CN108844459B - Calibration method and device of blade digital sample plate detection system - Google Patents
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Abstract
Description
技术领域technical field
本发明涉及视觉测量技术领域，尤其涉及一种叶片数字化样板检测系统的标定方法及叶片数字化样板检测系统的标定装置。The invention relates to the technical field of visual measurement, in particular to a calibration method of a blade digital template detection system and a calibration device of the blade digital template detection system.
背景技术Background technique
燃气轮机被广泛应用于航空、航天、能源等领域，作为燃气轮机中的核心零件，透平叶片具有结构复杂、制造工艺要求高、测量参数多等特点，其形状误差影响整个燃气轮机的能量转换效率，因此对不规则型面测量的精准性、有效性提出要求。不同叶片测量方法的标定方式直接决定了整个测量的精度，反应了测量方法的适用性、经济性、高效性。为适用于一种能够快速扫描叶片型面、获取叶片完整点云、自动分析测量参数、输出检测报告的叶片数字化样板检测装置的叶片测量特点，需为其制定一种准确、便捷、快速、简易的系统标定方法。Gas turbines are widely used in aviation, aerospace, energy and other fields. As the core parts of gas turbines, turbine blades have the characteristics of complex structure, high manufacturing process requirements, and many measurement parameters. The shape error affects the energy conversion efficiency of the entire gas turbine. Therefore, Requirements for the accuracy and effectiveness of irregular profile measurement. The calibration methods of different blade measurement methods directly determine the accuracy of the entire measurement, reflecting the applicability, economy and efficiency of the measurement methods. In order to be suitable for the blade measurement characteristics of a blade digital template detection device that can quickly scan the blade profile, obtain the complete point cloud of the blade, automatically analyze the measurement parameters, and output the detection report, it is necessary to formulate an accurate, convenient, fast and simple for it. system calibration method.
非接触式测量方法主要使用光学视觉检测的方法。利用激光三角测量原理需要对激光平面进行标定。陶立等用由2个完全垂直的平面组成的立体标靶同时标定测量系统的摄像机参数和光平面参数，但需要制作特殊标定标靶。另外双目视觉系统拍摄激光图片，用立体视觉的方法对双相机图像进行立体矫正，获取激光条纹中心，匹配条纹中心与相机的对应性，也可标定出激光平面参数，但需要两个相机不适用于叶片数字化样板检测装置中。单目激光视觉传感器与运动机构的安装必然存在误差，测量坐标系与实际运动方向之间的关系需要进行标定。利用制作特殊形状的标定物，通过扫描重建特殊标定物，提取特征点在三维空间中的信息来获取视觉传感器运动方向信息，其标定过程较为繁琐，且标定物的制作精度高、成本高。对于带有转台的叶片检测机构中，转台的回转中心标定结果影响叶片型面测量点的坐标转换结果。转台回转中心标定方法有三点法。测量设备要求为光学测头与接触式测头的复合式测头。三点法把标定球置于转台某一位置，保证测头z轴固定，在xy平面内测量标准球上三点，三点呈等腰三角形排布，利用三点求出此位置球的截面圆心坐标，然后旋转转台，并保持标准球与转台不发生相对相对运动，依次共求取三个位置的截面圆心来求解转台回转中心。该方法需要知道标准球上三个点在xy平面的坐标，只旋转了2次求取标准球3个位置的截面圆心，标定精度不高。Non-contact measurement methods mainly use optical visual inspection methods. Using the principle of laser triangulation requires calibration of the laser plane. Tao Li et al. used a stereo target composed of two completely vertical planes to calibrate the camera parameters and light plane parameters of the measurement system at the same time, but they needed to make a special calibration target. In addition, the binocular vision system captures laser pictures, uses stereo vision to perform stereo correction on the images of the dual cameras, obtains the laser fringe center, matches the correspondence between the fringe center and the camera, and can also calibrate the laser plane parameters, but the two cameras are not required. It is suitable for blade digital template detection device. There must be errors in the installation of the monocular laser vision sensor and the motion mechanism, and the relationship between the measurement coordinate system and the actual motion direction needs to be calibrated. Using a calibration object with a special shape, reconstructing the special calibration object by scanning, and extracting the information of the feature points in the three-dimensional space to obtain the motion direction information of the vision sensor, the calibration process is relatively cumbersome, and the production accuracy of the calibration object is high and the cost is high. For the blade detection mechanism with a turntable, the calibration result of the rotation center of the turntable affects the coordinate conversion result of the blade profile measurement point. There are three-point methods for calibrating the rotation center of the turntable. The measuring equipment is required to be a composite probe of an optical probe and a touch probe. The three-point method places the calibration ball at a certain position on the turntable to ensure that the z-axis of the probe is fixed, and measures three points on the standard ball in the xy plane. Then, rotate the turntable, and keep the standard ball and the turntable from relative relative motion, and obtain the center of the section circle at three positions in turn to solve the rotation center of the turntable. This method needs to know the coordinates of the three points on the standard sphere in the xy plane, and only rotates twice to find the center of the section at the three positions of the standard sphere, and the calibration accuracy is not high.
综上对激光平面、运动方向、回转中心的标定方法，现有的标定方法缺陷有：(1)标定效率低(2)标定精度低(3)标定过程繁杂(4)需要制作特定形状的标定块(5)对于采用非接触叶片测量的装置，没有系统完整的标定方法。To sum up the calibration methods for the laser plane, motion direction, and rotation center, the existing calibration methods have the following defects: (1) low calibration efficiency (2) low calibration accuracy (3) complex calibration process (4) need to make a specific shape of the calibration Block (5) There is no systematically complete calibration method for devices employing non-contact blade measurements.
因此，如何提供一种完整的标定方法成为本领域技术人员亟待解决的技术问题。Therefore, how to provide a complete calibration method has become an urgent technical problem to be solved by those skilled in the art.
发明内容SUMMARY OF THE INVENTION
本发明旨在至少解决现有技术中存在的技术问题之一，提供一种叶片数字化样板检测系统的标定方法及叶片数字化样板检测系统的标定装置，以解决现有技术中的问题。The present invention aims to solve at least one of the technical problems existing in the prior art, and provides a calibration method for a blade digital template detection system and a calibration device for a blade digital template detection system, so as to solve the problems in the prior art.
