of the first-frame image data according to the physical length of the reference object and the pixel scale. S5. Z-direction displacement verification: Realize the Z-direction displacement verification according to the influence of the movement of the target point inside and outside the plane on the radial displacement of the radar. Convert the pixel position of the target point into the real physical position, obtain the spatial position angle of the target point, and calculate the change in the radar radial displacement caused by the in-plane movement for verifying the Z-direction displacement value. S6. X and Y direction displacement verification: Use the verified Z-direction displacement value to verify the in-plane X and Y direction positions and displacements obtained by DIC, and calculate the verified in-plane position and displacement values. Use the verified Z-direction displacement value to verify the X and Y direction positions and displacements, and calculate the verified in-plane position and displacement values. S7. Real-time scale factor verification: Calculate the projection of the marker on the X-Z plane, the angle between the imaging optical path and the Z direction, and the compensation length, and calculate the newly verified scale factor value under specific conditions. The specific conditions are: taking the physical length after Z-direction movement converted into the same pixel length before movement as the condition. S8. Data calculation and update: Substitute the verified parameters into the next-frame data, repeat steps S5 to S7, complete the calculation of all collected frames, and obtain the real-time three-dimensional displacement value of the target point.

2. The non-contact three-dimensional displacement measurement method based on radar-vision fusion according to claim 1, wherein In step S2, with the center of the imaging plane at the position of the camera as the origin, the two axes of the camera imaging plane are in the X and Y directions, and the optical axis of the camera is the Z axis to establish a three-dimensional coordinate system for the radar-vision fusion measurement system. The origin of this coordinate system is , and the position of the radar is set as point, The spatial position deviation between the point and the camera is .

3. The non-contact three-dimensional displacement measurement method based on thunder and vision fusion according to claim 2, characterized in that In step S3, the first frame of raw data collected by the radar is parsed to obtain the straight-line distance between the measurement point and the target point and the micro-vibration of the target point obtained based on the phase method ; at the same time, for the image data collected by the camera, DIC sub-pixel matching is used to achieve the pixel positions in the X and Y directions at the sub-pixel level within the target point surface 、 and the displacement 、 are identified, and the corresponding pixel scale is identified according to the actual physical size of the marker at the target point in the image data.

4. A non-contact three-dimensional displacement measurement method based on radar-vision fusion according to claim 3, characterized in that, In step S4, the scale factor calculation is expressed as: ; where is the physical length of the reference object, is the pixel scale, is the scale factor.

5. A non-contact three-dimensional displacement measurement method based on radar-vision fusion according to claim 4, characterized in that In step S5, the displacement of the radar consists of two parts. One part is the change in the radial displacement of the radar caused by the in-plane movement of the target point , and the other part is the change in the radial displacement of the radar caused by the out-of-plane movement, denoted as . The displacement of the target point measured by the radar in the direction of the line connecting the target point and the measurement point , and the calculation formula is ; According to the position data in step S3 and the influence relationship of the in-plane and out-of-plane movements of the target point on the radial displacement of the radar, the displacement check in the Z direction is realized; Convert the pixel positions of the target point in the X and Y directions into actual physical positions and , expressed as: ; ; where and are the coordinate values of the actual physical positions, and are the coordinate values of the pixel positions in the X and Y directions, and are the pixel displacement values in the X and Y directions; Among them, the spatial position angles of the target points to be obtained include: the origin and its vertical projection point on the target point plane The distance between them is , the horizontal included angle between the radar and the target point is , the vertical included angle between the radar and the target point is , the horizontal included angle between the camera and the target point is , the vertical included angle between the camera and the target point is , expressed as: ; ; ; ; ; where is the radial distance, is the displacement amount in the direction of the line connecting the target point measured by the radar and the measuring point, , is the spatial position deviation coordinate value in the X and Y directions; The influence of the movement of the target point in the X and Y planes on the radial displacement of the radar is expressed as , , expressed as: ; ; where , is the influence value of the movement of the target point in the X and Y planes on the radial displacement of the radar; The superimposed component obtains the radial displacement measured by the radar caused by the in-plane movement of the target surface is: ; the change in the radar radial displacement caused by the in-plane movement of the target point and the Z-direction displacement value , expressed as: ; ; where is the change in the radar radial displacement caused by the in-plane movement, is the Z-direction displacement value.

6. The non-contact three-dimensional displacement measurement method based on thunder and vision fusion according to claim 5 is characterized in that, In step S6, by the in-plane X and Y positions and displacements , obtained by DIC sub-pixel matching are checked. Among them, the influence value of the Z-direction movement of the target point on the in-plane displacement and ; ; The in-plane position of the target point after checking is expressed as: ; ; Among them, and are and the coordinate values of the in-plane positions of the target points after checking; Calculate the displacement values after checking in the X and Y directions and , expressed as: ; .

7. A non-contact three-dimensional displacement measurement method based on radar-vision fusion according to claim 6, characterized in that In step S7, calculating the newly verified scale factor value specifically is: Calculation Projection on the X-Z plane : ; Calculate the angle between the optical path and the Z direction during the imaging of the calculation marker and : ; ; Calculate the compensation length of the marker and : ; ; Calculate the new scale factor after real-time verification on the condition that the physical length after moving in the Z direction is converted to the equivalent pixel length before moving value, and the calculation formula is: 。 8. A non-contact three-dimensional displacement measurement method based on radar-vision fusion according to claim 7, characterized in that After completing steps S1 to S7, the three-dimensional displacement value of the first frame of data is obtained, and , , and parameters are updated according to the calculation results of the first frame. Steps S5 to S7 are repeated to complete the verification of the second frame of data, and so on to complete the data calculation of all acquired frames, and finally the real-time three-dimensional displacement of the target point is obtained. , , parameters, repeat steps S5 to S7, complete the verification of the second frame of data after completion, and so on to complete the data calculation of all acquired frames, and finally obtain the real-time three-dimensional displacement of the target point.

9. A non-contact three-dimensional displacement measurement system based on the fusion of radar and vision, characterized in that, For implementing a non-contact three-dimensional displacement measurement method based on radar-vision fusion according to any one of claims 1 to 8.

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