JP2001273016A - Data processor and a memory medium readable by a computer - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a data processor by which a control data file for efficient NC machine control can easily be obtained from an engineering drawing file produced by a CAD program. SOLUTION: When determining a circular arc shape for representing a portion of a curve (S205-S210), the data processor determines a reference circle (S205) passing through three consecutive points included in a series of points upon the curve. Among the points located nearer the tails of the curve than these 3 points, the data processor identifies all points satisfying that both the point of interest and the previous point thereof are positioned in a region being located not more than a tolerance δ distant from the reference circle (S206-S209). The data processor determines an arc shape which can approximate an arc passing through the identified points as well as the 3 points used for determining the reference circle (S210).

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a data processing apparatus for generating a plurality of element data representing a set of several arcs and several line segments approximating a curve, and a computer. And a computer-readable recording medium for operating as a computer.

[0002]

2. Description of the Related Art In recent years, various types of design drawings (for example, design drawings of a printed circuit board, a ship, a building, and the like) have been created using a computer (CAD program). As is well known, the design drawing data created by the CAD program includes a plurality of graphic element data each representing a graphic element (circle, arc, line segment, curve, etc.) of a specific shape.

[0003]

In some fields, products are manufactured by directly inputting design drawing data created by a CAD program to a machine tool. However, such products are used in the manufacture of ships and the like. NC (numerical contro
l) The machine tool can perform only a linear motion (machining) or a circular motion. That is, an NC machine tool used for manufacturing a ship or the like cannot perform an operation corresponding to a curve graphic element included in design drawing data created by a computer. For this reason, conventionally, based on design drawing data (or design drawing) obtained by a CAD program, an operator (creator of control data) divides each curve and approximates each curve as an arc (or line segment). By specifying the division position,
Control data for the NC machine tool is created, and the NC machine tool is controlled by the control data.

[0004] The control data thus created is
Since the curved portion is often divided into arcs that are excessively finely divided, conventionally, the NC machine tool is inefficient, such that a portion that may be processed in one operation is processed in two operations. It was frequently used.

[0005] It is an object of the present invention to provide a data which can generate data having a small total number of elements, in which a curve having a shape other than an arc is represented by a combination of some arc elements and some line segment elements. A processing device, for example, CAD
Data processing for easily obtaining a control data file (a file containing a plurality of element data representing a curve) that can efficiently control an NC machine tool from a design drawing file (a file containing curve definition information) created by a program It is to provide a device.

Another object of the present invention is to provide a computer-readable recording medium for operating a computer as such a data processing device.

[0007]

According to the present invention, there is provided a data processing apparatus for generating a plurality of element data representing several arcs and several line segments approximating a curve. A coefficient of an equation representing a circle passing through a reference point group consisting of a point designated as a starting point and two subsequent points in a point sequence composed of a plurality of ordered points located on a curve; Alternatively, a coefficient calculating means for calculating a coefficient of an equation representing a straight line passing through the reference point group, and a preceding point and a point itself among the points on the tail side of the reference point group of the point series are used as the coefficient calculating means. A specifying means for specifying all points located in an area whose distance from a circle or a straight line represented by an equation whose coefficient is calculated is equal to or less than a specified value, and one or more points are specified by the specifying means. If
An arc or line segment that approximates the point group consisting of the one or more points and the reference point group, and that has, as an end point, the foremost point and the most end point in the point sequence in the point group. Is generated, and if no point is specified by the specifying means, the point at the forefront and the point at the end of the point series in the reference point group are defined as end points. Then, the generating means for generating element data representing an arc or a line segment passing through the remaining one point, and the coefficient calculating means functioning by designating the head point of the point series as a starting point, are used. Each time it is generated, the calculation is performed by using a calculation order control unit that causes the coefficient calculation unit to function by designating the end point on the end side of the arc or line segment represented by the element data as a start point.

