JPH06236421A - Curved surface model generating method - Google Patents

Abstract

PURPOSE:To provide a curved surface model generating method capable of performing high speed processing. CONSTITUTION:This method is equipped with first step 13 where the input of each sequence of points data representing point coordinates on plural curves measured on the surface of a material to be measured is accepted, and curve geometric data and curve managing data are generated by analyzing each sequence of points datum, second step 14 where a wire frame is generated by dividing the material to be measured into plural slave curved surfaces and the update of the curve managing data and the generation of curved surface managing data are performed by defining relation between each curve comprising the wire frame and slave curved surface, third step 15 where a processing schedule optimum for the generation of curved surface geometric data is generated based on the relation between the curve and the slave curved surface defined at the step 2, and fourth step 16 where the curved surface geometric data of the slave curved surface based on the data of each curve comprising the wire frame fitting in the processing schedule is generated, and the connection relation of the managing data and geometric data of the curve and the slave curved surface is managed by at least one common field.

Description

Detailed Description of the Invention

[0001]

The present invention relates to a CAD (Computer Aid)
ed Design: Computer-aided design / CAM (Comput
er Aided Manufacturing (Computer Aided Manufacturing) system, especially for products designed with complicated curved surfaces, the point sequence on the product model of the three-dimensional shape is measured, and the computer-controlled NC (Numerical Contro
l: Numerical control) A curved surface model creating method for creating a curved surface model corresponding to each curved surface constituting a product model for use in a device or the like.

[0002]

2. Description of the Related Art A conventional curved surface model is created according to the procedure shown in the flowchart of FIG.

First, a plurality of lines are set on the curved surface of a product model created by a product shape designer, and the three-dimensional coordinates of a plurality of measurement points on these lines are measured as point sequence data (step 101). ). The measured point sequence data is
Each line on the curved surface is identified and input to the CAD device (step 102).

Next, an approximate curve is created for each line on the curved surface using the point sequence data input to the CAD device (step 103). A boundary wireframe model in which a part of the curved surface of the product model is represented is created using these plural approximate curves (step 104).

Three-dimensional surface data is created in the area surrounded by the boundary lines of the created boundary wire frame model by using the boundary line data of each surface candidate (step 105).

However, when creating surface data, it is necessary to connect adjacent surfaces smoothly, so it is necessary to refer to other surface data. Therefore, after all the surface data have been created, the product shape designer confirms on the screen whether the three-dimensional curved surface composed of these surface data is smooth (step 106).

If there is a non-smooth portion, it is necessary to modify the approximate curve of the boundary used to create the surface of this portion, or change the boundary line of the surface candidate. Then, in order to modify the approximate curve, the coordinate value of the point sequence of the measurement data which is the basis of the approximate curve must be modified. Also, in order to change the boundary line of the surface candidate, the boundary warrior frame must be changed.

In such a correction process, it is very difficult to determine which point coordinates should be corrected or which surface candidate boundary line should be changed. The correction process cannot completely correct. Then, the correction process is repeated several times to finally complete a smooth curved surface model (step 107).

The curved surface model completed through the above process is used as the control data for the production of the product mold and the product processing apparatus.

A technique for measuring the three-dimensional shape of a product model and inputting it into a CAD device is disclosed in JP-A-1-144174.
Is disclosed in.

A technique for creating a boundary wire frame model from a plurality of approximate curves is disclosed in Japanese Patent Laid-Open No. 63-
No. 118880.

[0012]

However, in the conventional method of creating a curved surface model, the point sequence data measured in step 101 often contains a measurement error due to the constraint of the measuring device. If an approximate curve is created based on the point sequence data containing this error, the approximate curve may not be smooth, or the approximate curves that are boundaries of the same surface may not intersect. If the approximated curves do not intersect, the operator must deform the curves on the computer display to force the approximated curves to intersect.

The curved surface data completed through such deformation processing often has a shape different from that of the product model. And the partial correction of the curved surface data in this case is
It is necessary to return to the setting process of the approximate curve in step 103. For this reason, the creation of all curved surface data, which requires the most computation time, must be performed by the computer again from the beginning, and the correction process took a very long time.

