3D complex design modeling technique using horizontal copy method with linear slope

Abstract

A technology that allows designers to easily generate complex 3D site design models by combining simple commands. The Offset command obtains 3D information by extending a linear line in the left and right horizontal directions to an arbitrary distance in 2D CAD design. In site design, by drawing inspiration from the concept of applying a 2% gradient in the road cross-section direction and rock-line slope in slope design, you can easily create objects using the Slope Direction Offset function and clean them up with Trim and Fillet commands to quickly generate 3D models for site design.

Description

Technology Field

[0001] The present invention relates to the fields of urban design and architectural design using a computer-based CAD (Computer-Aided Design) system, and more specifically, to a 3D urban design modeling technique that easily generates 3D modeling information based on 2D CAD design data and converts it into an urban design BIM (Building Information Modeling) model. It relates to a method for rapidly modeling complex site design models through a simple process. Background Technology

[0003] In the past, in the field of civil engineering and architecture design, buildings were constructed using the creative abilities of craftsmen with rudimentary designs created by drawing rough three-dimensional shapes and indicating only simple dimensions. However, as society gradually developed, complex structures were projected into two dimensions and expressed through various drawings such as plan, view, side view, and detail view.

[0005] However, due to the complex follow-up tasks arising from reviewing various drawing information for quantity surveying, construction, and maintenance, the system is shifting toward BIM modeling—which incorporates various design information into a single 3D model—where design is performed collectively and information entered once is utilized multiple times across diverse fields, such as quantity surveying, analysis through various simulations, construction, and maintenance.

[0007] In addition, there is a concept of providing drawing composition by projecting only the relevant part from a 3D BIM model into 2D in cases where it is difficult to communicate complex 3D shapes. As the importance of BIM grows, the need for 3D design is emerging as the government has mandated and legalized BIM design to lead the international market (Ministry of Land, Infrastructure and Transport Notification No. 2019.02.25., Review Standards for Large-Scale Construction Projects, etc.).

[0009] However, BIM is leading the way in the architectural field, where lines and surfaces can be easily represented. In the civil engineering design field, road design techniques that allow for easy road modeling by projecting cross-sections along the road centerline have been relatively advanced, and BIM design is becoming more active as the number of varying road cross-sections within a single construction section is limited to only a few dozen.

[0011] In the field of urban design, BIM design is currently being implemented by modeling road cross-sections by projecting them onto the road centerline. However, because there are significant variations such as bus stops, entrance and exit ramps, and curves at intersections, and because thousands of roads exist within a single complex, 3D complex design modeling is difficult, the application of BIM is not being widely adopted. Furthermore, the difficulty of its usage and the lack of BIM technicians, despite government-led measures to promote BIM, are major problems.

[0013] To solve these problems, the present invention proposes a technology that enhances the designer's visibility and allows for the easy creation of complex 3D complex design models by combining simple commands.

[0015] The Offset command extends a linear line in 2D CAD design to an arbitrary distance in the left and right horizontal directions.

[0017] In site design, you can quickly generate 3D models for site design by taking inspiration from the concept of giving a 2% slope in the cross-sectional direction of roads and the concept of giving a slope in the direction of rock selection in slope design, easily creating objects using the slope direction Offset function, and cleaning them up with Trim and Fillet commands. The problem to be solved

[0019] The purpose is to provide a system and design method that utilizes 2D CAD design concepts while providing the 3D spatial concepts required by BIM, enabling existing 2D designers to create BIM models without separate retraining.

[0021] The existing civil engineering design method, the two-dimensional road cross-section extension method, is used, and since many cross-section processing tasks and design information values ​​are stored only within BIM objects, readability is poor. Furthermore, because the closed Digital Terrain Modelling (DTM) engines of foreign packages do not meet domestic design standards, 2D-based design is performed in parallel with BIM design, making the application of BIM an inevitable heavy burden for design firms.

