Apparatus and method for 2d drawing using geometric feature analysis and interference avoidance

Abstract

The present invention relates to a two-dimensional drawing device and method using geometric feature analysis and interference avoidance. An electronic device according to one embodiment of the present invention includes a memory and a processor connected to the memory, and the processor receives 3D CAD data from a user terminal, analyzes the hierarchical structure of the 3D CAD data to identify shape information of individual parts, determines a projection method based on the shape information to generate a 2D view, extracts geometric features from the shape information to generate dimension information and tolerance information, places the dimension information and tolerance information on the 2D view to generate a manufacturing drawing for individual parts, and transmits the manufacturing drawing for individual parts to the user terminal.

Description

Technology Field

[0001] The present invention relates to a two-dimensional drawing device and method using geometric feature analysis and interference avoidance. Background Technology

[0003] Unless otherwise indicated in this specification, the contents described in this section are not prior art for the claims of this application, and are not to be recognized as prior art simply because they are included in this section.

[0004] In the modern manufacturing sector, 3D computer-aided design (3D CAD) systems are widely used during the product design stage. Using 3D CAD offers the advantage of facilitating intuitive shape identification, interference checks, and mass property calculations. However, in production sites where actual machining, assembly, and inspection take place, '2D manufacturing drawings' containing detailed information necessary for manufacturing, such as dimensions, tolerances, and surface roughness, are still essential.

[0005] Accordingly, after 3D modeling is completed, designers must perform the task of converting it back into a 2D drawing (Drafting). Conventional technologies or commercial CAD software provide the function of projecting a 2D view from a 3D model, but the following limitations exist.

[0006] First, excessive time is consumed in simple, repetitive tasks. For example, in the case of standard parts available on the market, such as bolts, nuts, and washers, even though they can be identified solely by a Bill of Materials (BOM) without separate manufacturing drawings, the batch conversion process results in inefficiency due to the execution of unnecessary drawing generation work.

[0007] Second, it is difficult to ensure the readability of the drawing by arranging elements. In order for parts to be displayed at an appropriate size within the drawing sheet according to their dimensions, the optimal scale must be calculated, and empty spaces must be found and used to place dimension lines or tolerance information so that they do not overlap with the outlines of the parts. Existing systems rely on simple rules or leave this arrangement to the manual work of designers, resulting in a significant amount of effort being invested in the post-processing stage where humans manually modify the drawings after they are generated.

[0008] Third, it is difficult to determine the projection method suitable for the characteristics of the part. When creating drawings, the criteria for selecting the first-angle or third-angle projection method may vary depending on the shape of the part, past manufacturing practices, or the requirements of the client. However, conventional systems cannot utilize historical data regarding which projection method resulted in fewer manufacturing errors when the part was drawn in the past. Consequently, there are problems where the projection method arbitrarily set by the designer causes errors in interpreting drawings on-site or leads to frequent design changes.

[0009] Therefore, there is an urgent need to develop an intelligent automatic drawing generation system that can identify the structure of 3D CAD data to eliminate unnecessary work, automate scaling and placement according to shape information, and, in particular, actively suggest the optimal projection method by analyzing past design and modification history. Prior art literature

[0011] Korean Registered Patent No. 10-0786285 (December 10, 2007) The problem to be solved

[0012] One embodiment of the present invention provides a two-dimensional drawing device and method using geometric feature analysis and interference avoidance.

[0013] The technical problems to be solved by the present invention are not limited to those mentioned above, and other technical problems not mentioned will be clearly understood by those skilled in the art to which the present invention belongs from the description below. means of solving the problem

[0015] To achieve the above-mentioned purpose, an electronic device according to one embodiment of the present invention includes a memory and a processor connected to the memory, and the processor receives 3D CAD data from a user terminal, analyzes the hierarchical structure of the 3D CAD data to identify shape information of individual parts, determines a projection method based on the shape information to generate a 2D view, extracts geometric features from the shape information to generate dimension information and tolerance information, places the dimension information and tolerance information on the 2D view to generate a manufacturing drawing for individual parts, and transmits the manufacturing drawing for individual parts to the user terminal.

[0016] At this time, the 3D CAD data is data generated using the CSG (Constructive Solid Geometry) method, and the processor can parse tree information within the hierarchical structure to extract combination information of primitives, and calculate the outer boundary and hole location of individual parts based on the combination information to identify the shape information.

[0017] At this time, the processor checks the attribute information of the individual part to determine whether the individual part is a standard purchased item, and if the individual part is determined to be a standard purchased item, it may omit the generation of the manufacturing drawing and register the individual part in the Bill of Materials (BOM) list.

