JP2004110285A - Apparatus, method and program for checking data on curved surface and recording medium - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a curved surface data checking apparatus which detects a clearance such that where curved surfaces should adjoin each other, their boundary lines are spaced apart by an amount slightly greater than the tolerance of a system. <P>SOLUTION: The curved surface data checking apparatus includes a clearance candidate loop group detecting part 12 for detecting a group of loops composed of a group of boundary lines of adjacent curved surfaces, the loops serving as candidates for the clearance between the adjacent curved surfaces; a clearance determining part 13 for determining whether or not each loop of the group of loops serving as the candidates for the clearance is the clearance; and a result output part 14 which outputs information (position and size of the clearance) on the clearance detected by the clearance determining part. The clearance between the three-dimensional adjacent curved surfaces composed of curved surface data is detected and precisely and effectively reported to a system operator. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a curved surface data check device, a curved surface data check method, a program, and a recording medium, and is suitable for use in a three-dimensional CAD / CAM / CAE / CG that handles a three-dimensional shape.
[0002]
[Prior art]
An important point in the modeling of a three-dimensional part using CAD technology is that the boundary lines between adjacent curved surfaces of the curved surface group constituting the modeled component are guaranteed to be within the tolerance of the system. It is to be done.
However, if the design intention is that the boundary lines between the curved surfaces that are supposed to be adjacent do not match each other and the part data is completed with a gap remaining, it will cause a serious problem in the downstream process using that data Will be. In the case of analysis by CAE, it is not possible to obtain a correct result, and in the case of processing, uncut portions are left.
This problem is often taken up as one of the important factors that can influence the quality in discussions and efforts on PDQ (Product Data Quality) in the industry.
[0003]
In the case of a system such as Solid Modeler, which adopts a data structure that expresses the boundary line that should be matched between adjacent surfaces as a boundary line shared by adjacent surfaces, if the designer intentionally models as an adjacent surface, There is no gap between the curved surfaces.
In addition, the system guarantees that there is no gap between curved surfaces modeled as adjacent surfaces.
[0004]
[Problems to be solved by the invention]
However, if the separately modeled surfaces are simply placed adjacent to each other, or if the data of the surface group is imported from another system in a format that cannot express the shared boundary between adjacent surfaces, Not guaranteed.
In such a case, it is necessary for the system to recognize the boundary lines at places where the curved surfaces should be adjacent to each other as a shared boundary line.
However, in order to be regarded as a shared boundary line, in other words, in order for the system to recognize that the curved surfaces are adjacent to each other, the distance between the boundary lines must be within an allowable error defined by the system.
[0005]
For example, when data of a curved surface group is fetched from another system, due to differences in the tolerance of the system, the fetching system satisfies the accuracy as an adjacent surface, but the fetching system does not. Conditions may not be met. In such a case, the boundary may be made to coincide with each other by fixing one curved surface and slightly deforming the shape of the other curved surface, and then the system may recognize the boundary as a shared boundary.
[0006]
By the way, in a series of operations for causing the system to recognize a boundary between curved surfaces to be adjacent as a shared boundary, the distance between the boundaries is not within the tolerance of the system, and the shared boundary, which is a location adjacent to the system. It is necessary to specify a portion that remains as a gap without being recognized as a gap.
If a color is applied not only to the boundary portion but also to the inner side of each curved surface, the portion remaining as a gap remains without being colored, so that it can be visually grasped.
For example, a so-called shading display function normally provided in a CAD system may be used.
[0007]
However, the gap is often very long if it should be an adjacent surface. In such a location, the curved surfaces on both sides of the gap are displayed in a shading manner, so that the gap is crushed and displayed, making it difficult to confirm that the gap is present. Further, a gap left between curved surfaces facing the opposite side to the viewpoint may be missed.
Further, it is necessary to know not only the location of the gap but also the size of the gap. If the boundary lines between adjacent curved surfaces are separated by more than the tolerance of the system, it is necessary to slightly deform the curved surface shape so that the boundary lines coincide with each other as described above. is necessary.
[0008]
The present invention has been made in view of the above-described circumstances, and employs a data structure such as a solid modeler that expresses a boundary line that should be matched between adjacent surfaces as a boundary line shared by adjacent surfaces. In a system, a curved surface data check device, a curved surface data check method, a program, and a recording medium for detecting a gap where curved surfaces should be adjacent to each other and a boundary line is slightly separated from the system by an allowable error are provided. The purpose is to:
[0009]
[Means for Solving the Problems]
In order to solve the above problem, a curved surface data checking device according to claim 1 of the present invention is a curved surface data checking device for detecting a gap between adjacent curved surfaces in a three-dimensional shape constituted by curved surface data. A gap candidate loop group detection unit that obtains a loop group composed of boundary lines of adjacent curved surfaces that are candidates for a gap, and a gap determination unit that determines whether each loop of the loop group of the gap candidates is a gap. And a result output unit for outputting information on the gap detected by the gap determination unit.