[0023] Road design programs have about 20 sections where the road width changes over a 3-5 km section, so there is little work to change the dimensions of the standard cross-section above. However, when applied to complex design, the standard cross-sections (61) of Fig. 7 are changed at each red solid line inflection point (63) of the plan drawing (62) above, and the complex design can be applied using a modeling technique that connects adjacent cross-sections for each structure into a single work section. However, the curved section (64) with the yellow circle has dimensions that change continuously, making it impossible to apply the cross-section method. Therefore, it is separated into a separate corridor zone for design, and since there are thousands of such roads within one development district, work must be done by separating the curved section design area into three times the number of road sections.

[0025] Although the workload for site design is hundreds of times greater than that for road design, domestic design standards such as compaction and stage treatment do not apply. Therefore, while a separate program is used to read the drawing information from the BIM design system's output to support design that meets domestic standards, this method is not being widely adopted because the package changes with annual upgrades, resulting in only auxiliary work rather than technological advancement. means of solving the problem

[0027] The present invention proposes a method for generating 3D complex models by easily developing various offset functions with slopes for 3D lines using the concept of the offset function, which horizontally copies 2D lines among existing familiar CAD commands, and enables working with curved and straight sections as a single section.

[0029] 3D offset is a function that copies a new 3D alignment to the left or right of a 3D alignment while maintaining a constant distance or change distance. This allows you to expand the cross-sections of various structures or accurately represent the edge lines of road slopes.

[0031] 3D Offset is used in combination with 3D Fillet (semicircling intersecting lines) and 3D Chamfer (chamfering intersecting lines), and allows for the generation of complex 3D linear coordinate points without calculation, using only the slope direction and offset distance. For example, the 3D linear Fillet function can be utilized to smooth curves for intersections. Here, the 3D Offset function converts the 3D linear line into a linear line where the height of each point changes, incorporating straight lines, circular curves, 3D functions capable of mitigating the transition between straight and circular curves, or various curves such as clothoid curves or logarithms.

[0033] This method is a widely used approach in conventional 2D CAD that creates drawings by accurately generating and organizing alignments without precise coordinate calculations, provided that only the wall thickness and road width specifications are known. It is a function of the Surface Modeling technique, which involves drafting 3D alignments of the model's boundaries using commands of almost the same system in situations where BIM design engineers are scarce, and allowing the DTM engine to process these alignments into faces for 3D modeling.

[0035] The modeling technique used in machinery utilizes the Solid Modeling concept, which implies that an object is filled to the core. While it excels in creating complex shapes and reviewing overlaps using object union and difference functions, the civil engineering and architecture fields, which model urban bodies, generate a large volume of information. Therefore, to minimize model size, Surface Modeling techniques that model only the surface are used. By generating the edge lines of complex shapes using the proposed technique, 3D Surface Modeling is easily created. Furthermore, by simply inputting the longitudinal and transverse alignments of the model, various estimation and analysis information is provided, and a VR (Virtual Reality) simulation model of the entire model is offered.

[0037] The complex design modeling technique proposed as a BIM design method for the road section within the complex is as shown in FIG. 2, in which the road design centerline (11) is offset as a 3D line to the L-shaped side ditch line (12), and the bus stop (14), entrance / exit widening section, and road intersection alignment are additionally offset as 3D lines, then added or subtracted using 3D Fillet and 3D Chamfer, and the alignment is combined into one using the 3D alignment Join function.

[0039] The road design during the complex design is completed by using the 3D multi-offset function to create the completed L-shaped side ditch line, road curb, sidewalk (15), and sidewalk curb. Additionally, the median strip (flower bed in the center of the road) can also be created using the same concept.

[0041] The 3D Offset function also allows for varying the offset distance in certain sections depending on design conditions, such as widening sections of the road, rather than just offsetting by applying a slope over a certain distance.

[0043] As shown in Fig. 3, the BIM design method for the complex area involves a function that uses the complex boundary line generated in the road design to design the slope of the complex area. To ensure smooth drainage of rainwater from the complex area, a plan with a slope of 2% in a certain direction must be created, and a 3D slope line with a slope of 1:1.5 with respect to the complex boundary line is created.

