CN112082483B - Positioning method and application of workpiece with edge characteristics only and precision evaluation method - Google Patents
Positioning method and application of workpiece with edge characteristics only and precision evaluation method Download PDFInfo
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Abstract
The invention discloses a method for positioning a workpiece with only edge characteristics, which comprises the following steps: the robot drives the single-line structured light sensor to detect the standard workpiece, standard data are calibrated, and a light plane equation of each test position is recorded; during testing, the robot drives the single-line structured light sensor to obtain three-dimensional coordinates of each test point on the actually measured workpiece at different test positions, and the three-dimensional coordinates are recorded as actually measured data; calculating a rotation translation matrix based on the calibrated three-dimensional coordinates and the measured data; performing rotational translation on each auxiliary straight line, and recording the intersection points of the auxiliary straight lines and the corresponding optical plane equations into a calibration point set; taking the distance between corresponding points of the measured data and the calibration point set as a target function, and iterating by using an optimization method to obtain an optimal rotation translation matrix meeting a convergence condition; compensating the coordinates of the test points in the calibration process to obtain the position of the current workpiece, and completing positioning; the method effectively solves the problems of edge test point deviation and inaccurate positioning, and improves the accuracy of visual positioning.
Description
Technical Field
The invention relates to the field of structured light measurement, in particular to a positioning method, application and precision evaluation method of a workpiece with only edge characteristics.
Background
In the field of active vision measurement, structured light measurement is a common measurement method, wherein the most widely used is line laser characteristics, it projects laser stripes to a measured object through a line laser, adopts an image acquisition device to acquire images of the stripes, three-dimensional information of the measured object is obtained through image analysis, when the line-structured light sensor is used for visual positioning, the characteristics of the object to be measured need to be selected, and the characteristics are extracted to obtain three-dimensional information, so as to realize visual positioning, in practical use, visual positioning is often applied to the field of visual guidance or automatic processing and assembly, workpieces of the same type are sequentially placed on a station to be measured through a production line, a rotating wheel, a roller bed and other mobile equipment, in the process, the actual position of the workpiece to be measured and the position of the standard workpiece are inevitably different under the influence of the transmission precision of the mobile equipment, the positioning error of the tool clamp and the processing precision among different workpieces; the existing positioning method only calculates the rotation translation relation between the measured point coordinates (selected measured characteristic coordinates) on the workpiece to be measured and the measured point coordinates on the standard workpiece, if the measured characteristics are in a closed shape (such as characteristic circles, square holes or balls), the positioning is carried out according to the geometric center of the graphic characteristics, at the moment, the position of the measured object slightly moves to have limited influence on the measured characteristics, so as to ensure that the laser bar can cover the measured characteristics, and even if small errors exist between the characteristics of the current measured object and the characteristic positions on the standard workpiece, the geometric center of the measured characteristics can still be obtained through structured light; however, workpieces to be measured are various in types, some workpieces do not contain closed graphic features, such as a flat plate, an automobile roof and a windshield glass frame, the workpieces only contain surface features and edge features, structural light measurement is adopted, the edge features need to be selected for workpiece positioning, the edge is a stretching body, points selected on the edge are not visually and obviously different from surrounding points, and as long as the position of the workpiece to be measured is changed (deviated and rotated), errors exist between the measuring points of the current workpiece and the measuring points of the standard workpiece, and the consistency of the measuring points before and after deviation cannot be ensured.
Disclosure of Invention
In order to solve the problems, the invention provides a workpiece visual positioning method based on single-line structured light, which improves the existing positioning method by utilizing an optimization idea, effectively solves the problems of edge test point deviation and inaccurate positioning, and improves the accuracy of visual positioning.