作为本发明的第一个方面，提供一种叶片数字化样板检测系统的标定方法，其中，所述叶片数字化样板检测系统包括第一视觉传感器和第二视觉传感器，所述第一视觉传感器和所述第二视觉传感器对称相对设置，所述叶片数字化样板检测系统的标定方法包括：As a first aspect of the present invention, a method for calibrating a blade digital template detection system is provided, wherein the blade digital template detection system includes a first vision sensor and a second vision sensor, the first vision sensor and the The second vision sensors are symmetrically arranged relative to each other, and the calibration method of the blade digital template detection system includes:
对所述第一视觉传感器和所述第二视觉传感器分别进行摄像机标定得到相机坐标系下的相机参数；Perform camera calibration on the first visual sensor and the second visual sensor respectively to obtain camera parameters in the camera coordinate system;
对所述第一视觉传感器和所述第二视觉传感器分别进行激光光刀平面标定得到测量坐标系下的测量参数；Carrying out laser light knife plane calibration on the first visual sensor and the second visual sensor respectively to obtain the measurement parameters in the measurement coordinate system;
根据所述相机参数以及所述测量参数对所述第一视觉传感器和所述第二视觉传感器分别进行运动方向标定，分别得到所述第一视觉传感器和所述第二视觉传感器的测量坐标系的Y轴与实际运动方向的偏移量；According to the camera parameters and the measurement parameters, the movement directions of the first vision sensor and the second vision sensor are respectively calibrated, and the measurement coordinate systems of the first vision sensor and the second vision sensor are obtained respectively. The offset between the Y axis and the actual motion direction;
分别将所述第一视觉传感器和所述第二视觉传感器的所述相机参数由所述相机坐标系转换到所述测量坐标系，成为所述测量坐标系中的测量参数；respectively converting the camera parameters of the first vision sensor and the second vision sensor from the camera coordinate system to the measurement coordinate system to become measurement parameters in the measurement coordinate system;
对所述第一视觉传感器和所述第二视觉传感器进行位置关系标定；performing positional relationship calibration on the first visual sensor and the second visual sensor;
将所述第二视觉传感器的测量坐标系下的测量参数转换到所述第一视觉传感器的测量坐标系下；Converting the measurement parameters under the measurement coordinate system of the second vision sensor to the measurement coordinate system of the first vision sensor;
对叶片数字化样板检测系统进行系统坐标系标定；Calibration of the system coordinate system for the blade digital template detection system;
将所述第一视觉传感器下的测量坐标系转换到叶片数字化样板检测系统的系统坐标系下，得到所述叶片数字化样板检测系统的系统坐标系下的完整参数。Convert the measurement coordinate system under the first visual sensor to the system coordinate system of the blade digital template detection system to obtain complete parameters under the system coordinate system of the blade digital template detection system.
优选地，所述对所述第一视觉传感器和所述第二视觉传感器分别进行激光光刀平面标定得到测量坐标系下的测量参数包括：Preferably, the measurement parameters obtained in the measurement coordinate system obtained by performing laser light knife plane calibration on the first vision sensor and the second vision sensor respectively include:
通过进行摄像机标定后的摄像机分别拍摄多组无激光条纹和有激光条纹的标定板图像；Shoot multiple sets of calibration plate images without laser streaks and with laser streaks through the cameras after camera calibration;
获取标定板在所述相机坐标系下的位姿；Obtain the pose of the calibration board in the camera coordinate system;
对有激光条纹的图像进行光条中心提取；Extract the center of the light stripe for the image with laser stripes;
计算所述光条中心的物理坐标值；Calculate the physical coordinate value of the center of the light bar;
通过拟合得到所述光条中心的物理坐标值所在的激光光刀平面，得到测量坐标系；Obtain the laser light knife plane where the physical coordinate value of the center of the light bar is located by fitting, and obtain the measurement coordinate system;
输出所述测量坐标系以及所述测量坐标系与所述相机坐标系的变换关系。Output the measurement coordinate system and the transformation relationship between the measurement coordinate system and the camera coordinate system.
优选地，所述获取标定板在所述相机坐标系下的位姿包括：Preferably, the acquiring the pose of the calibration board in the camera coordinate system includes:
根据n个控制点的空间位置信息以该n个控制点的像点信息计算n各控制点在相机坐标系下的位置位姿。According to the spatial position information of the n control points, the position and orientation of each of the n control points in the camera coordinate system is calculated with the image point information of the n control points.
优选地，所述通过拟合得到所述光条中心的物理坐标值所在的激光光刀平面包括：Preferably, the laser light knife plane where the physical coordinate value of the center of the light bar is obtained by fitting includes:
通过最小二乘优化方法拟合所述光条中心的物理坐标值所在的激光光刀平面。The laser light knife plane where the physical coordinate value of the center of the light bar is located is fitted by a least squares optimization method.
优选地，所述根据所述相机参数以及所述测量参数对所述第一视觉传感器和所述第二视觉传感器分别进行运动方向标定，分别得到所述第一视觉传感器和所述第二视觉传感器的测量坐标系的Y轴与实际运动方向的偏移量包括：Preferably, according to the camera parameters and the measurement parameters, the first vision sensor and the second vision sensor are respectively calibrated for movement directions, and the first vision sensor and the second vision sensor are obtained respectively. The offset between the Y axis of the measurement coordinate system and the actual motion direction includes:
将所述第一视觉传感器和所述第二视觉传感器分别在移动模组上移动多个位置，且在移动的每个位置上进行标定板的拍摄；Moving the first visual sensor and the second visual sensor to multiple positions on the mobile module, and photographing the calibration plate at each position of the movement;
获取标定板的位姿；Get the pose of the calibration board;
分别计算所述第一视觉传感器的每个位置的相对姿态变换以及和所述第二视觉传感器的每个位置的相对姿态变换；Calculate the relative attitude transformation of each position of the first vision sensor and the relative attitude transformation of each position of the second vision sensor respectively;
求解运动方向在相机坐标系下的方向向量；Solve the direction vector of the motion direction in the camera coordinate system;
输出所述方向向量。The direction vector is output.
优选地，所述对所述第一视觉传感器和所述第二视觉传感器进行位置关系标定包括：Preferably, the calibrating the positional relationship between the first visual sensor and the second visual sensor includes:
所述第一视觉传感器和所述第二视觉传感器同时扫描测量空间中标定球的若干位置；The first visual sensor and the second visual sensor simultaneously scan several positions of the calibration sphere in the measurement space;
分别三维重建拟合出标定球在不同位置的球心坐标；Respectively reconstruct and fit the sphere center coordinates of the calibration sphere at different positions;
利用刚体变化求出所述第一视觉传感器和所述第二视觉传感器之间的位置关系。The positional relationship between the first vision sensor and the second vision sensor is obtained using the rigid body change.
优选地，对叶片数字化样板检测系统进行系统坐标系标定包括：Preferably, the system coordinate system calibration of the blade digital template detection system includes:
将标定球放置在转台边缘；Place the calibration ball on the edge of the turntable;
通过所述第一视觉传感器扫描重建拟合出所述标定球的球心坐标；The coordinates of the center of the calibration sphere are obtained by scanning and reconstructing the first visual sensor;
保持标定球与转台相对静止，旋转转台，并重复扫描重建拟合的步骤得到所述标定球在多个位置的球心坐标；Keep the calibration ball and the turntable relatively stationary, rotate the turntable, and repeat the steps of scanning, reconstructing and fitting to obtain the spherical center coordinates of the calibration ball at multiple positions;
拟合出转台旋转轴和旋转中心，得到系统坐标系，并得到测量坐标系与系统坐标系的转换关系。The rotation axis and rotation center of the turntable are fitted, and the system coordinate system is obtained, and the conversion relationship between the measurement coordinate system and the system coordinate system is obtained.
