CN111739166A - Simplifying method applied to three-dimensional model of transmission line hardware - Google Patents
Simplifying method applied to three-dimensional model of transmission line hardware Download PDFInfo
- Publication number
- CN111739166A CN111739166A CN202010446175.0A CN202010446175A CN111739166A CN 111739166 A CN111739166 A CN 111739166A CN 202010446175 A CN202010446175 A CN 202010446175A CN 111739166 A CN111739166 A CN 111739166A
- Authority
- CN
- China
- Prior art keywords
- boundary
- dimensional model
- edge
- transmission line
- power transmission
- 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
- 238000000034 method Methods 0.000 title claims abstract description 32
- 230000005540 biological transmission Effects 0.000 title claims abstract description 22
- 239000011159 matrix material Substances 0.000 claims description 4
- 239000013598 vector Substances 0.000 claims description 4
- 238000004364 calculation method Methods 0.000 claims description 2
- 239000000203 mixture Substances 0.000 claims 1
- 239000002994 raw material Substances 0.000 claims 1
- 238000013461 design Methods 0.000 abstract description 5
- 230000000007 visual effect Effects 0.000 abstract description 2
- 238000012423 maintenance Methods 0.000 description 4
- 238000012545 processing Methods 0.000 description 4
- 238000012986 modification Methods 0.000 description 2
- 230000004048 modification Effects 0.000 description 2
- 238000011160 research Methods 0.000 description 2
- 238000003860 storage Methods 0.000 description 2
- 230000009286 beneficial effect Effects 0.000 description 1
- 238000012217 deletion Methods 0.000 description 1
- 230000037430 deletion Effects 0.000 description 1
- 238000011161 development Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 239000012212 insulator Substances 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 238000013507 mapping Methods 0.000 description 1
- 238000005457 optimization Methods 0.000 description 1
Classifications
-
- G—PHYSICS
- G06—COMPUTING; CALCULATING OR COUNTING
- G06T—IMAGE DATA PROCESSING OR GENERATION, IN GENERAL
- G06T17/00—Three dimensional [3D] modelling, e.g. data description of 3D objects
- G06T17/20—Finite element generation, e.g. wire-frame surface description, tesselation
-
- G—PHYSICS
- G06—COMPUTING; CALCULATING OR COUNTING
- G06F—ELECTRIC DIGITAL DATA PROCESSING
- G06F18/00—Pattern recognition
- G06F18/20—Analysing
- G06F18/23—Clustering techniques
-
- G—PHYSICS
- G06—COMPUTING; CALCULATING OR COUNTING
- G06T—IMAGE DATA PROCESSING OR GENERATION, IN GENERAL
- G06T17/00—Three dimensional [3D] modelling, e.g. data description of 3D objects
- G06T17/30—Polynomial surface description
Landscapes
- Engineering & Computer Science (AREA)
- Physics & Mathematics (AREA)
- Theoretical Computer Science (AREA)
- General Physics & Mathematics (AREA)
- Data Mining & Analysis (AREA)
- Software Systems (AREA)
- Geometry (AREA)
- Computer Graphics (AREA)
- Bioinformatics & Computational Biology (AREA)
- Life Sciences & Earth Sciences (AREA)
- General Engineering & Computer Science (AREA)
- Evolutionary Biology (AREA)
- Computer Vision & Pattern Recognition (AREA)
- Bioinformatics & Cheminformatics (AREA)
- Artificial Intelligence (AREA)
- Evolutionary Computation (AREA)
- Algebra (AREA)
- Mathematical Analysis (AREA)
- Mathematical Optimization (AREA)
- Mathematical Physics (AREA)
- Pure & Applied Mathematics (AREA)
- Information Retrieval, Db Structures And Fs Structures Therefor (AREA)
Abstract
The invention discloses a simplifying method applied to a three-dimensional model of a power transmission line hardware fitting, which relates to the technical field of three-dimensional design of power transmission lines and comprises the following steps: the method comprises the following steps: carrying out boundary edge and boundary vertex identification; step two: based on a full-edge folding algorithm, performing weighted edge folding on the three-dimensional model on the basis of boundary edge identification; step three: in order to eliminate chamfers in the three-dimensional model, boundary edge vertexes with approximate characteristics are identified based on a vertex clustering algorithm, and boundary vertex clustering is carried out on the boundary edge vertexes; step four: based on a vertex clustering algorithm, carrying out non-boundary vertex clustering on the basis of identifying the topological relation of the non-boundary vertices; the invention provides a simplifying method applied to a three-dimensional model of a power transmission line hardware fitting, which is based on the structural characteristics of the three-dimensional model of the power transmission line hardware fitting, keeps the appearance characteristics of the hardware fitting on the basis of reducing the data volume of the three-dimensional model of the hardware fitting, and improves the visual effect.
