CN115727770A - Speckle shearing interference-based method for measuring out-of-plane displacement of curved surface object - Google Patents

Speckle shearing interference-based method for measuring out-of-plane displacement of curved surface object Download PDF

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CN115727770A
CN115727770A CN202211454063.5A CN202211454063A CN115727770A CN 115727770 A CN115727770 A CN 115727770A CN 202211454063 A CN202211454063 A CN 202211454063A CN 115727770 A CN115727770 A CN 115727770A
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speckle
plane displacement
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CN115727770B (en
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彭艳华
牛方明
闫奕樸
王文举
兰海贝
黄德龙
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Guilin University of Electronic Technology
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Abstract

本发明涉及一种基于散斑剪切干涉的计量曲面物体离面位移方法，步骤包括：1、获被测物调制后的正弦条纹图并进行灰度处理；2、得到绝对相位信息,获取物体相对相机的三维坐标,获取物体相对相机的三维坐标；3、计算出被测物表面法向量相对CCD相机光轴的夹角

Figure 100004_DEST_PATH_IMAGE002
；4、采集被测物表面变形前后的散斑包裹相位图并进行灰度处理和滤波处理；5、计算所测得的表面离面位移信息；6、建立激光散斑所测的离面位移测量值与被测物体表面实际变形的离面位移
Figure 100004_DEST_PATH_IMAGE004
之间的几何关系；7、求得实际的离面位移
Figure DEST_PATH_IMAGE006
；本发明采用剪切散斑干涉与数字条纹投影相结合，以检测出曲面（斜面）物体内部缺陷的同时，并能获取其离面位移信息用于分析其缺陷属性，有利于曲面物体内部缺陷属性的评估。

Figure 202211454063

The invention relates to a method for measuring the out-of-plane displacement of a curved surface object based on speckle shear interference. Relative to the three-dimensional coordinates of the camera, obtain the three-dimensional coordinates of the object relative to the camera; 3. Calculate the angle between the surface normal vector of the measured object and the optical axis of the CCD camera

Figure 100004_DEST_PATH_IMAGE002
;4. Collect the speckle wrapping phase map before and after the surface deformation of the measured object and perform grayscale processing and filtering; 5. Calculate the measured surface out-of-plane displacement information; 6. Establish the out-of-plane displacement measured by laser speckle The out-of-plane displacement between the measured value and the actual deformation of the surface of the measured object
Figure 100004_DEST_PATH_IMAGE004
7. Obtain the actual out-of-plane displacement
Figure DEST_PATH_IMAGE006
; The present invention combines shear speckle interference and digital fringe projection to detect internal defects of curved (inclined) objects, and at the same time obtain its out-of-plane displacement information for analyzing its defect attributes, which is beneficial to the internal defects of curved objects property evaluation.

Figure 202211454063

Description

一种基于散斑剪切干涉的计量曲面物体离面位移方法A Method of Measuring Out-of-Plane Displacement of Curved Surface Objects Based on Speckle Shear Interferometry

技术领域technical field

本发明设计光学测量检测领域，具体涉及一种基于散斑剪切干涉的计量曲面物体离面位移方法。The invention relates to the field of optical measurement and detection, and specifically relates to a method for measuring the out-of-plane displacement of a curved surface object based on speckle shear interference.

背景技术Background technique

激光散斑剪切干涉技术作为光测力学技术，具有高精度、非接触、全场、实时测量等特点，其优异的抗震性能使其广泛应用在位移测量、应变测量、震动测量、变形测量、温度测量以及工程材料的内部缺陷检测等领域，利用激光散斑剪切技术测量因内部缺陷引起的面外变形量来间接获取缺陷属性是对材料性能判断的方法之一。Laser speckle shearing interferometry technology, as a photomechanical technology, has the characteristics of high precision, non-contact, full-field, real-time measurement, etc. Its excellent seismic performance makes it widely used in displacement measurement, strain measurement, vibration measurement, deformation measurement, In the fields of temperature measurement and internal defect detection of engineering materials, using laser speckle shearing technology to measure the out-of-plane deformation caused by internal defects to indirectly obtain defect attributes is one of the methods for judging material properties.

激光散斑剪切干涉技术通过采集被测物形变前后的散斑图做差处理得到离面位移，该离面位移是沿相机光轴方向，对于曲面（斜面）物体的离面位移测量，被测物体每点的变形方向不一定平行于光轴，所测得的离面位移并不是曲面每点实际的变形量。上海大学李晓东等人通过构建三种波长不同的激光测量光路，使用一台CCD彩色相机一次记录三种光路获得的散斑干涉图像来测量物体的三维变形，但该方法光路复杂，同时需要多种激光光源，操作较为繁琐；山东师范大学孙勇明等人将数字散斑相关法和电子散斑干涉术结合在一起测量物体的三维变形，该方法只能测量平面物体的三维变形；上海交通大学李鹏飞等人，利用激光散斑偏转法求取曲面物体的三维形貌，并结合曲面变形前后的散斑图获得离面形变信息，但是该方法需要高精度的光源偏转仪器，抗干扰性能较差。The laser speckle shearing interference technology obtains the out-of-plane displacement by collecting the speckle images before and after the deformation of the measured object, and the out-of-plane displacement is along the optical axis of the camera. The deformation direction of each point of the measured object is not necessarily parallel to the optical axis, and the measured out-of-plane displacement is not the actual deformation of each point on the surface. Li Xiaodong of Shanghai University and others built three laser measurement optical paths with different wavelengths, and used a CCD color camera to record the speckle interference images obtained by the three optical paths at one time to measure the three-dimensional deformation of the object. Laser light source, the operation is relatively cumbersome; Sun Yongming of Shandong Normal University and others combined digital speckle correlation method and electronic speckle interferometry to measure the three-dimensional deformation of objects. This method can only measure three-dimensional deformation of planar objects; Li Pengfei of Shanghai Jiaotong University et al. used the laser speckle deflection method to obtain the three-dimensional shape of the curved surface object, and combined the speckle images before and after the surface deformation to obtain the out-of-plane deformation information. However, this method requires a high-precision light source deflection instrument and has poor anti-interference performance.

因此，提出一种通过抗干扰性能强的三维形貌和离面形变的组合测量，得到对曲面、斜面的面外形变的计量方法具有十分重要的意义。Therefore, it is of great significance to propose a combined measurement of three-dimensional shape and out-of-plane deformation with strong anti-interference performance to obtain the measurement method for the surface deformation of curved surfaces and inclined surfaces.

发明内容Contents of the invention

针对上述现有问题，本发明提供了一种基于散斑剪切干涉的计量曲面物体离面位移方法，采用剪切散斑干涉与数字条纹投影相结合，以检测出曲面（斜面）物体内部缺陷的同时，并能获取其离面位移信息用于分析其缺陷属性。In view of the above existing problems, the present invention provides a method for measuring the out-of-plane displacement of curved surface objects based on speckle shear interference, which uses the combination of shear speckle interference and digital fringe projection to detect internal defects of curved (slope) objects At the same time, its out-of-plane displacement information can be obtained to analyze its defect properties.