That is, in the data processing device of the present invention,
In determining the shape of one arc representing a part of a curve to be processed, first, a circle (or a straight line) passing through three consecutive points (reference point group) included in a series of points located on the curve is considered. The coefficients of the equation are determined. Then, from the points on the tail side of the reference point group, all the points that are located within an area whose distance from the circle (or the straight line) is equal to or less than a specified value are identified. Then, the shape of the arc is determined so that the specified point and the reference point group can be approximated. At this time, the shape of the circular arc is such that the circular arc is continuous with the previous and subsequent circular arcs determined by the same procedure, and is included in a point group including one or more specified points and a reference point group. The point sequence is determined to have the foremost point and the last point in the point sequence as end points.

[0009] Since the shape of the arc is determined by such a procedure, the present data processing apparatus generates data (data consisting of several element data) obtained by approximating a curve with a small number of arcs. become. Therefore, according to the data processing device of the present invention, for example, a control data file (a plurality of curves representing a curve) capable of efficiently controlling an NC machine tool is obtained from a design drawing file (a file including curve definition information) created by a CAD program. File containing element data) can be easily obtained.

When the data processing apparatus of the present invention is realized as an apparatus capable of processing a general design drawing file, coordinates of each point constituting a point sequence are calculated based on function information representing a curve. It is necessary to add a coordinate calculation means.

In implementing the data processing apparatus of the present invention, when the radius of the arc approximating the point group exceeds a predetermined value, the generation means may be configured to be the first one in the point series in the point group. It is possible to use a means for generating element data representing a line segment whose end point is the end point of the point. By using such a generating means, it is possible to obtain a data processing device in which element data that cannot be used for controlling an NC machine tool or the like is not generated.

In implementing the data processing apparatus of the present invention, when one or more points are specified by the specifying means as the generating means, the data processing apparatus includes the one or more points and a reference point group. The coefficient of the equation of the circle passing through the point at the forefront and the point at the end of the point series in the point group is calculated for each point in the point group between the point and the center of the circle. A method is used in which the sum of square values obtained by subtracting the square value of the radius of the circle from the square value of the distance is minimized and element data representing an arc included in the circle for which the coefficient of the equation is obtained is adopted. It is desirable to do.

In other words, there are various possible configurations of the generating means (coefficient calculation procedure), but if a generating means having a configuration other than the above configuration is adopted,
It takes time to calculate the coefficient. Therefore, when implementing the data processing device of the present invention, it is desirable to employ the generating means having the above configuration.

The computer-readable recording medium of the present invention stores a program for causing a computer to operate as the data processing device of the present invention. Therefore, if the computer-readable recording medium of the present invention is used, for example, CAD
From the design drawing file created by the program, N
A control data file that can efficiently control the C machine tool can be easily obtained.

[0015]

Embodiments of the present invention will be described below with reference to the drawings.

A data processing apparatus 10 according to one embodiment of the present invention converts a design drawing file created by a CAD (Computer Aided Design) program into a control data file including control data for controlling an NC machine tool. It is a device to do.

As schematically shown in FIG. 1, the data processing apparatus 10 according to the embodiment stores a computer-readable recording medium in an HDD 34 in a computer 20 including a display 21, an input device 22, and a computer main body 23. This is realized by installing a conversion program 41 and a conversion condition information file 42 recorded on a certain CD-ROM 60 via a CD-ROM drive 36.

The conversion program 41 is stored in the computer 20
Is a program for operating as a data processing device 10. It should be noted that the conversion program 41 is a predetermined OS
Created as a program to be executed on
The OS is also installed in the DD 34.
The conversion condition information file 42 is a file holding the number of divisions n _D , the tolerance δ, and the maximum radius R _LMT which are information referred to by the conversion program 41. Although the use of each information will be described later, the conversion condition information file 42 has a value corresponding to the degree of the spline function included as the graphic element data in the design drawing file (2 of the degree) as the division number n _D.値 3 times) is stored (set). The maximum radius R _LMT is the NC used.
The maximum radius of the arc-shaped operation that can be executed by the machine tool is stored, and a value designating an error from an allowable design value is stored as the tolerance δ.

