CN114993204A - Large-size component profile dynamic measurement and auxiliary feature positioning method and system - Google Patents
Large-size component profile dynamic measurement and auxiliary feature positioning method and system Download PDFInfo
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- G01B11/00—Measuring arrangements characterised by the use of optical techniques
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Abstract
The invention provides a method and a system for dynamically measuring a profile of a large-size component and positioning auxiliary features, wherein the method comprises the following steps: the device comprises a rotary table, a point cloud acquisition device, a three-axis holder, a cross laser and a large-size component; step S1: calibrating the relation among a coordinate system of the point cloud acquisition device, a three-axis holder coordinate system and a cross laser coordinate system; step S2: calibrating a pose transformation matrix of the large-size member at a plurality of preset positions; step S3: performing edge segmentation and noise point elimination on the global contour spliced according to the coordinate transformation matrix to obtain a background-free contour of a large-size member and obtain a virtual-real coordinate transformation matrix; step S4: and controlling the three-axis holder to enable the cross laser to project to the corresponding real member contour surface according to the local coordinate system of the feature to be processed in the CAD model, so as to realize automatic auxiliary feature positioning. The invention can overcome the problem of self-shielding of the profile of the workpiece and realize the integration of profile measurement and auxiliary feature positioning.
Description
Technical Field
The invention relates to the technical field of mechanical design, mechano-electronics, automatic control and visual measurement, in particular to a method and a system for dynamically measuring the profile of a large-size component and positioning auxiliary features.
Background
The large-size component processing and manufacturing, especially the characteristic processing on the complex component profile, needs to implement two preset steps: the first step is member profile measurement, and the second step is processing feature positioning, which essentially belongs to the problems of large-size profile measurement and feature positioning.
The main means at present is a large three-coordinate measuring and marking machine, which occupies a large area and has high investment cost. Non-contact measurement means such as a laser tracker often need multi-view measurement to overcome the problem of self shielding and the like, and need many times of visual calibration, and the measurement process is separated from the marking process, needs many times of auxiliary positioning.
The invention with the publication number of CN106338229B discloses a method for measuring the profile of a workpiece, which comprises placing the workpiece into a positioning cavity obtained by outward deviation of the designed outer profile line of the workpiece on a detection auxiliary fixture, positioning the workpiece by a corresponding positioning mechanism, forming corresponding detection points on the positioning cavity by each measurement point on the workpiece, positioning a vertical measuring rod capable of moving back and forth in a measuring device at the detection point of the detection auxiliary fixture, moving the measuring rod forward to abut against the measurement point of the workpiece, reading the difference between the actual moving distance of the measuring rod displayed by a scale of the detection auxiliary fixture and the theoretical deviation value of the detection point of the positioning cavity relative to the corresponding measurement point of the workpiece, namely the dimension deviation value of the workpiece at the measurement point, and further judging whether the gap between the workpiece and the adjacent workpiece meets the design requirements when the workpiece is installed.
Disclosure of Invention
Aiming at the defects in the prior art, the invention provides a method and a system for dynamically measuring the profile of a large-size component and positioning auxiliary features.
According to the method and the system for dynamically measuring the profile of the large-size component and positioning the auxiliary features, the scheme is as follows:
in a first aspect, a method for dynamically measuring a profile of a large-size component and positioning an auxiliary feature is provided, the method comprising: the device comprises a rotary table, a point cloud acquisition device, a three-axis holder, a cross laser and a large-size component;
the large-size component is fixed on the rotary table, the point cloud acquisition device acquires the local outline of a workpiece, and the cross laser is fixed at the tail end of the three-axis holder;
step S1: calibrating the relation among a coordinate system of the point cloud acquisition device, a coordinate system of a three-axis holder and a coordinate system of a cross laser;
step S2: calibrating a pose transformation matrix of a large-size member at a plurality of preset positions;
step S3: carrying out edge segmentation and noise point elimination related processing on the global contour spliced according to the coordinate transformation matrix to obtain a background-free contour of a large-size component, and carrying out virtual-real registration with a point cloud generated by a component CAD model to obtain a virtual-real coordinate transformation matrix;
step S4: and controlling the three-axis holder to enable the cross laser to project to the corresponding real member contour surface according to the local coordinate system of the feature to be processed in the CAD model, so as to realize automatic auxiliary feature positioning.