为了实现上述目的，本发明采用的技术方案为：In order to achieve the above object, the technical scheme adopted in the present invention is:

一种基于散斑剪切干涉的计量曲面物体离面位移方法，包括如下步骤：A method for measuring the out-of-plane displacement of a curved surface object based on speckle shear interference, comprising the following steps:

S1、投影仪投出正弦条纹到被测物表面，由CCD相机采集受被测物调制后的正弦条纹图并进行灰度处理；S1. The projector casts sinusoidal fringes to the surface of the measured object, and the CCD camera collects the sinusoidal fringe pattern modulated by the measured object and performs grayscale processing;

S2、利用相移法对CCD相机采集的受调制的投影条纹图像提取包裹相位，结合多频外插法进行解包裹计算，得到绝对相位信息,获取物体相对相机的三维坐标,结合相机与标定的投影系统参数求取物体相对相机的三维坐标；S2. Use the phase shift method to extract the wrapped phase from the modulated projected fringe image collected by the CCD camera, combine the multi-frequency extrapolation method to perform unwrapped calculations, obtain absolute phase information, and obtain the three-dimensional coordinates of the object relative to the camera. Combine the camera with the calibrated Projection system parameters to obtain the three-dimensional coordinates of the object relative to the camera;

S3、利用PCL(Point Cloud Learning)对重建的点云数据集中的三维模型进行法向量估计，并计算出被测物表面法向量相对CCD相机光轴的夹角

Figure DEST_PATH_IMAGE002
；S3. Use PCL (Point Cloud Learning) to estimate the normal vector of the 3D model in the reconstructed point cloud dataset, and calculate the angle between the surface normal vector of the measured object and the optical axis of the CCD camera
Figure DEST_PATH_IMAGE002
;

S4、激光器投射激光到被测物表面，通过对被测物施加外部载荷，由CCD相机分别采集被测物表面变形前后的散斑包裹相位图并进行灰度处理和滤波处理；S4. The laser projects laser light onto the surface of the measured object, and by applying an external load to the measured object, the CCD camera collects the speckle wrapping phase images before and after the surface deformation of the measured object, and performs grayscale processing and filtering processing;

S5、利用相移法对CCD相机采集的散斑包裹相位图提取相位，并利用最小二乘解包裹算法对散斑包裹相位图进行相位展开，获得解包后相位分布信息，代入波长、剪切量等参数计算得到所测得的表面离面位移信息（即光程差

Figure DEST_PATH_IMAGE004
）；S5. Use the phase shift method to extract the phase from the speckle-wrapped phase map collected by the CCD camera, and use the least squares unwrapping algorithm to perform phase unwrapping on the speckle-wrapped phase map to obtain the unwrapped phase distribution information, which is substituted into the wavelength, shear Calculate the measured surface out-of-plane displacement information (that is, the optical path difference
Figure DEST_PATH_IMAGE004
);

S6、建立激光散斑所测的离面位移测量值（即光程差

Figure DEST_PATH_IMAGE004A
）与被测物体表面实际变形的离面位移值
Figure DEST_PATH_IMAGE007
之间的几何关系；S6. Establish the measured value of the out-of-plane displacement measured by the laser speckle (that is, the optical path difference
Figure DEST_PATH_IMAGE004A
) and the out-of-plane displacement value of the actual deformation of the surface of the measured object
Figure DEST_PATH_IMAGE007
the geometric relationship between

S7、根据S6中的几何关系，利用被测物体表面法向量相对CCD相机光轴的夹角

Figure DEST_PATH_IMAGE009
对散斑剪切干涉所测得的离面位移信息进行修正，求得实际的离面位移
Figure DEST_PATH_IMAGE011
。S7. According to the geometric relationship in S6, use the angle between the surface normal vector of the measured object and the optical axis of the CCD camera
Figure DEST_PATH_IMAGE009
Correct the out-of-plane displacement information measured by speckle shear interference to obtain the actual out-of-plane displacement
Figure DEST_PATH_IMAGE011
.

作为优选的技术方案：As a preferred technical solution:

如上所述的一种基于散斑剪切干涉的计量曲面物体离面位移方法，在步骤S2中，求解绝对相位信息的过程如下：As mentioned above, a method for measuring the out-of-plane displacement of a curved surface object based on speckle shear interference, in step S2, the process of solving the absolute phase information is as follows:

相机采集的相位条纹图的数学表达式为：The mathematical expression of the phase fringe pattern collected by the camera is:

Figure DEST_PATH_IMAGE013
Figure DEST_PATH_IMAGE013

式中，

Figure DEST_PATH_IMAGE015
为条纹光强，
Figure DEST_PATH_IMAGE017
为图像像素坐标，
Figure DEST_PATH_IMAGE019
为背景光强分布，
Figure DEST_PATH_IMAGE021
为光强调制度，
Figure DEST_PATH_IMAGE023
为待求相位，
Figure DEST_PATH_IMAGE025
为相移量，其中
Figure DEST_PATH_IMAGE027
。In the formula,
Figure DEST_PATH_IMAGE015
is the fringe intensity,
Figure DEST_PATH_IMAGE017
is the image pixel coordinates,
Figure DEST_PATH_IMAGE019
is the background light intensity distribution,
Figure DEST_PATH_IMAGE021
For light accentuation system,
Figure DEST_PATH_IMAGE023
For the desired phase,
Figure DEST_PATH_IMAGE025
is the amount of phase shift, where
Figure DEST_PATH_IMAGE027
.

使用相移法求取相位

Figure DEST_PATH_IMAGE029
，解得：Find the phase using the phase shift method
Figure DEST_PATH_IMAGE029
,Solutions have to:

Figure DEST_PATH_IMAGE031
；
Figure DEST_PATH_IMAGE031
;

利用多频外插方法对其相位展开得到绝对相位

Figure DEST_PATH_IMAGE033
，相位分布与高度关系为：Using the multi-frequency extrapolation method to expand its phase to obtain the absolute phase
Figure DEST_PATH_IMAGE033
, the relationship between phase distribution and height is:

Figure DEST_PATH_IMAGE035
；
Figure DEST_PATH_IMAGE035
;

式中：

Figure DEST_PATH_IMAGE037
为物体的高度信息分布，
Figure DEST_PATH_IMAGE039
为被测物的相位变化量，
Figure DEST_PATH_IMAGE041
为相机光心到参考平面的距离，
Figure DEST_PATH_IMAGE043
为投影仪光源到相机光心的距离，
Figure DEST_PATH_IMAGE045
为投影条纹间距。In the formula:
Figure DEST_PATH_IMAGE037
is the height information distribution of the object,
Figure DEST_PATH_IMAGE039
is the phase change of the measured object,
Figure DEST_PATH_IMAGE041
is the distance from the optical center of the camera to the reference plane,
Figure DEST_PATH_IMAGE043
is the distance from the light source of the projector to the optical center of the camera,
Figure DEST_PATH_IMAGE045
is the projected fringe spacing.

如上所述的一种基于散斑剪切干涉的计量曲面物体离面位移方法，在步骤S3中，对点云数据集进行法向量估计，基于局部平面拟合，创建任一点临近元素的协方差矩阵，求其最小特征值对应的特征向量即为该局部平面法向量

Figure DEST_PATH_IMAGE047
；对于每一个点
Figure DEST_PATH_IMAGE049
，其对应的协方差矩阵
Figure DEST_PATH_IMAGE051
为:As described above, a method for measuring the out-of-plane displacement of curved surface objects based on speckle shearing interference, in step S3, the normal vector estimation is performed on the point cloud dataset, and the covariance of adjacent elements at any point is created based on local plane fitting Matrix, the eigenvector corresponding to its minimum eigenvalue is the local plane normal vector
Figure DEST_PATH_IMAGE047
; for each point
Figure DEST_PATH_IMAGE049
, and its corresponding covariance matrix
Figure DEST_PATH_IMAGE051
for:

Figure DEST_PATH_IMAGE053
；
Figure DEST_PATH_IMAGE053
;

Figure DEST_PATH_IMAGE055
；
Figure DEST_PATH_IMAGE055
;

式中，

Figure DEST_PATH_IMAGE057
是点
Figure DEST_PATH_IMAGE049A
邻近点的数目，
Figure DEST_PATH_IMAGE060
表示最邻近元素的三维质心，
Figure DEST_PATH_IMAGE062
分别表示为协方差矩阵的第
Figure DEST_PATH_IMAGE064
个特征值和特征向量，当法向方向朝相机方向时，满足
Figure DEST_PATH_IMAGE066
,
Figure DEST_PATH_IMAGE068
为点云数据集的视点。In the formula,
Figure DEST_PATH_IMAGE057
is the point
Figure DEST_PATH_IMAGE049A
the number of neighboring points,
Figure DEST_PATH_IMAGE060
represents the 3D centroid of the nearest neighbor element,
Figure DEST_PATH_IMAGE062
Respectively expressed as the first covariance matrix
Figure DEST_PATH_IMAGE064
eigenvalues and eigenvectors, when the normal direction is towards the camera direction, satisfy
Figure DEST_PATH_IMAGE066
,
Figure DEST_PATH_IMAGE068
is the viewpoint of the point cloud dataset.

