JPH04276865A - Method for forming three-dimensional model - Google Patents

Abstract

PURPOSE:To build up a three-dimensional model easily by connecting between projected lines as viewed from the arrow head with surface plates. CONSTITUTION:Toward solids 70 and 72, lines 74a and 74b are projected from different directions of view, line 74 that the projected lines 74a and 74b intersect and line 76 that projected lines 76a and 76b intersect are connected using surface plates 80, while an edge line of solid 70 and line 74 are connected using surface plate 78, and further surface plate 82 is used to connect between an edge line of solid 72 and line 76.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for creating a three-dimensional model in a computer-aided design system (hereinafter referred to as a CAD system).

0002

2. Description of the Related Art Conventionally, when creating a three-dimensional model in a CAD system, a surface is created by viewing the three-dimensional model from a plurality of arrow directions, determining their intersection points or lines, and combining them. However, when determining intersections or lines, multiple lines (or points) are mixed together, making it difficult to grasp the shape, and since a three-dimensional model is retained as edge line data, a large amount of design man-hours is required. there was.

0003

[Problems to be Solved by the Invention] The present invention has been made in order to reduce a great deal of labor when creating a three-dimensional model, and it involves projecting a plurality of lines onto a three-dimensional model from the direction of the arrow.
It is an object of the present invention to provide a method for creating a three-dimensional model that can easily create a three-dimensional model by connecting the lines with surfaces.

0004

[Means for Solving the Problems] In order to solve the above problems, the present invention provides a method for creating a three-dimensional model using a CAD system, in which an outline shape is defined by inputting shape numerical values of a reference three-dimensional model. , a three-dimensional model having a desired shape is created by connecting at least two lines projected from the arrow direction to the three-dimensional model with a surface.

[0005]

[Operation] According to the present invention, by connecting two lines projected from the arrow direction to the three-dimensional model with a surface,
Three-dimensional models can be easily constructed without making changes to individual lines.

[0006]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The method for creating a three-dimensional model according to the present invention will be described in detail below with reference to the accompanying drawings, with reference to preferred embodiments in relation to an apparatus incorporating the method.

The CAD system to which this embodiment is applied is as follows:
It is configured as shown in FIG. In other words, this CAD system has a central processing unit that performs graphical calculations, display control,
A computer 2 that plays a role such as database management, a mass storage device 4 that can store and update a large amount of graphic information, a graphic output device 6 such as an XY plotter, and a central device for interaction between the CAD system and its user. It is comprised of a plurality of graphic display devices 8 that are used in conjunction with input devices, and devices such as a tablet 10, a keyboard 12, a mouse 14, and a light pen 16 that are connected to each graphic display device 8.

The CAD system has many programs, as shown in FIG. Each program can be classified into the following modules depending on the functions they share. (a) An operating system 32 and a control module 34 that control processing and information flow within the CAD system; (b) an input module that assists in smooth input operations using various input devices, such as the keyboard 12; 44 (c) Input interpretation module 40 that interprets input information according to the format of command instructions (d) Display module 38 that manages display information and performs display processing according to commands (e) Consists of sub-modules corresponding to commands (f) A database operation module 50 that efficiently searches and stores a large amount of information necessary for the CAD system stored in the database 54. (g) A macro that includes an automatic design program. Macro module 28 that executes the program 26 (h) External system interface 30 that performs information exchange and interlocking processing with other CAD systems;
In order to maintain expandability and maintainability, the AD system includes a system control file 22 that stores the system configuration and standard values, a command control file 42 that stores the operability of each command and program control procedures, and display device models. and an auxiliary file such as a display control file 36 that stores the configuration. In addition, as other auxiliary items, a graphics processing library 46 that processes graphics;
A display library 48 for displaying on the graphic display device 8, a drawing utility 56 for outputting processing results on the graphic output device 6, a data exchange utility 52 for connecting with other CAD systems, etc. are prepared. .

Next, each module will be briefly explained. The control module 34 modularizes the program group and intervenes between each module to centrally manage control within the system and standardize calling procedures. Its functions include start, end, abnormal handling, execution control of each module, execution history recording, debugging function, and special processing with the operating system 32.

The input module 44 provides the user with a comfortable input procedure in accordance with specifications that organize and unify various input methods of various input devices. Its functions include prompting the user to instruct the user on the type of information to be input, the input method and input device, selecting the input device, and converting the input information into a standard format.

