JP3459155B2 - Compression processing method of machining shape data in shape machining system - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a shape processing for compressing processed shape data in order to process a material to be processed into a desired shape at high speed by a shape processing machine such as a three-dimensional cutting machine or a cutting plotter. The present invention relates to a method of compressing processed shape data in a system.

[0002]

2. Description of the Related Art Conventionally, when a material to be processed is processed into a desired shape by a shape processing machine such as a three-dimensional processing machine or a cutting plotter, compression such as deletion of unnecessary point data and unnecessary line segment data is performed. The processed shape data subjected to the processing is used. As a method of the compression processing, for example, it is known to replace a plurality of continuous line segments in the same straight line section with one line segment. Such a data compression processing method is disclosed in JP-A-3-230201.

A method of compressing processed shape data disclosed in Japanese Patent Laid-Open No. 3-230201 will be described with reference to FIG. First, an arbitrary point on one path is set to the start point P0.
And the "straight line distance" C of the parameter in a fixed direction on the starting point
A straight line l0 is drawn between the closest points P1 apart from each other. Next, consider two straight lines l1 and l2 which are translated from the straight line l0 to the left and right by a half of the "linear width" D of the parameter,
The points included in the straight lines l1 and l2 are deleted. P2 which is the farthest from the starting point P0 among the points deleted next
Is restored, and the processing similar to the above is repeated starting from the point P2. Here, the "straight line distance" C is set as the minimum value of the distance between the points, for example, 1 mm, and the "straight line width" D is set within the allowable range of the machining accuracy.

According to the method for compressing processed shape data, a plurality of line segments in the same straight line section can be replaced with one line segment.

[0005]

However, the above-mentioned method for compressing processed shape data has a problem that the data compressing process takes time because the process for detecting the same straight line section is complicated.

The "linear width" D must be set appropriately according to the size of the shape to be machined, which is very troublesome for the operator.

Further, as shown in FIG. 9, a certain starting point P0
From the point P2 to the point P3 and return to the point P3 in the vicinity of the point P0. If there are a plurality of wasteful (abnormal) line segments in the same straight line section, if the above compression processing method is used,
Unnecessary points P1 and P3 in the same straight line section are deleted,
The starting point P0 and the farthest point P2 are connected by a straight line, and then the point P2 is used as a starting point and processing is performed for points after the point P4.

As described above, the compression processing method cannot eliminate the folded straight line returning to the vicinity of the starting point in the same straight line section. Therefore, when the processing is performed according to the data processed here, unnecessary cuts are made in the material to be processed. It will cause troubles such as entering.

The present invention has been made in view of such circumstances, and an object thereof is to set machining shape data by a simple and high-speed method without setting parameters according to the size of the machining shape. It is an object of the present invention to provide a method for compressing processed shape data in a shape processing system, which is capable of reliably eliminating a line segment that becomes a useless (abnormal) path by compressing the.

[0010]

In order to achieve the above object, a method of compressing machining shape data in a shape machining system according to the present invention relates to machining shape data composed of n continuous line segments. , S (1 to n-1) to Sj due to the similarity of the linear coefficients of each line segment S (1 to n).
It is determined whether or not (j: i + 1 to n) are in the same straight line section, and continuous line segments Si (i: 1 to n-1) to Sj (j: i + 1 to n) are the same straight line. If it is determined to be in the section, the line segment Si (i: 1 to n-1)
The starting point of Sj (j: i + 1 to n) and the end point of Sj (j: i + 1 to n) are connected by a straight line to form a new line segment, and line segments Si (i: 1 to n-1) to Sj (j: i + 1 to n) I am trying to erase.

In the method of compressing processed shape data,
For example, when the line segment S1 is represented by a function of Z = aX + b, and the line segment S2 continuous to the line segment S1 is represented by a function of Z = a'X + b ', and the linear coefficient a≈a', If there is similarity and it is determined that the line segment S1 and the line segment S2 are in the same straight line section, and there is no straight line coefficient a≈a ', there is no similarity and the line segment S1 and the line segment S2 are not in the same straight line section. Is determined. If it is determined that the line segment S1 and the line segment S2 are in the same straight line section by the above determination, a new line segment is formed by connecting the start point of the line segment S1 and the end point of S2 with a straight line, and the line segment S1
And the line segment S2 is deleted.