Preferably, the step S1 includes calibrating a transformation matrix from the cross laser coordinate system to the three-axis pan-tilt end coordinate system:
projecting the cross laser light spot on the calibration plate for multiple times, and enabling the projection optical axis to align with the grid intersection point of the calibration plate and the main line in the cross line to align with the grid line each time by controlling the pitching, yawing and overturning angles of the three-axis pan-tilt;
modeling a system composed of a three-axis holder and a cross laser, describing the posture of the cross laser according to the model and the rotation angle of the three-axis holder, establishing constraint according to the spot coordinates projected by the cross laser onto a calibration plate, and solving to obtain a transformation matrix from a cross laser coordinate system to a three-axis holder tail end coordinate system.
Preferably, the step S1 further includes calibrating a transformation matrix from the cross laser coordinate system to the three-axis pan-tilt end coordinate system:
adopting a calibration plate for calibration, and introducing three rotation amounts and three translations between a calibration plate coordinate system and a three-axis cloud platform base coordinate system:
the calibration plate is static, and when the three-axis cloud platform is rotated, the cross line of the cross laser passes through one grid line on the calibration plate; wherein, the optical axis of the cross line is aligned with the intersection point of the grid lines to obtain three constraint equations;
and adjusting the three-axis cloud platform, repeating for three times, wherein grid line intersection points of the three times are not overlapped, obtaining nine independent degree-of-freedom constraint equations, and solving to obtain three rotation amounts and three translation amounts between the calibration plate coordinate system and the three-axis cloud platform base coordinate system and between the cross laser coordinate system and the three-axis cloud platform base coordinate system.
Preferably, the step S1 further includes calibrating a transformation matrix from the point cloud acquisition device coordinate system to the three-axis cloud platform base coordinate system:
and solving a transformation matrix from the three-axis cloud platform base coordinate system to the calibration plate coordinate system according to the steps, solving the transformation matrix from the calibration plate coordinate system to the point cloud acquisition device coordinate system by adopting an iterative closest point algorithm, and multiplying the two matrixes to obtain the transformation matrix from the point cloud acquisition device coordinate system to the three-axis cloud platform base coordinate system.
Preferably, the step S4 includes:
step S4.1: converting the local coordinates of the features to be projected and positioned on the component coordinate system into a point cloud collection coordinate system through the virtual and real coordinate transformation matrix obtained in the step S3;
step S4.2: transforming the coordinates of the control points to be projected to the three-axis cloud platform base coordinate system through a coordinate transformation matrix from the point cloud acquisition device coordinate system to the three-axis cloud platform base coordinate system;
step S4.3: describing the posture of the cross laser according to a coordinate transformation matrix from a terminal coordinate system of the three-axis holder to a cross laser coordinate system and the pitch angle, the yaw angle and the roll angle of the three-axis holder, forming constraints with the coordinates of a control point to be projected, and establishing an equation set to solve to obtain the pitch angle, the yaw angle and the roll angle of the three-axis holder;
and controlling the three-axis holder-cross laser system to enable the cross laser to project to the profile surface of the corresponding real large-size component so as to complete feature positioning.
In a second aspect, a system for dynamically measuring the profile of a large-dimension member and positioning an auxiliary feature is provided, the system comprising: the device comprises a rotary table, a point cloud acquisition device, a three-axis holder, a cross laser and a large-size component;
the large-size component is fixed on the rotary table, the point cloud acquisition device acquires the local outline of a workpiece, and the cross laser is fixed at the tail end of the three-axis holder;
module M1: calibrating the relation among a coordinate system of the point cloud acquisition device, a coordinate system of a three-axis holder and a coordinate system of a cross laser;
module M2: calibrating a pose transformation matrix of the large-size member at a plurality of preset positions;
module M3: carrying out edge segmentation and noise point elimination related processing on the global contour spliced according to the coordinate transformation matrix to obtain a background-free contour of a large-size component, and carrying out virtual-real registration with point cloud generated by a component CAD model to obtain a virtual-real coordinate transformation matrix;
module M4: and controlling the three-axis holder to enable the cross laser to project to the corresponding real member contour surface according to the local coordinate system of the feature to be processed in the CAD model, so as to realize automatic auxiliary feature positioning.
