CN105468869B - Topological relation analysis method of PDS model - Google Patents
Topological relation analysis method of PDS model Download PDFInfo
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- CN105468869B CN105468869B CN201510974429.5A CN201510974429A CN105468869B CN 105468869 B CN105468869 B CN 105468869B CN 201510974429 A CN201510974429 A CN 201510974429A CN 105468869 B CN105468869 B CN 105468869B
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- G06F30/367—Design verification, e.g. using simulation, simulation program with integrated circuit emphasis [SPICE], direct methods or relaxation methods
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Abstract
The invention provides a topological relation analysis method of a PDS model, which comprises the following steps: s1, defining a PDS topological relation data structure; s2, acquiring a graphic file path corresponding to each model in the PDS project; s3, sequentially scanning the graphic files corresponding to the PDS model to obtain the graphic elements representing the model elements in the file; s4, acquiring the feature code to determine the identity of the element; s5, acquiring the key point coordinates of the element for analyzing the topological relation; repeating S2 through S5; and S6, finding out the topological relation of all the elements through the coordinate matching of the key points. The method for analyzing the topological relation of the PDS model, provided by the invention, can automatically acquire all professional topological relations including pipelines, equipment, bridges and the like in the PDS model, store the topological relations in the database and convert unstructured graphic information into structured data in the database, so that the flexibility and readability of the topological relation data of the PDS model are remarkably improved.
Description
Technical Field
The invention relates to a three-dimensional model processing method, in particular to a topological relation analysis method of a PDS model.
Background
The PDS (plant Design System) is a widely used three-dimensional Design software. The PDS software is used as an integrated collaborative design system with multiple specialties participating in, can rapidly help each professional designer to carry out three-dimensional modeling and design inspection, and greatly improves the working efficiency and the design quality. PDS software has found widespread use and has had countless success in the chemical and energy industries.
With the rapid advance of computer technology and the continuous advance of industrial automation process, the integration of design and analysis has become a great trend. The PDS stores the topological relation in the model in a graphic file instead of a database, the topological relation data is not flexible due to unstructured data, and the topological relation data of the three-dimensional model is very important for subsequent analysis and calculation, so that the PDS software and the subsequent analysis software cannot directly perform data interaction and need to perform interface development. Research shows that no mature PDS model topological relation analysis software exists in the market at present.
Disclosure of Invention
Aiming at the defects of the prior art, the invention provides a topological relation analysis method of a PDS model.
The topological relation analysis method of the PDS model comprises the following steps:
s1, defining a PDS topological relation data structure, wherein the data structure can completely represent all topological relations of each PDS component;
s2, acquiring a graphic file path corresponding to each model in the PDS project;
s3, sequentially scanning the graphic files corresponding to the PDS model to obtain the graphic elements representing the model elements in the file, wherein the graphic files corresponding to the PDS model are DGN files;
s4, obtaining the feature code of the graphic element corresponding to the model element for determining the identity of the element;
s5, obtaining the key point coordinates of the element corresponding to the graphic element of the model element for analyzing the topological relation;
repeating S2 to S5 until the DGN file of the whole PDS project is scanned, and the feature codes and the key point coordinates of all elements in the project are detected;
and S6, finding out the topological relations of all the elements through the coordinate matching of the key points, storing the topological relations into a topological relation data structure defined in S1, and storing the topological relations into a database to form structured data.
Preferably, the acquiring of the PDS model corresponding graph file path of S2 should find the graph file path corresponding to each model from the database corresponding data table of the PDS project.
Preferably, the sequential scanning graphics file internal model element of S3 includes the following steps:
s3.1, extracting all elements from the graphic file, wherein all non-graphic elements are filtered out in scanning and only all graphic elements are reserved as the elements of the PDS are necessarily graphic elements;
and S3.2, searching for an element which represents the PDS model element in the scanned graphic elements, removing the garbage element, and judging whether the element has DMRS Link (feature code attached to the graphic element by PDS software) or not according to the standard, wherein the element is the PDS model element if the element exists, and the element is the garbage element if the element does not exist.