Regarding the similarity, a constant δ1 representing the similarity of the linear coefficient may be set in advance, and the linear coefficient a'may be similar when the linear coefficient a'is within the range of a ± δ1.

Further, instead of the constant δ1, the constant θ1 of the angle element is set in advance, and in the relationship between the angle element θ of the linear coefficient a and the angle element θ ′ of the linear coefficient a ′, the above θ If'is within the range of θ ± θ1, it may be judged that there is similarity.

Further, instead of the constant δ1, a trigonometric function value constant γ1 is set in advance, and the linear coefficient a is si.
When the trigonometric function value γ of nθ or cos θ is used and the linear coefficient a ′ is expressed using the trigonometric function value γ ′ of sin θ ′ or cos θ ′, the trigonometric function value γ and the trigonometric function value γ ′ are obtained. In this relationship, if the trigonometric function value γ ′ is within the range of γ ± γ1, it may be determined that there is similarity.

As described above, in the method of compressing processed shape data in the shape processing system according to the present invention, the same straight line section can be searched for by a simpler and faster method than the conventional search for the same straight line section. Therefore, the time required for the data compression processing is short.

Further, a constant δ representing the similarity of the above linear coefficients
1 (θ1 or γ1) does not set specific dimensional values such as "straight line distance" C and "straight line width" D, which are the parameters of the conventional data compression processing method, but the inclination of each line segment and each Since the angle with respect to the axis is set, it is not necessary to change it according to the size of the shape to be machined.

Further, in the method of compressing processed shape data according to the present invention, continuous line segments Si (i: 1 to n) to Sj (j: i + 1 to).
If n) is determined to be in the same straight line section, a new line is created by connecting the start point of the line segment Si (i: 1 to n) and the end point of Sj (j: i + 1 to n) with a straight line. And line segments Si (i: 1 to n) to Sj (j: i + 1
.., n) are deleted, all the plural line segments that are wasteful (abnormal) paths that go from P0 to point P2 and return to point P3 near point P0 as shown in FIG. It is determined that they are in the same straight line section, and the points P0 and P3 are connected and then erased. In this way, useless (abnormal) line segments that were not erased by the conventional data compression processing method are certainly erased.

[0018]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, the present invention will be described with reference to the drawings. FIG. 1 is a system configuration diagram showing a specific example of a three-dimensional shape processing system for realizing the present invention, and FIG. 2 is an explanatory diagram explaining a processing example by the three-dimensional shape processing system shown in FIG. In the figure, reference numeral 1 denotes a three-dimensional shape data storage unit, which stores data expressing a target three-dimensional shape 2. Reference numeral 3 denotes an offset shape calculation unit, which reads the three-dimensional shape data D1 from the three-dimensional shape data storage unit 1,
Offset shape data D2 by the cutting tool 4 is created based on the data D1 and is stored in the three-dimensional shape data storage unit 1
Save to.

Reference numeral 5 denotes a cutting surface shape calculating unit which reads the offset shape data D2 from the three-dimensional shape data storage unit 1 and based on the data D2 a continuous line segment 6'indicating a tool path 6 for each cutting surface. The calculated shape data D3 is created and stored in the processed shape data storage unit 7. A machining shape data compression unit 8 reads machining shape data D3 from the machining shape data storage unit 7, creates machining shape data D4 compressed based on the data D3, and stores it in the machining shape data storage unit 7. To do. In the processed shape data compression unit 8, in the continuous line segment A in the same straight line section,
A new line segment connecting the start point and the end point of the continuous line segment is created, and the line segment A is deleted. Further, similar compression processing is also performed on the continuous folded line segment B in the same straight line section.