[0010]
According to a second aspect of the present invention, in the curved surface data checking device according to the first aspect, the result output unit outputs information capable of specifying the position of the gap.
According to a third aspect of the present invention, in the curved surface data checking device according to the first aspect, the result output unit outputs information capable of specifying the size of the gap.
[0011]
In the curved surface data checking method according to a fourth aspect of the present invention, in the curved surface data checking method for detecting a gap between adjacent curved surfaces in a three-dimensional shape composed of curved surface data, a method for determining a gap between adjacent curved surfaces is provided. A step of obtaining a loop group composed of a group of boundary lines of a curved surface; a step of determining whether or not each loop of the loop group of the gap candidates is a gap; and a step of outputting information on the detected gap. It is characterized by the following.
[0012]
According to a fifth aspect of the present invention, in the curved surface data checking method according to the fourth aspect, the information on the detected gap is information capable of specifying the position of the gap.
According to a sixth aspect of the present invention, in the curved surface data checking method according to the fourth aspect, the information on the detected gap is information capable of specifying the size of the gap. .
[0013]
A program according to claim 7 of the present invention is a program for checking three-dimensionally shaped surface data using a computer, wherein the computer checks the surface data according to claim 1, 2 or 3. This is a program for executing the functions of the device.
A recording medium according to claim 8 of the present invention is a computer-readable recording medium on which the program according to claim 7 is recorded.
[0014]
With the above configuration, in a system such as a solid modeler, which adopts a data structure that expresses a boundary line that should be matched between adjacent surfaces as a boundary line shared by adjacent surfaces, a portion where curved surfaces should originally be adjacent to each other In addition, it is possible to accurately and effectively notify the system operator of the location and the size of the boundary line that is slightly separated from the tolerance of the system and remains as a gap.
[0015]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, an embodiment of a curved surface data check device of the present invention will be described with reference to the drawings. In the following description of the embodiment, it is assumed that the surface data check device of the present invention is incorporated in a CAD system.
[0016]
FIG. 1 is a block diagram showing a hardware configuration for realizing a general CAD system.
In FIG. 1, a CAD system includes a CPU (Central Processing Unit) 101 that performs calculations and processes on data and the like, a memory 102 that stores programs and data and the like, a keyboard that inputs programs and data based on key operations, and a general keyboard. An input device 103 which is a pointing device such as a mouse for moving a mark called a mouse cursor and inputting data based on the movement, a display device 104 such as a graphic display for displaying graphics on a screen, a program or CAD The apparatus includes at least an external storage device 105 such as a hard disk for storing data and a bus line 106 for interconnecting them.
The CAD system generates a figure or the like by performing an operation or processing according to a predetermined program based on the contents of an instruction given by operating the input device 103 such as a keyboard or a mouse, and displays the figure or the like on the screen of the display device 104. Display above.
[0017]
FIG. 2 is a block diagram showing a functional configuration of the surface data check device of the present invention incorporated in a CAD system. In FIG. 2, the curved surface data check device 10 includes the functions of an input unit 11, a gap candidate loop group detection unit 12, a gap determination unit 13, and a result output unit 14.
[0018]
Next, the configuration and operation of the curved surface data check device 10 will be described with reference to FIGS. FIG. 3 is a flowchart showing the procedure of the entire process of the curved surface data checking device 10 of the present invention.
First, data of a three-dimensional shape specified by the operator of the system using the input device 103 is read from the external storage device 105 and input, and a gap candidate loop detection process is performed (step S1). In step S1, the input unit 11 and the gap candidate loop group detection unit 12 are configured.
A gap determination process is performed from the detected gap candidate loop group to determine a gap loop and the size of the gap (step S2). Step 2 constitutes the gap determination unit 13.
The detected gap information is output to the display device 104 such as a display (step S3). The result output unit 14 is configured in step S3.
