Dynamic cutting and updating method for non-manifold grid geologic body based on dredging engineering
By using a non-manifold mesh geological body dynamic cutting and updating method, the problem of real-time dynamic updating of geological bodies was solved, realizing efficient and real-time updating and rendering of the model, and improving the construction efficiency and quality of dredging projects.
Patent Information
- Application Number
- CN202511163908.9
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-08-20
- Publication Date
- 2025-12-02
AI Technical Summary
Existing technologies struggle to achieve real-time dynamic updates and visualization of geological bodies, resulting in insufficient model accuracy, high computational load, excessive resource consumption, and an inability to quickly integrate real-time data, thus impacting the refined management and construction efficiency of dredging projects.
A dynamic cutting and updating method for geological bodies using non-manifold meshes is adopted. This method involves importing a 3D model and converting it into a non-manifold mesh format, using LOD lightweight processing and the α-shape algorithm to extract the contour, and combining non-manifold mesh layer cutting and octree indexing to perform local mesh reconstruction and data updates, thereby realizing real-time simulation of geological body changes.
It enables real-time dynamic updates of geological bodies, ensuring the continuity and consistency of model changes, reducing computational load and resource consumption, and improving the construction efficiency and quality of dredging projects.
Smart Images
Figure CN121053333A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of geological modeling and engineering application technology, and in particular to a method for dynamic cutting and updating of non-manifold grid geological bodies based on dredging engineering. Background Technology
[0002] In dredging projects, changes in geological bodies (such as cutting and volume changes) are difficult to visualize and update in real time using traditional geological modeling methods. Most methods involve replacing old geological bodies with newly constructed ones. Because this "new-replacement" approach, rather than continuous dynamic cutting and updating of existing geological bodies, introduces unnecessary geometric errors during the change process. This leads to discrepancies between the geological body's morphology and volume information and the actual situation, compromising accuracy and reducing model reliability. It fails to accurately reflect the true spatial distribution and detailed changes of the geological body after cutterhead cutting, hindering the refined management of dredging projects. Furthermore, each cut requires time to rebuild the entire 3D model, making it difficult to quickly integrate real-time data. The time-consuming process of generating and replacing new models results in delays in dredging progress monitoring and parameter optimization. Under rapid operations or complex geological conditions, it is difficult to provide timely and effective decision-making support for construction command. Furthermore, since each update requires building a completely new model, the computational load is large and the storage resources are consumed, which is not conducive to efficient operation on resource-constrained terminal devices or cloud systems. In situations such as multi-vessel collaborative operations, segmented dredging, and precision excavation, the lack of a continuously dynamically updated model makes it difficult to accurately synchronize construction management and progress monitoring, affecting project efficiency and quality. Summary of the Invention
[0003] The technical problem to be solved by the present invention is to overcome the shortcomings of the existing technology and provide a method for dynamic cutting and updating of non-fluid grid geological bodies based on dredging engineering. This method is applicable to engineering projects such as waterway dredging and seabed excavation, and enables real-time simulation of geological body changes, volume calculation and dynamic updating.
[0004] This invention is achieved through the following technical solution:
[0005] A method for dynamically cutting and updating non-manifold grid geological bodies based on dredging projects includes the following steps:
[0006] S1. Import the 3D model of the geological body and convert it to a non-manifold mesh format;
[0007] S2. The imported three-dimensional model of the geological body is statically simplified and lightweighted using LOD, and a dynamic optimization mechanism is established using the LOD algorithm. The three-dimensional model of the geological body at the cutterhead construction location can display the detailed process of the cutterhead excavation of the geological body, while the model at locations far from the cutterhead is blurred.
[0008] S3. Load the cutting body and extract the outer contour of the cutting body;
[0009] S4. A non-manifold mesh layered cutting method is adopted to cut the geological body according to the real-time running trajectory of the cutting body, and the mesh data after cutting is updated.
[0010] S5. Encode and transmit the cut grid data to update the data of the target area in the geological body affected by the cutting;
[0011] S6. Reconstruct and render the new geological body dataset, automatically coloring the cut surfaces according to lithology to form an updated 3D model of the geological body.
[0012] According to the above technical solution, preferably, in step S2, "establishing a dynamic optimization mechanism" includes:
[0013] The position and working range of the cutter in three-dimensional space are acquired in real time, and the fine processing area and far field area are defined.
[0014] The original model, complete mesh, high-precision materials, and properties are preserved in the finely processed area.
