CN111882614A - KNN-ICP algorithm-based free-form surface positioning method - Google Patents
KNN-ICP algorithm-based free-form surface positioning method Download PDFInfo
- Publication number
- CN111882614A CN111882614A CN202010748896.7A CN202010748896A CN111882614A CN 111882614 A CN111882614 A CN 111882614A CN 202010748896 A CN202010748896 A CN 202010748896A CN 111882614 A CN111882614 A CN 111882614A
- Authority
- CN
- China
- Prior art keywords
- point cloud
- matrix
- knn
- robot
- form surface
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
Images
Classifications
-
- G—PHYSICS
- G06—COMPUTING; CALCULATING OR COUNTING
- G06T—IMAGE DATA PROCESSING OR GENERATION, IN GENERAL
- G06T7/00—Image analysis
- G06T7/70—Determining position or orientation of objects or cameras
- G06T7/73—Determining position or orientation of objects or cameras using feature-based methods
-
- G—PHYSICS
- G06—COMPUTING; CALCULATING OR COUNTING
- G06F—ELECTRIC DIGITAL DATA PROCESSING
- G06F17/00—Digital computing or data processing equipment or methods, specially adapted for specific functions
- G06F17/10—Complex mathematical operations
- G06F17/16—Matrix or vector computation, e.g. matrix-matrix or matrix-vector multiplication, matrix factorization
-
- G—PHYSICS
- G06—COMPUTING; CALCULATING OR COUNTING
- G06F—ELECTRIC DIGITAL DATA PROCESSING
- G06F30/00—Computer-aided design [CAD]
- G06F30/20—Design optimisation, verification or simulation
-
- G—PHYSICS
- G06—COMPUTING; CALCULATING OR COUNTING
- G06N—COMPUTING ARRANGEMENTS BASED ON SPECIFIC COMPUTATIONAL MODELS
- G06N3/00—Computing arrangements based on biological models
- G06N3/02—Neural networks
- G06N3/04—Architecture, e.g. interconnection topology
- G06N3/045—Combinations of networks
-
- G—PHYSICS
- G06—COMPUTING; CALCULATING OR COUNTING
- G06T—IMAGE DATA PROCESSING OR GENERATION, IN GENERAL
- G06T2207/00—Indexing scheme for image analysis or image enhancement
- G06T2207/10—Image acquisition modality
- G06T2207/10028—Range image; Depth image; 3D point clouds
Landscapes
- Engineering & Computer Science (AREA)
- Physics & Mathematics (AREA)
- Theoretical Computer Science (AREA)
- General Physics & Mathematics (AREA)
- Mathematical Physics (AREA)
- Data Mining & Analysis (AREA)
- General Engineering & Computer Science (AREA)
- Pure & Applied Mathematics (AREA)
- Software Systems (AREA)
- Evolutionary Computation (AREA)
- Mathematical Optimization (AREA)
- Mathematical Analysis (AREA)
- Computing Systems (AREA)
- Computational Mathematics (AREA)
- Biophysics (AREA)
- Health & Medical Sciences (AREA)
- Biomedical Technology (AREA)
- Life Sciences & Earth Sciences (AREA)
- Computational Linguistics (AREA)
- Molecular Biology (AREA)
- General Health & Medical Sciences (AREA)
- Artificial Intelligence (AREA)
- Algebra (AREA)
- Databases & Information Systems (AREA)
- Computer Hardware Design (AREA)
- Geometry (AREA)
- Computer Vision & Pattern Recognition (AREA)
- Numerical Control (AREA)
Abstract
The invention discloses a KNN-ICP algorithm-based free-form surface positioning method, which comprises the following steps: (1) using a robot to perform point collection on the curved surface to obtain actual measurement point cloud data; (2) dispersing the CAD model of the curved surface according to the machining tolerance to generate theoretical point cloud data; (3) calculating the closest point and the minimum distance of each data point in the actual measurement point cloud in the theoretical point cloud by using a KNN algorithm; judging whether an iteration termination condition is met, if so, turning to the step (5), and if not, turning to the step (4); (4) calculating a rotation matrix and a translation matrix by using a quaternion method to enable the current measurement point set to approach the nearest point set, obtaining the position of new measurement point cloud data, and returning to the step (3); (5) the iteration is terminated and the object coordinate system of the object relative to the robot is output. The free-form surface positioning method provided by the invention searches the closest point through the KNN algorithm, is simple to realize and has high calculation efficiency.
Description
Technical Field
The invention belongs to the technical field of computer-aided manufacturing and robot machining, and particularly relates to a KNN-ICP algorithm-based free-form surface positioning method.