Further, the boundary line often becomes completely different from the measured data during the repeated correction processing. Therefore, it was almost impossible to make the curved surface model created by the geometrical method using the boundary wireframe model into the shape of the product model.

The present invention solves such a problem and provides a method capable of obtaining optimum 3D surface data by rapidly creating an appropriate boundary wireframe model from measured 3D shape data. The purpose is to do.

[0016]

In order to solve the above-mentioned problems, a curved surface model creating method of the present invention uses a series of point data indicating point coordinates on a plurality of curves measured from the surface of a measured object. The first step of inputting and analyzing each point sequence data to create curve geometric data and curve management data, and dividing the DUT with a plurality of child curved surfaces to create a wire frame, Based on the second step of updating the curve management data and creating the child surface management data by defining the relationship between each curved line and the child surface, and the relationship between the curve and the child surface defined in the second step, Based on the third step of creating the optimum processing schedule for creating the curved surface geometric data, and the data of each curve forming the wire frame in accordance with the processing schedule created in the third step. And a fourth step of creating a curved surface geometric data of itako curved, management data and geometric data of curves and child curved surface, the relationship ties at least one common field is managed.

Here, the areas of the management data and geometric data of the curves and child curved surfaces created or updated in the processing of each step may be dynamically created. Also,
The management data of the curved surface and the child curved surface may manage the mutual priority of the curved surfaces or the mutual relations of the child curved surfaces or the connection relationship, or may manage the relationship with the curve surrounding the child curved surface.

Further, there may be a step of modifying the curved surface geometric data created in the fourth step.

[0019]

According to the curved surface model creating method of the present invention, the curve geometric data and curve management data created in the first step, the child curved surface management data created in the second step, and the fourth step are created. Regarding the curved surface geometric data, the connection relation is managed by at least one common field.

In each step, by utilizing the data of this connection relationship, it is possible to process at high speed with the minimum required data access. Therefore, the processing time of each step is significantly reduced.

[0021]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the accompanying drawings.

First, the configuration of the CAD device 20 to which the curved surface model creating method according to this embodiment is applied will be described with reference to the block diagram of FIG. The CAD device 20 includes a host computer 30, a plurality of CAD terminals 40 to 46,
Three-dimensional shape measuring device 50 for measuring the surface shape of a product model
And a processing device 60 for processing the material into the same shape as the product model
It has and. The host computer 30 includes a central processing unit 31, a main storage device 32, and a hard disk device 3.
3, 34, an interface device 35 for converting the data measured by the three-dimensional shape measuring device 50 into a data format that can be processed by the host computer 30, and a central processing device 31.
And a conversion device 36 for giving a control signal from the processing device 60 to the processing device 60.

The hard disk device 33 stores a data management D / B (database) 33a. The data management D / B 33a stores each point sequence data, each curve data, each surface data, and this data. Type information, priority information, connection relation information, etc. are registered. Further, the hard disk device 34 stores a diagram D / B (database) 34a, and this diagram D / B33 is stored.
In a, curve data whose data format is converted by the interface device 35 and attribute information (feature line, X
The Z (0) cross section, the YZ (5) cross section, etc.) are registered.
Furthermore, the three-dimensional shape measuring apparatus 50 employs a method of measuring the surface shape by, for example, irradiating the surface of the product model with light and measuring the time until the reflected light is received.

The CAD device 20 is used to create a curved surface model according to the creating method of the present embodiment described below.

Next, the outline of the curved surface model creating method according to this embodiment will be described with reference to the flowchart of FIG. First,
On the curved surface of the product model created by the product shape designer, a plurality of lines representing the characteristics of this curved surface are selected. Then, a plurality of measurement points are set on each selected line, and the three-dimensional coordinates of these measurement points are measured by the three-dimensional shape measuring apparatus 50 as point sequence data (step 11). The measured point sequence data is identified for each line on the curved surface, and CA
The data is input from the D terminal 40 to the CAD device 20 (step 12). The input point sequence data and the attribute information of this point sequence data are registered in the line diagram D / B 34a.

Next, the point sequence data input to the CAD device 20 is read from the diagram D / B 34a, and an approximate curve is created for each line on the curved surface (step 13). The data of these plural approximate curves and the data (priority information etc.) related to these approximate curves are data management D / B.
33a is registered.