如上所述的一种基于散斑剪切干涉的计量曲面物体离面位移方法，在步骤S3中，计算被测物表面法向量相对CCD相机光轴的夹角

Figure DEST_PATH_IMAGE002A
：As mentioned above, a method for measuring the out-of-plane displacement of a curved surface object based on speckle shear interference, in step S3, calculate the angle between the surface normal vector of the measured object and the optical axis of the CCD camera
Figure DEST_PATH_IMAGE002A
:

Figure DEST_PATH_IMAGE071
；
Figure DEST_PATH_IMAGE071
;

式中，

Figure DEST_PATH_IMAGE047A
为被测物表面法向量，
Figure DEST_PATH_IMAGE074
为CCD相机光轴方向的单位向量。In the formula,
Figure DEST_PATH_IMAGE047A
is the surface normal vector of the measured object,
Figure DEST_PATH_IMAGE074
is the unit vector in the direction of the optical axis of the CCD camera.

如上所述的一种基于散斑剪切干涉的计量曲面物体离面位移方法，在步骤S5中，通过对散斑包裹相位图进行解包裹计算，得到相位分布信息

Figure DEST_PATH_IMAGE076
和离面位移导数
Figure DEST_PATH_IMAGE078
（
Figure DEST_PATH_IMAGE080
方向剪切）之间的关系：In the method for measuring the out-of-plane displacement of a curved surface object based on speckle shear interference as described above, in step S5, the phase distribution information is obtained by unwrapping and calculating the speckle wrapped phase map
Figure DEST_PATH_IMAGE076
and out-of-plane displacement derivatives
Figure DEST_PATH_IMAGE078
(
Figure DEST_PATH_IMAGE080
Direction shear) relationship between:

Figure DEST_PATH_IMAGE082
Figure DEST_PATH_IMAGE082

对其积分求解离面位移即光程差

Figure DEST_PATH_IMAGE084
；Solve the out-of-plane displacement, that is, the optical path difference by its integral
Figure DEST_PATH_IMAGE084
;

式中，

Figure DEST_PATH_IMAGE086
为沿
Figure DEST_PATH_IMAGE080A
方向的剪切量，
Figure DEST_PATH_IMAGE089
为CCD相机与光源的夹角，
Figure DEST_PATH_IMAGE091
为激光波长。In the formula,
Figure DEST_PATH_IMAGE086
for along
Figure DEST_PATH_IMAGE080A
The amount of shear in the direction,
Figure DEST_PATH_IMAGE089
is the angle between the CCD camera and the light source,
Figure DEST_PATH_IMAGE091
is the laser wavelength.

如上所述的一种基于散斑剪切干涉的计量曲面物体离面位移方法，在步骤S6中，激光剪切散斑法测量离面位移信息是将变化前后的相位信息进行相减，得到光轴方向的离面位移信息（即光程差），而物体发生微小离面形变时其方向是沿表面法向量方向，故所测得光程差

Figure DEST_PATH_IMAGE004AA
与实际变形量
Figure DEST_PATH_IMAGE007A
之间的关系为：As mentioned above, a method for measuring the out-of-plane displacement of a curved surface object based on speckle shearing interference, in step S6, the laser shearing speckle method measures the out-of-plane displacement information by subtracting the phase information before and after the change to obtain the light The out-of-plane displacement information in the axial direction (that is, the optical path difference), and when the object undergoes a small out-of-plane deformation, its direction is along the direction of the surface normal vector, so the measured optical path difference
Figure DEST_PATH_IMAGE004AA
and actual deformation
Figure DEST_PATH_IMAGE007A
The relationship between is:

Figure DEST_PATH_IMAGE095
。
Figure DEST_PATH_IMAGE095
.

如上所述的一种基于散斑剪切干涉的计量曲面物体离面位移方法，在步骤S5中，对散斑包裹相位图进行解包裹计算的过程为：As mentioned above, a method for measuring the out-of-plane displacement of a curved surface object based on speckle shear interference, in step S5, the process of unwrapping and calculating the speckle wrapping phase map is as follows:

变形前的散斑图的光强表达式为

Figure DEST_PATH_IMAGE097
，The light intensity expression of the speckle pattern before deformation is
Figure DEST_PATH_IMAGE097
,

Figure DEST_PATH_IMAGE099
；
Figure DEST_PATH_IMAGE099
;

变形后的光强表达式

Figure DEST_PATH_IMAGE101
为：Transformed light intensity expression
Figure DEST_PATH_IMAGE101
for:

Figure DEST_PATH_IMAGE103
；
Figure DEST_PATH_IMAGE103
;

将变形前后的条纹图进行相减得到四幅相位包裹图

Figure DEST_PATH_IMAGE105
，Subtract the fringe images before and after deformation to obtain four phase wrapping images
Figure DEST_PATH_IMAGE105
,

Figure DEST_PATH_IMAGE107
；
Figure DEST_PATH_IMAGE107
;

根据四部相移原理，得到变形前后相位变化量：According to the four-part phase shift principle, the phase change before and after deformation is obtained:

Figure DEST_PATH_IMAGE109
；
Figure DEST_PATH_IMAGE109
;

需要对其进行解包裹处理得到展开相位图，得到相位分布信息

Figure DEST_PATH_IMAGE076A
和离面位移导数
Figure DEST_PATH_IMAGE112
（
Figure DEST_PATH_IMAGE080AA
方向剪切）之间的关系为：It needs to be unwrapped to get the unfolded phase map and get the phase distribution information
Figure DEST_PATH_IMAGE076A
and out-of-plane displacement derivatives
Figure DEST_PATH_IMAGE112
(
Figure DEST_PATH_IMAGE080AA
The relationship between shear direction) is:

Figure DEST_PATH_IMAGE082A
Figure DEST_PATH_IMAGE082A

对其积分求解离面位移即光程差

Figure DEST_PATH_IMAGE084A
。Solve the out-of-plane displacement, that is, the optical path difference by its integral
Figure DEST_PATH_IMAGE084A
.

如上所述的一种基于散斑剪切干涉的计量曲面物体离面位移方法，在步骤S1和S4中，均由同一CCD相机（或光轴平行的两组CCD相机）分别获取被调制的正弦条纹图和散斑包裹相位图，投影仪投出正弦条纹到被测物体表面，光路经由透镜、剪切干涉系统被CCD相机采集，此时剪切干涉系统未处于干涉状态，计算机模块处理得到被测物的三维信息，激光发生器发出的激光阵列经扩束装置后照射在被测物表面，光路由剪切干涉系统分为两束光在空间上形成干涉，由CCD相机采集到散斑包裹相位图。As mentioned above, a method for measuring the out-of-plane displacement of a curved surface object based on speckle shearing interference, in steps S1 and S4, the same CCD camera (or two groups of CCD cameras with parallel optical axes) respectively acquires the modulated sinusoidal The fringe pattern and the speckle wrapped phase pattern, the projector casts sinusoidal fringes to the surface of the measured object, the optical path is collected by the CCD camera through the lens and the shearing interference system. At this time, the shearing interference system is not in the interference state, and the computer module processes it For the three-dimensional information of the measured object, the laser array emitted by the laser generator is irradiated on the surface of the measured object after passing through the beam expander. phase diagram.