[0045] The function for designing the slopes of outer roads using the outer slope BIM design method includes retaining wall design and consists of a function that offsets multi-layered 3D slope lines according to berms, rock layers, and slopes at regular intervals. If a retaining wall is required at the road boundary, this function drafts the retaining wall line and generates a cross-sectional line using the normals based on the road end line and retaining wall line coordinates. It then constructs cross-sections according to slopes that meet slope design standards, creating a shape in the form of a 3D offset of the boundary alignment of each slope.

[0047] The development features include the following functions.

[0048] - 3D slope offset function: A function that offsets by applying a 3D linear slope.

[0049] - 3D Fillet: A function that performs a forced fillet by interpolating two linear planes instead of a single plane in space.

[0050] - 3D Chamfer: A function that forcibly chams by interpolating two linear planes instead of a single plane in space.

[0051] - 3D Polyline Join: The joining of 3D polylines where their endpoints meet.

[0052] - 3D Multi-Linear Slope Offset Function: A function that offsets by applying multiple 3D linear slopes.

[0053] - Design of Slope Plan for Block Complex: Generate a closed 3D linear plane, a plane with a slope at an arbitrary height, and an edge line which is a 3D slope line with a 1:1.5 slope (refer to the figure above).

[0054] - 3D Cutting Surface Design by Rock Layer: Draft edge lines reflecting berms based on the slope of each rock layer, considering the retaining wall line in the 3D alignment.

[0056] ※ Offset, Fillet, and Chamfer are identical to 2D CAD functions, except for the consideration of slopes. Effects of the invention

[0058] Improved work efficiency:

[0059] Compared to other civil engineering design fields, the application of BIM in site design has a limited track record, and finding skilled technicians is difficult due to the complexity of its usage. This proposed method is identical to the command system used in current 2D CAD, differing only in that it is 2D versus 3D. By simply adding site slope conditions, the workflow remains the same, allowing shapes to be generated immediately for better readability. Furthermore, by automatically calculating coordinates that account for slopes to draft alignments, work time is dramatically reduced. Unlike existing 3D civil engineering design system packages that store object attribute information only internally, this method displays 3D alignments at every stage, making it easier to design complex shapes.

[0061] Accurate site modeling is possible by simplifying the design of internal roads, blocks, and outer slopes into simple patterns. Furthermore, the work time required for site modeling using foreign packages is incomparable; work can be completed faster than conventional 2D plan design, and since all 3D information is integrated, it enables automatic quantity calculation and various simulation tasks. A significant advantage is that the DTM engine was developed using domestic technology, allowing it to be tailored to the domestic design environment; unlike foreign packages, the results can be used as detailed design drawings without the need for separate detailed design work.

[0063] The system developed using the proposed method was used for site analysis in Sejong City, expanding the development area from approximately 20 million pyeong to 22 million pyeong, and was also applied to the analysis of earthwork volume for the relocation project of the US military base in Pyeongtaek, contributing to cost savings of approximately 300 billion won.

[0065] Although this technique was developed as a doctoral dissertation topic in the 1990s, it could not be utilized because domestic clients developed 2D design systems, provided them for free, and mandated their use. It was applied only to the development of Sejong City and the relocation of US military bases through private requests for confidential security projects.

[0067] Recently, the government has been encouraging the application of BIM due to the demand for BIM usability when entering overseas construction projects and the advancement of construction technology. However, as it has not been utilized for over 10 years, the government is now supporting the use of BIM by making it mandatory. Brief explanation of the drawing