The input interpretation module 40 supports a variety of input instruction methods, improves input operability, and maintains system expandability by unifying the method of interpreting input information and displaying results. Its functions include interpreting input information and displaying the interpretation results.

The display module 38 uniformly processes various display operation requests and manages display information and display states.

The command module 24 centrally manages input argument formats, calling processing programs according to commands, and processing results, thereby maintaining maintainability and expandability of the system.

The database operation module 50 standardizes the request method from other modules and provides recovery means when a failure occurs. Its function is to manage the database usage status, operate the database 54, and perform processing when a failure occurs.

[0015] The external system interface 30 standardizes the exchange of information with other systems and aims to make effective use of the CAD system. Its function is to exchange information with external systems and control the operation of external programs.

The macro module 28 controls the execution of the CAD system according to the created macro program 26. Its function is to translate and execute the macro program 26.

A method for creating a three-dimensional model using the CAD system configured as described above will be explained by giving an example.

In a CAD system, when defining the shape of a three-dimensional model, the method is, for example, from the perspective view of the three-dimensional model shown in FIG. 3 to the plan view (view from one direction of the arrow) and side view shown in FIG. (views from two directions as viewed from the arrow) are obtained, and shape definition work is performed by synthesizing each dimension of these drawings. Note that the data processing in this case is well known and will not be described here.

Here, in order to facilitate understanding of the embodiments of the present invention, processing of geometric surfaces will be explained.

First, the procedure for creating the shape shown in FIG. 5 will be explained. As shown in FIG.
Lines 152, 154, 156 defined with predetermined dimensions from
, 158 are created. Next, cross-sectional lines LN1 and LN2 are generated along the reference line 150, and this is defined as a three-dimensional model A consisting of a group of shaped surfaces. Similarly, lines 162, 164, 166, 168 defined by predetermined dimensions from the reference line 160
Create. Then, set the cross-section lines LN3 and LN4 as reference line 1.
60, and consists of a group of shaped surfaces
shall be.

Next, an intersection line 170 between the three-dimensional model A and the three-dimensional model B is determined. Various methods can be considered to obtain this line of intersection 170, but for example, each three-dimensional model A and B are subdivided, their coordinates are determined, and three-dimensional model A is placed in the divided coordinate portions.
If data for both 3D model B and 3D model B exist, it can be determined that that part is a part where the surfaces intersect.

Once this intersection line has been found, as shown in FIG. 7, unnecessary parts of each three-dimensional model A and B (portions indicated by broken lines in the figure) are deleted.

Finally, by performing a process of combining the three-dimensional models A and B obtained, the shape shown in FIG. 5 is obtained.

[0024] Since the processing of the lines projected onto the three-dimensional models A and B described in the examples described below is equivalent to finding the line of intersection with the plane through which the line passes in the three-dimensional models A and B, the above A method of finding the intersection line between three-dimensional models A and B can be applied.

Examples will be explained below. In this embodiment, when synthesizing shapes from the arrow direction, not only a method using a wire frame (edge line) but also a method of directly cutting out or raising a three-dimensional shape is used. A basic figure manipulation method will be explained using FIGS. 8 to 10.

Two solid bodies 60 and 62 existing in a specific positional relationship shown in FIG.
(Hereinafter, this function will be referred to as function 1). In this case, the cutting lines 64 and 66 can be specified by positioning them below the solid bodies 60 and 62 and projecting them onto the solid bodies 60 and 62.

Next, as shown in FIG.
, 66 are connected by a surface (hatched portion) 68 (hereinafter, this function will be referred to as function 2).

Further, FIG. 10 shows a case where lines 74 and 76 are provided between two solid bodies 70 and 72 that exist in a specific positional relationship, and the solid bodies 70 and 72 are connected using this line. For example, a line 74a and a line 74b are defined between the solid bodies 70 and 72, and the line 74 is determined as a composite line thereof, and
Line 76a and line 76b are defined, and line 76 is determined as their composite line. Then, the lines 74 and 76 and the solid bodies 70 and 72 are connected by surfaces 78, 80, and 82 (hereinafter, this function is referred to as function 3).

An example of creating a specific three-dimensional shape using the above method will be explained with reference to FIGS. 11 to 18.

In FIG. 11, lines 86a, 88a, and 90a are applied to the three-dimensional shape 84 at predetermined positions, respectively. In this case, the function 1 is applied to the line 86a, and the right half of the three-dimensional shape 84 is cut out by the line 86. And line 8
8a and 90a, apply function 2 to obtain a composite line 88 of line 88a and line 90a, create a surface between line 86 and line 88, and intersect the three-dimensional shape 84 between line 88 and line 90. A surface is also formed between the parts. As a result, the three-dimensional shape 84 becomes a three-dimensional shape 96 shown in FIG.

