BIM and GIS data fusion method and system based on IFC

Abstract

The invention belongs to the technical field of fusion of BIM-GIS building information and geographic information into digital twin visualization, and particularly relates to an IFC-based BIM and GIS data fusion method, which specifically comprises the following steps of preprocessing an input IFC model file, extracting key information, and performing structured output, the key information comprises geometric information, attribute information and spatial relationship information; component information of the IFC model file is mined based on the extracted and processed data, detailed geometric data and attribute data of components are obtained, and the spatial relation is refined; compressing the IFC model file; converting the BIM data into a GeoJSON (GeoJSON) format; the method comprises the following steps of: importing an IFC model file and creating a working space in a SuperMap iDesktopX, and performing geographic information format conversion on data; bIM and GIS data are loaded in the SuperMap iClient, BIM-GIS data fusion and application are carried out, and bidirectional attribute query is achieved.

Description

Technical Field

[0001] The present invention belongs to the technical field of the integration of BIM-GIS building information and geographic information into digital twin visualization, and specifically relates to a method for fusing BIM and GIS data based on IFC. Background Art

[0002] With the in-depth application of Industry 4.0 technology in the warehousing and logistics field, the integration of BIM (Building Information Modeling, which is a digital representation containing all relevant information of a building, including geometric information, attribute information, and spatial relationship information) and GIS (Geographic Information System, which is a system used to collect, store, manage, analyze, and display geospatial data) has become an important support for realizing the digital management of factories. Such integration technologies aim to combine the detailed 3D model of a building (BIM) with geospatial information (GIS) to achieve comprehensive and refined management of warehousing facilities. In China, SuperMap Software, with its products such as iDesktop, is in a leading position in the field of BIM-GIS integration solutions. The solutions of SuperMap and other mainstream integration solutions (such as the BIM plug-in of AutoDesk Forge and SuperMap of SuperMap) mainly achieve the visual integration of building models through IFC (Industry Foundation Classes) standard files. As an open and internationally common BIM data exchange standard, IFC provides a basis for data sharing between different software. Currently, these integration solutions have been able to visually display BIM models, perform basic spatial queries and analyses in the GIS environment.

[0003] Although certain progress has been made in BIM-GIS integration technology, the existing solutions represented by SuperMap have shown significant technical limitations in practical applications, especially when processing IFC files and converting them into GIS workspaces, which are mainly reflected in the following aspects:

[0004] Missing spatial attributes: It is impossible to completely extract or correctly parse the attributes of the IfcSpace entity that describes the functional areas of the warehouse, such as storage area types (refrigerated area, normal temperature area, dangerous goods area, etc.), temperature and humidity requirements, cleanliness levels, etc. This results in the GIS system being unable to effectively support refined management based on spatial attributes, such as automatically allocating storage areas according to the characteristics of goods.

[0005] Incomplete shelf information: Key information such as the shelf load-bearing limit (Pset_StorageRack.MaxLoadCapacity) cannot be extracted, resulting in the inability of the goods location allocation algorithm to automatically verify the matching of stack height and bearing capacity, and the virtual increase rate of the warehouse volume is 25%.

[0006] Lack of path information: Entities such as IfcBuildingElementProxy used to represent obstacles or virtual paths in the IFC model cannot be recognized and utilized, and attributes that restrict passage, such as IfcDoor.OverallHeight, cannot be extracted. This causes the path planning system to be unable to accurately perceive the actual passage conditions in the warehouse. For example:

[0007] It is impossible to recognize that only specific types of vehicles are allowed to pass in certain areas. The real-time opening and closing state of the door cannot be obtained

[0008] (IfcDoor.CurrentState), resulting in the path planning may include closed passages. Temporary obstacles in the warehouse, such as stacked goods, cannot be obtained. Lack of key path network semantic information, such as one-way / two-way passage, speed limit, load-bearing requirements, etc. Summary of the Invention

[0009] To solve the above technical problems, the present invention provides a method for fusing BIM and GIS data based on IFC. The method includes the following steps:

[0010] Preprocess the input IFC model file, extract key information and output it in a structured manner. The key information includes geometric information, attribute information, and spatial relationship information;