[0018] At this time, when generating the two-dimensional view, the processor determines a projection method for individual parts among the first angle projection method or the third angle projection method based on a preset drawing format, and can adjust the scale of the two-dimensional view so that the two-dimensional view is included within the drawing area (Sheet) according to the projection method.

[0019] At this time, the above scale is derived by the following mathematical formula,

[0020]

[0021] S_scale refers to the scale, L_sheet refers to the maximum width in the pre-set valid area of ​​the drawing area, R_margin refers to a pre-set margin ratio constant, and L_part may refer to the maximum length of the individual part.

[0022] At this time, the processor extracts coordinate data of lines, arcs, and points included in the geometric features, calculates the Euclidean distance between the coordinate data to generate the dimension information, and if the geometric features are holes or shafts, generates the tolerance information by matching the diameter value of the geometric features with a pre-stored standard tolerance table.

[0023] At this time, the processor sets a first area occupied by the outline and internal shape line of the two-dimensional view, sets a second area corresponding to the size in which the dimension information and the tolerance information are to be displayed, searches for margin coordinates where the first area and the second area do not overlap, and places the dimension information and the tolerance information, but may place them first at a position spaced apart by a predetermined distance from the outline of the two-dimensional view.

[0024] At this time, the processor can query a drawing history database based on the identification information of the individual part to extract usage history data of projection methods previously applied to the individual part, derive a suitability score for each projection method based on the usage frequency, number of error occurrences, and time of recent use included in the usage history data, and set the projection method with the highest derived suitability score as the projection method for generating the drawing of the individual part.

[0025] At this time, the above suitability score for each method is derived by the following mathematical formula,

[0026]

[0027] S_match,i represents the above suitability score for the i-th angle method, N_i represents the number of times the i-th angle method has been applied to the corresponding individual part, E_i represents the number of times modifications occurred after application to the corresponding individual part of the i-th angle method, N_total represents the total number of times drawings have been generated for the corresponding individual part, and R_i represents the recency weight for the i-th angle method, wherein the above recency weight is derived by the following mathematical formula,

[0028]

[0029] R_i represents the aforementioned recency weight for the i-th angle method, T_current represents the current time point, T_last,i represents the time point when the i-th angle method was last used, and e may represent the natural constant. Effects of the invention

[0031] As such, according to one embodiment of the present invention, a two-dimensional drawing device and method using geometric feature analysis and interference avoidance can be provided.

[0032] The effects obtainable from the present invention are not limited to those mentioned above, and other unmentioned effects will be clearly understood by those skilled in the art from the description below. Brief explanation of the drawing

[0034] Other aspects, features, and benefits of specific preferred embodiments of the present invention, as described above, will become more apparent from the following description in conjunction with the accompanying drawings. FIG. 1 is a conceptual diagram of a two-dimensional drawing device using geometric feature analysis and interference avoidance according to one embodiment of the present invention. FIG. 2 is a block diagram of an electronic device according to one embodiment of the present invention. FIG. 3 is a drawing showing the generation of a manufacturing drawing and a parts specification list according to an embodiment of the present invention. FIG. 4 is a drawing showing a manufacturing drawing according to one embodiment of the present invention. FIG. 5 is a flowchart of a two-dimensional drawing method using geometric feature analysis and interference avoidance according to an embodiment of the present invention. It should be noted that in the drawings above, similar reference numbers are used to illustrate identical or similar elements, features, and structures. Specific details for implementing the invention

[0035] Hereinafter, embodiments of the present invention will be described in detail with reference to the attached drawings.

[0036] In describing the embodiments, technical details that are well known in the art to which the present invention belongs and are not directly related to the present invention are omitted. This is intended to convey the essence of the present invention more clearly without obscuring it by omitting unnecessary explanations.

[0037] For the same reason, some components in the attached drawings have been exaggerated, omitted, or schematically depicted. Additionally, the size of each component does not entirely reflect its actual dimensions. Identical or corresponding components in each drawing have been assigned the same reference numbers.

[0038] The advantages and features of the present invention and the methods for achieving them will become clear by referring to the embodiments described below in detail together with the accompanying drawings. However, the present invention is not limited to the embodiments disclosed below but can be implemented in various different forms. These embodiments are provided merely to ensure that the disclosure of the present invention is complete and to fully inform those skilled in the art of the scope of the invention, and the present invention is defined only by the scope of the claims. Throughout the specification, the same reference numerals refer to the same components.

[0039] At this point, it will be understood that each block of the process flow diagrams and combinations of the flow diagrams can be executed by computer program instructions. Since these computer program instructions can be loaded into the processor of a general-purpose computer, a special-purpose computer, or other programmable data processing equipment, the instructions executed through the processor of the computer or other programmable data processing equipment create means to perform the functions described in the flow diagram block(s). Since these computer program instructions can also be stored in computer-available or computer-readable memory that can be directed toward the computer or other programmable data processing equipment to implement the function in a specific way, the instructions stored in computer-available or computer-readable memory can also produce a manufactured item containing the means of instruction to perform the function described in the flow diagram block(s). Since computer program instructions can be loaded onto a computer or other programmable data processing equipment, instructions that perform a series of operation steps on the computer or other programmable data processing equipment to create a process executed by the computer can also provide steps for executing the functions described in the flowchart block(s).