Preferably, the module M1 includes a transformation matrix from the calibration cross laser coordinate system to the three-axis pan-tilt-head end coordinate system:
projecting the cross laser light spot on the calibration plate for multiple times, and enabling the projection optical axis to align with the grid intersection point of the calibration plate and the main line in the cross line to align with the grid line each time by controlling the pitching, yawing and overturning angles of the three-axis pan-tilt;
modeling a system composed of a three-axis holder and a cross laser, describing the posture of the cross laser according to the model and the rotation angle of the three-axis holder, establishing constraint according to the spot coordinates projected by the cross laser onto a calibration plate, and solving to obtain a transformation matrix from a cross laser coordinate system to a three-axis holder tail end coordinate system.
Preferably, the module M1 further includes a transformation matrix for calibrating the cross laser coordinate system to the three-axis pan-tilt-head end coordinate system:
adopting a calibration plate for calibration, and introducing three rotation amounts and three translations between a calibration plate coordinate system and a three-axis cloud platform base coordinate system:
the calibration plate is static, and when the three-axis cloud platform is rotated, the cross line of the cross laser passes through one grid line on the calibration plate; wherein, the optical axis of the cross line is aligned with the intersection point of the grid lines to obtain three constraint equations;
and adjusting the three-axis cloud platform, repeating for three times, wherein the intersection points of the grid lines of the three times are not overlapped to obtain nine independent degree-of-freedom constraint equations, and solving to obtain three rotation amounts and three translation amounts between the calibration plate coordinate system and the three-axis cloud platform base coordinate system and between the cross laser coordinate system and the three-axis cloud platform base coordinate system.
Preferably, the module M1 further includes a transformation matrix for calibrating the coordinate system of the point cloud acquisition device to the three-axis cloud platform base coordinate system:
and solving a transformation matrix from the three-axis cloud platform base coordinate system to the calibration plate coordinate system according to the steps, solving the transformation matrix from the calibration plate coordinate system to the point cloud acquisition device coordinate system by adopting an iterative closest point algorithm, and multiplying the two matrixes to obtain the transformation matrix from the point cloud acquisition device coordinate system to the three-axis cloud platform base coordinate system.
Preferably, said module M4 comprises:
module M4.1: converting the local coordinates of the features to be projected and positioned on the component coordinate system into a point cloud collection coordinate system through the virtual-real coordinate transformation matrix obtained by the module M3;
module M4.2: transforming the coordinates of the control points to be projected to the three-axis cloud platform base coordinate system through a coordinate transformation matrix from the point cloud acquisition device coordinate system to the three-axis cloud platform base coordinate system;
module M4.3: describing the posture of the cross laser according to a coordinate transformation matrix from a terminal coordinate system of the three-axis holder to a cross laser coordinate system and the pitch angle, the yaw angle and the roll angle of the three-axis holder, forming constraints with the coordinates of a control point to be projected, and establishing an equation set to solve to obtain the pitch angle, the yaw angle and the roll angle of the three-axis holder;
and controlling the three-axis holder-cross laser system to enable the cross laser to project to the profile surface of the corresponding real large-size component to complete feature positioning.
Compared with the prior art, the invention has the following beneficial effects:
the invention adopts multi-view dynamic profile measurement, overcomes the problem of self-shielding of the profile of a workpiece, improves the measurement precision through the preset position measurement with feedback, and simultaneously realizes the integration of profile measurement and auxiliary characteristic positioning by adopting a three-axis holder-cross laser system.
Drawings
Other features, objects and advantages of the invention will become more apparent upon reading of the detailed description of non-limiting embodiments with reference to the following drawings:
FIG. 1 is a schematic diagram of a system;
FIG. 2 is a cross laser line view;
FIG. 3 shows the cross laser line to grid alignment coordinate calibration.
Detailed Description
The present invention will be described in detail with reference to specific examples. The following examples will aid those skilled in the art in further understanding the present invention, but are not intended to limit the invention in any manner. It should be noted that it would be obvious to those skilled in the art that various changes and modifications can be made without departing from the spirit of the invention. All falling within the scope of the present invention.