The technical scheme is as follows:
the positioning method of the workpiece with only the edge characteristic comprises the steps that at least two edges which are not on the same straight line are formed on the surface of the workpiece with only the edge characteristic; the method comprises the following steps:
the robot drives the single-line structured light sensor to detect the standard workpiece at a plurality of different test positions, and the test result at least comprises three points on edges which are not on the same straight line (the three-dimensional coordinate of the middle point of the test result can monitor the deviation of the workpiece along X, Y, Z three directions and the rotation of the workpiece around X, Y, Z three axes (namely, the principle of establishing a system and selecting points at 321) is met); before testing, calibrating the auxiliary linear equation of each testing position and the three-dimensional coordinates of the testing points, taking the auxiliary linear equation and the three-dimensional coordinates as standard data, and simultaneously converting the optical plane equation of the single-line structured light sensor of each testing position into a space coordinate system and recording the optical plane equation;
the test points and the auxiliary straight lines corresponding to the test positions are obtained by the following method: at the test position, the inflection point of the single-line structured light stripe on the standard workpiece is a test point; obtaining a plurality of points on the same edge by finely adjusting the positions of the robot by taking the test points as a reference, and fitting the points with the three-dimensional coordinates of the corresponding test points to obtain auxiliary straight lines;
during testing, workpieces with the same type as the standard workpieces are placed on a detection station according to a preset state, and the robot drives the single-line structured light sensor to obtain three-dimensional coordinates of each test point at different test positions according to a preset path, and the three-dimensional coordinates are recorded as measured data;
calculating a rotation translation matrix based on the three-dimensional coordinates of the test points recorded in the calibration process and the three-dimensional coordinate data of the test points in the measured data; on the basis, each auxiliary straight line in the standard data is subjected to rotational translation, and then the intersection points of the auxiliary straight line and the corresponding optical plane equation are recorded into a calibration point set;
taking the three-dimensional coordinates of each test point in the measured data and the distance between the intersection points in the corresponding calibration point set as a target function, and iterating by using an optimization method to obtain an optimal rotation translation matrix meeting the convergence condition;
and compensating the optimal rotation and translation matrix to the coordinates of each test point in the calibration process to obtain the position of the current workpiece, and finishing positioning.
In order to ensure that the edge of the workpiece acquired and actually measured by the sensor and the edge of the standard workpiece are the same-side edges, further, when the workpiece is placed on a detection station according to a preset state, the deviation between the workpiece and the standard workpiece in the calibration time in the transverse and longitudinal directions is within 30mm, and the deviation of the angle is within 5 degrees.
Further, the optimization method is a gradient descent method, an LM method, or a gauss-newton method.
Further, the objective function is represented as min { S }i-Fi1,2 … … m, m represents test point number, SiRepresenting the three-dimensional coordinates of the test points in the measured data of the ith test position, FiThree-dimensional representation of intersections in set of i-th test position calibration pointsCoordinates;
the convergence conditions are as follows: a unique upper limit value or an upper limit value of 1 objective function for each test position.
As an application, the positioning method of the present invention is used for workpiece gripping, including: and compensating the optimized rotation and translation matrix to the grabbing track of the grabbing robot, and guiding the grabbing robot to grab the workpiece according to the actual position.
As another application, the positioning method of the present invention is used for workpiece processing, including: and compensating the optimized rotation and translation matrix to the processing track of the processing robot, and guiding the workpiece grabbing robot to process the workpiece (such as welding, cutting and the like) according to the actual position.
The invention also discloses a method for evaluating the precision of the positioning method, which comprises the following steps:
s1, acquiring three-dimensional coordinates Q of specific points on the standard workpiece by using a standard instrumentjJ is 1,2 … … n, n represents the number of feature points; the standard instrument comprises a laser tracker, a three-coordinate machine and V-Sarrs; the specific points are points marked on the surface or edge of the standard workpiece in advance and at least comprise three non-collinear points;
the robot drives the single-line structured light sensor to detect the standard workpiece at a plurality of different test positions, and the test result at least comprises three points on edges which are not on the same straight line; before testing, calibrating the auxiliary linear equation of each testing position and the three-dimensional coordinates of the testing points, taking the auxiliary linear equation and the three-dimensional coordinates as standard data, and simultaneously converting the optical plane equation of the single-line structured light sensor of each testing position into a space coordinate system and recording the optical plane equation;
the test points and the auxiliary straight lines corresponding to the test positions are obtained by the following method: at the test position, the inflection point of the single-line structured light stripe on the standard workpiece is a test point; obtaining a plurality of points on the same edge by finely adjusting the positions of the robot by taking the test points as a reference, and fitting the points with the three-dimensional coordinates of the corresponding test points to obtain auxiliary straight lines;
s2, adjusting the positions of the standard workpieces to present the positions of other workpieces when placed;
and (5) acquiring the three-dimensional coordinates Q 'of the specific point on the adjusted standard workpiece again by using a standard instrument'jSolving for Q 'by rigid body transformation'jAnd QjA rotational translation matrix RT' in between; (wherein, Q'jAnd QjAll under a global space coordinate system)
The robot drives the single-line structured light sensor to obtain three-dimensional coordinates of each test point at different test positions according to a preset path, and the three-dimensional coordinates are recorded as measured data;
calculating a rotation translation matrix based on the three-dimensional coordinates of the test points recorded in the calibration process and the three-dimensional coordinate data of the test points in the measured data; on the basis, each auxiliary straight line in the standard data is subjected to rotational translation, and then the intersection points of the auxiliary straight line and the corresponding optical plane equation are recorded into a calibration point set;
taking the three-dimensional coordinates of each test point in the measured data and the distance between the intersection points in the corresponding calibration point set as a target function, and iterating by using an optimization method to obtain an optimal rotation translation matrix RT meeting the convergence condition;
s3, comparing the RT and the RT ', judging whether the difference value between the rotation component and the translation component between the RT and the RT' is smaller than a preset value, if so, the obtained optimal rotation and translation matrix RT meets the measurement requirement, and if not, the optimal rotation and translation matrix RT cannot meet the measurement requirement.