[0040] Additionally, each block may represent a module, segment, or part of code containing one or more executable instructions for executing a specified logical function(s). It should also be noted that in some alternative execution examples, the functions mentioned in the blocks may occur out of order. For instance, two blocks described in succession may actually be executed substantially simultaneously, or the blocks may be executed in reverse order according to their corresponding functions.

[0041] In this embodiment, the term "part" refers to a software or hardware component such as a field-programmable gate array (FPGA) or an application-specific integrated circuit (ASIC), and the "part" performs certain roles. However, the meaning of "part" is not limited to software or hardware. The "part" may be configured to reside in an addressable storage medium or configured to run one or more processors. Accordingly, as an example, the "part" includes components such as software components, object-oriented software components, class components, and task components, as well as processes, functions, attributes, procedures, subroutines, segments of program code, drivers, firmware, microcode, circuits, data, databases, data structures, tables, arrays, and variables. The functions provided within the components and "parts" may be combined into a smaller number of components and "parts" or further separated into additional components and "parts." In addition, the components and '~parts' may be implemented to play one or more CPUs within the device or secure multimedia card.

[0042] In describing the embodiments of the present invention in detail, the primary focus will be on examples of specific systems, but the main point claimed in this specification is applicable to other communication systems and services having a similar technical background without significantly departing from the scope disclosed in this specification, and this will be possible at the judgment of a person with skilled technical knowledge in the relevant technical field.

[0043] In addition, the user terminal described below may include a communication-capable desktop computer, laptop computer, notebook, smartphone, tablet PC, mobile phone, smart watch, smart glass, e-book reader, PMP (portable multimedia player), portable game console, navigation device, digital camera, DMB (digital multimedia broadcasting) player, digital audio recorder, digital audio player, digital video recorder, digital video player, PDA (Personal Digital Assistant), etc.

[0045] FIG. 1 is a conceptual diagram of a two-dimensional drawing device using geometric feature analysis and interference avoidance according to one embodiment of the present invention, and FIG. 2 is a block diagram of an electronic device (100) according to one embodiment of the present invention.

[0046] An electronic device (100) according to one embodiment includes a processor (110) and a memory (120). The processor (110) can perform at least one of the methods described above. The memory (120) can store information related to the method described above or store a program in which the method described above is implemented. The memory (120) may be volatile memory or non-volatile memory. The memory (120) may be referred to as a 'database', 'storage unit', etc.

[0047] The processor (110) can execute a program and control the electronic device (100). The code of the program executed by the processor (110) can be stored in memory (120). The device (100) can be connected to an external device (e.g., a personal computer or a network) through an input / output device (not shown) and exchange data.

[0048] At this time, the processor (110) can receive 3D CAD data from a user terminal.

[0049] At this time, the above 3D CAD data may be data generated using the CSG (Constructive Solid Geometry) method.

[0050] The above 3D CAD data refers to digital modeling data generated through a Computer Aided Design program and includes a data structure that mathematically defines the shape, size, structure, and topology information of an object. Unlike mesh data for simple visual rendering, this contains information on the geometric attributes of the designed object and the coupling relationships between parts, making it possible to calculate precise dimensions and extract machining information.

[0051] In particular, the CSG (Constructive Solid Geometry) method used in the present invention is a modeling technique that combines predefined simple primitive shapes, such as blocks, cylinders, spheres, and cones, to represent complex three-dimensional solids.

[0052] In this case, the CSG method is characterized by defining the final shape by sequentially applying Boolean operations such as Union, Intersection, and Difference to the above basic shapes.

[0053] Data in this CSG method is stored in a logical tree structure, namely a 'CSG tree,' regarding the shape generation process. Therefore, the processor does not merely analyze the surface of the final shape; by tracing back or parsing the tree, it can identify the design intent regarding which basic shapes were used and what operations were performed by the designer.

[0054] For example, if the data includes a history of removing a cylinder shape from a cuboid shape using a set difference operation, the processor can clearly identify that the part is not a simple empty space but a 'hole' that requires machining. This serves as important basic data for automating centerline marking or tolerance notation for the part when generating 2D drawings later.

[0056] In addition, the processor can identify shape information of individual parts by analyzing the hierarchical structure of the 3D CAD data.