The embodiment of the invention provides a method for dynamically measuring the outline of a large-size component and positioning auxiliary features, which is shown in figure 1 and comprises a rotary table, a point cloud acquisition device, a three-axis holder, a cross laser, the large-size component and the like, wherein the large-size component is a workpiece shown in figure 1. The three-axis holder comprises a high-precision servo motor, a control driver and the like, and a cross laser transmitter is fixed at the tail end of the three-axis holder.
The large-size component is fixed on the rotary table and synchronously rotates along with the rotary table according to the preset position, and the rotary table realizes the accurate positioning of the preset position through mechanical or electronic position feedback.
The point cloud acquisition device acquires the local contour of the large-size component, and multi-view dynamic global contour acquisition is realized through a plurality of rotary preset positions of the rotary table.
Referring to fig. 2 and 3, projected light spots of the cross laser are crossed lines of a cross-shaped horizontal line and a cross-shaped vertical line, and the cross-shaped horizontal line and the cross-shaped vertical line have asymmetric characteristics such as unequal length and non-central point of the crossed point, so as to distinguish the horizontal line from the vertical line and use one of the horizontal line and the vertical line as a main line.
And the cross laser is fixed at the tail end of the triaxial holder, and the triaxial holder projects a cross line in a cross shape to the surface of the profile of the large-size member by controlling a pitch angle, a yaw angle and a roll angle to form a local coordinate system mark of the feature to be processed.
And the local coordinate identification takes the cross point of the cross line as a coordinate origin and takes a main line in the cross line as a coordinate axis of the local coordinate system of the feature to be processed.
The method comprises the following specific steps:
step S1: and calibrating the relation among the coordinate system of the point cloud acquisition device, the coordinate system of the three-axis holder and the coordinate system of the cross laser.
Specifically, the steps include:
1) calibrating a transformation matrix from a laser coordinate system to a holder tail end coordinate system: projecting the cross laser light spot on the calibration plate for multiple times, and controlling the pitching, yawing and overturning angles of the three-axis pan-tilt head to enable the projection optical axis to align to the grid intersection point of the calibration plate and align to the main line in the cross line of the cross line to align to the grid line each time; modeling a system composed of a holder and laser, describing the posture of cross laser according to a model and a holder corner, establishing constraint according to spot coordinates projected by the cross laser onto a calibration plate, and solving to obtain a transformation matrix from a laser coordinate system to a holder tail end coordinate system.
2) The specific steps of calibrating the transformation matrix from the laser coordinate system to the cloud platform tail end coordinate system are as follows:
because the laser coordinate system and the cloud platform tail end coordinate system move synchronously, the laser coordinate system and the cloud platform tail end coordinate system do not rotate relatively, only translation exists, the rotation transformation between the cloud platform tail end coordinate system and the cloud platform base coordinate system (world coordinate system) is known, the transformation between the laser coordinate system and the cloud platform base coordinate system (world coordinate system) is only three unknown translation quantities, the calibration plate is adopted for calibration, and then three rotation quantities and three translations between the calibration plate coordinate system and the cloud platform base coordinate system are introduced.
The calibration plate is static, when the cloud platform is rotated, the cross-shaped laser lines pass through one grid line on the calibration plate, wherein the optical axis of the cross-shaped laser lines is aligned with the intersection point of the grid lines, and three constraint equations can be obtained. And adjusting the holder, repeating the three times (the intersection points of the grid lines are not overlapped for three times), obtaining nine independent degree-of-freedom constraint equations, and solving to obtain three rotation amounts and three translation amounts between the calibration plate coordinate system and the holder base coordinate system and three translation amounts between the laser coordinate system and the holder base coordinate system (the world coordinate system).
3) Calibrating a transformation matrix from a point cloud acquisition device coordinate system to a holder base coordinate system: and solving a transformation matrix from the cloud platform base coordinate system to the calibration plate coordinate system according to the steps, solving the transformation matrix from the calibration plate coordinate system to the point cloud acquisition device coordinate system by adopting an ICP (iterative closest point algorithm), and multiplying the two matrixes to obtain the transformation matrix from the point cloud acquisition device coordinate system to the cloud platform base coordinate system.