The data of a plurality of approximate curves and the data related to these approximate curves are read from the data management D / B 33a to create a boundary wire frame model (step 14). What is the boundary wireframe model?
It is a model showing the sizes and shapes of a plurality of surface elements that make up a product model.

Next, an optimization process for creating an optimum process schedule for creating a curved surface is performed from the created boundary wire frame model (step 15). On this occasion,
Curve priorities and face-to-face connections are considered. Then, using the boundary line data of each surface candidate in the part surrounded by the boundary line of the boundary wire frame model, 3
A dimensional curved surface model is created (step 16). This curved surface model is created according to the procedure of the processing schedule created in step 15 using a geometric method as shown in "Shape processing engineering by computer display (I)" published by Nikkan Kogyo Shimbun. Be seen. Also,
Since the relationship between adjacent surfaces has already been considered in the stage of optimization processing, in step 16, the surfaces may be created according to the schedule.

In this way, the three-dimensional curved surface model created by approximating all the curved surfaces on the product model is displayed on the screen,
The product shape designer confirms the difference from the actual product model while visually observing this screen (step 17).

When there is a large difference that causes a problem, the product shape designer inputs the correction of the approximate curve or the change of the boundary line of the surface candidate from the CAD terminal 40, and thereby the three-dimensional shape is obtained. The curved surface model is modified (step 18).

In the correction of the approximate curve, the intersection is adjusted and the curve is smoothed so as to match this approximate curve with another approximate curve. Therefore, compared to the conventional example in which all the approximate curves are readjusted, it takes a shorter time. Can be fixed. Further, since the change of the boundary line of the surface candidate is readjusted only for the curved surface including the boundary line affected by this change, it can be corrected in a shorter time than the conventional example in which all the curved surfaces are readjusted.

For the curve or boundary wireframe model that has been corrected, the optimization process is performed again, but the data relating to the curve / curved surface is managed by the data management D / B3.
Since it is managed relationally (relational type) on 3a, only the curve / curved surface affected by the modified boundary line of the curved line or surface candidate can be extracted, and reprocessing scheduling can be easily performed (step 15). Therefore, the optimization process can be performed in a shorter time than the conventional example in which all the curves and curved surfaces are reprocessed.

By performing such processing, curved surface data suitable for the product model can be created in a short time.

Next, with respect to each table of the data management D / B 33a for managing the three-dimensional graphic data, which is the feature of this embodiment, as relational (relational) data, FIG.
This will be described with reference to FIG.

FIG. 3A shows the structure of the process control information table. This table stores creation information including a creator of the data and a creation date, and processing level information including a data level and a name of an already processed process.

FIG. 3B is a diagram showing the structure of the curve optimum processing order data table. This table is created at the stage where the optimization processing of step 15 is completed, and the data of the number of curves to be processed, the processing priority condition due to the attribute difference of the lines for which the optimization processing is executed, and the curve with high priority The curve number and information on whether the calculation is completed are stored in order.

FIG. 3C is a diagram showing the structure of the optimum processing order data table for curved surfaces. This table is also shown in Figure 3.
Similar to the optimum processing order data table of the curve in (b),
Created when the optimization process of step 15 is completed,
Data of the number of curved surfaces to be processed, curved surface numbers and calculation control information are stored in descending order of priority.

FIG. 3D is a diagram showing the structure of the curve index data table showing the basic form of the curve. This table stores attributes indicating what kind of cross-section and characteristics the curve shows, usage pattern data indicating the boundary line or the internal line of the curved surface, and update information of the curve.

FIG. 4E is a diagram showing the structure of a curve feature data table in which detailed information other than geometric information is shown for each curve. This table stores surface information using a curve, connection information with another curve, and an address of a curve coefficient table corresponding to the curve.

FIG. 4 (f) is a diagram showing the structure of the curved surface index data table showing the basic form of the curved surface. The table stores the curved surface number and the curved surface update information.

FIG. 4G is a diagram showing the structure of the curved surface feature data table in which details other than geometrical information are shown for each curved surface. In this table, information on the boundary line for forming the curved surface, information on the internal reference line, connection information with another curved surface, and the address of the curved surface coefficient table corresponding to the curved surface are stored.