[0015] In the far-field region, the geometry is simplified, the texture resolution is reduced, blurring is applied, details are hidden, and it does not participate in real-time updates.
[0016] According to the above technical solution, preferably, in step S3, the cutting body is loaded in a dual-mode manner, including loading a physical model of the cutting body or directly generating a model of the cutting body using parameters.
[0017] According to the above technical solution, preferably, in step S3, "extracting the outer contour of the cut body" includes:
[0018] The convex hull contour is extracted using the α-shape algorithm to extract the outer contour of the cut body, forming a three-dimensional contour line;
[0019] The extracted contour lines are smoothed and saved as independent geometric data;
[0020] Move the cutting body to the position where it needs to be cut, so that it intersects correctly with the geological body.
[0021] According to the above technical solution, preferably, step S4 includes:
[0022] Boolean operations and geometric algorithms are used to detect the intersection area between the cutting body and the geological body, and all faces, edges and vertices in the geological body that intersect with the cutting body area are marked, and these data are then discarded.
[0023] The affected area is located using an octree spatial index, and a grid is reconstructed to save the dataset of the cut geological bodies.
[0024] According to the above technical solution, preferably, step S5 includes:
[0025] A pre-built octree spatial index structure is used to quickly locate target areas in geological bodies affected by cutting.
[0026] The Draco compression algorithm is used to encode and transmit the cut grid data, and to update the data of the target area in the geological body affected by the cutting.
[0027] The beneficial effects of this invention are:
[0028] This invention achieves direct updating of the original geological body through non-manifold mesh layer cutting and local mesh reconstruction, ensuring the continuity and consistency of model changes. The real-time dynamically updated three-dimensional geological model provides more accurate geological change data for dredging projects, facilitating immediate adjustment and optimization during construction, reducing rework rates, and improving construction efficiency and quality.
[0029] By utilizing LOD lightweight processing to reduce the number of faces or optimize the mesh, and by establishing a dynamic optimization mechanism using the LOD algorithm, a balance between accuracy and performance is achieved through differentiated processing of "fine processing areas" and "far-field areas". This ensures high-precision calculation and display near the cutter head while simplifying the model far from the construction area, improving software smoothness and the efficiency of dynamic model adjustment.
[0030] After completing the non-manifold cutting of the geological body and reconstructing new mesh data, only the mesh in the area affected by the cutterhead operation is processed and updated. This avoids redundant calculations in traditional global model replacement, reduces computation and transmission volume, and significantly improves the real-time performance of model dynamic adjustment and rendering. Attached Figure Description
[0031] Figure 1 This is a flowchart illustrating the dynamic cutting and updating method for non-manifold grid geological bodies provided by the present invention. Detailed Implementation
[0032] To enable those skilled in the art to better understand the technical solutions of the present invention, the present invention will be further described in detail below with reference to the accompanying drawings and preferred embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of the invention without inventive effort are within the scope of protection of the invention.
[0033] As shown in the figure, the present invention includes the following steps:
[0034] S1. Import the 3D model of the geological body and convert it to a non-manifold mesh format.
[0035] This step involves importing 3D geological models, including models created using Revit and Clivil 3D, as well as model files exported from other 3D modeling software (such as SketchUp, Rhino, Blender, etc.) (e.g., SKP, 3DM, OBJ, etc.). Then, using Assimp, the mesh is traversed to extract raw data such as vertices, faces, normals, and materials, preserving the original face connections. Material indices are mapped to custom material IDs. The 3D model is then stored in a non-manifold mesh format (vertices + normals + material IDs) for subsequent cutting, or a custom non-manifold model can be created using the Gempy modeling tool. In this example, a 3D geological model created using Rhino software is imported. The 3D geological body is divided into three layers: the upper layer of silt is brown, the middle layer of silt is blue, and the lower layer of silt is yellow. Its size is 50*50*25 meters. The model is then parsed, topologically reconstructed, and its lithological properties are mapped. The 3D model is converted into a non-manifold mesh format. The integrity of the model is checked to ensure that the geometric data, materials, textures, and other information of the model are correct, and to ensure that the model's coordinate system is consistent with that of the software.
[0036] S2. The imported 3D model of the geological body is statically simplified using LOD lightweighting, and a dynamic optimization mechanism is established using the LOD algorithm. The 3D model of the geological body at the cutterhead construction location can display the detailed process of the cutterhead excavation of the geological body, while the model at locations far from the cutterhead is blurred.