优选地，所述第一视觉传感器的相机坐标系包括Pc1(Xc1，Yc1，Zc1)，所述第一视觉传感器的测量坐标系包括Pl1(Xl1，Yl1，Zl1)，所述第二视觉传感器的相机坐标系包括Pc2(Xc2，Yc2，Zc2)，所述第二视觉传感器的测量坐标系包括Pl2(Xl2，Yl2，Zl2)。Preferably, the camera coordinate system of the first vision sensor includes P c1 (X c1 , Y c1 , Z c1 ), and the measurement coordinate system of the first vision sensor includes P l1 (X l1 , Y l1 , Z l1 ) , the camera coordinate system of the second vision sensor includes P c2 (X c2 , Y c2 , Z c2 ), and the measurement coordinate system of the second vision sensor includes P l2 (X l2 , Y l2 , Z l2 ).
优选地，所述叶片数字化样板检测系统的系统坐标系包括Ps(Xs，Ys，Zs)。Preferably, the system coordinate system of the blade digital template detection system includes P s (X s , Y s , Z s ).
作为本发明的第二个方面，提供一种叶片数字化样板检测系统的标定装置，其中，所述叶片数字化样板检测系统的标定装置包括：As a second aspect of the present invention, a calibration device of a blade digital template detection system is provided, wherein the calibration device of the blade digital template detection system includes:
摄像机标定模块，所述摄像机标定模块用于对所述第一视觉传感器和所述第二视觉传感器分别进行摄像机标定得到相机坐标系下的相机参数；a camera calibration module, the camera calibration module is configured to perform camera calibration on the first visual sensor and the second visual sensor respectively to obtain camera parameters in the camera coordinate system;
激光光刀平面标定模块，所述激光光刀平面标定模块用于对所述第一视觉传感器和所述第二视觉传感器分别进行激光光刀平面标定得到测量坐标系下的测量参数；a laser light knife plane calibration module, the laser light knife plane calibration module is used to respectively perform laser light knife plane calibration on the first vision sensor and the second vision sensor to obtain measurement parameters in a measurement coordinate system;
运动方向标定模块，所述运动方向标定模块用于根据所述相机参数以及所述测量参数对所述第一视觉传感器和所述第二视觉传感器分别进行运动方向标定，分别得到所述第一视觉传感器和所述第二视觉传感器的测量坐标系的Y轴与实际运动方向的偏移量；A movement direction calibration module, which is used to calibrate the movement direction of the first vision sensor and the second vision sensor according to the camera parameters and the measurement parameters, respectively, to obtain the first vision sensor. the offset of the Y-axis of the measurement coordinate system of the sensor and the second vision sensor and the actual movement direction;
第一转换模块，所述第一转换模块用于分别将所述第一视觉传感器和所述第二视觉传感器的所述相机参数由所述相机坐标系转换到所述测量坐标系，成为所述测量坐标系中的测量参数；a first conversion module, the first conversion module is configured to respectively convert the camera parameters of the first visual sensor and the second visual sensor from the camera coordinate system to the measurement coordinate system to become the Measurement parameters in the measurement coordinate system;
位置关系标定模块，所述位置关系标定模块用于对所述第一视觉传感器和所述第二视觉传感器进行位置关系标定；a positional relationship calibration module, the positional relationship calibration module is used to perform positional relationship calibration on the first visual sensor and the second visual sensor;
第二转换模块，所述第二转换模块用于将所述第二视觉传感器的测量坐标系下的测量参数转换到所述第一视觉传感器的测量坐标系下；a second conversion module, the second conversion module is configured to convert the measurement parameters in the measurement coordinate system of the second vision sensor to the measurement coordinate system of the first vision sensor;
系统坐标系标定模块，所述系统坐标系标定模块用于对叶片数字化样板检测系统进行系统坐标系标定；a system coordinate system calibration module, the system coordinate system calibration module is used to perform system coordinate system calibration on the blade digital template detection system;
第三转换模块，所述第三转换模块用于将所述第一视觉传感器下的测量坐标系转换到叶片数字化样板检测系统的系统坐标系下，得到所述叶片数字化样板检测系统的系统坐标系下的完整参数。The third conversion module, the third conversion module is used to convert the measurement coordinate system under the first vision sensor to the system coordinate system of the blade digital template detection system to obtain the system coordinate system of the blade digital template detection system full parameters below.
本发明提供的叶片数字化样板检测系统的标定方法，用于对能够快速扫描叶片型面、获取叶片完整点云、自动分析测量参数、输出检测报告的叶片数字化样板检测装置进行系统标定。通过通用标定标靶对所述装置快速完成摄像机标定、激光光刀平面标定、测量运动方向标定、设备位置关系标定、系统坐标系标定，使得准确获取各坐标系之间的相互转化关系，降低标定成本，实现了完整标定，且能够提高整个系统的标定效率，简化系统标定的流程，实现了叶片数字化样板测量装置的适用性。The calibration method of the blade digital template detection system provided by the invention is used for systematic calibration of the blade digital template detection device which can quickly scan the blade profile, obtain the complete point cloud of the blade, automatically analyze the measurement parameters, and output the detection report. Through the universal calibration target, the device can quickly complete camera calibration, laser light knife plane calibration, measurement movement direction calibration, equipment position relationship calibration, and system coordinate system calibration, so that the mutual transformation relationship between each coordinate system can be accurately obtained and the calibration cost can be reduced. , realizes complete calibration, and can improve the calibration efficiency of the whole system, simplify the process of system calibration, and realize the applicability of the blade digital template measurement device.
附图说明Description of drawings
附图是用来提供对本发明的进一步理解，并且构成说明书的一部分，与下面的具体实施方式一起用于解释本发明，但并不构成对本发明的限制。在附图中：The accompanying drawings are used to provide a further understanding of the present invention, and constitute a part of the specification, and together with the following specific embodiments, are used to explain the present invention, but do not constitute a limitation to the present invention. In the attached image:
图1为本发明提供的叶片数字化样板检测系统的标定方法的流程图。FIG. 1 is a flow chart of the calibration method of the blade digital template detection system provided by the present invention.
图2为本发明提供的叶片数字化样板检测系统的各坐标系示意图。FIG. 2 is a schematic diagram of each coordinate system of the blade digital template detection system provided by the present invention.
图3为本发明提供的叶片数字化样板检测系统的标定方法的具体标定流程图。FIG. 3 is a specific calibration flow chart of the calibration method of the blade digital template detection system provided by the present invention.
图4为本发明提供的激光光刀平面标定流程图。FIG. 4 is a flow chart of the laser light knife plane calibration provided by the present invention.
图5为本发明提供的运动方向标定流程图。FIG. 5 is a flow chart of the movement direction calibration provided by the present invention.
图6为本发明提供的两个视觉传感器之间位置关系标定流程图。FIG. 6 is a flow chart of the calibration of the positional relationship between two visual sensors provided by the present invention.
图7为本发明提供的系统坐标系标定流程图。FIG. 7 is a flow chart of the calibration of the system coordinate system provided by the present invention.