[0019]
Next, an outline of the gap candidate loop group detection processing will be described. FIG. 4 is an example in which a case where the non-shared boundary line has a gap in the three-dimensional shape is displayed. FIG. 5 shows a part of the shape of FIG. 4, which is a curved surface S ₁ represented by four ridges (B ₁₁ , B ₁₂ , B ₁₃ , B ₁₄ ) and four ridges (B ₂₁ , B ₂₁ , B ₂₁ , B ₁₄ ). B _{22, B 23, B} has a curved surface _{S 2} represented by _24), and the curved surface _{S 1} and _{S 2} and that share vertices _{P 1} and _{P 2} are. In other words, a state where a gap does not coincide with the ridge line B ₁₁ and ridge B _21.
[0020]
In such a case, the gap candidate loop group detection processing first detects a boundary line (here, eight ridge lines) from the three-dimensional shape data and registers it in the table T1 (the state shown in FIG. 5B). .
Next, the registered boundary lines are taken out one by one from the table T1, and if this boundary line is not a shared boundary line, it is registered in the table T2. In Figure 5, B ₁₁ are registered as a component of the first loop of the table T2.
[0021]
Next, a boundary line adjacent to the boundary line (B ₁₁ ), which is a non-shared boundary line, is searched from the table T1, and registered as a loop in the table T2. In Figure 5, non-covalently border adjacent to the boundary line _{B 11} is _{B 21,} as a component of the first loop of the table _T2, Add _{B 21.} Whether or not they are adjacent can be determined based on whether or not they have a boundary line and a shared vertex registered in the table T2 as components of the loop.
[0022]
The operation is continued until there is no border line adjacent to the border line (B ₁₁ ) or the loop registered in the table T2 is closed.
When this operation is completed for one boundary, another unprocessed boundary line is extracted from the table T1, and the above operation is repeated.
[0023]
FIG. 6 is a flowchart illustrating a processing procedure of the gap candidate loop group detection unit 12 that detects the loop of the gap candidate described above.
First, a table T1 is created in which the boundary lines of the curved surface groups existing in the input three-dimensional shape data are used as elements, and the table T2 for storing the gap candidate loop is left empty (step S11).
[0024]
An undetermined boundary line B1 is extracted from the boundary line group table T1 (step S12). If there is no undetermined boundary line in the table T1 (NO in step S13), the processing of all the boundary lines has been completed, and the detection processing of the gap candidate loop group ends.
[0025]
On the other hand, when there is an undetermined boundary line in the table T1 (YES in step S13), and when the extracted boundary line B1 is a shared boundary line (YES in step S14), the boundary line B1 is not a candidate for a gap. Is determined, and the process returns to step S12 to process the next boundary line.
If the extracted boundary line B1 is not a shared boundary line (NO in step S14), this boundary line B1 is newly registered in the table T2 as a component of the loop L (step S15). Here, only the boundary line B1 is registered in the loop L.
[0026]
An undetermined boundary line B2 is extracted from the boundary line group table T1 (step S16). If the extracted boundary line B2 is not adjacent to the loop L (NO in step S17), the process returns to step S16 to search for another undetermined boundary line.
If the extracted boundary line B2 is adjacent to the loop L (YES in step S17), the boundary line B2 is additionally registered in the table T2 as a component of the loop L, and the boundary line B2 is determined to have been determined (step S18). .
When the loop L is not closed and there is a boundary line that has not yet been determined as an adjacent boundary line (NO in step S19), the process returns to step S16.
If the loop L is closed or if all the boundaries have already been determined as adjacent boundaries (YES in step S19), the process returns to step S12 to perform the next loop.
[0027]
FIG. 7 is a flowchart illustrating a processing procedure of the gap determination unit 13.
First, an undetermined loop L is extracted from the table T2 of the gap candidate loop group (step S21).
If there is no undetermined loop (NO in step S22), all gap candidate loops have been processed, and the gap determination processing ends.
[0028]
It is determined whether or not the taken out loop L is a gap (step S23).
If this loop L is not a gap (NO in step S24), this loop has been determined and the process returns to step S21.
On the other hand, when the loop L is a gap (YES in step S24), the fact that the loop is a gap is recorded in the table T2 (step S25).
Further, the size of the gap of the loop L is obtained and registered in the table T2 in association with the loop L (step S26).
[0029]
FIG. 8 is a flowchart illustrating a processing procedure of the gap information result output unit 14.
First, a loop having a gap that has not been output is extracted from the table T2 (step S31).
If there is no loop having a gap that has not been output (NO in step S32), the result output ends.
On the other hand, if there is a loop having a gap that has not been output (YES in step S32), gap information (eg, the position of the gap and the size of the gap) associated with the loop is extracted and sent to the display device 104 such as a display. Output, and the process returns to step S31 assuming that this loop has been output.