Preferably, the obtaining the feature code and determining the identity of the component in S4 includes the following steps:
s4.1, judging a method for reading the element feature code and reading a DMRS link of the element according to the difference of the types of the graphic elements;
and S4.2, if the pipeline or bridge is professional, acquiring the DMRS link of the center line corresponding to the component from the DMRS link, and using the DMRS link to acquire the attribute information stored on the center line.
Preferably, the step of obtaining the key point coordinates of the element for analyzing the topological relation in S5 includes the following steps:
s5.1, judging the storage position of the key point coordinate according to the difference of the graphic element types, wherein if the content element exists, the key point is two end face coordinates;
and S5.2, acquiring the coordinates of the key points according to the judgment result of the S5.1, and storing the coordinates into a defined topological relation data structure.
Compared with the prior art, the invention has the following beneficial effects:
1. the method for analyzing the topological relation of the PDS model can automatically acquire all professional topological relations including pipelines, equipment, bridges and the like in the PDS model, store the topological relations in the database and convert unstructured graphic information into structured data in the database, so that the flexibility and readability of the topological relation data of the PDS model are remarkably improved, repeated development and manual labor when the PDS model topological relation data are required to be used subsequently are avoided, and the design efficiency and quality are greatly improved.
2. The method for analyzing the topological relation of the PDS model provides data guarantee for PDS software and other software interfaces.
3. The method for analyzing the topological relation of the PDS model provided by the invention is fully automatically completed in the whole process, does not need human intervention, and is simple and convenient to operate and high in production efficiency.
Drawings
Fig. 1 is a flowchart illustrating a PDS model topology relationship analysis method according to a preferred embodiment of the present invention.
Fig. 2 is a schematic flow chart of acquiring a feature code and a key point coordinate of a graphic element from a single graphic file according to a preferred embodiment of the present invention.
Fig. 3 is a schematic flow chart of the process of completing the topological relational structure model by the key point matching algorithm in accordance with the preferred embodiment of the present invention.
Fig. 4 is a schematic view of a pipe connection.
Detailed Description
In order to make the aforementioned objects, features and advantages of the present invention comprehensible, embodiments accompanied with figures are described in further detail below.
As shown in fig. 1, the method for analyzing the topological relation of the PDS model includes the following steps:
and S1, defining a PDS topological relation data structure, wherein the data structure can completely represent all topological relations of each PDS component, and therefore the data structure needs to reflect not only the type and the identity of the element of the data structure, but also the connection relation between the current element and other elements.
And S2, acquiring a graphic file path corresponding to each model in the PDS project. The storage path of the graphic file has detailed records in the database of the PDS project, and the specific record position is in the pd table in the PDS database. Wherein, the graph file of the PDS software is a DGN file created by the Microstation software.
And S3, sequentially scanning the graphic files corresponding to the PDS model to obtain the graphic elements representing the model elements in the file. During scanning, non-graphic elements in the DGN file can be ignored, because the elements of the PDS are only graphic elements; meanwhile, for the graphic elements without any link data link, the graphic elements can be omitted, because the elements in the PDS model have data links to ensure the association of the graphic elements with the database, and therefore the graphic elements scanned in S3 should all be graphic elements with data links.
And S4, acquiring the feature code of the graphic element corresponding to the graphic element of the model element for determining the identity of the element, wherein the feature code is also a connection bridge between the graphic element and the attribute data stored in the database. The characteristic codes are stored in DMRS links of the graphic elements, and each element of each model has a unique characteristic code corresponding to the characteristic code. For the pipe and bridge profession, the graphic elements of the parts comprise a plurality of DMRS links, the first one represents the characteristic code of the part, and the rest represents the characteristic code of the center line corresponding to the part, so that the parts and the center line can be associated as long as the center line consistent with the characteristic code of the center line in the parts in the model is found. As shown in FIG. 4, "linkage 2" of 01 should be equal to "linkage 1" of 02, in such a way that the part can be aligned with the centerline.