[0037] The imported model is statically simplified using LOD lightweighting to reduce the number of faces or optimize the mesh. Vertex clustering is performed, and areas with a large number of vertices in the geological body model are clustered and merged. The vertex redistribution method is used to redistribute vertices on the original model surface to change the spatial distribution density of vertices. Then, these vertices are triangulated.
[0038] Simultaneously, a dynamic optimization mechanism is established using the LOD algorithm to create dynamic levels of detail. This allows for real-time acquisition of the cutterhead's position and operating range in 3D space, defining a fine-processing region (a variable sphere centered on the cutterhead with a radius of 50 meters) and a far-field region (the region outside the variable sphere). To efficiently manage different levels of detail, the entire geological model is divided into multiple spatial blocks, each containing geological geometry and attribute data within a certain range. The original model, complete mesh, high-precision materials, and attributes are preserved in the fine-processing region. In the far-field region, geometry is simplified, texture resolution is reduced, blurred shading is applied, details are hidden, and the model is not updated in real-time. This allows the geological model to display detailed information about the cutterhead excavation process at the cutterhead's location, while blurring is applied in areas far from the cutterhead. This results in a dynamic optimization process that combines detail and smooth operation throughout the entire construction process.
[0039] S3. Load the cutting body and extract the outer contour of the cutting body.
[0040] The cutting body is loaded using a dual-mode method, including loading a physical model of the cutting body (i.e., the auger CAD model) or directly generating the cutting body model using parameters (i.e., generating the auger model using the center point, major semi-axis, minor semi-axis, etc.). In this example, the auger of a cutter suction dredger is loaded, and a 1:1 scale model is created using 3DMAX. Its shape is roughly half an ellipsoid, with a major semi-axis of 6 and a minor semi-axis of 4.
[0041] The α-shape algorithm is used to extract the convex hull contour, thereby extracting the outer contour of the cut body and forming a three-dimensional contour line. In this example, the α-shape non-convex hull algorithm is used to perform spatial topology analysis on the surface mesh of the cut body to extract its outer contour point cloud.
[0042] P_{contour}=\{p_i∈R^3|B_{α}(p_i)∩S_{cutter}≠\emptyset\}
[0043] Where: S_{cutter} is the surface mesh of the cut body, and B_{α}(p_i) is an empty sphere with radius α centered at point Pi.
[0044] The extracted contour lines are then smoothed to remove unnecessary details or noise, and saved as independent geometric data for subsequent cutting operations. In this example, during contour optimization, a curvature-based Gaussian filter is applied to P_{contour} to remove outliers with a curvature change rate > 0.15, and a smooth closed curve is generated through Catmull-Rom spline interpolation to ensure the continuity of the contour line curvature.
[0045] Based on real-time positioning data (GPS / IMU) of the construction machinery, the three-dimensional model of the cutting body is driven to move to the target cutting position so that it intersects correctly with the geological body.
[0046] S4. A non-manifold mesh layered cutting method is adopted to cut the geological body according to the real-time running trajectory of the cutting body, and the mesh data after cutting is updated.
[0047] A non-manifold mesh layered cutting method is employed. First, based on the color, material ID, and imported geological layering data of lithological silt, silt, sand, and gravel, the stratigraphic type of each geological region is marked. The optimized cut body contour line GPS positioning data is then bound in real-time; in this example, the data is the location 2 meters deep in the middle of the geological body. The cut body is then moved, and cutting operations are performed when it reaches overlapping areas. Boolean operations and geometric algorithms are used to detect the intersection areas between the cut body and the geological body. All faces, edges, and vertices in the geological body that intersect with the cut body area are marked, and these data are then discarded.
[0048] The cut area is located using an octree spatial index, and mesh reconstruction is performed while preserving the lithological boundary topology to avoid full model computation. The cut area boundaries after Boolean operations are identified to ensure local updates. Finally, these point and line data are re-interpolated, topologically connected, and reconstructed to form a new dataset of the cut geological body, which is then saved. In this example, the cut surface automatically inherits the lithological parameters of the original strata, such as RGB(150,75,0) for the silt layer, RGB(0,0,255) for the silt layer, and RGB(255,255,0) for the silt layer. The updated geological body dataset is stored in a "block LOD structure," reducing the data volume by 82% compared to full model storage.
[0049] S5. Encode and transmit the cut grid data to update the data of the target area in the geological body affected by the cutting.