Step S2: calibrating a pose transformation matrix of the large-size member at a plurality of preset positions:
the visual calibration plate is fixed on the rotary worktable, the rotary table performs positioning and point cloud collection at a plurality of preset positions, the point cloud collection device obtains point clouds A1, A2, … and An, and intersection exists between the point clouds at the adjacent preset positions, such as A1, A2, A2 and A3.
Preferably, the preset positions may be indexed positions, such as 4 indexed (equal intervals of 90 °), 6 indexed (equal intervals of 60 °), etc., in order to ensure that there is a field intersection between adjacent preset positions.
And acquiring coordinate transformation matrixes among A1-A2, A2-A3, …, An-1-An and An-A1 by key point feature alignment, point cloud matching and methods such as singular value decomposition.
Step S3: and performing edge segmentation and noise point elimination related processing on the global contour spliced according to the coordinate transformation matrix to obtain a background-free contour of the large-size component, and performing virtual-real registration with point cloud generated by a component CAD model to obtain a virtual-real coordinate transformation matrix.
Step S4: and controlling the three-axis holder to enable the cross laser to project to the corresponding real member contour surface according to the local coordinate system of the feature to be processed in the CAD model, so as to realize automatic auxiliary feature positioning. The laser projection positioning method comprises the following specific steps:
step S4.1: and converting the local coordinates of the features to be projected and positioned on the component coordinate system into a point cloud collection coordinate system through the virtual and real coordinate transformation matrix obtained in the step S3. Three constraint equations are obtained by controlling the cross laser cross line to pass through the origin of the local coordinate system of the substitute processing characteristic, and the main shaft of the cross laser cross line is superposed with the coordinate axes of the local coordinate system, so that the pitch angle, the yaw angle and the roll angle of the holder are solved.
Step S4.2: and transforming the coordinates of the control points to be projected to the three-axis cloud platform base coordinate system through a coordinate transformation matrix from the point cloud acquisition device coordinate system to the three-axis cloud platform base coordinate system.
Step S4.3: according to a coordinate transformation matrix from a holder tail end coordinate system to a laser coordinate system and the pitch angle, the yaw angle and the roll angle of the holder, the cross laser attitude can be described, constraints are formed with the coordinates of a control point to be projected, and an equation set is established to solve to obtain the pitch angle, the yaw angle and the roll angle of the three-axis holder. And controlling the holder-laser system to enable the cross laser to be projected to the corresponding real member contour surface to complete feature positioning.
The embodiment of the invention provides a method and a system for dynamically measuring the profile of a large-size component and positioning auxiliary features, which adopt multi-view dynamic profile measurement, overcome the problem of self-shielding of the profile of a workpiece, improve the measurement precision through preset position measurement with feedback, and realize the integration of profile measurement and auxiliary feature positioning by adopting a holder-cross laser system.
Those skilled in the art will appreciate that, in addition to implementing the system and its various devices, modules, units provided by the present invention as pure computer readable program code, the system and its various devices, modules, units provided by the present invention can be fully implemented by logically programming method steps in the form of logic gates, switches, application specific integrated circuits, programmable logic controllers, embedded microcontrollers and the like. Therefore, the system and various devices, modules and units thereof provided by the invention can be regarded as a hardware component, and the devices, modules and units included in the system for realizing various functions can also be regarded as structures in the hardware component; means, modules, units for performing the various functions may also be regarded as structures within both software modules and hardware components for performing the method.
The foregoing description of specific embodiments of the present invention has been presented. It is to be understood that the present invention is not limited to the specific embodiments described above, and that various changes or modifications may be made by one skilled in the art within the scope of the appended claims without departing from the spirit of the invention. The embodiments and features of the embodiments of the present application may be combined with each other arbitrarily without conflict.