Description
Technical Field
The invention relates to the technical field of three-dimensional design of a power transmission line, in particular to a simplifying method applied to a three-dimensional model of a power transmission line hardware fitting.
Background
The three-dimension of the transmission line is an important development direction in the future. The national power grid company and the southern power grid company position the three-dimensional digital handover as the basic requirement of engineering design based on the operation and maintenance informatization requirement.
The hardware fitting is an important component of the three-dimensional model of the power transmission line and has the characteristics of multiple types, complex structure and the like. Meanwhile, the hardware has different requirements on data precision in different stages of processing production, design application, operation and maintenance and the like. In the design application stage, the characteristics of main size, weight and the like are mainly concerned. The operation and maintenance stage mainly realizes three-dimensional identifiable characteristics of the operation and maintenance stage.
Common expression methods of three-dimensional models include a constructive geometry method, a boundary method, a parameter method and a unit network method. The unit network method (mainly using triangle units) has excellent performance in the aspects of texture mapping, multi-detail level loading and the like, and the three-dimensional model with the expression form is used as a research object.
The vertex and the surface of an original processing model of the hardware reach tens of thousands of levels, and the whole model occupies a large amount of storage space and computational power after an insulator string is formed, so that the application range of the hardware is restricted. Therefore, simplification of the three-dimensional model of the fitting is necessary. Scholars at home and abroad carry out a great deal of research on the three-dimensional model simplification algorithm, and the common methods include a full-edge folding algorithm, a half-edge folding algorithm, a vertex clustering algorithm, a region merging algorithm, a vertex deletion algorithm and the like. But the characteristics of the transmission line hardware are not optimized, and the simplifying effect is poor.
The full-edge folding algorithm is a commonly used algorithm in three-dimensional model simplification, and the basic principle is that the vertexes at two ends of one edge are merged to a new vertex position, so that the number of vertexes and faces of the three-dimensional model is reduced.
The vertex clustering algorithm is a commonly used algorithm in three-dimensional model simplification, and the basic principle is that the vertexes of a three-dimensional space are divided into different vertex groups, and the vertexes of the same group are aggregated into one vertex, so that the number of vertexes and faces of the three-dimensional model is reduced.
Disclosure of Invention
The technical problem to be solved by the invention is as follows: the method is based on the structural characteristics of the three-dimensional hardware fitting model of the power transmission line, the appearance characteristics of the hardware fitting are reserved on the basis of reducing the data volume of the three-dimensional hardware fitting model, and the visual effect is improved.
The invention provides a simplifying method applied to a three-dimensional model of a power transmission line hardware fitting, which comprises the following steps:
the method comprises the following steps: carrying out boundary edge and boundary vertex identification;
step two: based on a full-edge folding algorithm, performing weighted edge folding on the three-dimensional model on the basis of boundary edge identification;
step three: in order to eliminate chamfers in the three-dimensional model, boundary edge vertexes with approximate characteristics are identified based on a vertex clustering algorithm, and boundary vertex clustering is carried out on the boundary edge vertexes;
step four: based on a vertex clustering algorithm, non-boundary vertex clustering is carried out on the basis of identifying the topological relation of the non-boundary vertices so as to reduce the number of triangular meshes of a flat area and reserve vertices with large influence on the characteristics of the three-dimensional model.
Furthermore, the first step specifically comprises the following steps,
firstly, initializing a boundary edge and boundary node set to be empty, and initializing an unprocessed set to be all edges and points of the three-dimensional model;
and calculating the surface included angles of all the edges, and then classifying until the unprocessed edges and the nodes are empty.
Furthermore, the calculating of the face angle specifically includes,
and calculating an included angle of normal vectors of adjacent surfaces in the three-dimensional model, wherein when the included angle is greater than a given limit value, a common edge of the adjacent surfaces is a boundary edge, a vertex of the boundary edge is a boundary vertex, and the given limit value can be 20.