A machining shape data generation unit 9 reads the compressed machining shape data D4 from the machining shape data storage unit 7 and creates final machining shape data D5 based on the data D4 by eliminating tool interference and the like. Then, it is stored in the machining shape data storage unit 7. A machining shape data output unit 10 reads the final machining shape data D5 and outputs the data D5 to the three-dimensional cutting machine 11. The offset shape calculation unit 3, the cut surface shape calculation unit 5, the processed shape data compression unit 8, the processed shape data generation unit 9, and the processed shape data output unit 10 each include a ROM having an execution program, The common CPU executes the execution program.

FIG. 3 is a flow chart showing the data compression processing procedure of the processed shape data compression unit 8. Next,
A process of compressing the processed shape data D3 composed of n line segments S (1 to n) will be described with reference to FIG. Here, the line segment currently being processed is the line segment Si (i: 1 to n)
And the line segment after that is defined as a line segment Sj (j: i + 1 to n).

First, in step 1, the line segment Si (i: 1
N of i is set to 1. Next, in step 2, the line segment Si is represented by a function of Z = aX + b, and linear coefficients a and b are obtained. Next, in step 3, i + 1 is set to j. Then, in step 4, the line segment Sj is changed to Z =
It is expressed by a function of a'X + b ', and linear coefficients a'and b'are obtained.

Next, in step 5, the relation between the straight line coefficient a of the line segment Si and the straight line coefficient a'of the line segment Sj is a≈
It is determined whether or not it is a ', that is, whether or not the line segment Si and the line segment Sj are in the same straight line section. Here, a≈a ′ is a−δ1 ≦ a ′ ≦ a + δ1, and the above δ1 is a preset constant representing the similarity of linear coefficients. The constant δ 1 is preferably about 1.0 × 10 ^-6 .

If the determination result of step 5 is NO, the process proceeds to step 8. If the determination result of step 5 is YES, j + 1 is set to j in step 6. Then, in step 7, whether j> n, that is, the line segment Sj
Is not present.

If the determination result in step 7 is YES, the process proceeds to step 8, and if the determination result in step 7 is NO, the process returns to step 4. As a result, the similarity between the line segment Si and the new line segment Sj is determined again.

In step 8, whether j> i + 1,
That is, it is determined whether or not the line segment Sj is a line segment subsequent to the line segment Si. If the determination result of step 8 is NO, the process proceeds to step 11, and the determination result of step 7 is Y.
If ES, go to step 9.

In step 9, the starting point of the line segment Si and the starting point of the line segment Sj are connected by a straight line. That is, the start point of the line segment Si and the end point of the last line segment Sj-1 determined to be in the same straight line section as the line segment Si are connected to create new line segment data. Next, at step 10, the line segment data from the line segment Si to the line segment Sj-1 is erased.

In step 11, j of the line segment Sj is set to i
And set. Then, in step 12, whether i> n, that is, the new line segment S set in step 11
Determine if i does not exist. If the determination result in step 11 is NO, the process proceeds to step 2 and a new line segment Si
Is processed. If the decision result in the step 11 is YES, the compression process for the machining shape data D3 is ended.

FIGS. 4 and 5 show an example of compression processing of the processed shape data D3. First, in the line segments S1 to Si + 2 shown in FIG. 4A, Si: Z = a0X, respectively.
+ B0, Si + 1: Z = a1 X + b1, Si + 2: Z = a2 X +
It is expressed by the function of b2, and the relationship of these linear coefficients is a0
≈a1 ≈a2. In this case, according to the above compression processing, the line segments S1 to Si + 2 are regarded as the same straight line segment, a new line segment is created by connecting the start point P0 and the end point P1 of the same segment with a straight line, and the original line segment S1 to Erase Si + 2. Therefore, instead of being composed of three line segments S1 to Si + 2, it is composed of one line segment as shown in FIG. 4 (b).