The scheme of the invention has the following advantages:
(1) the method comprises the steps of solving an initial rotation translation relation by using coordinates of test points, performing straight line fitting around each test point, wherein a fitted auxiliary straight line represents an edge line, when the actual position of a workpiece is changed, the position of the test point is changed but the corresponding auxiliary straight line is not changed all the time, adjusting the auxiliary straight line by using the initial rotation translation relation, theoretically, the intersection point of the adjusted auxiliary straight line and a light plane should be consistent with the actual measurement coordinates of the corresponding position, setting a target function and providing convergence conditions based on the principle, obtaining a more accurate rotation translation matrix based on the optimized idea, and further realizing high-precision positioning; the method is applied to visual guidance, and can assist the robot in precise workpiece grabbing, processing and the like;
(2) the invention also provides a precision verification method, which adopts a standard instrument and a single-line structured light sensor to respectively measure a standard workpiece before and after position adjustment, compares the rotation and translation matrixes obtained twice, effectively evaluates the positioning precision of the positioning method and screens the sensors meeting the detection requirements.
Drawings
FIG. 1 is a schematic diagram showing the change of the position of a measuring point between a workpiece to be measured and a standard workpiece;
FIG. 2 is a schematic view of a light plane at multiple projection laser bars and station locations;
fig. 3 is a schematic diagram of a captured single line structured light image.
Detailed Description
The technical solution of the present invention is described in detail below with reference to the accompanying drawings and the detailed description.
A positioning method of a workpiece with only edge characteristics is characterized in that at least two edges which are not on the same straight line are formed on the surface of the workpiece with only edge characteristics; the method comprises the following steps:
the robot drives the single-line structured light sensor to detect the standard workpiece at a plurality of different test positions, and the test result at least comprises three points on edges which are not on the same straight line (preferably, the three-dimensional coordinate of the middle point of the test result can monitor the deviation of the workpiece along X, Y, Z three directions and the rotation of the workpiece around X, Y, Z three axes (namely, the principle of establishing a system and selecting points at 321) is met); before testing, calibrating the auxiliary linear equation of each testing position and the three-dimensional coordinates of the testing points, taking the three-dimensional coordinates as standard data, converting the optical plane (shown in figure 2) equation of the single-line structured light sensor of each testing position into a space coordinate system (the embodiment is arranged in a robot base coordinate system), and recording;
the test points and the auxiliary straight lines corresponding to the test positions are obtained by the following method: at the test position, the inflection point of the single-line structured light stripe on the standard workpiece is a test point; as for the calculation of the coordinates of the measuring points in fig. 3, according to the quality of the collected image, the coordinates of the end point (point a or point B) at any end of the break inflection point part of the laser bar are selected, in this embodiment, the coordinates of the end point B at the lower edge of the break inflection point part of the laser bar are calculated;
obtaining a plurality of points on the same edge by finely adjusting the positions of the robot by taking the test points as a reference, and fitting the points with the three-dimensional coordinates of the corresponding test points to obtain auxiliary straight lines; (in specific implementation, the robot moves 3-10 times, the single-line structured light sensor respectively emits laser (as shown in figure 2: the robot moves 9 times, the projected 9 laser strips are displayed simultaneously), an auxiliary straight line is obtained by resolving inflection points on the multiple laser strips, preferably, the laser strips projected by the single-line structured light sensor each time are parallel to the laser strips projected for the first time, and the distance between two adjacent laser strips is less than 5mm)
During testing, workpieces with the same type as the standard workpieces are placed on a detection station according to a preset state (as shown in fig. 1, the positions of the actually-measured workpieces and the standard workpieces are changed by pfzero pfmove), and the robot drives the single-line structured light sensor to obtain three-dimensional coordinates of each test point at different test positions according to a preset path and records the three-dimensional coordinates as actually-measured data;
calculating a rotation translation matrix based on the three-dimensional coordinates of the test points recorded in the calibration process and the three-dimensional coordinate data of the test points in the measured data; on the basis, each auxiliary straight line in the standard data is subjected to rotational translation, and then the intersection points of the auxiliary straight line and the corresponding optical plane equation are recorded into a calibration point set;
taking the three-dimensional coordinates of each test point in the measured data and the distance between the intersection points in the corresponding calibration point set as a target function, and iterating by using an optimization method to obtain an optimal rotation translation matrix meeting the convergence condition;
and compensating the optimal rotation and translation matrix to the coordinates of each test point in the calibration process to obtain the position of the current workpiece, and finishing positioning.