[0057] Looking more closely, the processor can parse tree information within the hierarchical structure to extract combination information of primitives, and based on the combination information, calculate the outer boundary and hole location of the individual parts to identify the shape information.

[0058] Specifically, the tree information within the above hierarchical structure refers to 'history' data that includes the creation order and association relationships of features generated during the part modeling process.

[0059] At this time, the processor searches sequentially or recursively from the root node to the leaf node of the tree to extract the type of primitive (e.g., hexahedron, sphere, cylinder, etc.), which is the smallest unit constituting the part, and its parameters (size, position coordinates).

[0060] In this process, the processor identifies the types of Boolean operations applied between each basic shape to specify the shape information.

[0061] For example, if a cylindrical shape is positioned on a base cuboidal shape and a 'Difference' operation is set between the two shapes, the processor identifies the area occupied by the cylinder as an empty space, i.e., a 'Hole'.

[0062] Conversely, when a 'Union' operation is applied between multiple shapes, the processor connects the outermost coordinates of the combined shapes to calculate an 'outer boundary' that determines the total size of the individual parts.

[0063] This method of analyzing the hierarchical structure has the advantage of allowing for a much clearer understanding of the internal structure or processing characteristics compared to a method that simply analyzes surface mesh information.

[0064] At this time, the processor stores the center coordinates of the identified hole or the dimension data of the outer boundary as separate metadata, and uses this as basic data to automatically generate a center line or draw an object line when creating a 2D drawing later.

[0066] In addition, the processor can generate a two-dimensional view by determining a projection method based on the shape information.

[0067] Looking more closely, when generating the two-dimensional view, the processor determines a projection method for individual parts, either a first angle projection or a third angle projection, based on a preset drawing format, and can adjust the scale of the two-dimensional view so that the two-dimensional view is included within a drawing area (sheet) according to the projection method.

[0068] At this time, the above projection method refers to orthographic projection for accurately representing a three-dimensional object on a two-dimensional plane, and can be distinguished depending on where the object is placed in space (quadrant) and projected.

[0069] Specifically, First Angle Projection is a method of positioning an object in the first quadrant (between the observer and the projection plane). In other words, it follows the principle of arrangement in the order of the observer (Eye), the object (Object), and the projection plane (Plane).

[0070] In this case, the first angle projection method is characterized by the position of the projections being drawn opposite the line of sight, such as the top view projected from the top of the object being placed below the front view and the right view projected from the right side of the object being placed to the left of the front view, based on a principle similar to casting the shadow of an object onto a back wall. This is mainly used in European standards (ISO) or architectural drawings.

[0071] In addition, Third Angle Projection is a method of placing an object in the third quadrant (the back of the projection plane). In other words, the order is observer, projection plane, and object. This is similar to placing an object inside a transparent glass box and having the observer draw the shape projected onto the glass surface (projection plane).

[0072] Therefore, the layout of the drawings aligns with the viewing direction—such as placing the top view above the front view and the right side view to the right of the front view—making it easy to intuitively grasp the shape. In the field of mechanical drafting, including Korea (KS) and the United States (ANSI), the third angle projection method is typically adopted as the standard.

[0074] In addition, second angle projection and fourth angle projection methods may theoretically exist, but they are rarely used in the creation of production drawings for actual industrial sites because they cause problems such as the plan view and the front view overlapping when the projection plane is rotated and unfolded, which reduces the clarity of the drawing.

[0075] Therefore, the processor can typically unfold a two-dimensional view based on either the first angle method or the third angle method.

[0077] In addition, the processor can extract geometric features from the shape information to generate dimension information and tolerance information.

[0078] Looking more closely, the processor extracts coordinate data of lines, arcs, and points included in the geometric features, calculates the Euclidean distance between the coordinate data to generate the dimension information, and if the geometric features are holes or shafts, generates tolerance information by matching the diameter value of the geometric features with a pre-stored standard tolerance table.

[0079] At this time, the above Euclidean distance calculation is a process of determining the actual size of a part by calculating the shortest distance between two points existing in three-dimensional space.

[0080] For example, when a dimension corresponding to the 'horizontal length' needs to be generated in a rectangular part, the processor extracts the starting point coordinates and the ending point coordinates of the corresponding edge. Then, by calculating the square root of the sum of the squares of the differences between each coordinate, which is a mathematical distance formula, the exact numerical data intended by the designer is automatically obtained.

[0081] This can be applied in the same way to curved surfaces by calculating the radius of curvature or determining the distance between the center coordinates of a circle.

[0082] In addition, the generation of the above tolerance information is an essential step to ensure the fit of the part. The processor analyzes the topological information of the three-dimensional shape and can automatically classify the cylindrical shape as a 'hole' if it is in a shape that penetrates into the part, and as a 'shaft' if it is in a shape that protrudes outward.