Furthermore, the first step further comprises the step of,
carrying out closing judgment on the boundary edge;
when the endpoints of the boundary edge all belong to the same boundary node set, performing boundary edge closing operation to generate a boundary edge subset;
unclosed subsets of boundary edges are discarded and no boundary edges are included.
Furthermore, the weighted edge folding is specifically a full edge folding algorithm performed according to the importance of shape control of each edge.
Further, the weight edge folding includes a computation of a shrinkage error matrix, and a weight factor is introduced into the computation of the shrinkage error matrix, so as to reduce the shrinkage of the boundary edge.
Furthermore, the approaching feature specifically includes a feature that is two closed curves in geometric space, has similar trend and is close to each other.
And further, simplifying the coplanar relation vertexes by adopting a vertex clustering algorithm, wherein the fourth step also comprises the step of keeping the equivalence between the newly generated nodes and the external connection relation after the non-boundary vertex clustering is carried out and the topological relation before the clustering is kept.
By adopting the technical scheme, the invention has the beneficial effects that: through the identification of the boundary edge of the hardware fitting three-dimensional model, the boundary edge is well reserved in edge folding, and the appearance profile characteristics of the model are maintained; the combination of the three-dimensional model chamfer boundary edges is realized by judging the relation of the boundary edge subsets; for coplanar planes in the model, after the edges are folded, the area of the planes is larger, and invalid vertexes are reduced. The method greatly reduces the number of vertexes and surfaces of the hardware fitting on the basis of keeping the appearance contour characteristics of the hardware fitting three-dimensional model.
Detailed Description
Any feature disclosed in this specification may be replaced by alternative features serving equivalent or similar purposes, unless expressly stated otherwise. That is, unless expressly stated otherwise, each feature is only an example of a generic series of equivalent or similar features.
A simplification method applied to a three-dimensional model of a power transmission line hardware fitting specifically comprises the following technical processes:
step 1, identifying boundary edges and boundary vertexes, calculating included angles of normal vectors of adjacent surfaces in the hardware three-dimensional model, and obtaining a set of boundary edges and vertexes of the hardware three-dimensional model according to a given limit value, wherein the included angles are larger than the given limit value, common edges of the adjacent surfaces are defined as the boundary edges, vertexes of the boundary edges are defined as the boundary vertexes, and the given limit value can be 20.
Initializing a boundary edge and node set to be empty, processing an edge and point set to be empty, and setting an unprocessed set to be all edges and points of the three-dimensional model; randomly selecting one edge; and calculating the included angle of the connected triangular surface, if the included angle is larger than a threshold value, adding the edge into the boundary edge, and simultaneously adding nodes at two ends of the edge into the boundary nodes until the unprocessed edge and the nodes are empty.
And when the end points of a certain boundary edge belong to the same boundary node set, performing boundary edge closing operation to generate a boundary edge subset, merging and adding the boundary edge subset into the boundary edge set, discarding the unclosed boundary edge subset, and not counting the boundary edges until all the edge processing of the three-dimensional model is completed.
And 2, based on a full-edge folding algorithm, on the basis of boundary edge identification, considering that different edges have different importance in shape control, carrying out weighted edge folding on the three-dimensional model:
on the basis of boundary edge identification, the weight edge folding simplification is carried out on the three-dimensional model by considering that different edges have different importance in shape control. A weight factor is introduced in the calculation of the shrinkage error matrix, so that the shrinkage of the boundary edge is reduced. If the current edge is a boundary edge, the weight is greater than 1, otherwise, the weight value is 1. For a model of a detailed connection feature such as a groove, the value can be reduced, and the optimization rate of chamfering is improved.
And 3, based on a vertex clustering algorithm, carrying out boundary vertex clustering on boundary edge vertexes with approaching characteristics by identifying the boundary edge vertexes to eliminate chamfers in the three-dimensional model:
hardware parts have a large number of chamfers, and the appearance characteristics do not control the overall shape, but occupy a large number of points and edge storage. The chamfer is characterized by two closed curves in geometric space, the trends are similar, and the distances are close. And the vertices of the chamfered boundary are approximately uniformly distributed along the boundary edge. And when the minimum distance between any vertex in one set and a vertex in the other set is smaller than a given chamfer characteristic value, the two closed-loop boundary vertex sets have a three-dimensional model chamfer characteristic.