本发明还提供一种用于实现上述方法的复用光路系统，如图2所示，所述系统包括扩束镜、投影仪、剪切干涉仪、CCD相机、激光器发生器、计算机模块、反光镜、调节镜、相移器，所述计算机能够控制投影仪和激光器发生器向被测物体表面投影相移编码条纹和激光；所述CCD相机用于捕获被测物表面放射形成的图像，发送给所述计算机生成调制图片组并排序，所述计算机还用于对所述的调制图像进行相位展开，实现对被测物体表面的点云数据重建和被测物表面的离面变形重构，利用点云数据获取被测物表面法向量与光轴的夹角来对离面位移值进行修正。The present invention also provides a multiplexing optical path system for realizing the above method, as shown in Figure 2, the system includes a beam expander, a projector, a shear interferometer, a CCD camera, a laser generator, a computer module, a reflective Mirror, adjusting mirror, phase shifter, the computer can control the projector and the laser generator to project phase-shift coded stripes and laser light on the surface of the measured object; the CCD camera is used to capture the image formed by radiation on the surface of the measured generating and sorting the modulated picture group for the computer, and the computer is also used to phase unwrap the modulated images to realize point cloud data reconstruction of the surface of the measured object and out-of-plane deformation reconstruction of the surface of the measured object, The angle between the surface normal vector of the measured object and the optical axis is obtained by using the point cloud data to correct the out-of-plane displacement value.

与现有技术相比，本发明的有益效果为：Compared with prior art, the beneficial effect of the present invention is:

本发明通过结合面结构光的三维测量和剪切散斑干涉的离面位移测量技术，控制调节镜来实现面结构光与剪切散斑系统的切换，能够实现对三维形貌和离面形变的组合测量，将三维形貌的法向量信息引入离面位移的测量中，实现测量曲面物体的离面位移信息，本发明具有结构简单、能够实现快速测量、抗干扰能力强，能够实现全场、非接触测量。The present invention combines the three-dimensional measurement of surface structured light and the out-of-plane displacement measurement technology of shear speckle interference, and controls the adjustment mirror to realize the switching between surface structured light and shear speckle system, which can realize the three-dimensional shape and out-of-plane deformation The combined measurement of the three-dimensional shape normal vector information is introduced into the measurement of the out-of-plane displacement to realize the measurement of the out-of-plane displacement information of the curved surface object. The invention has the advantages of simple structure, fast measurement, strong anti-interference ability, and full field , Non-contact measurement.

附图说明Description of drawings

图1为本发明的方法流程示意图；Fig. 1 is a schematic flow chart of the method of the present invention;

图2为本发明的离面位移测量方法中的装置及光路系统示意图；Fig. 2 is a schematic diagram of the device and the optical path system in the out-of-plane displacement measuring method of the present invention;

图3为被测物体变形时离面位移与CCD相机所测离面位移的几何关系示意图；Fig. 3 is a schematic diagram of the geometric relationship between the out-of-plane displacement and the out-of-plane displacement measured by the CCD camera when the measured object is deformed;

图4为CCD相机采集的条纹光栅图；Fig. 4 is the fringe raster image that CCD camera collects;

图5为重建被测物体的三维点云图；Figure 5 is a three-dimensional point cloud image of the reconstructed object to be measured;

图6为加载变形的散斑包裹相位图；Figure 6 is the speckle wrapping phase diagram of loading deformation;

图7为对散斑包裹相位图解包裹得到的相位图；Fig. 7 is the phase diagram obtained by wrapping the speckle wrapping phase diagram;

图8为激光散斑测得的离面位移信息；Figure 8 shows the out-of-plane displacement information measured by laser speckle;

图9为修正后的离面位移信息；Figure 9 shows the corrected out-of-plane displacement information;

图中：1-激光发生器，2-扩束镜，3-被测物表面，4-投影仪，5-计算机模块，6-CCD相机，7-剪切干涉仪，8-反光镜，9-调节镜，10-相移器。In the figure: 1-laser generator, 2-beam expander, 3-surface of object to be measured, 4-projector, 5-computer module, 6-CCD camera, 7-shearing interferometer, 8-mirror, 9 - adjustment mirror, 10 - phase shifter.

具体实施方式Detailed ways

下面结合具体实施方式，进一步阐述本发明。应理解，这些实施例仅用于说明本发明而不用于限制本发明的范围。此外应理解，在阅读了本发明讲授的内容之后，本领域技术人员可以对本发明作各种改动或修改，这些等价形式同样落于本申请所附权利要求书所限定的范围。The present invention will be further described below in combination with specific embodiments. It should be understood that these examples are only used to illustrate the present invention and are not intended to limit the scope of the present invention. In addition, it should be understood that after reading the teachings of the present invention, those skilled in the art can make various changes or modifications to the present invention, and these equivalent forms also fall within the scope defined by the appended claims of the present application.

一种基于散斑剪切干涉的计量曲面物体离面位移方法，如图1所示，步骤如下：A method of measuring the out-of-plane displacement of a curved surface object based on speckle shear interference, as shown in Figure 1, the steps are as follows:

S1、投影仪4投影光栅条纹到被测物体3上，调节调节镜9使剪切干涉仪7不处于干涉状态，CCD相机6采集受被测物调制后的正弦条纹图并进行灰度处理；S1. The projector 4 projects grating fringes onto the measured object 3, adjusts the adjustment mirror 9 so that the shearing interferometer 7 is not in the interference state, and the CCD camera 6 collects the sinusoidal fringe pattern modulated by the measured object and performs grayscale processing;

S2、计算机模块5通过相移法对CCD相机采集的受调制的投影条纹图像提取包裹相位，结合多频外插法进行解包裹计算，得到绝对相位信息，计算机模块5结合相机与标定的投影系统参数求取物体相对相机的三维坐标；S2. The computer module 5 extracts the wrapped phase from the modulated projected fringe image collected by the CCD camera through the phase shift method, and performs unwrapping calculation in combination with the multi-frequency extrapolation method to obtain absolute phase information. The computer module 5 combines the camera and the calibrated projection system Parameters to obtain the three-dimensional coordinates of the object relative to the camera;

其中，求解绝对相位信息的过程如下：Among them, the process of solving the absolute phase information is as follows:

相机采集的相位条纹图的数学表达式为：The mathematical expression of the phase fringe pattern collected by the camera is:

Figure DEST_PATH_IMAGE013A
Figure DEST_PATH_IMAGE013A

式中，

Figure DEST_PATH_IMAGE015A
为条纹光强，
Figure DEST_PATH_IMAGE017A
为图像像素坐标，
Figure DEST_PATH_IMAGE019A
为背景光强分布，
Figure DEST_PATH_IMAGE021A
为光强调制度，
Figure DEST_PATH_IMAGE023A
为待求相位，
Figure DEST_PATH_IMAGE025A
为相移量，其中
Figure DEST_PATH_IMAGE027A
；In the formula,
Figure DEST_PATH_IMAGE015A
is the fringe intensity,
Figure DEST_PATH_IMAGE017A
is the image pixel coordinates,
Figure DEST_PATH_IMAGE019A
is the background light intensity distribution,
Figure DEST_PATH_IMAGE021A
For light accentuation system,
Figure DEST_PATH_IMAGE023A
For the desired phase,
Figure DEST_PATH_IMAGE025A
is the amount of phase shift, where
Figure DEST_PATH_IMAGE027A
;

使用相移法求取相位

Figure DEST_PATH_IMAGE029A
，解得：Find the phase using the phase shift method
Figure DEST_PATH_IMAGE029A
,Solutions have to:

Figure DEST_PATH_IMAGE031A
；
Figure DEST_PATH_IMAGE031A
;

利用多频外插方法对其相位展开得到绝对相位

Figure DEST_PATH_IMAGE033A
，相位分布与高度关系为：Using the multi-frequency extrapolation method to expand its phase to obtain the absolute phase
Figure DEST_PATH_IMAGE033A
, the relationship between phase distribution and height is:

Figure DEST_PATH_IMAGE035A
；
Figure DEST_PATH_IMAGE035A
;

式中：

Figure DEST_PATH_IMAGE037A
为物体的高度信息分布，
Figure DEST_PATH_IMAGE039A
为被测物的相位变化量，
Figure DEST_PATH_IMAGE041A
为相机光心到参考平面的距离，
Figure DEST_PATH_IMAGE043A
为投影仪光源到相机光心的距离，
Figure DEST_PATH_IMAGE045A
为投影条纹间距；In the formula:
Figure DEST_PATH_IMAGE037A
is the height information distribution of the object,
Figure DEST_PATH_IMAGE039A
is the phase change of the measured object,
Figure DEST_PATH_IMAGE041A
is the distance from the optical center of the camera to the reference plane,
Figure DEST_PATH_IMAGE043A
is the distance from the light source of the projector to the optical center of the camera,
Figure DEST_PATH_IMAGE045A
is the projected fringe spacing;