[0083] For example, if the identified shape is a 'hole with a diameter of 50 mm' and the system is set to apply a 'precision fit', the processor looks up the ISO standard tolerance table (or KS standard) stored in memory and searches for the tolerance value at the point where the 'reference dimension 50 mm' section and the 'hole reference fit tolerance grade H7' intersect.

[0084] As a result, a specific tolerance value of '+0.025mm (upper limit) / 0mm (lower limit)' is extracted, and this is converted into text data to be displayed alongside the previously calculated dimension information, 'Pi 50'.

[0085] This automatic matching process replaces the process of designers manually searching through standard manuals and entering data, thereby reducing drawing time and effectively preventing input errors at the source.

[0087] In addition, the processor can generate a manufacturing drawing for an individual part by placing the dimension information and the tolerance information on the two-dimensional view.

[0088] Looking more closely, the processor sets a first area occupied by the outline and internal shape line of the two-dimensional view, sets a second area corresponding to the size in which the dimension information and the tolerance information are to be displayed, searches for margin coordinates where the first area and the second area do not overlap, and places the dimension information and the tolerance information, but may place them in a position spaced apart by a predetermined distance from the outline of the two-dimensional view first.

[0089] This is a technical configuration designed to prevent an 'interference phenomenon' in which text (dimensions, tolerances) and graphics (part shapes) overlap within the generated drawing, making identification impossible. Here, the first and second areas can be defined in the form of a 'bounding box,' which is the minimum rectangular area occupied by each object.

[0090] At this time, the processor sets the coordinate range of the first area where the shape line exists as a 'Keep-out Zone' and searches for a location among the remaining 'margin coordinates' excluding this zone where dimension line extraction is easy.

[0092] In this case, instead of finding a margin randomly, an algorithm is applied to prioritize the position with the highest readability to comply with drawing standards.

[0093] For example, if the bottom outline of a specific part displayed on a 2D view is located at the Y-axis coordinate '100' and the preset offset is '10mm', the processor may first attempt to place a second area of ​​dimension text (e.g., "100 ±0.5") at the location at the Y-axis coordinate '90' (immediately below the outline).

[0094] If a collision is detected with the first area due to the presence of shape lines of other parts or other previously placed dimension information at that location, the processor abandons that location and selects a location further separated by a set distance (e.g., Y-axis coordinate '80') as a second candidate location to attempt placement again.

[0095] Through this iterative coordinate search and verification process, the final drawing produced maintains an organized state, as if it were carefully arranged by hand by the designer, and can fundamentally prevent the problem of dimension information being obscured by feature lines and misread.

[0096] In addition, the processor can transmit the manufacturing drawing for the individual component to the user terminal.

[0098] FIG. 3 is a drawing showing the generation of a manufacturing drawing and a parts specification list according to an embodiment of the present invention.

[0099] Referring to FIG. 3, the processor checks the attribute information of the individual part to determine whether the individual part is a standard purchased item, and if the individual part is determined to be a standard purchased item, it can omit the generation of the manufacturing drawing and register the individual part determined to be a standard purchased item in the Bill of Materials (BOM) list.

[0100] In this case, the attribute information refers to non-geometric metadata included in each part file separately from the 3D shape data. This may include text information such as the part number, material, vendor, description, density, and weight.

[0101] In addition, the above standard parts refer to 'ready-made products' such as bolts, nuts, washers, bearings, or motors, which are purchased from the market as standardized products rather than being processed or manufactured by the user.

[0102] In this case, since these standard purchased parts are supplied precisely manufactured according to the catalog dimensions provided by the manufacturer, there is no need to create separate detailed dimensional drawings for the production site. This is because unconditionally generating drawings for every part would result in the creation of drawings for hundreds of bolts or screws, leading to inefficiency that slows down data processing speed and wastes printing costs.

[0103] Accordingly, the processor automatically determines whether the part is a standard purchased item by checking the value of a specific field (e.g., 'Is_Purchased') within the attribute information or by analyzing, using a text matching algorithm, whether the part name includes standard specification codes such as 'ISO', 'DIN', or 'KS'.

[0104] Subsequently, parts for which drawing generation was omitted are systematically registered in the Bill of Materials (BOM) list. The aforementioned BOM refers to a document that hierarchically organizes the list, quantity, specifications, and relationships with parent assemblies of all parts constituting a product.

[0105] In this case, the processor specifies standard purchased items without drawings as 'purchased items' on the BOM, thereby supporting the purchasing department or assembly site to verify the specifications of the parts and order the exact quantity or assemble them without drawings.

[0107] FIG. 4 is a drawing showing a manufacturing drawing according to one embodiment of the present invention.

[0108] Referring to Fig. 4, the above scale can be derived by the following mathematical formula 1.