Claims (10)
1. A method for dynamically measuring the profile of a large-size component and positioning auxiliary features is characterized by comprising the following steps: the device comprises a rotary table, a point cloud acquisition device, a three-axis holder, a cross laser and a large-size component;
the large-size component is fixed on the rotary table, the point cloud acquisition device acquires the local outline of a workpiece, and the cross laser is fixed at the tail end of the three-axis holder;
step S1: calibrating the relation among a coordinate system of the point cloud acquisition device, a coordinate system of a three-axis holder and a coordinate system of a cross laser;
step S2: calibrating a pose transformation matrix of the large-size member at a plurality of preset positions;
step S3: carrying out edge segmentation and noise point elimination related processing on the global contour spliced according to the coordinate transformation matrix to obtain a background-free contour of a large-size component, and carrying out virtual-real registration with point cloud generated by a component CAD model to obtain a virtual-real coordinate transformation matrix;
step S4: and controlling the three-axis holder to enable the cross laser to project to the corresponding real member contour surface according to the local coordinate system of the feature to be processed in the CAD model, so as to realize automatic auxiliary feature positioning.
2. The method for dynamically measuring the profile of a large-dimension member and locating an auxiliary feature according to claim 1, wherein the step S1 includes calibrating a transformation matrix from a cross laser coordinate system to a three-axis pan-tilt end coordinate system:
projecting the cross laser light spot on the calibration plate for multiple times, and enabling the projection optical axis to align with the grid intersection point of the calibration plate and the main line in the cross line to align with the grid line each time by controlling the pitching, yawing and overturning angles of the three-axis pan-tilt;
modeling a system composed of a three-axis holder and a cross laser, describing the posture of the cross laser according to the model and the rotation angle of the three-axis holder, establishing constraint according to the spot coordinates projected by the cross laser onto a calibration plate, and solving to obtain a transformation matrix from a cross laser coordinate system to a three-axis holder tail end coordinate system.
3. The method for dynamically measuring the profile of a large-dimension member and positioning an auxiliary feature according to claim 2, wherein the step S1 further comprises calibrating a transformation matrix from the cross laser coordinate system to the three-axis pan-tilt-head end coordinate system:
adopting a calibration plate for calibration, and introducing three rotation amounts and three translations between a coordinate system of the calibration plate and a base coordinate system of the three-axis cloud platform:
the calibration plate is static, and when the three-axis cloud platform is rotated, the cross line of the cross laser passes through one grid line on the calibration plate; wherein, the optical axis of the cross line is aligned with the intersection point of the grid lines to obtain three constraint equations;
and adjusting the three-axis cloud platform, repeating for three times, wherein grid line intersection points of the three times are not overlapped, obtaining nine independent degree-of-freedom constraint equations, and solving to obtain three rotation amounts and three translation amounts between the calibration plate coordinate system and the three-axis cloud platform base coordinate system and between the cross laser coordinate system and the three-axis cloud platform base coordinate system.
4. The method for dynamically measuring the profile of a large-size member and locating an assistant feature of claim 3, wherein the step S1 further comprises calibrating a transformation matrix from a point cloud acquisition device coordinate system to a three-axis cloud platform base coordinate system:
and solving a transformation matrix from the three-axis cloud platform base coordinate system to the calibration plate coordinate system according to the steps, solving the transformation matrix from the calibration plate coordinate system to the point cloud acquisition device coordinate system by adopting an iterative closest point algorithm, and multiplying the two matrixes to obtain the transformation matrix from the point cloud acquisition device coordinate system to the three-axis cloud platform base coordinate system.
5. The method for dynamically measuring the profile of a large-dimension member and positioning an auxiliary feature of claim 1, wherein the step S4 comprises:
step S4.1: converting the local coordinates of the features to be projected and positioned on the component coordinate system into a point cloud collection coordinate system through the virtual and real coordinate transformation matrix obtained in the step S3;
step S4.2: transforming the coordinates of the control points to be projected to the three-axis cloud platform base coordinate system through a coordinate transformation matrix from the point cloud acquisition device coordinate system to the three-axis cloud platform base coordinate system;
step S4.3: describing the posture of the cross laser according to a coordinate transformation matrix from a terminal coordinate system of the three-axis holder to a cross laser coordinate system and the pitch angle, the yaw angle and the roll angle of the three-axis holder, forming constraints with the coordinates of a control point to be projected, and establishing an equation set to solve to obtain the pitch angle, the yaw angle and the roll angle of the three-axis holder;
and controlling the three-axis holder-cross laser system to enable the cross laser to project to the profile surface of the corresponding real large-size component so as to complete feature positioning.