FIG. 5 (h) is a diagram showing the structure of the curve coefficient table for storing the geometrical coefficient of the curve. In this table, curve coefficient data for each level (processing stage) is stored for each curve. Further, the addresses of the curve feature data indicating the features of these curves are stored.

FIG. 5 (i) is a diagram showing the structure of the curved surface coefficient table for storing the geometrical coefficients of the curved surface. In this table, curved surface generation unprocessed information, information on the number of sides forming a curved surface, and created curved surface coefficients are stored.
Further, the addresses of the curved surface feature data showing the features of these curves are stored.

Next, a concrete example of this embodiment will be described with reference to FIGS.
This will be described with reference to FIG. FIG. 6 and FIG. 7 are a flow chart showing a detailed process flow of the present embodiment, and a conceptual diagram showing a flow of data to the data management D / B 33a in each process. Further, FIG. 8 is a diagram showing a simple example of a curved surface model created by this embodiment. Further, FIGS. 9 to 25 show the data management D / s shown in FIGS.
It is a figure which shows the movement of the data in each table of B33a.

First of all, the curved surface creation system user is C
The curved surface creation system is activated from the AD terminal 40 (step 71). Then, the point sequence data of the product model is measured using the three-dimensional shape measuring apparatus 50 (step 72).
In this measurement, the front surface of the product model is placed so as to face the X axis, and the cross-sectional shape parallel to the XZ, YZ, and XY planes and having a constant interval is measured. In addition, a tape is attached to the characteristic curve portion of this product model, and the point sequence data on the tape line is measured.

In order to simplify the explanation, a cross section parallel to the XZ plane and having a Y-axis value of zero is referred to as "XZ (0) cross section",
A cross section having a Y-axis value of 5 is referred to as an "XZ (5) cross section", and a cross section parallel to the YZ plane and having an X-axis value of zero is called "YZ
A (0) cross section ”, a cross section parallel to the XY plane and having a Z-axis value of zero will be referred to as an“ XY (0) cross section ”and the like. In addition, a line to which a tape is attached by a product shape designer as a characteristic curve of a product model will be referred to as a "characteristic line" for description.

A plurality of point sequence data measured in this way and the attribute information of these point sequence data (“feature line”, “X
"Z (0) cross section", "XZ (5) cross section", etc.) are registered for each line in the diagram D / B 34a (step 7).
3). Of the attribute information, the information of the "characteristic line" can be taken in by the product shape designer by inputting this information at the time of measuring this line (or after the measurement). Other information is automatically fetched from the three-dimensional shape measuring apparatus 50.

In the example shown in FIG. 9, the curves (1, 2, 3) are XZ sections, the curve (4) is a characteristic line, and the curve (5) is YZ.
The cross section and the curve (6) assume the YZ (0) cross section, respectively.

These data registered in the diagram D / B 34a are displayed on the CAD device 30 not as a plurality of three-dimensional points but as a curve approximated from these point sequences (step 74). Here, the curved surface creation system initializes each table of the data management D / B 33a, which is a feature of the present invention (step 75).

The tables initialized are the process control information table (FIG. 10A), the curve index data table (FIG. 13D), and the curve feature data table (FIG. 14).
(E) to FIG. 19 (j), a curved surface index data table (FIG. 20 (k) to FIG. 23 (n)), and a curve coefficient table (FIG. 24 (o)). The data input at this stage is described in the “after initialization” column of each table.

In the process management information table (FIG. 10A), the creator name and the creation date are entered as the creation information, and the information that the processing level information is unprocessed data is input. In the curve index data table (FIG. 13D), what kind of curve the total number of curves is “6” for each curve number, for example, the curve (4) is a “feature line”.
Information such as "is entered. Further, in the curve feature data table (FIGS. 14E to 19J),
Temporarily record the number of faces on which the curve will be used, and use this curve (1)
The address at which the curve coefficient table (Fig. 24 (o)) exists is also recorded. Further, in the curved surface index data table (FIGS. 20 (k) to 23 (n)), only the area is secured and no data is input. The curve coefficient table (FIG. 24 (o)) stores the curve coefficient for each curve, and at this stage, the data captured in the diagram D / B 34a is input.