In the computer 20 (ie, the data processing device 10) on which the conversion program 41 has been executed, the CPU
Under the control of 31, the file conversion process of the procedure shown in FIG. 2 is executed. It should be noted that the conversion program 41 is configured so that the CPU 31 operating according to the OS notifies the input device 22 that an instruction to execute the conversion program 41 has been given from the operator.
It is executed by the CPU 31 when it is recognized via.

As shown in the figure, at the time of file conversion processing, first, the division number initial value n _D , tolerance δ and maximum radius R _LMT stored in the conversion condition file 41 are stored in the RAM 32.
The file is read out (step S101), and a file designation information acquisition process (step S102) is executed. At the time of this file designation information acquisition processing, a control for storing design drawing file designation information (drive name, folder name and file name) for designating a design drawing file to be processed, and a conversion result from the operator via the input device 22. Control data file specification information for specifying a data file is acquired. The file specification information acquisition process, the operator, RAM 32 above (or, RAM 32 and on the conversion condition information file 42) can change the division number initial value n _D, tolerance δ and maximum radius R _{LM T} of Processing. Therefore, when the operator wants the data processing device 10 to convert the file under a condition different from the normal condition,
In this step S102, an operation for changing the division number initial value n _{D and the} like is also performed on the input device 22.

After the completion of the file designation information acquisition process,
The design drawing file specified by the design drawing file specification information is opened for reading, and the control data file specified by the control data file specification information is opened for writing (step S103).

That is, when the drive name in the design drawing file designation information indicates the FDD (Flexible Disk Drive) 35, the design drawing file designation stored in the flexible disk 50 set in the FDD 35 is designated. The file identified by the folder name and file name in the information is opened. When the drive name in the design drawing file designation information indicates the HDD 34, the file identified by the folder name and the file name in the design drawing file designation information stored in the HDD 34 is Be opened. Further, when the drive name in the design drawing file designation information indicates a network drive, the communication control circuit 37 is used and the drive name of another computer connected by the LAN cable 70 is used. The file identified by the folder name and the file name in the design drawing file specification information stored in the identified drive is opened. Similarly, for the control data file, the file stored with the specified file name is opened at the location specified by the control data file specification information. However, regarding the control data file,
A new file is created and opened.

After opening the design drawing data file and the control data file, the first graphic element data in the design drawing file is read out (step S104), and the graphic element data is converted into a spline curve (a curve defined by a spline function). ) Is determined (step S105). If the read graphic element data does not represent a spline curve (step S10
5; NO), control data corresponding to the graphic element data,
That is, control data representing an arc or a line segment is created and added to the control data file (step S10).
6). On the other hand, if the read graphic element data represents a spline curve (step S105; YE
S), the data conversion process is repeated for each segment of the spline curve (steps S107, S10)
8; NO).

FIG. 3 shows a flowchart of the data conversion process in step S107. As shown in the figure, at the time of data conversion processing, first, “ _nd + 1” is set to a variable N (step S200). Then, one of the spline curves
Point series P ₁ to P on the curve for the segment (curve to be processed)
P _N of the coordinates _{(X 1, Y 1) ~} (X N, Y N) is calculated (step S201).

Specifically, in step S201,
First, the curve to be processed (one segment of the spline curve)
X = f (t), Y = g (t), t₁≦ t ≦ t_Two"
The function of the form is determined. Note that f (t) and g (t) are
Is the same as the spline function indicated by the graphic element data
Alternatively, it is a polynomial function of t of lower order.
t ₁, T_TwoIs (f (t₁), G (t₁)), (F (t_Two), G (t
_Two)) Is the coordinates of the end point (node) of the segment to be processed
Is a value

After determining the coefficients of f (t) and g (t), the coordinates (X _i , Y _i ) of the node obtained by equally dividing the curve to be processed in the parameter space t by (N−1) are obtained. That is, in the step S201, for example, when N is "5", as schematically shown in FIG. 4, the end points of the processing target curve, the points P _1, with including a point P _5, these N (= 3 points) including three points P _{2 to} P ₄ located on a curve connecting end points
5) Coordinates (X ₁ , Y ₁ ) to (X _N , Y _N ) of the point series P _{1 to} P _N
Is calculated.