6. A system for dynamically measuring the profile of a large-dimension member and locating an auxiliary feature, comprising: the device comprises a rotary table, a point cloud acquisition device, a three-axis holder, a cross laser and a large-size component;
the large-size component is fixed on the rotary table, the point cloud acquisition device acquires the local outline of a workpiece, and the cross laser is fixed at the tail end of the three-axis holder;
module M1: calibrating the relation among a coordinate system of the point cloud acquisition device, a coordinate system of a three-axis holder and a coordinate system of a cross laser;
module M2: calibrating a pose transformation matrix of a large-size member at a plurality of preset positions;
module M3: carrying out edge segmentation and noise point elimination related processing on the global contour spliced according to the coordinate transformation matrix to obtain a background-free contour of a large-size component, and carrying out virtual-real registration with point cloud generated by a component CAD model to obtain a virtual-real coordinate transformation matrix;
module M4: and controlling the three-axis holder to enable the cross laser to project to the corresponding real component contour surface according to the local coordinate system of the feature to be processed in the CAD model, so as to realize automatic auxiliary feature positioning.
7. The system for dynamically measuring the profile of a large-scale member and locating an auxiliary feature of claim 6, wherein the module M1 comprises a transformation matrix from a calibration cross laser coordinate system to a three-axis pan-tilt-head end coordinate system:
projecting the cross laser light spot on the calibration plate for multiple times, and enabling the projection optical axis to align with the grid intersection point of the calibration plate and the main line in the cross line to align with the grid line each time by controlling the pitching, yawing and overturning angles of the three-axis pan-tilt;
modeling a system composed of a three-axis holder and a cross laser, describing the posture of the cross laser according to the model and the rotation angle of the three-axis holder, establishing constraint according to the spot coordinates projected by the cross laser onto a calibration plate, and solving to obtain a transformation matrix from a cross laser coordinate system to a three-axis holder tail end coordinate system.
8. The system for dynamically measuring the profile of a large-scale member and locating an auxiliary feature of claim 7, wherein the module M1 further comprises a transformation matrix for calibrating the cross laser coordinate system to the three-axis pan-tilt-head end coordinate system:
adopting a calibration plate for calibration, and introducing three rotation amounts and three translations between a calibration plate coordinate system and a three-axis cloud platform base coordinate system:
the calibration plate is static, and when the three-axis cloud platform is rotated, the cross line of the cross laser passes through one grid line on the calibration plate; wherein, the optical axis of the cross line is aligned with the intersection point of the grid lines to obtain three constraint equations;
and adjusting the three-axis cloud platform, repeating for three times, wherein grid line intersection points of the three times are not overlapped, obtaining nine independent degree-of-freedom constraint equations, and solving to obtain three rotation amounts and three translation amounts between the calibration plate coordinate system and the three-axis cloud platform base coordinate system and between the cross laser coordinate system and the three-axis cloud platform base coordinate system.
9. The system for dynamically measuring the profile of a large-scale member and locating an auxiliary feature of claim 8, wherein the module M1 further comprises a transformation matrix for calibrating the coordinate system of the point cloud acquisition device to the base coordinate system of the three-axis cloud platform:
and solving a transformation matrix from the three-axis cloud platform base coordinate system to the calibration plate coordinate system according to the steps, solving the transformation matrix from the calibration plate coordinate system to the point cloud acquisition device coordinate system by adopting an iterative closest point algorithm, and multiplying the two matrixes to obtain the transformation matrix from the point cloud acquisition device coordinate system to the three-axis cloud platform base coordinate system.