Next, the user of the curved surface creating system inputs the condition change when it is necessary to change the condition of the curve. For example, when the curve measured as the “YZ (0) cross section” at the time of measurement is actually the line that most represents the feature of this product, the attribute information is changed to the “feature line”. In this case, the item of the attribute information “YZ (0)” input for each curve in the curve index data table (FIG. 13D) is changed to “feature line” (step 76).

The next step is to create a boundary wire frame model. To create the boundary wireframe model, the curved surface creation system user selects a plurality of curves to be used as the boundary wireframe model from the displayed approximate curves (step 77). In the case of the example shown in FIG. 9, the curved surface S3 is an area surrounded by the curve (1), the curve (5), the curve (6) and the curve (3), and the curve (2) is used as an internal reference line. Designate (step 78).

Then, the data of the designated approximate curves and the data related to these approximate curves are stored in the curve index data table (FIG. 13 (d)) and the curve characteristic data table (FIG. 14 (e) to FIG. 19 (j)). A boundary wireframe model is created by reading from the above.

As a result of the processing of steps 77 and 78, the curve (1) is used as a boundary line in the item of "Usage form on surface" of the curve index data table (FIG. 13D). In (2), information about the contents such as being used for the boundary line and the in-plane line is input. Further, information on the curved surface number of the set surface is input to the curved surface index data table (FIGS. 20 (k) to 23 (n)). Further, the curve feature data table (FIG. 14 (e) to FIG. 19 (j)) is input with information as to which surface the boundary line or the internal line is used for.

A curved surface characteristic data table (FIG. 21 (l)) and a curved surface coefficient table (FIG. 24 (o)) are newly created.

Curved surface feature data table (FIG. 21 (l))
For each curved surface, the number of the curve of the boundary line that forms the curved surface, the start and end points of the curve at that stage, the internal line information, and the like are input. Curved surface coefficient table (Fig. 24)
(O)) is for storing the surface coefficient for each curved surface, and at this stage, only the line information fetched from the line diagram D / B 34a is still stored. Then, the surface number, information indicating that the surface has not been generated, and the number of boundary lines forming the surface are input.

Next, the priority of the curve is determined (step 79). This is a process for changing the priority of the curve. For example, in this model, "YZ" rather than "feature line" is used.
Since the “(0) cross section” is the more important line, the order is reversed or the like is specified.

Next, scheduling for the optimization process is carried out (step 80). In this step, the curve to be processed with the highest priority is the curve (4) and the next curve (6).
1 (b)) is created. Further, a curved surface optimization processing order table (FIG. 12C) is created in which the curved surface to be processed with the highest priority is the curved surface (3) and the curved surface (2) is next. Further, information indicating that the calculation processing is not performed is recorded in these as the processing status.

Further, in this step, the connection information with other curves is input to the curve characteristic data table (FIGS. 14 (e) to 19 (j)). For example, regarding the curve (1), information indicating that the curve (4) and the curve (6) are connected in a state in which the other side has a high priority, but the curve (5) has its own priority. Information that the connection is made in a high degree is input.

Furthermore, in this step, the surface information to be referred to is input to the curved surface characteristic data table (FIGS. 21 (l) to 23 (n)). For example, the information that the curved surface S1 is connected to two curved surfaces S2 and S3, the information that the curved surface S2 is completely shared with one side, and the curved surface S3 includes one side. Information such as connection is input.

With the priority determined in the optimization process, a process for matching the intersection points of the curves is next performed (step 8).
1). Since the curve is originally on the surface of the product model, it must have an intersection. However, the product model has very small deviations due to measurement errors, and in most cases they do not intersect. If there is no intersection, the curved surface cannot be defined exactly, so the optimum processing order data table (see FIG.
An intersection is adjusted so that a curve having a higher priority, which is already defined in (b), is matched with a curve having a lower priority.

The logic of this intersection adjustment processing will be described with reference to the flowchart of FIG. First, the attribute information of the curve to be connected is read from the optimum processing order data table (FIG. 11B) (step 110), and it is checked whether or not it is a characteristic line (step 111). If any of the curves is a feature line, the point on the feature line where the curves are shortest is set as the intersection (step 112). If neither curve is a characteristic line, the contact point between the cross-section where the lower priority curve is in contact and the higher priority curve is the intersection (step 113).