And S5, acquiring the key point coordinates of the element corresponding to the graphic element of the model element for carrying out topological relation analysis. The key point coordinates refer to the endpoint coordinates of each element, and the topological relation between the element and other elements and the spatial coordinates of the element can be known through the end face coordinates.
The key point coordinate acquisition modes of the model elements of the system are different corresponding to different specialties. The following describes how to obtain the coordinates of the key points by taking the pipeline components of the pipeline speciality as an example.
For the pipe element, its corresponding graphic element is a simple element, and therefore its end coordinates are the two end coordinates center 1 and center2 of the cylinder.
The topological relation related information of each element can be obtained through S4 and S5, and the topological relation related information of all elements in each model can be obtained through S3. The flow chart corresponding to the three steps S3, S4 and S5 is shown in fig. 2.
S2 through S5 are then repeated until the DGN file of the entire PDS project has been scanned, and the signatures and key point coordinates of all the components in the project have been detected. Since not all the components of each model are connected with the components inside the model, and there is necessarily a connection relationship between the models, the acquisition of the topological relationship information of all the components of the whole project must be completed to generate a complete topological relationship.
And finally, S6, finding out the topological relations of all the elements through the coordinate matching of the key points, storing the topological relations into the topological relation data structure defined in the step S1, and storing the topological relations into a database to form structured data. The whole process of S6 is as shown in fig. 3, first, the obtained topological relation information data of all elements in the project are read, then the topological relation information data (i.e. the feature code and the end face coordinates of each element) of each element are read one by one, the process is to correspond to each end face coordinate of the current element, whether there is a matching coordinate point in the topological relation confidence data of the whole project is found, if there is no matching point, the current end face is suspended, if there is a matching coordinate point, the current element is connected to the element, if there is more than one matching, an arrangement error occurs and is recorded, until all end faces of the current element are completely matched, the topological relation of the current element is obtained, and the next element is switched, and so the process is repeated until all elements complete the obtaining of the topological relation information. As shown in FIG. 4, if the pipe is connected to an elbow, the "cp 2 location" 04 of the pipe should coincide with the "cp 1 location" 05 of the elbow. And finally, the completed topological relation data is stored in a database, so that the unstructured PDS topological relation is converted into structured database data, and the flexibility and expansibility of the program are improved.
Compared with the prior art, the invention has the following beneficial effects:
1. the method for analyzing the topological relation of the PDS model provided by this embodiment can automatically obtain all professional topological relations including pipelines, equipment, bridges and the like in the PDS model, store the topological relations in the database, and convert unstructured graphical information into structured data in the database, so that the flexibility and readability of the topological relation data of the PDS model are significantly improved, repeated development and manual labor when the PDS model topological relation data needs to be used subsequently are avoided, and the design efficiency and quality are greatly improved.
2. The method for analyzing the topological relation of the PDS model provided by the embodiment provides data guarantee for PDS software and other software interfaces.
3. The method for analyzing the topological relation of the PDS model provided by the embodiment has the advantages that the whole process is completed automatically, manual intervention is not needed, the operation is simple and convenient, and the production efficiency is high.
The embodiments in the present description are described in a progressive manner, each embodiment focuses on differences from other embodiments, and the same and similar parts among the embodiments are referred to each other. For the system disclosed by the embodiment, the description is relatively simple because the system corresponds to the method disclosed by the embodiment, and the relevant points can be referred to the method part for description.
Skilled artisans may implement the described functionality in varying ways for each particular application, but such implementation decisions should not be interpreted as causing a departure from the scope of the present invention.
It will be apparent to those skilled in the art that various changes and modifications may be made in the invention without departing from the spirit and scope of the invention. Thus, if such modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalents, the present invention is also intended to include such modifications and variations.