Next, the folded line segment S shown in FIG.
In i to Si + 3, Si: Z = a00X +, respectively.
b00, Si + 1: Z = a01 X + b01, Si + 2: Z = a02 X
+ B02, Si + 3: Z = a03 X + b03,
The relationship between these linear coefficients is a00 ≈ a01 ≈ a02 ≈ a03
Has become. In this case, according to the above compression processing, the line segments S1 to Si + 3 are regarded as the same straight line section, a new line segment is created by connecting the start point P0 and the end point P1 of the same section with a straight line, and the original line segment S1 to Erase Si + 3. Therefore, there is no useless folded portion, and that portion is composed of one short line segment as shown in FIG.

In the above specific example, the XZ plane is used as the cutting plane, but the YZ plane may be used. In this case, the function representing the line segment is Z = aY + b
And so on.

Next, another specific example in which the similarity of the linear coefficients is determined based on the angle element θ of the linear coefficients will be described with reference to FIG. The above-described determination of the similarity of the straight line coefficient is performed by simply comparing the value of the slope of the line segment Si (the straight line coefficient a) with the value of the slope of the line segment Sj (the straight line coefficient a '). In each line segment Si to Si + 2, as shown in Fig. 4, the angles θi to θi + at which the X axis intersects with each line segment.
2 may be obtained, and if the angles are θi≈θi + 1≈θi + 2, it may be determined that the line segments Si to Si + 2 are in the same straight line section.

That is, a constant .theta.1 representing the similarity of the linear coefficients is set in advance, the line segment Si is represented by a function of Z = aX + b, and the line segment Sj (j: i + 1 ... n)
Is expressed as a function of Z = a'X + b ', the crossing angle θi and the crossing angle θj with the X axis are obtained in the line segment Si and the line segment Sj shown by the above function, and the angle θi and the angle When θj is within the range of θi ± θ1 in relation to θj, it is determined that the line segment Si and the line segment Sj are in the same straight line section. The function Z indicating the above line segment
= AX + b is Z = tan θX + b, and this angle θ may be used for comparison.

The above function Z = aX + b is Z = sin
It can also be expressed as θX / cos θX + b. Therefore, the similarity of the linear coefficient a may be determined by comparing the sin θ value or the cos θ value.

That is, a constant γ1 representing the similarity of the straight line coefficients is set in advance, the line segment Si is represented by a function of Z = aX + b, and the line segment Sj (j: i + 1 ... n)
Is expressed by a function of Z = a′X + b ′, the linear coefficient a is expressed by using a trigonometric function value γ of sin θ or cos θ, and the linear coefficient a ′ is sin θ ′ or cos θ ′.
When expressed using the trigonometric function value γ ′ of, in the relationship between the trigonometric function value γ and the trigonometric function value γ ′, if the trigonometric function value γ ′ is within the range of γ ± γ1, It is determined that the line segment Si and the line segment Sj are in the same straight line section.

Up to this point, regarding the method of determining the similarity of the straight line coefficient, the method of comparing the values of the straight line coefficient a, the method of comparing the angle element θ in the straight line coefficient a, the trigonometric function value in the straight line coefficient a (sin θ value or cos θ) The values are compared. As a characteristic of the above, the arithmetic processing can be performed in a short time, but when the line segments are substantially vertical, the values of a and a ′ are near ∞, and it is determined that there is almost no similarity. Since and are used to compare the similarity of line segments based on the angle element θ and the value of sin θ, the inclination of the line segment does not make it difficult to determine the similarity, but the calculation processing time becomes longer. .

Therefore, by using the above-mentioned methods in combination,
You may make good use of each characteristic. For example, in FIG.
As shown in, when the value of the linear coefficient a is 1.0 or less (the intersection angle θb of the X-axis and the line segment is 45 ° or less), the above determination method is used and the value of the linear coefficient a is 1.0 or less. Greater than (X
If the intersection angle θb between the axis and the line segment is larger than 45 °), the above determination method or the above determination method may be used.