[0011] Based on the data after extraction and processing, mine the component information of the IFC model file, obtain the detailed geometric data and attribute data of the components, and refine the spatial relationship; and compress the IFC model file to reduce the data volume and improve the processing efficiency;

[0012] Convert BIM data into GeoJSON (an open standard format for encoding various geographic data structures, based on JSON (JavaScript Object Notation)) format, including geometric data conversion and non-geometric attribute association;

[0013] Import the IFC model file and create a workspace in SuperMap iDesktopX (SuperMap iDesktopX is a professional GIS desktop software that provides functions such as data processing, map making, and spatial analysis). And perform geographic information format conversion on the GeoJSON format data converted from BIM data;

[0014] Load the compressed IFC file and GIS data in SuperMap iClient (SuperMap iClient is a Web-based GIS development platform for building WebGIS applications);

[0015] Perform BIM-GIS data fusion and application, including the overlay display of BIM models and GIS data, and the association of BIM components and GIS features through unique identifiers to achieve two-way attribute query.

[0016] Furthermore, preprocess the input IFC file, extract key information and output it in a structured manner, including:

[0017] Extract information using an IFC parsing engine;

[0018] Output the information in JSON format, including the globally unique identifier (GUID) of the component.

[0019] Furthermore, based on the extracted data, deeply mine the IFC component information, obtain the detailed geometric data and attribute data of the components, and refine the spatial relationships, including:

[0020] Obtain a more refined geometric representation of the IFC component, such as: higher geometric accuracy, more vertices / control points, smaller triangular patches / mesh cells. Through the association relationships in the IFC standard (such as IfcRelContainedInSpatialStructure, IfcRelConnectsElements, etc.), obtain the spatial hierarchical relationships and connection relationships between IFC components;

[0021] If the spatial relationships in the IFC model are incomplete, automatically deduce the spatial relationships based on the geometric information and attribute information of the components.

[0022] Furthermore, compress the IFC model, including:

[0023] Compress the IFC model using a spatial data compression algorithm (such as octree voxelization); set the compression parameters according to application requirements and accuracy requirements.

[0024] Furthermore, convert the BIM data into GeoJSON format, including:

[0025] Convert the geometric data of the BIM components in the IFC file into GeoJSON geometric objects (points, lines, faces);

[0026] Convert the attribute data of the BIM components in the IFC file into the attributes of GeoJSON features;

[0027] Convert the spatial relationships of the BIM components in the IFC file into the association relationships or attributes between GeoJSON features.

[0028] Furthermore, converting the BIM data into GeoJSON format also includes:

[0029] Use the unique identifier GUID of the BIM component in the IFC file as the association key to ensure the consistency of BIM data and GIS data.

[0030] Furthermore, perform IFC model import and workspace creation in SuperMapiDesktopX, and perform geographic information format conversion on GeoJSON data.

[0031] Use the IFC import function of SuperMap iDesktopX to import the compressed IFC file;

[0032] Create a new SuperMap workspace file;

[0033] In the workspace, create a data source for storing the IFC model, attribute data, and the converted GIS data.

[0034] Furthermore, in SuperMap iDesktopX, define a coordinate system for the GeoJSON data;

[0035] Import the GeoJSON data as a dataset in SuperMap iDesktopX;

[0036] According to needs, convert the feature type in GeoJSON to other types supported by SuperMap;

[0037] According to needs, adjust the attribute field name, type, or add new attribute fields.

[0038] According to another aspect of the present invention, there is also provided an IFC-based BIM and GIS data fusion system, the system includes:

[0039] IFC preprocessing module, used to preprocess the input IFC file, extract key information and output it in a structured manner;

[0040] Component information mining and spatial relationship refinement module, used to deeply mine IFC component information, obtain detailed geometric and attribute data, and refine spatial relationships;

[0041] IFC model compression module, used to compress the IFC model;

[0042] BIM data conversion module, used to convert BIM data into GeoJSON format;

[0043] SuperMap platform processing module, used to perform IFC model import, workspace creation, and geographic information format conversion of GeoJSON data in SuperMap iDesktopX;

[0044] A data loading module, which is used to load BIM and GIS data in SuperMapiClient;

[0045] A data fusion and application module, which is used to perform BIM-GIS data fusion and application.