After the calculation of the coordinates (X ₁ , Y ₁ ) to (X _N , Y _N ), the variable i for storing information (number) designating one point in the point series P _{1 to} P _N. “1” is set (step S2
02), “i + 2” is set as a variable j for storing information designating another point (step S203). Thereafter, when the j (= i + 2) value is equal to or smaller than the N value (step S204; YES), that is, at three points P _i , P _{i + 1} and P
_{If i + 2} exists, the center coordinates (x ₀ , y ₀ ) and radius r ₀ of the reference circle, which is a circle passing through these three points, are calculated by a series of arithmetic expressions (step S205). . In other words, in this step S205, (X, Y) = (X i, Y i),
For each of (X, Y) = (X _{i + 1} , Y _{i + 1} ) and (X, Y) = (X _{i + 2} , Y _{i + 2} ), the formula “(X−x ₀ ) ² + (Y -y ₀₎ ² -r ₀ ² =
X ₀ , y _0, and r ₀ that satisfy _{0 ”} are calculated.
If the three points P _i , P _{i + 1} and P _{i + 2} are located on a straight line (in this case, the reference circle is not obtained), step S20
In 5, the coefficients A, B, and C of the equation “AX + BY + C = 0” representing the straight line (hereinafter, referred to as a reference line) are calculated.

After the completion of step S205, "1" is added to the variable j (step S206). That is, a value indicating the next one of the three points used for determining the reference circle is set as the variable j. Then, it is determined whether or not the j value is equal to or less than the N value (step S207). If the j value is equal to or less than the N value (step S207; YES), the point _Pj and the reference circle or the reference line are determined. Is calculated and stored as a variable d (step S208). More specifically, when the reference circle has been demanded, (1) by equation of the distance d (the point P _j and a reference circle from the reference circle of the point P _j center (x _0, y ₀₎ and the The absolute value of the value obtained by subtracting the radius r _{0 of the} reference circle from the distance between them is obtained. If the reference line has been determined, (2)
The distance d of the point _Pj from the reference line is obtained by the equation.

[0029]

(Equation 1)

Thereafter, the calculated d value is compared with the set δ value (step S209). If the d value is not more than the δ value (step S209; YES), the processing from step S206 is performed. Is executed again.

If the d value calculated in step S208 exceeds the δ value (step S209; NO), the points P _{i and} P _j-1 are determined based on the coordinate information of the points P _{i to} P _j-1 . As described above, the center coordinates (Xc, Yc) and the radius R of a circle (hereinafter, referred to as an approximate circle) approximating each point from the point P _{i + 1} to the point P _j-2 are calculated (step S210). .

In the data processing device 10 according to the present embodiment, in step S210, the following (3)
The coefficients Xc, Yc and R of the function h (X, Y) defined by the equation
Is the sum of h (X _k , Y _k ) ² with respect to each integer k from “i + 1” to “j−2” (hereinafter, Σh (X _k , Y _k ) ² ) is minimized.

[0033]

(Equation 2)

Here, Xc, Yc and R satisfying the above conditions are satisfied.
The calculation procedure (principle) of will be briefly described. Above
From equations (4) and (5), for h (X, Y), h (X _i , Y _i )
_{-H (X j -1, Y j} -1) is = 0 holds. Therefore, the equation (6) not including R can be obtained. Also, using equation (4)
By transforming equation (3), equation (7) not including R can be obtained.