Although the specific examples described so far show the data compression method of the machining shape data used in the three-dimensional machining machine, the present invention is not limited to this.
It can be adopted as a data compression method of two-dimensional processed shape data used for a cutting plotter or the like. In this case, the function representing the line segment is Y = aX + b.

[0039]

The present invention is carried out in the form as described above, and has the following effects.

In the method of compressing processed shape data in the shape processing system according to the present invention, it is determined whether or not consecutive line segments are in the same straight line section based on the similarity of the straight line coefficients of the respective line segments, and the above continuous When it is determined that the line segment is in the same straight line section, the start point and the end point of the continuous line segment are connected by a straight line to form a new line segment, and the continuous line segment is erased. According to the present invention, even with such a simple method, the machining shape data can be compressed at high speed to reliably eliminate the line segment that becomes a useless (abnormal) path.
Also, in order to determine whether or not consecutive line segments are in the same straight line section, it is determined by examining the similarity of the straight line coefficient of each line segment, so setting of parameters according to the size of the processed shape It is extremely practical without requiring.

[Brief description of drawings]

FIG. 1 is a system configuration diagram showing a specific example of a three-dimensional shape processing system that realizes the present invention.

FIG. 2 is an explanatory diagram illustrating a processing example by the three-dimensional shape processing system shown in FIG.

FIG. 3 is a flowchart showing a data compression processing procedure of a processed shape data compression unit shown in FIG.

FIG. 4 is an explanatory diagram illustrating an example of a compression process of processed shape data (a plurality of line segments are on a straight line).

FIG. 5 is an explanatory diagram illustrating an example of a compression process of processed shape data (a plurality of folded line segments are on a straight line).

FIG. 6 is an explanatory diagram illustrating another specific example of determination of similarity of linear coefficients.

FIG. 7 is an explanatory diagram illustrating a specific example using a plurality of methods for determining the similarity of linear coefficients.

FIG. 8 is an explanatory diagram illustrating a conventional method of compressing processed shape data (a plurality of line segments are on a straight line).

FIG. 9 is an explanatory diagram illustrating a conventional method of compressing processed shape data (a plurality of folded line segments are on a straight line).

[Explanation of symbols]

a, b Linear coefficient D3 machining shape data P0 start point P1 end point Si line segment Line segment following Sj Si δ1, θ1, γ1 A constant that represents the similarity of linear coefficients 8 Machining shape data compression unit

Claims (3)