10. The system for dynamically measuring the profile of a large-scale member and locating an assist feature as set forth in claim 6, wherein the module M4 comprises:
module M4.1: converting the local coordinates of the features to be projected and positioned on the component coordinate system into a point cloud collection coordinate system through the virtual-real coordinate transformation matrix obtained by the module M3;
module M4.2: transforming the coordinates of the control points to be projected to the three-axis cloud platform base coordinate system through a coordinate transformation matrix from the point cloud acquisition device coordinate system to the three-axis cloud platform base coordinate system;
module M4.3: describing the posture of the cross laser according to a coordinate transformation matrix from a terminal coordinate system of the three-axis holder to a cross laser coordinate system and the pitch angle, the yaw angle and the roll angle of the three-axis holder, forming constraints with the coordinates of a control point to be projected, and establishing an equation set to solve to obtain the pitch angle, the yaw angle and the roll angle of the three-axis holder;
and controlling the three-axis holder-cross laser system to enable the cross laser to project to the profile surface of the corresponding real large-size component so as to complete feature positioning.
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Citations (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5430547A (en) * | 1992-04-07 | 1995-07-04 | Honda Giken Kogyo Kabushiki Kaisha | Non-contacting position detecting apparatus |
| CN103913117A (en) * | 2014-03-26 | 2014-07-09 | 上海数联空间科技有限公司 | Three-dimensional laser scanner positioning device and laser point cloud absolute positioning method |
| CN105737762A (en) * | 2016-05-09 | 2016-07-06 | 中国民用航空飞行学院 | Aviation engine blade profile measuring method |
| CN106017433A (en) * | 2016-05-27 | 2016-10-12 | 北京环境特性研究所 | Three-dimensional posture positioning method and system in anechoic chamber |
| CN106767401A (en) * | 2016-11-26 | 2017-05-31 | 江苏瑞伯特视觉科技股份有限公司 | A kind of shaft hole series part based on cross laser and machine vision determines appearance localization method |
| CN107560594A (en) * | 2016-06-30 | 2018-01-09 | 莱卡地球系统公开股份有限公司 | Surveying device including altitude measurement system and the method for measuring height |
| CN109613546A (en) * | 2018-11-10 | 2019-04-12 | 浙江大学 | Converter furnace chamber method for three-dimensional measurement and measuring device based on three-dimensional laser radar auxiliary positioning |
| CN112325796A (en) * | 2020-10-26 | 2021-02-05 | 上海交通大学 | Large-scale workpiece profile measuring method based on auxiliary positioning multi-view point cloud splicing |
-
2022
- 2022-06-07 CN CN202210636112.0A patent/CN114993204B/en active Active
Patent Citations (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5430547A (en) * | 1992-04-07 | 1995-07-04 | Honda Giken Kogyo Kabushiki Kaisha | Non-contacting position detecting apparatus |
| CN103913117A (en) * | 2014-03-26 | 2014-07-09 | 上海数联空间科技有限公司 | Three-dimensional laser scanner positioning device and laser point cloud absolute positioning method |
| CN105737762A (en) * | 2016-05-09 | 2016-07-06 | 中国民用航空飞行学院 | Aviation engine blade profile measuring method |
| CN106017433A (en) * | 2016-05-27 | 2016-10-12 | 北京环境特性研究所 | Three-dimensional posture positioning method and system in anechoic chamber |
| CN107560594A (en) * | 2016-06-30 | 2018-01-09 | 莱卡地球系统公开股份有限公司 | Surveying device including altitude measurement system and the method for measuring height |
| CN106767401A (en) * | 2016-11-26 | 2017-05-31 | 江苏瑞伯特视觉科技股份有限公司 | A kind of shaft hole series part based on cross laser and machine vision determines appearance localization method |
| CN109613546A (en) * | 2018-11-10 | 2019-04-12 | 浙江大学 | Converter furnace chamber method for three-dimensional measurement and measuring device based on three-dimensional laser radar auxiliary positioning |
| CN112325796A (en) * | 2020-10-26 | 2021-02-05 | 上海交通大学 | Large-scale workpiece profile measuring method based on auxiliary positioning multi-view point cloud splicing |
Non-Patent Citations (2)
| Title |
|---|
| XUNJIN WU: "Domain Adaptation for Viewpoint Estimation with Image Generation", 《2021 INTERNATIONAL CONFERENCE ON CONTROL, AUTOMATION AND INFORMATION SCIENCES (ICCAIS)》 * |
| 李彬鹏: "大尺寸飞机零部件检测技术研究进展", 《上海工程技术大学学报》 * |
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