[0035]

(Equation 3)

Then, using equation (6), Yc
By _{erasing, X, Y, X i,} Y i, X j-1, Y j-1, and represented by Xc h (X, Y) can be obtained. (6),
Since both equations (7) are linear equations relating to Xc and Yc, h (X, Y) obtained in this way is a linear equation relating to Xc. On the other hand, the Xc value that minimizes Σh (X _k , Y _k ) ² is, as is well known, a function ∂Σh (X _k , Y _k ) ² / ∂Xc
Can be obtained by finding the Xc value at which the value of "." This ∂Σh (X _k , Y _k ) ² / ∂Xc is given by h (X, Y)
Because ² is quadratic in _{Xc, (X i, Y i} ) ~ (X j-1, Y j-1)
Is a linear expression of Xc having a coefficient that can be uniquely calculated from

In step S210, Xc, Yc
And R have been calculated. Although the detailed description is omitted, the distance between the approximate circle specified by Xc, Yc and R calculated in this way and any point _{Pk in} the points Pi _{+ 1 to} Pj _-2 Is δ regardless of the positional relationship between the points P _{i to} P _j-1.
It is as follows.

When step S210 is executed in a state where j = i + 3 holds (step S205).
In step S209 executed immediately after the execution of
O ”side), Δh (X _k , Y _k ) ²
Xc, Yc and R obtained from the coefficient of / ∂Xc are respectively equal to x ₀ , y ₀ and r ₀ . Therefore, step step S210, if the j = i + 3 is performed in a state in which satisfied, where x ₀ value at that time, y ₀ value and r ₀ value, respectively, Xc, is set to Yc and R It has become. Step S210 determines whether the point P
_{When i to} P _j-1 are on a straight line (when the center coordinates of the approximate circle cannot be calculated), the coefficient of the equation representing the straight line calculated in step S205 is directly used as the calculation result. It is with.

The calculation result of step S210 is used for creating control data in the following step S211. Specifically, when the center coordinates and the radius of the approximate circle have been determined in step S210, the process proceeds to step S211.
Then, control data representing the arc of the approximate circle, in which the point P _i is one end point and the point P _j-1 is the other end point, is created and added to the control data file. However, if the calculated radius R is larger than the maximum radius R _LMT ,
In step S211, not the control data representing the arc but the control data representing the line segment where the point P _i is the start point and the point P _j-1 is the end point are added to the control data file. Further, even when the calculated result of step S210 is a coefficient of linear equations, in the step S211, a point P _i is the starting point, the point P _j-1 is the control data representing the line segment which is the end point control data Appended to the file.

After adding the control data, “j−
1 "(the number of the last point of the points P _{i to} P _j-1 for which the control data has been created this time) is set (step S212), and the processing from step S203 is executed again.

Steps S206 to S209 for a certain i value are obtained as a result of repeating the processing of such a procedure.
When the j value exceeds the N value during the execution of (Step S20)
7; NO), processes having the same contents as those in steps S210 and S211 (steps S220 and S221) are executed, and the data conversion process ends. That is, step S205
When the point P _{i + 2} used to determine the reference circle in is the last point (when j = i + 2 = N holds when the step S203 is completed), or when the distance is determined in the step S208. When the point P _j at which d is calculated is the last point, control data relating to points P _{i to} P _j-1 (= P _N ) is created and added to the control data file. Then, since the processing for all points related to the processing target curve (spline curve for one segment) has been completed, the data conversion processing ends.

When the value of the variable j reset at step S203 exceeds the N value (step S203).
204; NO), the N value is incremented by "1" (step S230), and the processing from step S201 is executed again.

That is, the processing of step S212 and the subsequent step S203 is performed by setting the number of the last point of three or more points for which control data has been created in the variable i, and then setting the variable to the N value or less. This is processing for incrementing the value of the variable j that has occurred (the branch to the “YES” side has been made in step S207) by “1”. Therefore,
In step S204, the branch to the “NO” side is performed when j = N is satisfied at the time of execution of step S212, that is, when only one point where no control data is created remains. It is. In this case, the point P
It is also possible to create control data representing a line segment where _N-1 is the start point and the point _PN is the end point and add it to the control data file. However, in this apparatus, the number of divisions is increased and recalculation is performed. It is.