Background
Off-line programmed robot polishing is the most suitable robot polishing mode at present. The specific idea is that the working conditions around the robot are simulated on a computer through software, in a virtual three-dimensional working condition, the motion trail of the robot is directly generated in the computer according to the operation of an operator on the basis of the matching of the materials, the size and the shape of a machined part, a corresponding program is generated, and the program is led into a robot system to operate.
During robot grinding, the positioning of the workpiece coordinate system (establishing the coordinate system of the workpiece relative to the robot) is very important. The workpiece self-positioning means that a computer and a sensor measuring system are utilized, and accurate positioning of the workpiece under actual working conditions is realized through a pose solving algorithm, and the essence of the workpiece self-positioning means that accurate registration of three-dimensional point cloud is realized. In recent years, researchers at home and abroad develop systematic research around the three-dimensional Point cloud matching problem, the most representative of which is the iterative closest Point algorithm (ICP) proposed by Besl and McKay, and the algorithm is simple to implement, high in precision and low in calculation efficiency.
Disclosure of Invention
Aiming at the defects or improvement requirements of the prior art, in order to more efficiently and accurately establish a workpiece coordinate system of a workpiece relative to a robot, the invention adopts a robot system to obtain actual measurement point cloud data of the whole curved surface and provides a KNN-ICP algorithm-based free-form surface positioning method; the method is simple to implement and high in calculation efficiency, and the workpiece coordinate system can be accurately calculated.
The invention is realized by the following technical scheme:
a KNN-ICP algorithm-based free-form surface positioning method is characterized by comprising the following steps:
(1) using a robot to perform point collection on the curved surface to obtain actual measurement point cloud data;
(2) CAD of curved surfaces based on machining tolerancesThe model is dispersed to generate theoretical target point cloud data;
(3) Calculating actual measurement point cloud by using KNN algorithmEach data point inClosest point of (3)And corresponding shortest distanceWhereinIndicating number of iterations, initial case,(ii) a Is provided withFor a given iteration end precision, ifIf yes, turning to the step (5), otherwise, turning to the step (4);
(4) calculating a rotation matrix by using a quaternion methodAnd translation matrixObtaining new measuring point cloud position=,So that the current measurement point cloudApproximationAnd returning to the step (3);
(5) the iteration is terminated and the object coordinate system of the object relative to the robot is output.
In step (1), the robot collects points of the free-form surface, and the number of point cloud data obtained is further optimizedAnd is and。
in the further optimization of the technical scheme of the invention, a quaternion method is adopted in the step (4) to calculate the rotation matrixAnd translation matrixSuppose that the actual measurement point set and the theoretical target point set are respectivelyAndthe rotation matrix isThe translation matrix isThe specific calculation steps are as follows:
(4.2) calculating a covariance matrix according to the centralized data point setAnd constructing a positive definite matrix through the covariance matrix:
(4.3) calculating the eigenvalue of the positive definite matrix N, wherein the eigenvector corresponding to the maximum eigenvalue corresponds to the rotation quaternion as follows:
Compared with the prior art, the invention has the following beneficial effects: the free-form surface positioning method searches the closest point through a KNN algorithm, is simple to implement and has high calculation efficiency.
Drawings
Fig. 1 is a general flowchart of a KNN-ICP algorithm based free-form surface localization method.
Detailed Description
In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention will be described in further detail with reference to fig. 1 and an embodiment. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention. In addition, the technical features involved in the embodiments of the present invention described below may be combined with each other as long as they do not conflict with each other.
As shown in fig. 1, a method for locating a free-form surface based on a KNN-ICP algorithm includes the following steps:
(1) using a robot to align curved surfacesSampling points to obtain actual measurement point cloud data;
(2) Dispersing the CAD model of the curved surface according to the processing tolerance to generate theoretical target point cloud data;
(3) Calculating actual measurement point cloud by using KNN algorithmEach data point inClosest point of (3)And corresponding shortest distanceWhereinIndicating number of iterations, initial case,(ii) a Is provided withFor a given iteration end precision, ifIf yes, turning to the step (5), otherwise, turning to the step (4);
(4) calculating a rotation matrix by using a quaternion methodAnd translation matrixObtaining new measuring point cloud position=,So that the current measurement point cloudApproximationAnd returning to the step (3);
(5) the iteration is terminated and the object coordinate system of the object relative to the robot is output.