[0109] [Mathematical Formula 1]

[0110]

[0111] In this case, S_scale refers to the scale, L_sheet refers to the maximum width in the pre-set valid area of ​​the drawing area, R_margin refers to a pre-set margin ratio constant, and L_part may refer to the maximum length of the individual part.

[0112] At this time, the above mathematical formula 1 represents the process of calculating the optimal scale at which a part is drawn by simultaneously considering the physical limits of the drawing area (sheet) and the drawing standard.

[0113] Specifically, the numerator of the above mathematical formula has an operation structure that multiplies the remaining ratio after subtracting a preset margin ratio from the total length of the drawing area. This signifies defining the size of the 'actually effective usable area' where the shape of the part can actually be drawn, excluding the margin that must be secured around the drawing's borders.

[0114] In other words, the higher the margin ratio constant is set, the narrower the effective area is calculated and the more the drawing is gathered inward, whereas conversely, the lower the constant is set, the wider the effective area is secured.

[0115] Furthermore, the denominator of the above mathematical formula represents the maximum length of the inherent shape of the part. Consequently, the processor derives the ratio value to which the part must be maximally enlarged or reduced within the range where it does not encroach upon the margins by dividing the 'size of the effective available area' by the 'actual size of the part'.

[0116] Drawings generated through this computational structure fundamentally prevent errors where parts extend outside the sheet area, while simultaneously resolving the problem of parts being drawn too small, which makes shape identification difficult, thereby providing optimal readability.

[0117] For example, if a user sets a drawing area corresponding to the size of A3 paper, the maximum width length (L_sheet) of the drawing area is '400mm', and the margin ratio constant (R_margin) set by the system administrator is '0.1 (i.e., 10%)', the processor first excludes 40mm, which is 10% of the total width of 400mm, and calculates '360mm', which is the remaining 90%, as the valid area where parts can be drawn.

[0118] If the actual maximum length (L_part) of an individual part to be drawn is '180mm', the processor performs a calculation to divide the previously calculated valid area '360mm' by the actual length of the part '180mm'. The resulting value is '2', which means that when the part is drawn enlarged to twice its actual size, it will fill the valid area of ​​the drawing exactly.

[0119] Therefore, the above processor automatically sets the scale (S_scale) of the drawing to '2:1 (extended)' to create a 2D view.

[0120] Conversely, if the actual length of the part is very large, such as '720mm', under the same conditions (effective area 360mm), the result of the division operation becomes '0.5'. In this case, the processor sets the scale to '1:2 (scale)' and reduces the shape of the part to half its size so that it does not go beyond the drawing area.

[0121] This example demonstrates that the above mathematical formula actively finds the optimal ratio that always adheres to the drawing specifications, regardless of the size of the part.

[0123] In addition, the processor can query a drawing history database based on the identification information of the individual part to extract usage history data of projection methods previously applied to the individual part, derive a suitability score for each projection method based on the usage frequency, number of errors, and time of recent use included in the usage history data, and set the projection method with the highest derived suitability score as the projection method for generating the drawing of the individual part.

[0124] The reason such a configuration is necessary is that even if the same three-dimensional shape is represented in first angle projection or third angle projection, the intuitive understanding of the worker interpreting the drawing may differ.

[0125] In particular, for certain parts, due to the complexity of their shapes, there is a tendency for on-site misinterpretation or machining errors to occur frequently when specific carving methods are applied.

[0126] Therefore, the present invention does not simply rely on fixed option values, but analyzes past success and failure data to reflect it in decision-making. That is, projection methods with a high number of modifications or error frequencies in the past are automatically excluded by receiving deductions in the suitability score, while methods that have been used repeatedly without issues until recently receive high scores and are preferentially adopted.

[0127] This allows the most optimized and verified projection method for the part to be automatically applied without the designer having to think about it every time, thereby ensuring the reliability of the drawing and providing the effect of significantly reducing the defect rate during the manufacturing stage.

[0128] To examine this more specifically, the above fit score for each method can be derived by the following mathematical formula 2.

[0129] [Mathematical Formula 2]

[0130]

[0131] In this case, S_match,i represents the above suitability score for the i-th angle method, N_i represents the number of times the i-th angle method has been applied to the corresponding individual part, E_i represents the number of times modifications occurred after application to the corresponding individual part of the i-th angle method, N_total represents the total number of times drawings have been generated for the corresponding individual part, and R_i may represent the recency weight for the i-th angle method.

[0132] In addition, the above recency weight can be derived by the following mathematical formula 3.

[0133] [Mathematical Formula 3]

[0134]

[0135] In this case, R_i represents the recency weight for the i-th angle method, T_current represents the current time point, T_last,i represents the time point when the i-th angle method was last used, and e may represent the natural constant.