图8为本发明提供的叶片数字化样板检测系统的标定装置的结构示意图。FIG. 8 is a schematic structural diagram of the calibration device of the blade digital template detection system provided by the present invention.
具体实施方式Detailed ways
以下结合附图对本发明的具体实施方式进行详细说明。应当理解的是，此处所描述的具体实施方式仅用于说明和解释本发明，并不用于限制本发明。The specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings. It should be understood that the specific embodiments described herein are only used to illustrate and explain the present invention, but not to limit the present invention.
作为本发明的第一个方面，提供一种叶片数字化样板检测系统的标定方法，其中，所述叶片数字化样板检测系统包括第一视觉传感器和第二视觉传感器，所述第一视觉传感器和所述第二视觉传感器对称相对设置，如图1所示，所述叶片数字化样板检测系统的标定方法包括：As a first aspect of the present invention, a method for calibrating a blade digital template detection system is provided, wherein the blade digital template detection system includes a first vision sensor and a second vision sensor, the first vision sensor and the The second vision sensors are symmetrically arranged relative to each other, as shown in FIG. 1 , the calibration method of the blade digital template detection system includes:
S110、对所述第一视觉传感器和所述第二视觉传感器分别进行摄像机标定得到相机坐标系下的相机参数；S110. Perform camera calibration on the first visual sensor and the second visual sensor respectively to obtain camera parameters in a camera coordinate system;
S120、对所述第一视觉传感器和所述第二视觉传感器分别进行激光光刀平面标定得到测量坐标系下的测量参数；S120, performing laser light knife plane calibration on the first visual sensor and the second visual sensor respectively to obtain measurement parameters in a measurement coordinate system;
S130、根据所述相机参数以及所述测量参数对所述第一视觉传感器和所述第二视觉传感器分别进行运动方向标定，分别得到所述第一视觉传感器和所述第二视觉传感器的测量坐标系的Y轴与实际运动方向的偏移量；S130. Perform movement direction calibration on the first vision sensor and the second vision sensor according to the camera parameters and the measurement parameters, respectively, and obtain the measurement coordinates of the first vision sensor and the second vision sensor, respectively. The offset between the Y axis of the system and the actual motion direction;
S140、分别将所述第一视觉传感器和所述第二视觉传感器的所述相机参数由所述相机坐标系转换到所述测量坐标系，成为所述测量坐标系中的测量参数；S140. Convert the camera parameters of the first visual sensor and the second visual sensor respectively from the camera coordinate system to the measurement coordinate system to become the measurement parameters in the measurement coordinate system;
S150、对所述第一视觉传感器和所述第二视觉传感器进行位置关系标定；S150, calibrating the positional relationship between the first visual sensor and the second visual sensor;
S160、将所述第二视觉传感器的测量坐标系下的测量参数转换到所述第一视觉传感器的测量坐标系下；S160, converting the measurement parameters in the measurement coordinate system of the second vision sensor to the measurement coordinate system of the first vision sensor;
S170、对叶片数字化样板检测系统进行系统坐标系标定；S170, calibrating the system coordinate system of the blade digital template detection system;
S180、将所述第一视觉传感器下的测量坐标系转换到叶片数字化样板检测系统的系统坐标系下，得到所述叶片数字化样板检测系统的系统坐标系下的完整参数。S180. Convert the measurement coordinate system under the first visual sensor to the system coordinate system of the blade digital template detection system to obtain complete parameters under the system coordinate system of the blade digital template detection system.
本发明提供的叶片数字化样板检测系统的标定方法，用于对能够快速扫描叶片型面、获取叶片完整点云、自动分析测量参数、输出检测报告的叶片数字化样板检测装置进行系统标定。通过通用标定标靶对所述装置快速完成摄像机标定、激光光刀平面标定、测量运动方向标定、设备位置关系标定、系统坐标系标定，使得准确获取各坐标系之间的相互转化关系，降低标定成本，实现了完整标定，且能够提高整个系统的标定效率，简化系统标定的流程，实现了叶片数字化样板测量装置的适用性。The calibration method of the blade digital template detection system provided by the invention is used for systematic calibration of the blade digital template detection device which can quickly scan the blade profile, obtain the complete point cloud of the blade, automatically analyze the measurement parameters, and output the detection report. Through the universal calibration target, the device can quickly complete camera calibration, laser light knife plane calibration, measurement movement direction calibration, equipment position relationship calibration, and system coordinate system calibration, so that the mutual transformation relationship between each coordinate system can be accurately obtained and the calibration cost can be reduced. , realizes complete calibration, and can improve the calibration efficiency of the whole system, simplify the process of system calibration, and realize the applicability of the blade digital template measurement device.
下面结合图2和图3所示，对本发明提供的叶片数字化样板检测系统的标定方法的工作过程进行详细描述。The working process of the calibration method of the blade digital template detection system provided by the present invention will be described in detail below with reference to FIG. 2 and FIG. 3 .
如图2所示叶片数字化样板检测装置中各坐标系的位置及转换示意图，Pc1(Xc1，Yc1，Zc1)、Pl1(Xl1，Yl1，Zl1)为第一视觉传感器的相机坐标系与测量坐标系，Pc2(Xc2，Yc2，Zc2)、Pl2(Xl2，Yl2，Zl2)为第二视觉传感器的相机坐标系与测量坐标系，Ps(Xs，Ys，Zs)为系统坐标系，[R，T]relative为所述第一视觉传感器和所述第二视觉传感器之间位置关系标定的变换矩阵，[R，T]svstem为设备测量坐标系与系统坐标系的变换矩阵。相机拍摄的激光条纹图片经过光条中心提取，经过运动方向的标定得到的测量坐标系Y轴与实际运动方向的偏移量，将光条中心从相机坐标系下转换到测量坐标系下，通过[R，T]relative将第二视觉传感器测量坐标系下的光条点云变换到第一视觉传感器的测量坐标系下，再由[R，T]svstem将每次转台旋转后测量的点云数据从第一视觉传感器的测量坐标系变换到系统坐标系下。系统标定流程如图3所示，摄像机标定、激光光刀平面标定、测量运动方向标定只需要一个通用视觉标定板，设备位置关系标定、系统坐标系标定只需要一个通用标定球。标定过程涵盖于标定软件中，标定软件集成完整标定过程、标定图片显示、三维点云显示、用户交互操作、点云拟合等功能。标定完成后，不同的视觉传感器在对不同视角被测物扫描重建后，可直接得到统一在系统坐标系下的完整点云。As shown in Figure 2, the position and conversion diagram of each coordinate system in the blade digital template detection device, P c1 (X c1 , Y c1 , Z c1 ), P l1 (X l1 , Y l1 , Z l1 ) are the first visual sensors P c2 (X c2 , Y c2 , Z c2 ), P l2 (X l2 , Y l2 , Z l2 ) are the camera coordinate system and measuring coordinate system of the second vision sensor, P s (X s , Y s , Z s ) is the system coordinate system, [R, T] relative is the transformation matrix for the calibration of the positional relationship between the first vision sensor and the second vision sensor, [R, T] svstem The transformation matrix between the measurement coordinate system and the system coordinate system for the device. The laser stripe image taken by the camera is extracted by the center of the light strip, and the offset of the Y-axis of the measurement coordinate system and the actual movement direction is obtained through the calibration of the movement direction, and the center of the light strip is converted from the camera coordinate system to the measurement coordinate system. [R, T] relative transforms the light bar point cloud under the measurement coordinate system of the second vision sensor to the measurement coordinate system of the first vision sensor, and then [R, T] svstem converts the point cloud measured after each turntable rotation by [R, T] svstem The data is transformed from the measurement coordinate system of the first vision sensor to the system coordinate system. The system calibration process is shown in Figure 3. The camera calibration, the laser light knife plane calibration, and the measurement movement direction calibration only need a general visual calibration board, and the equipment position relationship calibration and system coordinate system calibration only need a general calibration sphere. The calibration process is covered in the calibration software, which integrates the complete calibration process, calibration picture display, 3D point cloud display, user interaction, point cloud fitting and other functions. After the calibration is completed, different vision sensors can directly obtain a complete point cloud unified in the system coordinate system after scanning and reconstructing the measured object from different viewing angles.