Specifically, a plurality of workpieces are provided, one workpiece is manually selected as a standard workpiece, and the other workpieces are workpieces to be tested; and acquiring standard data by using the standard workpiece, and respectively calculating an optimized rotation and translation matrix for positioning other workpieces to be measured.
In order to ensure that the edge of the workpiece acquired and actually measured by the sensor and the edge of the standard workpiece are the same-side edges, when the workpiece is placed on a detection station according to a preset state, the deviation between the workpiece and the standard workpiece in the transverse and longitudinal directions during calibration is within 30mm, and the deviation between the angle and the position is within 5 degrees.
Among them, the optimization method is a gradient descent method, an LM method, or a Gaussian Newton method.
Expressing the objective function as min Si-Fi1,2 … … m, m represents test point number, SiRepresenting the three-dimensional coordinates of the test points in the measured data of the ith test position, FiRepresenting the three-dimensional coordinates of the intersection points in the ith test position calibration point set;
the convergence conditions are as follows: a unique upper limit value or an upper limit value of 1 objective function for each test position.
In the specific operation: setting m distance upper limit values, and if the m distance values obtained by the target function are respectively smaller than the distance upper limit values of the corresponding positions, meeting a convergence condition;
or: and setting a distance upper limit total value, and if the sum or the mean value of the m distance values obtained by the target function is less than the distance upper limit total value, meeting a convergence condition.
As an application of the present embodiment, the workpiece grasping by using the positioning method includes: and compensating the optimized rotation and translation matrix to the grabbing track of the grabbing robot, and guiding the grabbing robot to grab the workpiece according to the actual position.
As another application of this embodiment, a positioning method for processing a workpiece includes: and compensating the optimized rotation and translation matrix to the processing track of the processing robot, and guiding the workpiece grabbing robot to process the workpiece (such as welding, cutting and the like) according to the actual position.
In order to evaluate the accuracy of the positioning method, a method for evaluating the accuracy of the positioning method is also disclosed, which comprises the following steps:
s1, acquiring three-dimensional coordinates Q of specific points on the standard workpiece by using a standard instrumentjJ is 1,2 … … n, n represents the number of feature points; the standard instrument comprises a laser tracker, a three-coordinate machine and V-Sarrs; the specific points being points marked beforehand on the faces or edges of the standard workpiece, including at least threePoints that are not collinear;
the robot drives the single-line structured light sensor to detect the standard workpiece at a plurality of different test positions, and the test result at least comprises three points on edges which are not on the same straight line; before testing, calibrating the auxiliary linear equation of each testing position and the three-dimensional coordinates of the testing points, taking the auxiliary linear equation and the three-dimensional coordinates as standard data, and simultaneously converting the optical plane equation of the single-line structured light sensor of each testing position into a space coordinate system and recording the optical plane equation;
the test points and the auxiliary straight lines corresponding to the test positions are obtained by the following method: at the test position, the inflection point of the single-line structured light stripe on the standard workpiece is a test point; obtaining a plurality of points on the same edge by finely adjusting the positions of the robot by taking the test points as a reference, and fitting the points with the three-dimensional coordinates of the corresponding test points to obtain auxiliary straight lines;
s2, adjusting the positions of the standard workpieces to present the positions of other workpieces when placed;
and (5) acquiring the three-dimensional coordinates Q 'of the specific point on the adjusted standard workpiece again by using a standard instrument'jSolving for Q 'by rigid body transformation'jAnd QjA rotational translation matrix RT' in between; (wherein, Q'jAnd QjAre all under a global space coordinate system (robot base coordinate system)
The robot drives the single-line structured light sensor to obtain three-dimensional coordinates of each test point at different test positions according to a preset path, and the three-dimensional coordinates are recorded as measured data;
calculating a rotation translation matrix based on the three-dimensional coordinates of the test points recorded in the calibration process and the three-dimensional coordinate data of the test points in the measured data; on the basis, each auxiliary straight line in the standard data is subjected to rotational translation, and then the intersection points of the auxiliary straight line and the corresponding optical plane equation are recorded into a calibration point set;
taking the three-dimensional coordinates of each test point in the measured data and the distance between the intersection points in the corresponding calibration point set as a target function, and iterating by using an optimization method to obtain an optimal rotation translation matrix RT meeting the convergence condition;
s3, comparing the RT and the RT ', judging whether the difference value between the rotation component and the translation component between the RT and the RT' is smaller than a preset value, if so, the obtained optimal rotation and translation matrix RT meets the measurement requirement, and if not, the optimal rotation and translation matrix RT cannot meet the measurement requirement.