[0136] At this time, the above mathematical formulas 2 and 3 are algorithms designed to make optimal decisions by combining two variables, 'success probability' and 'latestness,' moving away from a one-dimensional method of simply selecting the most frequently used method.

[0137] Specifically, looking at the structure of mathematical formula 2, the numerator (N_i - E_i) is the value obtained by subtracting the number of errors (corrections) from the total number of applications, which represents the 'pure number of times each method was successfully applied without failure'.

[0138] Dividing this by the total number of drawings generated for the corresponding part (N_total) is intended to calculate the 'success share' that each method occupies within the total history.

[0139] In other words, each method that had frequent errors is designed so that even if the share is high, the (N_i - E_i) value becomes small and the fit score is calculated low.

[0140] In addition, Equation 3 defines the decrease in weight over time. The reason for applying the natural logarithm (ln) function to the denominator here is to smoothly adjust the rate of score decline over time.

[0141] If the data is divided simply by the time difference without a logarithmic function, a distortion may occur where the score drops sharply after just one day. The present invention combines a logarithmic function and a natural constant (e) so that when used most recently (T_current-T_last= 0), the denominator becomes ln(e)=1, maintaining the weight at its maximum value (1), and the weight gradually decreases as time passes, thereby rationally reflecting the latest trend of the data.

[0142] For example, regarding a specific part A, the 'first angle method' was used 100 times over the past 10 years but not in the last 3 years (low R_i), while the 'third angle method' was used intensively 50 times in the last 1 year with almost no errors (high R_i, high success rate). In this case, the first angle method (100 times) is dominant in terms of simple cumulative count, but when the above mathematical formula is applied, the third angle method is assigned a high recency weight (R_i) and overtakes the first angle method in the final fit score (S_match).

[0143] As a result, the above processor sets the 'third angle projection method' as the final projection method, reflecting current quality stability and trends rather than past practices, which can provide the effect of generating drawings that match field trends.

[0145] FIG. 5 is a flowchart of a two-dimensional drawing method using geometric feature analysis and interference avoidance according to an embodiment of the present invention.

[0146] Referring to FIG. 5, a two-dimensional drawing method using geometric feature analysis and interference avoidance according to one embodiment of the present invention can receive three-dimensional CAD data from a user terminal (S101).

[0147] In addition, a two-dimensional drawing method using geometric feature analysis and interference avoidance according to one embodiment of the present invention can identify shape information of individual parts by analyzing the hierarchical structure of the three-dimensional CAD data (S103).

[0148] In addition, the two-dimensional drawing method using geometric feature analysis and interference avoidance according to one embodiment of the present invention can generate a two-dimensional view by determining a projection method based on the shape information (S105).

[0149] In addition, a two-dimensional drawing method using geometric feature analysis and interference avoidance according to one embodiment of the present invention can generate dimension information and tolerance information by extracting geometric features from the shape information (S107).

[0150] In addition, a two-dimensional drawing method using geometric feature analysis and interference avoidance according to one embodiment of the present invention can generate a manufacturing drawing for an individual part by placing the dimension information and the tolerance information on the two-dimensional view (S109).

[0151] In addition, the two-dimensional drawing method using geometric feature analysis and interference avoidance according to one embodiment of the present invention can transmit the manufacturing drawing for the individual part to the user terminal (S111).

[0152] In addition, a two-dimensional drawing method using geometric feature analysis and interference avoidance according to one embodiment of the present invention can be configured in the same way as a two-dimensional drawing device using geometric feature analysis and interference avoidance disclosed in FIGS. 1 to 4.

[0154] The embodiments described above may be implemented as hardware components, software components, and / or combinations of hardware and software components. For example, the devices, methods, and components described in the embodiments may be implemented using one or more general-purpose or special-purpose computers, such as, for example, a processor, a controller, an arithmetic logic unit (ALU), a digital signal processor, a microcomputer, a field programmable gate array (FPGA), a programmable logic unit (PLU), a microprocessor, or any other device capable of executing and responding to instructions. The processing unit may execute an operating system (OS) and one or more software applications executed on said operating system. Additionally, the processing unit may access, store, manipulate, process, and generate data in response to the execution of the software. For ease of understanding, the processing unit may be described as being used as a single unit, but those skilled in the art will understand that the processing unit may include multiple processing elements and / or multiple types of processing elements. For example, the processing unit may include multiple processors or one processor and one controller. Additionally, other processing configurations, such as parallel processors, are also possible.