Claims (5)
1. A topological relation analysis method of a PDS model is characterized by comprising the following steps:
s1, defining a PDS topological relation data structure, wherein the data structure can completely represent all topological relations of each PDS component;
s2, acquiring a graphic file path corresponding to each model in the PDS project;
s3, sequentially scanning the graphic files corresponding to the PDS model to obtain the graphic elements representing the model elements in the file, wherein the graphic files corresponding to the PDS model are DGN files;
s4, obtaining the feature code of the graphic element corresponding to the model element for determining the identity of the element;
s5, obtaining the key point coordinates of the element corresponding to the graphic element of the model element for analyzing the topological relation;
repeating S2 to S5 until the DGN file of the whole PDS project is scanned, and the feature codes and the key point coordinates of all elements in the project are detected; the key point coordinates refer to the endpoint coordinates of each element, and the topological relation between the element and other elements and the self space coordinates can be known through the end face coordinates;
s6, finding out the topological relations of all elements through the coordinate matching of the key points, storing the topological relations into a topological relation data structure defined by S1, and storing the topological relations into a database to form structured data;
wherein, finding out the topological relation of all the elements through the coordinate matching of the key points comprises the following steps: firstly, reading obtained topological relation information data of all elements in an item, then reading the topological relation information data of each element one by one, namely the feature code and the end face coordinate of each element, searching whether matched coordinate points exist in the topological relation information data of the whole item, suspending the current end face if the matched coordinate points do not exist, connecting the current element with the element if one coordinate point is matched, and if more than one coordinate point is matched, generating a layout error and recording until all the end faces of the current element are completely matched, the topological relation of the current element is obtained, and switching to the next element, thus circulating until all the elements finish the acquisition of the topological relation information.
2. The method for resolving topological relation of PDS model as claimed in claim 1, wherein said obtaining the graph file path corresponding to the PDS model of S2 is to find the graph file path corresponding to each model from the database corresponding data table of the PDS project.
3. The method for resolving topological relation of PDS model according to claim 1, wherein said sequential scanning pattern file internal model element of S3 comprises the steps of:
s3.1, extracting all elements from the graphic file, wherein all non-graphic elements are filtered out in scanning and only all graphic elements are reserved as the elements of the PDS are necessarily graphic elements;
and S3.2, searching for an element representing the PDS model element in the scanned graphic elements, removing the garbage element, and judging whether the element has DMRSLinkage or not according to the standard, wherein the element is the PDS model element if the element exists, and the element is the garbage element if the element does not exist.
4. The PDS model topological relation resolution method of claim 1, wherein said obtaining feature codes and determining component identities of S4 comprises the steps of:
s4.1, judging a method for reading the feature codes of the elements and reading the feature codes DMRSlinkage of the elements according to the difference of the types of the graphic elements;
s4.2, if the pipeline or bridge is professional, the DMRSlinkage of the component corresponding to the central line is acquired from the DMRSlinkage and is used for acquiring the attribute information stored on the central line.
5. The PDS model topological relation resolution method of claim 1, wherein said obtaining key point coordinates of elements of S5 for performing topological relation analysis comprises the steps of:
s5.1, judging the storage position of the key point coordinate according to the difference of the types of the graphic elements;
and S5.2, acquiring the coordinates of the key points according to the judgment result of the S5.1, and storing the coordinates into a defined topological relation data structure.
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| CN109272571B (en) * | 2018-08-22 | 2020-12-15 | 上海核工程研究设计院有限公司 | System and method for converting PDS three-dimensional data into Flowmaster model |
| CN109117564B (en) * | 2018-08-22 | 2021-01-26 | 上海核工程研究设计院有限公司 | System and method for converting PDS three-dimensional model into RELAP5 model |
| CN110096415A (en) * | 2019-05-15 | 2019-08-06 | 北京首汽智行科技有限公司 | A kind of data monitoring method based on topological relation |
| CN110109999B (en) * | 2019-05-24 | 2023-06-20 | 上海核工程研究设计院股份有限公司 | System for converting SMART3D three-dimensional model into FlowMaster model and conversion method |
| CN111368381B (en) * | 2020-03-06 | 2024-02-23 | 上海天麦能源科技有限公司 | Intelligent information processing method and system for water pipe network |
| CN114896792B (en) * | 2022-05-16 | 2024-06-21 | 上海核工程研究设计院股份有限公司 | Space topological relation analysis and topological network model establishment method for S3D air duct model |
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