In this embodiment, in step (1), the robot performs point acquisition on the free-form surface, and the number of point cloud data obtained isAnd is and。
in this embodiment, in step (4), a quaternion method is used to calculate the rotation matrixAnd translation matrixSuppose that the actual measurement point set and the theoretical target point set are respectivelyAndthe rotation matrix isThe translation matrix isThe specific calculation steps are as follows:
(4.2) calculating a covariance matrix according to the centralized data point setAnd constructing a positive definite matrix through the covariance matrix:
(4.3) calculating the eigenvalue of the positive definite matrix N, wherein the eigenvector corresponding to the maximum eigenvalue corresponds to the rotation quaternion as follows:
Example 1
Off-line programmed robot polishing is the most suitable robot polishing mode at present. The specific idea is that the working conditions around the robot are simulated on a computer through software, the motion trail of the robot is directly generated inside the computer in the virtual three-dimensional working conditions, and a corresponding program is generated and is led into a robot system for engineering operation.
The embodiment further describes the method of the present embodiment by taking the robot off-line programming hub grinding as an example.
The specification of the present embodiment is (550 mm)550mm250 mm) of a wheel hub CAD model. In the robot off-line programming polishing scheme, a robot is utilized to collect points on a curved surface to obtain actual measurement point cloud data(ii) a Dispersing the CAD model of the curved surface according to the processing tolerance to generate theoretical point cloud data(ii) a In the embodiment, actual measurement point cloud data (12 points) are obtained, and theoretically, the more the actual measurement point cloud data is, the more accurate the calculation is; and (4) dispersing into theoretical point cloud data (2303316).
Given iteration termination accuracy in this embodiment0.01mm, algorithm run time: 15.4288s, the calculated attitude transformation matrix is:
it will be understood by those skilled in the art that the foregoing is only a preferred embodiment of the present invention, and is not intended to limit the invention, and that any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the scope of the present invention.
Claims (3)
1. A KNN-ICP algorithm-based free-form surface positioning method is characterized by comprising the following steps:
(1) using a robot to perform point collection on the curved surface to obtain actual measurement point cloud data;
(2) Dispersing the CAD model of the curved surface according to the processing tolerance to generate theoretical target point cloud data;
(3) Calculating actual measurement point cloud by using KNN algorithmEach data point inClosest point of (3)And corresponding shortest distanceWhereinIndicating number of iterations, initial case,(ii) a Is provided withFor a given iteration end precision, ifIf yes, turning to the step (5), otherwise, turning to the step (4);
(4) using quaternion method to calculate rotationRotating matrixAnd translation matrixObtaining new measuring point cloud position=,So that the current measurement point cloudApproximationAnd returning to the step (3);
(5) the iteration is terminated and the object coordinate system of the object relative to the robot is output.
3. the KNN-ICP algorithm-based free-form surface positioning method according to claim 1, wherein a quaternion method is adopted in the step (4) to calculate the rotation matrixAnd translation matrixSuppose that the actual measurement point set and the theoretical target point set are respectivelyAndthe rotation matrix isThe translation matrix isThe specific calculation steps are as follows:
(4.2) calculating a covariance matrix according to the centralized data point setAnd constructing a positive definite matrix through the covariance matrix:
(4.3) calculating the eigenvalue of the positive definite matrix N, wherein the eigenvector corresponding to the maximum eigenvalue corresponds to the rotation quaternion as follows:
Priority Applications (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
CN202010748896.7A CN111882614A (en) | 2020-07-30 | 2020-07-30 | KNN-ICP algorithm-based free-form surface positioning method |
PCT/CN2020/108784 WO2022021479A1 (en) | 2020-07-30 | 2020-08-13 | Freeform surface positioning method based on knn-icp algorithm |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
CN202010748896.7A CN111882614A (en) | 2020-07-30 | 2020-07-30 | KNN-ICP algorithm-based free-form surface positioning method |
Publications (1)
Publication Number | Publication Date |
---|---|
CN111882614A true CN111882614A (en) | 2020-11-03 |
Family
ID=73204247
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
CN202010748896.7A Pending CN111882614A (en) | 2020-07-30 | 2020-07-30 | KNN-ICP algorithm-based free-form surface positioning method |
Country Status (2)
Country | Link |