具体地，所述对所述第一视觉传感器和所述第二视觉传感器分别进行激光光刀平面标定得到测量坐标系下的测量参数包括：Specifically, the measurement parameters obtained in the measurement coordinate system obtained by performing laser light knife plane calibration on the first vision sensor and the second vision sensor respectively include:
通过进行摄像机标定后的摄像机分别拍摄多组无激光条纹和有激光条纹的标定板图像；Shoot multiple sets of calibration plate images without laser streaks and with laser streaks through the cameras after camera calibration;
获取标定板在所述相机坐标系下的位姿；Obtain the pose of the calibration board in the camera coordinate system;
对有激光条纹的图像进行光条中心提取；Extract the center of the light stripe for the image with laser stripes;
计算所述光条中心的物理坐标值；Calculate the physical coordinate value of the center of the light bar;
通过拟合得到所述光条中心的物理坐标值所在的激光光刀平面，得到测量坐标系；Obtain the laser light knife plane where the physical coordinate value of the center of the light bar is located by fitting, and obtain the measurement coordinate system;
输出所述测量坐标系以及所述测量坐标系与所述相机坐标系的变换关系。Output the measurement coordinate system and the transformation relationship between the measurement coordinate system and the camera coordinate system.
所述获取标定板在所述相机坐标系下的位姿包括：The acquiring the pose of the calibration board in the camera coordinate system includes:
根据n个控制点的空间位置信息以该n个控制点的像点信息计算n各控制点在相机坐标系下的位置位姿。According to the spatial position information of the n control points, the position and orientation of each of the n control points in the camera coordinate system is calculated with the image point information of the n control points.
进一步具体地，所述通过拟合得到所述光条中心的物理坐标值所在的激光光刀平面包括：More specifically, the laser light knife plane where the physical coordinate value of the center of the light bar is obtained by fitting includes:
通过最小二乘优化方法拟合所述光条中心的物理坐标值所在的激光光刀平面。The laser light knife plane where the physical coordinate value of the center of the light bar is located is fitted by a least squares optimization method.
下面结合图4对激光光刀平面标定进行详细说明。The laser light knife plane calibration will be described in detail below with reference to FIG. 4 .
用标定好的摄像机分别在测量空间中拍摄多组无激光与有激光的标定板图像，用PnP方法获取标定板在相机坐标系下的位姿，对有激光条纹的图片进行光条中心提取。PnP方法是通过已知n个控制点的空间位置信息以及他们的像点信息来计算这n个点在相机坐标系下的位置姿态。根据标定板提供的平面约束可解算光条中心的物理坐标值，用最小二乘优化方法拟合出光条中心的物理坐标所在的光刀平面Ax+By+Cz+D＝0。视觉传感器的测量坐标建立在激光光刀平面上，摄像机光心到激光光刀平面的垂足为测量坐标系原点，平行于激光平面的方向为z轴，平行于摄像机与激光平面的基线方向为y轴，两者叉乘为x轴，获得光刀平面坐标系。结合相机的内参矩阵和光刀平面坐标系可构建从激光条纹的图像像素坐标到实际物理坐标值的物理尺寸的转化矩阵。The calibrated cameras are used to capture multiple sets of images of the calibration board without laser and with laser in the measurement space. The PnP method is used to obtain the pose of the calibration board in the camera coordinate system, and the center of the light strip is extracted from the pictures with laser stripes. The PnP method calculates the position and attitude of the n points in the camera coordinate system by knowing the spatial position information of the n control points and their image point information. According to the plane constraints provided by the calibration board, the physical coordinates of the center of the light bar can be calculated, and the least squares optimization method is used to fit the light knife plane Ax+By+Cz+D=0 where the physical coordinates of the center of the light bar are located. The measurement coordinates of the vision sensor are established on the laser light knife plane. The vertical foot from the camera optical center to the laser light knife plane is the origin of the measurement coordinate system. The direction parallel to the laser plane is the z-axis, and the baseline direction parallel to the camera and the laser plane is the y-axis. , the cross product of the two is the x-axis, and the light-knife plane coordinate system is obtained. Combining the camera's internal parameter matrix and the light-knife plane coordinate system, the transformation matrix from the image pixel coordinates of the laser stripe to the physical size of the actual physical coordinate value can be constructed.
具体地，所述根据所述相机参数以及所述测量参数对所述第一视觉传感器和所述第二视觉传感器分别进行运动方向标定，分别得到所述第一视觉传感器和所述第二视觉传感器的测量坐标系的Y轴与实际运动方向的偏移量包括：Specifically, according to the camera parameters and the measurement parameters, the first visual sensor and the second visual sensor are respectively calibrated for movement directions, and the first visual sensor and the second visual sensor are obtained respectively. The offset between the Y axis of the measurement coordinate system and the actual motion direction includes:
将所述第一视觉传感器和所述第二视觉传感器分别在移动模组上移动多个位置，且在移动的每个位置上进行标定板的拍摄；Moving the first visual sensor and the second visual sensor to multiple positions on the mobile module, and photographing the calibration plate at each position of the movement;
获取标定板的位姿；Get the pose of the calibration board;
分别计算所述第一视觉传感器的每个位置的相对姿态变换以及和所述第二视觉传感器的每个位置的相对姿态变换；Calculate the relative attitude transformation of each position of the first vision sensor and the relative attitude transformation of each position of the second vision sensor respectively;
求解运动方向在相机坐标系下的方向向量；Solve the direction vector of the motion direction in the camera coordinate system;
输出所述方向向量。The direction vector is output.
下面结合图5所示对运动方向标定进行详细说明。The movement direction calibration will be described in detail below with reference to FIG. 5 .