And after the identification of the vertexes of the chamfer boundary is finished, performing vertex clustering. And the middle point of the minimum distance connecting line of one set to the other set is adopted, so that the shape information of the original model is kept more completely.
And 4, based on a vertex clustering algorithm, carrying out non-boundary vertex clustering on the basis of identifying the topological relation of the non-boundary vertices so as to reduce the number of triangular meshes of the flat area and reserve vertices with larger influence on the characteristics of the three-dimensional model.
To process the triangular patches of a flat region, the relationship of the triangular elements is defined. A common edge or a common point exists between any two triangular surface patches in the three-dimensional model, and the three-dimensional model is called two triangles adjacent; the triangles are adjacent, the unit normal vectors are equal, and the two triangles are coplanar.
And simplifying coplanar relation vertexes by adopting a vertex clustering algorithm. And after clustering, keeping the equivalence of the newly generated node and the external connection relation with the topological relation before the original clustering. In the clustering process, the distance of elements in the class is used as a control variable, and the optimal clustering point is selected through iteration.
The process can be carried out alone or in combination with other processes except step 1.
While the foregoing description shows and describes a preferred embodiment of the invention, it is to be understood, as noted above, that the invention is not limited to the form disclosed herein, but is not intended to be exhaustive or to exclude other embodiments and may be used in various other combinations, modifications, and environments and may be modified within the scope of the inventive concept described herein by the above teachings or the skill or knowledge of the relevant art. And that modifications and variations may be effected by those skilled in the art without departing from the spirit and scope of the invention as defined by the appended claims.
Claims (8)
1. A simplification method applied to a three-dimensional model of a power transmission line hardware fitting is characterized by comprising the following steps: comprises the steps of (a) preparing a mixture of a plurality of raw materials,
the method comprises the following steps: carrying out boundary edge and boundary vertex identification;
step two: performing weighted edge folding on the three-dimensional model on the basis of boundary edge identification;
step three: identifying boundary edge vertexes with approximate characteristics, and carrying out boundary vertex clustering on the boundary edge vertexes;
step four: and carrying out non-boundary vertex clustering on the basis of identifying the topological relation of the non-boundary vertices.
2. The simplification method applied to the three-dimensional model of the power transmission line hardware fitting according to claim 1, characterized in that: the first step specifically comprises the following steps of,
firstly, initializing a boundary edge and boundary node set to be empty, and initializing an unprocessed set to be all edges and points of the three-dimensional model;
and calculating the surface included angles of all the edges, and then classifying until the unprocessed edges and the nodes are empty.
3. The simplification method applied to the three-dimensional model of the power transmission line hardware fitting according to claim 2, characterized in that: the calculation of the face angle specifically includes,
and calculating the included angle of the normal vectors of the adjacent surfaces in the three-dimensional model, wherein when the included angle is larger than a given limit value, the common edge of the adjacent surfaces is a boundary edge, and the vertex of the boundary edge is a boundary vertex.
4. The simplification method applied to the three-dimensional model of the power transmission line hardware fitting according to claim 2, characterized in that: the first step also comprises the following steps of,
carrying out closing judgment on the boundary edge;
when the endpoints of the boundary edge all belong to the same boundary node set, performing boundary edge closing operation to generate a boundary edge subset;
unclosed subsets of boundary edges are discarded and no boundary edges are included.
5. The simplification method applied to the three-dimensional model of the power transmission line hardware fitting according to claim 1, characterized in that: the weighted edge folding is specifically a full edge folding algorithm according to the importance of shape control of each edge.
6. The simplification method applied to the three-dimensional model of the power transmission line hardware fitting, according to claim 5, is characterized in that: the weighted edge folding includes a computation of a shrinkage error matrix, in which a weighting factor is introduced.
7. The simplification method applied to the three-dimensional model of the power transmission line hardware fitting according to claim 1, characterized in that: the approach features specifically include features that are two closed curves in geometric space, similar in trend, and close in distance.