S3、利用PCL(Point Cloud Learning)对重建的点云数据集中的三维模型进行法向量估计，并计算出被测物表面法向量相对CCD相机光轴的夹角

Figure DEST_PATH_IMAGE002AA
；S3. Use PCL (Point Cloud Learning) to estimate the normal vector of the 3D model in the reconstructed point cloud dataset, and calculate the angle between the surface normal vector of the measured object and the optical axis of the CCD camera
Figure DEST_PATH_IMAGE002AA
;

其中，法向量估计方法为：对点云数据集进行法向量估计，基于局部平面拟合，创建任一点临近元素的协方差矩阵，求其最小特征值对应的特征向量即为该局部平面法向量

Figure DEST_PATH_IMAGE047AA
；对于每一个点
Figure DEST_PATH_IMAGE049AA
，其对应的协方差矩阵
Figure DEST_PATH_IMAGE051A
为:Among them, the normal vector estimation method is: to estimate the normal vector of the point cloud data set, based on the local plane fitting, create the covariance matrix of the adjacent elements at any point, and find the eigenvector corresponding to the minimum eigenvalue, which is the local plane normal vector
Figure DEST_PATH_IMAGE047AA
; for each point
Figure DEST_PATH_IMAGE049AA
, and its corresponding covariance matrix
Figure DEST_PATH_IMAGE051A
for:

Figure DEST_PATH_IMAGE053A
；
Figure DEST_PATH_IMAGE053A
;

Figure DEST_PATH_IMAGE055A
；
Figure DEST_PATH_IMAGE055A
;

式中，

Figure DEST_PATH_IMAGE057A
是点
Figure DEST_PATH_IMAGE049AAA
邻近点的数目，
Figure DEST_PATH_IMAGE137
表示最邻近元素的三维质心，
Figure DEST_PATH_IMAGE062A
分别表示为协方差矩阵的第
Figure DEST_PATH_IMAGE064A
个特征值和特征向量，当法向方向朝相机方向时，满足
Figure DEST_PATH_IMAGE066A
,
Figure DEST_PATH_IMAGE142
为点云数据集的视点；In the formula,
Figure DEST_PATH_IMAGE057A
is the point
Figure DEST_PATH_IMAGE049AAA
the number of neighboring points,
Figure DEST_PATH_IMAGE137
represents the 3D centroid of the nearest neighbor element,
Figure DEST_PATH_IMAGE062A
Respectively expressed as the first covariance matrix
Figure DEST_PATH_IMAGE064A
eigenvalues and eigenvectors, when the normal direction is towards the camera direction, satisfy
Figure DEST_PATH_IMAGE066A
,
Figure DEST_PATH_IMAGE142
is the viewpoint of the point cloud dataset;

计算被测物表面法向量相对CCD相机光轴的夹角

Figure DEST_PATH_IMAGE002AAA
为：Calculate the angle between the surface normal vector of the measured object and the optical axis of the CCD camera
Figure DEST_PATH_IMAGE002AAA
for:

Figure DEST_PATH_IMAGE071A
；
Figure DEST_PATH_IMAGE071A
;

式中，

Figure DEST_PATH_IMAGE047AAA
为被测物表面法向量，
Figure DEST_PATH_IMAGE074A
为CCD相机光轴方向的单位向量；In the formula,
Figure DEST_PATH_IMAGE047AAA
is the surface normal vector of the measured object,
Figure DEST_PATH_IMAGE074A
is the unit vector in the direction of the optical axis of the CCD camera;

S4、激光发生器1投射激光到被测物表面3，通过对被测物施加外部载荷，由CCD相机分别采集被测物表面变形前后的散斑包裹相位图并进行灰度处理和滤波处理；S4. The laser generator 1 projects laser light onto the surface of the measured object 3. By applying an external load to the measured object, the CCD camera collects the speckle wrapping phase images before and after the surface deformation of the measured object, and performs grayscale processing and filtering processing;

S5、计算机模块5利用相移法对CCD相机采集的散斑包裹相位图提取相位，并利用最小二乘解包裹算法对散斑包裹相位图进行相位展开，获得解包后相位分布信息，代入波长、剪切量等参数计算得到所测得的表面离面位移信息（即光程差

Figure DEST_PATH_IMAGE004AAA
）；S5. The computer module 5 uses the phase shift method to extract the phase from the speckle-wrapped phase map collected by the CCD camera, and uses the least squares unwrapping algorithm to perform phase unwrapping on the speckle-wrapped phase map to obtain the unwrapped phase distribution information and substitute it into the wavelength , shear amount and other parameters are calculated to obtain the measured surface out-of-plane displacement information (that is, the optical path difference
Figure DEST_PATH_IMAGE004AAA
);

其中，通过对散斑包裹相位图进行解包裹计算，Among them, by unwrapping the speckle wrapped phase map,

对散斑包裹相位图进行解包裹计算的过程为：The process of unwrapping the speckle wrapping phase map is as follows:

变形前的散斑图的光强表达式为

Figure DEST_PATH_IMAGE149
，The light intensity expression of the speckle pattern before deformation is
Figure DEST_PATH_IMAGE149
,

Figure DEST_PATH_IMAGE151
；
Figure DEST_PATH_IMAGE151
;

变形后的光强表达式

Figure DEST_PATH_IMAGE101A
为：Transformed light intensity expression
Figure DEST_PATH_IMAGE101A
for:

Figure DEST_PATH_IMAGE103A
；
Figure DEST_PATH_IMAGE103A
;

将变形前后的条纹图进行相减得到四幅相位包裹图

Figure DEST_PATH_IMAGE105A
，Subtract the fringe images before and after deformation to obtain four phase wrapping images
Figure DEST_PATH_IMAGE105A
,

Figure DEST_PATH_IMAGE156
；
Figure DEST_PATH_IMAGE156
;

根据四部相移原理，得到变形前后相位变化量：According to the four-part phase shift principle, the phase change before and after deformation is obtained:

Figure DEST_PATH_IMAGE158
；
Figure DEST_PATH_IMAGE158
;

需要对其进行解包裹处理得到展开相位图，得到相位分布信息

Figure DEST_PATH_IMAGE076AA
和离面位移导数
Figure DEST_PATH_IMAGE112A
（
Figure DEST_PATH_IMAGE080AAA
方向剪切）之间的关系为：It needs to be unwrapped to get the unfolded phase map and get the phase distribution information
Figure DEST_PATH_IMAGE076AA
and out-of-plane displacement derivatives
Figure DEST_PATH_IMAGE112A
(
Figure DEST_PATH_IMAGE080AAA
The relationship between shear direction) is:

Figure DEST_PATH_IMAGE082AA
Figure DEST_PATH_IMAGE082AA

对其积分求解离面位移即光程差

Figure DEST_PATH_IMAGE084AA
；Solve the out-of-plane displacement, that is, the optical path difference by its integral
Figure DEST_PATH_IMAGE084AA
;

式中，

Figure DEST_PATH_IMAGE086A
为沿
Figure DEST_PATH_IMAGE080AAAA
方向的剪切量，
Figure DEST_PATH_IMAGE089A
为CCD相机与光源的夹角，
Figure DEST_PATH_IMAGE091A
为激光波长；In the formula,
Figure DEST_PATH_IMAGE086A
for along
Figure DEST_PATH_IMAGE080AAAA
The amount of shear in the direction,
Figure DEST_PATH_IMAGE089A
is the angle between the CCD camera and the light source,
Figure DEST_PATH_IMAGE091A
is the laser wavelength;