(57) [Claims] 1. A machining shape data configured by the machining shape data storage unit has been a plurality of successive stored in line processing type
A method for compressing processed shape data in a shape processing system in which a shape data compression unit performs compression processing, and the shape processing machine is operated using the compressed processing shape data to process the material to be processed into a target shape. Therefore, the compression processing by the processing shape data compression means reads the processing shape data from the processing shape data storage unit.
A step of writing, by the similarity of linear coefficients of each segment, determining whether successive segments is in the same straight line segment, if the continuous line segment is determined to be in the same straight line section , A step of erasing the continuous line segment by connecting the start point and the end point of the continuous line segment with a straight line to form a new line segment
And the data representing the new line segment as the machining shape data
And storing it in the machining shape data storage unit.
And determine whether the above-mentioned continuous line segments are in the same straight line section
The step of setting a constant δ1 that represents the similarity of the above-mentioned linear coefficients is set in advance .
And a line segment Si, Z = aX + b, Z = aY + b or Y =
It is expressed by a function of aX + b, and the line segment Sj (j: i following the above line segment Si.
+1 to n) is represented by a function of Z = a'X + b ', Z = a'Y + b' or Y = a'X + b ', and the linear coefficient a'is within the range of a ± δ1. , The line segment Si and the line segment Sj are determined to be in the same straight line section, and the line segment Sj is determined to be in the same straight line section.
If there is a line segment Sj + 1 following, the above j + 1 is set as j and the above determination is repeated for a new line segment Sj,
The starting point of the line segment Si is the starting point of a continuous line segment in the same straight line section, and the end point of the last line segment Sj determined to be in the same straight line section is the end point of the continuous line segment in the same straight line section. A method for compressing processed shape data, the method including: Wherein the machining shape data configured by the machining shape data storage unit has been a plurality of successive stored in line processing type
A method for compressing processed shape data in a shape processing system in which a shape data compression unit performs compression processing, and the shape processing machine is operated using the compressed processing shape data to process the material to be processed into a target shape. Therefore, the compression processing by the processing shape data compressing means is performed by using the plurality of continuous lines from the processing shape data storage unit.
Retrieving a partial, by the similarity of linear coefficients of each line segment, if the continuous line and the step of determining whether or not collinear section, is the continuous line segment is determined to be in the same straight line segment Is a step of erasing the continuous line segment by connecting the start point and the end point of the continuous line segment with a straight line to form a new line segment.
And the data representing the new line segment as the machining shape data
And storing it in the machining shape data storage unit.
And determine whether the above-mentioned continuous line segments are in the same straight line section
The step of setting a constant θ1 that represents the similarity of the above-mentioned linear coefficients is preset .
And a line segment Si, Z = aX + b, Z = aY + b or Y =
It is expressed by a function of aX + b, and the line segment Sj (j:
i + 1 to n) is expressed by a function of Z = a'X + b ', Z = a'Y + b' or Y = a'X + b ', in the line segment Si and the line segment Sj shown by the above function, X
The crossing angle θi and the crossing angle θj with respect to any of the Y and Z axes are obtained, and in the relationship between the angle θi and the angle θj, if the above θj is within the range of θi ± θ1, the above line segment It is determined that Si and the line segment Sj are in the same straight line section, and the line segment Sj is determined to be in the same straight line section.
If there is a line segment Sj + 1 following, the above j + 1 is set as j and the above determination is repeated for a new line segment Sj,
The start point of the line segment Si is set as the start point of a continuous line segment in the same straight line section, and the end point of the last line segment Sj determined to be in the same straight line section is set as the end point of the continuous line segment in the same straight line section. A method for compressing processed shape data, the method including : 3. The machining shape data composed of a plurality of continuous line segments stored in the machining shape data storage unit is processed.
A method for compressing processed shape data in a shape processing system in which a shape data compression unit performs compression processing, and the shape processing machine is operated using the compressed processing shape data to process the material to be processed into a target shape. Therefore, the compression processing by the processing shape data compressing means is performed by using the plurality of continuous lines from the processing shape data storage unit.
Retrieving a partial, by the similarity of linear coefficients of each segment, determining whether successive segments is in the same straight line segment, the continuous line segment is determined to be in the same straight line segment In this case, the step of erasing the continuous line segment by connecting the start point and the end point of the continuous line segment with a straight line to form a new line segment
And the data representing the new line segment as the machining shape data
And storing it in the machining shape data storage unit.
And determine whether the above-mentioned continuous line segments are in the same straight line section
That step scan of preset constants γ1 representing the similarity of the straight line coefficient
And a line segment Si, Z = aX + b, Z = aY + b or Y =
It is expressed by a function of aX + b, and the line segment Sj (j:
i + 1 to n) is represented by a function of Z = a′X + b ′, Z = a′Y + b ′ or Y = a′X + b ′, and the linear coefficient a is represented by a trigonometric function value γ of sin θ or cos θ. , When the linear coefficient a ′ is expressed using the trigonometric function value γ ′ of sin θ ′ or cos θ ′,
In the relationship between the trigonometric function value γ and the trigonometric function value γ ′, if the trigonometric function value γ ′ is within the range of γ ± γ1, the line segment Si and the line segment Sj are on the same straight line. The line segment Sj that is determined to be in the section and is determined to be in the same straight line section
If there is a line segment Sj + 1 following, the above j + 1 is set as j and the above determination is repeated for a new line segment Sj,
The starting point of the line segment Si is the starting point of a continuous line segment in the same straight line section, and the end point of the last line segment Sj determined to be in the same straight line section is the end point of the continuous line segment in the same straight line section. A method for compressing processed shape data, the method including :