[0046] The advantages of the present invention are as follows:

[0047] In view of the complex IFC file structure and information redundancy, directly applying it to the GIS platform will result in excessive data volume, slow loading, or even inability to load, and some data is prone to loss during the conversion process. By preprocessing the IFC file, key information (geometry, attributes, spatial relationships) is extracted and output in a structured manner. Further, a spatial data compression algorithm (such as octree voxelization) is used to compress the IFC model. This effectively reduces the data volume, improves the loading and display efficiency on the GIS platform, and reduces the problem of data loss.

[0048] By associating BIM components and GIS features through the unique identifier GUID, a two-way attribute query function is realized on the SuperMap platform. Users can directly query the attribute information of BIM components in the GIS environment, and can also query the attribute information of GIS features in the BIM model, realizing the interconnection and interoperability of information. It solves the problem of weak correlation between the BIM model and GIS data, making it difficult to achieve two-way attribute query and information interconnection, which hinders the in-depth application of BIM-GIS integration.

[0049] In the stage of component information mining, the spatial relationship of IFC components is refined. If the spatial relationship in the IFC model is incomplete, the spatial relationship is automatically deduced based on the geometric information and attribute information of the components, improving the usability of the model data. It solves the problem that the data quality of some IFC models is poor and the spatial relationship is incomplete, affecting the effect of BIM-GIS integration. Description of the Drawings

[0050] Figure 1 is the process schematic diagram of the present invention;

[0051] Figure 2 is the process schematic diagram of information extraction by the IfcOpenShell engine. Detailed Embodiments

[0052] The principles and features of the present invention are described below with reference to the accompanying drawings. The examples given are only used to explain the present invention and are not intended to limit the scope of the present invention.

[0053] Refer to Figure 1 , a BIM and GIS data fusion method based on IFC provided by the present invention includes the following steps:

[0054] Step 101: IFC Preprocessing and Key Information Extraction

[0055] Extract the key information required for factory warehouse logistics management from the IFC file and output it in a structured manner. Extract key information:

[0056] Spatial information: The initial geometry and location of warehouses, shelves, doors, and aisles. Logistics attributes: Shelf load-bearing capacity, aisle width, etc. Path information: The initial representation of the aisle (IfcSpace or IfcPathElement).

[0057] Use the IFC parsing engine (IfcOpenShell) to extract information, as Figure 2 shown.

[0058] Output the information in JSON format, including the component GUID.

[0059] Step 102: In-depth Mining of Component Information and Path Refinement

[0060] Based on the data extracted in Step 101, mine hidden information, obtain detailed information of key components, and refine the aisle path.

[0061] Precise geometry extraction of key components:

[0062] Shelf: Vertex coordinates (for collision detection, etc.). Aisle and connection point refinement (key):

[0063] In-depth information mining of IfcSpace: Not only extract the boundaries of IfcSpace, but also trace its original, unmodified shape, size, and orientation information indirectly through IfcLocalPlacement, IfcRepresentation, etc.

[0064] Determination of connection points:

[0065] If the aisle is represented by IfcPathElement, combine relevant IFC relationships (such as

[0066] IfcRelConnectsPathElements) and geometric analysis to determine its precise connection points.

[0067] If the aisle is represented by IfcSpace, use the original geometric information of IfcSpace mined in the previous step, combined with adjacent components (such as IfcWall, IfcDoor), to perform geometric calculations to determine the connection points.

[0068] If the IFC model lacks path elements, automatically generate paths and connection points based on IfcSpace and other spatial information.

[0069] Generate the channel centerline based on the determined connection points.

[0070] Step 103: IFC model compression

[0071] This step aims to reduce the data volume of the IFC model, improve the efficiency of data processing and transmission, and retain key information as much as possible.

[0072] Select the octree voxelization algorithm as the compression method. Set the voxel size and the maximum depth of the octree according to the scale and accuracy requirements of the factory warehouse model. For example, the voxel side length in general areas is set to 0.1 meters, the voxel side length in key areas such as doors and windows is set to 0.05 meters, and the maximum depth of the octree is set to 8.

[0073] Step 104: Convert BIM data to GeoJSON

[0074] This step converts the BIM depth information extracted in Step 102 into the GeoJSON format, laying the foundation for subsequent GIS applications.

[0075] Geometric data conversion:

[0076] IfcSpace is converted to the Polygon type in GeoJSON, including its original shape, size, and orientation information (from the excavation results in Step 102).