Here, the processing procedure in the data conversion processing will be described more specifically with reference to FIGS. It should be noted that the curves shown in these figures show the leading part of the curve for one segment of the spline function (n _d > 10).

First, as shown in FIG. 5, the center coordinates (x ₀ , y ₀ ) and the radius r _{0 of the} circle passing through the points P _{1 to} P ₃ are obtained by the processing of steps S200 to S205. That is, the coordinate calculation means (step S201) and the calculation order control means (step S202) included in the data processing device 10
And coefficient calculating means (steps S203 to S205) function.

Thereafter, the processing of step S206 to S209, it is determined the distance d from the reference circle of the point P _4,
It is determined whether d ≦ δ is satisfied. In it is illustrated case, since the smaller d value than δ value for the point P ₄ is determined, branching to "YES" side in Step S209 is performed. As a result, the distance d from the reference circle of the point P ₅ and the tolerance δ are compared. And the point P ₅ becomes
Since the point is at least δ away from the reference circle, step S
At 209, a branch is made to the "NO" side. In other words, certain means serve the data processing apparatus 10 is provided, the point P ₄ is identified.

[0047] Consequently, step S210 is executed, as is shown in FIG. 6, the point P ₁ and the center coordinates of the approximate circle passing through the point P ₄ (Xc, Yc) and the radius R is determined. Then, on the approximation circle, the control data indicating the arc that the point P ₁ and point P ₄ and the end point is created and stored in the control data file. That is, the generation unit included in the data processing device 10 functions.

Thereafter, in step S212, "4" (= j-1; j = 5 at this time) is set as a variable i. That is, the function as the calculation order control means provided in the data processing device 10 is executed. As a result, the processing of step S202 to S205, as shown in FIG. 7, the equation of the reference circle passing through the point P ₄ to P ₆ are obtained.
Then, the processing of step S206 to S209, that its distance from the reference circle are continuous in one or more or less δ is searched from the points following the point P ₄ to P _6. In this case, the points P ₇ and P ₈ are points whose distance from the reference circle is δ or less, and the point P ₉ is a point whose distance from the reference circle exceeds δ. Step S210 is performed. As a result, as shown in FIG. 8, the points P ₄ and P ₈
It determines the approximate circle passing bets, on the approximation circle, the control data indicating the arc that the point P ₄ and the point P ₈ and the end point is created and stored in the control data file.

At the time of this data conversion processing, such processing is repeated, and some arcs (or some arcs and some line segments) approximating the curve to be processed (one segment spline curve) are formed. It is determined and a control data group corresponding to them is set in the control data file.

Returning to FIG. 2, the description of the file conversion process will be continued. When the processing for all the segments of the spline curve is completed (Step S108; YES), or after the end of Step S106, it is determined whether or not the processing of all the data in the design drawing file is completed (Step S109). . When processing of all data has not been completed
In (Step S109; NO), the next graphic element data in the design graphic file is read (Step S110),
The processing from step S105 is executed again on the graphic element data.

When the processing of step S106 or the processing of steps S107 and S108 is completed for all the graphic element data (step S109; YES), the design drawing file and the control data file are closed. (Step S111), the file conversion process ends.

As described in detail above, according to the data processing apparatus 10 of the present embodiment, based on a design drawing file relating to a graphic using a spline curve, the graphic is formed by a combination of arcs and line segments. A represented control data file can be generated. Further, in the present data processing device 10, the total number of arcs can be as small as possible under the condition that the combination of arcs (or the combination of arcs and line segments) approximating the spline curve has an error from the design value equal to or smaller than the tolerance δ. It is determined to be less (so that one arc approximates the wider part of the curve). Therefore, according to the data processing device 10, the NC drawing is performed from the design drawing file created by the CAD program.
It is possible to easily obtain a control data file that can efficiently control the machine tool.

<Modification> The data processing apparatus 10 described above
Can be variously modified. For example, the data processing device 10 is a device that processes a curve represented by a spline function, but can process a curve or a Bezier curve represented by another type of function (a trigonometric function or a simple polynomial). The data processing device 10 may be modified as described above. Further, the data processing apparatus 10 may be modified so as to process a curve represented by a plurality of point coordinates (a curve represented by a plurality of connected line segments) instead of a function.