In the embodiment, 5 times of precision verification is performed, that is, the pose of the standard workpiece is adjusted 5 times, each time of adjustment is measured by using a standard instrument and a single-line structured light sensor, a rotational translation matrix is respectively calculated, rotational translation components of the rotational translation matrix are obtained, difference values between the components of the conventional measurement method and the components of the method are respectively compared, and test data are shown in the following table, wherein dx, dy and dz represent translation components in X, Y, Z directions in the rotational translation matrix; rx, ry, rz represent the X, Y, Z three-directional rotational components in the rototranslation matrix; the difference between the translation components obtained by the traditional measurement method, the method and the standard instrument measurement represented by error _ dx, error _ dy and error _ dz; the difference between the rotation components obtained by the traditional measurement method, the method and the standard instrument measurement represented by error _ rx, error _ ry and error _ rz;
as can be seen from the table, each component value of the method is closer to the component value obtained by the measurement of a standard instrument, namely, a more accurate rotation and translation matrix is obtained, and compared with the traditional calculation method, the precision is obviously improved.
For convenience in explanation and accurate definition in the appended claims, the terms "upper", "lower", "inner" and "outer" are used to describe features of the exemplary embodiments with reference to the positions of such features as displayed in the figures.
The foregoing descriptions of specific exemplary embodiments of the present invention have been presented for purposes of illustration and description. The foregoing description is not intended to be exhaustive or to limit the invention to the precise form disclosed, and obviously many modifications and variations are possible in light of the above teaching. The exemplary embodiments were chosen and described in order to explain certain principles of the invention and its practical application to enable others skilled in the art to make and use various exemplary embodiments of the invention and various alternatives and modifications thereof. It is intended that the scope of the invention be defined by the following claims and their equivalents.
Claims (7)
1. The positioning method of the workpiece with only the edge characteristic comprises the steps that at least two edges which are not on the same straight line are formed on the surface of the workpiece with only the edge characteristic; the method is characterized in that:
the robot drives the single-line structured light sensor to detect the standard workpiece at a plurality of different test positions, and the test result at least comprises three points on edges which are not on the same straight line; before testing, calibrating the auxiliary linear equation of each testing position and the three-dimensional coordinates of the testing points, taking the auxiliary linear equation and the three-dimensional coordinates as standard data, and simultaneously converting the optical plane equation of the single-line structured light sensor of each testing position into a space coordinate system and recording the optical plane equation;
the test points and the auxiliary straight lines corresponding to the test positions are obtained by the following method: at the test position, the inflection point of the single-line structured light stripe on the standard workpiece is a test point; obtaining a plurality of points on the same edge by finely adjusting the positions of the robot by taking the test points as a reference, and fitting the points with the three-dimensional coordinates of the corresponding test points to obtain auxiliary straight lines;
during testing, workpieces with the same type as the standard workpieces are placed on a detection station according to a preset state, and the robot drives the single-line structured light sensor to obtain three-dimensional coordinates of each test point at different test positions according to a preset path, and the three-dimensional coordinates are recorded as measured data;
calculating a rotation translation matrix based on the three-dimensional coordinates of the test points recorded in the calibration process and the three-dimensional coordinate data of the test points in the measured data; on the basis, each auxiliary straight line in the standard data is subjected to rotational translation, and then the intersection points of the auxiliary straight line and the corresponding optical plane equation are recorded into a calibration point set;
taking the three-dimensional coordinates of each test point in the measured data and the distance between the intersection points in the corresponding calibration point set as a target function, and iterating by using an optimization method to obtain an optimal rotation translation matrix meeting the convergence condition;
and compensating the optimal rotation and translation matrix to the coordinates of each test point in the calibration process to obtain the position of the current workpiece, and finishing positioning.