Since the intersection point has been determined in the processing of step 112 or step 113, "variable offset conversion" is performed for each point sequence data of the curve with low priority (step 114). The calculation of this variable offset is based on the following formula.

[0065]

[Equation 1]

The intersections can be matched by performing the above processing.

In such intersection adjustment processing, a part of the curve having the lower priority is moved so that the intersections match. Due to this movement, the curve is deformed, and there is a risk that the shape of the curve will be changed significantly. Therefore, in this embodiment, the curve is smoothed after the intersection adjustment processing (step 82). Smoothing a curve is a process performed so that the change in the curvature of the curve becomes smooth.

By repeating the processing of the step 81 of creating the intersection and the step 82 of smoothing the curve from the curve of the higher priority to the curve of the lower priority,
A boundary wireframe model in which the intersections of all curves match is completed.

When the boundary wire frame model is completed in this way, the curved surface coefficients can be easily calculated for each of the surfaces already defined (step 83).

However, in order to complete a smooth curved surface model, the connection between curved surfaces must be considered. In the method of creating a curved surface model according to this embodiment, the curved surface feature data table (FIG. 21 (l) to FIG.
A surface to be connected for each curved surface defined in (n) and its connecting method, and a surface to be connected and its connecting method are used. Then, by referring to only the surface of which surface data has already been created, which has a higher priority than itself, and calculating the surface coefficient considering the connection on the boundary line with that surface, the smoothly connected products can be obtained. The curved surface model is completed.

The product curved surface model completed in this way is displayed on the screen, and the product shape designer confirms the difference from the actual product model while visually observing this screen (step 8).
4).

When there is a difference from the actual product model, the product shape designer selects either the correction of the curve or the change of the boundary line of the surface candidate. By this selection, the product curved surface model is corrected (step 85).

When the correction of the curve is selected, intersection adjustment and smoothing of the curve are performed so as to match the curve to be corrected with another curve. As a specific example, the priority is 1 to 1.
Considering a curved surface model composed of 10 curves up to 0, when a curve with a priority of 3 among these curves is modified, the priority of the curve to be modified becomes 11.
The priority of the optimum processing order data table (FIG. 11B) is changed. Since the priority of the modified curve is the lowest, the intersection point adjustment and the smoothing of the curve after the modification of the curve are performed by fixing the curves other than the modification target curve and then modifying the modification target curve to other curves. It is carried out to suit. Therefore, compared to the conventional example in which all the curves are readjusted,
The processing time can be shortened.

When the change of the boundary line of the surface candidate is selected, the readjustment is performed only on the curved surface including the boundary line affected by this change. This readjustment process is shown in FIG.
This will be described in detail using a specific example of No. 27B, the boundary lines 92 and 96 between the curved surface S ₁₂ and the curved surface S ₁₃ of the curved surface model composed of the curved surfaces S _{11 to} S ₁₄ as shown in FIG. When creating a curved surface model, first, a curve feature data table (FIG. 14E to FIG.
From (j)), information about the curved surface having the boundary lines 92 and 96 in part is read out. From this information, the borderline 92
It can be seen that the curved surfaces having a part of them are curved surfaces S ₁₁ , S ₁₂ , and S ₁₃ , and the curved surfaces having a boundary line 96 in a part thereof are curved surfaces S ₁₁ , S ₁₂ , and S ₁₃ . Therefore, after the boundary lines 92 and 96 are changed, only the curved surfaces S ₁₁ , S ₁₂ , and S ₁₃ need to be readjusted, so that the processing time can be shortened as compared with the conventional example in which the curved surface S ₁₄ is readjusted. Can be achieved.

The CAD device 2 used in this embodiment
0 is not limited to this configuration, and an optical disk device may be used instead of the hard disk devices 33 and 34, for example.

[0076]

According to the curved surface model creating method of the present invention,
The curve geometric data and curve management data created in the first step, the child surface management data created in the second step, and the curved surface geometric data created in the fourth step are
The relationship is managed by at least one common field.