[0050] After completing the non-manifold cutting of the geological body and reconstructing the new mesh data, the updated local mesh data, including attributes such as vertices, faces, normals, and material IDs, is encoded using the Draco compression algorithm and transmitted to the rendering or model framework. At this point, although the internal data has changed, the visual effects have not yet been updated synchronously. To improve efficiency, a pre-built octree spatial index structure is used to quickly locate the target area in the geological body affected by the cutting, and the mesh vertex and face data within that area are updated, avoiding a global refresh of the entire geological body model.
[0051] S6. Reconstruct and render the new geological body dataset, automatically coloring the cut surfaces according to lithology to form an updated 3D model of the geological body.
[0052] Real-time patch reconstruction is implemented based on OpenGL / Vulkan. New datasets are reconstructed and updated using lithology IDs passed through Vertex Attribute Buffers (VBOs), and dynamic coloring is performed in the fragment shader. Cut surfaces are automatically colored according to lithology (silt brown / silt blue / silt yellow), forming an updated 3D geological model that distinguishes the excavated area from the previous model, achieving dynamic cutting and updating. Automatic coloring of cut surfaces based on lithology, combined with real-time rendering updates, makes the geological changes more intuitive and smooth, facilitating real-time observation and assessment of construction results by construction personnel and supervisors.
[0053] In summary, this invention achieves direct updating of the original geological body through non-manifold mesh layer cutting and local mesh reconstruction, ensuring the continuity and consistency of model changes, realizing a real-time closed loop of the entire chain of "cutting-updating-rendering" of geological bodies in dredging projects, and providing core algorithm support for the development of intelligent dredging equipment.
[0054] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the principle of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.
Claims
1. A method for dynamic cutting and updating of non-manifold grid geological bodies based on dredging projects, characterized in that, Includes the following steps: S1. Import the 3D model of the geological body and convert it to a non-manifold mesh format; S2. The imported three-dimensional model of the geological body is statically simplified and lightweighted using LOD, and a dynamic optimization mechanism is established using the LOD algorithm. The three-dimensional model of the geological body at the cutterhead construction location can display the detailed process of the cutterhead excavation of the geological body, while the model at locations far from the cutterhead is blurred. S3. Load the cutting body and extract the outer contour of the cutting body; S4. A non-manifold mesh layered cutting method is adopted to cut the geological body according to the real-time running trajectory of the cutting body, and the mesh data after cutting is updated. S5. Encode and transmit the cut grid data to update the data of the target area in the geological body affected by the cutting; S6. Reconstruct and render the new geological body dataset, automatically coloring the cut surfaces according to lithology to form an updated 3D model of the geological body.
2. The method for dynamic cutting and updating of non-manifold grid geological bodies based on dredging engineering according to claim 1, characterized in that, In step S2, "establishing a dynamic optimization mechanism" includes: The position and working range of the cutter in three-dimensional space are acquired in real time, and the fine processing area and far field area are defined. The original model, complete mesh, high-precision materials, and properties are preserved in the finely processed area. In the far-field region, the geometry is simplified, the texture resolution is reduced, blurring is applied, details are hidden, and it does not participate in real-time updates.
3. The method for dynamic cutting and updating of non-manifold grid geological bodies based on dredging engineering according to claim 1, characterized in that, In step S3, the cutting body is loaded in two modes, including loading a physical model of the cutting body or directly generating a model of the cutting body using parameters.
4. The method for dynamic cutting and updating of non-manifold grid geological bodies based on dredging engineering according to claim 1 or 3, characterized in that, In step S3, "extracting the outer contour of the cut body" includes: The convex hull contour is extracted using the α-shape algorithm to extract the outer contour of the cut body, forming a three-dimensional contour line; The extracted contour lines are smoothed and saved as independent geometric data; Move the cutting body to the position where it needs to be cut, so that it intersects the geological body correctly.
5. The method for dynamic cutting and updating of non-manifold grid geological bodies based on dredging engineering according to claim 4, characterized in that, Step S4 includes: Boolean operations and geometric algorithms are used to detect the intersection area between the cutting body and the geological body, and all faces, edges and vertices in the geological body that intersect with the cutting body area are marked, and these data are then discarded. The affected area is located using an octree spatial index, and a grid is reconstructed to save the dataset of the cut geological bodies.
6. The method for dynamic cutting and updating of non-manifold grid geological bodies based on dredging engineering according to claim 5, characterized in that, Step S5 includes: A pre-built octree spatial index structure is used to quickly locate target areas in geological bodies affected by cutting. The Draco compression algorithm is used to encode and transmit the cut grid data, and to update the data of the target area in the geological body affected by the cutting.