[0070] Figure 1 shows the screen of a 3D site design modeling CAD extension program. Figure 2 shows the method of securing 3D spatial information by offset based on the road centerline. Fig. 3 is a 3D view securing a road slope with a 2% incline. Fig. 4 shows the screen for creating a DTM model in 3D linear form. Figure 5 shows the detailed view of the site design model (slopes within the site, road curb stones, etc.) and the site design menu function. Figure 6 shows the cross-sectional view output and detailed design. Figure 7 shows the road cross-section and plan view, and the reasons why the cross-section method cannot be applied. Fig. 8 shows a linear generation method for horizontal movement of the centerline. Figure 9 shows the cross-sectional design screen Figure 10 is BIM analysis of the planned new city site (created directly using this program) Specific details for implementing the invention

[0071] *. 3D Offset, Chamfer, and Fillet functions

[0072] Among the developed features, the Offset function is a linear offset involving multiple points; therefore, if the spacing between points is narrow relative to the offset distance, the points become tangled. While perfectly handling all cases would require a very complex function, to make it easier, it was developed as a feature that stores the height values ​​of 3D points, draws a 2D line excluding the height values, offsets the line using CAD functions, reads the coordinates of those points, and assigns the height of the point closest to the original line. The Multi-Linear Offset is also a function that combines the same functionality as the 3D Offset function multiple times.

[0074] Fillet and Chamfer are similar concepts; rather than focusing on development difficulty, a shift in perspective allows for the use of 3D Offset, Fillet, Multiple 3D Offset, and 3D Linear Join functions instead of the road cross-section setting functions found in foreign packages. This significantly enhances the user's visualization of 3D terrain space and offers great effectiveness due to its similarity to existing usage methods. Furthermore, it offers significant time savings by simply setting thousands of road cross-sections in a complex—a collection of many roads—on a flat plane using conventional methods.

[0076] As an auxiliary function, it allows writing height values ​​to a specific 3D linear layer, so that when viewed from the top view, it is a 2D drawing, but by referencing the height values, it enhances the understanding of 3D spatial information and provides a function to delete the height value text of the corresponding layer all at once when the work is finished.

[0078] Second auxiliary function provides a feature that offers real-time elevation values ​​and cross-sections for the terrain and underground rock layers of the desired point.

[0080] *. Complex Floor Plan Design Function

[0081] As shown in Fig. 8, to facilitate the smooth drainage of rainwater, a slope (72) of 2% is applied based on a certain height of the inner center point (71), and each line segment of the lines where the outer boundary and the corresponding plane meet is projected at a normal direction with a slope of 1:1.5 (73) to create a continuous line of meeting points.

[0083] *. Slope generation function of the outer boundary

[0084] This function creates an external terrain and boundary slope on the outer boundary line as shown in Fig. 9. It reads the cross-terrain (81) from the DTM to the rock layer information for each line within each linear line at a certain distance in the normal direction, and obtains a continuous slope line (83) by reflecting the small steps every 5m and finding the points that meet the original ground line according to the slope design standard (82) for each rock layer.

[0086] 3D modeling the designed edge line using a DTM engine

[0087] As shown in Fig. 6, when information on the planned terrain and various structures is input as a 3D linear shape, the DTM engine reads it and performs surface modeling, and 3D model analysis is possible, allowing the cross-section of an arbitrary point to be checked and output in real time to calculate the quantity of earthwork and structures.

[0089] 3D design integrates various design information into three dimensions and supports the designer's judgment in various ways, displaying the 3D model from various angles along with various analysis functions as shown in Fig. 6.

[0091] *. Design time comparison

[0092] In the past, designing a 200,000-pyeong complex required a team of five people and took one month under manual methods; however, with the development of 2D design systems, it now takes one week for a single person. On the other hand, a complex design system utilizing 3D Offset, while similar in usage to 2D systems, takes only one day. It supports various analyses and quantity calculations, providing an environment where designers can dedicate their time to improving design quality rather than performing countless simple numerical calculations. Although foreign civil engineering design packages take one month, direct time comparisons are difficult because domestic design standards differ; these packages are used only for planning design, while detailed design is carried out in parallel using 2D systems.