If the branch to the “NO” side is made in step S204, an approximate circle passing through the points P _i and _PN is obtained, and the points P _i and P _N
Is the control data added to the control data file in the immediately preceding step S211 (the control data representing an arc having two end points P _i and P _N-1). ), The data processing device 10 may be configured so as to be stored in a control data file and to end the data conversion process. At the time of the branch, the coordinates of some points on the curve between the points P _N−1 and P _N are obtained, and the points P _{N− 1,} the data conversion process creates the control data representing an arc or the like for approximating the curve between points P _N may be set to the be terminated.

The data processing device 10 according to the embodiment
Then, when calculating the coefficients of the equation of the approximate circle, Σh (X _k ,
Although the condition that Y _k ) ² (see equation (3)) is minimized is used, other conditions can be used when obtaining the coefficients of the equation of the approximate circle. For example, Σ | h (X _k ,
By using the condition that Y _k ) | is minimized, the coefficients of the equation of the approximate circle can be obtained. Also, | h (X _{i + 1} , Y
Using the condition that the maximum value among _{i + 1} ) | to | h (X _j-2 , Y _j-2 ) | Further, Σ | SQR ((X _k −Xc) ² + (Y _k −
Yc) ² ) -R | is minimum, or | SQR
((X _{i + 1} −Xc) ² + (Y _{i + 1} −Yc) ² ) −R | to | SQR ((X _j−2
Using the condition that the maximum value of −Xc) ² + (Y _j−2 −Yc) ² ) −R | is minimized, the coefficient of the equation of the approximate circle can be obtained. However, when these conditions are used, more operations are required to obtain the coefficients of the equation of the approximate circle than when the condition that Σh (X _k , Y _k ) ² is minimum is used. Will be. Therefore, when it is desired to convert a file at high speed, it is desirable to adopt the configuration of the data processing device 10 according to the embodiment.

[0056]

According to the data processing apparatus of the present invention, a plurality of element data representing several arcs and some line segments approximating a curve to be processed is reduced in total number of element data. And so on. Therefore, by using the data processing device of the present invention, for example, a control data file that can efficiently control an NC machine tool can be easily created from a design drawing file created by a CAD program. According to the computer-readable recording medium of the present invention, a computer can be operated as the data processing device of the present invention.

[Brief description of the drawings]

FIG. 1 is a diagram of a data processing device according to an embodiment of the present invention.

FIG. 2 is a flowchart of a file conversion process executed by the data processing device according to the embodiment.

FIG. 3 is a flowchart of a data conversion process executed during a file conversion process.

FIG. 4 is an explanatory diagram of a data conversion process.

FIG. 5 is an explanatory diagram of a data conversion process.

FIG. 6 is an explanatory diagram following FIG. 5 of the data conversion process;

FIG. 7 is an explanatory diagram following FIG. 6 of the data conversion process;

FIG. 8 is an explanatory diagram following FIG. 7 of the data conversion process;

[Explanation of symbols]

 Reference Signs List 10 data processing device 20 computer 21 input device 22 display 23 computer main body 31 CPU 32 RAM 34 HDD 35 FDD 36 CD-ROM drive 37 communication control circuit 41 conversion program file 42 conversion condition information file 50 flexible disk 60 CD-ROM 70 LAN cable

Claims (8)