[0155] The method according to the embodiment may be implemented in the form of program instructions that can be executed through various computer means and recorded on a computer-readable medium. The computer-readable medium may include program instructions, data files, data structures, etc., either alone or in combination. The program instructions recorded on the medium may be those specifically designed and configured for the embodiment, or they may be those known and available to those skilled in the art of computer software. Examples of computer-readable recording media include magnetic media such as hard disks, floppy disks, and magnetic tapes; optical recording media such as CD-ROMs and DVDs; magneto-optical media such as floptical disks; and hardware devices specifically configured to store and execute program instructions, such as ROM, RAM, and flash memory. Examples of program instructions include machine code, such as that generated by a compiler, as well as high-level language code that can be executed by a computer using an interpreter, etc. The hardware devices described above may be configured to operate as one or more software modules to perform the operation of the embodiment, and vice versa.

[0156] Software may include computer programs, code, instructions, or a combination of one or more of these, and may configure a processing unit to operate as desired or command the processing unit independently or collectively. Software and / or data may be permanently or temporarily embodied in any type of machine, component, physical device, virtual equipment, computer storage medium or device, or transmitted signal wave so as to be interpreted by the processing unit or to provide instructions or data to the processing unit. Software may be distributed over networked computer systems and may be stored or executed in a distributed manner. Software and data may be stored on one or more computer-readable recording media.

[0157] Although the embodiments have been described above with reference to the limited drawings, those skilled in the art can apply various technical modifications and variations based on the above. For example, suitable results may be achieved even if the described techniques are performed in a different order than described, and / or if the components of the described system, structure, device, circuit, etc. are combined or assembled in a form different from described, or replaced or substituted by other components or equivalents.

[0158] Therefore, other implementations, other embodiments, and equivalents to the claims also fall within the scope of the claims set forth below.

Claims

Claim 1 In an electronic device, memory; and a processor connected to said memory; The processor comprises: receiving 3D CAD data from a user terminal, analyzing the hierarchical structure of the 3D CAD data to identify shape information of individual parts, determining a projection method based on the shape information to generate a 2D view, extracting geometric features from the shape information to generate dimension information and tolerance information, placing the dimension information and tolerance information on the 2D view to generate a manufacturing drawing for individual parts, and transmitting the manufacturing drawing for individual parts to the user terminal; wherein the 3D CAD data is data generated using the CSG (Constructive Solid Geometry) method; wherein the processor parses tree information within the hierarchical structure to extract combination information of primitives, calculates the outer boundary and hole location of individual parts based on the combination information to identify the shape information; wherein the processor checks the attribute information of individual parts to determine whether the individual parts are standard purchased parts, and if the individual parts are determined to be standard purchased parts, the The generation of production drawings is omitted, and the individual part determined to be a standard purchased item is registered in the Bill of Materials (BOM) list; and when generating the 2D view, the processor determines the projection method for the individual part among the first angle projection or the third angle projection based on a preset drawing format, and adjusts the scale of the 2D view so that the 2D view is contained within a drawing area (sheet) according to the projection method, wherein the scale is derived by the following mathematical formula, S_scale refers to the scale, L_sheet refers to the maximum width in the valid area pre-set in the drawing area, R_margin refers to a pre-set margin ratio constant, and L_part refers to the maximum length of the individual part; the processor extracts coordinate data of lines, arcs, and points included in the geometric features, calculates the Euclidean distance between the coordinate data to generate the dimension information, and if the geometric feature is a hole or a shaft, generates the tolerance information by matching the diameter value of the geometric feature with a pre-stored Standard Tolerance Table, and the processor sets a first area occupied by the outline and internal shape lines of the 2D view, sets a second area corresponding to the size in which the dimension information and the tolerance information are to be displayed, searches for margin coordinates where the first area and the second area do not overlap to place the dimension information and the tolerance information, wherein the 2D A position spaced apart by a preset distance from the outline of the view is prioritized and placed, and the processor queries a drawing history database based on the identification information of the individual part to extract usage history data of projection methods previously applied to the individual part, derives a suitability score for each projection method based on the usage frequency, number of errors, and time of recent use included in the usage history data, sets the projection method with the highest derived suitability score as the projection method for generating the drawing of the individual part, and the suitability score for the corresponding projection method is derived by the following mathematical formula, S_match,i represents the above suitability score for the i-th angle method, N_i represents the number of times the i-th angle method has been applied to the corresponding individual part, E_i represents the number of times modifications occurred after application to the corresponding individual part of the i-th angle method, N_total represents the total number of times drawings have been generated for the corresponding individual part, and R_i represents the recency weight for the i-th angle method, wherein the above recency weight is derived by the following mathematical formula, R_i represents the latest weight for the i-th angle method, T_current represents the current time point, T_last,i represents the time point when the i-th angle method was last used, e represents the natural constant, and the above-mentioned parts specification list includes a document in which the list, quantity, specifications, and relationship with the parent assembly of all parts are hierarchically organized, and the above-mentioned standard purchased items are indicated by being specified as 'purchased items', characterized by an electronic device.

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