Next, as shown in FIG. 13, lines 92a and 94a are applied to the three-dimensional shape 96 shown in FIG. 12, and the line 92a is projected onto the wall of the three-dimensional shape 96 by applying function 1. By cutting the wall surface of the three-dimensional shape 96 along the line 92 and applying function 3, a composite line 94 of the line 92a and the line 94a is obtained, a surface is created between the line 92 and the line 94, and the line shown in FIG. A surface is created between 90 and line 94 shown in FIG. As a result, a three-dimensional shape 100 shown in FIG. 14 is created.

In FIG. 15, by applying function 1 to each of the surfaces 102 and 104 of the three-dimensional shape 100 shown in FIG.
By cutting along the projected line 100 and applying function 3, line 98a and line 100a are created at the bottom of surface 102.
As shown in FIG.
The cut position and the composite line are connected by a surface. Furthermore, the composite line and line 100 are connected by a surface. In this way, a three-dimensional shape 105 shown in FIG. 16 is created.

Furthermore, in FIG. 17, for the three-dimensional shape 105 shown in FIG. 16, in order to make the step created by the line 98 an inclined surface, the predetermined position of the surface 106 is changed to 108a is cut along the projected line 108, and the cut location along the line 98 shown in FIG. 15 and the line 10
Join 8 with a surface. In this way, the three-dimensional shape 1 in FIG.
Create 09.

[0034]

[Effects of the Invention] As described above, according to the present invention, by projecting a line from the arrow direction of a three-dimensional model and connecting the lines generated at the portions that intersect with the line with a surface, it is possible to easily A three-dimensional model can be constructed, and when changing the design, there is no need to make changes to individual lines, so the number of design steps can be reduced.

[Brief explanation of the drawing]

FIG. 1 is a schematic configuration diagram of a CAD system to which the present invention is applied.

FIG. 2 is a program configuration diagram of the CAD system.

FIG. 3 is a perspective view of a three-dimensional shape to which the method of the present invention is applied.

4 is a plan view and a side view of FIG. 3 viewed from each arrow direction; FIG.

FIG. 5 is a diagram combining two three-dimensional models.

FIG. 6 is an explanatory diagram when two three-dimensional models are combined.

FIG. 7 is an explanatory diagram for deleting unnecessary parts of two three-dimensional models.

FIG. 8 is a diagram showing the basic function of the method of the present invention, and is a diagram of cutting out a plurality of solids with lines.

FIG. 9 is a diagram illustrating the basic function of the method of the present invention, in which the edges of a plurality of solids are connected by a surface.

FIG. 10 is a diagram showing the basic function of the method of the present invention, and is a diagram of connecting a plurality of solids with a plurality of planes.

FIG. 11 is an explanatory diagram of an embodiment of the method of the present invention, in which a three-dimensional shape is corrected using basic functions.

FIG. 12 is a diagram after the three-dimensional shape of FIG. 11 has been corrected.

FIG. 13 is a diagram after the three-dimensional shape of FIG. 12 has been corrected.

FIG. 14 is a diagram after the three-dimensional shape of FIG. 13 has been corrected.

FIG. 15 is an explanatory diagram for providing a step on the plane of FIG. 14;

FIG. 16 is a diagram after the three-dimensional shape of FIG. 15 has been corrected.

FIG. 17 is an explanatory diagram for making the step in FIG. 16 oblique.

FIG. 18 is a diagram after the three-dimensional shape of FIG. 17 has been corrected.

[Explanation of symbols]

2...Computer 4...Mass storage device 6...Graphic output device 8...Graphic display device 10...Tablet 12...Keyboard 14...Mouse 16...Light pen

Claims (3)

[Claims] Claim 1: A method for creating a three-dimensional model using a CAD system, in which an outline shape is defined by inputting shape numerical values of a reference three-dimensional model, and at least two lines projected from an arrow direction to the three-dimensional model are defined. A method for creating a three-dimensional model, characterized in that a three-dimensional model having a desired shape is created by connecting surfaces between the two. 2. The method according to claim 1, wherein the line is a line generated at a position where the projected line intersects the original three-dimensional model. 3. The method according to claim 1, wherein the line is a line generated at a position where two lines projected from two arrow directions onto the three-dimensional model intersect. .