In each step, by utilizing the data of this connection, it is possible to process at high speed with the minimum required data access. Therefore, the processing time of each step is significantly reduced.

[Brief description of drawings]

FIG. 1 is a flowchart showing an outline of a curved surface model creating method according to the present embodiment.

FIG. 2 is a block diagram showing a configuration of a CAD device to which the curved surface model creating method according to the present embodiment is applied.

FIG. 3 is a diagram showing a configuration of each table of data management D / B.

FIG. 4 is a diagram showing a configuration of each table of data management D / B.

FIG. 5 is a diagram showing a configuration of each table of data management D / B.

FIG. 6 is a diagram showing a configuration of each table of data management D / B.

FIG. 7 is a flowchart showing a detailed processing flow of a curved surface model creating method according to the present embodiment.

FIG. 8 is a diagram showing a simple example of a curved surface model created according to the present embodiment.

FIG. 9 is a diagram showing movement of data in each table of data management D / B.

FIG. 10 is a diagram showing movement of data in each table of data management D / B.

FIG. 11 is a diagram showing movement of data in each table of data management D / B.

FIG. 12 is a diagram showing movement of data in each table of data management D / B.

FIG. 13 is a diagram showing a movement of data in each table of data management D / B.

FIG. 14 is a diagram showing a movement of data in each table of data management D / B.

FIG. 15 is a diagram showing movement of data in each table of data management D / B.

FIG. 16 is a diagram showing a movement of data in each table of data management D / B.

FIG. 17 is a diagram showing movement of data in each table of data management D / B.

FIG. 18 is a diagram showing movement of data in each table of data management D / B.

FIG. 19 is a diagram showing movement of data in each table of data management D / B.

FIG. 20 is a diagram showing movement of data in each table of data management D / B.

FIG. 21 is a diagram showing movement of data in each table of data management D / B.

FIG. 22 is a diagram showing movement of data in each table of data management D / B.

FIG. 23 is a diagram showing movement of data in each table of data management D / B.

FIG. 24 is a diagram showing a movement of data in each table of data management D / B.

FIG. 25 is a diagram showing movement of data in each table of data management D / B.

FIG. 26 is a flowchart showing the logic of intersection adjustment processing.

FIG. 27 is a diagram showing a curved surface model adjusted by a readjustment process.

FIG. 28 is a flowchart showing an outline of a curved surface model creating method according to a conventional example.

[Explanation of symbols]

20 ... CAD device, 30 ... Host computer, 31 ...
Central processing unit, 32 ... Main storage device, 33, 34 ... Hard disk device, 35 ... Interface device, 36 ... Conversion device, 40-46 ... CAD terminal, 50 ... Three-dimensional shape measuring device, 60 ... Processing device.

Claims (6)

[Claims] 1. An input of point sequence data indicating point coordinates on a plurality of curves measured on the surface of an object to be measured is received, and the point sequence data is analyzed to create curve geometric data and curve management data. The first step is to divide the DUT into a plurality of child curved surfaces to create a wire frame, define the relationship between each curve and the child curved surface constituting the wire frame, and update the curve management data. A second step of creating child surface management data, and a third step of creating an optimal processing schedule for creating curved surface geometric data based on the relationship between the curve and the child surface defined in the second step. And a fourth step of creating curved surface geometric data of a child curved surface based on data of each curve forming the wire frame according to the processing schedule. Management data and geometric data and child curved surface, surface modeling method characterized by relationship ties in at least one common field is managed. 2. The curved surface model creating method according to claim 1, wherein the areas of the management data and geometric data of the curves and child curved surfaces created or updated in the processing of each step are dynamically created. . 3. The management data of the curve and the child surface is
3. The curved surface model creating method according to claim 1, wherein at least priorities of the curves and the child curved surfaces are managed. 4. The management data of the curve and child surface is
4. The curved surface model creating method according to claim 1, wherein at least a connection relationship between curves and child curved surfaces is managed. 5. The management data of the curve and the child surface is
The curved surface model creating method according to claim 1, wherein the relationship with at least a curve surrounding the child curved surface is managed. 6. The curved surface model creating method according to claim 1, further comprising a step of modifying the curved surface geometric data created in the fourth step.