[0094] *. Current Status of Domestic Civil Engineering BIM Design System Usage and CDS-3D Usability

[0095] The CDS-3D system, created using the proposed design technique, is a competitor to Autodesk’s Civil 3D. It was developed as an early prototype in the late 1980s because using Inroads was inconvenient. Among the product lines of this company (Microsoft), InSite is intended for site design. Although Inroads is recommended for complex designs due to its simple functionality, the concept of projecting road cross-sections onto road alignments is not suitable for site design and requires a lot of work time, so it is not widely used for site design work.

[0097] Civil 3D is similar to Inroads and has established itself as a basic software required for BIM, alongside Revit. Among domestically developed 3D complex design software, Namosoft developed a similar design method using road crossings.

[0099] Whether using foreign packages or domestic complex design programs, when considering only the various analysis functions, the most important factor for easily performing 3D complex design modeling is a technique that can drastically reduce work time. The feasibility of detailed design is also important, and it must comply with domestic design standards; however, foreign packages are used only for analysis purposes because they do not account for the handling of earthwork volumes or road compaction volumes.

[0101] Due to the closed nature of foreign packages, it is impossible to incorporate domestic design standards. Consequently, while there are some instances where output results are read and used for cost estimation on a limited basis for specific tasks, detailed design is generally conducted separately. Since current BIM guidelines require the direct calculation of quantities from BIM objects, this method is frequently used when utilizing foreign packages.

[0103] Ultimately, in order to avoid dependence on the DTM engine, which is a basic function of foreign civil engineering BIM packages, CDS-3D developed a DTM engine using domestic technology, enabling the addition of attribute information at the engine level and acquiring the ability to expand development capabilities in accordance with domestic design standards.

[0105] Although most domestic civil engineering design programs have DTM engines, they do not consider line elements (calculating so that specific lines do not intersect to form a surface), so they are used for processing flat terrain or rock lines. However, the DTM engine of the CDS-3D system considers line elements, so there are no broken representations of accurate retaining walls, slopes, or curb stones, and processing times are relatively fast because it databases area separation based on the number of points. As shown in Figure 10, during the site analysis for the development of Sejong City, the terrain analysis of a 200 million pyeong map with 2 million points was processed in the one-hour range.

[0107] Although it is a minor idea, if foreign civil engineering BIM design packages reference this feature and add development capabilities, emphasizing their immense capital and interoperability with supporting software, domestic programs will be unable to survive, and the cost of purchasing foreign software will increase significantly.

[0109] Previously, the lifetime price of AutoCAD was 2.5 million won, but currently, an annual usage fee of 2.5 million won is charged. Furthermore, the cost of basic BIM software such as Revit, Navisworks, and InfraWorks alone amounts to around 10 million won per designer annually, raising concerns about significant national wealth loss.

[0111] This proposed feature can be used for all designs requiring precise topographical representation, such as apartment design, detached house design, dams, and roads, making the utility of this technology very high. Explanation of the symbols

[0113] 1 : CAD extension 2 : Road line Offset 3 : Block slope Offset 4 : Bevel line Offset 11: Road Centerline Design 12: Offset L-shaped side gutter 13 : whole angle 14: Bus Stop Design 15: Sidewalk Line Design 16: Slope. Retaining Wall Line Design 21 : Ground line 22 : Slope 61 : Cross-section drawing 62 : Floor plan 63 : Section size change point 64: Areas where cross-sectional projection is not applicable 71 : Centerline 72 : 2% horizontal shift linear 73 : 1:1.5 Gradient Horizontal Translation Linear 81: Cross-sectional design for every linear segment 82 : Design Standards for Slope by Rock Layer 83: Normal slope design and continuous line for each boundary segment

Claims

Claim 1 A 3D design technique that secures 3D spatial information through 3D offset movement using a 2D design method. Claim 2 BIM design method for road sections within a complex according to Claim 1 Claim 3 In claim 1, the outer slope BIM design method Claim 4 Method for applying 3D Offset, Chamfer, and Fillet according to Claim 1 Claim 5 In claim 1, the method for designing the floor plan of the complex section

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