---|---|
CN (1) | CN111882614A (en) |
WO (1) | WO2022021479A1 (en) |
Families Citing this family (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN114972448B (en) * | 2022-05-26 | 2024-07-16 | 合肥工业大学 | ICP algorithm-based reduced-dimension acceleration point cloud registration method |
CN116991117B (en) * | 2023-09-25 | 2024-01-05 | 南京航空航天大学 | Rapid programming method for personalized part machining |
CN118036899B (en) * | 2024-04-10 | 2024-06-14 | 山东亿昌装配式建筑科技有限公司 | Building decoration intelligent management system based on BIM |
Citations (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
KR20010028247A (en) * | 1999-09-20 | 2001-04-06 | 유범상 | Automatic control method for mold-polishing robot |
CN103955939A (en) * | 2014-05-16 | 2014-07-30 | 重庆理工大学 | Boundary feature point registering method for point cloud splicing in three-dimensional scanning system |
CN104484508A (en) * | 2014-11-26 | 2015-04-01 | 华中科技大学 | Optimizing method for noncontact three-dimensional matching detection of complex curved-surface part |
CN104680530A (en) * | 2015-03-01 | 2015-06-03 | 江西科技学院 | ICP algorithm |
-
2020
- 2020-07-30 CN CN202010748896.7A patent/CN111882614A/en active Pending
- 2020-08-13 WO PCT/CN2020/108784 patent/WO2022021479A1/en active Application Filing
Patent Citations (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
KR20010028247A (en) * | 1999-09-20 | 2001-04-06 | 유범상 | Automatic control method for mold-polishing robot |
CN103955939A (en) * | 2014-05-16 | 2014-07-30 | 重庆理工大学 | Boundary feature point registering method for point cloud splicing in three-dimensional scanning system |
CN104484508A (en) * | 2014-11-26 | 2015-04-01 | 华中科技大学 | Optimizing method for noncontact three-dimensional matching detection of complex curved-surface part |
CN104680530A (en) * | 2015-03-01 | 2015-06-03 | 江西科技学院 | ICP algorithm |
Non-Patent Citations (1)
Title |
---|
夏永刚: "利用三维激光扫描数据和KNNs-ICP算法进行变形分析", 《江西科学》 * |
Also Published As
Publication number | Publication date |
---|---|
WO2022021479A1 (en) | 2022-02-03 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
CN111882614A (en) | KNN-ICP algorithm-based free-form surface positioning method | |
CN112284290B (en) | Autonomous measurement method and system for aero-engine blade robot | |
CN109883443B (en) | Line structure optical sensor spatial attitude calibration method | |
CN109163675B (en) | Method for detecting angular pendulum shaft position accuracy based on laser tracker | |
Li et al. | Interference-free inspection path generation for impeller blades using an on-machine probe | |
CN102183205A (en) | Method for matching optimal assembly poses of large-sized parts | |
CN114055255B (en) | Large-scale complex component surface polishing path planning method based on real-time point cloud | |
CN113421291B (en) | Workpiece position alignment method using point cloud registration technology and three-dimensional reconstruction technology | |
CN109323665B (en) | Precise three-dimensional measurement method for line-structured light-driven holographic interference | |
CN113486470B (en) | Assembly body pose calculation method considering non-ideal surface contact state | |
CN110103071B (en) | Digital locating machining method for deformed complex part | |
Liu et al. | High precision calibration for three-dimensional vision-guided robot system | |
CN108508848A (en) | A kind of appraisal procedure of the Milling Process profile errors based on interpolation data | |
CN106568365B (en) | A kind of detection of sphere hole system complex position degree error and assessment method | |
CN109343468A (en) | A kind of blade multiaxis orbit generation method based on projection biasing | |
CN115937468A (en) | Automatic generation method for machining program of countless-module robot | |
Wang et al. | Fast forward kinematics algorithm for real-time and high-precision control of the 3-RPS parallel mechanism | |
Xie et al. | Pose error estimation using a cylinder in scanner-based robotic belt grinding | |
CN113799130B (en) | Robot pose calibration method in man-machine cooperation assembly | |
CN109773593B (en) | Grinding method based on allowance constraint condition | |
CN112936274B (en) | Robot-clamped flexible grinding wheel pose identification method | |
CN112784364A (en) | Method for calculating machining allowance of aircraft wing body joint | |
CN116587268B (en) | Milling precision improving method for large-area robot in space | |
Zhang et al. | Robot automation grinding process for nuclear reactor coolant pump based on reverse engineering | |
CN114131605B (en) | Automatic registration adjustment device and method for ship part polishing track |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
PB01 | Publication | ||
PB01 | Publication | ||
SE01 | Entry into force of request for substantive examination | ||
SE01 | Entry into force of request for substantive examination | ||
RJ01 | Rejection of invention patent application after publication |
Application publication date: 20201103 |
|
RJ01 | Rejection of invention patent application after publication |