由于叶片数字化样板检测装置的视觉传感器与线性模组在安装过程中必然存在误差，无法保证测量坐标系的y轴与实际运动方向一致，所以需要标定出运动方向。线性模组搭载视觉传感器移动多个位置拍摄标定板，根据对应性信息用PnP估计标定板的位姿，计算视觉传感器的相对姿态变换，求解运动方向在摄像机测量坐标系下的方向向量。如果视觉传感器按照测量要求倾斜安装，依旧利用上述方法标定出实际运动方向。Since the visual sensor of the blade digital template detection device and the linear module must have errors during the installation process, it cannot be guaranteed that the y-axis of the measurement coordinate system is consistent with the actual movement direction, so the movement direction needs to be calibrated. The linear module is equipped with a vision sensor to move multiple positions to shoot the calibration board. According to the corresponding information, PnP is used to estimate the pose of the calibration board, calculate the relative attitude transformation of the vision sensor, and solve the direction vector of the movement direction in the camera measurement coordinate system. If the vision sensor is installed obliquely according to the measurement requirements, still use the above method to calibrate the actual movement direction.
具体地，所述对所述第一视觉传感器和所述第二视觉传感器进行位置关系标定包括：Specifically, the calibrating the positional relationship between the first visual sensor and the second visual sensor includes:
所述第一视觉传感器和所述第二视觉传感器同时扫描测量空间中标定球的若干位置；The first visual sensor and the second visual sensor simultaneously scan several positions of the calibration sphere in the measurement space;
分别三维重建拟合出标定球在不同位置的球心坐标；Respectively reconstruct and fit the sphere center coordinates of the calibration sphere at different positions;
利用刚体变化求出所述第一视觉传感器和所述第二视觉传感器之间的位置关系。The positional relationship between the first vision sensor and the second vision sensor is obtained using the rigid body change.
下面结合图6对两个视觉传感器之间的位置关系标定进行详细说明。The calibration of the positional relationship between the two vision sensors will be described in detail below with reference to FIG. 6 .
两个视觉传感器同时扫描测量空间中标定球的若干位置，三维重建拟合出标定球在不同位置的球心坐标，利用刚体变换的方法求出设备之间的位置关系。Two vision sensors simultaneously scan several positions of the calibration sphere in the measurement space, and 3D reconstruction fits the sphere center coordinates of the calibration sphere at different positions, and uses the method of rigid body transformation to obtain the positional relationship between the devices.
具体地，对叶片数字化样板检测系统进行系统坐标系标定包括：Specifically, the system coordinate system calibration of the blade digital template detection system includes:
将标定球放置在转台边缘；Place the calibration ball on the edge of the turntable;
通过所述第一视觉传感器扫描重建拟合出所述标定球的球心坐标；The coordinates of the center of the calibration sphere are obtained by scanning and reconstructing the first visual sensor;
保持标定球与转台相对静止，旋转转台，并重复扫描重建拟合的步骤得到所述标定球在多个位置的球心坐标；Keep the calibration ball and the turntable relatively stationary, rotate the turntable, and repeat the steps of scanning, reconstructing and fitting to obtain the spherical center coordinates of the calibration ball at multiple positions;
拟合出转台旋转轴和旋转中心，得到系统坐标系，并得到测量坐标系与系统坐标系的转换关系。The rotation axis and rotation center of the turntable are fitted, and the system coordinate system is obtained, and the conversion relationship between the measurement coordinate system and the system coordinate system is obtained.
下面结合图7对系统坐标系标定进行详细说明。The calibration of the system coordinate system will be described in detail below with reference to FIG. 7 .
将标定球放置在转台边缘，用一台视觉传感器扫描重建拟合出球心坐标，旋转转台，重复以上动作得到多个位置的球心坐标，拟合出转台旋转轴与旋转中心，可求出转台坐标系即系统坐标系的z轴与原点，摄像机光轴方向与z轴叉乘方向为x轴，z轴与x轴叉乘方向为y轴。标定得出测量坐标系与系统坐标系的转换关系。Place the calibration ball on the edge of the turntable, scan and reconstruct the coordinates of the center of the sphere with a vision sensor, rotate the turntable, repeat the above actions to obtain the coordinates of the center of the sphere at multiple positions, and fit the rotation axis and center of the turntable, which can be calculated The turntable coordinate system is the z-axis and the origin of the system coordinate system, the cross-multiplication direction between the camera optical axis and the z-axis is the x-axis, and the cross-multiplication direction between the z-axis and the x-axis is the y-axis. The calibration obtains the conversion relationship between the measurement coordinate system and the system coordinate system.
优选地，所述第一视觉传感器的相机坐标系包括Pc1(Xc1，Yc1，Zc1)，所述第一视觉传感器的测量坐标系包括Pl1(Xl1，Yl1，Zl1)，所述第二视觉传感器的相机坐标系包括Pc2(Xc2，Yc2，Zc2)，所述第二视觉传感器的测量坐标系包括Pl2(Xl2，Yl2，Zl2)。Preferably, the camera coordinate system of the first vision sensor includes P c1 (X c1 , Y c1 , Z c1 ), and the measurement coordinate system of the first vision sensor includes P l1 (X l1 , Y l1 , Z l1 ) , the camera coordinate system of the second vision sensor includes P c2 (X c2 , Y c2 , Z c2 ), and the measurement coordinate system of the second vision sensor includes P l2 (X l2 , Y l2 , Z l2 ).
优选地，所述叶片数字化样板检测系统的系统坐标系包括Ps(Xs，Ys，Zs)。Preferably, the system coordinate system of the blade digital template detection system includes P s (X s , Y s , Z s ).
下面对本发明提供的叶片数字化样板检测系统的标定方法的具体实施过程进行说明。The specific implementation process of the calibration method of the blade digital template detection system provided by the present invention will be described below.
如图3所示，叶片数字化样板检测系统的标定方法的标定顺序依次为迭代摄像机标定、激光光刀平面标定、测量运动方向标定、传感器相对位置关系标定、系统坐标系标定。标定板采用圆环图案特征的陶瓷标定板，圆环行列分布为11×14，间隔15mm。标定球为理论直径50mm，实际经三坐标测量为49.978mm的哑光陶瓷标定球。As shown in Figure 3, the calibration sequence of the calibration method of the blade digital template detection system is iterative camera calibration, laser light knife plane calibration, measurement movement direction calibration, sensor relative position relationship calibration, and system coordinate system calibration. The calibration plate adopts a ceramic calibration plate with circular pattern features, and the circles are distributed in rows and columns of 11×14 with an interval of 15mm. The calibration ball is a matte ceramic calibration ball with a theoretical diameter of 50mm and an actual three-coordinate measurement of 49.978mm.
上述迭代摄像机标定的具体内容为拍摄不同位姿下的标定板图片，利用OpenCV函数获取摄像机标定用数据，再根据张正友摄像机标定方法获得相机内外参，将原始图像转换到标定板与图像平面平行的视图上，进行手动选择ROI区域对圆环中心点检测，将得到的圆环中心点转换到原始图像点，利用对应数据再次进行相机标定。重复上述过程直到标定精度不再提高，得到相机的内外参数。The specific content of the above iterative camera calibration is to take pictures of the calibration board in different poses, use the OpenCV function to obtain the data for camera calibration, and then obtain the internal and external parameters of the camera according to Zhang Zhengyou's camera calibration method, and convert the original image to the calibration board and the image plane. On the view, manually select the ROI area to detect the center point of the ring, convert the obtained center point of the ring to the original image point, and use the corresponding data to calibrate the camera again. The above process is repeated until the calibration accuracy is no longer improved, and the internal and external parameters of the camera are obtained.