S6、建立激光散斑所测的离面位移测量值（即光程差

Figure DEST_PATH_IMAGE169
）与被测物体表面实际变形的离面位移
Figure DEST_PATH_IMAGE007AA
之间的几何关系；S6. Establish the measured value of the out-of-plane displacement measured by the laser speckle (that is, the optical path difference
Figure DEST_PATH_IMAGE169
) and the out-of-plane displacement of the actual deformation of the surface of the measured object
Figure DEST_PATH_IMAGE007AA
the geometric relationship between

其中，激光剪切散斑法测量离面位移信息是将变化前后的相位信息进行相减，得到光轴方向的离面位移信息（即光程差），而物体发生微小离面形变时其方向是沿表面法向量方向，故所测得光程差

Figure DEST_PATH_IMAGE169A
与实际变形量
Figure DEST_PATH_IMAGE007AAA
之间的关系为：Among them, the laser shearing speckle method measures the out-of-plane displacement information by subtracting the phase information before and after the change to obtain the out-of-plane displacement information in the direction of the optical axis (that is, the optical path difference). When the object undergoes a small out-of-plane deformation, its direction is along the surface normal vector direction, so the measured optical path difference
Figure DEST_PATH_IMAGE169A
and actual deformation
Figure DEST_PATH_IMAGE007AAA
The relationship between is:

Figure DEST_PATH_IMAGE095A
；
Figure DEST_PATH_IMAGE095A
;

S7、根据S6中的几何关系，利用被测物体表面法向量相对CCD相机光轴的夹角

Figure DEST_PATH_IMAGE009A
对散斑剪切干涉所测得的离面位移信息进行修正，得到修正离面位移
Figure DEST_PATH_IMAGE176
S7. According to the geometric relationship in S6, use the angle between the surface normal vector of the measured object and the optical axis of the CCD camera
Figure DEST_PATH_IMAGE009A
Correct the out-of-plane displacement information measured by speckle shear interference to obtain the corrected out-of-plane displacement
Figure DEST_PATH_IMAGE176

在步骤S1和S4，中均由同一CCD相机（或光轴平行的两组CCD相机）分别获取被调制的正弦条纹图和散斑包裹相位图，投影仪投出正弦条纹到被测物体表面，光路经由透镜、剪切干涉系统被CCD相机采集，此时剪切干涉系统未处于干涉状态，计算机模块处理得到被测物的三维信息，激光发生器发出的激光阵列经扩束装置后照射在被测物表面，光路由剪切干涉系统分为两束光在空间上形成干涉，由CCD相机采集到散斑包裹相位图。In steps S1 and S4, the same CCD camera (or two sets of CCD cameras whose optical axes are parallel) obtains the modulated sinusoidal fringe pattern and the speckle wrapping phase pattern respectively, and the projector projects the sinusoidal fringe pattern onto the surface of the measured object. The optical path is collected by the CCD camera through the lens and the shearing interference system. At this time, the shearing interference system is not in the interference state. The computer module processes and obtains the three-dimensional information of the measured object. On the surface of the object to be measured, the light is divided into two beams by the shearing interference system to form interference in space, and the speckle wrapping phase map is collected by the CCD camera.

虽然本发明所揭露的实施方式如上，但所述的内容只是为了便于理解本发明而采用的实施方式，并非用以限定本发明。任何本发明所属技术领域内的技术人员，在不脱离本发明所揭露的精神和范围的前提下，可以在实施的形式及细节上作任何的修改与变化，但本发明的专利保护范围，仍须以所附的权利要求书所界定的范围为准。Although the embodiments disclosed in the present invention are as above, the described content is only an embodiment adopted for the convenience of understanding the present invention, and is not intended to limit the present invention. Anyone skilled in the technical field to which the present invention belongs can make any modifications and changes in the form and details of the implementation without departing from the spirit and scope disclosed in the present invention, but the patent protection scope of the present invention remains the same. The scope defined by the appended claims shall prevail.

Claims (8)