2. The method of claim 1 for locating a workpiece having only edge features, comprising: when the workpiece is placed at the detection station according to a preset state, the deviation of the workpiece and the standard workpiece in the calibration time in the transverse and longitudinal directions is within 30mm, and the deviation of the angle is within 5 degrees.
3. The method of claim 1 for locating a workpiece having only edge features, comprising: the optimization method is a gradient descent method, an LM method or a Gaussian Newton method.
4. The method of claim 1 for locating a workpiece having only edge features, comprising: expressing the objective function as min Si-Fi1,2 … … m, m represents test point number, SiRepresenting the three-dimensional coordinates of the test points in the measured data of the ith test position, FiRepresenting the three-dimensional coordinates of the intersection points in the ith test position calibration point set;
the convergence conditions are as follows: a unique upper limit value or an upper limit value of 1 objective function for each test position.
5. A method for workpiece grabbing by using the positioning method as claimed in any one of claims 1 to 4, wherein the optimized rotation and translation matrix is compensated to a grabbing track of the grabbing robot, and the grabbing robot is guided to grab the workpiece according to the actual position.
6. A method for processing a workpiece by using the positioning method of any one of claims 1-4, wherein the optimized rotation and translation matrix is compensated to the processing track of the processing robot, and the workpiece-grabbing robot is guided to process the workpiece according to the actual position.
7. A method for evaluating the accuracy of the positioning method, comprising the steps of:
s1, acquiring three-dimensional coordinates Q of specific points on the standard workpiece by using a standard instrumentjJ is 1,2 … … n, n represents the number of feature points; the standard instrument comprises a laser tracker, a three-coordinate machine and V-Sarrs; the specific points are points marked on the surface or edge of the standard workpiece in advance and at least comprise three non-collinear points;
the robot drives the single-line structured light sensor to detect the standard workpiece at a plurality of different test positions, and the test result at least comprises three points on edges which are not on the same straight line; before testing, calibrating the auxiliary linear equation of each testing position and the three-dimensional coordinates of the testing points, taking the auxiliary linear equation and the three-dimensional coordinates as standard data, and simultaneously converting the optical plane equation of the single-line structured light sensor of each testing position into a space coordinate system and recording the optical plane equation;
the test points and the auxiliary straight lines corresponding to the test positions are obtained by the following method: at the test position, the inflection point of the single-line structured light stripe on the standard workpiece is a test point; obtaining a plurality of points on the same edge by finely adjusting the positions of the robot by taking the test points as a reference, and fitting the points with the three-dimensional coordinates of the corresponding test points to obtain auxiliary straight lines;
s2, adjusting the positions of the standard workpieces to present the positions of other workpieces when placed;
and (5) acquiring the three-dimensional coordinates Q 'of the specific point on the adjusted standard workpiece again by using a standard instrument'jSolving for Q 'by rigid body transformation'jAnd QjA rotational translation matrix RT' in between;
the robot drives the single-line structured light sensor to obtain three-dimensional coordinates of each test point at different test positions according to a preset path, and the three-dimensional coordinates are recorded as measured data;
calculating a rotation translation matrix based on the three-dimensional coordinates of the test points recorded in the calibration process and the three-dimensional coordinate data of the test points in the measured data; on the basis, each auxiliary straight line in the standard data is subjected to rotational translation, and then the intersection points of the auxiliary straight line and the corresponding optical plane equation are recorded into a calibration point set;
taking the three-dimensional coordinates of each test point in the measured data and the distance between the intersection points in the corresponding calibration point set as a target function, and iterating by using an optimization method to obtain an optimal rotation translation matrix RT meeting the convergence condition;
s3, comparing the RT and the RT ', judging whether the difference value between the rotation component and the translation component between the RT and the RT' is smaller than a preset value, if so, the obtained optimal rotation and translation matrix RT meets the measurement requirement, and if not, the optimal rotation and translation matrix RT cannot meet the measurement requirement.
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