激光光刀平面标定具体流程如图4所示，在测量空间中拍摄多组无激光与有激光的标定板图像，每组照片先拍摄无激光标定板图像，保持标定板与相机位置不动，调小曝光后，拍摄相同位姿下带有激光光条的标定板图像。用PnP方法获取标定板在相机坐标系下的位姿，对有激光条纹的图片进行光条中心提取。根据标定板提供的平面约束可解算光条中心的物理坐标值，用最小二乘优化方法拟合出光条中心的物理坐标所在的光刀平面方法Ax+By+Cz+D＝0。建立测量坐标系在相机坐标系下的表示，[R，T]LaserInCam＝[Xaxis Yaxis Zaxis]，[Ox Oy Oz]T]，其中[Ox Oy Oz]T是摄像机光心到激光光刀平面垂足在相机坐标系下的表示，垂足通过直线[At Bt Ct]T，其中t为自由标量，带入激光平面方程为
测量运动方向标定流程如图5所示，目的是为了标定测量坐标系Y轴与实际运动方向的偏差，其实质还是在确立视觉传感器测量坐标系。保持标定板静止在视场中，使叶片数字化样板测量装置的线性模组搭载视觉传感器每移动一小段距离就拍摄图片，使用PnP方法获得视觉传感器移动到不同位置的标定板位姿，得到运动方向在相机坐标系下的方向向量cYm，其在测量坐标系下的表示为lYm＝lRc cYm，其中为相机坐标系在激光测量坐标系下的旋量lRc。当线性模组移动L时，测量坐标系相对于实际扫描坐标系的变换关系为
两个视觉传感器之间的相对位置关系标定流程如图6所示，将标定球放置在叶片数字化样板检测装置的视场中任意位置，同时用两个视觉传感器扫描重建标定球的点云，各自重建多个位置后，用最小二乘法拟合球心，通过两个视觉传感器实际扫描坐标系下的三维坐标建立刚体变换关系。The calibration process of the relative position relationship between the two vision sensors is shown in Figure 6. The calibration ball is placed at any position in the field of view of the blade digital template detection device, and the point cloud of the calibration ball is scanned and reconstructed with two vision sensors. After reconstructing multiple positions, the least squares method is used to fit the center of the sphere, and the rigid body transformation relationship is established by actually scanning the three-dimensional coordinates in the coordinate system through the two vision sensors.
系统坐标系标定流程如图7所示，在转台靠近边缘的位置放置标定球，利用第一视觉传感器扫描重建标定球点云，保持标定球相对转台位置不动，旋转转台一个角度后重复以上操作，用多个角度的球心坐标最小拟合转台圆平面，以转台平面法向向上作为系统坐标系的Z轴，以相机光轴方向和Z轴叉乘方向作为X轴，Y轴为Z轴与X轴叉乘。同时得到转台中心坐标S＝[Xs Ys Zs]和系统坐标系在相机坐标系下的变换矩阵cRTs。当导轨移动Hc时相机坐标系相对扫描坐标系的变换为
通过标定软件拟合球心交互界面可以显示出，所有标定功能都集成于一体，拍摄的图片于扫描重建的点云会自动保存于相应标定文件夹内。三维显示点云后，可实时对点云进行保存、拟合球心、重新选择点云、选取点并显示坐标等交互，拟合后的信息显示在信息栏中。Through the calibration software fitting the spherical center interactive interface, it can be shown that all calibration functions are integrated into one, and the point cloud captured and scanned and reconstructed will be automatically saved in the corresponding calibration folder. After the point cloud is displayed in three dimensions, the point cloud can be saved in real time, fitted to the center of the sphere, re-selected point cloud, selected point and displayed coordinates, etc. The fitted information is displayed in the information bar.
叶片数字化样板检测装置的测量范围为(1000×400×250)mm，测量深度为200mm至400mm，CCD相机应具有较高的拍摄帧率与较高的分辨率，选用规格为149fps与1280×1024，基线距离为240mm，成像角38.7°，重量为3.5kg，镜头选用焦距为8.0mm，分辨率为120.001p/mm，畸变率为0.60％，线激光器功率为100mw，发散角60°。系统标定完成后，对系统作视觉传感器重复性误差评价和系统测量误差评价。传感器重复性误差评价是将视觉传感器的激光固定打在标准球的某个位置，在该位置拍摄提取激光光条中心200次，计算每个激光条纹点200次的Y轴上下跳动的最大误差、均值、标准差，并且统计标准球在转盘不同位置的光条提取重复性。采用测试的标准球材质为普通陶瓷球与哑光陶瓷球，在相同位置对两种标准球作效果对比，哑光陶瓷球的抗反光能力比普通陶瓷球好，激光提取效果更佳。光条检测y坐标重复性普通陶瓷球为0.054像素，哑光陶瓷球为0.019像素。系统测量误差评价是扫描重建理论直径为50mm、球心距为500mm的标准球棒多组，每组15次，经三坐标测量球棒中球径为49.978mm、49.974mm，球心距为500.303mm，拟合球直径与两个标准球的球心距。拟合的球径均值为50.028mm，标准差为0.0558mm，拟合的球心距均值为500.254mm，标准差为0.071mm。综上述，经过完整系统标定后，叶片数字化样板检测装置的系统测量精度＜0.08mm。The measurement range of the blade digital sample detection device is (1000×400×250)mm, and the measurement depth is 200mm to 400mm. The CCD camera should have a higher shooting frame rate and higher resolution, and the selected specifications are 149fps and 1280×1024 , the baseline distance is 240mm, the imaging angle is 38.7°, the weight is 3.5kg, the focal length of the lens is 8.0mm, the resolution is 120.001p/mm, the distortion rate is 0.60%, the line laser power is 100mw, and the divergence angle is 60°. After the system calibration is completed, the visual sensor repeatability error evaluation and the system measurement error evaluation are performed on the system. The sensor repeatability error evaluation is to fix the laser of the vision sensor at a certain position of the standard ball, shoot and extract the center of the laser stripe 200 times at this position, and calculate the maximum error of the Y-axis up and down beating of each laser stripe point 200 times, Mean, standard deviation, and repeatability of light bar extraction of statistical standard spheres at different positions on the turntable. The test standard balls are made of ordinary ceramic balls and matte ceramic balls. Comparing the effects of the two standard balls at the same position, the anti-reflection ability of the matte ceramic balls is better than that of ordinary ceramic balls, and the laser extraction effect is better. The y-coordinate repeatability of light bar detection is 0.054 pixels for ordinary ceramic balls and 0.019 pixels for matte ceramic balls. The systematic measurement error evaluation is to scan and reconstruct several groups of standard bats with a theoretical diameter of 50mm and a center-to-center distance of 500mm, 15 times per group. The three-coordinate measurement of the ball diameter of the bat is 49.978mm, 49.974mm, and the center-to-center distance is 500.303 mm, the fitted ball diameter and the center-to-center distance of the two standard balls. The mean diameter of the fitted balls is 50.028mm, the standard deviation is 0.0558mm, the mean value of the fitted ball center distance is 500.254mm, and the standard deviation is 0.071mm. In summary, after the complete system calibration, the system measurement accuracy of the blade digital template detection device is less than 0.08mm.