[0077] Shelves: Convert to the Point (for quick positioning) or Polygon (for detailed analysis) type in GeoJSON, including vertex coordinates.

[0078] Doors: Convert to the Point type in GeoJSON, and an attribute can be added to represent the opening direction.

[0079] Channels:

[0080] The channel width attribute can generate a buffer and be converted to a Polygon to represent the passable area.

[0081] Build a network dataset and convert it to a special format of GeoJSON (for example, the edges are LineString, the nodes are Point, and connection relationship attributes are added).

[0082] Point pair information: Convert the point pair information (such as channel connection points) extracted in Step 102 to the MultiPoint or LineString type in GeoJSON, depending on the use of the point pair.

[0083] Non-geometric attribute association:

[0084] Use the non-geometric attributes (such as load-bearing capacity, height, type, material, etc.) extracted in steps 101 and 102 as the properties of the GeoJSON Feature.

[0085] Use the GUID as the association key to ensure data consistency.

[0086] Step 105: IFC model import and workspace creation in SuperMap iDesktopX

[0087] In this step, use the SuperMap iDesktopX platform to process the compressed IFC model and create a workspace to prepare for subsequent BIM-GIS data fusion.

[0088] Use the IFC import function of SuperMap iDesktopX to import the compressed IFC file generated in step 103.

[0089] Check whether the imported IFC model is correctly displayed and whether the geometric and attribute information is complete to ensure data accuracy.

[0090] Create a new SuperMap workspace file (*.sxwu) to store BIM and GIS data, as well as the results of subsequent data processing and analysis. In the workspace, create data sources for storing the IFC model, attribute data, and converted GIS data.

[0091] Step 106: GeoJSON data geographic information format conversion

[0092] In this step, process the GeoJSON data in SuperMap iDesktopX to make it compatible with the SuperMap platform and prepare for subsequent data fusion.

[0093] In SuperMap iDesktopX, define the correct coordinate system for the GeoJSON data generated in step 105 to ensure that the data is displayed at the correct geographical location.

[0094] Import the GeoJSON data as a dataset (points, lines, polygons, etc.) in SuperMap iDesktopX to achieve data conversion and integration.

[0095] According to needs, convert the feature types in GeoJSON to other types supported by SuperMap (such as point to polygon, line to network) to meet specific analysis requirements. According to needs, adjust the attribute field names, types, or add new attribute fields.

[0096] Step 107: Data loading in SuperMap iClient

[0097] In this step, the SuperMapiClient is used to load BIM and GIS data to prepare for subsequent visualization and analysis.

[0098] In SuperMapiClient, connect to the workspace file created in step 106 to establish a connection with the data.

[0099] Load the compressed IFC model from the workspace to visualize the BIM data.

[0100] Load the GeoJSON data converted in step 107 to visualize the GIS data.

[0101] Step 108: BIM-GIS Data Fusion and Application

[0102] In this step, the BIM and GIS data are fused in SuperMapiClient, and spatial analysis and applications are performed based on the fused data to achieve the intelligentization of factory warehouse logistics management.

[0103] In SuperMap iClient, the BIM model and GIS data are overlaid and displayed as different layers to achieve data integration and visualization.

[0104] Associate BIM components and GIS features through GUID to achieve two-way attribute query.

[0105] According to another aspect of the present invention, there is also provided an IFC-based BIM and GIS data fusion system, which includes:

[0106] IFC preprocessing module, used to preprocess the input IFC file, extract key information and output it in a structured manner;

[0107] Component information mining and spatial relationship refinement module, used to deeply mine IFC component information, obtain detailed geometric and attribute data, and refine spatial relationships;

[0108] IFC model compression module, used to compress the IFC model;

[0109] BIM data conversion module, used to convert BIM data into GeoJSON format;

[0110] SuperMap platform processing module, used to import the IFC model, create a workspace and convert the GeoJSON data into a geographic information format in SuperMap iDesktopX;

[0111] A data loading module, which is used to load BIM and GIS data in SuperMap iClient;

[0112] A data fusion and application module, which is used to conduct BIM-GIS data fusion and application.

[0113] The above are only the preferred embodiments of the present invention, and are not intended to limit the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present invention shall be included within the protection scope of the present invention.