[Claims] 1. A data processing device for generating a plurality of element data representing some arcs and some line segments approximating a curve, comprising a plurality of ordered points located on the curve. Of the equation representing a circle passing through a reference point group consisting of a point designated as a starting point and two succeeding points, or an equation representing a straight line passing through the reference point group, in a point sequence to be executed. Coefficient calculating means for calculating a coefficient, from among the points on the tail side of the reference point group of the point series,
A specifying means for specifying all points located in an area whose distance from a circle or a straight line represented by an equation whose coefficient has been calculated by the coefficient calculating means is equal to or less than a predetermined value, and When one or more points are specified by the specifying unit, a point group including the one or more points and the reference point group is approximated, and the point series in the point group in the point group is approximated. Generating element data representing an arc or a line segment having the foremost point and the last point as end points, and if no point is specified by the specifying means, the reference point group Generating means for generating element data representing an arc or a line segment passing through the remaining one point, having the foremost point and the last point in the point series as end points, Specify the first point of The coefficient calculation means is caused to function, and each time element data is generated by the generation means, the end point on the end side of the arc or line segment represented by the element data is designated as a start point to function the coefficient calculation means. A data processing device comprising: a calculation order control unit that causes the calculation order to be controlled. 2. The data processing apparatus according to claim 1, further comprising: a coordinate calculating unit configured to calculate coordinates of each point constituting the point sequence based on the function information representing the curve. 3. The method according to claim 1, wherein when the radius of the arc approximating the point group exceeds a predetermined value, the generation unit determines a point at the forefront and a point at the most end in the point series in the point group. 3. The data processing device according to claim 1, wherein the data processing device generates element data representing a line segment that is an end point. 4. 4. The method according to claim 1, wherein, when one or more points are specified by the specifying unit, the generation unit includes a point group in the point group including the one or more points and the reference point group. The coefficient of the equation of the circle passing through the point at the forefront and the point at the back end is calculated from the square value of the distance between the point and the center of the circle for each point in the point group. The sum of the squared values of the values obtained by subtracting the squared values of the radius is calculated so as to be minimum,
4. An element data representing an arc included in a circle for which a coefficient of an equation is obtained is generated.
The data processing device according to any one of the above. 5. An apparatus for generating a plurality of element data representing a number of arcs and a number of line segments approximating a curve, the apparatus comprising: a plurality of ordered points located on the curve; A coefficient of an equation representing a circle passing through a reference point group consisting of a point designated as a starting point and two succeeding points, or an equation representing a straight line passing through the reference point group, in the constructed point sequence. Coefficient calculating means for calculating the coefficient of, from among the points on the tail side of the reference point group of the point series,
A specifying means for specifying all points located in an area whose distance from a circle or a straight line represented by an equation whose coefficient has been calculated by the coefficient calculating means is equal to or less than a predetermined value, and When one or more points are specified by the specifying unit, a point group including the one or more points and the reference point group is approximated, and the point series in the point group in the point group is approximated. Element data representing an arc or a component having the foremost point and the last point as end points is generated, and if no point is specified by the specifying means, the reference point group Generating means for generating element data representing an arc or a line segment passing through the remaining one point, having the most point and the last point in the point sequence as end points; Specify the first point as the starting point The coefficient calculation means is caused to function, and each time element data is generated by the generation means, the end point on the end side of the arc or line segment represented by the element data is designated as a start point to function the coefficient calculation means. A computer-readable recording medium on which a program for operating as a device including a calculation order control unit for causing the computer to operate is recorded. 6. The program causes the computer to operate as an apparatus further including coordinate calculation means for calculating coordinates of each point constituting the point series based on function information representing the curve. 6. The computer-readable recording medium according to claim 5, wherein: 7. When the radius of an arc approximating the point group exceeds a predetermined value, the generation unit determines a point at the forefront and a point at the most end in the point series in the point group. 7. The computer-readable recording medium according to claim 5, wherein the element data represents a line segment which is an end point. 8. The method according to claim 1, wherein, when one or more points are specified by the specifying unit, the generation unit determines the point sequence in the point group in the point group including the one or more points and the reference point group. The coefficient of the equation of the circle passing through the point at the forefront and the point at the back end is calculated from the square value of the distance between the point and the center of the circle for each point in the point group. The sum of the squared values of the values obtained by subtracting the squared values of the radius is calculated so as to be minimum,
8. An element data representing an arc included in a circle for which a coefficient of an equation is obtained is generated.
A computer-readable recording medium according to any one of the above.