因此，本发明提供的叶片数字化样板检测系统的标定方法，操作简单，操作人员只需要准备一个通用标定板和标定球，无需制作特定标定块，降低标定成本，利用标定板拍摄摄像机标定、激光平面标定、测量运动方向标定的图片，利用标定球扫描重建设备之间位置关系标定、系统坐标系标定的点云数据文件，按照标定软件提示操作，即可得到每个标定项目的输出结果。Therefore, the calibration method of the blade digital template detection system provided by the present invention is simple to operate, and the operator only needs to prepare a general calibration plate and calibration ball, no need to make a specific calibration block, and the calibration cost is reduced. The calibration plate is used to shoot camera calibration, laser plane Calibrate and measure the pictures of movement direction calibration, use the calibration ball to scan and reconstruct the point cloud data files of the position relationship calibration between the devices and the system coordinate system calibration, and operate according to the prompts of the calibration software, and then the output results of each calibration project can be obtained.
另外，本发明提供的叶片数字化样板检测系统的标定方法具有标定效率高，测量运动方向标定直接利用线性模组的运动，无需额外高精度运动机构。设备之间位置关系标定、系统坐标系标定中点云显示、拟合球心、交互操作集成于标定软件中，无需利用第三方软件进行点云球心拟合。所有标定好的结果自动加入叶片数字化样板检测装置的测量软件中，标定完即可进行测量工作。In addition, the calibration method of the blade digital template detection system provided by the present invention has the advantages of high calibration efficiency, and the movement of the linear module is directly used for the calibration of the measurement movement direction, and no additional high-precision movement mechanism is required. The calibration of the position relationship between the devices, the display of the point cloud in the system coordinate system calibration, the fitting of the sphere center, and the interactive operation are integrated into the calibration software, and there is no need to use third-party software for point cloud sphere center fitting. All the calibrated results are automatically added to the measurement software of the blade digital template detection device, and the measurement can be carried out after the calibration.
作为本发明的第二个方面，提供一种叶片数字化样板检测系统的标定装置，其中，如图8所示，所述叶片数字化样板检测系统的标定装置10包括：As a second aspect of the present invention, a calibration device of a blade digital template detection system is provided, wherein, as shown in FIG. 8 , the
摄像机标定模块110，所述摄像机标定模块110用于对所述第一视觉传感器和所述第二视觉传感器分别进行摄像机标定得到相机坐标系下的相机参数；a
激光光刀平面标定模块120，所述激光光刀平面标定模块120用于对所述第一视觉传感器和所述第二视觉传感器分别进行激光光刀平面标定得到测量坐标系下的测量参数；Laser light knife
运动方向标定模块130，所述运动方向标定模块130用于根据所述相机参数以及所述测量参数对所述第一视觉传感器和所述第二视觉传感器分别进行运动方向标定，分别得到所述第一视觉传感器和所述第二视觉传感器的测量坐标系的Y轴与实际运动方向的偏移量；A movement
第一转换模块140，所述第一转换模块140用于分别将所述第一视觉传感器和所述第二视觉传感器的所述相机参数由所述相机坐标系转换到所述测量坐标系，成为所述测量坐标系中的测量参数；The
位置关系标定模块150，所述位置关系标定模块150用于对所述第一视觉传感器和所述第二视觉传感器进行位置关系标定；a positional
第二转换模块160，所述第二转换模块160用于将所述第二视觉传感器的测量坐标系下的测量参数转换到所述第一视觉传感器的测量坐标系下；a
系统坐标系标定模块170，所述系统坐标系标定模块170用于对叶片数字化样板检测系统进行系统坐标系标定；a system coordinate
第三转换模块180，所述第三转换模块180用于将所述第一视觉传感器下的测量坐标系转换到叶片数字化样板检测系统的系统坐标系下，得到所述叶片数字化样板检测系统的系统坐标系下的完整参数。The
本发明提供的叶片数字化样板检测系统的标定装置，用于对能够快速扫描叶片型面、获取叶片完整点云、自动分析测量参数、输出检测报告的叶片数字化样板检测装置进行系统标定。通过通用标定标靶对所述装置快速完成摄像机标定、激光光刀平面标定、测量运动方向标定、设备位置关系标定、系统坐标系标定，使得准确获取各坐标系之间的相互转化关系，降低标定成本，实现了完整标定，且能够提高整个系统的标定效率，简化系统标定的流程，实现了叶片数字化样板测量装置的适用性。The calibration device of the blade digital template detection system provided by the invention is used for systematic calibration of the blade digital template detection device which can quickly scan the blade profile, obtain the complete point cloud of the blade, automatically analyze the measurement parameters, and output the detection report. The device can quickly complete the camera calibration, laser light knife plane calibration, measurement movement direction calibration, equipment position relationship calibration, and system coordinate system calibration through the universal calibration target, so that the mutual transformation relationship between each coordinate system can be accurately obtained and the calibration cost can be reduced. , realizes complete calibration, and can improve the calibration efficiency of the whole system, simplify the process of system calibration, and realize the applicability of the blade digital template measurement device.
关于本发明提供的叶片数字化样板检测系统的标定装置的工作原理可以参照前文的描述，此处不再赘述。Regarding the working principle of the calibration device of the blade digital template detection system provided by the present invention, reference may be made to the foregoing description, which will not be repeated here.
可以理解的是，以上实施方式仅仅是为了说明本发明的原理而采用的示例性实施方式，然而本发明并不局限于此。对于本领域内的普通技术人员而言，在不脱离本发明的精神和实质的情况下，可以做出各种变型和改进，这些变型和改进也视为本发明的保护范围。It can be understood that the above embodiments are only exemplary embodiments adopted to illustrate the principle of the present invention, but the present invention is not limited thereto. For those skilled in the art, without departing from the spirit and essence of the present invention, various modifications and improvements can be made, and these modifications and improvements are also regarded as the protection scope of the present invention.
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Application publication date: 20181120 Assignee: Jiangsu Jihui Huake Intelligent Equipment Technology Co., Ltd. Assignor: Wuxi research institute of the Central China University of Science and Technology Contract record no.: X2019980000288 Denomination of invention: Calibration method and device of blade digitalized templet detection system License type: Common License Record date: 20191023 |
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Effective date of registration: 20210106 Address after: 214174 A216, No.2 Qingyan Road, Huishan Economic Development Zone, Wuxi City, Jiangsu Province Patentee after: Jiangsu Jihui Huake Intelligent Equipment Technology Co.,Ltd. Address before: 214100 no.329 Yanxin Road, Huishan District, Wuxi City, Jiangsu Province Patentee before: HUST-WUXI Research Institute |