1.一种基于散斑剪切干涉的计量曲面物体离面位移方法，其特征在于，包括如下步骤：1. A method for measuring the out-of-plane displacement of a curved surface object based on speckle shear interference, characterized in that it comprises the following steps: S1、投影仪投出正弦条纹到被测物表面，由CCD相机采集受被测物调制后的正弦条纹图并进行灰度处理；S1. The projector casts sinusoidal fringes to the surface of the measured object, and the CCD camera collects the sinusoidal fringe pattern modulated by the measured object and performs grayscale processing; S2、利用相移法对CCD相机采集的受调制的投影条纹图像提取包裹相位，结合多频外插法进行解包裹计算，得到绝对相位信息,获取物体相对相机的三维坐标；S2. Using the phase shift method to extract the wrapped phase from the modulated projected fringe image collected by the CCD camera, and combine the multi-frequency extrapolation method to perform unwrapped calculations to obtain absolute phase information and obtain the three-dimensional coordinates of the object relative to the camera; S3、利用PCL(Point Cloud Learning)对重建的点云数据集中的三维模型进行法向量估计，并计算出被测物表面法向量相对CCD相机光轴的夹角
Figure 28988DEST_PATH_IMAGE002
；S3. Use PCL (Point Cloud Learning) to estimate the normal vector of the 3D model in the reconstructed point cloud dataset, and calculate the angle between the surface normal vector of the measured object and the optical axis of the CCD camera
Figure 28988DEST_PATH_IMAGE002
; S4、激光器投射激光到被测物表面，通过对被测物施加外部载荷，由CCD相机分别采集被测物表面变形前后的散斑包裹相位图并进行灰度处理和滤波处理；S4. The laser projects laser light onto the surface of the measured object, and by applying an external load to the measured object, the CCD camera collects the speckle wrapping phase images before and after the surface deformation of the measured object, and performs grayscale processing and filtering processing; S5、利用相移法对CCD相机采集的散斑包裹相位图提取相位，并利用最小二乘解包裹算法对散斑包裹相位图进行相位展开，获得解包后相位分布信息，代入波长、剪切量等参数计算得到所测得的表面离面位移信息（即光程差
Figure 398658DEST_PATH_IMAGE004
）；S5. Use the phase shift method to extract the phase from the speckle-wrapped phase map collected by the CCD camera, and use the least squares unwrapping algorithm to perform phase unwrapping on the speckle-wrapped phase map to obtain the unwrapped phase distribution information, which is substituted into the wavelength, shear Calculate the measured surface out-of-plane displacement information (that is, the optical path difference
Figure 398658DEST_PATH_IMAGE004
); S6、建立激光散斑所测的离面位移测量值（即光程差
Figure DEST_PATH_IMAGE005
）与被测物体表面实际变形的离面位移
Figure 538915DEST_PATH_IMAGE007
之间的几何关系；S6. Establish the measured value of the out-of-plane displacement measured by the laser speckle (that is, the optical path difference
Figure DEST_PATH_IMAGE005
) and the out-of-plane displacement of the actual deformation of the surface of the measured object
Figure 538915DEST_PATH_IMAGE007
the geometric relationship between S7、根据S6中的几何关系，利用被测物体表面法向量相对CCD相机光轴的夹角
Figure 871807DEST_PATH_IMAGE009
对散斑剪切干涉所测得的离面位移进行修正，求得实际的离面位移
Figure 873130DEST_PATH_IMAGE011
。S7. According to the geometric relationship in S6, use the angle between the surface normal vector of the measured object and the optical axis of the CCD camera
Figure 871807DEST_PATH_IMAGE009
Correct the out-of-plane displacement measured by speckle shear interference to obtain the actual out-of-plane displacement
Figure 873130DEST_PATH_IMAGE011
. 2.根据权力要求1所述的一种基于散斑剪切干涉的计量曲面物体离面位移方法，其特征在于，所述步骤S2中，求解绝对相位信息的过程如下：2. A method for measuring the out-of-plane displacement of a curved surface object based on speckle shearing interference according to claim 1, characterized in that, in the step S2, the process of solving the absolute phase information is as follows: 相机采集的相位条纹图的数学表达式为：The mathematical expression of the phase fringe pattern collected by the camera is:
Figure 898855DEST_PATH_IMAGE013
Figure 898855DEST_PATH_IMAGE013
 式中，
Figure 851374DEST_PATH_IMAGE015
为条纹光强，
Figure 987957DEST_PATH_IMAGE017
为图像像素坐标，
Figure 109366DEST_PATH_IMAGE019
为背景光强分布，
Figure 40413DEST_PATH_IMAGE021
为光强调制度，
Figure 483158DEST_PATH_IMAGE023
为待求相位，
Figure 423432DEST_PATH_IMAGE025
为相移量，其中
Figure 884500DEST_PATH_IMAGE027
；In the formula,
Figure 851374DEST_PATH_IMAGE015
is the fringe intensity,
Figure 987957DEST_PATH_IMAGE017
is the image pixel coordinates,
Figure 109366DEST_PATH_IMAGE019
is the background light intensity distribution,
Figure 40413DEST_PATH_IMAGE021
For light accentuation system,
Figure 483158DEST_PATH_IMAGE023
For the desired phase,
Figure 423432DEST_PATH_IMAGE025
is the amount of phase shift, where
Figure 884500DEST_PATH_IMAGE027
; 使用相移法求取相位
Figure 766875DEST_PATH_IMAGE029
，解得：Find the phase using the phase shift method
Figure 766875DEST_PATH_IMAGE029
,Solutions have to:
Figure 211762DEST_PATH_IMAGE031
；
Figure 211762DEST_PATH_IMAGE031
; 利用多频外插方法对其相位展开得到绝对相位
Figure 166512DEST_PATH_IMAGE033
，相位分布与高度关系为：Using the multi-frequency extrapolation method to expand its phase to obtain the absolute phase
Figure 166512DEST_PATH_IMAGE033
, the relationship between phase distribution and height is:
Figure 13246DEST_PATH_IMAGE035
；
Figure 13246DEST_PATH_IMAGE035
; 式中：
Figure 551674DEST_PATH_IMAGE037
为物体的高度信息分布，
Figure 733126DEST_PATH_IMAGE039
为被测物的相位变化量，
Figure 749624DEST_PATH_IMAGE041
为相机光心到参考平面的距离，
Figure 201596DEST_PATH_IMAGE043
为投影仪光源到相机光心的距离，
Figure 176505DEST_PATH_IMAGE045
为投影条纹间距。In the formula:
Figure 551674DEST_PATH_IMAGE037
is the height information distribution of the object,
Figure 733126DEST_PATH_IMAGE039
is the phase change of the measured object,
Figure 749624DEST_PATH_IMAGE041
is the distance from the optical center of the camera to the reference plane,
Figure 201596DEST_PATH_IMAGE043
is the distance from the light source of the projector to the optical center of the camera,
Figure 176505DEST_PATH_IMAGE045
is the projected fringe spacing. 3.根据权力要求1所述的一种基于散斑剪切干涉的计量曲面物体离面位移方法，其特征在于，所述步骤S3中，对点云数据集进行法向量估计，基于局部平面拟合，创建任一点临近元素的协方差矩阵，求其最小特征值对应的特征向量即为该局部平面法向量
Figure 330406DEST_PATH_IMAGE047
；对于每一个点
Figure 399862DEST_PATH_IMAGE049
，其对应的协方差矩阵
Figure 955608DEST_PATH_IMAGE051
为:3. A method for measuring the out-of-plane displacement of a curved surface object based on speckle shearing interference according to claim 1, characterized in that, in the step S3, the normal vector estimation is performed on the point cloud data set, based on the local plane approximation Create a covariance matrix of adjacent elements at any point, and find the eigenvector corresponding to its minimum eigenvalue to be the local plane normal vector
Figure 330406DEST_PATH_IMAGE047
; for each point
Figure 399862DEST_PATH_IMAGE049
, and its corresponding covariance matrix
Figure 955608DEST_PATH_IMAGE051
for:
Figure 583642DEST_PATH_IMAGE053
；
Figure 583642DEST_PATH_IMAGE053
;
Figure 959260DEST_PATH_IMAGE055
；
Figure 959260DEST_PATH_IMAGE055
; 式中，
Figure 566828DEST_PATH_IMAGE057
是点
Figure DEST_PATH_IMAGE058
邻近点的数目，
Figure 931075DEST_PATH_IMAGE060
表示最邻近元素的三维质心，
Figure 451049DEST_PATH_IMAGE062
分别表示为协方差矩阵的第
Figure 828810DEST_PATH_IMAGE064
个特征值和特征向量，当法向方向朝相机方向时，满足
Figure 990801DEST_PATH_IMAGE066
,
Figure 9222DEST_PATH_IMAGE068
为点云数据集的视点。In the formula,
Figure 566828DEST_PATH_IMAGE057
is the point
Figure DEST_PATH_IMAGE058
the number of neighboring points,
Figure 931075DEST_PATH_IMAGE060
represents the 3D centroid of the nearest neighbor element,
Figure 451049DEST_PATH_IMAGE062
Respectively expressed as the first covariance matrix
Figure 828810DEST_PATH_IMAGE064
eigenvalues and eigenvectors, when the normal direction is towards the camera direction, satisfy
Figure 990801DEST_PATH_IMAGE066
,
Figure 9222DEST_PATH_IMAGE068
is the viewpoint of the point cloud dataset. 4.根据权力要求1所述的一种基于散斑剪切干涉的计量曲面物体离面位移方法，其特征在于，所述步骤S3中，计算被测物表面法向量相对CCD相机光轴的夹角
Figure 496835DEST_PATH_IMAGE002
：4. A method for measuring the out-of-plane displacement of a curved surface object based on speckle shear interference according to claim 1, characterized in that, in the step S3, the distance between the surface normal vector of the measured object and the optical axis of the CCD camera is calculated. horn
Figure 496835DEST_PATH_IMAGE002
:
Figure DEST_PATH_IMAGE070
；
Figure DEST_PATH_IMAGE070
; 式中，
Figure 830734DEST_PATH_IMAGE071
为被测物表面法向量，
Figure DEST_PATH_IMAGE073
为CCD相机光轴方向的单位向量。In the formula,
Figure 830734DEST_PATH_IMAGE071
is the surface normal vector of the measured object,
Figure DEST_PATH_IMAGE073
is the unit vector in the direction of the optical axis of the CCD camera. 5.根据权利要求1所述的一种基于散斑剪切干涉的计量曲面物体离面位移方法，其特征在于，所述步骤S5中，通过对散斑包裹相位图进行解包裹计算，得到相位分布信息
Figure DEST_PATH_IMAGE075
和离面位移导数
Figure DEST_PATH_IMAGE077
（
Figure DEST_PATH_IMAGE079
方向剪切）之间的关系：5. A method for measuring the out-of-plane displacement of a curved surface object based on speckle shear interference according to claim 1, characterized in that in the step S5, the phase is obtained by unwrapping and calculating the speckle-wrapped phase map distribution information
Figure DEST_PATH_IMAGE075
and out-of-plane displacement derivatives
Figure DEST_PATH_IMAGE077
(
Figure DEST_PATH_IMAGE079
Direction shear) relationship between:
Figure DEST_PATH_IMAGE081
Figure DEST_PATH_IMAGE081
 对其积分求解离面位移即光程差
Figure DEST_PATH_IMAGE083
；Solve the out-of-plane displacement, that is, the optical path difference by its integral
Figure DEST_PATH_IMAGE083
; 式中，
Figure DEST_PATH_IMAGE085
为沿
Figure 701475DEST_PATH_IMAGE079
方向的剪切量，
Figure DEST_PATH_IMAGE087
为CCD相机与光源的夹角，
Figure 804429DEST_PATH_IMAGE089
为激光波长。In the formula,
Figure DEST_PATH_IMAGE085
for along
Figure 701475DEST_PATH_IMAGE079
The amount of shear in the direction,
Figure DEST_PATH_IMAGE087
is the angle between the CCD camera and the light source,
Figure 804429DEST_PATH_IMAGE089
is the laser wavelength. 6.根据权利要求1所述一种基于散斑剪切干涉的计量曲面物体离面位移方法，其特征在于，所述步骤S6中，激光剪切散斑法测量离面位移信息是将变化前后的相位信息进行相减，得到光轴方向的离面位移信息（即光程差），而物体发生微小离面形变时其方向是沿表面法向量方向，故所测得光程差
Figure 197365DEST_PATH_IMAGE005
与实际变形量
Figure 566029DEST_PATH_IMAGE007
之间的关系为：6. A method for measuring the out-of-plane displacement of a curved surface object based on speckle shearing interference according to claim 1, characterized in that, in the step S6, the laser shearing speckle method measures the out-of-plane displacement information before and after the change Subtract the phase information of the object to obtain the out-of-plane displacement information in the direction of the optical axis (that is, the optical path difference). When the object undergoes a small out-of-plane deformation, its direction is along the direction of the surface normal vector, so the measured optical path difference
Figure 197365DEST_PATH_IMAGE005
and actual deformation
Figure 566029DEST_PATH_IMAGE007
The relationship between is:
Figure 600981DEST_PATH_IMAGE091
。
Figure 600981DEST_PATH_IMAGE091
. 7.根据权利要求5所述的一种基于散斑剪切干涉的计量曲面物体离面位移方法，其特征在于，所述步骤S5中，对散斑包裹相位图进行解包裹计算的过程为：7. A method for measuring out-of-plane displacement of curved surface objects based on speckle shear interference according to claim 5, characterized in that, in the step S5, the process of unwrapping and calculating the speckle wrapping phase map is: 变形前的散斑图的光强表达式为
Figure DEST_PATH_IMAGE093
，The light intensity expression of the speckle pattern before deformation is
Figure DEST_PATH_IMAGE093
,
Figure 325486DEST_PATH_IMAGE095
；
Figure 325486DEST_PATH_IMAGE095
; 变形后的光强表达式
Figure 873011DEST_PATH_IMAGE097
为：Transformed light intensity expression
Figure 873011DEST_PATH_IMAGE097
for:
Figure 463392DEST_PATH_IMAGE099
；
Figure 463392DEST_PATH_IMAGE099
; 将变形前后的条纹图进行相减得到四幅相位包裹图
Figure 302035DEST_PATH_IMAGE101
，Subtract the fringe images before and after deformation to obtain four phase wrapping images
Figure 302035DEST_PATH_IMAGE101
,
Figure 442615DEST_PATH_IMAGE103
；
Figure 442615DEST_PATH_IMAGE103
; 根据四部相移原理，得到变形前后相位变化量：According to the four-part phase shift principle, the phase change before and after deformation is obtained:
Figure 177353DEST_PATH_IMAGE105
；
Figure 177353DEST_PATH_IMAGE105
; 需要对其进行解包裹处理得到展开相位图，得到相位分布信息
Figure 238719DEST_PATH_IMAGE075
和离面位移导数
Figure 881053DEST_PATH_IMAGE077
（
Figure 94997DEST_PATH_IMAGE079
方向剪切）之间的关系为：It needs to be unwrapped to get the unfolded phase map and get the phase distribution information
Figure 238719DEST_PATH_IMAGE075
and out-of-plane displacement derivatives
Figure 881053DEST_PATH_IMAGE077
(
Figure 94997DEST_PATH_IMAGE079
The relationship between shear direction) is:
Figure 16947DEST_PATH_IMAGE081
Figure 16947DEST_PATH_IMAGE081
 对其积分求解离面位移即光程差
Figure 581921DEST_PATH_IMAGE083
。Solve the out-of-plane displacement, that is, the optical path difference by its integral
Figure 581921DEST_PATH_IMAGE083
. 8.根据权利要求1所述一种基于散斑剪切干涉的计量曲面物体离面位移方法，其特征在于，所述步骤S1和S4，中均由同一CCD相机（或光轴平行的两组CCD相机）分别获取被调制的正弦条纹图和散斑包裹相位图，投影仪投出正弦条纹到被测物体表面，光路经由透镜、剪切干涉系统被CCD相机采集，此时剪切干涉系统未处于干涉状态，计算机模块处理得到被测物的三维信息，激光发生器发出的激光阵列经扩束装置后照射在被测物表面，光路由剪切干涉系统分为两束光在空间上形成干涉，由CCD相机采集到散斑包裹相位图。8. A method for measuring the out-of-plane displacement of curved surface objects based on speckle shearing interference according to claim 1, characterized in that, in the steps S1 and S4, the same CCD camera (or two groups with parallel optical axes) CCD camera) obtains the modulated sinusoidal fringe pattern and the speckle wrapping phase pattern respectively, the projector projects the sinusoidal fringe to the surface of the measured object, and the optical path is collected by the CCD camera through the lens and the shearing interference system. At this time, the shearing interference system is not In the interference state, the computer module processes the three-dimensional information of the measured object. The laser array emitted by the laser generator is irradiated on the surface of the measured object after passing through the beam expander. The optical path is divided into two beams by the shear interference system to form interference in space. , the speckle-wrapped phase map collected by the CCD camera.
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Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN116429680A (en) * 2023-03-31 2023-07-14 北京京仪自动化装备技术股份有限公司 Adhesion measurement system, method and electronic device
CN120160551A (en) * 2025-02-20 2025-06-17 华中科技大学 A method and system for detecting warpage of electronic packaging based on background schlieren
CN120871411A (en) * 2025-09-22 2025-10-31 苏州大学 Interference fringe generating element, generating device and defect detecting method
CN121409130A (en) * 2025-12-26 2026-01-27 深圳北理莫斯科大学 Deformation measurement methods, devices and electronic equipment
CN121409130B (en) * 2025-12-26 2026-04-03 深圳北理莫斯科大学 Deformation measurement method and device and electronic equipment