As shown in FIG. 9, this output is colored so that the corresponding portion of the three-dimensional gap displayed on the display device 104 can be distinguished from the others, is displayed with an identification ID added, and is displayed. Outputs the size of the gap in character format.
[0030]
Furthermore, the present invention is not limited to only the above-described embodiments. Each function of the curved surface data checking device according to the above-described embodiment is programmed and written in advance on a recording medium such as a CD-ROM, and the CD-ROM is mounted with a medium driving device such as a CD-ROM drive. It goes without saying that the objects of the present invention can be achieved by installing these programs in a computer, storing these programs in a memory or a storage device of the computer, and executing the programs.
In this case, the program itself read from the recording medium implements the functions of the above-described embodiment, and the program and the recording medium on which the program is recorded also constitute the present invention.
[0031]
As a recording medium, a semiconductor medium (for example, ROM, nonvolatile memory card, etc.), an optical medium (for example, DVD, MO, MD, CD-R, etc.), a magnetic medium (for example, magnetic tape, flexible disk, etc.), etc. Any of these may be used.
[0032]
Further, not only the functions of the above-described embodiments are realized by executing the loaded program, but also the operating system or the like performs part or all of the actual processing based on the instructions of the program, and the processing performs the processing described above. The case where the functions of the embodiments described above are realized is also included.
[0033]
When the above-described program is stored in a storage device such as a magnetic disk of a server computer and distributed in a form such as download from a user computer connected via a communication network such as the Internet, the storage device of the server computer Are also included in the recording medium of the present invention.
[0034]
【The invention's effect】
As described above, according to the present invention, in a system such as a solid modeler, which adopts a data structure in which a boundary line that should be matched between adjacent surfaces is expressed as a boundary line shared by adjacent surfaces, a curved surface is originally used. Can be accurately and effectively notified to the operator of the system of the location and the size of the location that should be adjacent, where the boundary line is slightly separated from the tolerance of the system and remains as a gap.
[Brief description of the drawings]
FIG. 1 is a block diagram showing a hardware configuration for realizing a general CAD system.
FIG. 2 is a block diagram showing a functional configuration of a curved surface data check device of the present invention incorporated in a CAD system.
FIG. 3 is a flowchart relating to the entire process of the curved surface data checking device of the present invention.
FIG. 4 is a display example of a three-dimensional shape having a gap.
FIG. 5 is a diagram for explaining gap candidate loop group processing;
FIG. 6 is a flowchart illustrating a processing procedure of a gap candidate loop group detection unit.
FIG. 7 is a flowchart illustrating a processing procedure of a gap determination unit.
FIG. 8 is a flowchart illustrating a processing procedure of a result output unit.
FIG. 9 is an output example of gap information.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 10 ... Curved surface data check device, 11 ... Input part, 12 ... Gap candidate loop group detection part, 13 ... Gap determination part, 14 ... Result output part, 101 ... CPU, 102 ... Memory, 103 ... Input device, 104 ... Display device , 105: external storage device, 106: bus line.

Claims (8)

In a curved surface data check device for detecting a gap between adjacent curved surfaces in a three-dimensional shape constituted by curved surface data, a gap candidate for obtaining a loop group constituted by a boundary line group of adjacent curved surfaces, which is a candidate for a gap between adjacent curved surfaces. A loop group detection unit, a gap determination unit that determines whether or not each loop of the loop group of the gap candidate is a gap, and a result output unit that outputs information about the gap detected by the gap determination unit A curved surface data check device characterized by the following. 2. The surface data check device according to claim 1, wherein the result output unit outputs information capable of specifying a position of the gap. 2. The surface data checking device according to claim 1, wherein the result output unit outputs information capable of specifying the size of the gap. Obtaining a loop group formed by a boundary line group of adjacent curved surfaces, which is a candidate for a gap between adjacent curved surfaces, in a curved surface data checking method for detecting a gap between adjacent curved surfaces in a three-dimensional shape constituted by curved surface data; A step of determining whether or not each loop in the loop group of gap candidates is a gap and a step of outputting information on the detected gap. 5. The surface data check method according to claim 4, wherein the information on the detected gap is information capable of specifying a position of the gap. 5. The surface data check method according to claim 4, wherein the information on the detected gap is information capable of specifying the size of the gap. A program for checking three-dimensionally shaped surface data using a computer, the program causing the computer to execute the function of the surface data check device according to claim 1. A computer-readable recording medium on which the program according to claim 7 is recorded.

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