Claims

1. A BIM and GIS data fusion method based on IFC, characterized in that, The method includes: Preprocess the input IFC model file, extract key information and output it in a structured manner. The key information includes geometric information, attribute information, and spatial relationship information; Based on the data after extraction and processing, mine the component information of the IFC model file, obtain the detailed geometric data and attribute data of the components, refine the spatial relationship, and compress the IFC model file; Convert BIM data into GeoJSON format, including geometric data conversion and non-geometric attribute association; Perform compressed import and workspace creation in SuperMap iDesktopX, and perform geographic information format conversion on the GeoJSON format data converted from BIM data; Load the workspace created by BIM in SuperMap iDesktopX and the GIS data to be fused in SuperMap iClient; Perform BIM-GIS data fusion and application, including the overlay display of the BIM model and GIS data, and associating BIM components and GIS features through a unique identifier to achieve two-way attribute query.

2. The method for fusing BIM and GIS data based on IFC according to claim 1, wherein, The preprocessing of the input IFC model file, extracting key information and outputting it in a structured manner includes: Extract information using an IFC parsing engine; Output the information in JSON format, including the unique identifier GUID of the component.

3. A BIM and GIS data fusion method based on IFC according to claim 1, characterized in that, Based on the extracted data, mining IFC component information, obtaining the detailed geometric data and attribute data of the components, and refining the spatial relationship includes: Obtain the geometric representation of the IFC component, such as geometric accuracy, vertices / control points, triangular patches / mesh cells; Through the association relationships in the IFC standard, that is, the containment relationships between components in the IFC file and the connection relationships between components, obtain the spatial hierarchical relationships and connection relationships between IFC components; If the spatial relationship in the IFC model is incomplete, automatically deduce the spatial relationship based on the geometric information and attribute information of the components.

4. A BIM and GIS data fusion method based on IFC according to claim 1, characterized in that, The compression of the IFC model includes: Compress the IFC model using the spatial data compression algorithm octree voxelization; Set compression parameters according to application requirements and accuracy requirements.

5. A method for fusing BIM and GIS data based on IFC according to claim 1, characterized in that The conversion of BIM data in the compressed IFC file into GeoJSON format includes: Convert the geometric data of BIM components in the IFC file into GeoJSON geometric objects (points, lines, surfaces); Convert the attribute data of BIM components in the IFC file into the attributes of GeoJSON features; Convert the spatial relationship of BIM components in the IFC file into the association relationship or attribute between GeoJSON features.

6. A BIM and GIS data fusion method based on IFC according to claim 1, characterized in that, The conversion of BIM data in the IFC file into GeoJSON format also includes: Use the unique identifier GUID of the required combined components such as spatial information and node information as the association key to ensure the consistency of BIM data and GIS data.

7. A BIM and GIS data fusion method based on IFC according to claim 1, characterized in that, Perform IFC model import and workspace creation in SuperMap iDesktopX, and perform geographic information format conversion on GeoJSON data; Use the IFC import function of SuperMap iDesktopX to import the compressed IFC file; Create a new SuperMap workspace file; In the workspace, create a data source for storing the IFC model, attribute data, and the converted GIS data.

8. The method for fusing BIM and GIS data based on IFC according to claim 1, wherein, In SuperMap iDesktopX, define the coordinate system for the GeoJSON data; Import the GeoJSON data as a dataset in SuperMap iDesktopX; Convert the feature type in GeoJSON to other types supported by SuperMap; Adjust the attribute field names, types, or add new attribute fields.

9. An IFC-based BIM and GIS data fusion system, characterized in that, The system includes: An IFC preprocessing module for preprocessing the input IFC file, extracting key information, and outputting it in a structured manner; A component information mining and spatial relationship refinement module for deeply mining IFC component information, obtaining detailed geometric and attribute data, and refining spatial relationships; An IFC model compression module for compressing the IFC model; A BIM data conversion module for converting BIM data into the GeoJSON format; A SuperMap platform processing module for importing the IFC model, creating a workspace, and converting the GeoJSON data into a geographic information format in SuperMap iDesktopX; A data loading module for loading BIM and GIS data in SuperMap iClient; A data fusion and application module for performing BIM-GIS data fusion and application.

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