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2003139515A (en) * 2001-11-02 2003-05-14 Fukuoka Prefecture Method for measuring absolute value of deformation quantity using speckle
CN1916563A (en) * 2005-08-19 2007-02-21 韩国轮胎株式会社 Tyre touchdown shape measuring device using laser disperse spot shearing interference method
CN106226313A (en) * 2016-07-01 2016-12-14 华南理工大学 A kind of depth of defect detection method interfered based on speckle-shearing
CN108106556A (en) * 2018-02-02 2018-06-01 上海交通大学 Based on the curved face object of digital speckle interference from face distortion measurement method and device
CN114527129A (en) * 2021-12-10 2022-05-24 桂林电子科技大学 Small workpiece internal defect detection device and method based on shearing speckle interference

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2003139515A (en) * 2001-11-02 2003-05-14 Fukuoka Prefecture Method for measuring absolute value of deformation quantity using speckle
CN1916563A (en) * 2005-08-19 2007-02-21 韩国轮胎株式会社 Tyre touchdown shape measuring device using laser disperse spot shearing interference method
CN106226313A (en) * 2016-07-01 2016-12-14 华南理工大学 A kind of depth of defect detection method interfered based on speckle-shearing
CN108106556A (en) * 2018-02-02 2018-06-01 上海交通大学 Based on the curved face object of digital speckle interference from face distortion measurement method and device
CN114527129A (en) * 2021-12-10 2022-05-24 桂林电子科技大学 Small workpiece internal defect detection device and method based on shearing speckle interference

Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN116429680A (en) * 2023-03-31 2023-07-14 北京京仪自动化装备技术股份有限公司 Adhesion measurement system, method and electronic device
CN116429680B (en) * 2023-03-31 2026-03-27 北京京仪自动化装备技术股份有限公司 Adhesion force measurement system, method and electronic equipment
CN120160551A (en) * 2025-02-20 2025-06-17 华中科技大学 A method and system for detecting warpage of electronic packaging based on background schlieren
CN120871411A (en) * 2025-09-22 2025-10-31 苏州大学 Interference fringe generating element, generating device and defect detecting method
CN121409130A (en) * 2025-12-26 2026-01-27 深圳北理莫斯科大学 Deformation measurement methods, devices and electronic equipment
CN121409130B (en) * 2025-12-26 2026-04-03 深圳北理莫斯科大学 Deformation measurement method and device and electronic equipment

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