8. The simplification method applied to the three-dimensional model of the power transmission line hardware fitting according to claim 1, characterized in that: and fourthly, keeping the equivalence of the newly generated node and the external connection relation after the non-boundary vertex clustering and the topological relation before clustering.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202010446175.0A CN111739166A (en) | 2020-05-25 | 2020-05-25 | Simplifying method applied to three-dimensional model of transmission line hardware |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202010446175.0A CN111739166A (en) | 2020-05-25 | 2020-05-25 | Simplifying method applied to three-dimensional model of transmission line hardware |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN111739166A true CN111739166A (en) | 2020-10-02 |
Family
ID=72647695
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202010446175.0A Pending CN111739166A (en) | 2020-05-25 | 2020-05-25 | Simplifying method applied to three-dimensional model of transmission line hardware |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN111739166A (en) |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1866299A (en) * | 2006-06-27 | 2006-11-22 | 北京航空航天大学 | Three-dimensional model simplifying method based on visual feature measurement |
| CN102306394A (en) * | 2011-08-30 | 2012-01-04 | 北京理工大学 | Three-dimensional model simplification method based on appearance retention |
| CN108961411A (en) * | 2018-07-02 | 2018-12-07 | 南京大学 | A kind of simplified method of the complex three-dimensional building model keeping external appearance characteristic |
-
2020
- 2020-05-25 CN CN202010446175.0A patent/CN111739166A/en active Pending
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1866299A (en) * | 2006-06-27 | 2006-11-22 | 北京航空航天大学 | Three-dimensional model simplifying method based on visual feature measurement |
| CN102306394A (en) * | 2011-08-30 | 2012-01-04 | 北京理工大学 | Three-dimensional model simplification method based on appearance retention |
| CN108961411A (en) * | 2018-07-02 | 2018-12-07 | 南京大学 | A kind of simplified method of the complex three-dimensional building model keeping external appearance characteristic |
Non-Patent Citations (1)
| Title |
|---|
| 李会超，冯勇，李力，梁明，谢静，车达: "架空输电线路金具三维模型简化算法研究", 电力勘测设计, vol. 2020, no. 2, 29 February 2020 (2020-02-29), pages 1 - 3 * |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN110516388B (en) | Harmonic mapping-based curved surface discrete point cloud model circular cutter path generation method | |
| CN103985155B (en) | Scattered point cloud Delaunay triangulation curved surface reconstruction method based on mapping method | |
| CN110222642B (en) | Plane building component point cloud contour extraction method based on global graph clustering | |
| CN108614939B (en) | Underground working well facility modeling method considering three-dimensional topology | |
| CN109472870B (en) | Model matching method based on grid reconstruction and multi-influence-domain correction | |
| WO2021062736A1 (en) | Division method, encoder, decoder, and computer storage medium | |
| CN113650301B (en) | 3D printing filling path planning method based on level set | |
| CN115222883A (en) | Electric power tower reconstruction method based on foundation LiDAR point cloud | |
| CN113792458B (en) | Optimization method and device for finite element triangle mesh | |
| CN110689620A (en) | Multi-level optimized mesh surface discrete spline curve design method | |
| CN111739166A (en) | Simplifying method applied to three-dimensional model of transmission line hardware | |
| CN117274517A (en) | Method for generating light-weight body frame model of urban building based on three-dimensional model | |
| CN114119628B (en) | Point cloud accurate segmentation method based on feature template | |
| Sun et al. | Automatic quadrilateral mesh generation and quality improvement techniques for an improved combination method | |
| CN103824331A (en) | Iteration generation method of hexahedral mesh model | |
| CN110738669A (en) | Adaptive octree partitioning algorithm | |
| CN108876922B (en) | Grid repairing method based on internal dihedral angle compensation regularization | |
| Xiaodong et al. | Mesh simplification based on super-face and genetic algorithm in reverse engineering | |
| Li et al. | Reasoning mechanism: An effective data reduction algorithm for on-line point cloud selective sampling of sculptured surfaces | |
| CN106652036B (en) | Two-dimensional triangular mesh generation method for efficient rendering | |
| CN108062433B (en) | Gradient curved surface layering method based on additive remanufacturing point cloud model | |
| CN112070895A (en) | High-quality real-time isosurface network generation method | |
| CN104392027A (en) | Parametric modeling method of turbine blade turbulence flow column | |
| Xiangwei et al. | A density control based adaptive hexahedral mesh generation algorithm | |
| Pan et al. | Improved QEM simplification algorithm based on local area feature information constraint |
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 |